Bleb reconstruction using donor scleral patch graft for late bleb leak and hypotony

The Evolving Surgical Paradigm of Scleral Allograft Bio-Tissue Use in Ophthalmic Surgery: Techniques and Clinical Indications for Ab-Externo and Ab-Interno Scleral Reinforcement

To review the latest surgical advances and evolving clinical use of scleral bio-tissue for reinforcement in the eye and review the published literature on novel surgical applications of scleral allograft bio-tissue. Conventional surgical procedures for scleral reinforcement using homologous scleral allograft have been traditionally ab-externo interventions comprising of anterior or posterior reinforcement of the sclera for clinical indications such as trauma, scleromalacia, glaucoma drainage device coverage, scleral perforation, buckle repair as well as posterior reinforcement for pathologic myopia and staphyloma. There have been a few novel ab-interno uses of scleral bio-tissue for reinforcement in both retina and glaucoma. Over the last decade, there has been an increase in peer-reviewed publications on scleral reinforcement, reflecting more interest in its clinical applications. With favorable biological and biomechanical properties, scleral allograft may be an ideal substrate for an array of new applications and surgical uses.

Scleral Grafts in Ophthalmic Surgery. A Review

AIM

To summarize the history and current trends in the use of scleral grafts in ophthalmology.

MATERIALS AND METHODS

We conducted a review of the literature through the MEDLINE and Cochrane Library databases. The search terms were "sclera", "graft", and "surgery". The search resulted in 1596 articles, of which we evaluated 192 as relevant. The relevant articles were sorted chronologically and according to the method of using scleral grafts, which enabled the development of a review article.

RESULTS

The sclera has been routinely used in ophthalmology since the 1950s in many different indications. Some of these indications have become practically obsolete over time (for example, use in the surgical management of retinal detachment), but a large number still find application today (especially use in glaucoma or oculoplastic surgery, or as a patch for a defect in the sclera or cornea).

CONCLUSION

Even though allogeneic sclera is currently used less frequently in ophthalmology compared to other tissue banking products and the range of its indications has partially narrowed, it remains a useful material due to its availability and properties.

Long-term outcomes of blebs repaired with scleral patch graft and conjunctival advancement in late-onset leak post-trabeculectomy

Purpose:

To report long-term outcomes in eyes that developed late-onset bleb leak post trabeculectomy, with or without hypotony and/or maculopathy, due to a scleral melt/fistula and who required a scleral patch graft and conjunctival advancement for repair.

Methods:

Retrospective, non-comparative, interventional case series over a decade (2010–2019), presenting with late bleb leak post-filtration-surgery. All cases required a scleral patch graft and conjunctival advancement for management via a standard technique, performed by an experienced glaucoma surgeon.

Results:

A total of 18 eyes were included. Mean age was 51.5 ± 10.2 years (95% CI [46.4–56.7]) and were followed up after repair for 52.4 ± 26.9 months, 95%CI [39.1–65.8]. 66.7% eyes (n = 12) had IOP ≦6 mmHg and also had hypotony maculopathy. None of the eyes presented with blebitis. 44.5% (n = 8) eyes underwent phacoemulsification as significant cataract was present. LogMAR best-corrected visual acuity (BCVA) was 0.8 ± 0.7 (95% CI [0.4–1.1]) prior to intervention and improved to 0.4 ± 0.6 (95% CI[0.1–0.6], P = 0.004). 22.3% (n = 4) eyes had persistent choroidal folds but BCVA was improved. Mean pre-intervention intraocular pressure (IOP) was 6.3 ± 3.8 mmHg (95% CI 4.4–8.2]) which increased to 12.1 ± 2.9 mmHg (95%CI[10.6–13.5], (P < 0.001). 27.8% (n = 5) eyes needed laser suture lysis post repair to control IOP; two needed further surgical intervention. Number of anti-glaucoma medications at last follow-up was 0.4 ± 0.9 (95% CI [−0.1–0.8], P = 0.09). No serious complications were encountered.

Conclusion:

Scleral patch graft and conjunctival advancement is a useful technique for repair of a scleral fistula post-filtering surgery, and this is recommended not only for the restoration of anatomy for prevention of infection and control of IOP, but also for visual rehabilitation.

The usability of lamellar scleral autograft in ocular perforation treatment

IMPORTANCE

Open globe injury is a frequent and preventable healthcare problem with an annual incidence of 3.5/100,000 worldwide. Management and treatment methods aim to ensure globe integrity. Unfortunately, it is not possible to achieve globe integrity in some of the cases, and these can result in poor visual outcomes.

PURPOSE

To evaluate the usability of lamellar scleral graft in the repair of ocular perforations.

METHODS

This was a retrospective review of 11 patients who underwent lamellar scleral graft surgery for ocular perforation between June 2015 and June 2020. Due to the failure of the repairs when other techniques were used, the perforation zones were sealed with lamellar scleral autografts. The primary measures of the outcomes were globe integrity, postoperative best corrected visual acuity, and intraocular pressure (IOP). Visual acuity was determined using the Snellen eye chart, and IOP was measured using the automated pneumatic tonometry during standard examination.

RESULTS

The participants enrolled in this study included 11 patients who underwent lamellar scleral patch graft between 2015 and 2020. The mean age of the patients was 58.81 ± 16.6 years (range, 16-77), and the mean follow-up period was 12.5 ± 3.8 months (range, 8-20). During the surgery, the perforation zone was treated and no leakage was observed. IOP significantly increased, and visual acuity improved in almost all eyes. The factors that made it necessary to use scleral grafts in patients were star-shaped wounds, delayed presentation, lost corneal / scleral tissue.

CONCLUSION

Lamellar scleral graft is a method that can be used in the treatment of defective ocular perforation with acceptable complications and provides adequate functional and structural stability. Scleral patch grafting can be considered as an alternative option for surgeons treating a variety of ocular conditions that cause tectonic imbalance or poor cosmesis.

The use of Ologen Collagen Matrix implants to treat ocular hypotony developing after trabeculectomy: A case series

PURPOSE

Late hypotony is an undesirable and challenging complication of glaucoma surgery. We describe our use of the Ologen Collagen Matrix to treat late hypotony developing after trabeculectomy.

STUDY DESIGN

A retrospective study performed at three eye surgery centers in Brazil.

PARTICIPANTS

Eighteen patients who underwent 19 eye surgeries.

INTERVENTION

Subconjunctival Ologen was implanted at the trabeculectomy sites to treat over-filtering or leaking blebs in patients experiencing late hypotony after trabeculectomy (obtained 6 months after glaucoma surgery). The primary outcome was the intraocular pressure (IOP); we gathered preoperative data records from 19 Ologen treated eyes and days 1, 7, 30, 60, and 180 postoperatively. The secondary outcomes included visual acuity and macular thickness measured via optical coherence tomography; we compared preoperative data to subsequent ones up to sixth-month-evolution.

RESULTS

Over the 6-month period, the IOP rose from 2.89 ± 1.59 mmHg preoperatively to 8.21 ± 3.46 mmHg (p = 0.0001). Visual acuity improved from 0.33 ± 0.29 to 0.21 ± 0.31 LogMar (p = 0.0013). Macular thickness fell from 325.62 ± 58.7 to 283.08 ± 47.35 µm (p = 0.0097). We encountered two complications: one related to suture dehiscence following an ocular trauma and one instance of transitory choroidal detachment.

CONCLUSION

Subconjunctival Ologen implants preserved bleb function and successfully treated post-trabeculectomy hypotony as revealed by data collected at the 6-month follow-up. Longer follow-up is necessary to confirm long-term efficacy and safety. There are no financial conflicts of interest to disclose.