Narayana Nethralaya

Bangalore, India

Narayana Nethralaya

Bangalore, India
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Shetty R.,Narayana Nethralaya | Deshpande K.,Narayana Nethralaya | Ghosh A.,GROW Research Laboratory | Sethu S.,GROW Research Laboratory
Cornea | Year: 2015

Purpose: To report the case of a 28-year-old patient with persistent bilateral burning pain and foreign body sensation in both eyes for the past 1 year. The patient showed a poor response to 0.05% cyclosporine eye drops and frequent instillations of artificial tears. Ocular examination showed few superficial punctate epithelial defects, well-positioned laser in situ keratomileusis (performed 5 years ago with symptomless recovery) flaps, and clear interfaces bilaterally, with a tear film breakup time of 7 and 8 seconds in the right and left eyes, respectively. The results of Schirmer tests, confocal microscopy, corneal esthesiometry, and meibography were normal for both eyes. The patient was incidentally diagnosed with vitamin B12 deficiency, with a serum vitamin B12 value of 90 pg/mL (reference range, 236-911 pg/mL), during routine laboratory tests. In view of weak correlation between signs and symptoms, a putative diagnosis of ocular neuropathic pain secondary to vitamin B12 deficiency was made. Methods: Case report. Results: The patient was treated with parenteral vitamin B12, and topical therapy was continued without any changes. The patient experienced dramatic improvement with a decrease in symptoms within 3 weeks of administering vitamin B12 supplements and was symptom-free in the absence of any topical medication 6 months after treatment. Conclusions: Vitamin B12 deficiency, although common in India, has not been reported to be associated with ocular symptoms, including pain and mimicking those seen in severe dry eye. Vitamin B12 deficiency should be considered in the differential diagnosis of ocular neuropathic pain and dry eye in patients presenting with recalcitrant ocular neuropathic pain. © 2015 Wolters Kluwer Health, Inc. All rights reserved.


Shetty R.,Narayana Nethralaya | Shetty R.,India Stem Cell Research Laboratory | Shetty R.,Maastricht University | Shetty R.,Stem Cell Research Laboratory | Shetty R.,GROW Laboratory
The British journal of ophthalmology | Year: 2015

AIM/BACKGROUND: To compare the effects of accelerated corneal collagen cross-linking (ACXL) and corneal collagen cross-linking (CXL) on ex vivo-cultured limbal epithelial cells (LECs).METHODS: Day 14 cultured LECs were either unexposed (control) or exposed to different intensities of ultraviolet-A (UV-A) irradiance for different durations (3 mW for 30 min, 9 mW for 10 min, 18 mW for 5 min and 30 mW for 3 min) in the presence and absence of riboflavin. These cells were further processed for quantitative real-time PCR, vital staining, immunofluorescence staining and fluorescence-activated cell sorting (FACS) staining to evaluate the apoptotic status. Statistical analysis was performed using a Student t test.RESULTS: Vital staining showed a significantly higher (p=0.004) dead cell population with 3 mW for 30 min when compared with 30 mW for 3 min exposure (p=0.225). Quantitative PCR results revealed significantly reduced abcg2 and Δnp63 mRNA levels, while FACS analysis showed an increase in ABCG2-Annexin V positive population in cells exposed to 3 mW for 30 mins. Neither reduction of mRNA expression of abcg2 and Δnp63 nor increase in FACS-stained ABCG2-Annexin V positivity was detected in cells exposed to 30 mW for 3 min. Additionally, enhanced caspase activity was detected with fluorochrome inhibitor of caspases staining and mRNA expression of caspase 3 and 9 was upregulated in cells exposed to 3 mW for 30 min, but not at 30 mW for 3 min.CONCLUSIONS: The 30 mW UV-A irradiation used in ACXL appears to be safe on cultured LECs in comparison with 3 mW used in CXL. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.


Dabir S.S.,Narayana Nethralaya | Das D.,Stem Cell Research Laboratory | Nallathambi J.,Narayana Nethralaya | Mangalesh S.,Narayana Nethralaya | And 2 more authors.
Indian Journal of Ophthalmology | Year: 2014

Introduction: Diabetic macular edema (DME) is a vision-threatening complication of diabetic retinopathy. The current practice of management is a" trial and error "method of using intravitreal antivascular endothelial growth factor (VEGF)" or steroids to treat the patient and watch the response. However, if the patient's genetic profile helps us choose appropriate medicine, it would help customize treatment option for each patient. This forms the basis of our study. Materials and Methods: A case-control, prospective, observational series, where DME patients were treated with bevacizumab and subclassified as treatment näve, treatment responders, and treatment nonresponders. Blood samples of 20 subjects were studied, with five patients in each of the groups (nondiabetic-group 1, treatment näve-group 2, treatment responder-group 3, and treatment nonresponder-group 4). Whole blood RNA extraction followed by labeling, amplification and hybridization was done, and microarray data analyzed. Genes were classified based on functional category and pathways. Results: The total number of genes upregulated among all three experimental groups was 5, whereas 105 genes were downregulated. There were no common genes upregulated between the responders and nonresponders. There was only one gene upregulated between the diabetic and diabetic responders posttreatment. There were 19 genes upregulated and 8 genes downregulated in the inflammatory pathway in group 2 versus group 1. There were no downregulated genes detected in vascular angiogenesis and transcription group. There were identical numbers of genes up-and downregulated in the inflammatory pathway. Seventeen genes were upreguated and 11 genes downregulated in receptor activity, which remained the predominant group in the group classification. Discussion: In summary, this study would provide an insight into the probable signaling mechanisms for disease pathogenesis as well as progression. This type of study eventually would aid in developing or improvising existing treatment modules with a rational approach towards personalized medicine, in future addressing the differential responses to treatment.


Matalia H.,Stem Cell Research Laboratory | Shetty R.,Narayana Nethralaya | Dhamodaran K.,Stem Cell Research Laboratory | Subramani M.,Stem Cell Research Laboratory | And 2 more authors.
British Journal of Ophthalmology | Year: 2012

Aim/background: To study the effects of ultraviolet-A (UV-A) irradiation, in the presence or absence of riboflavin, on ex vivo cultured limbal epithelial cells (LECs). Methods: The study was carried out in a super specialty ophthalmic hospital. Ex vivo cultured LECs were grown on denuded amniotic membranes and exposed to similar levels of UV-A radiation used during corneal cross-linking (CXL), in the presence or absence of the photosensitiser, riboflavin. These cells were then used for extraction of RNA, cDNA conversion, and antibody staining. Quantitative PCR and immuno fluorescence staining were performed to evaluate the apoptotic state of treated and non-treated LECs. Statistical analyses were evaluated using a Student's t test. Results: We found that bcl-2, an antiapoptotic gene, was downregulated, whereas, bax, a proapoptotic gene, was upregulated. After LECs were exposed to UV-A radiation, a significant upregulation of both caspase 3 and caspase 9 was observed in treated cells when compared with untreated LECs. Conclusions: These results indicate that exposure of LECs to UV-A dosages similar to those used in the CXL procedure promotes the expression of genes known to promote apoptosis. In the presence of riboflavin, the damage caused by UV-A treatment was marginalised, but not totally blocked.


Shetty R.,Narayana Nethralaya | Arora V.,Narayana Nethralaya | Jayadev C.,Narayana Nethralaya | Nuijts R.M.M.A.,Maastricht University | And 3 more authors.
Investigative Ophthalmology and Visual Science | Year: 2014

Purpose. To assess the repeatability and agreement of three rotating Scheimpflug cameras, Pentacam, Galilei, and Sirius, in measuring the mean keratometry (Km), thinnest corneal thickness (TCT), anterior chamber depth (ACD), and mean posterior keratometry (pKm) in keratoconus patients in a prospective study. Methods. Fifty-five eyes of 55 patients with keratoconus underwent three consecutive scans on each machine, performed by a single operator. Within-subject standard deviation (Sw), test-retest repeatability (TRT), and coefficient of variation (COV) for assessing repeatability and Bland-Altman plots for the agreement between the mean measurements of each machine were examined. Results. The Sw of Km and pKm measurements with Pentacam (0.23 and 0.10 diopters [D], respectively) were significantly lower (better) than those of Galilei (0.60 and 0.17) and Sirius (0.23 and 0.36). The Sw of TCT measurements with Sirius (8.88 μm) was significantly lower than that of Galilei (11.64 μm). The COV ranged between 0.5 for the Km measurements of Pentacam and 2.8 for the TCT measurements of Galilei. Significant proportional bias in agreement was detected for the pKm measurements with all the three device pairs and for the ACD measurements between Pentacam and Galilei and between Galilei and Sirius. Conclusions. Though Pentacam, Galilei, and Sirius showed repeatable measurements for Km, TCT, ACD, and pKm, repeatabilities with Pentacam and Sirius were better than those with Galilei. There were significant differences in the measurements between the three devices; hence they cannot be used interchangeably for anterior segment measurements in keratoconus patients. © 2014 The Association for Research in Vision and Ophthalmology, Inc.


Shetty R.,Narayana Nethralaya | Nuijts R.M.M.A.,Maastricht University | Nicholson M.,Narayana Nethralaya | Sargod K.,Narayana Nethralaya | And 4 more authors.
American Journal of Ophthalmology | Year: 2015

Purpose To evaluate the effect of keratoconus cone location on the change in refractive outcomes, corneal aberrations, and biomechanics after combined topography-guided photorefractive keratectomy (PRK) and collagen cross-linking (CXL). Design Prospective, comparative case series. Methods Topography-guided PRK was performed followed by accelerated CXL using riboflavin A and enhanced-intensity (30 mW/cm2) ultraviolet light. Outcome parameters including uncorrected distance visual acuity (UDVA) and best-corrected distance visual acuity (BDVA), corneal tomography and biomechanics (corneal hysteresis [CH] and corneal resistance factor [CRF]), and corneal wavefront aberrations were assessed before and a year after the procedure. Eyes were subdivided into 2 groups preoperatively for statistical analysis: Group 1, cone located within the central 2-mm zone; and Group 2, cone located outside the central 2-mm zone. Results UDVA, BDVA, sphere, cylinder, and simulated keratometry improved after treatment in both groups (P <.05). However, BDVA improved more in Group 1 than in Group 2 (P =.04) and the other variables were not affected by cone location. A few corneal wavefront Zernike aberrations changed after treatment (P <.05) but none were affected by cone location (P >.05). CH and CRF increased after treatment in both groups (P >.05). Interestingly, the increases in CH and CRF were greater in Group 2 than in Group 1 (P >.05). Conclusions Cone location appeared to impact only visual acuity and biomechanics after the combined procedure. The greater increase in CH and CRF in Group 2 may indicate differences in the ablation profile and variability in CXL outcomes and requires further study. © 2015 Elsevier Inc.


Battu R.,Narayana Nethralaya | Khanna A.,Narayana Nethralaya | Hegde B.,Forus Health | Berendschot T.T.J.M.,Maastricht University | And 2 more authors.
Eye (Basingstoke) | Year: 2015

PurposeTo correlate the structure of the macula, as measured by spectral-domain optical coherence tomography (SD-OCT) and function, as measured by microperimetry (MAIA) in patients with retinitis pigmentosa (RP) and relatively good visual acuity.DesignProspective, cross-sectional, non-intervention study.SubjectsPatients with RP.MethodsThirty patients with RP and good central visual acuity were identified. Each patient underwent SD-OCT of the macula and microperimetry. The images were overlaid using the custom-designed software. The retinal sensitivity by microperimetry was correlated with corresponding retinal thickness, as measured by the SD-OCT. ELM, COST, and IS/OS junction were scored as intact, disrupted, or absent.Main outcome measuresComparing the retinal sensitivity on the MAIA with various measurements on the SD-OCT.ResultsThe retinal sensitivity on the MAIA showed a significant correlation with total retinal thickness and outer retinal thickness on the SD-OCT. There was no association with either the inner retinal thickness or the choroidal thickness. ORT showed a statistically significant correlation with the anatomical classification of ELM (r=-0.76, P<0.001), IS/OS (r=-0.800, P<0.001), and COST (r=-0.733, P<0.001).ConclusionThis study determined that there was a high correlation of the structure and function of the central macula in patients with RP. These studies are important to establish surrogate markers that can be used as end points for various tests in future therapeutic clinical trials. © 2015 Macmillan Publishers Limited.


Battu R.,Narayana Nethralaya | Dabir S.,Narayana Nethralaya | Khanna A.,Narayana Nethralaya | Kumar A.K.,Narayana Nethralaya | Roy A.S.,Narayana Nethralaya
Indian Journal of Ophthalmology | Year: 2014

Adaptive optics is a relatively new tool that is available to ophthalmologists for study of cellular level details. In addition to the axial resolution provided by the spectral-domain optical coherence tomography, adaptive optics provides an excellent lateral resolution, enabling visualization of the photoreceptors, blood vessels and details of the optic nerve head. We attempt a mini review of the current role of adaptive optics in retinal imaging. PubMed search was performed with key words Adaptive optics OR Retina OR Retinal imaging. Conference abstracts were searched from the Association for Research in Vision and Ophthalmology (ARVO) and American Academy of Ophthalmology (AAO) meetings. In total, 261 relevant publications and 389 conference abstracts were identified.


Shivanna Y.,Narayana Nethralaya | Nagaraja H.,Narayana Nethralaya | Kugar T.,Narayana Nethralaya | Shetty R.,Narayana Nethralaya
Indian Journal of Ophthalmology | Year: 2013

Purpose: To assess the efficacy and advantages of femtosecond laser enabled keratoplasty (FLEK) over conventional penetrating keratoplasty (PKP) in advanced keratoconus. Materials and Methods: Detailed review of literature of published randomized controlled trials of operative techniques in PKP and FLEK. Results: Fifteen studies were identified, analyzed, and compared with our outcome. FLEK was found to have better outcome in view of better and earlier stabilization uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), and better refractive outcomes with low astigmatism as compared with conventional PKP. Wound healing also was noticed to be earlier, enabling early suture removal in FLEK. Conclusions: Studies relating to FLEK have shown better results than conventional PKP, however further studies are needed to assess the safety and intraoperative complications of the procedure.


Yadav N.K.,Narayana Nethralaya | Jayadev C.,Narayana Nethralaya | Mohan A.,Narayana Nethralaya | Vijayan P.,Narayana Nethralaya | And 4 more authors.
Eye (Basingstoke) | Year: 2015

PurposeTo assess the safety and efficacy of a single session of subthreshold micropulse (SM) yellow laser (577 nm) in the treatment of chronic central serous chorioretinopathy (CSCR).MethodsThis was a retrospective analysis of 15 eyes of 13 patients with CSCR of >3 months duration who had been treated with SM yellow laser (577 nm). All patients had been treated using multiple spots of laser with a duty cycle of 10% over areas of focal and diffuse leak, as seen on fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA). Reduction in subretinal fluid height on spectral domain optical coherence tomography (SD-OCT) was used to measure the response to treatment.ResultsThe mean follow-up was at 8 weeks (4-19 weeks). All eyes responded to treatment. The mean subretinal fluid height pre and post treatment was 232 and 49 μm, respectively, showing a 79% average reduction (P<0.001) in fluid height. There was no evidence of retinal pigment epithelium or retinal damage on SD-OCT, FFA, or fundus autofluorescence. Median visual improvement was one line on Snellen's visual acuity chart (P=0.015). Microperimetry was performed in eight eyes of which six eyes (75%) showed an improvement in the threshold values post treatment.ConclusionSM yellow laser is an effective treatment option for chronic CSCR. © 2015 Macmillan Publishers Limited. All rights reserved.

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