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At present, the only commercially available system for in vivo Corneal Confocal Microscopy enables unique insights into the corneal morphology, especially corneal nerves. Unfortunately—technology, user‐friendliness and image analysis of the standard platform has remained at the level of 15 years ago. This contribution presents cutting edge insights into new developments based on research within our German Research Foundation supported interdisciplinary research network. This covers a wide range of new developments addressing usability, large field as well as 3D imaging, dedicated contact cap designs, elastic image registration and AI based tissue classification. Furthermore, cutting edge technologies offer 4D imaging to perform dynamic investigations and multiwavelength as well as OCT‐guided Corneal Confocal Microscopy. Finally, key aspects demonstrating the potential of the technique for static and dynamic corneal nerves analysis will be presented. [ABSTRACT FROM AUTHOR]

Ocular biometry is a diagnostic method in ophthalmology that uses various techniques to measure the different parts of the eye. It involves the use of instruments that can measure the axial length of the eye, corneal curvature, anterior chamber depth, and other parameters related to the eye's structure. Ocular biometry is crucial in diagnosing and monitoring various eye conditions, especially cataracts but also glaucoma, and myopia. One of the most important techniques used in ocular biometry is optical biometry. Optical biometry involves the use of specialized devices that use light to measure the length of the eye. This technique is very accurate and is the gold standard in measuring axial length, which is essential in determining the correct power of intraocular lenses for cataract surgery as myopia and macular degeneration. Another technique used in ocular biometry is acoustical biometry. This technique uses sound waves to measure the axial length of the eye. Today, acoustical biometry is less commonly used than optical biometry but is still an important tool in certain cases. For example, in eyes with dense cataracts, where the optical media is opaque, acoustical biometry may be the only option for accurate measurement. This talk summarizes the up‐to‐date techniques in ocular biometry is an essential tool in ophthalmology for accurate diagnosis, monitoring, as well as treatment of various eye conditions, and addresses pit and pitfalls. [ABSTRACT FROM AUTHOR]

The cornea is a transparent outermost structure of the eye anterior segment comprising the highest density of innervated tissue. In the process of corneal innervation, trigeminal ganglion originated corneal nerves diligently traverse different corneal cell types in different corneal layers including the corneal stroma and epithelium. While crossing the stromal and epithelial cell layers during innervation, due to the existing physical contacts, close interactions occur between stromal keratocytes, epithelial cells, resident immune cells and corneal nerves. Furthermore, by producing various trophic and growth factors corneal cells assist in maintaining the growth and function of corneal nerves. Similarly, corneal nerve generated growth factors critically modify the corneal cell function in all the corneal layers. Due to their close association and contacts, on-going cross-communication between these cell types and corneal nerves play a vital role in the modulation of corneal nerve function, regeneration during wound healing. The present review highlights the influence of different corneal cell types and growth factors released from these cells on corneal nerve regeneration and function. [ABSTRACT FROM AUTHOR]

Introduction: Autologous serum eye drops (ASED) are used in the treatment of most severe stages of dry eye. Once introduced, it is currently considered impossible to return to other lubricating eye drops or other commercially available therapeutic regimen. Materials and Methods: In a randomized study, non-preserved high-molecular-weight hyaluronic acid eye drops were offered as an alternative to 11 patients using autologous serum treatment for at least 3 months. The control group (n = 5) continued their treatment with ASED. The verum group (n = 6) used very-high-molecular-weight hyaluronic eye drops (Comfort Shield®) instead of the ASED. Results: From four of initially six patients in the verum group that finished the study, 2 (50%) preferred to stay with the very-high-molecular-weight hyaluronic acid eye drops beyond the trial period, the other two returned to the earlier therapy with ASED. The control group continued their treatment as before and finished the study after 8 weeks. Conclusion: For the first time, artificial eye drops, i.e., high-molecular-weight hyaluronic acid eye drops, offered an acceptable alternative to ASED. Some patients perceived these drops as even better than the patient's own serum. This is the first evidence that optimization of the molecular structure of hyaluronic acid can be used to create eye drops that are perceived to be better than other tested tear substitutes and even patients' own serum. This offers a new treatment perspective for patients with very severe dry eye disease. [ABSTRACT FROM AUTHOR]

Objective: Magnetic resonance imaging (MRI) at 1.5 and 3.0 Tesla with small surface coils is a well-established procedure in the diagnosis of masses of the eye and orbital cavity. Until now histological examination has been required to obtain definitive information on tumor extent or possible infiltration of surrounding structures. With ultra-high-field MRI, however, it is possible to evaluate tumor morphology as well as possible extension into surrounding structures with submillimeter spatial resolution. Materials and Methods: We present a female patient with a uveal melanoma who underwent a preoperative MRI at 1.5 T (spatial resolution = 0.9 x 0.9 x 4 mm/voxel). Postoperatively, the enucleated specimen was examined in a 7.1 Tesla high-field MRI scanner (slice thickness = 500 µm, matrix size = 512 x 512 pixels, spatial resolution = 78 x 78 x 500 µm/voxel, acquisition time = 8:20 min per plane). Finally, the specimen was examined histologically, and the histological and MRI results were correlated. Results: Ultra-high-field MRI at 7.1 Tesla visualized the uveal melanoma and anatomical structures of the bulb with high resolution, enabling definitive assessment of tumor morphology and extent. Subsequent histological examination confirmed the MRI findings regarding origin, internal structure, and extent of the tumor. Conclusion: MR microscopy correlates strongly with histology, suggesting that this new imaging modality has the potential for noninvasively assessing tumor morphology, extent, and infiltration of surrounding structures. The examination was performed ex vivo and demonstrates that diagnostic assessment of malignant masses is feasible using high-resolution MR microscopy. [ABSTRACT FROM AUTHOR]

Introduction: The assessment of the corneal nerve fibre plexus with corneal confocal microscopy (CCM) is an upcoming but still experimental method in the diagnosis of early stage diabetic peripheral neuropathy (DPN). Using an innovative imaging technique—Heidelberg Retina Tomograph equipped with the Rostock Cornea Module (HRT-RCM) and EyeGuidance module (EG)—we were able to look at greater areas of subbasal nerve plexus (SNP) in order to increase the diagnostic accuracy. The aim of our study was to evaluate the usefulness of EG instead of single image analysis in diagnosis of early stage DPN. Methods: This prospective study was performed on 60 patients with type 2 diabetes mellitus, classified equally into two subgroups based on neuropathy deficient score (NDS): patients without DPN (group 1) or with mild DPN (group 2). The following parameters were analysed in the two subgroups: corneal nerve fibre length (CNFL; mm/mm2), corneal nerve fibre density (CNFD; no./mm2), corneal nerve branch density (CNBD; no./mm2). Furthermore, we compared the data calculated with the novel mosaic, EG-based method with those received from single image analysis using different quantification tools. Results: Using EG we did not find a significant difference between group 1 and group 2: CNFL (16.81 ± 5.87 mm/mm2 vs. 17.19 ± 7.19 mm/mm2, p = 0.895), CNFD (254.05 ± 115.36 no./mm2 vs. 265.91 ± 161.63 no./mm2, p = 0.732) and CNBD (102.68 ± 62.28 no./mm2 vs. 115.38 ± 96.91 no./mm2, p = 0.541). No significant difference between the EG method of analysing the SNP and the single image analysis of 10 images per patient was detected. Conclusion: On the basis of our results it was not possible to differentiate between early stages of large nerve fibre DPN in patients with type 2 diabetes mellitus via SNP analysis. To improve sensitivity and specificity of this method newer technologies are under current evaluation. Trial Registration: ClinicalTrials.gov Identifier NCT05326958. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the utility of high-resolution magnetic resonance imaging (MRI) in assessing the normal and refilled lens geometry in rabbits after lens-refilling surgery. Setting: University of Rostock, Rostock, Germany. Design: Experimental study. Methods: High-resolution ocular MRIs were acquired (7.1 T ClinScan) using a 2-channel coil with 4 coil elements and T2-weighted turbo spin-echo sequences (slice thickness 700 μm, field of view 40 mm × 40 mm) in rabbits after lens refilling surgery combined with intraoperative treatment to prevent lens epithelial cell proliferation. Single slices were used to assess the refilled lenses 3 years postoperatively. Results: The entire geometry (cross-sectional area, radius of curvature, axial and equatorial diameters) of the crystalline and refilled lenses was visualized by in vivo 7.1T MRI 3 years postoperatively (in-plane resolution: 125 μm × 125 μm). In refilled eyes, the capsule and the homogenous silicone polymer remained in close contact with no visible interface. The dimensions of the refilled lens were significantly smaller than those of the crystalline lens of the contralateral eye. Conclusions: High-resolution MRI allows in vivo visualization and analysis of the spatial arrangement of the lens in rabbit eyes after lens refilling surgery and overcomes a number of major limitations in the quantitative evaluation of the lens shape. Further efforts are required to optimize the amount of polymer injected during lens refilling to achieve a predictable refractive outcome after lens refilling surgery. Financial Disclosure: Drs. Stachs, Langner, Sternberg, Martin, Schmitz, Hosten and Guthoff have no financial or proprietary interest in any material or method mentioned. Additional financial disclosure is found in the footnotes. [ABSTRACT FROM AUTHOR]

Background: The gold standard for diagnosing Schistosoma mansoni infections is the detection of eggs from stool or biopsy specimens. The viability of collected eggs can be tested by the miracidium hatching procedure. Direct detection methods are often limited in patients with light or early infections, whereas serological tests and PCR methods fail to differentiate between an inactive and persistent infection and between schistosomal species. Recently, confocal laser scanning microscopy (CLSM) has been introduced as a diagnostic tool in several fields of medicine. In this study we evaluated CLSM for the detection of viable eggs of S. mansoni directly within the gut of infected mice. Methodology/Principal Findings: The confocal laser scanning microscope used in this study is based on the Heidelberg Retina Tomograph II scanning laser system in combination with the Rostock Cornea Module (image modality 1) or a rigid endoscope (image modality 2). Colon sections of five infected mice were examined with image modalities 1 and 2 for schistosomal eggs. Afterwards a biopsy specimen was taken from each colon section and examined by bright-field microscopy. Visualised eggs were counted and classified in terms of viability status. Conclusions/Significance: We were able to show that CLSM visualises eggs directly within the gut and permits discrimination of schistosomal species and determination of egg viability. Thus, CLSM may be a suitable non-invasive tool for the diagnosis of schistosomiasis in humans. [ABSTRACT FROM AUTHOR]

Purpose: Keratoconus is a predominantly bilateral form of corneal degeneration that is associated with central thinning and cone-shaped bulging of the cornea usually accompanied by a progressive reduction in visual acuity. A recent therapeutic option is cross-linking, a procedure designed to prevent the progression of keratoconus by the photochemical cross-linkage of collagen fibers. Patients and Methods: Eight eyes in 8 patients with progressive keratoconus were treated by the photochemical cross-linking method using riboflavin and UVA light. In addition to the usual ophthalmological examinations, patients were examined pre- and postoperatively by confocal in vivo laser scanning microscopy. Follow-up examinations were performed at 2 weeks and at 2, 4, 6 and 12 months postoperatively. Results: Complete regeneration of corneal epithelium was detected by 2 weeks after therapy at the latest. The sub-basal nerve plexus could not be visualized by confocal microscopy after treatment. Immediately after treatment, the anterior corneal stroma had a honeycombed appearance but without the typical hyperreflective keratocyte nuclei. At about 6 months postoperatively, the corneal stroma had virtually regained its normal configuration. After therapy, confocal microscopy revealed that corneal endothelium was normal in terms of cell density and morphology at every time point. Conclusions: Confocal in vivo laser scanning microscopy is an investigative technique that permits reproducible visualization of structural changes in the cornea (epithelium, stroma and endothelium) following collagen cross-linking with riboflavin and UVA light. Once epithelial healing is complete, the epithelium and endothelium appear to be unaffected by the treatment. The most noteworthy structural changes, which are detected on confocal microscopy shortly after treatment, involve the anterior and middle corneal stroma. Over the course of time, up to 12 months postoperatively, these changes show a definite tendency to regress. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Objective: The specific aim of this study is to measure the taste volume in healthy human subjects over a 2.5-month period and to demonstrate morphological changes of the peripheral taste organs. Material and methods: Eighteen human taste buds in four fungiform papillae (fPap) were examined over a 10-week period. The fungiform papillae investigated were selected based on the form of the papillae or the arrangement of surface taste pores. Measurements were performed over 10 consecutive weeks, with five scans in a day once a week. The following parameters were measured: height and diameter of the taste bud, diameter of the fungiform papilla and diameter of the taste pore. Results: The findings of this exploratory study indicated that (1) taste bud volumes changed over a 10-week period, (2) the interval between two volume maxima within the 10-week period was 3–5 weeks, and (3) the diameter of the fPap did not correlate with the volume of a single taste bud or with the volume of all taste buds in the fPap within the 10-week period. Conclusions: This exploratory in vivo study revealed changes in taste bud volumes in healthy humans with age-related gustatory sensitivity. These findings need to be considered when studying the effect of denervation of fungiform papillae in vivo using confocal microscopy. [Copyright &y& Elsevier]

J Oral Pathol Med (2010) 39: 318–327 Background: A rigid confocal endoscope has been developed to assess the oral squamous epithelium of mice and to determine sensitivity, specificity, and accuracy of this new technology. Methods: This endoscope is connected to the commercially available Heidelberg Retina Tomograph (HRT). HRT is a device with a 670-nm diode laser designed to acquire topographical measurements of the optic nerve head. Real-time rigid confocal endoscopy is demonstrated by imaging the epithelial lesions of a mice model. Six-week-old male C57Bl/6 mice were randomly divided into a non-treated group ( n = 10) and into a 4-nitroquinoline 1-oxide (4-NQO)-treated group ( n = 50). In the 4-NQO-treated group, the mice obtained 4-nitroquinoline 1-oxide in the drinking water (100 μg/ml) to induce tumourigenesis in the mouse tongue. The 4-NQO-solution was diluted in the drinking water for mice. After an 8–16-week carcinogen treatment with 4-NQO ( ad libitum), mouse tongues were dissected within 3 h after CO2 overdose. After confocal microscopy of all lesions of the tongue, conventional histopathological investigation was performed. Results: The inter-rater reliability for the two observers of the confocal microscopic findings was found to be Kappa = 0.59 ( P < 0.001). The penetration depth varied in the healthy tissue of the underside of the tongue throughout this study and was measured between 104 and 240 μm. In keratotic lesions, the penetration depths were diminished and varied between 80 and 140 μm. Strong keratinization inhibits the evaluation of the epithelium. For differentiation between low-grade and high-grade squamous intra-epithelial lesions, a sensitivity and specificity of 73% and 88% was reached. Conclusions: The animal experiment with this non-invasive new technology indicates that this imaging technology facilitates the detection of pre-cancerous lesions of the underside of the oropharynx. Human studies on oropharyngeal and laryngeal lesions are needed to prove the applicability of this method in the field of otorhinolaryngology. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate a new method for visualizing femtosecond laser pulse–induced microincisions inside crystalline lens tissue. Setting: Laser Zentrum Hannover e.V., Hannover, Germany. Method: Lenses removed from porcine eyes were modified ex vivo by femtosecond laser pulses (wavelength 1040 nm, pulse duration 306 femtoseconds, pulse energy 1.0 to 2.5 μJ, repetition rate 100 kHz) to create defined planes at which lens fibers separate. The femtosecond laser pulses were delivered by a 3-dimension (3-D) scanning unit and transmitted by focusing optics (numerical aperture 0.18) into the lens tissue. Lens fiber orientation and femtosecond laser–induced microincisions were examined using a confocal laser scanning microscope (CLSM) based on a Rostock Cornea Module attached to a Heidelberg Retina Tomograph II. Optical sections were analyzed in 3-D using Amira software (version 4.1.1). Results: Normal lens fibers showed a parallel pattern with diameters between 3 μm and 9 μm, depending on scanning location. Microincision visualization showed different cutting effects depending on pulse energy of the femtosecond laser. The effects ranged from altered tissue-scattering properties with all fibers intact to definite fiber separation by a wide gap. Pulse energies that were too high or overlapped too tightly produced an incomplete cutting plane due to extensive microbubble generation. Conclusions: The 3-D CLSM method permitted visualization and analysis of femtosecond laser pulse–induced microincisions inside crystalline lens tissue. Thus, 3-D CLSM may help optimize femtosecond laser–based procedures in the treatment of presbyopia. [Copyright &y& Elsevier]

Patients with cystic fibrosis (CF) are at risk to develop CF related diabetes (CFRD) and subsequently even diabetic neuro- and/or vasculopathy. We sought to determine if there are typical signs of diabetes-related retinal alterations present in CF patients with preserved and impaired glycemic control. During routine annual examination CF patients were offered an additional 7-day period of real time continuous glucose monitoring (rtCGM) and an ophthalmological examination including retinal optical coherence tomography (OCT). Patients were categorized according to the glycemic control, i.e. the results of an oral glucose tolerance test (OGTT) and rtCGM were taken into consideration. OCT data was analyzed by our previously published visual analysis software generating dedicated and spatially resolved deviation maps for visualization and quantification of differences in total retinal thickness and thickness of retinal nerve fiber layer (RNFL) as well as ganglion cell layer (GCL) in comparison to age-matched healthy controls and patients with either type 1 or type 2 diabetes mellitus. Results of the rtCGM and/or OGTT enabled discrimination between patients with normal glycemic control (CFNG; n = 6), with abnormal glycemic control (CFAG; n = 6) and overt CFRD (n = 4). OCT data indicates gradually increasing retinal thinning in all 3 groups, depending on the degree of glucose metabolism disorder compared to healthy controls. At the foveal region total retinal thickness and GCL thickness were significantly thinner in CFRD patients compared to CFNG patients (total retinal thickness: 260.4 µm (239.3–270.8) vs. 275.4 µm (254.3–289.5); GCL: 11.82 µm (11.16–15.25) vs. 17.30 µm (13.95–19.82); each p < 0.05). Although we investigated a rather small number of patients, we obtained evidence that intraretinal neurodegenerative changes occur in each of our subgroups (CFNG, CFAG, CFRD). Beyond this, our results favor the detrimental role of additional diabetes, as the deviations from healthy controls were most pronounced in the CFRD group and are similar to those seen in patients suffering from type 1 or type 2 diabetes. [ABSTRACT FROM AUTHOR]

In vivo large-area confocal laser scanning microscopy (CLSM) of the human eye using EyeGuidance technology allows a large-scale morphometric assessment of the corneal subbasal nerve plexus (SNP). Here, the SNP of a patient suffering from diabetes and associated late complications was analyzed. The SNP contained multiple clusters of large hyperintense, stellate-shaped, cellular-like structures. Comparable structures were not observed in control corneas from healthy volunteers. Two hypotheses regarding the origin of these atypical structures are proposed. First, these structures might be keratocyte-derived myofibroblasts that entered the epithelium from the underlying stroma through breaks in Bowman's layer. Second, these structures could be proliferating Schwann cells that entered the epithelium in association with subbasal nerves. The nature and pathophysiological significance of these atypical cellular structures, and whether they are a direct consequence of the patient's diabetic neuropathy/or a non-specific secondary effect of associated inflammatory processes, are unknown. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of high molecular weight hyaluronan (HMWHA) eye drops on subbasal corneal nerves in patients suffering from severe dry eye disease (DED) and to evaluate the damage of subbasal corneal nerves associated with severe DED. Designed as an international, multicenter study, 16 patients with symptoms of at least an Ocular Surface Disease Index (OSDI) score of 33, and corneal fluorescein staining (CFS) of at least Oxford grade 3, were included and randomized into two study arms. The control group continued to use their individual optimum artificial tears over the study period of eight weeks; in the verum group, the artificial tears were substituted by eye drops containing 0.15% HMWHA. At the baseline visit, and after eight weeks, the subbasal nerve plexus of 16 patients were assessed by confocal laser scanning microscopy (CSLM). The images were submitted to a masked reading center for evaluation. Results showed a significant increase of total nerve fiber lengths (CNFL) in the HMWHA group (p = 0.030) when compared to the control group, where the total subbasal CNFL did not significantly change from baseline to week 8. We concluded that in severe DED patients, HMWHA from topically applied eye drops could cross the epithelial barrier and reach the subbasal nerve plexus, where it exercised a trophic effect. [ABSTRACT FROM AUTHOR]

Background: The gold standard for the diagnosis of schistosomiasis is the detection of the parasite's characteristic eggs in urine, stool, or rectal and bladder biopsy specimens. Direct detection of eggs is difficult and not always possible in patients with low egg-shedding rates. Confocal laser scanning microscopy (CLSM) permits non-invasive cell imaging in vivo and is an established way of obtaining high-resolution images and 3-dimensional reconstructions. Recently, CLSM was shown to be a suitable method to visualize Schistosoma mansoni eggs within the mucosa of dissected mouse gut. In this case, we evaluated the suitability of CLSM to detect eggs of Schistosoma haematobium in a patient with urinary schistosomiasis and low egg-shedding rates. Methodology/Principal Findings:The confocal laser scanning microscope used in this study was based on a scanning laser system for imaging the retina of a living eye, the Heidelberg Retina Tomograph II, in combination with a lens system (image modality). Standard light cystoscopy was performed using a rigid cystoscope under general anaesthesia. The CLSM endoscope was then passed through the working channel of the rigid cystoscope. The mucosal tissue of the bladder was scanned using CLSM. Schistoma haematobium eggs appeared as bright structures, with the characteristic egg shape and typical terminal spine. Conclusion/Significance: We were able to detect schistosomal eggs in the urothelium of a patient with urinary schistosomiasis. Thus, CLSM may be a suitable tool for the diagnosis of schistosomiasis in humans, especially in cases where standard diagnostic tools are not suitable. [ABSTRACT FROM AUTHOR]

Aims/Purpose: This cohort study investigates how the static and dynamic vessel parameters differ in patients with vascular occlusions and if there are any variations between the different types of vessel occlusion. Methods: Patients with the diagnosis of branch retinal artery obstruction BRAO, central retinal artery obstruction CRAO, branch retinal vein obstruction BRVO, central retinal vein obstruction CRVO, anterior ischaemic optic neuropathy AION and any combination of these Combo were included in our study. During their inpatient stay for cardiovascular diagnostics all patients were examined via static and dynamic vessel analysis (IMEDOS Health GmbH, Jena) to obtain the arteriovenous ratio (AVR), the central retinal artery equivalent (CRAE), the central retinal vein equivalent (CRVE) and the flicker light induced dilation of the retinal arteries (FLA) and veins (FLV). The vessel density was determined via OCT angiography (Heidelberg Engineering GmbH, Heidelberg). Results: 34 patients (70% male; 30% female; mean age 69.6 ± 11.3 years) with 9 (26.5%) CRVO, 8 (23.5%) AION, 5 (14.7%) BRAO and 4 (11.8%) CRAO, BRVO and Combo each have been included. The best visual acuity (BCVA) of the diseased eye differed significantly between the groups (AION 0.41 ± 0.61, CRAO 2.40 ± 0.20, BRAO 0.16 ± 0.05, CRVO 0.81 ± 0.86, BRVO 0.18 ± 0.10, Combo 1.53 ± 0.68; p < 0.001) whereas the BCVA of the healthy eyes were comparable. The CRVE showed a significant difference between the groups CRAO – CRVO (p = 0.008), CRAO – Combo (p < 0.001) and BRAO–Combo (p = 0.026). The FLV of the diseased eye was significantly higher in patients with AION than in the CRAO group (p = 0.049). The parameters of the static vessel analysis of the healthy eyes were comparable. Conclusions: Preliminary analysis shows significant differences of individual parameters of the retinal vessel analysis between different types of vascular occlusion. The diagnostic and research benefit for the individual patient remains to be further evaluated. [ABSTRACT FROM AUTHOR]

Currently, the effect of prenatal ultrasound on foetal development is intensively discussed and the guidelines for prenatal diagnostics have been changed. However, data supporting these concerns are scarce. Therefore, we used an established in ovo model of the chicken embryo to investigate cell proliferation and apoptosis within the retina. A total of 21 chicken eggs were fenestrated on Day 5 and allocated to either the control (n = 8) or exposition group (n = 13). The exposition group was treated with pulsed‐wave Doppler ultrasound (PWD) for 10 min while controls remained without treatment. After subsequent incubation (6–48 h), the eggs were sacrificed, and chicken embryos were examined morphologically (HE‐staining) and immunohistochemically. Counting of apoptotic and proliferating cells per retina was performed using antibodies specific for phospho‐histone‐H3 and active caspase‐3 in combination with a biotin‐labelled secondary antibody and peroxidase conjugated avidin–biotin complex for chromogenic detection. Due to a rather low number of specimens at each time point after ultrasound exposition, we neglected the effects of incubation time and focused on treatment effects. This approach revealed that the median number of proliferating cells is reduced after 10 min of exposure to PWD (569 vs. 766), while the number of apoptotic cells is fairly comparable between groups (5 vs. 6). Our data contribute to a better understanding of prenatal US on foetal development by suggesting that PWD could have an impact on the number of proliferating cells in the developing chicken retina and therefore justify further investigations. [ABSTRACT FROM AUTHOR]

The article comments on the imaging applications of in vivo confocal (IVC) microscopy in inherited corneal disease. It references a report by D.V. Patel and C.N.J. McGhee in the January 2007 issue of "Clinical and Experimental Ophthalmology," which highlights the increasing importance of IVC imaging in the human cornea. The authors believe that IVC microscopy can identify the opacities in the cornea as well in the tarsal conjunctiva.

MR microscopy (MRM) is known as ultra‐high‐field (UHF) magnetic resonance imaging with an in‐plane spatial resolution of <100 μm, yields highly resolved non‐invasive anatomical imaging and allows longitudinal assessment of embryonic avian development. The aim of the present study was to evaluate the feasibility of in vivo anatomical MRI assessment of the developing upper extremity of the chicken. Thirty‐eight fertilized chicken eggs were examined at 7 Tesla acquiring high‐resolution T2‐weighted images with an in‐plane resolution of 74 × 74 μm. To reduce motion artefacts, the eggs were moderately cooled before and during MRI. Development of the upper extremity was anatomically and quantitatively assessed. Chondrification and ossification on MRI were correlated with histological examination. MRM allowed the identification of the embryo from stage D5 onwards. First chondrification of the upper extremity was visible at stage D7, and the differentiation of the forearm was possible from stage D9 throughout the developmental period with excellent correlation to histology. MRM also allowed the differentiation between cortical and medullary bone as well as the detection of chondrified areas. UHF MRM allows the in vivo and in ovo evaluation of the upper limb during embryonic development and provides non‐invasive longitudinal anatomical information. This technique allows longitudinal studies of the same embryo during the developmental period and may therefore provide further insights into the development of the upper extremity. With improved coil technique and increasing availability of UHF MR systems, there is great potential regarding several research topics in experimental musculoskeletal radiology. [ABSTRACT FROM AUTHOR]

Simple Summary: The study's purpose was to determine whether neurotoxic signs in breast cancer patients receiving taxane (paclitaxel) chemotherapy correlate with retinal or corneal nerve changes in a longitudinal study combining oncological examinations with advanced biophotonic imaging techniques. Recruited breast cancer patients underwent regular monitoring sessions including the clinical assessment of their quality of life and neurological scores, ophthalmological status, retinal optical coherence tomography, and large area confocal laser scanning microscopy of their corneal subbasal nerve plexus (SNP). The study revealed two key breakthroughs: an observable increase in retinal thickness and the examination of identical corneal SNP large-area mosaics over time. Consequently, advanced biophotonic imaging techniques could represent a powerful diagnostic tool for the objective assessment of the severity of adverse events, wherein oncologists and ophthalmologists could benefit from each other, leading to a better outcome for the patient. A common severe neurotoxic side effect of breast cancer (BC) therapy is chemotherapy-induced peripheral neuropathy (CIPN) and intervention is highly needed for the detection, prevention, and treatment of CIPN at an early stage. As the eye is susceptible to neurotoxic stimuli, the present study aims to determine whether CIPN signs in paclitaxel-treated BC patients correlate with ocular changes by applying advanced non-invasive biophotonic in vivo imaging. Patients (n = 14, 10 controls) underwent monitoring sessions after diagnosis, during, and after therapy (T0-T3). Monitoring sessions included general anamnesis, assessment of their quality of life, neurological scores, ophthalmological status, macular optical coherence tomography (OCT), and imaging of their subbasal nerve plexus (SNP) by large-area confocal laser-scanning microscopy (CLSM). At T0, no significant differences were detected between patients and controls. During treatment, patients' scores significantly changed while the greatest differences were found between T0 and T3. None of the patients developed severe CIPN but retinal thickenings could be detected. CLSM revealed large SNP mosaics with identical areas while corneal nerves remained stable. The study represents the first longitudinal study combining oncological examinations with advanced biophotonic imaging techniques, demonstrating a powerful tool for the objective assessment of the severity of neurotoxic events with ocular structures acting as potential biomarkers. [ABSTRACT FROM AUTHOR]

One major complication after fistulating glaucoma surgeries are fibroblast-mediated scarring processes and their specific prevention is key in the development of novel pharmaceutical concepts. Within this study a possible antifibrotic potential of kitasamycin (KM) in a transforming growth factor (TGF)-β1-mediated fibroblast model was evaluated in vitro. Primary ocular fibroblasts were isolated, cultivated and a dose–response test including determination of the half maximal effective concentration (EC50) for KM was conducted. Transformation of fibroblasts into myofibroblasts was induced by TGF-β1and immunofluorescence (IF), and Western blot (WB) analyses were performed with fibroblasts and myofibroblasts. IF analyses were carried out using antibodies against α-smooth muscle actin (α-SMA) and fibronectin, and protein detection of intracellular and extracellular proteins was performed by WB. Using the dose–response test, the viability, cytotoxicity and EC50 of KM after 24 and 48 h were determined. Fibroblasts exposed to various KM concentrations showed no increase in α-SMA and extracellular matrix expression. In TGF-ß1-stimulated myofibroblasts, KM inhibited the expression of α-SMA and fibronectin in a concentration-dependent manner. These findings demonstrate that KM could impair the transformation of fibroblasts into myofibroblasts and the expression of proteins involved in fibrotic processes, representing a potential agent for specific fibrosis prevention in future therapeutic concepts. [ABSTRACT FROM AUTHOR]

In glaucoma surgery, fibrotic processes occur, leading to impairment of liquid outflow. Activated fibroblasts are responsible for postoperative scarring. The transforming growth factor-β (TGF-β) pathway plays a key role in fibroblast function, differentiation and proliferation. The aim of this study was the characterization of the fibrotic potential of two subtypes of primary human ocular fibroblasts and the attempt to inhibit fibrotic processes specifically, without impairing cell viability. For fibrosis inhibition we focused on the small molecule pirfenidone, which has been shown to prevent pulmonary fibrosis by the decrease of the expression of TGF-β1, TGF-β2 and TGF-β3 cytokines. For in vitro examinations, isolated human primary fibroblasts from Tenon capsule and human intraconal orbital fat tissues were used. These fibroblast subpopulations were analyzed in terms of the expression of matrix components responsible for postoperative scarring. We concentrated on the expression of collagen I, III, VI and fibronectin. Additionally, we analyzed the expression of α-smooth muscle actin, which serves as a marker for fibrosis and indicates transformation of fibroblasts into myofibroblasts. Gene expression was analyzed by rtPCR and synthesized proteins were examined by immunofluorescence and Western blot methods. Proliferation of fibroblasts under different culture conditions was assessed using BrdU assay. TGF-β1 induced a significant increase of cell proliferation in both cell types. Also the expression of some fibrotic markers was elevated. In contrast, pirfenidone decreased cell proliferation and matrix synthesis in both fibroblast subpopulations. Pirfenidone slightly attenuated TGF-β1 induced expression of fibronectin and α-smooth muscle actin in fibroblast cultures, without impairing cell viability. To summarize, manipulation of the TGF-β signaling pathway by pirfenidone represents a specific antifibrotic approach with no toxic side effects in two human orbital fibroblast subtypes. We presume that pirfenidone is a promising candidate for the treatment of fibrosis following glaucoma surgery. [ABSTRACT FROM AUTHOR]

Presents an erratum for the article 'An image plate chamber for x-ray diffraction experiments in Debye-Scherrer geometry,' which was published in the 2000 issue of the periodical 'Review of Scientific Instruments.'

A new design for implementation of x-ray diffraction experiments is proposed. The exploitation of the imaging plate technique opens new possibilities to carry out diffraction experiments. The detector chamber in Debye-Scherrer geometry equipped with an image plate takes advantage of this technology such as high resolution, high sensitivity, linearity in intensity, and linearity over the detector area. The proof of this measurement principle is demonstrated by presentation of the x-ray diffraction pattern of corundum (crystalline), nickel (crystalline), and sodium borate (amorphous). © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Background: Current knowledge of the human fetal and embryonic development relies on early descriptive studies of humans and from experimental studies of laboratory animals and embryos. Taking the upper extremity as an example, this study explores the potential of magnetic resonance microscopy (MRM) for the assessment of the development of the fetal upper extremity and discusses its correlation with histological findings. Methods: Ex vivo MRM at 7.1 T (Clin Scan, Bruker Biospin, Germany) was performed in 10 human specimens at 8 to 12 weeks of gestational age (GA). In-plane resolution was 20 μm with a slice thickness of 70 μm. MRM was followed by histological work-up of the specimens. MRM images were then correlated with conventional histology with a focus on the presence of chondrification and ossification. Results: Ossification of the upper human extremity is detectable at 8 weeks GA in the humerus and the long bones of the forearm. There is excellent correlation for location and size of ossification between MRM and conventional histology. MRM imaging is in accordance with historical studies. Conclusion: Ex vivo MRM for the non-invasive assessment of the embryonic and fetal development of the upper human extremity is feasible. It may provide an accurate complementary tool for the evaluation of embryological development. [ABSTRACT FROM AUTHOR]

Paclitaxel and trastuzumab have been associated with adverse effects including chemotherapy-induced peripheral neuropathy (CIPN) or ocular complications. In vivo confocal laser scanning microscopy (CLSM) of the cornea could be suitable for assessing side effects since the cornea is susceptible to, i.e., neurotoxic stimuli. The study represents a one-year follow-up of a breast cancer patient including large-area in vivo CLSM of the subbasal nerve plexus (SNP), nerve function testing, and questionnaires during paclitaxel and trastuzumab therapy. Six monitoring sessions (one baseline, four during, and one after therapy) over 58 weeks were carried out. Large-area mosaics of the SNP were generated, and identical regions within all sessions were assigned. While corneal nerve morphology did not cause alterations, the number of dendritic cells (DCs) showed dynamic changes with a local burst at 11 weeks after baseline. Simultaneously, paclitaxel treatment was terminated due to side effects, which, together with DCs, returned to normal levels as the therapy progressed. Longitudinal in vivo CLSM of the SNP could complement routine examinations and be helpful to generate a comprehensive clinical picture. The applied techniques, with corneal structures acting as biomarkers could represent a diagnostic tool for the objective assessment of the severity of adverse events and the outcome. [ABSTRACT FROM AUTHOR]

The morphometric assessment of the corneal subbasal nerve plexus (SNP) by confocal microscopy holds great potential as a sensitive biomarker for various ocular and systemic conditions and diseases. Automated wide-field montages (or large-area mosaic images) of the SNP provide an opportunity to overcome the limited field of view of the available imaging systems without the need for manual, subjective image selection for morphometric characterization. However, current wide-field montaging solutions usually calculate the mosaic image after the examination session, without a reliable means for the clinician to predict or estimate the resulting mosaic image quality during the examination. This contribution describes a novel approach for a real-time creation and visualization of a mosaic image of the SNP that facilitates an informed evaluation of the quality of the acquired image data immediately at the time of recording. In cases of insufficient data quality, the examination can be aborted and repeated immediately, while the patient is still at the microscope. Online mosaicking also offers the chance to identify an overlap of the imaged tissue region with previous SNP mosaic images, which can be particularly advantageous for follow-up examinations. [ABSTRACT FROM AUTHOR]

. Purpose: The aim of our study was to investigate the biomechanical properties of the cornea in primary congenital glaucoma (PCG) and to identify the potential ocular determinants, which affect the corneal biomechanical metrics. Methods: Corneal hysteresis (CH), corneal resistance factor (CRF) and central corneal thickness (CCT) were measured in 26 patients with PCG (40 eyes) with the aid of ocular response analyser. In vivo laser-scanning confocal microscopy was used for the estimation of stromal keratocyte density (KD) and the evaluation of corneal endothelium. Twenty normal subjects (40 eyes) served as controls. Student's t-test and Pearson's correlation coefficients were used for statistical analysis. p Values <0.05 were considered statistically significant. Results: Corneal hysteresis, CRF and CCT were significantly reduced in patients with PCG (all p < 0.05). Corneal hysteresis and CRF negatively correlated with the corneal diameter in both groups ( r1 = −0.53, r2 = −0.66, p < 0.001 for CH and r1 = −0.61, r2 = −0.69, p < 0.001 for CRF). Moreover, we identified a significant correlation between CH and CRF with CCT in both groups ( r1 = 0.51, r2 = 0.48, p < 0.001 for CH and r1 = 0.45, r2 = 0.44, p < 0.001 for CRF). Mean KD was significantly reduced both in the anterior and posterior corneal stroma in patients with PCG (764 ± 162 and 362 ± 112 cells/mm2, respectively) compared with controls (979 ± 208 and 581 ± 131 cells/mm2, respectively) (p < 0.001). There was no significant correlation between the keratocyte density in anterior and/or posterior stroma and CH or CRF in any group ( r1 = 0.29, r2 = 0.31, p < 0.06). Mean endothelial cell density was also significantly reduced in PCG group (2920 ± 443 cells/mm2) compared with control group (3421 ± 360 cells/mm2) (p < 0.001). Pleomorphism and polymegalism were significantly increased in corneal endothelium of patients with PCG. Conclusions: Our results showed a significant reduction in CH and CRF in PCG. Both CH and CRF were negatively correlated with corneal diameter. A significant correlation of CH and CRF with CCT was identified in both groups. Keratocyte density was decreased in PCG, but did not have a significant impact on CH and CRF. Mean endothelial density was also decreased in PCG. Our results suggest that reduced CCT and increased corneal diameter are major ocular determinants for the modified corneal biomechanical profile in PCG, while cellular alterations in corneal stroma and endothelium have no significant biomechanical impact. [ABSTRACT FROM AUTHOR]

Collagen cross-linking (CXL) using UVA light and riboflavin (vitamin B2) was introduced as a clinical application to stabilize the cornea by inducing cross-links within and between collagen fibers. CXL has been investigated extensively and has been shown clinically to arrest the progression of keratoconic or post-LASIK ectasia. With its minimal cost, simplicity, and proven positive clinical outcome, CXL can be regarded as a useful approach to reduce the number of penetrating keratoplasties performed. Small case series have also indicated that CXL is beneficial in corneal edema by reducing stromal swelling behavior and in keratitis by inhibiting pathogen growth. Despite these encouraging results, CXL remains a relatively new method that is potentially associated with complications. Aspects such as side effects and recurrence rates have still to be elucidated. In light of the growing interest in CXL, our paper summarizes present knowledge about this promising approach. We have intentionally endeavored to include the more relevant studies from the recent literature to provide an overview of the current status of CXL. [ABSTRACT FROM AUTHOR]

Background/Aims: A clinical approach to prevent secondary cataract after lens implantation involves the intraocular application of pharmacological agents. The goals of our study were to develop an ex vivo model to test the drug effectiveness for lens epithelial cell ablation from the basal membrane and to verify the data in rabbit intraocular lens implantation experiments. Methods: Human capsular rhexis specimens were incubated with drugs and the residual cells were differentiated by use of the Live-Dead assay and quantified by staining with Hoechst dye. After phakoemulsification of rabbit eyes and before intraocular lens implantation, capsular bags were filled with drug-loaded hyaluronic acid for 5 min. Results: An ex vivo model was established which allows the testing of drugs on lens epithelial cell ablation. Drug treatment reduced the number of viable cells on the specimens drastically, ranging between 0.44 ± 0.53% (6.0 ± 7.3 cells/mm2) for disulfiram, 0.27 ± 0.50% (3.7 ± 6.9 cells/mm2) for methotrexate and 0.07 ± 0.19% (0.1 ± 0.27 cells/mm2) for actinomycin D. Rabbit eyes treated with a mixture of methotrexate/actinomycin D showed no posterior capsule opacification at 4 months and a low opacification 6 months postoperatively. Without drug treatment low opacification starts 6 weeks postoperatively. Conclusions: The drug screening in the described ex vivo model can help to reduce the number of preclinical studies for secondary cataract prevention. The successful ex vivo cell ablation by methotrexate/actinomycin D was confirmed by a delayed in vivo secondary cataract formation. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The demands of modern ophthalmology have evolved from descriptive findings from the slit lamp to in vivo assessment of cellular level changes. Nowadays, the latter can be provided by in vivo confocal microscopy. This article gives an overview of confocal principles using tandem scanning, scanning slit and laser scanning techniques used in ophthalmology. The main part of the paper describes the clinical applications emphasizing the anatomy of the normal and pathological cornea, and illustrates side-effects of topical medication, contact lens wear, cross-linking and refractive surgery. Finally, a summary about experimental applications, including animal studies, surface characterization and volume rendering as well as future developments, is given. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging of the eye and orbit (MReye) is a cross-domain research field, combining (bio)physics, (bio)engineering, physiology, data sciences and ophthalmology. A growing number of reports document technical innovations of MReye and promote their application in preclinical research and clinical science. Realizing the progress and promises, this review outlines current trends in MReye. Examples of MReye strategies and their clinical relevance are demonstrated. Frontier applications in ocular oncology, refractive surgery, ocular muscle disorders and orbital inflammation are presented and their implications for explorations into ophthalmic diseases are provided. Substantial progress in anatomically detailed, high-spatial resolution MReye of the eye, orbit and optic nerve is demonstrated. Recent developments in MReye of ocular tumors are explored, and its value for personalized eye models derived from machine learning in the treatment planning of uveal melanoma and evaluation of retinoblastoma is highlighted. The potential of MReye for monitoring drug distribution and for improving treatment management and the assessment of individual responses is discussed. To open a window into the eye and into (patho)physiological processes that in the past have been largely inaccessible, advances in MReye at ultrahigh magnetic field strengths are discussed. A concluding section ventures a glance beyond the horizon and explores future directions of MReye across multiple scales, including in vivo electrolyte mapping of sodium and other nuclei. This review underscores the need for the (bio)medical imaging and ophthalmic communities to expand efforts to find solutions to the remaining unsolved problems and technical obstacles of MReye, with the objective to transfer methodological advancements driven by MR physics into genuine clinical value. [ABSTRACT FROM AUTHOR]

Methods for visual or quantitative exploration of the cellular morphology of the cornea based on inherent three‐dimensional features open up completely new diagnostic possibilities. However, previous approaches to confocal microscopy of the cornea using mechanical 3D scanning strategies are slow and thus only partially suitable for in vivo investigations. Addressing these shortcomings, the idea of developing a novel confocal microscopic technique for three‐dimensional in vivo imaging of the cellular morphology of the cornea is aimed. By exploiting induced chromatic aberration using a swept‐source laser in conjunction with a specifically designed high‐dispersion optic, an extremely fast method for focal positioning in the tissue shall be developed. Utilizing a dedicated laser line scanning, will enable the display of sectional images in real time. These are comparable to slit lamp images, but with cellular resolution. Furthermore, with an x–y scanning protocol, corneal volumes can be acquired in less than 1 s. The project thus paves the way for cellular 3D slit‐lamp microscopy and, in perspective, provides ophthalmologists with further methods for dedicated diagnostics of ocular surface diseases. This paper summarizes the concept of this novel approach. [ABSTRACT FROM AUTHOR]

Purpose: To reduce capsular opacification by a peri‐surgical treatment of the lens capsule with drugs in an in vivo rabbit model. Lens‐refilling surgery is a potential therapeutic intervention to treat patients with a cataract lens. The lens material is replaced with an injectable (bio)polymer that retains the natural mechanical and optical lens properties, therewith allowing accommodation. The occurrence of capsular opacification mediated by lens epithelial cells negatively affects accommodation and vision and should be avoided in this lens restoration approach. Methods: An in vivo rabbit animal model was used with lens replacement with a silicone‐based gel‐like polymer and concurrent treatment of the lens epithelium with drugs. A case‐study approach was applied as both drug combinations and implantation times were varied. The following drugs were investigated for their potential to prevent capsular opacification long‐term: actinomycin D, methotrexate, paclitaxel and Tween‐20. All were administered in a hyaluronic acid vehicle. The rabbits were clinically followed for periods up to 4 years postimplantation. Eyes, corneas and lenses were analysed post‐mortem using MRI and confocal microscopy. Results: Treatment combinations containing actinomycin D generally led to the least appearance of capsular fibrosis. The use of Tween‐20 or paclitaxel without actinomycin D resulted in much earlier and pronounced fibrotic responses. The aspect of capsular opacification was highly variable in individual animals. Application of the drugs in a hyaluronic acid vehicle appeared to be a safe method that spared the corneal endothelium. Conclusion: The feasibility of long‐term prevention of fibrosis over a period of more than 4 years has been demonstrated in lens refilling in the rabbit model. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the use of deviation maps (DevMs) to understand thickness changes of inner retinal layers in optical coherence tomography (OCT) data. To test a new visual analytics (VA) method with reduced complexity of OCT data analysis by comparing the layer thickness of children with type 1 diabetes mellitus (T1DM) to matched controls. Methods: OCT was performed on unilateral eyes of 26 children with T1DM without diabetic retinopathy and 29 healthy children to obtain macular volume scans. Subsequently, segmented inner retinal layers were analyzed using VA. Deviation maps were generated to readily visualize thickness differences between both groups and to investigate thickness changes of individual patients in relation to the control group. Results: In DevMs of the patient group, the total retina (TR) demonstrated localized, irregular areas of thinning (mean ± standard deviation) involving foveal center, inner macula, and inferior-nasal outer macula (−9.31 ± 1.73 µm; p < 0.05). Similarly, retinal nerve fiber layer showed continuous and localized areas of thinning in both inner and outer macula, extending nasally (−5.45 ± 4.31 µm; p < 0.05). In DevMs of individual patients, the TR and inner retinal layers revealed remarkable changes in thickness that were present between patients at both late and early stages of diabetes. Conclusion: The VA method simplifies the in-depth analysis of OCT volume data from different groups and is effective in detecting retinal thickness changes in children with diabetes. It can be easily adopted in a clinical set-up and intuitively used in complex multidisciplinary studies. [ABSTRACT FROM AUTHOR]

Objective: Children with chronic kidney diseases (CKD) are at risk for neurological diseases at early adulthood. Spectral-domain optical coherence tomography (SD-OCT) of the retina is especially suitable for determination of intraretinal layer thickness. We wonder whether retinal thinning is already present in pediatric patients with mild-to-moderate CKD. Patients and Methods: Children (n = 15; 14.9 ± 2.4 years) with mild-to-moderate CKD (median eGFR of 95ml/min/1.73m2; range: 28-187ml/min/1.73m2) due to glomerulopathy, congenital anomalies of kidney and urinary tract (CAKUT), or haemolytic uremic syndrome (HUS) underwent a detailed ophthalmologic examination including high-resolution SD-OCT. Three OCT scans were obtained from the right eyes of all patients. Within each scan, retinal layers were separated and the mean thickness was determined at the foveal, parafoveal, and perifoveal area. The results were compared to those we obtained previously from healthy children. Results: At the parafoveal area, thickness (median, range) of the total retina (ALL), ganglion cell layer (GCL), and inner plexiform layer (IPL) were reduced compared to healthy volunteers (339µm, (288-361µm) vs. 348µm, (320-385µm); 49.8µm (30.5-56.6µm) vs. 53.5μm (49.5-60.5µm) and 41.0µm (29.4-43.7µm) vs. 43.46µm (39.5-46.3μm); each p < 0.05). The intraretinal thickness measurements at the foveal and perifoveal areas revealed no statistically significant differences between patients and controls. Conclusion: Distinct changes within the parafoveal area of the total retina, GCL, and IPL are present in children with mild-to-moderate CKD. Prospective studies are required to assess the clinical significance of our findings. [ABSTRACT FROM AUTHOR]

Purpose: Ultrahigh-field MRI (UHF-MRI) with an in-plane spatial resolution of less than 100 μm is known as MR microscopy (MRM). MRM provides highly resolved anatomical images and allows quantitative assessment of different tissue types using diffusion-weighted imaging (DWI). The aim of the present study was to evaluate the feasibility of combined in vivo anatomical and quantitative assessment of the developing chicken eye in ovo.Procedures: Thirty-eight fertilized chicken eggs were examined at 7.1 T (ClinScan, Bruker Biospin, Germany) acquiring a dataset comprising T2-weighted anatomical images, DWI, and diffusion tensor imaging. To reduce motion artifacts, the eggs were moderately cooled before and during MR imaging. Two eggs were imaged daily for the entire developmental period, and 36 eggs were examined pairwise at only one time point of the embryonic period. Development of the eye was anatomically and quantitatively assessed.Results: From the D5 embryonic stage (116-124 h), MRM allowed differentiation between lens and vitreous body. The lens core and periphery were first identified at D9. DWI allowed quantification of lens maturation based on a significant decrease in apparent diffusion coefficient values and course of fractional anisotropy. Repeated moderate cooling had no influence on the development of the chicken embryo.Conclusions: MRM allows in vivo assessment of embryonic development of the chicken eye in ovo without affecting normal development. The method provides anatomical information supplemented by quantitative evaluation of lens development using DWI. With increasing availability of ultrahigh-field MR systems, this technique may provide a noninvasive complementary tool in the field of experimental ophthalmology. [ABSTRACT FROM AUTHOR]

Introduction. Diabetic neuroosteoarthropathy (DNOAP) early symptoms are unspecific, mimicking general infectious symptoms and rendering a diagnosis challenging. Consequently, unfavourable outcomes occur frequently, with recurrent foot ulceration, infectious complications, and eventually amputation. Corneal confocal microscopy (CCM) of the subbasal nerve plexus (SNP) is used to detect early peripheral neuropathy in diabetic patients without diabetic retinopathy. This pilot study was designed to determine if specific SNP changes manifest in severe DNOAP in comparison to a healthy control group. Methods. This pilot study utilized a matched-pair analysis to investigate SNP changes by in vivo CCM for 26 patients (mean patient age 63.7 years, range 27 to 78) with severe DNOAP defined by condition after the need for reconstructive foot surgery (n=13) and a healthy control group (n=13). Corneal nerve fibre length (CNFL), nerve fibre density (CNFD), nerve branch density (CNBD), average weighted corneal nerve fibre thickness (CNFTh), nerve connecting points (CNCP), and average weighted corneal nerve fibre tortuosity (CNFTo) were assessed as well as the general clinical status, diabetic status, and ophthalmologic basic criteria. Results. In vivo CCM revealed significantly reduced SNP parameters in the DNOAP group for CNFL (p=0.010), CNFD (p=0.037), CNBD (p=0.049), and CNCP (p=0.012) when compared to the healthy control group. Six patients (46%) of the DNOAP group suffered from diabetic retinopathy and none of the control group. Conclusions. This pilot study revealed a rarefication of SNP in all measured parameters in patients with severe DNOAP. We see a potential value of CCM providing a SNP-based biomarker for early stages of DNOAP prior to the development of any foot deformities that needs to be evaluated in further studies. This trial is registered with German Clinical Trials Register (DKRS) DRKS00007537. [ABSTRACT FROM AUTHOR]

Optical coherence tomography (OCT) enables noninvasive high-resolution 3D imaging of the human retina, and thus plays a fundamental role in detecting a wide range of ocular diseases. Despite the diagnostic value of OCT, managing and analyzing resulting data is challenging. We apply two visual analysis strategies for supporting retinal assessment in practice. First, we provide an interface for unifying and structuring data from different sources into a common basis. Fusing that basis with medical records and augmenting it with analytically derived information facilitates thorough investigations. Second, we present a tailored visual analysis tool for presenting, emphasizing, selecting, and comparing different aspects of the attributed data. This enables free exploration, reducing the data to relevant subsets, and focusing on details. By applying both strategies, we effectively enhance the management and the analysis of retinal OCT data for assisting medical diagnoses. Domain experts applied our solution successfully to study early retinal changes in patients suffering from type 1 diabetes mellitus. [ABSTRACT FROM AUTHOR]

Following injury, corneal stromal keratocytes transform into repair-phenotype of activated stromal fibroblasts (SFs) and participate in wound repair. Simultaneously, ongoing bi-directional communications between corneal stromal-epithelial cells also play a vital role in mediating the process of wound healing. Factors produced by stromal cells are known to induce proliferation, differentiation, and motility of corneal epithelial cells, which are also subsequently the main processes that occur during wound healing. In this context, the present study aims to investigate the effect of SFs conditioned medium (SFCM) on corneal epithelial cell function along with substance P (SP). Antibody microarrays were employed to profile differentially expressed cell surface markers and cytokines in the presence of SFCM and SP. Antibody microarray data revealed enhanced expression of the ITGB1 in corneal epithelial cells following stimulation with SP whereas SFCM induced abundant expression of IL-8, ITGB1, PD1L1, PECA1, IL-15, BDNF, ICAM1, CD8A, CD44 and NTF4. All these proteins have either direct or indirect roles in epithelial cell growth, movement and adhesion related signaling cascades during tissue regeneration. We also observed activation of MAPK signaling pathway along with increased expression of focal adhesion kinase (FAK), paxillin, vimentin, β-catenin and vasodilator-stimulated phosphoprotein (VASP) phosphorylation. Additionally, epithelial-to-mesenchymal transition (EMT) regulating transcription factors Slug and ZEB1 expression were enhanced in the presence of SFCM. SP enriched the expression of integrin subunits α4, α5, αV, β1 and β3 whereas SFCM increased α4, α5, αV, β1 and β5 integrin subunits. We also observed increased expression of Serpin E1 following SP and SFCM treatment. Wound healing scratch assay revealed enhanced migration of epithelial cells following the addition of SFCM. Taken together, we conclude that SFCM-mediated sustained activation of ZEB1, Slug in combination with upregulated migration-associated integrins and ERK (Extracellular signal-regulated kinase)-FAK-paxillin axis, may lead to induce type 2 EMT-like changes during corneal epithelial wound healing. [ABSTRACT FROM AUTHOR]

Purpose/Aim of the study: A recently proposed technique enables the generation of continuously increasing mosaic images of the corneal sub-basal nerve plexus (SNP) using in vivo corneal confocal microscopy (CCM). The aim of the present study was to investigate the progression of the corneal nerve fiber length (CNFL) measured in the growing mosaic images with regard to their increasing area. Materials and Methods: Five large datasets from three healthy volunteers were examined using the proposed CCM technique. Intermediate mosaic images were created and assessed for CNFL. Results: The measured CNFL progression shows both over- and underestimation of the CNFL for small observed areas. Increasing the mosaic image area stabilizes the CNFL values and reduces the moving variance in all five datasets. The relative deviation of means from values of first and second examination of two of the subjects shows high differences for an observed area of <1.5 mm2. Conclusions: The present examination provides two measures to quantify different area-dependent aspects of the CNFL measured in an expanding mosaic image. The moving variance measures how stable the CNFL can be considered at a certain mosaic size. The relative deviation of means from two repeated CCM examinations on the other hand gives some indication on the level of reliability that can be expected from the measured CNFL. The progression of CNFL in the examined datasets manifests a potentially very high variability for mosaic sizes of less than about 1.5 mm2. Above that size, CNFL progression and the intra-patient relative deviations both stabilize significantly in all five datasets. The results of the present examination suggest a recommendation for a minimum sampled area of the central SNP of 1.5 mm2for reliable and meaningful measurement of CNFL. [ABSTRACT FROM PUBLISHER]

Corneal confocal microscopy (CCM) has revealed reduced corneal nerve fiber (CNF) length and density (CNFL, CNFD) in patients with diabetes, but the spatial pattern of CNF loss has not been studied. We aimed to determine whether spatial analysis of the distribution of corneal nerve branching points (CNBPs) may contribute to improving the detection of early CNF loss. We hypothesized that early CNF decline follows a clustered rather than random distribution pattern of CNBPs. CCM, nerve conduction studies (NCS), and quantitative sensory testing (QST) were performed in a cross-sectional study including 86 patients recently diagnosed with type 2 diabetes and 47 control subjects. In addition to CNFL, CNFD, and branch density (CNBD), CNBPs were analyzed using spatial point pattern analysis (SPPA) including 10 indices and functional statistics. Compared to controls, patients with diabetes showed lower CNBP density and higher nearest neighbor distances, and all SPPA parameters indicated increased clustering of CNBPs (all P<0.05). SPPA parameters were abnormally increased >97.5th percentile of controls in up to 23.5% of patients. When combining an individual SPPA parameter with CNFL, ≥1 of 2 indices were >99th or <1st percentile of controls in 28.6% of patients compared to 2.1% of controls, while for the conventional CNFL/CNFD/CNBD combination the corresponding rates were 16.3% vs 2.1%. SPPA parameters correlated with CNFL and several NCS and QST indices in the controls (all P<0.001), whereas in patients with diabetes these correlations were markedly weaker or lost. In conclusion, SPPA reveals increased clustering of early CNF loss and substantially improves its detection when combined with a conventional CCM measure in patients with recently diagnosed type 2 diabetes. [ABSTRACT FROM AUTHOR]

Small fiber neuropathy is one of the most common and painful long-term complications of diabetes mellitus. Examination of the sub-basal corneal nerve plexus is a promising surrogate marker of diabetic neuropathy. To investigate the efficacy, reliability and reproducibility of in vivo corneal confocal microscopy (IVCCM), we used thy1-YFP mice, which express yellow fluorescence protein (YFP) in nerve fibers. 4 weeks after multiple low-dose injections of streptozotocin, thy1-YFP mice showed manifest diabetes. Subsequent application of insulin-releasing pellets for 8 weeks resulted in a significant reduction of blood glucose concentration and HbA1c, a significant increase in body weight and no further increase in advanced glycation end products (AGEs). IVCCM, carried out regularly over 12 weeks and analyzed both manually and automatically, revealed a significant loss of corneal nerve fiber length (CNFL) during diabetes manifestation and significant recovery after insulin therapy. Ex vivo analyses of CNFL by YFP-based microscopy confirmed the IVCCM results (with high sensitivity between manual and automated approaches) but demonstrated that the changes were restricted to the central cornea. Peripheral areas, not accessible by IVCCM in mice, remained virtually unaffected. Because parallel assessment of intraepidermal nerve fiber density revealed no changes, we conclude that IVCCM robustly captures early signs of diabetic neuropathy. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study is to determine age-related morphological changes in the corneal subbasal nerve plexus (SNP) in two inbred mouse strains. Materials and methods: The corneal SNP was investigated by in vivo confocal laser scanning microscopy (CLSM) in 0.5-, 1-, 1.5-, and 2-year-old C57BL/6J mice and in 0.5- and 1-year-old BALB/c mice (n= 4 per age category and strain; 10 images per mouse). Fixed corneal samples from C57BL/6J mice were also analyzed after PGP9.5 staining. Nerve fiber density (NFD) was determined using the semi-automated NeuronJ program. In addition, a new custom-designed, fully automated computerized technique based on oriented multiscale matched filtering was tested to objectify and accelerate image analysis. Results: C57BL/6J mice showed low NFD (11.7 ± 0.5 mm/mm2). Aging from 0.5 to 1, 1.5, and 2 years resulted in significant reductions in subbasal NFD by 34%, 49%, and 66%, respectively. The decline in nerve fibers revealed by in vivo CLSM together with NeuronJ quantification was confirmed by ex vivo immunohistochemical analyses. Subbasal NFD in BALB/c mice (30.0 ± 1.4 mm/mm2) was 3-fold higher than in C57BL/6J mice. Aging from 0.5 to 1 year resulted in a significant 17% reduction in NFD. With the automated approach, NFD of 22.6 ± 2.9 mm/mm2and a 45% reduction during aging was determined from the same images. Conclusions: An age-related reduction in subbasal corneal nerve fibers was observed. The differing extent of reduction in the two mouse strains may be accounted for by genetic factors. Automated NFD quantification of corneal nerve fibers in mice appears to be a useful, reliable, objective, and time-saving tool. [ABSTRACT FROM AUTHOR]

The application of two-photon polymerization and molding for the fabrication of a multifocal diffractive-refractive lens operating in water is studied. The fabricated lens is of aspheric shape and combines diffractive and refractive parts in a single element to generate three foci. The lens performance is characterized by visualization of the beam propagation in a transparent basin filled with water containing fluorescein. The experimental measurements are in good agreement with the theoretical description. The obtained results are promising for the realization of trifocal intraocular lenses with predetermined light intensity distribution between the foci. [ABSTRACT FROM AUTHOR]

Purpose. Different IOL materials, particularly blue-light filtering materials, have different spectral transmittance characteristics. The color stimuli, which influence retinal receptors objectively, have consequently implications for color perception. We report on the quantitative determination of IOL-specific transmittance characteristics and present a method visualizing the resultant changes in color stimulus. Methods. A setup was realized to quantify IOL-absorption in a range of 390–780 nm. To visualize the influence of the different spectral transmittance characteristics an algorithm was developed, which converts RGB-pixel values of images into spectra, which performs the corresponding transmittance correction, reconverts to RGB, and reconstructs the image. IOLs of hydrophobic acrylate and hydrophilic acrylate with a hydrophobic surface in each case with/without blue-light filter were examined. Results. Assessment of the reference images verifies the suitability of the pipeline. Evaluation of the transmittance spectra reveals differences of material- and manufacturer-specifics, which are capable of inducing considerable changes in color perception, particularly in the blue color range and mixed colors involving blue. Conclusions. The developed technique provides an approach for determining IOL-specific transmittance behavior and subsequently its influence on the retinal color stimulus. Problems of altered color perception are occasionally reported after cataract surgery and these become obvious with the visualization procedure developed here. [ABSTRACT FROM AUTHOR]

Two-photon microscopy (TPM) allows high contrast imaging at a subcellular resolution scale. In this work, the microscopy technique was applied to visualize corneal structures in two mouse models (BALB/c and B6.Cg-Tg(Thy1-YFP)16Jrs/J) in vivo . In particular, the transgenic Thy1-YFP mice expressing the yellow fluorescent protein (YFP) in all motor and sensory neurons had been used for investigating the nerve fiber density in healthy and streptozotocin-diabetic mice. This model is clinically relevant since patients suffering from diabetes mellitus have a high risk to develop small fiber neuropathy. Nonlinear laser scanning microscopy displayed a reduction of nerve fiber density in streptozotocin-diabetic versus healthy mice and confirmed data obtained by confocal laser scanning microscopy (CLSM). In recent years, corneal CLSM was proved to be an appropriate non-invasive tool for an early diagnosis of diabetic neuropathy. Nevertheless, validation of the CLSM method for the clinical routine is currently a matter of investigation and requires confirmation by further studies and complementary techniques. Thus, the present study provides further evidence of corneal confocal microscopy as a promising technique for non-invasive detection of diabetic neuropathy. Information derived from these experiments may become clinically relevant and help to develop new drugs for treatment of diabetic neuropathy. [ABSTRACT FROM AUTHOR]