Outcome and Complications of Combined Modified Deep Sclerectomy and Trabeculectomy for Surgical Management of Glaucoma: A Pilot Study.

PURPOSE: To report the outcome and complications of a combined surgical technique of modified deep sclerectomy and trabeculectomy (mDST) for glaucoma. PATIENTS AND METHODS: Retrospective study of 44 eyes of 43 patients with open and closed angle glaucoma who underwent mDST. Outcome measures were: Surgical Success with 3 criteria - (i) criterion 1 = intraocular pressure (IOP) ≤21 mmHg or reduced by ≥20% of pre-operative IOP or IOP ≥6 mmHg on 2 consecutive time points after 3 months; (ii) criterion 2 = IOP ≤18 mmHg or reduced by ≥30% of pre-operative IOP or IOP ≥6 mmHg on 2 consecutive time points after 3 months and (iii) criterion 3 = IOP ≤15 mmHg or reduced by ≥40% of pre-operative IOP or IOP ≥6 mmHg on 2 consecutive time points after 3 months; IOP Reduction; Use of Anti-glaucoma Medication; Complications; Visual Acuity and Postoperative Interventions. RESULTS: Median follow-up was 40 months (range 24-77 months). At the final follow-up visit, the mean postoperative IOP was 11.5 ± 4.7 mmHg (p<0.0001). Mean number of anti-glaucoma medications decreased from 2.45 ± 1.21 to 0.54 ± 0.95 (p<0.0001). Surgical success in terms of IOP reduction was 50%; 43.2%; 36.4% for the 3 criteria respectively (complete success) and 70.5%; 56.8%; 47.7% for the 3 criteria respectively (qualified success). The complications noted were shallow/flat anterior chamber in 2 (4.54%), hyphema & bleb leak in 3 (6.81%), aqueous misdirection in 1 (2.27%), hypotonic maculopathy in 2 (4.45%) and hypotony requiring intervention in 6 (13.63%) eyes. CONCLUSION: Combined mDST was found to be an effective surgical procedure in reducing IOP. It was associated with complications commonly encountered in glaucoma filtering surgery. The use of intra-scleral space maintainer may help lower the risk of flat or shallow anterior chamber during the early postoperative period.

Phacoemulsification vs phacoemulsification with micro-bypass stent implantation in primary angle closure and primary angle closure glaucoma: A randomized single-masked clinical study.

IMPORTANCE: Primary angle closure glaucoma (PACG) is a major cause of irreversible visual impairment in Asia, but there is no published data on the effect of iStent on these patients. BACKGROUND: To compare the efficacy and safety of combined phacoemulsification and iStent implantation with standard phacoemulsification in an Asian population. DESIGN: A prospective, single-masked, randomized study in a public tertiary eye clinic. PARTICIPANTS: Patients with concomitant visually significant cataracts and primary angle closure (PAC) or PACG. METHODS: Patients were randomized and underwent either phacoemulsification alone (phaco) or with concurrent iStent injection (phaco-iStent). Demographic and clinical data were collected. MAIN OUTCOME MEASURES: Complete and qualified success rates at 12 months were compared between both treatment arms. RESULTS: Thirty-two patients were recruited between September 2015 and February 2016. All patients completed 12 months of follow-up. There was no statistically significant difference in preoperative IOP (phaco, 17.5 ± 3.1 mmHg; phaco-iStent, 18.6 ± 4.7 mmHg, P = .65) and 12-months postoperative IOP (phaco, 15.0 ± 2.5 mmHg; phaco-iStent, 14.7 ± 3.1 mmHg, P = .86) between both groups. Complete success rates were 43.8% (95% CI, 19.8-65.6) for the Phaco group and 87.5% (95% CI, 58.6-96.7) for the Phaco-iStent group (P = .01). Thinner preoperative optical coherence tomography (retinal nerve fibre layer) thickness (hazard ratio [HR] = 7.34 [95% CI, 1.53-35.30]) and phacoemulsification alone (HR = 0.93 [95% CI, 0.87-0.02]) were independent factors associated with failure to achieve complete success. CONCLUSIONS AND RELEVANCE: Combined phacoemulsification with iStent implantation is associated with a higher likelihood of complete success compared with phacoemulsification alone in eyes with primary angle closure disease at 12 months postoperatively. Further studies are required to establish the longer term efficacy of iStent implantation and to identify other predictors for surgical success.

Young's Modulus Determination of Normal and Glaucomatous Human Iris.

Purpose: To evaluate the biomechanical properties (Young's modulus) of normal (control) and glaucomatous human iris using atomic force microscopy (AFM). Methods: Iris tissue obtained from eighteen glaucomatous subjects (equal number of eyes with primary angle closure glaucoma (PACG) and primary open angle glaucoma (POAG) and five normal subjects who underwent elective eye surgery were subjected to the estimation of Young's modulus by AFM. Force measurements were done at room temperature using Nanowizard II BioAFM. The iris samples were immersed in the liquid media (PBS with 0.1% BSA) during force measurements. Young's modulus values were calculated for each recorded curve using JPK Data Processing Software, which uses a Hertz's contact model for spherical indenters fitted to the extend curves. Results: The iris from the normal controls had the least Young's modulus (0.85 ± 0.31 kPa) while those from PACG patients had the highest Young's modulus (2.40 ± 0.82 kPa). The Young's modulus of PACG iris was significantly higher compared to that of the normal controls (P = 0.005) and POAG iris (P = 0.001). However, there was no significant difference in the Young's modulus of POAG iris (1.13 ± 0.36 kPa) compared to that of the normal controls (P = 0.511). Conclusions: Variations in biomechanical properties of iris tissue may have a significant role in the pathogenesis of angle closure glaucoma. This study suggests the existence of fundamental biomechanical differences in eyes with angle closure versus open angle glaucoma. An understanding of this basis creates a new platform to understand disease pathology better and work on therapeutic strategies that will address the same.

Case Series of Combined iStent Implantation and Phacoemulsification in Eyes with Primary Angle Closure Disease: One-Year Outcomes.

PURPOSE: To evaluate the safety and efficacy of combined iStent® trabecular micro-bypass device (Glaukos, Laguna Hills, CA) and phacoemulsification in eyes with primary angle closure disease. METHODS: A two-center prospective interventional case series of consecutive patients with primary angle closure (PAC) or primary angle closure glaucoma (PACG) on at least one glaucoma medication, who underwent iStent implantation with cataract surgery. Postoperatively, patients were assessed on days 1 and 7, and months 1, 3, 6, and 12. The intraocular pressure (IOP), glaucoma medication use, visual acuity, and the presence of complications were assessed at each visit. Complete success was defined as IOP reduction of at least 20% without the use of glaucoma medications. RESULTS: Thirty-seven eyes with angle closure disease were included in this study. At 1-year, postoperative mean IOP (14.8 ± 3.94 mmHg) was significantly decreased compared with preoperative medicated (17.5 ± 3.82 mmHg, p = 0.008) and unmedicated (24.6 ± 3.41 mmHg, p < 0.001) IOP. Complete success was achieved in 89.2% of the eyes. The number of glaucoma medications decreased from 1.49 ± 0.77 to 0.14 ± 0.48 (p < 0.001). Preoperative medicated IOP was a risk factor for failure (hazard ratio 3.45, 95% confidence interval 1.52-7.85, p = 0.003), after adjustment for age, gender, and race. The most common postoperative complications were iStent occlusion with iris (27.0%) and hyphema (18.9%). There were no sight-threatening intraoperative or postoperative complications. CONCLUSION: Combined iStent implantation with cataract surgery was effective in lowering the IOP and the number of glaucoma medications for at least 12 months, with a favorable safety profile. FUNDING: Glaukos Corporation; NMRC Science Translational and Applied Research (STAR) award.

Ophthalmia due to spitting cobra venom in an urban setting--a report of three cases.

To describe three presentations of spitting cobra venom induced ophthalmia in urban Singapore. Case notes and photographs of three patients with venom ophthalmia who presented to our clinic between 2007 and 2012 were reviewed. Two patients encountered the spitting cobra while working at a job site while the third patient had caught the snake and caged it. The venom entered the eyes in all 3 cases. Immediate irrigation with tap water was carried out before presenting to the Accident and Emergency department. All patients were treated medically with topical antibiotic prophylaxis and copious lubricants. The use of anti-venom was not required in any case. All eyes recovered with no long-term sequelae. If irrigation is initiated early, eyes can recover with no significant complications or sequelae.

Survey on the knowledge of age-related macular degeneration and its risk factors among Singapore residents.

PURPOSE: To assess the awareness of age-related macular degeneration (AMD) and its risk factors among Singapore residents. METHODS: A cross-sectional questionnaire-based telephone survey was conducted to ascertain the awareness of AMD with regards to knowledge of the disease entity and possible risk factors among Singapore residents. A Singapore residential telephone directory was used to identify potential households by choosing the first and last entries on randomly selected pages. Respondents included individuals from households with landline telephone connection who were willing to participate in the study after a brief introduction about the study. Verbal consent was sought before proceeding with the interview. Interpreters were used for respondents whose ability to converse in English was limited. Prior to commencement of the study, the protocol was reviewed and approved by Ethics committee of the Domain Specific Review Board. RESULTS: The interviewers contacted 796 subjects from different households, of which 520 participated (response rate, 65.3%). The age of the respondents ranged from 18 to 85 (median 41) years. Only 38 (7.3%) of them were aware of AMD, the majority of whom had completed secondary or higher education. Two hundred (38.5%) and 191 (36.7%) of the respondents considered age and smoking, respectively, to be risk factors for AMD. CONCLUSIONS: The awareness of AMD among Singapore residents is low. AMD awareness needs to be improved by educational programmes designed for this specific purpose.

Resolution of an abnormal preferential hyperacuity perimetry test result resulting from epiretinal membrane after successful surgical removal.

PURPOSE: To report resolution of an abnormal preferential hyperacuity perimetry test result resulting from idiopathic epiretinal membrane after successful pars plana vitrectomy and membrane peeling. METHODS: An observational case report. PATIENT: A 51-year-old otherwise healthy woman presented with a gradual decrease in vision and metamorphopsia in her left eye for a duration of 3 months without any antecedent history of ocular surgery, trauma, or disorder. RESULTS: The Snellen best-corrected visual acuity was 20/80 at presentation resulting from an epiretinal membrane on the posterior pole in the left eye. The preferential hyperacuity perimetry test was abnormal preoperatively but after successful pars plana vitrectomy and membrane peeling, the abnormality resolved completely. The final best-corrected visual acuity was 20/30 at 14 weeks postoperatively along with improvement in her metamorphopsia. CONCLUSION: Epiretinal membrane can produce abnormal preferential hyperacuity perimetry findings that may disappear after its successful surgical removal. The preferential hyperacuity perimetry may be useful to monitor metamorphopsia in epiretinal membrane before and after surgery. Further investigation is warranted.

Laser treatment for retinopathy of prematurity through the incubator wall.

In this era of early treatment for retinopathy of prematurity, sick infants who develop aggressive diseases or remain oxygen and temperature dependent may be treated while they are inside the incubator itself, thus avoiding unnecessary delays. This article describes the treatment of eight infants with retinopathy of prematurity who were dependent on an incubator by using a laser indirect ophthalmoscope delivery system through the slanting transparent wall of the incubator. In this series, which is the largest to date, the relative advantages and disadvantages of the procedure are discussed.

Retinopathy of prematurity in Asian Indian babies weighing greater than 1250 grams at birth: ten year data from a tertiary care center in a developing country.

BACKGROUND: Retinopathy of prematurity (ROP) is an important cause of childhood blindness in developing countries. AIM: To report the spectrum of ROP and associated risk factors in babies weighing > 1250 g at birth in a developing country. SETTING AND DESIGN: Institutional, retrospective, non-randomized, observational clinical case series. MATERIALS AND METHODS: Retrospective analysis (10 years) of 275 eyes (138 babies) with ROP. STATISTICAL ANALYSIS: Qualitative data with the Chi-square test. Quantitative data using the unpaired t test or the ANOVA and further tested using multivariate logistic regression. RESULTS: The mean birth weight was 1533.9 g (range 1251 to 2750 g) and the mean period of gestation was 30.9 weeks (range 26 to 35). One hundred and twenty-four of 275 eyes (45.1%) had threshold or worse ROP. Risk factors for threshold or worse disease were, 'outborn babies' ( P P = 0.007) and exchange transfusion ( P = 0.003). The sensitivity of the American and British screening guidelines to pick up threshold or worse ROP in our study group was 82.4% and 77.4% respectively. CONCLUSIONS: Severe ROP is often encountered in babies weighing greater than 1250 g at birth in developing countries. Western screening guidelines may require modifications before application in developing countries.