Results of an Adaptive Surgical Approach for Managing Late Onset Hypotony After Trabeculectomy With Mitomycin C

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.

Outcome of Bleb Revision With Autologous Conjunctival Graft Alone or Combined With Donor Scleral Graft for Late-onset Bleb Leakage With Hypotony After Standard Trabeculectomy With Mitomycin C

PRCIS

Treatment of leakage with ocular hypotony after trabeculectomy with mitomycin C (MMC) can be safely achieved through conjunctival patch alone or combined with donor scleral graft in cases of melted underlying sclera.

PURPOSE

To report outcomes of 2 surgical approaches for treating ocular hypotony in eyes with blebs with late-onset leakage after standard trabeculectomy with MMC.

METHODS

Thirty consecutive cases with bleb leakage and hypotony underwent bleb revision surgery between 2009 and 2014 by the same surgeon (J.W.) at the Department of Ophthalmology of the Mainz University Medical Center, Germany. In 18 patients, an autologous conjunctival patch graft was applied. In 12 patients, the underlying sclera was found melted and an additional scleral donor graft was sutured in place. The authors analyzed intraocular pressure, visual acuity, and optical coherence tomography of the macula preoperatively at 1 day, 1 week, 4 weeks, and 6 months after surgery.

RESULTS

The mean IOP was 6.2±3.5 mm Hg preoperatively and 21.7±16.4 mm Hg at 1 day, 13.7±6.7 at 1 week, 13.1±5.1 mm Hg at 4 weeks, and 12.1±4.7 mm Hg at 6 months after surgery. Visual acuity (logMar) increased from 0.57±0.49 preoperatively to 0.49±0.40 at 6 months. Optical coherence tomography showed flattening of macular folds that were present before treatment. No serious adverse event was reported.

CONCLUSIONS

This revision technique with conjunctival patch and/or additional donor scleral graft is an effective and safe method for treating late bleb leakage and hypotony maculopathy after trabeculectomy with MMC.

Outcome, influence factor and development of CLS measurement in continuous IOP monitoring: A narrative review

A large fluctuation in intraocular pressure (IOP) and a high peak IOP remain the risk factors for progressive visual field loss in patients with glaucoma, which is a leading cause of irreversible blindness. However, IOP measurements during working time cannot provide sufficient information on IOP to guide clinicians in setting IOP target values. Contact lenses are extensively used in ophthalmology to correct the refractive error, and recently, they are serving as platforms for detection and drug delivery. Contact lens sensor (CLS) is a feasible and promising approach to continuously monitor IOP, with superior tolerance, non-invasiveness, and without sleep disturbance. The present work reviewed the associations between progressive course and Triggerfish® CLS outputs as well as the relationship between treatments and Triggerfish® CLS outputs. Moreover, it further summarized state-of-the-art CLS devices of the past decade.

Conjunctival flap advancement with or without scleral graft for hypotony maculopathy after trabeculectomy

AIM

To investigate the outcomes of adaptive conjunctival flap advancement surgical techniques with or without scleral graft for patients undergoing revision surgery after trabeculectomy.

METHODS

This retrospective study included 28 eyes of 28 subjects from December 2015 to April 2018. A group of 15 eyes underwent conjunctival advancement only while the other 13 eyes did conjunctival advancement with partial thickness scleral graft. In both study groups, we considered the intraocular pressure (IOP) as our primary outcome and visual acuity (VA) as our secondary outcome. Both were assessed pre- and post-operatively till the last follow-up possible point. Additionally, we classified the patients according to complete and qualified success criteria.

RESULTS

The mean age of the conjunctival advancement group was 36.87±19.25y, while it was 44.08±18.04 in the other group. In both study groups, the mean IOP significantly increased after revision surgery at 1, 2, 3mo and the last follow-up visit when compared to prior the surgery (P<0.001). Moreover, VA was significantly improved (P=0.03) in the final follow-up for both surgical techniques. When we compared the change from baseline in both groups, there was no significant difference between IOP improvement in 1mo (P=0.263), while the difference was significant in 2mo (P=0.03), 3mo (P=0.02) and in the final follow-up visit postoperatively. However, this difference was not significant regarding VA (P=0.5).

CONCLUSION

The both adaptive techniques of conjunctival advancement and conjunctival advancement with scleral graft are effective for treating patients with late-onset hypotony. Yet, more prospective studies are needed to assert upon these results.

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

PURPOSE

Bleb dysfunction may occur as a late complication following glaucoma filtration surgery. Over-filtering, thinning and cystic blebs can lead to hypotony, leak and corneal dellen. We report our surgical management and outcomes of this specific entity using donor scleral patch grafts.

METHODS

This is a 10-year non-comparative, retrospective interventional case series. Bleb reconstruction involved excision of encysted conjunctiva and sclera to identify the original fistula. A functioning donor scleral patch graft was sited over this with fixed and releasable sutures and the conjunctiva advanced. Intraocular pressure, visual acuity and post-operative issues were assessed.

RESULTS

A total of 18 eyes of 17 patients with mean age 65 years (standard deviation 13.5) were included. Trabeculectomy was the primary procedure in 72% (n = 13) and deep sclerectomy in 28% (n = 5). Bleb leak accounted for 61% (n = 11), hypotony 33% (n = 6) and corneal dellen 6% (n = 1). Mean pre-operative intraocular pressure was 7 mm Hg (standard deviation 4.6) which increased to 18.5 mm Hg (standard deviation 12) at day 1 (p < 0.001), 11.8 mm Hg (standard deviation 4.6) at 3 months (p < 0.05), 12.1 mm Hg (standard deviation 4.2) at 1 year (p < 0.01) which was maintained at 12.1 mm Hg (standard deviation 5.3) at last follow-up (p < 0.001). Post-operative interventions included bleb needling, re-suturing, suture removal, further glaucoma management, bleb leak and cataract surgery. Visual acuity also improved post-operatively and was maintained.

CONCLUSION

Reconstruction of the filtering bleb architecture with donor sclera results in improved intraocular pressure while maintaining visual acuity. Post-operative care is required to support the restored bleb function. Our findings support the use of scleral patch graft as an effective and safe method for the long-term management of hypotony and bleb leak as a late complication of glaucoma filtration surgery.

Clinical and ASOCT evaluations of 'bleb-sparing epithelial exchange' in paediatric and adult dysfunctional blebs over 5 years

PURPOSE

To evaluate the long-term outcome of 'bleb-sparing epithelial exchange' surgery for dysfunctional filtering blebs in paediatric and adult eyes.

METHODS

Patients who had undergone bleb revision ≥ 5 years back and were on regular follow-up were included. Age, ocular diagnosis, details of primary filtering surgery including mitomycin-C (MMC) usage, indication and year of bleb revision were recorded. After bleb revision, the mean intraocular pressure (IOP), glaucoma medications and best corrected visual acuity (BCVA) up to 5 years were noted. On last review, clinical details, bleb characteristics and swept source anterior segment tomographic (SSOCT) assessment of bleb were recorded. Comparative analysis of paediatric and adult eyes was performed.

MAIN OUTCOME MEASURES

Change in IOP and BCVA. 'Complete success' was defined as IOP ≥ 6 to ≤ 18mmHg without use of any topical glaucoma medications and 'Qualified success' when ≥ 1 topical glaucoma medication(s) was required.

RESULTS

A total of 51 eyes of 51 consecutive patients were studied, among which 22 were children. The mean duration between filtering surgery and bleb revision was 4.54 ± 1.53 years in paediatric and 6.48 ± 3.5 years in the adult group, p = 0.04. Children underwent trabeculotomy + trabeculectomy with 0.04% MMC, while adults underwent trabeculectomy with 0.02% MMC. The mean pre-revision IOP was 6.38 ± 2.80 and 6.51 ± 2.78 mmHg in the paediatric and adult group respectively, p = 0.86. At 3 months post-revision, it increased to 11.81 ± 3.48 and 12.75 ± 3.52 mmHg respectively (p < 0.001). At final review, mean IOP of paediatric group was 10.90 ± 2.59 and adult group was 11.86 ± 2.66 mmHg, p = 0.20. At 5 years, complete success was 68.18% and 72.41%, and qualified success was 31.87% and 27.59% in the former and latter group respectively, p = 0.49. No failures were seen. Kaplan-Meier probability at 5 years for IOP target ≤ 18, ≤ 15 and ≤ 12 in children was 95.45%, 63.64% and 50% and in adults 93.10%, 65.52% and 41.38% respectively. BCVA improved up to 1 year in paediatric group, with continued improvement in adults up to 3 years. SSOCT measured bleb height was 0.88 ± 0.37 and 1.32 ± 0.49mm in children versus adults (p = 0.006) and wall thickness, 0.35 ± 0.22 and 0.58 ± 0.24mm respectively, p = 0.008.

CONCLUSION

Bleb-sparing epithelial exchange is an equally safe and effective technique with good long-term success in both paediatric and adult dysfunctional blebs.

The Translaminar Pressure Gradient: Papilledema After Trabeculectomy Treated With Optic Nerve Sheath Fenestration

INTRODUCTION

Trans-lamina cribrosa pressure has been postulated to be a contributor in the development of a glaucomatous optic nerve versus optic nerve edema, depending on the pressure gradient. Uncertainty remains in the therapeutic outcome of adjusting this gradient.

CASE REPORT

We discuss a unique case of idiopathic intracranial hypertension presenting as asymmetric optic disc edema following trabeculectomy. It was treated via optic nerve fenestration due to the patient remaining symptomatic on maximum tolerated acetazolamide. Intraocular pressure stabilized into target range and the optic nerve edema resolved.

CONCLUSIONS

Rarely, intraocular pressure reduction can unmask elevated intracranial pressure, leading to optic nerve edema. Optic nerve sheath fenestration is a practical therapeutic modality to consider when treating this occurrence.

Long-term Follow-up of Partial Bleb Excision in Late-onset Bleb-related Complications by a Single Surgeon Using Conjunctival Advancement

PURPOSE

The purpose of this study was to describe the long-term results of partial bleb excision in late-onset bleb-related complications by a single experienced surgeon using the same surgical technique.

PATIENTS AND METHODS

This was a retrospective study of 21 eyes of 11 women and 10 men aged 34 to 87 years (mean 64±12.8 y) who underwent first repair of late-onset bleb leaks with or without numerical hypotony (NH) and dysesthesia. The surgical technique consists of removing nonviable conjunctiva until the functional tissue becomes visible, thus adapting to individual conditions, and later conjunctival advancement. Complete success was defined as maintenance of intraocular pressure control without additional bleb revision, surgery, or glaucoma medications. Qualified success met these criteria, but with glaucoma medications.

RESULTS

The mean follow-up was 5.6±4.4 years (1 to 17 years). Sixty-two percent of the cases were considered complete success, and a moderate number of cases (19%) needed glaucoma medication for achieving qualified success at the end of the follow-up period. Interestingly, bleb leak with NH seems to have long-term outcomes, like the other bleb-related complications (in terms of success and failures), with a significant intraocular pressure increase at 1 month after revision that tended to remain within normal values and lead to visual acuity recovery without recurrent NH.

CONCLUSIONS

Partial bleb excision seems to be a good technique for different late-onset bleb-related complications. Bleb leak with NH showed a good long-term response, like the other bleb revision indications.