Comparison of conjunctiva-related complications between scleral and corneal patch grafts in Ahmed glaucoma valve implantation

Purpose: Comparison of the conjunctiva related complication rates and success rates among eyes with Ahmed glaucoma valve (AGV) implantation in which eye bank derived scleral and corneal patch grafts had been used to cover the tube. Methods: Retrospective comparative study. Patients who underwent AGV implantation between January 2000 to December 2016 were included. Demographic, clinical data, intra and post operative data was obtained from electronic medical records. Conjunctiva related complications were divided into two groups: with and without implant exposure. Conjunctiva related complication rates, success rate, risk factors among eyes with corneal and scleral patch graft were compared. Results: Three hundred and twenty three eyes of 316 patients underwent AGV implantation. Scleral patch graft was used in 214 eyes of 210 patients (65.9%) and corneal patch graft was used in 109 eyes of 107 patients (34%). Median follow up was 14 months. There was no significant difference in the conjunctiva related complication rate (7.3 % in corneal patch graft versus 7.0% in scleral patch graft;p=0.5) and conjunctival dehiscence rate (3.7% versus 4.6%, P = 0.7) among the two groups. Success rate was significantly higher in the corneal patch graft group versus the scleral patch graft group (98% versus 72%; p=0.001). Eyes with corneal patch graft had a higher survival rate (P = 0.01). Conclusion: There was no significant difference in the rate of conjunctiva related complications following corneal and scleral patch grafts used to cover the AGV tube. Eyes with corneal patch graft had a higher success rate and survival rate.

Etiology and epidemiological analysis of glaucoma-filtering bleb infections in a tertiary eye care hospital in south India.

Purpose: To evaluate the microbial etiology and associated risk factors among patients with blebitis following trabeculectomy. Materials and Methods: A retrospective analysis of all culture-proven blebitis was performed in patients who underwent trabeculectomy between January 2004 and December 2008. A standardized form was filled out for each patient, documenting sociodemographic features and information pertaining to risk factors. Swabbing of the infected bleb surface was performed for all suspected cases and further subjected to microbiological analysis. Results: A total of 23 patients with culture-proven blebitis were treated during the study period, with a mean age of 59.2 years (59.2 ± SD: 12.8; range, 30-81 years). Duration of onset was early (≤36 months) in six (26%) cases and late (> 36 months) in 17 (74%) cases with a range between 15 and 144 months (mean, 82.91 months; SD: 41.89). All 23 blebs were located superiorly and of which, 21 (91%) were microcystic avascular, 1 (4%) diffuse avascular, and 1 (4%) vascular flattened. The predominant risk factor identified was bleb leak (35%; 8 of 23) followed by thin bleb (22%; 5 of 23) and blepharitis (17%; 4 of 23). Bleb leaks (100%) were recorded only in patients with late onset (≥ 9 years) of infection (P< 0.001), while the incidence of ocular surface disease (100%) occurred early (≤3 years) (P< 0.001). Use of topical steroids was associated frequently with cases of thin blebs (80%; 4 of 5) (P< 0.001), while topical antibiotics showed bleb leaks (88%; 7 of 8) (P< 0.001). Coagulase-positive staphylococci were frequently recovered from blebitis with thin blebs (71%; 5 of 7) (P = 0.001), Coagulase-negative staphylococci (CoNS) with bleb leak (100%; 8 of 8) (P< 0.001), Corynebacterium with blepharitis (100%; 3 of 3) (P = 0.001), and Streptococci with releasable sutures (75%; 3 of 4) (P = 0.001). Conclusion Bleb leak is the principal risk factor responsible for late-onset blebitis, while early-onset blebitis could be ascribed to ocular surface diseases. Streptococci were mainly responsible for early onset of infection, while the late onset was due to CoNS.

Surgical management of glaucoma: An Indian perspective.

Glaucoma is a serious sight-threatening disorder aptly named the Silent thief of sight. India, being the second most populous country in the world, has about 20% of the world glaucoma population. The complex geographical and socioeconomic architecture and the economic extremes have a profound effect on its health system. The present times are abundant with fresh developments in the field of glaucoma. Though newer modalities are present in India, they are not ample and are unequally distributed. Adherence and persistence with medical therapy is an issue owing to a multitude of factors. In such a setting, most of the ophthalmologists find themselves performing glaucoma surgeries quite often. In the present era, there are a number of new surgeries to choose from, especially procedures which are nonpenetrating and blebless. Faced with a spectrum of surgeries from shunts to canal surgeries and trabecular bypass devices, the surgeon is often in a dilemma. Still, trabeculectomy remains the gold standard with an increasing trend toward glaucoma drainage devices. The new procedures and devices are worth exploring but await long-term results, good training of surgeons and cost effectiveness.