Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Hema L. Ramkumar is active.

Publication


Featured researches published by Hema L. Ramkumar.


Journal of Nutrition | 2013

Nutrient Supplementation with n3 Polyunsaturated Fatty Acids, Lutein, and Zeaxanthin Decrease A2E Accumulation and VEGF Expression in the Retinas of Ccl2/Cx3cr1-Deficient Mice on Crb1rd8 Background

Hema L. Ramkumar; Jingsheng Tuo; De F. Shen; Jun Zhang; Xiaoguang Cao; Emily Y. Chew; Chi-Chao Chan

The Age-Related Eye Diseases Study 2 (AREDS2) clinical trial is assessing the effects of higher dietary xanthophyll (lutein and zeaxanthin) and long-chain n3 polyunsaturated fatty acid (LCPUFA) docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) intake on progression to advanced age-related macular degeneration (AMD). This studys purpose was to examine the retinal effects of the AREDS2 formulation on Chemokine (C-C motif) ligand 2 (Ccl2(-/-))/CX3C chemokine receptor 1 (Cx3cr1(-/-)) mice on Crumbs homolog 1 retinal degeneration phenotype 8 (Crb1(rd8)) background (DKO), which develop focal retinal lesions with certain features similar to AMD. DKO and C57BL/6N rd8 background mice (WT) were bred and randomized into 4 groups. Two groups, WT mice on AREDS2 diet (A-WT) and DKO mice on AREDS2 diet (A-DKO), were supplemented daily with 1.76 μmol of lutein, 35.1 μmol of zeaxanthin, 215 μmol EPA, and 107 μmol of DHA, and 2 control groups, WT mice on control diet (C-WT) and DKO mice on control diet (C-DKO), were fed an isocaloric diet. All mice had monthly fundus photos and were killed after 3 mo for biochemical and histologic analyses. After 3 mo, 81% of A-DKO mice had lesion regression compared with 25% of C-DKO mice (P < 0.05). Toxic retinal 2-[2,6-dimethyl-8-(2,6,6-trimethyl-1-cyclohexen-1-yl)-1E,3E,5E,7E-octatetra-enyl]-1-(2-hydroxyethyl)-4-[4-methyl-6(2,6,6-trimethyl-1-cyclohexen-1-yl) 1E,3E,5E,7E-hexatrienyl]-pyridinium (A2E) concentrations were significantly lower in A-DKO compared with C-DKO mice. The outer nuclear layer thickness in A-DKO mice was significantly greater than that in C-DKO mice. Retinal expression of inducible nitric oxide synthase (iNos) tumor necrosis factor-α (Tnf-α), Cyclooxygenase-2 (Cox-2), interleukin1beta (IL-1β), and vascular endothelial growth factor (Vegf) was significantly lower in A-DKO compared with C-DKO mice. Xanthophylls and LCPUFAs have antiinflammatory, neuroprotective, and antiangiogenic properties. Our data provide potential mechanisms by which the AREDS2 formula has a protective effect on retinal lesions in DKO mice.


Retina-the Journal of Retinal and Vitreous Diseases | 2017

LONG-TERM REMISSION OF NEOVASCULAR AGE-RELATED MACULAR DEGENERATION WITH AS-NEEDED ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY.

Ilkay Kilic Muftuoglu; Mostafa Alam; Qi Sheng You; Raouf Gaber; Hema L. Ramkumar; Nadia Mendoza; Amit Meshi; William R. Freeman

Purpose: To determine the presenting characteristics of patients with neovascular age-related macular degeneration with long-term remission (LTR), which was defined as the absence of intraretinal/subretinal fluid, or hemorrhage, and absence of leakage on fluorescein angiography for longer than 6 months while on as-needed antivascular endothelial growth factor treatment. Methods: The presenting characteristics of patients with LTR were compared with a control group including 32 eyes of 28 age-, gender-, and ethnicity-matched patients who did not achieve LTR. Results: Seventy-four percent of patients in the LTR group had Type 1 choroidal neovascular membrane and 18.5% had retinal angiomatous proliferation. In the control group, 28 eyes had Type 1 choroidal neovascular membrane (87.5%), and none of the patients had retinal angiomatous proliferation; overall, there was a significant difference in lesion types between the 2 groups (P = 0.036). Eyes with LTR at presentation had significantly thinner subfoveal choroidal thickness (147 vs. 178 &mgr;m, P = 0.04). There was more intraretinal fluid and less subretinal fluid at the presentation in the remission group (59.3% intraretinal fluid and 11.1% subretinal fluid) compared with the control group (28.1% intraretinal fluid and 34.4% subretinal fluid, P = 0.03). Conclusion: The presence of retinal angiomatous proliferation, thinner choroidal thickness, more intraretinal fluid, and less subretinal fluid at presentation were associated with LTR in patients receiving as-needed treatment for age-related macular degeneration.


Survey of Ophthalmology | 2016

A baby with a lot of nerve

Hema L. Ramkumar; Rohan Verma; Janet Crow; Shira L. Robbins; David B. Granet; Claire A. Sheldon; Fred M. Henretig; Grant T. Liu

An infant presented with bilateral disk edema and an acute left sixth cranial nerve (CN VI) palsy because of pseudotumor cerebri (PTC). PTC is rare in infants where it is often associated with endocrine abnormalities, medications, viral infections, systemic conditions, and nutritional etiologies such as vitamin A toxicity. We report a case of PTC in an infant associated with hypervitaminosis A with an unlikely source-a common prenatal vitamin.


Survey of Ophthalmology | 2017

Optic nerve head problem

Rohan Verma; Kevin C. Chen; Hema L. Ramkumar; Michael H. Goldbaum; Carol L. Shields

A 68-year-old woman with a recent history of blurring in the left eye had undergone mastectomy for breast cancer 20 years ago. A series of bone metastases started 5 years after her diagnosis. Examination of the optic nerve head of the left eye revealed an isolated peripapillary mass. Indocyanine green angiography displayed vessels within the mass, and fluorescein angiography demonstrated hyperfluorescence of the mass from vascular leakage plus lobular spots of blocked fluorescence. B-scan ultrasound revealed a hyperechoic-elevated nodular mass on the optic disc. Spectral-domain optical coherence tomography displayed a mass of spherules. Magnetic resonance imaging of the brain demonstrated metastatic tumors. She was diagnosed with an optic disk metastasis from her breast carcinoma.


Journal of Clinical & Experimental Ophthalmology | 2017

Sutured Versus Sutureless Sclerotomies after 25 Gauge Vitrectomy without an Internal Tamponade

Ilkay Kilic Muftuoglu; Mark Espina; Frank S. Tsai; Hema L. Ramkumar; Michael H. Goldbaum; William R. Freeman

Objective: We wished to determine whether suturing of 25 gauge sclerotomies was advantageous in maintaining normal intraocular pressure (IOP) or preventing hypotony after 25-gauge vitrectomy in eyes not requiring internal tamponade.Methods: Two-hundred seventeen consecutive 25-gauge vitrectomy surgeries from 2010 to 2013 performed at a single center by two surgeons were retrospectively reviewed. Patients were divided into 2 groups based on the surgeons routine use of suture in such cases. Surgeon 1 (sutureless group) did not suture any sclerotomies unless intra-operative leakage was noted and surgeon 2 (sutured group) sutured all 25 gauge sclerotomies routinely. Patient data was retrieved from charts and from this we determined the mean IOP change from baseline, hypotony incidence, and complications.Results: There was no significant difference in the mean IOP change at any postoperative visits (p=0.18 at postop day 1, p=0.3 at postop week 2, p=0.23 at postop 1 month, and p=0.43 at postop month 3) between the two groups. The hypotony rate was 10.9% in surgeon 1 and 9% in surgeon 2 group at postoperative day 1 (p=0.82). One patient required suture placement at postoperative day 1 in sutureless group. No complications were seen related with hypotony at any groups.Conclusion: In our population, there is no increased risk of hypotony with sutureless transconjunctival 25-gauge vitrectomy. Suturing of non-leaking 25-gauge wounds has no effect on complications from hypotony.


Current Ophthalmology Reports | 2017

X-Linked Idiopathic Infantile Nystagmus (XLIIN): Case Report and Review of Literature

Rohan Verma; Hema L. Ramkumar; Kang Zhang; David B. Granet; Richard W. Hertle

AbstractᅟInfantile nystagmus syndrome (INS) is one of the most common forms of nystagmus. It can occur in isolation or with other ocular anomalies. While nystagmus is usually sporadic, familial cases exist and are most commonly X-linked with incomplete penetrance and variable expressivity. There are over 45 mutations reported in the FRMD7 gene.Purpose of ReviewThis review describes the possible underlying mechanisms of infantile nystagmus syndrome, clinical characterization, and principles of management including behavioral, refractive, pharmacological, and surgical options as well as determines the genetic basis of INS in one large Caucasian family with a novel mutation in FRMD7.Recent FindingsNewer generation optical coherence tomography (OCT) allows for accurate phenotypical characterization of genetic subtypes of INS.SummaryFurther studies into identifying unknown genetic mutations involved in infantile nystagmus syndrome will allow for development of cellular and animal models to help classify INS and guide future therapies.


British Journal of Ophthalmology | 2016

Visual phenomena perceived during pars plana vitrectomy under peribulbar block and monitored anaesthesia care

Hema L. Ramkumar; Azadeh Khatibi; William R. Freeman; Giulio Barteselli; Isaac Ezon; Payam Amini; Lucie Sharpsten; Cheryl A. Arcinue; Joseph T Nezgoda; Henry A. Ferreyra; Michael H. Goldbaum

Aim To investigate patients’ sensory phenomena, especially instrument visualisation, and their emotional reactions during pars plana vitrectomy (PPV) under monitored anaesthesia care (MAC). Methods One hundred adults who underwent PPV under MAC plus peribulbar block were prospectively recruited on the day after surgery to complete a questionnaire about sensory phenomena and comfort. Anaesthetics used during surgery were correlated with visual phenomena and patient comfort. Surgeons were asked to predict patient intraoperative comfort and ability to hear. Results Of the 27% of patients who reported visual phenomena, lights (74%), colours (37%) and moving instruments (17%) were common. Instrument visualisation was not associated with any preoperative or intraoperative variables. Visual phenomena were neutrally received by 98% of patients. Neither the use of the intravenous medications during the peribulbar injection and surgery nor the type of local anaesthesia correlated with perceived level of pain. Sixty-six per cent of patients remembered hearing surgeons talk, and 96% of patients reacted neutrally to voices. Patient reports of intraoperative pain were similar to the surgeons prediction, and mean discomfort during surgery was mild. Conclusions The reported prevalence of intraoperative visual phenomena is low when elicited at the first postoperative visit. Surgeons can reliably predict patients’ comfort, and most patients react neutrally to visual and hearing phenomena during PPV under MAC with peribulbar block. The combination of medications used may be responsible for the neutral reception of sensory phenomena.


Indian Journal of Ophthalmology | 2014

Toxic optic neuropathy: An unusual cause

Hema L. Ramkumar; Peter J. Savino

A 60-year-old woman with a history of chronic alcoholism and tobacco use presented with the complaint of a painless decrease in vision in both eyes. She lost vision first in the left eye then in the right eye. She admitted consuming at least one 16 ounce bottle of over the counter mouthwash daily and denied consumption of any other alcohols, methanol, or antifreeze. She stated that her vision had been continuing to deteriorate in both eyes. Her best-corrected visual acuity was 4/200 in each eye. Color vision was nil in each eye. Her pupils were sluggish bilaterally, and her optic discs were flat and hyperemic with peripapillary hemorrhages. Her visual fields revealed central scotomas bilaterally. The magnetic resonance imaging of the brain and lumbar puncture were within normal limits. Antinuclear antibody, human leukocyte antigen-B27 genotyping, and B12 were normal; serum thiamine was low. While continuing to ingest mouthwash, her vision decreased to count fingers at 2 feet, and maculopapillary bundle pallor developed. She was started on folate and thiamine supplementation. Once she discontinued mouthwash, her vision improved to 20/400 bilaterally, and her central scotomas improved. This case demonstrates an alcohol-induced toxic optic neuropathy from mouthwash ingestion with some visual recovery after discontinuation of the offending agent.


Indian Journal of Ophthalmology | 2014

A novel mutation in a case of dominant optic atrophy

Hema L. Ramkumar; Peter J. Savino

A 39-year-old healthy woman presented for decreased vision at distance and near for 4 years. She also noted a decrease in her color vision. Her best-corrected visual acuities were 20/70 in each eye. Her visual fields were abnormal, and she had bilateral sluggish pupils, impaired color vision, and optic disc pallor. The magnetic resonance imaging of the brain, heavy metal screen, autoimmune work-up, B12, B6, folate, erythrocyte sedimentation rate, rapid plasma reagin, and Lyme titer were all normal. Optical coherence tomography of the macula and electroretinogram were normal; the visual evoked potential was unrecordable in both eyes. She denied a family history of similar ocular issues, and genotyping of the OPA1 gene revealed a novel previously unreported mutation at IVS12+10T >C.


Journal of Oncology | 2013

A Clinical Update and Radiologic Review of Pediatric Orbital and Ocular Tumors

Ajay A. Rao; John H. Naheedy; James Y.-Y. Chen; Shira L. Robbins; Hema L. Ramkumar

Collaboration


Dive into the Hema L. Ramkumar's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Rohan Verma

University of California

View shared research outputs
Top Co-Authors

Avatar

Amit Meshi

University of California

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Raouf Gaber

University of California

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Qi Sheng You

Capital Medical University

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge