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Dive into the research topics where George N. Magrath is active.

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Featured researches published by George N. Magrath.


Retina-the Journal of Retinal and Vitreous Diseases | 2017

IMAGE QUALITY AND ARTIFACTS ON OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY: Comparison of Pathologic and Paired Fellow Eyes in 65 Patients With Unilateral Choroidal Melanoma Treated With Plaque Radiotherapy.

Emil Anthony T. Say; Sandor Ferenczy; George N. Magrath; Wasim A. Samara; Chloe T. L. Khoo; Carol L. Shields

Purpose: To study image quality and artifacts seen on optical coherence tomography angiography (OCTA). Methods: Sixty-five consecutive patients with unilateral posterior uveal melanoma treated with plaque radiotherapy had OCTA during follow-up. Optical coherence tomography angiography was performed on both the affected and fellow eye. Signal strength and frequency of image artifacts on en face images were compared between affected and fellow eyes. Results: A total of 130 eyes in 65 patients were analyzed, the mean age at time of OCTA was 55 years (median: 56, range: 12–81 years), and 39 (39/65, 60%) were female. Majority of tumors were located in the choroid (62/65, 95%) and extramacular (55/65, 85%). The mean distance to the foveola was 4 mm (median: 3, range: 0–18 mm) and optic nerve was 4 mm (median: 4, range: 0–16 mm). Optical coherence tomography angiography was performed at a mean 46 months after plaque radiotherapy. Most patients had a history of radiation maculopathy or papillopathy in the treated eye at the time of OCTA (46/65, 71%). Overall, 95 eyes (95/130, 73%) had at least one significant artifact on OCTA. The most common major artifacts were loss of focus (71/130, 55%), broad (>5 pixels width and >4 lines) blink lines (48/130, 37%), motion artifact (34/130, 26%), specular dot (33/130, 25%), and edge duplication (10/130, 8%). Statistically, eyes treated with plaque radiotherapy (affected vs. fellow eye) were more likely to have at least one major OCTA artifact (92 vs. 54%, P < 0.001) and, specifically, loss of focus was more frequent (78 vs. 31%, P < 0.001). Multivariate analysis found decreased visual acuity significantly associated with higher incidence of broad blink lines (P = 0.0166) and loss of signal (P < 0.0001), whereas male sex was associated with increased loss of signal (P = 0.0015), and distance to the foveola was related to edge duplication (P = 0.0119). Conclusion: Image artifacts on OCTA are commonly encountered and appear to be more frequent in eyes with pathology and poor visual acuity. Recognition of these artifacts might help improve image interpretation and decision making.


Retina-the Journal of Retinal and Vitreous Diseases | 2017

VARIABILITY IN FOVEAL AVASCULAR ZONE AND CAPILLARY DENSITY USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY MACHINES IN HEALTHY EYES.

George N. Magrath; Emil Anthony T. Say; Kareem Sioufi; Sandor Ferenczy; Wasim A. Samara; Carol L. Shields

Purpose: To evaluate the variability in foveal avascular zone (FAZ) and capillary density measurements on optical coherence tomography angiography using Optovue RTVue XR Avanti (OA) (Optovue) and Zeiss Cirrus HD-OCT 5000 (ZC) (Carl Zeiss Meditec). Methods: In this prospective, comparative case series, parafoveal (3 × 3 mm) optical coherence tomography angiography scans were obtained on healthy volunteers using both the Avanti and Cirrus. The FAZ area and capillary density at the level of both the superficial and deep capillary plexus were measured automatically using the built-in ReVue software (Optovue) with the Avanti as well as manually using ImageJ (National Institutes of Health) with both machines. Results: There were 50 eyes in 25 healthy volunteers included in the analysis. Mean subject age was 33 years and there were 14 women (56%). On optical coherence tomography, mean central macular thickness was significantly greater on OA (259.1 &mgr;m) than ZC (257.6 &mgr;m, P = 0.0228). On optical coherence tomography angiography, mean superficial and deep plexus FAZ measured 0.2855 mm2 and 0.3465 mm2 on Avanti automated (A-A), 0.2739 mm2 and 0.3637 mm2 on Avanti manual (A-M), and 0.2657 mm2 and 0.3993 mm2 on Cirrus manual (C-M), respectively. There were no statistically significant differences in superficial plexus FAZ measurements between the A-A and A-M (P = 0.4019) or A-A and C-M (P = 0.1336). The A-M measured significantly larger than C-M (P = 0.0396). Deep plexus FAZ measurements were similar on A-A and A-M (P = 0.6299), but both were significantly less compared with C-M (P < 0.0001 for A-A vs. C-M, P = 0.0184 for A-M vs. C-M). Mean superficial and deep plexus capillary densities were 53.6% and 59.3% on A-A, 48.1% and 47.7% on A-M, and 52.5% and 48.1% on C-M, respectively. Superficial plexus capillary density measurements were statistically similar on A-A and C-M (P = 0.0623), but both were significantly higher than A-M (P < 0.0001 for A-A vs. A-M, P < 0.0001 for A-M vs. C-M). However, deep plexus capillary density measurements on A-A were significantly higher than A-M (P < 0.0001) and C-M (P < 0.0001), but A-M and C-M measurements were similar (P = 0.5986). There was no significant difference in all parameters measured in both eyes of one subject using any of the three measuring techniques. Conclusion: While measurements taken with the same machine and technique are consistent and reliable between fellow eyes, significant variability exists in FAZ and capillary density measurements among different machines and techniques. Comparison of measurements across machines and techniques should be considered with caution.


Retina-the Journal of Retinal and Vitreous Diseases | 2016

PARAFOVEAL CAPILLARY DENSITY AFTER PLAQUE RADIOTHERAPY FOR CHOROIDAL MELANOMA: Analysis of Eyes Without Radiation Maculopathy.

Emil Anthony T. Say; Wasim A. Samara; Chloe T. L. Khoo; George N. Magrath; Priya Sharma; Sandor Ferenczy; Carol L. Shields

Purpose: To study the parafoveal capillary density using optical coherence tomography angiography (OCTA) in eyes treated with plaque radiotherapy. Research Design: Retrospective comparative case series. Participants: Ten patients treated with plaque radiotherapy for choroidal melanoma without evident radiation maculopathy on ophthalmoscopy or optical coherence tomography were imaged with OCTA. Main Outcome Measure: Comparison of the parafoveal capillary density in the superficial and deep capillary plexuses in the irradiated versus fellow nonirradiated eye. Results: Overall, mean patient age was 55 years (median: 57, range: 45–65 years), and majority were white (9/10, 90%) and female (9/10, 90%). No patient had diabetes mellitus, and 2 (2/10, 20%) had controlled systemic hypertension. The melanoma was located in the choroid in all patients (10/10, 100%), with 2 (2/10, 20%) in the macular region. The mean largest basal diameter was 11 mm (12, 6–16 mm), and mean thickness was 5 mm (5, 2–10 mm). Mean radiation dose to the tumor apex was 72 Gy (median: 70 Gy, range: 70–85 Gy). Mean foveolar radiation dose was 53 Gy (median: 35 Gy, range: 14–110 Gy). Mean follow-up duration after plaque radiotherapy was 17 months (median: 16 months, range: 5–39 months). There was no ophthalmoscopic evidence of radiation maculopathy throughout the follow-up in every case. Optical coherence tomography demonstrated normal foveal contour without edema or subretinal fluid in every case. On OCTA, there was no significant difference in signal strength (P = 0.1151), central macular thickness (P = 0.9316), and foveal avascular zone area in the superficial (P = 0.1595), and deep (P = 0.1534) capillary plexuses between the irradiated versus fellow eyes. However, there was a statistically significant decrease in capillary density in the parafoveal superficial (P = 0.0005) and deep (P = 0.0067) plexuses in the irradiated eye. In addition, mean logMAR visual acuity was 0.2 (0.1, 0.0–0.5) (Snellen equivalent 20/32) in the irradiated eye and 0.0 (0.0, range: 0.0–0.1) (Snellen equivalent 20/20) in the fellow eye (P = 0.0252). Conclusion: Optical coherence tomography angiography allows qualitative and quantitative analysis of parafoveal capillary density. After plaque radiotherapy for choroidal melanoma, in eyes with normal macular features on ophthalmoscopy and optical coherence tomography, there is a statistically significant decrease in parafoveal capillary density and logMAR visual acuity in irradiated eyes compared with fellow eyes. These subclinical ischemic findings represent the commencement of radiation maculopathy.


Orbit | 2015

Esophageal Adenocarcinoma and Urothelial Carcinoma Orbital Metastases Masquerading as Infection

George N. Magrath; Charles Medlock Proctor; Wade A. Reardon; Krishna G. Patel; Eric J. Lentsch; Andrew S. Eiseman

Abstract Orbital metastases can masquerade as other orbital processes. We present two cases of orbital metastases, the first being the first reported adenocarcinoma of the esophagus presenting as an orbital metastasis prior to the primary being known, and the other as the first urothelial carcinoma to present as orbital cellulitis. The first patient presented with left upper eyelid pain. CT scan identified a superolateral subperiosteal fluid collection without concomitant sinus disease, which was drained in the operating room. Two weeks later repeat CT scan showed recurrent orbital subperiosteal fluid. It was drained and a biopsy showed necrotic adenocarcinoma. The second case presented with a painless right proptosis, decreased vision, and globally decreased ocular motility 3 days after bladder resection for urothelial carcinoma. CT scan demonstrated pan sinusitis with a soft tissue mass in the apex of the right orbit with extension through the superior orbital fissure. After no improvement on antibiotics endoscopic drainage was performed. Pathology revealed metastatic urothelial carcinoma within the orbital fat.


Ocular Oncology and Pathology | 2016

Dissecting Aortic Aneurysm 55 Years after Diagnosis of Iris Flocculi

Jerry A. Shields; George N. Magrath; Carol L. Shields; Richard Mackool; Ralph C. Eagle; Hans E. Grossniklaus

Purpose: The aim of this study is to report the clinical features, imaging studies, surgical removal, and pathology of congenital iris flocculi in a patient who developed a life-threatening dissecting aortic aneurysm after 55 years of follow-up. Methods: Documentation with iris photography was performed from age 18 to 55 years, at which time anterior segment optical coherence tomography (OCT) was performed. At the time of subsequent cataract surgery, the iris flocculi were removed in each eye and submitted for light and electron microscopy. Results: The size and shape of the iris flocculi waxed and waned over the years but caused no visual disturbance. Anterior segment OCT demonstrated clear, round cysts with thin lining and no solid component. At the age of 55, congestive heart failure from a dissecting aortic aneurysm was discovered and surgically repaired. Subsequent bilateral cataract surgery and cyst removal were performed, and the iris flocculi were studied with light and electron microscopy. Conclusions: Congenital iris flocculi cause little, if any, visual impairment in most cases. However, they are occasionally associated with dissecting aortic aneurysm due to a shared mutation in smooth muscle that affects both the iris and the aorta. Patients with iris flocculi should be monitored periodically for aortic abnormalities.


Ocular Immunology and Inflammation | 2010

Cystoid macular edema secondary to fluconazole toxicity

George N. Magrath; Jose S. Pulido; Javier Montero; Craig Mason; John W. Wilson

Fluconazole is an antifungal commonly used to treat Coccidioides immitis, but this medication has a number of side effects including fatigue, rash, headache, dizziness, nausea, vomiting, diarrhea, and elevated liver enzymes. We are unaware of any cases of retinal toxicity related to fluconazole. In this case we present a 76 year old woman with longstanding Coccidioides treated with high dose fluconazole. She becomes symptomatic with fluconazole toxicity and subsequently develops bilateral cystoid macular edema. As her dose of fluconazole is decreased and she is transitioned to voriconazole the edema resolves and her visual acuity improves. This patient’s clinical course illustrates retinal toxicity may present with high and prolonged doses of fluconazole.


Journal of Pediatric Ophthalmology & Strabismus | 2017

Detection of Minimally Visible Recurrent Retinoblastoma by Hand-held Spectral-Domain Optical Coherence Tomography

Maria E Gonzalez-Montpetit; Wasim A. Samara; George N. Magrath; Carol L. Shields

A 2-month-old male infant with bilateral familial retinoblastoma was treated with intravenous chemotherapy and focal adjuvant therapy. At 5 months of follow-up, fundus examination and ultrasonography disclosed no recurrence; however, hand-held spectral-domain optical coherence tomography (SD-OCT) demonstrated subclinical recurrence within a previous regression scar. Subsequent treatment led to flat scar. Hand-held SD-OCT can be a useful tool for detection of subclinical recurrent retinoblastoma. [J Pediatr Ophthalmol Strabismus. 2017;54:e6-e8.].


American Journal of Ophthalmology Case Reports | 2018

Iris melanoma presenting as childhood glaucoma

Briana C. Gapsis; Nichelle A. Warren; Matthew J. Nutaitis; Leah A. Bonaparte; Samuel Lewis Cooper; M Ashenafi; Hans E. Grossniklaus; George N. Magrath

Purpose To describe the natural history and management of a rare case of iris melanoma in a pediatric patient. Observations A Caucasian female presented with left pupillary abnormalities at age 7, progressive iris changes at age 9, and markedly elevated intraocular pressure with advanced optic nerve cupping at 11 years of age. She was found to have a pigmented lesion overlying her iris and invading her angle. Trans-corneal fine needle aspirate biopsy demonstrated malignant melanoma of the iris. The patient subsequently underwent Iodine-125 plaque brachytherapy for the tumor. Conclusions and Importance: Early identification and treatment of iris melanoma may be associated with decreased risk of local progression and metastatic disease. Treatment of glaucoma in conjunction with uveal melanoma is complicated by tumor specific considerations, including treatment of the tumor and prevention of metastasis.


Pediatric Neurology | 2013

Morning glory optic disc anomaly.

George N. Magrath; Edward W. Cheeseman; Robert A. Sarrica


/data/revues/00223476/unassign/S0022347613001133/ | 2013

A Rapidly Expanding Orbital Lesion

George N. Magrath; Edward W. Cheeseman; Andrew S. Eiseman; Michael J. Caplan

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Carol L. Shields

Thomas Jefferson University

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Wasim A. Samara

Thomas Jefferson University

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Charles Medlock Proctor

Medical University of South Carolina

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Sandor Ferenczy

Thomas Jefferson University

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Andrew S. Eiseman

Medical University of South Carolina

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Chloe T. L. Khoo

Thomas Jefferson University

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Edward W. Cheeseman

Medical University of South Carolina

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Jerry A. Shields

Thomas Jefferson University

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