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Dive into the research topics where George Parlitsis is active.

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Featured researches published by George Parlitsis.


Retina-the Journal of Retinal and Vitreous Diseases | 2012

Ultra-wide-field angiography improves the detection and classification of diabetic retinopathy.

Matthew M. Wessel; Grant D. Aaker; George Parlitsis; Minhee Cho; Donald J. DʼAmico; Szilard Kiss

Purpose: To evaluate patients with diabetic retinopathy using ultra–wide-field fluorescein angiography and to compare the visualized retinal pathology with that seen on an overly of conventional 7 standard field (7SF) imaging. Methods: Two hundred and eighteen eyes of 118 diabetic patients who underwent diagnostic fluorescein angiography using the Optos Optomap Panoramic 200A imaging system were included. The visualized area of the retina, retinal nonperfusion, retinal neovascularization, and panretinal photocoagulation were quantified by two independent masked graders. The respective areas identified on the ultra–wide-field fluorescein angiography image were compared with an overly of a modified 7SF image as outlined in the Early Treatment Diabetic Retinopathy Study. Results: Ultra–wide-field fluorescein angiograms imaging, on average, demonstrated 3.2 times more total retinal surface area than 7SF. When compared with 7SF, ultra–wide-field fluorescein angiography showed 3.9 times more nonperfusion (P < 0.001), 1.9 times more neovascularization (P = 0.036), and 3.8 times more panretinal photocoagulation (P < 0.001). In 22 eyes (10%), ultra–wide-field fluorescein angiography demonstrated retinal pathology (including nonperfusion and neovascularization) not evident in an 7SF overly. Conclusion: Compared with conventional 7SF imaging, ultra–wide-field fluorescein angiography reveals significantly more retinal vascular pathology in patients with diabetic retinopathy. Improved retinal visualization may alter the classification of diabetic retinopathy and may therefore influence follow-up and treatment of these patients.


Clinical Ophthalmology | 2013

Comparison of ultra-widefield fluorescein angiography with the Heidelberg Spectralis® noncontact ultra-widefield module versus the Optos® Optomap®

Matthew T. Witmer; George Parlitsis; Sarju Patel; Szilard Kiss

Purpose To compare ultra-widefield fluorescein angiography imaging using the Optos® Optomap® and the Heidelberg Spectralis® noncontact ultra-widefield module. Methods Five patients (ten eyes) underwent ultra-widefield fluorescein angiography using the Optos® panoramic P200Tx imaging system and the noncontact ultra-widefield module in the Heidelberg Spectralis® HRA+OCT system. The images were obtained as a single, nonsteered shot centered on the macula. The area of imaged retina was outlined and quantified using Adobe® Photoshop® C5 software. The total area and area within each of four visualized quadrants was calculated and compared between the two imaging modalities. Three masked reviewers also evaluated each quadrant per eye (40 total quadrants) to determine which modality imaged the retinal vasculature most peripherally. Results Optos® imaging captured a total retinal area averaging 151,362 pixels, ranging from 116,998 to 205,833 pixels, while the area captured using the Heidelberg Spectralis® was 101,786 pixels, ranging from 73,424 to 116,319 (P = 0.0002). The average area per individual quadrant imaged by Optos® versus the Heidelberg Spectralis® superiorly was 32,373 vs 32,789 pixels, respectively (P = 0.91), inferiorly was 24,665 vs 26,117 pixels, respectively (P = 0.71), temporally was 47,948 vs 20,645 pixels, respectively (P = 0.0001), and nasally was 46,374 vs 22,234 pixels, respectively (P = 0.0001). The Heidelberg Spectralis® was able to image the superior and inferior retinal vasculature to a more distal point than was the Optos®, in nine of ten eyes (18 of 20 quadrants). The Optos® was able to image the nasal and temporal retinal vasculature to a more distal point than was the Heidelberg Spectralis®, in ten of ten eyes (20 of 20 quadrants). Conclusion The ultra-widefield fluorescein angiography obtained with the Optos® and Heidelberg Spectralis® ultra-widefield imaging systems are both excellent modalities that provide views of the peripheral retina. On a single nonsteered image, the Optos® Optomap® covered a significantly larger total retinal surface area, with greater image variability, than did the Heidelberg Spectralis® ultra-widefield module. The Optos® captured an appreciably wider view of the retina temporally and nasally, albeit with peripheral distortion, while the ultra-widefield Heidelberg Spectralis® module was able to image the superior and inferior retinal vasculature more peripherally. The clinical significance of these findings as well as the area imaged on steered montaged images remains to be determined.


Clinical Ophthalmology | 2010

Retinal nerve fiber layer evaluation in multiple sclerosis with spectral domain optical coherence tomography

Aziz A. Khanifar; George Parlitsis; Joshua R. Ehrlich; Grant D. Aaker; Donald J. D’Amico; Susan A. Gauthier; Szilard Kiss

Purpose: Histopathologic studies have reported retinal nerve fiber layer (RNFL) thinning in various neurodegenerative diseases. Attempts to quantify this loss in vivo have relied on time-domain optical coherence tomography (TDOCT), which has low resolution and requires substantial interpolation of data for volume measurements. We hypothesized that the significantly higher resolution of spectral-domain optical coherence tomography (SDOCT) would better detect RNFL changes in patients with multiple sclerosis, and that RNFL thickness differences between eyes with and without optic neuritis might be identified more accurately. Methods: In this retrospective case series, patients with multiple sclerosis were recruited from the Judith Jaffe Multiple Sclerosis Center at Weill Cornell Medical College in New York. Patients with a recent clinical diagnosis of optic neuritis (less than three months) were excluded. Eyes with a history of glaucoma, optic neuropathy (other than multiple sclerosis-related optic neuritis), age-related macular degeneration, or other relevant retinal and/or optic nerve disease were excluded. Both eyes of each patient were imaged with the Heidelberg Spectralis® HRA + OCT. RNFL and macular thickness were measured for each eye using the Heidelberg OCT software. These measurements were compared with validated published normal values, and were modeled as linear functions of duration of disease. The odds of an optic neuritis diagnosis as a function of RNFL and macular thickness were calculated. Results: Ninety-four eyes were prospectively evaluated using OCT. Ages of patients ranged from 26 to 69 years, with an average age of 39 years. Peripapillary RNFL thinning was demonstrated in multiple sclerosis patients; mean RNFL thickness was 88.5 μm for individuals with multiple sclerosis compared with a reported normal value of 97 μm (P < 0.001). Eyes with a history of optic neuritis had more thinning compared with those without optic neuritis (83.0 μm versus 90.5 μm, respectively, P = 0.02). No significant differences were observed in macular thickness measurements between eyes with and without optic neuritis, nor were macular thickness measurements significantly different from normal values. As a function of multiple sclerosis duration and controlling for age, RNFL thickness was decreased in patients with a duration of multiple sclerosis greater than five years compared with those with a duration less than or equal to one year (P = 0.008). Conclusions: Patients with a history of multiple sclerosis had RNFL thinning that was detectable on SDOCT. Decreasing RNFL thickness in eyes with optic neuritis was found, and the odds of having optic neuritis were increased significantly with decreasing RNFL thickness. Average RNFL thinning with increasing duration of disease was an excellent predictor of a reported history of optic neuritis. SDOCT retinal imaging may represent a high-resolution, objective, noninvasive, and easily quantifiable in vivo biomarker of the presence of optic neuritis and severity of multiple sclerosis.


Retina-the Journal of Retinal and Vitreous Diseases | 2014

A comparison of same setting versus delayed vitrectomy in the management of retained lens fragments after cataract surgery.

Anton Orlin; George Parlitsis; Ya Lin Chiu; Donald J D'Amico; Robison Vernon Paul Chan; Szilard Kiss

Purpose: Intravitreal retained lens fragments are a rare but potentially serious complication of phacoemulsification. The purpose of this study was to compare same setting (“no wait”) vitrectomy with delayed surgery in the management of retained lens fragments in a single academic setting. Methods: This study is a retrospective nonrandomized study of all patients undergoing pars plana vitrectomy for retained lens fragments after cataract surgery from 2007 to 2012. Outcomes included visual acuity and the development of various complications such as retinal detachment, elevated intraocular pressure >30 mmHg, and cystoid macular edema. Multivariate analysis was performed to adjust for potentially confounding variables such as age and preoperative visual acuity. Results: Twenty-eight consecutive eyes (13 same setting, 15 delayed setting) were included in the analysis. Patients in the same setting group were older than in the delayed group (81.00 vs. 72.87 years, P = 0.053). No other preoperative differences existed between the groups (axial length, preoperative vision, and intraocular pressure). The mean time to pars plana vitrectomy in the delayed group was 26.6 days (range, 1–91 days). The mean follow-up time was 363 days (same setting) and 643 days (delayed). At the most recent follow-up, no significant difference existed in mean vision between the same setting (logMAR, 0.42) and the delayed group (logMAR, 0.57) (P = 0.132). Multivariate analysis showed no difference in final vision when adjusting for age and preoperative vision. Although there was a trend for eyes in the same setting group to obtain good vision (≥20/40) faster, a higher percentage of eyes in the delayed group obtained good vision at the most recent follow-up (66.7 vs. 23.1%, P = 0.02). More eyes in the delayed group had an intraocular pressure >30 at any point (P = 0.055). There was no significant difference between the groups in any other complications such as retinal detachment, choroidal detachment, and cystoid macular edema during the follow-up. Conclusion: In this cohort, same setting pars plana vitrectomy offers no significant visual acuity advantage over delayed pars plana vitrectomy in patients with retained lens fragments. Fewer eyes in the same setting group “ever” had an intraocular pressure ≥30 during follow-up, whereas no other complication differences were seen between the groups.


Journal of Aapos | 2015

Resolution of foveal schisis in X-linked retinoschisis in the setting of retinal detachment.

Mrinali P. Gupta; George Parlitsis; Stephen H. Tsang; R.V. Paul Chan

Patients who have undergone vitrectomy for complications of X-linkedretinoschisis (XLRS) have demonstrated an improvement in foveal schisis after pars plana vitrectomy. We report the case of a 10-year-old boy with XLRS and bilateral foveal schisis in whom macula-involving retinal detachment in one eye was associated with a resolution of foveal schisis in that eye. This case provides additional support for a role of vitreoretinal traction in the pathogenesis of foveal schisis in XLRS.


Neurology | 2014

Infection of the optic apparatus and hypothalamus by Mycobacterium haemophilum

Alexander E. Merkler; George Parlitsis; Sarju Patel; Cristiano Oliveira; Ehud Lavi; Audrey N. Schuetz; Alison May; Dara Bier; Sara Simpson; Szilard Kiss; Marc Dinkin

Mycobacterium haemophilum is a nontuberculous mycobacterium that primarily manifests as cutaneous ulcerations in immunocompromised adults and cervical lymphadenitis in immunocompetent children.1 We present a case of M haemophilum infection of the optic chiasm, tract, and hypothalamus in a patient with AIDS.


Experimental Eye Research | 2011

Peripapillary choroidal thickness in glaucoma measured with optical coherence tomography.

Joshua R. Ehrlich; Jeffrey R. Peterson; George Parlitsis; Kristine Y. Kay; Szilard Kiss; Nathan M. Radcliffe


Investigative Ophthalmology & Visual Science | 2013

Comparison of ultra wide-field fluorescein angiography using the Optos® P200Tx and Heidelberg Spectralis® the non-contact wide-angle lens

George Parlitsis; Matthew T. Witmer; Sarju Patel; Szilard Kiss


Investigative Ophthalmology & Visual Science | 2012

Resident Phacoemulsification Using Two Distinct Surgical Techniques

George Parlitsis; Syed A. Hussnain; Ryan St Clair; Edward C. Lai; Jessica Ciralsky


Investigative Ophthalmology & Visual Science | 2009

Vasoproliferative Tumor of the Retina in Association with Scleral Buckle for Retinal Detachment

George Parlitsis; S. M. Warden; Donald J D'Amico

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