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Purpose: Hydrogel-based vitreous substitutes have the potential to overcome the limitations of current clinically used endotamponades. With the goal of entering clinical trials, the present study aimed to (I) transfer the material synthesis of hyaluronic acid–based hydrogels into a routine, pharmaceutical-appropriate production and (II) evaluate the properties of the vitreous substitutes in terms of the current regulations for medical devices (MDR/ISO standards). Methods: The multistep manufacturing process of the vitreous substitutes, including the modification of hyaluronic acid with glycidyl methacrylate, photocopolymerization with N-vinylpyrrolidone, and successive hydrogel purification, was developed under laboratory conditions, characterized using 1H-NMR, FT-IR and UV/Vis spectroscopies and HPLC, and transferred towards a pharmaceutical production environment considering GMP standards. The optical and viscoelastic characteristics of the hyaluronic acid–based hydrogels were compared with those of extracted human vitreous and silicone oil. The effect of the hydrogels on the metabolic activity, proliferation and apoptosis of fibroblast (MRC-5, BJ, L929), retinal pigment epithelial (ARPE-19, hiPSC-derived RPE) and photoreceptor cells (661W) was studied as well as their mucosal tolerance via a HET-CAM assay. Results: Hyaluronic acid–based hydrogels having a suitable purity, sterility, high transparency (>90%), appropriate refractive index (1.3365) and viscoelasticity (G′ > G″) were prepared in a standardized manner under controlled process conditions. The metabolic activity, proliferation and apoptosis of various cell types as well as egg choroid were unaffected by the hyaluronic acid–based vitreous substitutes, demonstrating their biocompatibility. Conclusions: The present study demonstrates the successful transferability of the crucial synthesis steps of hyaluronic acid–based hydrogels into a routine, GMP-compliant production process while achieving the optical and viscoelastic properties, biocompatibility and purity required for their clinical use as vitreous substitutes.

OBJECTIVES: To investigate the safety and effectiveness of pre-emptive vitrectomy in eyes with severe non-fibrotic proliferative diabetic retinopathy.METHODS: A multi-centre, retrospective, observational study. Pre-emptive vitrectomy was performed in non-fibrotic diabetic eyes with a visual acuity (VA) of 20/50 or better, where there was extensive persistent neovascularisation despite prior panretinal photocoagulation, and where the fellow eye had established sight loss despite vitrectomy for tractional complications. The primary outcome measure was the VA at last visit.RESULTS: Twenty patients were included. The mean age was 39 ± 14 years. Fifteen patients were Type 1 diabetic. The median baseline VA was 20/30 and remained stable at 20/28 at last visit (median follow-up period: 24 months). Eight eyes (40.0%) developed post-operative vitreous cavity haemorrhage; 4 of which required a vitreous cavity washout procedure. There were no post-operative retinal detachments. The index eye remained the significantly better eye at all time points bar one month post-surgery. Regression of retinopathy grading was observed in all eyes.CONCLUSION: In this pilot study, we found no sight loss with pre-emptive diabetic vitrectomy. Better eye status was maintained in this high-risk group. Further study with larger number of patients and longer-term follow-up is indicated.

Purpose We aimed to establish a rabbit model with retinal atrophy induced by an iatrogenic retinal pigment epithelium (RPE) removal, for future testing of the efficacy and safety of cell therapy strategies. Methods A localized detachment of the retina from the RPE/choroid layer was created in 18 pigmented rabbits. The RPE was removed by scraping with a custom-made extendable loop instrument. The resulting RPE wound was observed over a time course of 12 weeks with optical coherence tomography and angiography. After 4 days (group 1) and 12 weeks (group 2), histology was done and staining with hematoxylin and eosin, as well as immunofluorescence performed to further investigate the effects of debridement on the RPE and the overlying retina. Results Already after 4 days, we observed a closure of the RPE wound by proliferating RPE and microglia/macrophage cells forming a multilayered clump. This pattern continued over the observation time course of 12 weeks, whereby the inner and outer nuclear layer of the retina became atrophic. No neovascularization was observed in the angiograms or histology. The observed changes were limited to the site of the former RPE wound. Conclusions Localized surgical RPE removal induced an adjacent progressive retinal atrophy. Altering the natural course of this model may serve as a basis to test RPE cell therapeutics.

ZusammenfassungWeitaus seltener und daher weniger bekannt als die altersbedingte Katarakt ist die sekundär erworbene Katarakt, die eine diagnostische und chirurgische Herausforderung darstellen kann. Dieser Beitrag gibt einen Überblick über die häufigsten Subtypen vor allem bei Erwachsenen und beleuchtet die chirurgischen Besonderheiten einschließlich perioperativer Charakteristika.

Purpose To determine a statistically optimal limit of adhesion size in vitreomacular traction (VMT) syndrome for ocriplasmin treatment. Methods In this retrospective, consecutive, interventional study, we included 106 patients treated with ocriplasmin injection due to VMT between July 2013 and January 2018. A univariate and multivariate risk analysis was performed with grouped factors and continuous factors. We used a receiver operating characteristic curve to measure the prognostic relevance of each continuous factor for therapy success and determined the statistically optimal cutoff value at which specificity and sensitivity are simultaneously maximized. Results Among the grouped factors, only a phakic lens status showed a highly significant positive influence on the resolution of the VMT. For the continuous factors, only the adhesion diameter before injection was a good predictor of anatomical success. The statistically optimal threshold value for the adhesion size was calculated to be 480 µm. Eyes below this limit had a 6.84-fold better chance of VMT resolution compared to eyes with a larger adhesion diameter. Conclusion The threshold value of the VMT diameter for ocriplasmin therapy could be statistically defined as 480 µm and may thus be a new quantitative biomarker to predict treatment success.

A 66-year-old patient underwent surgery for congenital cataract in both eyes in her first year of life without implantation of an intraocular lens (IOL). In 1994, at the age of 39 years, both eyes received secondary Kelman multiflex-style angle-fixated anterior chamber IOLs (AC IOLs). The surgeries were followed by retinal detachments in both eyes, in the left eye in the same year and in the right eye 4 years later, which were successfully repaired. The patient presented with a decompensated cornea with epithelial and stromal edema in the left eye. The AC IOL axis was oriented from 5- to 8-o'clock position with the haptic contacting the cornea. The distal portion of the inferior-nasal haptic was deeply buried and entrapped in a broad iridocorneal synechia extending between 6- and 8-o'clock positions. The synechia also caused adjacent pupillary distortion and pigment leaf eversion (Figure 1JOURNAL/jcrs/04.03/02158034-202205000-00021/figure1/v/2022-04-22T173532Z/r/image-tiff). The AC IOL in the right eye was well positioned, and the cornea was clear with an endothelial cell count (ECC) of 2160 cells/mm2 and central corneal thickness (CCT) of 650 μm. No ECC was obtainable in the left eye, and CCT was 775 μm (Figure 2JOURNAL/jcrs/04.03/02158034-202205000-00021/figure2/v/2022-04-22T173532Z/r/image-tiff). Visual acuity was 0.8 corrected in the right eye and hand motion in the left eye. Both eyes were normotonic. On optical coherence tomography (OCT) imaging, a broad iridocorneal synechia was visible with a canal corresponding to the deeply buried haptic end of the AC IOL (Figure 3JOURNAL/jcrs/04.03/02158034-202205000-00021/figure3/v/2022-04-22T173532Z/r/image-tiff). Abundant condensed cortical material (Soemmerring's ring) was found behind the iris and above the ciliary body. What would be your surgical options to rehabilitate the patient's left eye considering corneal decompensation caused by haptic contact of an angle-fixated AC IOL and capture of 1 haptic within an iridocorneal synechia extending along 2 clock hours?

Purpose To present a modified surgery technique of suture probe canaloplasty with a specially prepared monofilament 4.0 polypropylene suture combined with suprachoroidal drainage (ScD) and collagen sheet implantation for non-penetrating glaucoma surgery.MethodsProspective study with a twelve months follow-up.In order to improve suture probe canaloplasty with a more stable und smoother probing device, a standard 4/0 polypropylene suture (Prolene™ by Ethicon) (thickness: ca. 250µm) is cut and shaped with an ophthalmic knife (MANI® Crescent Knife, Mani Inc 8-3 Kiyohara Industrial Park, Utsunomiya, Tochigi 321-3231, Japan) to create a blunt end without sharp or compressed edges. Schlemm´s canal is prepared with the standard technique of canaloplasty with suprachoroidal drainage. Then instead of using the canaloplasty microcatheter or the previously published 6.0 double-helix suture - Schlemm’s canal is probed with the blunt ending 4/0 prolene suture. In case of successful 360° probing a doubled 10/0 polypropylene tension suture is thread through the 4/0 suture, which is afterwards pulled backwards and tied at its ends. Schlemm’s canal is hereby tensioned with these 10/0 sutures. A special collagen sheet (Ologen®) is placed in suprachoroidal space, and the scleral flap is firmly sewed.Results115 eyes were included in this prospective study. In 113 cases the Schlemm´s canal could completely be probed with the suture and canaloplasty with ScD and collagen sheet implantation succeeded. In two cases the intervention was transformed to 360° suture trabeculotomy due to an intraoperative cheese-wiring. Twelve months after successful new suture probe canaloplasty with ScD and Collagen Implantation the IOP had decreased by 37.1% (from 21.6±6.0 mmHg with 3.3 different IOP lowering eye drops to 13.5±3.5mmHg with 1.0 eye drops). 16 Patients did not achieve sufficient IOP levels and underwent 360° suture trabeculotomy during the follow-up. One patient had to be treated with further glaucoma surgery to achieve a sufficient IOP level.Complications were hyphema, postoperative IOP elevation and transient hypotony. No serious or sight-threatening complications occurred.ConclusionNew suture probe canaloplasty with ScD and collagen sheet implantation yields the opportunity to conduct a cost-effective canaloplasty easier and less complicated than with the previously described method with the twisted 6/0 suture. The safety profile and IOP lowering effect is comparable. In cases where complete probing fails, there is still the opportunity to switch to suture trabeculotomy over the majorly probed part of Schlemm´s canal. The pressure lowering effect of the deep sclerectomy with ScD and suprachoroidal collagen sheet implant seems to have an additional impact on the sufficient pressure lowering procedure.

For decades, trabeculectomy (TE) was considered the gold standard for surgical treatment of open-angle glaucoma owing to its powerful intraocular pressure (IOP)-lowering potency. However, owing to the invasive nature and high-risk profile of TE, this standard is changing, and minimally invasive procedures are becoming more preferable. In particular, canaloplasty (CP) has been established as a much gentler alternative in everyday life and is under development as a full-fledged replacement. This technique involves probing Schlemm’s canal with a microcatheter and inserting a pouch suture that places the trabecular meshwork under permanent tension. It aims to restore the natural outflow pathways of the aqueous humor and is independent of external wound healing. This physiological approach results in a significantly lower complication rate and allows considerably simplified perioperative management. There is now extensive evidence that canaloplasty achieves sufficient pressure reduction as well as a significant reduction in postoperative glaucoma medications. Unlike MIGS procedures, the indication is not only mild to moderate glaucoma; today, even advanced glaucoma benefits from the very low hypotony rate, which largely avoids a wipeout phenomenon. However, approximately half of patients are not completely medication-free after canaloplasty. As a consequence, a number of canaloplasty modifications have been developed with the goal of further enhancing the IOP-lowering effect while avoiding the risk of serious complications. By combining canaloplasty with the newly developed suprachoroidal drainage procedure, the individual improvements in trabecular facility and uveoscleral outflow facility appear to have an additive effect. Thus, for the first time, an IOP-lowering effect comparable to a successful trabeculectomy can be achieved. Other implant modifications also enhance the potential of canaloplasty or offer additional benefits such as the possibility of telemetric IOP self-measurement by the patient. This article reviews the modifications of canaloplasty, which has the potential to become a new gold standard in glaucoma surgery via stepwise refinement.

Postoperative endophthalmitis is one of the most feared complications for ophthalmologists, and the number of infections after intraocular procedures have been increasing. Nonetheless, a prompt intervention can result in the recovery of vision. In the past, endophthalmitis after cataract surgery was accountable for the majority of cases but is becoming less frequent due to the progress of surgical techniques and demographic developments with a steadily increasing number of intravitreal injections. In this article, the different forms of postoperative endophthalmitis are assessed in terms of pathophysiology and their specific characteristics depending on their etiology.

Purpose Effectiveness of ocriplasmin for vitreomacular traction (VMT) varies depending on the presence of common ocular conditions and patient selection criteria. We carried out a systematic literature review and meta‐analysis of ocriplasmin studies conducted in real‐world settings (RWS) and compared outcomes with those from randomized controlled trials (RCTs). Methods We included prospective and retrospective studies from RWS documenting effectiveness of ocriplasmin in patients with VMT with or without MH, and RCTs of ocriplasmin versus control. Key end‐points were vitreomacular adhesion resolution (VMAR), nonsurgical MH closure, need for vitrectomy and safety. We conducted meta‐regression on pooled results to evaluate effects of baseline covariates and study design on outcomes. Results Thirty RWS (2402 patients) and 5 RCTs (737 patients) were included epiretinal membrane (ERM) and broad VMA were more prevalent in RCTs. Primary VMAR, vitrectomy and MH closure rates were comparable between RWS and RCTs. Rates of nsVMAR were significantly higher in RWS than RCTs (odds ratio 1.66; 95% confidence interval [CI]: 1.18–2.34). nsVMAR rates were inversely associated with ERM prevalence (odds ratio 0.20; 95% CI: 0.08–0.51). Compared with the recent OASIS trial, RWS reported a higher incidence of new/worsening subretinal fluid cases and less photophobia, photopsia, vitreous floaters, electroretinogram abnormalities and MH progression. Conclusions Ocriplasmin was significantly more effective in achieving nsVMAR in RWS than in RCTs. Lower ERM prevalence in RWS was the single significant explanatory variable for this difference. Conclusions on ocriplasmin safety in RWS are limited due to inconsistent reporting.

Trabeculectomy still achieves the strongest intraocular pressure (IOP) reduction of all glaucoma surgical techniques, but with the drawback of a significant risk profile. Against this background, canaloplasty has established itself as a much gentler alternative which achieves sufficient IOP reduction and enables a significant reduction in postoperative glaucoma medication. However, approximately half of patients are not completely medication free. In response, a number of modifications have been developed with the goal of further enhancing the IOP-lowering effect of canaloplasty, but without the risk of serious complications. By combining canaloplasty with the newly developed suprachoroidal drainage, a uveoscleral drainage is created in addition to the trabecular outflow improvement, which seems to have an additive effect. Thus, for the first time, an IOP-lowering effect comparable to successful trabeculectomy can be achieved. Numerous other modifications with implants also enhance the potential of canaloplasty or offer other additional benefits such as the possibility of telemetric IOP self-measurement by the patient. The additional creation of a subconjunctival drainage with or without use of cytostatic drugs also seems promising. Ab interno procedures, on the other hand, have limited pressure-lowering potential but may provide some additional benefit in mild glaucoma and in the setting of cataract surgery.Die Trabekulektomie erzielt zwar weiterhin die stärkste Drucksenkung aller glaukomchirurgischen Maßnahmen, allerdings zum Preis eines nicht unerheblichen Risikoprofils. Vor diesem Hintergrund hat sich die Kanaloplastik als deutlich schonendere Alternative etabliert und erzielt eine ausreichende Drucksenkung sowie ermöglicht eine signifikante Reduktion der postoperativen Glaukommedikamente. Allerdings ist etwa die Hälfte der Patienten nicht vollständig tropfenfrei. Als Antwort darauf wurden eine Reihe von Modifikationen entwickelt, die zum Ziel haben, den drucksenkenden Effekt noch weiter zu verstärken, jedoch ohne das Risiko für schwerwiegende Komplikationen. Durch die Kombination einer Kanaloplastik mit der neu entwickelten suprachoroidalen Drainage wird neben der Verbesserung der trabekulären Abflussmöglichkeiten zusätzlich ein uveoskleraler Abfluss geschaffen, der additiv zu wirken scheint. Damit lässt sich erstmals ein drucksenkender Effekt erreichen, der mit einer erfolgreichen Trabekulektomie vergleichbar ist. Zahlreiche weitere Modifikationen mit Implantaten verstärken ebenfalls das Potenzial der Kanaloplastik oder bieten weitere Zusatznutzen wie die Möglichkeit einer telemetrischen Selbstmessung des Augeninnendrucks (IOD) durch den Patienten. Auch die zusätzliche Schaffung eines subkonjunktivalen Abflusses mit oder ohne Einsatz von Zytostatika scheint vielversprechend zu sein. Ab-interno-Verfahren haben dagegen nur ein begrenztes drucksenkendes Potenzial, können aber bei leichtgradigen Glaukomen und im Rahmen der Kataraktchirurgie einen gewissen Zusatznutzen liefern.

Measuring and controlling intraocular pressure (IOP) provide the foundation for glaucoma treatment. Self-tonometry has been proposed as an alternative to measure IOP throughout the entire day better. The novel EYEMATE-SC sensor (Implandata) is implanted in the suprachoroidal space to enable contactless continual IOP monitoring. The aim of the present study was to investigate the 1-year safety, performance, and accuracy of the EYEMATE-SC in patients with primary open-angle glaucoma undergoing simultaneous nonpenetrating glaucoma surgery (NPGS).Prospective, multicenter, open-label, single-arm, interventional clinical trial.Twenty-four eyes of 24 patients with primary open-angle glaucoma who were due to undergo NPGS (canaloplasty or deep sclerectomy).An EYEMATE-SC sensor was implanted during NPGS. Goldmann applanation tonometry (GAT) measurements were compared with the sensors' IOP measurements at all postoperative visits through 12 months.Device position and adverse events.Fifteen eyes underwent canaloplasty, and 9 underwent deep sclerectomy. Successful implantation of the sensor was achieved in all eyes with no reported intraoperative difficulties. Through the 12-month follow-up, no device migration, dislocation, or serious device-related complications were recorded. A total of 536 EYEMATE-SC measurements were pairwise included in the IOP agreement analysis. The overall mean difference between GAT and EYEMATE-SC measurements was 0.8 mmHg (95% confidence interval [CI] of the limits of agreement [LoA], -5.1 to 6.7 mmHg). The agreement gradually improved, and from 3 months after surgery until the end of the follow-up, the mean difference was -0.2 mmHg (95% CI of LoA, -4.6 to 4.2 mmHg) over a total of 264 EYEMATE-SC measurements, and 100% of measurements were within ±5 mmHg of GAT.The EYEMATE-SC sensor was safe and well tolerated through 12 months. Moreover, it allowed accurate, continuous IOP monitoring.

Senile or age-related cataract is well known to ophthalmologists and also to colleagues in other medical specialties. Age-related cataract represents the most common cause of blindness worldwide but can be treated very successfully by a standard outpatient surgery. Far less common and therefore less known is the acquired cataract that can present a diagnostic and surgical challenge. The following article provides the reader with an overview of secondary acquired cataracts. The most common subtypes are mentioned first and then discussed in more detail so that the reader should have a structured knowledge after reading this article. This article focuses on acquired cataracts primarily in adults and highlights the surgical features including perioperative characteristics.

To evaluate the long-term efficacy and safety of the modified canaloplasty technique with additional suprachoroidal drainage in patients with pseudoexfoliation glaucoma. This retrospective clinical...

Persisting macular holes (PMH) after surgical release of any epiretinal traction of the vitreous and adjacent membrane may rely on secondary firm adhesions between the retracted retina and adjacent retinal pigment epithelium. Secondary application of subretinal (SR)-fluid may release these adhesions followed by an anatomical closure. Twelve surgeons applied in a consecutive case series SR-fluid in 41 eyes with PMH and reported retrospectively their initial surgical, anatomical and functional experience with this approach. The mean duration of the MH prior to SR-fluid application was 17 months (6–96 months). The mean age of the patients at the time of surgery was 72 years (54–88). The mean preoperative aperture diameter of the opening was 1212 μm (239–4344 μm), base diameter 649 μm (SD 320 μm). The mean preoperative BCVA prior to surgery was 0.1 (0.01–0.3). All patients (41/41) complained about reduced BCVA and a significant central scotoma (negative scotoma) in their central field of vision. The secondary closure rate for our PMH was 85.36% (35 out of 41 eyes) at 6 weeks after surgery. The postoperative BCVA improved to 0.22 (0.02–0.5). The application of SR-fluid was not associated with major intraoperative adverse effects. Remaining SR-adhesions may inhibit PMH closure. Their release by application of SR-fluid will lead to a fast and immediate anatomical closure in many cases without serious adverse events.

Purpose The aim of this study was to determine whether the choice of scleral indentation technique during primary rhegmatogenous retinal detachment surgery has an influence on the risk of re-detachment. Methods We included retrospectively 154 eyes with a primary rhegmatogenous retinal detachment treated in the Eye Clinic Sulzbach/Saar Germany, who were operated on by two experienced surgeons using the same basic surgical setup. Surgeon A performed an external 360° indentation, shaved the vitreous base using the light pipe cap, and used the operating microscope (opm) for direct visualization. Surgeon B performed an external 360° indentation, shaved the vitreous base using a simple indentor, and used an endoillumination (light pipe) with the opm and a handheld widefield lens for direct visualization. Results Comparing both indentation procedures, 15.66% (13/83) of patients operated on by surgeon A and 9.86% (7/71) of patients operated on by surgeon B had a retinal re-detachment within a follow-up period of 6 months (adj. p = 0.64, two-proportion Z-test). Conclusion The rate of retinal re-detachment could be influenced by the indentation technique at the end of surgery favoring external indentation and internal visualization with an endoilluminator (chandelier light). We attribute this to the better visualization of the vitreous base facilitated by endoillumination. However, many variables play a role in the development of retinal re-detachment, requiring further studies with a larger number of patients.

Vitreous substitutes are traditionally used to stabilize the retina after vitrectomy. In recent years, various approaches have been developed for using the vitreous substitute not only as a tamponade but also as a drug release system to tackle ocular diseases. This review provides an overview of the requirements for vitreous substitutes and discusses the current clinically applied as well as novel polymer-based vitreous substitutes as drug delivery systems, including their release mechanisms, efficiencies, challenges, and future perspectives.