Raja Narayanan

A randomised, double-masked, controlled study of the efficacy and safety of intravitreal bevacizumab versus ranibizumab in the treatment of macular oedema due to branch retinal vein occlusion: MARVEL Report No. 1

Purpose To assess the efficacy and safety of intravitreal bevacizumab (IVB) compared with ranibizumab (IVR) in the treatment of macular oedema due to branch retinal vein occlusion (BRVO). Methods In this prospective, randomised, non-inferiority trial, 75 participants with macular oedema due to BRVO received intravitreal injections of ranibizumab or bevacizumab after 1:1 block randomisation. The primary outcome measure was the difference in mean changes in best-corrected visual acuity (BCVA) at 6 months. Secondary outcome measures included mean change in central retinal thickness (CRT), the proportion of patients improving by >15 letters and the proportion of patients developing neovascularisation. Results Participants received either IVR (n=37) or IVB (n=38). The mean BCVA at baseline was 52.8±14.4 letters (20/80) and 56.1±10.0 letters (20/80) (p=0.24) in the ranibizumab and bevacizumab groups, respectively. At 6 months, the mean gains in BCVA were +18.1 letters (p<0.0001; 95% CI, +12.8 to +22.6) in the ranibizumab group and +15.6 letters (p<0.0001; 95% CI +12.0 to +20.5) in the bevacizumab group. The difference between the mean visual gains of the treated groups (bevacizumab–ranibizumab) was −2.5 letters (95% CI −8.0 to +5.0; p=0.74). Mean reductions in CRT at 6 months were 177.1±122.3 µm in the ranibizumab group (p<0.0001) and 201.7±166.2 µm in the bevacizumab group (p<0.0001), with no significant difference between the two groups (p=0.48). The mean numbers of ranibizumab and bevacizumab injections were 3.2±1.5 and 3.0±1.4, respectively (p=0.55). Two serious adverse events occurred in the ranibizumab group and one in the bevacizumab group but both were unrelated to intravitreal injections. Conclusions This study demonstrated significant gain in visual acuity in eyes with BRVO treated with either bevacizumab or ranibizumab. Pro-re-nata strategy was effective in maintaining the visual gain. Trial registration number http://www.ctri.nic.in/ CTRI/2012/01/003120.

Idiopathic macular hole surgery with low-concentration infracyanine green-assisted peeling of the internal limiting membrane.

PURPOSE To evaluate the efficacy of pars plana vitrectomy with infracyanine green (IFCG)-assisted internal limiting membrane peeling for the treatment of idiopathic macular hole. DESIGN Prospective, noncomparative interventional case series. METHODS Thirty-eight consecutive eyes of 35 patients with idiopathic macular hole were included in the study. Patients underwent early treatment diabetic retinopathy (ETDRS) visual acuity examination, dilated ophthalmoscopy, and optical coherence tomography before treatment and during follow-up. Fluorescein angiography was done in selected cases. Patients underwent a three-port pars plana vitrectomy with complete posterior hyaloid and epiretinal membrane removal. The internal limiting membrane (ILM) was stained with 0.5 cc of IFCG (0.5 mg/ml, 308 mOsm) and peeled up to the vascular arcades. Perfluoropropane gas (C(3)F(8)) 10% was used as tamponade. RESULTS Mean follow-up duration was 10 +/- 5 months (range, 3 to 24 months). Six eyes had stage 2 macular hole, 15 eyes stage 3, and 16 eyes stage 4. Overall, 37 of 38 macular holes closed after a single surgery. Median visual acuity was 20/100 (range, 20/400 to 20/50) before surgery and 20/50 (range, 20/640 to 20/25) after surgery. Visual acuity after surgery was 20/50 or better in 24 of 38 (63.1%) eyes. Twenty-five (65.8%) eyes improved by 2 or more lines, nine (23.7%) eyes were stable, and four (10.5%) eyes worsened by 2 or more lines. CONCLUSIONS This study suggests that IFCG (0.05%) effectively stains the ILM with apparent safety, and that IFCG-assisted peeling of the ILM may be useful in the treatment of idiopathic macular hole.

Genetic analysis of Indian families with autosomal recessive retinitis pigmentosa by homozygosity screening.

PURPOSE To identify the disease-causing genes in families with autosomal recessive RP (ARRP). METHODS Families were screened for homozygosity at candidate gene loci followed by screening of the selected gene for pathogenic mutations if homozygosity was present at a given locus. A total of 34 families were included, of which 24 were consanguineous. Twenty-three genes were selected for screening. The presence of homozygosity was assessed by genotyping flanking microsatellite markers at each locus in affected individuals. Mutations were detected by sequencing of coding regions of genes. Sequence changes were tested for presence in 100 or more unrelated normal control subjects and for cosegregation in family members. RESULTS Homozygosity was detected at one or more loci in affected individuals of 10 of 34 families. Homozygous disease cosegregating sequence changes (two frame-shift, two missense, and one nonsense; four novel) were found in the TULP1, RLBP1, ABCA4, RPE65, and RP1 genes in 5 of 10 families. These changes were absent in 100 normal control subjects. In addition, several polymorphisms and novel variants were found. All the putative pathogenic changes were associated with severe forms of RP with onset in childhood. Associated macular degeneration was found in three families with mutations in TULP1, ABCA4, and RP1 genes. CONCLUSIONS Novel mutations were found in different ARRP genes. Mutations were detected in approximately 15% (5/34) of ARRP families tested, suggesting involvement of other genes in the remaining families.

Hyaluronidase for Pharmacologic Vitreolysis

Various pharmacologic vitreolysis agents, including hyaluronidase, urea, plasmin, dispase, tissue plasminogen activator and chondroitinase have been tested. Pharmacologic vitreolysis can avoid the complications of surgery such as cataract, endophthalmitis, retinal hemorrhage, tear or detachment, and anesthesia related complications. Hyaluronan is a major macromolecule of vitreous. It is a long, unbranched polymer of repeating disaccharide (glucuronic acid beta (1,3)-N-acetylglucosamine) moieties linked by beta 1-4 bonds. Hyaluronan is covalently linked to a protein core, to form a proteoglycan. It plays a pivotal role in stabilizing the vitreous gel. Hyaluronidase cleaves glycosidic bonds of hyaluronic acid and, to a variable degree, other acid mucopolysaccharides of the connective tissue. Dissolution of the hyaluronic acid and collagen complex results in decreased viscosity of the extracellular matrix. This in turn increases the diffusion rate of erythrocytes and exudates along with phagocytes through the vitreous and facilitates red blood cell lysis and phagocytosis.

Microbiologic spectrum and susceptibility of isolates in acute postcataract surgery endophthalmitis: are they same as they were more than a decade ago?

Endophthalmitis is a severe and vision-threatening complication of intraocular surgeries like cataract surgery. Treatment of endophthalmitis includes vitreous tap/biopsy to identify the etiologic organisms and prompt initiation of broad-spectrum intravitreal antibiotics. The choice of initial broad-spectrum antibiotics is based on the susceptibility patterns of micro-organisms in a particular region. The purpose of the current study was to investigate the spectrum of organisms causing culture-proven acute postcataract surgery endophthalmitis and their antimicrobial susceptibilities at our centre between 2006 and 2013, and to compare the results with the previously published data from the same centre.1 This was a retrospective, non-comparative, consecutive case series. Microbiology records were reviewed of all the culture-proven, acute postcataract surgery endophthalmitis cases treated at L V Prasad Eye Institute, Hyderabad, India, between January 2006 and March 2013. Bacterial isolates were identified using Analytical Profile Index (API, Bio Meriux, France). The susceptibility was determined by the Kirby–Bauer disk diffusion method. …

Short-term outcome of Boston Type 1 keratoprosthesis for bilateral limbal stem cell deficiency

This study reports the short-term functional and anatomical outcome of Boston Type 1 keratoprosthesis (Boston Kpro) implantation for bilateral limbal stem cell deficiency (LCSD). Retrospective analysis was done on eight eyes of eight patients who underwent Boston Kpro implantation between July 2009 and October 2009. The best corrected visual acuity (BCVA) and slit-lamp biomicroscopy findings were assessed at 1, 3 and 6 months postoperatively. All eight eyes retained the prosthesis. BCVA of 20/40 or better was achieved in 8, 6, and 5 eyes at 1, 3, and 6 months, respectively, postoperatively. One patient each developed epithelial defect, sterile stromal melt and fungal keratitis in the late postoperative period associated with antecedent loss of the soft contact lens from the eye. Boston Kpro has good short-term visual and anatomical outcome in patients with bilateral LSCD, provided compliance with postoperative care can be ensured.

Fundus autofluorescence patterns in type 2A idiopathic juxtafoveolar retinal telangiectasis

Purpose To describe fundus autofluorescence (FAF) patterns in patients with type 2A idiopathic juxtafoveolar retinal telangiectasia (IJRT). Methods We reviewed FAF images, color photographs, and fluorescein angiography (FA) images of 30 eyes from 16 patients with type 2A IJRT. Eyes with presence of subretinal neovascularization or any other retinal pathology were excluded. All the imaging modalities were obtained with a Heidelberg Retina Angiograph (HRA) confocal laser scanning system. Results The mean age of the patients was 50.7 years, 68.5% female. At baseline, the median best-corrected visual acuity was 20/50. Loss of normal foveal hypoautofluorescence was noted in 93.3% of eyes. All the eyes showed hypoautofluorescence corresponding to intraretinal crystals and pigment clumps. Increased FAF around the pigments was noted in 93.3% of eyes. Increased FAF corresponding to the angiographic leakage from telangiectatic and nontelangiectatic areas was noted in 86.6% of eyes and 80% of eyes, respectively. Conclusions Loss of foveal hypoautofluorescence and increased FAF corresponding to the nontelangiectatic angiographic leakage areas were predominant features. Fundus autofluorescence patterns corresponding to color photography and FA findings may further add to the understanding of morphologic alterations in type 2A nonproliferative IJRT at early stages.

Traumatic endophthalmitis caused by Staphylococcus gallinarum.

Herein, we describe what we believe to be the first case of traumatic endophthalmitis caused by Staphylococcus gallinarum, following injury with an iron nail. The patient was successfully treated by vitrectomy and intravitreal injection of cefazolin and vancomycin.

Two years follow-up outcome of verteporfin therapy for subfoveal choroidal neovascularization in pathologic myopia in Indian eyes.

Context: In India, refractive errors are a major cause of treatable blindness. Population surveys in southern India have shown prevalence of high myopia to be 4.32-4.54%. Photodynamic therapy (PDT) for choroidal neovascularization (CNV) caused by pathologic myopia is beneficial. Aims: To report the 24 months outcome of PDT with verteporfin for subfoveal CNV caused by pathologic myopia in Indian eyes Settings and Design: Prospective case series Materials and Methods: Review of prospectively collected data of Indian patients with pathologic myopia and subfoveal CNV treated with verteporfin therapy between 2001 and 2005 using standard regimen for PDT. Statistical Analysis Used: Wilcoxon signed rank test was used to see the difference in the mean letter acuity at intervals compared to baseline. Kaplan Meier Survival analysis was done to estimate the success rate of verteporfin therapy for CNV caused by pathologic myopia. Results: Fifteen patients (15 eyes) treated with standard fluence PDT and who had completed 24 months follow-up were analyzed. The mean spherical equivalent was -13.36 ± 5.88 diopter. Five out of 15 eyes in six months, three out of 15 eyes at 12 months and four eyes out of 15 at 24 months had improved vision by > 10 letters. The mean number of treatment session was 2.2 in two years. Conclusions: PDT with verteporfin for subfoveal CNV caused by pathologic myopia in Indian eyes is effective.

Characterization of idiopathic macular telangiectasia type 2 by fundus fluorescein angiography in Indian population

Purpose To characterize the variations in fundus fluorescein angiography (FFA) features in idiopathic macular telangiectasia (IMT) type 2. Methods Retrospective observational study. The authors included all the patients with IMT type 2 who underwent FFA during the period from January 2004 to December 2005. The main outcome measures were subretinal neovascularization and number and distance of telangiectasia from the center of the foveal avascular zone. Results The mean age of 21 patients included in the study was 53.0±7.7 years. There were 11 women and 10 men. Six of the 21 patients had a history of diabetes mellitus. Subretinal neovascularization (SRN) was observed in 10 (23.8%) eyes. Subretinal plaque of pigment hyperplasia in the macula was found in 7 (21.9%) eyes, and crystalline yellowish deposits on the retinal surface were seen in 19 (59.4%) eyes. Only one eye had visible retinal telangiectasia. Most had more than 10 telangiectatic lesions in the macular area and the temporal macula was most commonly involved. The mean distance from the center of the foveal avascular zone (FAZ) up to which telangiectasia could be observed was 1340±400 μm. The maximum distance from the FAZ at which telangiectasia was identified was 2530 μm. Conclusions In IMT type 2, telangiectasia may be seen farther from the parafoveal area.