Outcomes of Ahmed glaucoma valve surgery performed by glaucoma fellows - A large retrospective study from Eastern India.

PURPOSE: Teaching and training of glaucoma fellows on the technique of Ahmed glaucoma valve (AGV) implantation surgery is very important. The purpose of this study was to describe the clinical outcomes and complications of AGV surgery performed by glaucoma fellows of a tertiary eye center from eastern India. METHODS: This was a retrospective study based on electronic medical records. Thirty-five eyes operated with AGV by five glaucoma fellows from January 2016 to November 2020 were included. Best-corrected visual acuity, intraocular pressure (IOP), and number of antiglaucoma medications (AGMs) were the study outcome measures. RESULTS: The mean (±standard deviation) age of the patients was 40.5 (±19.7) years. The follow-up period was 24.37 (±13.01) months. Both complete success (IOP <21 mmHg without additional AGM) and qualified success (IOP <21 mmHg with an additional AGM) were achieved in eight eyes each (22.8%). Failure of the surgery was noted in 19 eyes (54.3%) as there was a need for repeat surgery for IOP control in 12 eyes and a persistent IOP spike (IOP >21 mmHg with AGM beyond 3 months) in seven eyes. Despite a high rate of failure of the primary surgery, with the consultants' intervention, there was statistically significant improvement in vision and IOP in all patients ( P < 0.01) at the last follow-up. CONCLUSION: AGV implantation is a challenging surgical skill to be acquired by the glaucoma fellows.

Outcomes of reimplantation of a new Glaucoma Drainage Device after explantation of an older implant from exposure-related complications.

Purpose: To describe the clinical outcome of a series of seven eyes with an explanation of an original Glaucoma Drainage Device (GDD) arising from the complication of plate exposure and consequent reimplantation of another GDD at a second setting. Methods: This was a retrospective, interventional, and non-comparative study at two tertiary eye care hospitals in eastern and southern India. Electronic medical record data of the seven eyes where a GDD was explanted and a 2nd GDD was reimplanted over October 2010 and May 2021 was analyzed. Statistical analysis was done by SPSS (ver. 26). Results: The first GDD survived for a mean of 168 days only till the plate got exposed and thereby got explanted. Possible predisposing factors noted were conjunctival and scleral thinning, ischemic conjunctiva, etc., The reimplantation surgery was technically easy in the absence of hypotony-opposite to what is reported in the literature. The final IOP (mean +/- SD) values (mm Hg) were 18.9 (+/-7.9), range = 10-30. The mean number of glaucoma medications reduced from 3.9 (+/-1.2; range, 2 to 5) after the explanation to 3.1 (+/-0.7; range, 2 to 4) after the 2nd GDD implantation, in the final follow-up. The second GDD was found to be stable till the last follow-up (mean = 1149 days). No other significant intraoperative or postoperative complications were seen. Conclusions: Reimplantation of a second GDD in a separate setting after explanations of an original implant due to exposure-related complication is both a safe and effective method.

Evaluating perspective and quality of life of glaucoma patients during the COVID-19 pandemic in India: Results of a telephone survey.

Purpose: The past few years have been difficult in the lives of most glaucoma patients in view of the COVID-19 pandemic. Our aim was to find out patients' perspective and disruption of their quality of life during the COVID-19 pandemic by conducting a telephone survey among glaucoma patients. Methods: This was a cross-sectional study involving the glaucoma patients of a tertiary eye care hospital in India. Patients who had completed at least five years of follow-up before 2020 were randomized by a random number generator. A validated (forward-backward translation and completed pilot analysis) set of 14 questionnaires was administered to the patients, the latter of whom were telephonically interviewed by one of the investigators in February 2022. The entire data was audio-recorded. Statistical Package for the Social Sciences (SPSS) version 26 was used. Results: Out of 1141 patients with >5 years of follow-up, 103 were selected by randomization. A large group of 46 patients (44.6%) admitted to glaucoma affecting their daily activities. Only 12 (11.6%) admitted to being irregular with their drops. Thirty-four (33%) patients felt that their glaucoma was deteriorating and 31 (30.1%) had fear of blindness. Ninety-five patients (92.7%) felt that they were safe under the care of the treating doctor. There were 46 (44.6%) out of 103 patients who did not turn up for follow-up for six months or more. Lockdown (36.2%) and travel-expenses (27.6%) were the two most common reasons for the loss to follow-up visits. Conclusion: Nearly half of the long-term glaucoma patients were lost to follow-up during the COVID-19 pandemic. Glaucoma affecting daily lives and fear of losing vision turned out to be significant observations in the telephone survey. This fear seemed to be ameliorated by the majority still feeling safe by being in touch with their doctor for continued care even during the COVID-19 pandemic.

Glaucoma screening skills among general ophthalmologists - How general should it be?

Purpose: To compare the glaucoma assessment skills among general ophthalmologists in their referral patients over 5 years. Methods: This was a retrospective auditing of the electronic medical record database. Details of consecutive new glaucoma patients seen in the glaucoma services of a tertiary eye care institute in 2013 and 2018 were collected. Details of each patient included the clinical presentation, baseline intra-ocular pressure (IOP), type and severity of glaucoma, referral details, gonioscopy, HVF (Humphrey visual field) data, and the number of medications. Statistical tests used were the Chi-square test and T test using SPSS version 22. Results: Of 28,886 medical records screened, 211 and 568 new glaucoma patients were retrieved in 2013 and 2018, respectively. The patients presenting in 2018 were younger (58.1 ± 15.4 years) at presentation than in 2013 (65.6 ± 15.2 years), P < 0.01, and also had higher baseline IOP (IOP ≥40 mm Hg was found in 9.5% in 2018 versus 2.4% in 2013; P < 0.01). The percentage of eyes with presenting visual acuity worse than 20/400 or 20/600 was higher in the patients presenting in 2018 (22.2% vs. 15.1%; P = 0.03). Although primary glaucoma predominated in both periods, the number of eyes referred to as disc suspects showed an increase in 2018 (4.7% to 14.4%; P < 0.01). Among 195 and 517 referrals in 2013 and 2018, respectively, the documentation of clinical findings were dismally poor in both the groups in terms of absent gonioscopy (99% vs. 98.2%, P = 0.4), absent disc details (89.6% vs. 91%, P = 0.5), or absent visual field analysis (79.1% vs. 74.8%, P = 0.2). However, the missing IOP values were significantly better in the latter year (77.3% vs. 57.2%; P < 0.01). Conclusion: The increase in the number of new glaucoma patients and referrals did not show a corresponding improvement in documentation of findings except for IOP recording among general ophthalmologists. Hence, we need to re-emphasize the training of general ophthalmologists on basic glaucoma evaluation to improve their referral ability.

Vessel Caliber in Normal Tension and Primary Open Angle Glaucoma Eyes With Hemifield Damage.

PURPOSE OF THE STUDY: The purpose of the study was to evaluate retinal vessel diameter in age-matched normal tension glaucoma (NTG) and primary open angle glaucoma (POAG) eyes with hemifield involvement. METHODS: Fundus photographs of patients with hemifield defect, good visibility of retinal nerve fiber layer defect, and vessels were compared with 30 controls. One eye of each patient (28 NTG and 30 POAG) was randomly chosen for analysis using Image J software by different clinicians at 2 levels. The structural parameters analyzed included retinal nerve fiber layer defect width, diameter of vessels (superotemporal or inferotemporal artery and superotemporal or inferotemporal vein). RESULTS: The average superotemporal artery diameter was similar in NTG (71±16.8 µm), POAG (79±26.6 µm), and controls (82±14.1 µm), P=0.2 with similar pattern seen for other vessels. The affected quadrant in all eyes and those with disc hemorrhage (n=8) did not have significantly different arteries and veins diameter as compared with the unaffected quadrant in that eye. No relation of artery or vein diameter with retinal nerve fiber layer defect width or clinical variables in NTG or POAG eyes was seen on multivariate regression analysis. CONCLUSIONS: The vessel diameter was not significantly different in the affected and unaffected quadrants of age and severity-matched NTG and POAG eyes with hemifield structural and functional defect as reported in earlier studies. These results point toward the possibility that vascular diameter changes may not be the cause for glaucomatous changes.

Central Field Index Versus Visual Field Index for Central Visual Function in Stable Glaucoma.

OBJECTIVE: To compare the variability of central field index (CFI) versus visual field index (VFI) in stable glaucoma with central fixation involvement. MATERIALS AND METHODS: For this retrospective study, we identified multiple visual fields (VFs) of patients with repeatable central fixation involvement on Humphrey VFs (24-2 and 10-2 program) which were stable (clinically and on VFs) over a very short period of 2 to 3 months. The VFI and CFI were calculated as described in earlier reports. We graded the fields as early [mean deviation (MD)>-6 dB], moderate (-6.1 to -12 dB), and severe glaucoma (<-12 dB) based on MD on 24-2 program. The variability of CFI and VFI between visits and across different severity of glaucoma was compared. Relation of the divergence to field indices and clinical parameters were assessed. RESULTS: The intervisit difference for VFI was greater than CFI ranging from -4% to 9% versus -1% to 8% in early (P=0.9), -13% to 18% versus -6% to 17% (P=0.056) in moderate, and -21% to 19% versus -9% to 9% (P<0.001) in severe glaucoma. The CFI within each group had narrower range than VFI with maximum range in severe glaucoma (33% to 95%). The divergence of CFI from VFI started at MD 24-2 beyond (worse) -10 dB. This difference between CFI and VFI was associated significantly with number of points with P<1% on 24-2 (R=80.3%). CONCLUSIONS: CFI is less variable than VFI in stable eyes with fixation involvement especially in severe glaucoma indicating need for incorporating CFI calculation for monitoring advanced disease in eyes with central defects.