Ravi Keshavamurthy

• MD FRCS
• Kaiser Permanente

Optical coherence tomography (OCT) was introduced about two decades ago and has revolutionized ophthalmic practice in recent years. It is a noninvasive noncontact imaging modality that provides a high-resolution cross-sectional image of the cornea, retina, choroid and optic nerve head, analogous to that of the histological section. Advances in OCT...

Purpose:Measures of photoreceptor structure in regions unaffected by vitelliform lesions using spectral-domain optical coherence tomography (SD-OCT) in patients with Best Vitelliform Macular Dystrophy (BVMD) have reported conflicting results. Two different quantitative methods were used to compare photoreceptor layer thickness in areas adjacent to...

Purpose To establish normative data for macular volume by spectral-domain optical coherence tomography (SD-OCT) in subjects with no known retinal disease. Methods In an academic institutional setting, 50 subjects (age range 20–84 years) with no known retinal disease, best-corrected visual acuity 20/20, and normal intraocular pressure were enrolled...

To evaluate the outcomes of "concurrent vitrectomy" to retrieve dislocated lens fragment during phacoemulsification. In a retrospective, observational case series, data of patients who underwent "concurrent" pars plana vitrectomy (PPV) for dislocated lens fragments between the period 2000 and 2008 were reviewed. Data collected included patient demo...

Importance Retinal ischemia–induced upregulation of vascular endothelial growth factor (VEGF) leads to endothelial proliferation of the anterior segment, resulting in neovascular glaucoma.Objective To investigate the ciliary epithelium as a possible source of VEGF in human eyes enucleated for intractable neovascular glaucoma.Design, Setting, and...

Objective. To prospectively evaluate the effect of intravitreal bevacizumab on aqueous levels of interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) in patients with exudative age-related macular degeneration (AMD) and correlate clinical outcomes with cytokine levels. Methods. 30 eyes of 30 patients with exudative AMD underwent intra...

Objective. To prospectively evaluate the effect of intravitreal bevacizumab on aqueous levels of interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) in patients with exudative age-related macular degeneration (AMD) and correlate clinical outcomes with cytokine levels. Methods. 30 eyes of 30 patients with exudative AMD underwent intra...

Resveratrol, a polyphenolic phytoalexin present in red wine, has a protective role against tumor-induced angiogenesis. Exudative age-related macular degeneration is characterized by hypoxia-induced choroidal vascular endothelial cell (CVEC) proliferation. In this study, we evaluated the effect of resveratrol on hypoxic CVECs and the underlying sign...

Importance: Sickle cell disease (SCD) is characterized by vaso-occlusive crisis. In the eye, central retinal artery occlusion (CRAO) is a rare complication in SCD, with only 1 previous report of bilateral, concurrent CRAO. We report a case of bilateral, concurrent CRAO in a patient with SCD, possibly precipitated by the use of phosphodiesterase 5...

Context: Lutein (LUT) and zeaxanthin (ZEA) are currently under investigation in clinical trials as prophylactic nutritional agents for age-related macular degeneration (AMD). However, dose used in these trials is empirical and not been investigated in in vitro studies. Objective: In this study, we investigated the dose-response effect of LUT and...

Purpose: To evaluate the differential sensitivity of choroidal endothelial, retinal pigment epithelial, and retinal ganglion cells to escalating doses of proton beam radiation and to establish a safe dose range for the management of choroidal neovascularization associated with age-related macular degeneration (AMD). Design: Laboratory investigat...

To evaluate the procedural experience and complications of a novel integrated laser delivery system (NAVILAS(®); OD-OS Teltow, Germany) that combines automated laser delivery with color fundus photography, fluorescein angiography (FA), fundus autofluorescence (FAF) and infrared imaging with a frequency doubled YAG laser. This prospective study eval...

Purpose Pars plana vitrectomy with peeling of the internal limiting membrane is a well-established technique for the treatment of idiopathic macular holes with high success rates. Complications such as retinal tears may result from vitreous incarceration at the sclerotomy sites. Prophylactic laser retinopexy (LR) has recently been shown to decrease...

Spectral-domain optical coherence tomography findings in a patient with acute macular neuroretinopathy, and correlation with functional defects on microperimetry, are presented. A 25-year old Caucasian woman presented with bitemporal field defects following an upper respiratory tract infection. Her visual acuity was 20/20 in both eyes and a dilated...

Proton beam therapy offers the advantage of precise delivery with limited damage to the healthy tissue and is being tested in the management of exudative age-related macular degeneration (AMD). However, the dosages tested are empirical and not based on preclinical studies. In this study we evaluated the effects of varying doses of proton beam radia...

The purpose was to determine if birth weight (BW) alone can be the sole criterion for screening infants at risk for retinopathy of prematurity (ROP). In this retrospective, observational case series, 208 infants were screened for ROP using the American Association for Pediatric Ophthalmology and Strabismus (AAPOS) Guidelines (1997). Variables exami...

Vital dyes such as infracyanine green (IfCG), brilliant blue green (BBG), and bromophenol blue (BPB) have been used as an alternative to indocyanine green (ICG) during chromovitrectomy. We compared the in vitro toxicity of IfCG, BBG, and BPB with ICG on the retinal pigment epithelial cells and retinal ganglion cells at various concentrations to opt...

Histopathologic studies of sickle cell retinopathy and other vaso-occlusive diseases have previously shown selective atrophy of the inner retinal layers (ganglion cell layer, inner nuclear layer, and müllerian glia of the retina) in several eyes after retinal infarction.² Spectral-domain OCT provides high-resolution cross-sectional images that have...

Aqueous levels of vascular endothelial growth factor (VEGF) can be a surrogate marker of intraocular VEGF activity and a measure of efficacy of anti-VEGF treatment in a variety of vasoproliferative retinal disorders, including diabetic retinopathy, age-related macular degeneration, and central retinal vein occlusion. Measurement of the VEGF level m...

Focal epiretinal radiation has emerged as a promising tool in the management of choroidal neovascularization associated with age-related macular degeneration. However, the dosages tested are not backed by cell culture studies used in the clinical setting empirically. Choroidal endothelial cells (RF6A) were maintained in a log scale and exposed to a...

Sankarathi Balaiya Sandeep Grover Ravi K Murthy Kakarla V ChalamDepartment of Ophthalmology, University of Florida College of Medicine, Jacksonville, FL, USAPurpose: Aqueous levels of vascular endothelial growth factor (VEGF) can be a surrogate marker of intraocular VEGF activity and a measure of efficacy of anti-VEGF treatment in a variety of vaso...

Retinal pigment epithelial (RPE) tear has been described to occur spontaneously, after laser photocoagulation and in recent times, after intravitreal injection of anti-vascular endothelial growth factor (VEGF) agents. In the latter case, the rapid contraction of the choroidal vascular membrane underneath a serous RPE detachment is believed to be th...

Purpose: To describe the spectral-domain optical coherence tomography features in a patient with an atypical presentation of hypotonous maculopathy after successful retinal detachment surgery. Methods: A 64-year-old man underwent scleral buckling with pars plana vitrectomy for the repair of retinal detachment. Postoperatively, the retina was attach...

Vascular endothelial growth factor (VEGF) is well known for its role in pathologic neovascularization, including wet age-related macular degeneration. However, a growing body of evidence indicates that VEGF is also neuroprotective of non-vascular cells in various animal models through reduction of oxidative stress. In light of the widespread use of...

Optic nerve head drusen (ONHD) are white calcareous deposits, seen either superficially on the optic nerve head or buried within it. Diagnosis of ONHD is made by one or more ways: clinical exam, autofluorescence, ultrasound of the optic nerve, CT scan and/or visual field examination. The present study describes features of ONHD based on another dia...

The purpose of this study was to evaluate the accuracy of measurement of a known concentration of vascular endothelial growth factor (VEGF) using cytometric bead-based assay in microsamples (50 microL) and compare it with that obtained by enzyme-linked immunosorbent assay. A known concentration of VEGF samples was prepared with addition of VEGF (10...

Purpose To study the correlation between final visual acuity after successful anatomic macular hole repair and features on spectral domain optical coherence tomography (SD-OCT). Methods Retrospective review of charts of patients who underwent macular hole surgery. Data collection included pre- and postoperative best-corrected visual acuity (BCVA),...

Branch retinal artery occlusions (BRAO) are characterized histopathologically by inner retinal edema initially and atrophy in the presence of persistent ischemia. The duration of ischemia leading to irreversible atrophic retinal changes is not clear. Spectral-domain optical coherence tomography (SD-OCT) provides non-invasive detailed in-vivo histol...

The wide-angle viewing system during vitreoretinal surgery has lead to an increased success rate of complex procedures. Two types of wide-angle viewing systems are in use, contact and noncontact, each with its own advantages and disadvantages. In this article, we describe an optical system, OptiFlex, that is designed to combine the advantages of th...

Cystoid macular edema (CME) is an important cause of visual loss after cataract surgery. Treatment is usually with topical anti-inflammatory agents, with anti-vascular endothelial growth factor agents and steroids used intravitreally in resistant cases. Even though time-domain Stratus OCT can quantify the macular thickness, it cannot prognosticate...

Our study is aimed at evaluating the role of UVB light in inducing cytotoxicity in an in vitro model. RGC-5 and ARPE-19 cells were exposed to different time periods of UVB light: 0, 15, 30, and 45 min. They were subsequently examined for changes in cell morphology, cell viability (neutral red uptake assay), generation of reactive oxygen species (RO...

Sankarathi Balaiya, Ravi K Murthy, Vikram S Brar, Kakarla V ChalamDepartment of Ophthalmology, University of Florida College of Medicine, Jacksonville, FL, USAPurpose: Our study is aimed at evaluating the role of UVB light in inducing cytotoxicity in an in vitro model.Methods: RGC-5 and ARPE-19 cells were exposed to different time periods of UVB li...

Spectral-domain optical coherence tomography (SD-OCT) is an advancement over time-domain OCT (TD-OCT) in the imaging of retinal disorders. Retinal thickness measured by SD-OCT differs from that measured by TD-OCT because the delineation of the outer boundary of the retina differs in the two instruments. The present study aims to evaluate this diffe...

To evaluate in vitro the effects of bevacizumab, an anti-vascular endothelial growth factor (VEGF) antibody, on retinal pigment epithelial cells (RPE) and retinal ganglion cells (RGC), at doses that were inhibitory to VEGF-enriched choroidal endothelial cells (CEC). Monkey CEC (RF6A), human RPE cells (ARPE-19), and rat RGC (RGC-5) were exposed for...

Purpose To report fundus auto fluorescence (FAF) and spectral-domain optical coherence tomography (SD-OCT) findings in a patient with early hydroxychloroquine maculopathy. Methods A 50-year-old man presented with complaints of ring-like shadows in front of his eyes. He had been on hydroxychloroquine (Plaquenil) 400 mg orally twice daily for 10 yea...

A congenital anomaly, optic nerve pit is often associated with serous retinal detachment involving macula. Long standing serous detachment leads to outer retinal atrophy and decrease in visual sensitivity. Recently, spectral-domain optical coherence tomography (OCT) has been reported to demonstrate a communication between the optic nerve sheath and...

Background Indocyanine green (ICG) dye is commonly used to stain the inner limiting membrane during macular surgery. There are reports documenting the toxicity of ICG on retinal pigment epithelial cells, with conflicting results in retinal ganglion cells. In the present study, we evaluated the effect of ICG on retinal ganglion cells in vitro. Cultu...

Introduction Circumscribed choroidal hemangiomas are vascular tumors associated with secondary changes in the overlying retinal pigment epithelium and neuro-sensory retina. Spectral-domain optical coherence tomography, a recent advancement in fundus imaging techniques provides high resolution images of the retina. We describe spectral domain Optica...

A 14-year-old boy presented with decreased visual acuity in both eyes of three-months duration. Fundus examination revealed macular exudation in both eyes with aneurysmal changes at the arteriolar bifurcations. Fluorescein angiography confirmed the presence of numerous aneurysmal dilatations of the retinal arterioles and extensive peripheral capill...

To compare the clinical efficacy of lidocaine 2% with tetracaine 0.5% for cataract surgery. In a randomized, multi-surgeon, controlled clinical trial,122 consecutive cataract cases eligible for topical anesthesia, were randomly assigned to receive lidocaine 2% gel (1 ml) or tetracaine solution 0.5% (TetraVisc, 0.5 ml) before clear corneal phacoemul...

To establish normative data for macular volume by spectral-domain optical coherence tomography (SD-OCT) in subjects with no known retinal disease. In an academic institutional setting, 50 subjects (age range 20-84 years) with no known retinal disease, best-corrected visual acuity 20/20, and normal intraocular pressure were enrolled. The subjects we...

To describe a portable wide-field noncontact digital camera for posterior segment photography. The digital camera has a compound lens consisting of two optical elements (a 90-dpt and a 20-dpt lens) attached to a 7.2-megapixel camera. White-light-emitting diodes are used to illuminate the fundus and reduce source reflection. The camera settings are...

Corneal neovascularization contributes to corneal opacification in inflammatory conditions of the cornea and severely compromises the success of corneal transplantation. Vascular endothelial growth factor (VEGF) plays an important role in stimulating and maintaining corneal neovascularization. Anti-VEGF therapy, especially the use of anti-VEGF anti...

Sinonasal lymphoma, a rare nonepithelial malignant tumor often originates from the nose and paranasal sinuses. Typically, these lymphomas present with symptoms of nasal obstruction, discharge, epistaxis and facial swelling. Orbital extension results in ocular symptoms like proptosis, blurred vision and diplopia. In this case report, we describe per...

A case of aplastic anemia diagnosed during pregnancy, which developed bilateral disc edema and acute pre-retinal hemorrhage leading to vision loss. A 20 year old primagravid female developed acute vision loss in her right eye, during hospitalization for treatment of aplastic anemia diagnosed during her pregnancy. Her best-corrected visual acuity (B...

The use of corneal contact lens during vitreous surgery has been popular because it affords excellent visualization of the fundus.(1) The viewing systems have evolved from the traditional irrigating lens system to the use of contact lens which is placed in a sutured metal ring.(2) The sutures used to secure the ring have the potential to cause blee...

Purpose Cystoid macular edema is one of the important causes of visual loss in branch retinal vein occlusion. Proximity of the cyst to the external limiting membrane and disruption of the layer on time domain optical coherence tomography is associated with poor final visual outcomes. The authors describe pre- and post-intravitreal bevacizumab spect...

Nerve growth factor (NGF) helps in the healing and survival of ganglion cells, photoreceptors, and optic nerve after injury and has been implicated to have a role in pathophysiology of glaucoma. So far, in animal studies, injury to iris in vitro has revealed an increase in NGF levels in aqueous. There is a great interest in investigating the levels...

To report the occurrence of proliferative vascular retinopathy in two patients with polymyositis/dermatomyositis. Review of case records. One patient presented, six years after the diagnosis of polymyositis, with obliteration of the superior retinal vessels and associated neovascularization of the disc. The second patient with overlap syndrome was...

Transconjunctival Sutureless Vitrectomy (TSV) is a recent advancement in vitreo-retinal surgical techniques involving the use of 25 G instruments through self-sealing sclerotomies. It has been hypothesized that there may be less chance of vitreous and retinal herniation in the scleral wound as compared to conventional sclerotomy incision. However t...

Records of 37 consecutive patients of postoperative endophthalmitis referred to our centre from North India were retrospectively analysed to study the first contact management profile. Ten (27%) patients had received intravitreal antibiotics as a primary mode of treatment, and 27 (73%) had received only parenteral antibiotics. The outcome was worse...

Results of core vitrectomy in post-traumatic endophthalmitis are poor. Our initial results of complete vitrectomy with primary silicone oil endotamponade were promising. A comparative study of this procedure with conventional core vitrectomy was therefore carried out. A prospective randomized controlled study of 24 consecutive cases of post-traumat...