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The functional restoration of Brown class III maxillary defects is a challenging endeavour in oral and maxillofacial surgery. Conventional reconstruction techniques with osseous free flaps have certain limitations, such as the need for multiple operations and greater patient morbidity. This study introduces a single-stage computer-assisted approach for tumour resection and functional restoration of these defects using titanium mesh, zygomatic implants, and a vascularized anterolateral thigh flap (ALTF). Virtual surgical planning was used to simulate tumour resection, titanium mesh placement, and zygomatic implant insertion. Surgery was performed under the guidance of mixed reality and surgical navigation. The tumour was resected by total hemimaxillectomy, and the reconstruction was performed using a pre-bent patient-specific titanium mesh for the orbital floor and two zygomatic implants placed and exposed through tunnels in an ALTF. The ALTF survived without any perioperative complications. A fixed prosthesis with built-in titanium frame was delivered 4 months postoperatively. At the 1-year follow-up, there was no tumour recurrence, the implants were osseointegrated, and aesthetics and masticatory function were satisfactory. An occlusal force of 155 N was attained on the reconstructed side, compared to 127 N on the non-surgical side. [ABSTRACT FROM AUTHOR]

The study aimed to evaluate and discuss the use of an innovative PSI made of porous hydroxyapatite, with interconnected porosity promoting osteointegration, called MyBone Custom® implant (MBCI), for maxillofacial bone reconstruction. A multicentric cohort of 13 patients underwent maxillofacial bone reconstruction surgery using MBCIs for various applications, from genioplasty to orbital floor reconstruction, including zygomatic and mandibular bone reconstruction, both for segmental defects and bone augmentation. The mean follow-up period was 9 months (1–22 months). No infections, displacements, or postoperative fractures were reported. Perioperative modifications of the MBCIs were possible when necessary. Additionally, surgeons reported significant time saved during surgery. For patients with postoperative CT scans, osteointegration signs were visible at the 6-month postoperative follow-up control, and continuous osteointegration was observed after 1 year. The advantages and disadvantages compared with current techniques used are discussed. MBCIs offer new bone reconstruction possibilities with long-term perspectives, while precluding the drawbacks of titanium and PEEK. The low level of postoperative complications associated with the high osteointegration potential of MBCIs paves the way to more extensive use of this new hydroxyapatite PSI in maxillofacial bone reconstruction. [Display omitted] [ABSTRACT FROM AUTHOR]

To clinically and radiographically evaluate patient-specific titanium meshes via a trans -antral approach for correction of enophthalmos and orbital volume in patients with recent unilateral orbital floor fracture. Seven patients with unilateral orbital floor fractures received patient-specific titanium meshes that were designed based on a mirror-image of the contralateral intact orbit. The patient-specific implants (PSIs) were inserted via a trans -antral approach without endoscopic assistance. The patients were evaluated clinically for signs of diplopia and restricted gaze as well as radiographically for enophthalmos and orbital volume correction. Diplopia was totally resolved in two of the three patients who reported diplopia in the upward gaze. Whereas enophthalmos significantly improved in all but two patients, with a mean value of 0.2229 mm postoperatively compared to 0.9914 mm preoperatively. CT scans showed excellent adaptation of the PSIs to the orbital floor with a mean reduction of the orbital volume from 29.59 cc to 27.21 cc, a mean of 0.6% smaller than the intact orbit. It can be concluded that the proposed PSI can offer good reconstruction of the orbital floor through an isolated intraoral transantral approach with minimal complications. It could of special benefit in extensive orbital floor fractures. [ABSTRACT FROM AUTHOR]

Two-line element sets (TLE) released by the 18th Space Control Squadron are the most complete source of information for space situational awareness in the public domain. They are used in a wide range of contexts that include navigation of nanosatellites and ground communication. However, the TLE data are known for having significant bias and errors. Predicting the bias of TLE can be a way to correct them automatically and hence optimize the systems that rely on them at low cost, for instance for reentry calculations and mission analysis. This paper shows the performance of a neural network trained on more than 4500 inactive resident space objects (RSO) on 10 months of orbital data, on all types of orbits. It is shown that the state vector errors are corrected by at least 40% for 70% of the TLE and that the residual error distributions are well described by a Student's t-distribution for which covariance elements are defined consistently. The performance of the trained neural network are shown to be similar for multiple active satellites. [ABSTRACT FROM AUTHOR]

Malignant peripheral nerve-sheath tumor (MPNST) is an extremely rare sarcoma of the nasal cavity and paranasal sinuses. Non-specific clinical and radiological presentation and challenging histological diagnosis make it little known by physicians. We describe a case of maxillary sinus MPNST, following CARE guidelines. A 62-year-old woman consulted for swelling of the right cheek and hard palate with several months' progression. CT and MRI revealed a tissue mass in the right maxillary sinus with osteolysis of the orbital and maxillary floors, hard palate and lateral and medial walls of the maxillary sinus. Biopsy confirmed diagnosis of low-grade MPNST. After total resection and 60 Gy adjuvant radiotherapy, 2-year follow-up showed no signs of recurrence. MPNST in the nasal cavity and paranasal sinuses is very rare. Because of a high risk of recurrence, wide resection should be implemented, possibly completed by radiotherapy if resection cannot be complete because of proximity to at-risk structures. [ABSTRACT FROM AUTHOR]

Endoscopic transnasal approaches (ETAs) to the ventrolateral skull base are commonly classified according to coronal planes or anatomical structures. Our goal is to simplify the description of the ETA to lateral skull base regions in a sequential dissection with correlation to computed tomography, helping in preoperative planning and efficient surgical exposure, and exposing the surgical anatomy limitations. Five freshly injected cadaver heads were dissected using an extended ETA to the lateral skull base. Each specimen underwent a high-resolution computed tomography scan. A classification of the lateral skull base based on well-defined zones was proposed. We divided the lateral target into four different zones, in a craniocaudal orientation: zone 1 is the space lying between the orbital floor superior and the level of the sellar floor inferior, zone 2 is on the coronal plane, located between the level of the sellar floor and the vidian canal, zone 3 is the area lateral to the anterior limb of the petro-occipital fissure, located between the vidian canal and the carotid canal, and zone 4 is the space located between the carotid canal and the extracranial opening of the hypoglossal canal, lateral to the anterior part of the posterior limb of petro-occipital fissure. Multiple previous works have described and classified the coronal plane and its lateral extensions. Our classification system for the proposed lateral zones enables preoperative planning to select a suitable approach. The craniocaudal orientation facilitates the understanding of surgical corridors and tailored exposure. [ABSTRACT FROM AUTHOR]

In this retrospective case series, patients undergoing surgery to treat isolated orbital floor fractures were morphometrically analyzed. Cloud Compare was used to compare mesh positioning with a virtual plan, using the distance-to-nearest-neighbor method. To assess the accuracy of mesh positioning, a mesh area percentage (MAP) parameter was introduced and three distance ranges were defined as the outcome measures: the 'high-accuracy range' included MAPs at a distance of 0–1 mm from the preoperative plan; the 'intermediate-accuracy range' included MAPs at a distance of 1.1–2 mm from the preoperative plan; the 'low-accuracy range' included MAPs at a distance of >2 mm from the preoperative plan. To complete the study, morphometric analysis of the results was combined with clinical judgment ('excellent', 'good', or 'poor') of mesh positioning by two independent blind observers. In total, 73 of 137 orbital fractures met the inclusion criteria. In the 'high-accuracy range' the mean, minimum, and maximum MAP values were 64%, 22%, and 90%, respectively. In the 'intermediate-accuracy range', the mean, minimum, and maximum values were 24%, 10%, and 42%, respectively. In the 'low-accuracy range', the values were 12%, 1%, and 48%, respectively. Both observers classified 24 cases of mesh positioning as 'excellent', 34 as 'good', and 12 as 'poor'. Within the limitations of the study, it seems that virtual surgical planning and intraoperative navigation has the potential to add quality to the repair of the orbital floor and, therefore, should be taken into consideration whenever appropriate. [ABSTRACT FROM AUTHOR]

Lower eyelid malposition (LEM) is a common sequela after orbital fracture reconstruction. This study aimed to analyse the development of LEM, specifically ectropion and entropion, following primary orbital fracture reconstruction, to identify predictive factors for LEM, and to assess the effect of the eyelid complication on patients' daily lives. The retrospective cohort comprised patients who had undergone orbital floor and/or medial wall fracture reconstruction for recent trauma. Demographics, fracture type and site, surgery and implant-related variables, follow-up time and number of visits, type and severity of LEM, subsequent surgical correction, and patient satisfaction, were analysed. The overall occurrence of LEM was 8%, with ectropion in 6% and entropion in 2% of patients. Older age, complex fractures, transcutaneous approaches, preoperative traumatic lower lid wounds, and implant material were associated with the development of LEM. Of all patients, 3% needed surgical correction of LEM. Six of the 13 patients (46%) who developed LEM required surgical correction. The transconjunctival approach and patient-specific implants should be preferred, especially in elderly patients and those with more complex fractures. LEM often requires subsequent surgical correction, and the treatment period is substantially prolonged, with multiple extra visits to the clinic. [ABSTRACT FROM AUTHOR]

The Superior Ophthalmic Vein (SOV) is the largest vein of the orbit and represents an important orbital venous drainage pathway. SOV is well identifiable on CT and MRI, and its alterations may be a clue for differential diagnosis. In this pictorial work we illustrate the most frequent conditions in which SOV appearance may be influenced by various pathologies, providing a pictorial guide for imaging interpretation. • The Superior Ophthalmic Vein (SOV) represents an important orbital venous drainage pathway • SOV is well evaluated through coronal and axial planes on Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) • A diameter of more than 2.5 mm is to be considered a reasonable cut-off for SOV dilation • SOV enlargement may be associated with various conditions (increased intracranial pressure, intubation, thrombosis, vascular malformations, pseudotumor orbitae, neoplasm, trauma, stroke). [ABSTRACT FROM AUTHOR]

Primary intraocular tumours are infrequent in birds. A 2-year-old male Lady Gouldian finch (Erythrura gouldiae) originally presented to the referring veterinarian after the owner noticed mild swelling of the right eye. After the eye had enlarged rapidly and bulged from the orbit, the bird was seen at the referral hospital. Enucleation was attempted but the bird died after sedation. The eye was removed and, on sectioning, a mass was seen primarily in the vitreous chamber with extension through the sclera to the retrobulbar area. After routine histology, immunohistochemistry and electron microscopy, the mass was diagnosed as an embryonal tumour of probable retinal origin. This type of tumour has rarely been documented in birds and we could find no references to any report in Estrildidae. [ABSTRACT FROM AUTHOR]

Thyroid eye disease (TED) is an autoimmune condition affecting the orbit and the eye with its adnexa, often occurring as an extrathyroidal complication of Graves' disease (GD). Orbital inflammatory infiltration and the stimulation of orbital fibroblasts, triggering de novo adipogenesis, an overproduction of hyaluronan, myofibroblast differentiation, and eventual tissue fibrosis are hallmarks of the disease. Notably, several redox signaling pathways have been shown to intensify inflammation and to promote adipogenesis, myofibroblast differentiation, and fibrogenesis by upregulating potent cytokines, such as interleukin (IL)-1β, IL-6, and transforming growth factor (TGF)-β. While existing treatment options can manage symptoms and potentially halt disease progression, they come with drawbacks such as relapses, side effects, and chronic adverse effects on the optic nerve. Currently, several studies shed light on the pathogenetic contributions of emerging factors within immunological cascades and chronic oxidative stress. This review article provides an overview on the latest advancements in understanding the pathophysiology of TED, with a special focus of the interplay between oxidative stress, immunological mechanisms and environmental factors. Furthermore, cutting-edge therapeutic approaches targeting redox mechanisms will be presented and discussed. [Display omitted] • Thyroid Eye Disease is an autoimmune condition that poses a threat to vision and can result in disfigurement. • The disease's pathophysiology is rooted in a complex interplay of autoimmune cascade and redox signaling networks. • Tobacco smoke is a significant risk factor for thyroid eye disease, promoting hypoxia, oxidative stress, and inflammation. • Antioxidants, such as selenium, may have beneficial effects on TED by reducing oxidative stress and inflammation. [ABSTRACT FROM AUTHOR]

Uveitis is among the leading causes of visual loss in the working age population. In noninfectious uveitis, corticosteroids are the first line therapy. We sought to review systematically the evidence regarding the regional corticosteroid delivery modalities in the treatment of noninfectious uveitis. A 5-database search (Pubmed, ISI Web of Science, Cochrane, ClinicalTrials.gov, and Scopus) was performed from inception to February, 2021. Nineteen studies with a total of 1,935 eyes of 1,753 patients were selected from 8,922 abstracts retrieved by the initial search. The most frequently compared regimens were intravitreal triamcinolone acetonide injection and orbital floor triamcinolone acetonide injection (2 studies), intravitreal triamcinolone acetonide injection and posterior sub-Tenon triamcinolone acetonide injection (2 studies), and posterior sub-Tenon triamcinolone acetonide injection with the intravitreal dexamethasone implant (2 studies). Our results show that the intravitreal injection of corticosteroids is more effective, but is associated with more adverse events, than periocular injection. Some evidence supports the use of subconjunctival triamcinolone acetonide over intravitreal/periocular triamcinolone acetonide. Moreover, the overall results of 0.59 mg dosage of the intravitreal fluocinolone acetonide implant were superior to those from the 2.1 mg dose. The evidence, however, is not robust, and further studies with standardized outcomes are warranted. [ABSTRACT FROM AUTHOR]

In patients treated by orbital wall decompression for endocrine orbitopathy (EO) there is limited evidence on the effect of orbital wall resections. Thus, the aim of this study was to evaluate the effect of one, two, and three-wall resections on orbital parameters to determine if any such correlations exist. Preoperative and postoperative data from all patients at a tertiary care centre who underwent decompression surgery from 2010 - 2020 were digitally analysed. The effect of the number and area of resected walls on orbital area, orbital volume, and Hertel value, and the effect of lateral rim advancement (LARA) were determined. A total of 131 orbital areas showed an increase from a mean (SD) preoperative area of 42.0 (4.6) cm2 to 47.3 (6.1) cm2 postoperatively (p<0.001). In total, the mean (SD) area of osseous wall removed in all patients was 6.2 (1.7) cm2 at the lateral orbit (n = 129), 6.7 (2.3) cm2 at the orbital floor (n = 123), and 5.8 (1.8) cm2 at the medial orbital wall (n =30). The mean (SD) orbital volume increased by 6.0 (3.0) cm3 after decompression. There was also a significant reduction in exophthalmos of 7.3 (3.2) mm (from 25.2 (3.9) to 17.9 (3.5), p<0.001). LARA was performed in 50 patients. Changes in volume and area, and reduction in exophthalmos were not significantly different with or without LARA. The postoperative effects of orbital wall resection are predictable and exhibit a relation with six units of change. Two-wall resection is the most common intervention. [ABSTRACT FROM AUTHOR]

The purpose of this systematic review was to critically analyse the recent literature and present the state of the art in customised reconstruction of orbital fractures. Three electronic databases and manual search approaches were used to identify relevant articles. Only controlled clinical studies were included. Primary outcome was defined as the status of recovery (complete/partial functional, and aesthetic disturbances). The benefit of intrasurgical navigation should be described. The secondary outcome was defined as the time of surgery, post-surgical events, and hospitalisation. Of the 552 records identified, eight met the inclusion criteria. Post-surgical results regarding recovery were superior in the customised group, and were comparable to the control group in five studies. The time of surgery was shorter in the customised groups, and liquid infusion and time of hospitalisation were reduced. Four studies documented more accurate reconstruction with the use of navigation. All the studies presented at least one bias, and considerable heterogeneity was evaluated. This review found that the use of customised meshes in combination with surgical navigation resulted in more accurate reconstruction. A significant reduction in surgical time was revealed. [ABSTRACT FROM AUTHOR]

Computed tomography (CT) is commonly used for the diagnosis, treatment planning, and prognosis of pure orbital fractures of the orbital floor and medial wall. The aim of this study was to systematically review the current literature in order to establish an overview of CT parameters relevant to the choice of treatment and (long-term) clinical outcome for patients treated operatively and conservatively. The PRISMA guidelines were followed. Databases were searched using the terms 'orbital fracture' and 'computed tomography'. Studies evaluating the relationship between CT parameters and the treatment decision or clinical outcome (enophthalmos, diplopia, and/or limitation of ocular movement) were included. The search yielded 4448 results of which 31 were included (except for three, all were retrospective). The systematic use of CT imaging in orbital fractures of the floor and the medial wall can be of great value in the treatment decision and prediction of (long-term) clinical outcomes for both conservatively and surgically treated patients. The following parameters were found to be the most relevant: fracture size, fracture location, orbital volume, soft tissue involvement, and craniocaudal dimension. Although some show great individual potential, it is likely that incorporating all parameters into an algorithm will provide the best predictive power and thus would be the most practically applicable tool. [ABSTRACT FROM AUTHOR]

The study aims to depict the radiological features of Cov-ROCM, depict the common routes of spread to orbits and intracranial compartment and look for an association of the risk factors with radiological severity of the disease. 96 patients who had COVID-19 infection in the past 3 months and were diagnosed with ROCM underwent CECT PNS examinations which were assessed by two experienced radiologists. They were divided into three groups based on the intraorbital and intracranial involvement and were correlated with various risk factors. The incidence of bony erosions which was the commonest finding (75%) was double in Cov-ROCM than the ROCM cases of pre COVID era (33–40%). The most common route of spread to orbit was through angioinvasion(52%) with intact orbital walls; and intracranial extension was via erosion of the cribriform plate(52%). Sphenoid sinus involvement is strongly associated with intracranial and intraorbital involvement.(p-value =.0004). History of longer ICU stays and being on mechanical ventilation as a part of COVID management is associated with aggressive disease pattern(p-value =.002). Similarly, poor glycaemic control signified by raised HbA1c levels showed statistically significant correlation with severe Cov-ROCM(intraorbital/intracranial extension) (p-value =.040). Amidst the COVID pandemic, it is pertinent to look at bony erosions in case of any sinusitis, especially bony maxillary walls and the turbinates. The intraorbital compartment must be viewed thoroughly even in the absence of bony erosions due to the angioinvasive nature of these fungi. Aggressive follow-up for patients with ICU stays for COVID and for glycaemic control would help reduce the morbidity. • Bony erosions are much more prevalent in COVID-associated ROC Mucormycosis • Commonest route of spread to the orbits was via angioinvasion. Hence, Orbital disease must always be looked for even with intact bony walls • Sphenoid sinus involvement is strongly associated with intracranial and intraorbital involvement. • History of longer ICU stays and mechanical ventilation as a part of COVID management predisposed to aggressive disease pattern • Higher HbA1c levels strongly correlated with aggressive disease pattern [ABSTRACT FROM AUTHOR]

• The haptic measurement of spatial orientation is affected by a hand bias. • The hand bias is a sensory bias related to the haptic nature of the task. • The hand bias is related to hand-in-body information (right vs left hand). • The hand bias is related to hand-in-space information (haptic stimulus placement). The primary sensory modality for probing spatial perception can vary among psychophysical paradigms. In the subjective visual vertical (SVV) task, the brain must account for the position of the eye within the orbit to generate an estimate of a visual line orientation, whereas in the subjective haptic vertical (SHV) task, the position of the hand is used to sense the orientation of a haptic bar. Here we investigated whether a hand sensory bias can affect SHV measurement. We measured SHV in 12 subjects (6 left-handed and 6 right-handed) with a forced-choice paradigm using their left and right hands separately. The SHV measurement was less accurate than the SVV measurements (−0.6 ± 0.7) and it was biased in the direction of the hand used in the task but was not affected by handedness; SHV left hand −6.8 ± 2.1° (left-handed −7.9 ± 3.6°, right-handed −5.8 ± 2.5°) and right hand 9.8 ± 1.5° (left-handed 7.4 ± 2.2°, right-handed 12.3 ± 1.8°). SHV measurement with the same hand was also affected by the haptic bar placement on the left or right side versus midline, showing a side effect (left vs midline −2.0 ± 1.3°, right vs midline 3.8 ± 1.7°). Midline SHV measures using the left and right hands were different, confirming a laterality effect (left hand −4.5 ± 1.7°, right hand 6.4 ± 2.0°). These results demonstrate a sensory bias in SHV measurement related to the effects of both hand-in-body (i.e., right vs left hand) and hand-in-space positions. Such modality-specific bias may result in disparity between SHV and SVV measurements, and therefore cannot be generalized to vertical or spatial perception. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the value of intraoperative conebeam computed tomography (CBCT) imaging in the treatment of zygomaticomaxillary complex (ZMC) fractures. A prospective single center cohort study was performed. Included were consecutive patients who underwent surgery for a unilateral ZMC fracture. An intraoperative CBCT scan was performed after reduction of the ZMC fracture. Revision reduction was performed of the ZMC and/or orbital floor (OF) on indication. The preoperative and postoperative asymmetry of the outer surface of the ZMC was measured on digital 3D-models of CBCT scans, using a mirroring and surface-based matching technique. The postoperative asymmetry of the ZMC in the study group was compared to the asymmetry of the ZMC in the control group with healthy individuals. A total of 38 patients with a unilateral ZMC fracture were included. The mean postoperative asymmetry in the study group (1.67 mm, SD 0.89) was less than the mean preoperative asymmetry (2.69 mm, SD 0.95) (paired samples T-test p < 0.01) but showed no statistically significant difference with the mean asymmetry in the healthy control group (1.40 mm, SD 0.54) (independent samples T-test p = 0.31). Revision reduction of the ZMC and/or OF fracture had been performed in 11 cases after malalignment was noted on the intraoperative CBCT. The indication for intraoperative revision reduction was associated with comminuted ZMC fractures and/or fractures with indication for OF reduction (Pearson Chi Square p < 0.01). Within the limitations of the study, intraoperative CBCT imaging seemed to have a positive influence on ZMC fracture treatment, especially in the case of comminuted ZMC fractures and/or fractures with indication for OF treatment. [ABSTRACT FROM AUTHOR]

This study comprises a dynamic finite element (FE) analysis of the mechanisms of orbital trauma, specifically buckling and hydraulic theories. A digital model of the orbital cavity - including the eyeball, fatty tissue, extraocular muscles, and the bone orbit – was created from magnetic resonance imaging and computed tomographic data from a real patient. An impactor hit the FE model following two scenarios: one was a hydraulic mechanism for direct impact to the eyeball and the other a buckling mechanism for direct impact over the infraorbital rim. The first principal stress was calculated to determine the stress distribution over the orbital walls. The FE model presented more than 900,000 elements and time of simulation was 4.8 milliseconds (ms) and 0.6 ms, for the hydraulic and buckling mechanisms, respectively. The stress distribution in the hydraulic mechanism affected mainly the medial wall with a high stress area of 99.08 mm2, while the buckling mechanism showed a high stress area of 378.70 mm2 in the orbital floor. The presence of soft tissue absorbed the energy, especially in the hydraulic mechanism. In conclusion, the applied method of segmentation allowed the construction of a complete orbital model. Both mechanisms presented results that were similar to classic experiments. However, the soft tissue in the hydraulic mechanism absorbed the impact, demonstrating its role in orbital pathophysiology. [ABSTRACT FROM AUTHOR]

This retrospective study evaluates the occurrence and frequency of different fracture patterns in a series of computed tomography (CT) scans in terms of the AOCMF Trauma Classification (TC) orbit module and correlates the assigned defects with measurements of the fracture area in order to get an approximate guideline for fracture size predictions on the basis of the classification. CT scans of patients with orbital floor fractures were evaluated using the AOCMFTC to determine the topographical subregions. The coding consisted of: W = orbital wall, 1 = anterior orbit, 2 = midorbit, i = inferior, m = medial. The 3-dimensional surface area size of the fractures was quantified by the "defect body" method (Brainlab, Munich, Germany). The fracture area size and its confidence and prediction interval within each topographical subregion was estimated by regression analysis. A total of 137 CT scans exhibited 145 orbital floor fractures, which were combined with 34 medial orbital wall fractures in 31 patients. The floor fractures – W1(i)2(i) (n = 86) and W1(i) (n = 19) were the most frequent patterns. Combined floor and medial wall fractures most frequently corresponded to the pattern W1 (im)2 (im) (n = 15) ahead of W1 (im) 2(i) (n = 10). The surface area size ranged from 0.11 cm2 to 6.09 cm2 for orbital floor and from 0.29 cm2 to 5.43 cm2 for medial wall fractures. The prediction values of the mean fracture area size within the subregions were computed as follows: W1(i) = 2.25 cm2, W2(i) = 1.64 cm2, W1(i)2(i) = 3.10 cm2, W1(m) = 1.36 cm2, W2(m) = 1.65 cm2, W1(m)2(m) = 2.98 cm2, W1 (im) = 3.35 cm2, W1 (im) 2(i) = 4.63 cm2, W1 (im)2(m) = 4.06 cm2 and W1 (im)2 (im) = 7.16 cm2. The AOCMFTC orbital module offers a suitable framework for topographical allocation of fracture patterns inside the infero-medial orbital cavity. The involvement of the subregions is of predictive value providing estimations of the mean 3-D fracture area size. [ABSTRACT FROM AUTHOR]

Background: Lateral canthotomy is a vision-saving procedure. However, the low incidence of orbital compartment syndrome and the expense of simulators to practice this procedure can lead to low confidence and delays in the performance of the procedure by emergency physicians.Discussion: We used a simple, inexpensive, easily assembled eye model for lateral canthotomy education at a residency program and a national conference obtaining feedback from simulation participants. Residents rated procedure laboratories that included the lateral canthotomy model as 4.9 to 5 (on a 5-point Likert scale, with 5 being the best score). National conference participants rated the model a 9 as a useful training model for practitioners on a 10-point Likert scale.Conclusion: This simple task trainer is practical, inexpensive, quickly assembled, and useful as a tool for practicing emergency medicine providers. [ABSTRACT FROM AUTHOR]

The altered orbital morphology of patients with Crouzon syndrome could have an impact on the planning of treatment in diverse populations, in spite of the confounding influences of different cranial suture synostosis. This study attempted to explore the differences in orbital characteristics between Asian, Caucasian patients with Crouzon syndrome, associated pansynostosis. Eighty-six preoperative computed tomograms (CT) were included (Asian Crouzon syndrome: n=10; Asian controls: n=24; Caucasian Crouzon syndrome: n=19; Caucasian controls: n=33) and measured using Mimics software (Materialise). Unique cephalometric measurements related to orbital morphology and position were designed. Crouzon syndrome and race both have interactive effects on protrusion of the globe (p=0.009) and medial horizontal angle (p=0.012) in the assessment of orbital morphology. They also interact in the width of the ethmoid sinus (p=0.009) and influence bilateral orbital relations. The anteroposterior orbital roof in Caucasian patients with Crouzon syndrome was shortened by 4.09 mm (p=0.002) compared with Caucasian controls. However, in Asian patients this dimension developed normally. The anteroposterior orbital floor was significantly reduced to a similar extent in both Asian and Caucasian Crouzon patients (both p<0.001). The visual axes in Caucasian patients with Crouzon showed more inferior rotation, by 4.38° (p=0.031) than they did in Caucasian controls, but did not achieve a statistically significant difference in other comparisons. The effect of Crouzon syndrome on orbital malformation and placement is influenced by race, especially structures related to the ethmoid sinus. Asian patients need greater infraorbital advancement for better correction of orbital proptosis and aesthetic benefits, but may require less fronto-orbital advancement than Caucasian patients. [ABSTRACT FROM AUTHOR]

Given the critical importance of intention recognition for non-cooperative space targets in enhancing spatial situational awareness and mitigating threats, this paper proposes a fast and accurate method based on a deep neural network for identifying the intentions. The proposed method takes the instantaneous single relative motion position and velocity of the non-cooperative target as input and calculates the probability of different potential intentions in real-time. To this end, the possible geometric configurations of relative motions of the targets are characterized and classified based on the Clohessy-Wiltshire (CW) equation, and intentions with respect to different types of motion are defined and grouped accordingly. To ensure the method's applicability for large range scenario, the required dataset in two-body dynamics is generated using satellite orbit extrapolation techniques. The deep neural network is trained on the dataset using back-propagation, and experiments are designed to evaluate the method's performance and the recognition accuracy reached 0.9289. The proposed method outperforms the dynamical characteristics matching-based method in terms of recognition accuracy, range of applicability, and time efficiency. The method has potential applications in spacecraft collision warning and orbital pursuit-evasion games, where rapid and accurate identification of non-cooperative target intentions is critical. [ABSTRACT FROM AUTHOR]

• Scaling and controlling the synaptic current is indispensable for integrating emerging non-volatile memories (eNVMs) into different grids and design choices of advanced CMOS Technology nodes. • The maximum current scaling down factor depends on the leakage current of the spiking neuron, and the saturation conditions of the current source of the transconductance amplifier. • The fan-in of the 28 nm FD-SOI analog spiking neuron depends on the eNVMs technology, the width and amplitude of input spikes, the firing threshold of the neuron, and the current scaling down factor. • The tunable and versatile current attenuator allows the integration of various eNVMs into 28 nm FD-SOI technology based analog spiking neural networks. In this work we report a study and a co-design methodology of an analog SNN crossbar output circuit designed in a 28 nm FD-SOI technology node that comprises a tunable current attenuator and a leak-integrate and fire neurons that would enable the integration of emerging non-volatile memories (eNVMs) for synaptic arrays based on various technologies including phase change (PCRAM), oxide-based (OxRAM), spin transfer and spin orbit torque magnetic memories (STT, SOT-MRAM). Circuit SPICE simulation results and eNVM experimental data are used to showcase and estimate the neurons fan-in for each type of eNVM considering the technology constraints and design trade-offs that set its limits such as membrane capacitance, supply voltage, leakage, etc. [ABSTRACT FROM AUTHOR]

The aim of this study was to identify the prevalence of the abnormal lateral interorbital distance (LIOD), micropthalmia or anopthalmia and incidence of hydrocephalus in frontoethmoidal encephalomeningocele (FEEM), and to identify the correlation between the external bony defects and a widened lateral orbital wall. FEEM patients who were treated in the Faculty of Medicine, Chiang Mai University between January 1, 2006, and December 31, 2016, were retrospectively reviewed from the medical records. We included the patients who had undergone head computed tomography (CT) of the facial bones. Exclusion criteria were any patients who had undergone prior facial surgery or had maxillofacial bone trauma before they underwent a CT scan, craniofacial disease such as facial clefts, frontonasal dysplasia, craniosynostosis, and inter-frontal encephalocele. Measurements were taken from the CT images to establish the diameter of the external bony defect, medial interorbital distance and lateral interorbital distance. The relationships between the external bony defect and widened LIOD were analyzed. Patients were divided into two groups: those with normal LIOD and those with wide LIOD. A total of 94 FEEM patients were evaluated. Thirteen patients (13.83%) had a wider than normal LIOD. The incidence of micropthalmia or anopthalmia was 9.57% and hydrocephalus was 45.74%. From a univariable model, there were no statistically significant differences in terms of patient characteristics between the LIOD groups, except for sex. The proportion of wide LIOD was higher in male patients (male vs female; 20.34% vs 2.86%, p = 0.027). The proportion between the external bony defect and the LIOD (EL ratio) associated with a wide LIOD was shown in a cutoff point of 23% (AuROC = 73.27%, 95%CI = 59.87%–86.66%). The multivariable analysis indicated factors associated with abnormal LIOD were an EL ratio of 23% (adjusted RR = 1.98, 95% CI = 1.58–2.51) and male sex (adjusted RR = 6.85, 95% CI = 2.00–23.55). There is an association between the EL ratio and widening of the LIOD. An EL ratio greater than 23% could be used to moderately predict a wide LIOD. A large external bony defect may be associated with lateral displacement of the orbit causing true hypertelorism. Therefore, orbital translocation must be considered in patients with a wide LIOD. [ABSTRACT FROM AUTHOR]

Neonatal retinal hemorrhage is a common finding in newborns, but the underlying mechanisms are not fully understood. A computational simulation was designed to study the events taking place in the eye and orbit when the head is compressed as the neonate passes through the birth canal. A finite element model of the eye, optic nerve sheath, and orbit was simulated and subjected to forces mimicking rises in intracranial pressure (ICP) associated with maternal contractions during normal vaginal delivery. Resulting changes in intraocular pressure (IOP), pressure in the optic nerve sheath, and stress within the sclera and retina were measured. During contractions, increased ICP was transmitted to the orbit, globe, and optic nerve sheath. IOP rose by 2.71 kPa near the posterior pole. Pressure at the center of the optic nerve sheath rose by 7.31 kPa and up to 9.30 kPa at its interface with the sclera. Stress in the retina was highest near the optic disk and reached 10.93, 10.99, and 13.28 kPa in the preretinal, intraretinal, and subretinal layers, respectively. Stress in the sclera peaked at 12.76 kPa. Increasing ICP associated with natural vaginal delivery increases intraorbital pressure, which applies stress to the retina. Associated retinal deformation may cause tearing of the retinal vasculature. Increased pressure within the optic nerve sheath may occlude the central retinal vein, resulting in outflow obstruction and subsequent rupture. Forces accumulated near the optic disk, likely accounting for the tendency of neonatal retinal hemorrhage to occur posteriorly.▪ [ABSTRACT FROM AUTHOR]

• Discussion of analytical orbit contraction methods and their shortcomings. • Extension of King-Hele method for semi-analytical propagation considering drag. • Introduction of a superimposed, parametric atmosphere model. • Verification against numerical quadrature and non-averaged integration. • Increase of accuracy considering atmosphere models with variable scale heights. Numerical integration of orbit trajectories for a large number of initial conditions and for long time spans is computationally expensive. Semi-analytical methods were developed to reduce the computational burden. An elegant and widely used method of semi-analytically integrating trajectories of objects subject to atmospheric drag was proposed by King-Hele (KH). However, the analytical KH contraction method relies on the assumption that the atmosphere density decays strictly exponentially with altitude. If the actual density profile does not satisfy the assumption of a fixed scale height, as is the case for Earth's atmosphere, the KH method introduces potentially large errors for non-circular orbit configurations. In this work, the KH method is extended to account for such errors by using a newly introduced atmosphere model derivative. By superimposing exponentially decaying partial atmospheres, the superimposed KH method can be applied accurately while considering more complex density profiles. The KH method is further refined by deriving higher order terms during the series expansion. A variable boundary condition to choose the appropriate eccentricity regime, based on the series truncation errors, is introduced. The accuracy of the extended analytical contraction method is shown to be comparable to numerical Gauss-Legendre quadrature. Propagation using the proposed method compares well against non-averaged integration of the dynamics, while the computational load remains very low. [ABSTRACT FROM AUTHOR]

Abstract Joint efforts and interdisciplinary approach are proper means to face the issue of global warming. An adequate response should be to employ state of the art scientific knowledge for the technology advancement, as well as for fostering new scientific insights. Together with resource efficiency, circular economy is getting in focus of researchers and consequently policymakers. Sustainable development is a multidisciplinary topic and interaction of energy, water and environment systems plays one of the central roles. Within the paradigm of circular economy, there is growing need for system integration where a by-product of one system can represent resource for the other. This review is dedicated to the 12th Conference on Sustainable Development of Energy, Water and Environment Sysmems, and discusses some latest developments in three main areas of sustainability themes: (i) Energy, (ii) Water and (iii) Environmental Systems. Examples of circular economy approach have been emphasized which improve economic efficiency of the whole chain and further decrease environmental burden, enabling cleaner production. Although integrative concept of energy, water and environmental systems is coming in the research focus, more effort is necessary for further integration of those systems, whereby increased complexity is going to be handled only by multidisciplinary, intersectoral scientific cooperation. [ABSTRACT FROM AUTHOR]

Abstract Assessment of ocular irritation risk is an international regulatory requirement in the safety evaluation of products. In response to this need, L'Oréal developed the SkinEthic™ Human Corneal Epithelium (HCE) Eye Irritation Test (EIT) that has been included in OECD Test Guideline 492. SkinEthic™ HCE EIT is able to correctly and reliably identify chemicals not requiring classification versus labelling for eye irritation or serious eye damage according to UN GHS. In an effort to promote its global use, the performance of the method was evaluated after long-distance shipment and compared to European shipment conditions. Results obtained by Cosmos Technical Center (Japan) after extended tissues transit were compared to results obtained in L'Oréal (France). Thirty-nine out of 40 blinded chemicals, representing different functional chemical classes, were consistently classified in both laboratories. The SkinEthic™ HCE EIT test method was also evaluated for its performance after extended storage of the tissues. The performance was in agreement with the values reported in OECD TG 492, with an overall accuracy of 87.1% (based on 119 chemicals), sensitivity of 95.5% and specificity of 73.5%. The reliability and relevance of SkinEthic™ HCE EIT test method after long-distance shipment and extended storage remain in agreement with regulatory validation criteria. Highlights • SkinEthic™ HCE Eye Irritation Testing (EIT) method has been adopted in OECD Test Guidelines 492. • Method performance remains comparable after long-distance shipment or extended storage of tissues. • Good within- and between laboratory reproducibility on 40 chemicals was achieved after tissues shipment from Europe to Asia. • After extended tissue storage, accuracy was 87.1% (119 chemicals) with a sensitivity of 95.5% and specificity of 73.5%. [ABSTRACT FROM AUTHOR]

Background: The treatment of orbital compartment syndrome has a rich history rooted in surgery and emergency medicine. It is a rare but acute and vision-threatening condition that most commonly occurs secondary to facial trauma or as a postoperative complication, and was first recognized in 1950. Surgical techniques and medical management were developed and refined soon afterwards to eventually become the modern-day treatment, lateral canthotomy, and inferior cantholysis.Objective: This article details the history of orbital compartment syndrome and the evolution of its treatment to the present day.Discussion: Given the time-sensitive nature and acuity of orbital compartment syndrome, lateral canthotomy was adopted by emergency physicians who could perform it more quickly at the bedside.Conclusions: Lateral canthotomy is a procedure adopted by emergency physicians from the surgical literature. The history of its adoption is a representative example of how emergency medicine evolves as a field. [ABSTRACT FROM AUTHOR]

Aim: Assess the feasibility, validity and precision of multimodal image fusion to capture oncology facial defects based on plaster casts.Methods: Ten casts of oncology facial defects were acquired. To create gold standard models, a 3D volumetric scan of each cast was obtained with a cone beam computed tomography (CBCT) scanner (NewTomVG). This was converted into surface data using open-source medical segmentation software and cropped to produce a CBCT mask using an open-source system for editing meshes. For the experimental model, the external facial features were captured using stereophotogrammetry (DI4D) and the defect was recorded with a custom optical structured light scanner. The two meshes were aligned, merged and resurfaced using MeshLab to produce a fused model. Analysis was performed in MeshLab on the best fit of the fused model to the CBCT mask. The unsigned mean distance was used to measure the absolute deviation of each model from the CBCT mask. To assess the precision of the technique, the process of producing the fused model was repeated to create five models each for the casts representing the best, middle and worst results.Results: Global mean deviation was 0.22 mm (standard deviation 0.05 mm). The precision of the method appeared to be acceptable although there was variability in the location of the error for the worst cast.Conclusion: This method for merging two independent scans to produce a fused model shows strong potential as an accurate and repeatable method of capturing facial defects. Further research is required to explore its clinical use. [ABSTRACT FROM AUTHOR]

Abstract This study developed an anatomical thin titanium mesh (ATTM) plate for Asian orbital floor fracture based on the medical image database. The computer aided stamping analysis was performed on four hole/slot patterns included the control type without hole design, circular hole pattern, slot pattern and hole/slot hybrid patterns within the ATTM plate with upper/lower dies of averaged orbital cavity reconstruction models. The curved-fan ATTM plate with 0.4 mm thickness was manufactured and pre-bent using a patient matched stamping process to verify its feasibility and the interfacial fitness between the plate and bone on the orbital floor fracture model. The stamping analysis found that the hole/slot hybrid patterns design resulted in the most favorable performance among all designs owing to the lowest maximum von-Mises stress/strain and spring-back value. The interfacial adaption results test showed that the average patient-matched stamping bending gap size was only 0.821 mm and the operative time was about 8 s. This study concluded that the curved-fan ATTM plate with hole/slot hybrid pattern design and patient-matched pre-bent technique can fit the ATTM plate/orbital cavity interface well, decrease unstable fracture segment mobility and improve the overall reduction efficiency. [ABSTRACT FROM AUTHOR]

To report the clinical experience and challenges faced for setting up the first interstitial ocular brachytherapy in Southeast Asia. A 11-year old girl diagnosed with rhabdomyosarcoma of the orbit became the first child patient who received chemotherapy and interstitial ocular brachytherapy in Singapore and within Southeast Asia. Interstitial Ocular brachytherapy holds an upper hand in delivering escalated conformal doses to the tumour that is not surgically resectable because of the close proximity to the orbit. It also provides an advantage over External Beam Radiation Therapy (EBRT) in reducing doses to orbit and neurological structures, and thereby potentially reducing risk of late toxicities of EBRT. Late toxicities of the EBRT reported cranio-facial deformities, visual adverse effects and neuroendocrine issues especially in very young children. Brachytherapy also minimises the risk of paediatric patients developing a second cancer due to the exposure of normal tissues to low dose radiation. Interstitial Ocular brachytherapy maybe an invasive alternative treatment option but with its potential benefits in lowered risk of late toxicities and shortened treatment duration. It serves as an attractive treatment option for young children with orbital tumors, and should be considered as an alternative to EBRT whenever feasible. The technical aspects of interstitial ocular brachytherapy can be challenging and demanding. The procedure carries the potential morbidities of both surgery and brachytherapy, including risks from general anaesthesia, infection, and patient immobilization over the duration of brachytherapy treatment. Hence, with careful case selection, optimum pre-planning and multi-disciplinary support from various institutions, a safe and effective treatment technique is developed. [ABSTRACT FROM AUTHOR]

Purpose To determine if conservatively treated blowout fractures of the orbit undergo spontaneous improvement based on radiologic findings. Design Prospective, noncomparative series. Participants Patients with conservatively treated orbital blowout fractures in a single tertiary institution from 2012 through 2016 with initial and follow-up computed tomography (CT) scans. Methods Comparison of initial and follow-up CT to assess for smoothening of bony contour, joining of bony edges, reduction in herniation of orbital contents, and new bone formation. Orbital and fracture volumes were calculated using a 3-dimensional reconstruction software program (3D Workstation; TeraRecon, Foster City, CA). Main Outcome Measures Change in bony contour, new bone formation, and decrease in orbital and fracture volumes. Results Our study comprised 41 patients and 44 orbits, with 38 unilateral and 3 bilateral cases. Most were men (65.9%; n = 27), and the mean age was 34.3±13.5 years. The mean time from injury to follow-up scan was 4.6 months (range, 1–15 months). All orbits showed changes in bony contour from initial to follow up CT, including smoothening of the orbital contour (88.6%), joining of bony edges (90.9%), and reduction in herniation of orbital contents (65.9%). Most of the orbits (n = 41; 93.2%) showed features of neobone formation. Of the 44 orbits, 91.4% showed a decrease in orbital volume, whereas 94.3% showed a decrease in fracture volume. The reduction in volume was statistically significant for both orbital (from 23.7±4.0 to 21.8±3.9 ml) as well as fracture (from 1.2±0.8 to 0.7±0.6 ml) volumes from initial to follow-up scans, respectively ( P < 0.001). Conclusions A large proportion of patients showed improvement in radiologic findings despite being treated conservatively. This highlights the spontaneous improvement that can occur in untreated blowout fractures not just clinically, but radiologically, in terms of soft tissue and bony findings. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to describe the positions of the lamina papyracea (LP) in patients who had nasal polypi, by computed tomography (CT) analysis.Methods: Paranasal CT scans of patients diagnosed to have nasal polypi were included in the study. CT images were acquired with multiplanar reformates to obtain delicate details in coronal planes for all subjects. Positions of the LP were registered then analyzed in relation to nasal polypi grading.Results: Forty seven subjects (94 nasal sides) were included in the current study. Grade I lamina detected in 50% or more of all cases. Patients who had larger polypi (polyp grade 3, 4) were associated with significantly more medial LP (grade II) than smaller polypi (polyp grade 0, 1, 2) (P=0.00386).Conclusion: The current study improves surgeons' awareness of LP position in different grades of nasal polypi and highlights that larger polypi are significantly associated with more medial LP than smaller polypi. This may be one of the causes of the higher incidence of complication in larger polypi and can help for safer surgery. [ABSTRACT FROM AUTHOR]

Although guidelines for facial approximations, including those for the eye, are in use in South Africa, limited data on African populations exist to confirm its validity. As precise placement of the eyes in facial approximations is of importance for facial recognition, this study tested established guidelines by measuring specific instrumental dimensions. Forty-nine cadavers from the Sefako Makgatho Health Sciences University and the University of Pretoria were dissected to determine the position of the canthi and the size and position of the eyeball in the orbit. Thirty cone beam computer tomography scans and 30 computer tomography scans from the Oral and Dental and Steve Biko Hospitals respectively were used to determine the size of the eyeball. Results from this study were compared to the published guidelines. The most prominent discrepancies included a more rectangular shape of the orbit, an oval shaped eyeball and a different position of the canthi. In African faces, the medial canthus was found to be located higher than the lateral canthus. The distance between the endocanthion and superior orbital margin was 17.7mm and the exocanthion and superior orbital margin 19.5mm. Inter-population differences may have an effect on facial approximations and its accuracy as is often demonstrated in practice. The findings of this study should be taken into consideration when designing population specific guidelines for reconstruction of the eye in South Africans of African ancestry. [ABSTRACT FROM AUTHOR]

Penetrating eye injuries are surgical emergencies with guarded visual prognosis. The purpose of the current study was to determine the force required to rupture the cornea with a penetrating object, and to study how this force is affected by the object geometry. Thirty-six human cadaveric eyes from donors of various ages were characterized for diameter, axial length, and pre-test intraocular pressure. In order to investigate the effects of specimen storage time on the tissue response, half of the specimens were tested within two weeks of donor expiration, and half of the specimens were stored at -4°C for 12-18 months. Indenters of three different diameters (1.0, 1.5, and 2.0mm) were lowered into the apex of the cornea until rupture. Resistance to displacement (stiffness), displacement at failure, and the force at failure were determined. Multi-variable regression analysis was used to determine associations of the input variables (indenter size, test speed, and tissue postmortem time) on the mechanics of the tissue response. Twenty-nine of the 36 specimens failed at the indenter location in the cornea, four failed at the limbus, and three failed in the sclera near sites of muscle attachment. The average force at failure caused by the 1.0mm, 1.5mm, and 2.0mm indenters increased from 30.5±5.5N to 40.5±8.3N to 58.2±14.5N, respectively (p<0.002). The force at failure was associated with the donor age (p<0.001), and globe diameter (p<0.041), but was not associated with pre-test intraocular pressure, tissue postmortem time, axial length, or speed of the indenter. This study has quantified the force-displacement and failure response of a large series of human cadaveric eyes subjected to penetrating indentation loads on the cornea. The results provide useful data for characterizing the relationship between corneal rupture and the geometry of a penetrating object. [ABSTRACT FROM AUTHOR]

Introduction: The recommended urgent surgical management of ocular motility restriction due to orbital muscle entrapment or impingement associated with orbital wall fracture needs to be elucidated.Aim: To evaluate the importance of the time from injury to surgery for the outcome in ocular motility and diplopia, the time lapse of ocular motility, diplopia and hypesthesia recovery.Material and Methods: Patients with entrapment or impingement of orbital contents due to orbital wall fracture were followed up prospectively over 1year regarding ocular motility, diplopia, hypesthesia and cosmetic deformity.Results: 21 patients (10 entrapments and 11 impingements) were included and treated surgically. The median time from injury to surgery was 36 (8-413)h for the entrapment group and 168 (48-326)h for the impingement group. The median time from study inclusion to surgery was 0 (0-1) days for the entrapment group and 1.0 (0.2-4.8) days for the impingement group. All the patients had ocular motility limitation and diplopia at the inclusion. Ocular motility improved gradually and was normal at final visit. Diplopia resolved gradually in all patients except in two with non-disturbing diplopia, at the final visit. Forced duction test was positive in 90% of the patients in the entrapment group and 70% in impingement group. At final visit, hypesthesia was found in none of the patients in the entrapment group but in 4 patients in the impingement group.Conclusions: In this, the first prospective long term follow up of orbital wall fractures with ocular motility restriction, we did not find any significant correlation between the time from injury to surgery and the outcomes in ocular motility and diplopia. An entrapment requires surgery as soon as possible; however, the surgical reduction is at least as important as surgical timing. Surgery should be delayed until it can be performed by an experienced surgeon. Ocular motility restriction causing diplopia due to impingement is not an ophthalmologic emergency and surgery is recommended if the diplopia and ocular motility has not improved over time. Clinical examination of ocular motility and not CT scan findings is crucial to determine whether a limitation of ocular motility exists or not. [ABSTRACT FROM AUTHOR]

Purpose To determine the necessity of rehabilitative surgical procedures for no implant anophthalmic sockets, and predictive factors of corrective operations after secondary orbital implantation. Material and methods Nineteen unilateral anophthalmic patients without orbital implant were included. The distance of eyebrow, upper eyelid margin, and lower eyelid margin from the horizontal medial canthal line (BM, UM, and LM, respectively) was measured using photographs. The anophthalmic orbit anatomy was compared with that of the healthy side using CT scans. Results Five (26.3%) patients showed satisfactory results with the secondary implantation alone. Fourteen (74%) patients needed additional surgeries for ptosis, shallow inferior fornix, enophthalmos, or lower eyelid malposition. Separated superior muscle complex and prominent intermuscular septum connecting the levator and the lateral rectus muscles were noticeable in CT scans. Predictive factors for ptosis surgery included longer BM ( p = 0.04), shorter distance from the superior orbital wall to the upper margin of the prosthesis ( p < 0.01), and a longer height of the prosthesis ( p = 0.04). Conclusion Most patients needed multiple operations after secondary implantation for rehabilitation. Additional ptosis operation may be required for patients with a high brow on the anophthalmic side, a vertically long prosthesis, and an impinged prosthesis against the superior orbital wall. [ABSTRACT FROM AUTHOR]

Purpose Nowadays, in orbital wall reconstruction, maxillofacial surgeons have the possibility to treat patients in modern ways such as with individual implants. Nevertheless, conventional treatment including standard titanium mesh shaped during the surgical procedure is also widely used. The aim of this study was to compare the above methods of orbital wall reconstructions. Materials and methods In the first group (39 cases), patients were treated by means of computer-aided design/computer-aided manufacturing (CAD/CAM) milled individual implants made of ultra–high-molecular-weight polyethylene, dioxide zirconium and rapid prototyping titanium mesh pre-bent on an ABS model made by a three-dimensional (3D) printer. In the second group (54 cases), intraoperative bending of titanium mesh was implemented. Results Ophthalmologic outcomes were the same in both groups. In patients who had greater destruction of the orbit, surgical procedures were longer regardless of the material used for individual implants (p < 0.05). Time of surgery was shorter in patients in whom individual implants were used. Intraoperative bleeding was higher in patients who were treated using intraoperative bending titanium mesh (p < 0.01). Conclusion Application of CAD/CAM techniques do not give better ophthalmologic results in reference center but improve patient condition postoperatively. For this reason, CAD/CAM is a safer treatment method for patients. [ABSTRACT FROM AUTHOR]

Background: Conventional reconstructive methods fail to achieve satisfactory results in total eyelid defect cases. Vascularized composite tissue allotransplantation might provide both good appearance and function for these patients. We developed an orthotopic periorbital transplantation model in rats to facilitate further experimentation in this field.Methods: In anatomical studies, the vascular distribution to and innervation of the periorbital unit were identified and recorded. Then, according to the anatomical studies, eight orthotopic transplantations and two transplantations with pedicle ligation were performed. The posterior facial vein and the external carotid artery were selected as the graft pedicles, while the temporal and upper zygomatic facial nerves were used for graft innervation. All transplanted eyelids were assessed daily. Micro-CT scanning and hematoxylin and eosin staining of the grafts were performed 60 days after the operation.Results: In total, 90% of recipients tolerated the operation well. All grafts without pedicle ligation survived, and new hair growth was observed. The position of the eyelid was maintained, and eyelid function was partially restored. In the recipients with graft pedicle ligation, the grafts became necrotic and mummified within four to five days. Micro-CT of the surviving grafts showed a good blood supply, and histological staining revealed normal morphology.Conclusions: A periorbital subunit orthotopic transplantation model was established, which might facilitate future eyelid allotransplantation-related experimentation. [ABSTRACT FROM AUTHOR]

In the treatment of severe oculo-orbital traumas, intraocular malignancies or other life-threatening conditions it is sometimes necessary to surgically remove the patient's diseased eye. Following the removal of the eye, an orbital implant is inserted into the anophthalmic socket in order to provide satisfactory volume replacement and restore the aesthetic appearance of a normal eye. Over the last decades, the implant design and the criteria of materials selection evolved from simple non-porous polymeric sphere to devices with more complex shape and functionalities for ensuring better clinical outcomes in the long-term. Polymeric and ceramic porous implants have gained prominence since their highly interconnected porous architecture allows them to act as a passive framework for fibrovascular in-growth offering reduced complication rates and the possibility of pegging to enhance the motility of the artificial eye. However, there are still drawbacks to these materials. Some critical aspects of today's orbital implants include the risk of migration and extrusion, postoperative infections and low motility transmitted to the aesthetic ocular prosthesis. Hence, the development of novel biomaterials with enhanced functionalities (e.g. angiogenesis, antibacterial effect, in situ mouldability) which enable an improved outcome of eye replacement is more than ever desirable and represents one of the most challenging topics of research in the field of ocular implants. This review summarizes the evolution of orbital implants and provides an overview of the most recent advances in the field as well as some critical remarks for materials design, selection, characterization and translation to clinical applications. [ABSTRACT FROM AUTHOR]

We present the case report of a 49-year-old gentleman with a history of adenoid cystic carcinoma of the left nare status post curative bifrontal craniotomy, left lateral rhinotomy and medial maxillectomy, adjuvant radiotherapy, and orbital exenteration for optic neuropathy, complicated by medial wall dehiscence. His course was also complicated by severe radiation trismus, for which he was scheduled to undergo bilateral mandibular coronoidectomies. Given his limited mouth opening, the surgeon requested a nasal endotracheal tube. Because of concerns of traumatizing his nare, we utilized a flexible fiberoptic bronchoscope to perform asleep transorbital intubation. Airway management in patients with severe trismus may require ingenuity. [ABSTRACT FROM AUTHOR]

The assessment of nature and the extent of extraocular muscle injuries during initial visit in ocular emergencies is of paramount importance to avoid/minimize the subsequent need for strabismus surgery. Based on our experience in managing acute globe and orbital injuries and cases of strabismus, we propose the probable mechanism involved in the occurrence of extraocular muscle flap tear and a complete rupture of the muscle. During high-velocity injuries when the forces are equally transmitted along the orbital bony framework and the globe, then due to differential shearing forces created between the global and the orbital fibres leads to a flap tear. In the second scenario, if the forces are only directed along the bony framework, then the globe continues to be in continuous motion leading to increased tension between the muscles and the globe. Thus the weaker portions between these two structures are at risk of complete separation, that is along the insertion of muscle onto the globe or the musculotendinous portion. [ABSTRACT FROM AUTHOR]

Purpose: Many diseases of traumatic, infectious, endocrinologic and neoplastic origin can lead to orbital involvement and related morphological changes. In the present study, we aimed to determine the age-based normal orbital measurements using magnetic resonance imaging (MRI) in pediatric patients.Methods: Our retrospective study included 186 patients with normal orbital MRI findings. The patients were divided into the following five groups based on their age. Group 1: 1-24 months; Group 2: 25-60 months; Group 3: 61-120 months; Group 4: 121-168 months; and Group 5: 169-216 months. Globe position relative to interzygomatic line (IZL) and orbital rim, optic nerve-sheath complex, extraocular muscle diameters, were measured.Results: The differences among the age groups for the distances between cornea and sclera in relation to IZL, for the distances between cornea and sclera relative to orbital rim, and for the extraocular muscle diameters were statistically significant. In terms of the extraocular muscle diameter, it was found that the thinnest muscle of all groups was the lateral rectus muscle while the thickest was the medial rectus muscle.Conclusion: In pediatric patients who were divided into five groups based on their age, the positions of bulbus oculi relative to IZL or orbital rim and the normal diameter ranges of extraocular muscles and of the optic nerve-sheath complex in orbital MRI were determined. We are of the opinion that the presence of such a scale could be a guide in the evaluation of orbital MRI in pediatric patients. [ABSTRACT FROM AUTHOR]