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Dive into the research topics where Steven L. Williams is active.

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Featured researches published by Steven L. Williams.


Survey of Ophthalmology | 2009

Telemedicine for Retinopathy of Prematurity Diagnosis: Evaluation and Challenges

G. M. Richter; Steven L. Williams; Justin Starren; John T. Flynn; Michael F. Chiang

Retinopathy of prematurity (ROP) is a vasoproliferative disorder affecting low birth weight infants. Although timely diagnosis and treatment can significantly reduce the risk of severe complications, ROP remains a leading cause of childhood blindness worldwide. Limitations of current disease management strategies include extensive travel and logistical coordination requirements for ophthalmologists and neonatologists, decreasing availability of adequately trained ophthalmologists at the point of care, variability in how retinal findings are diagnosed and documented, and a growing need for ROP care worldwide. Store-and-forward telemedicine is an emerging technology by which medical data are captured for subsequent interpretation by a remote expert. This has potential to improve accessibility, quality, and cost of ROP management. In this article, we summarize the current evaluation data on applications of telemedicine for ROP, particularly involving the diagnostic accuracy and reliability of remote image interpretation by experts. We also address challenges such as the cost-effectiveness of telemedicine, and highlight potential barriers to implementation of these systems. Understanding these principles is essential to determine future directions in research and development of telemedicine systems for ROP, as well as for other ophthalmic diseases.


Retina-the Journal of Retinal and Vitreous Diseases | 2010

Accuracy of retinopathy of prematurity diagnosis by retinal fellows.

R.V. Paul Chan; Steven L. Williams; Yoshihiro Yonekawa; David J. Weissgold; Thomas C. Lee; Michael F. Chiang

Purpose:The purpose of this study was to measure the accuracy of retinopathy of prematurity (ROP) diagnosis by retinal fellows. Methods:An atlas of 804 retinal images was captured from 248 eyes of 67 premature infants with a wide-angle camera (RetCam-II, Clarity Medical Systems, Pleasanton, CA). Images were uploaded to a study Web site, from which an expert pediatric retinal specialist and 7 retinal fellows independently provided a diagnosis (no ROP, mild ROP, type 2 ROP, or treatment-requiring ROP) for each eye. The sensitivity and specificity of each retinal fellow were calculated and subsequently compared with a reference standard of diagnosis by an expert pediatric retinal specialist. Results:For detection of type 2 or worse ROP by fellows, mean (range) sensitivity was 0.751 (0.512-0.953), and specificity was 0.841 (0.707-0.976). For detection of treatment-requiring ROP, mean (range) sensitivity was 0.914 (0.667-1.000), and specificity was 0.871 (0.678-0.987). Conclusion:In general, fellows showed high accuracy for detecting ROP. However, 3 of 7 fellows achieved <80% sensitivity for diagnosis of type 2 or worse ROP, and 2 of 7 achieved <90% sensitivity for diagnosis of treatment-requiring ROP. This could lead to undermanagement and undertreatment of clinically significant disease and raises potential concerns about the quality of ROP screening examinations performed by less-experienced examiners.


British Journal of Ophthalmology | 2010

Telemedical diagnosis of retinopathy of prematurity: accuracy of expert versus non-expert graders

Steven L. Williams; Lu Wang; Steven A. Kane; Thomas C. Lee; David J. Weissgold; Audina M. Berrocal; Daniel Rabinowitz; Justin Starren; John T. Flynn; Michael F. Chiang

Background/aims To assess accuracy of telemedical retinopathy of prematurity (ROP) diagnosis by trained non-expert graders compared with expert graders. Methods Eye examinations (n=248) from 67 consecutive infants were captured using wide-angle retinal photography (RetCam-II, Clarity Medical Systems, Pleasanton, California, USA). Non-expert graders attended two 1-h training sessions on image-based ROP diagnosis. Using a web-based telemedicine system, 14 non-expert and three expert graders provided a diagnosis for each eye: no ROP, mild ROP, type 2 pre-threshold ROP or treatment-requiring ROP. All diagnoses were compared with a reference standard of dilated indirect ophthalmoscopy by an experienced paediatric ophthalmologist. Results For detection of type 2 or worse ROP, the mean (range) sensitivities and specificities were 0.95 (0.94–0.97) and 0.93 (0.91–0.96) for experts, 0.87 (0.71–0.97) and 0.73 (0.39–0.95) for resident non-experts, and 0.73 (0.41–0.88) and 0.91 (0.84–0.96) for student non-experts, respectively. For detection of treatment-requiring ROP, the mean (range) sensitivities and specificities were 1.00 (1.00–1.00) and 0.93 (0.88–0.96) for experts, 0.88 (0.50–1.00) and 0.84 (0.71–0.98) for resident non-experts, and 0.82 (0.42–1.00) and 0.92 (0.83–0.97) for student non-experts, respectively. Conclusions Mean sensitivity and specificity of trained non-experts were lower than that of experts, although several non-experts had high accuracy. Development of methods for training non-expert graders may help support telemedical ROP evaluation.


Journal of Aapos | 2011

Accuracy of retinopathy of prematurity image-based diagnosis by pediatric ophthalmology fellows: Implications for training

Jane S. Myung; Robison Vernon Paul Chan; Michael J. Espiritu; Steven L. Williams; David B. Granet; Thomas C. Lee; David J. Weissgold; Michael F. Chiang

PURPOSE To measure the accuracy of image-based retinopathy of prematurity (ROP) diagnosis by pediatric ophthalmology fellows. METHODS This was a comparative case series of expert versus nonexpert clinicians in image-based ROP diagnosis. An atlas of 804 retinal images was captured from 248 eyes of 67 premature infants with a wide-angle camera (RetCam-II, Clarity Medical Systems, Pleasanton, CA). Images were uploaded to a study website from which an expert pediatric retinal specialist and five pediatric ophthalmology fellows independently provided a diagnosis (no ROP, mild ROP, type 2 ROP, or treatment-requiring ROP) for each eye. Two different retinal specialists experienced in ROP examination served as additional controls. Primary outcome measures were sensitivity and specificity of image-based ROP diagnosis by fellows compared to a reference standard of image-based interpretation by the expert pediatric retinal specialist. Secondary outcome measure was intraphysician reliability. RESULTS For detection of mild or worse ROP, the mean (range) sensitivity among the five fellows was 0.850 (0.670-0.962) and specificity was 0.919 (0.832-0.964). For detection of type 2 or worse ROP by fellows, mean (range) sensitivity was 0.527 (0.356-0.709) and specificity was 0.938 (0.777-1.000). For detection of treatment-requiring ROP, mean (range) sensitivity was 0.515 (0.267-0.765) and specificity was 0.949 (0.805-1.00). CONCLUSIONS Pediatric ophthalmology fellows in this study demonstrated high diagnostic specificity in image-based ROP diagnosis; however, sensitivity was lower, particularly for clinically significant disease.


British Journal of Ophthalmology | 2015

Spectral domain optical coherence tomography findings in eyes with acute ischaemic retinal whitening

Patrick A. Coady; Emmett T. Cunningham; Robin Vora; H. Richard McDonald; Robert N. Johnson; J. Michael Jumper; Arthur D. Fu; Sara J. Haug; Steven L. Williams; Brandon J. Lujan

Acute retinal ischaemia presents in various forms depending on the type and location of the associated vascular occlusion. Cotton wool spots have been considered one manifestation of ischaemia and represent swelling in the nerve fibre layer. However, clinical retinal whitening also occurs in areas not affected by cotton wool spots, and has distinguishing spectral domain optical coherence tomography (SD-OCT) features. We present SD-OCT findings of hyper-reflectivity and thickening in four eyes with representative retinal arterial or retinal venous occlusions, specifically branch retinal artery occlusion, central retinal vein occlusion, Purtscher-like retinopathy and ophthalmic artery occlusion. The spectrum of retinal ischaemia from various causes was found to manifest in inner nuclear layer hyper-reflectivity and thickening on SD-OCT. En Face OCT imaging further characterises the topographical distribution of ischaemia, and reveals patterns which provide insight into the pathological processes involved.


American Journal of Ophthalmology | 2016

Predictors of Response to Intravitreal Anti-Vascular Endothelial Growth Factor Treatment of Age-Related Macular Degeneration.

Anjali R. Shah; Steven L. Williams; Caroline R. Baumal; Bernard Rosner; Jay S. Duker; Johanna M. Seddon

PURPOSE To identify factors that influence visual and anatomic response to treatment with intravitreal anti-vascular endothelial growth factor (VEGF) for neovascular age-related macular degeneration (AMD). DESIGN Observational cohort study. METHODS Seventy-two patients were included in this study. Best-corrected Snellen visual acuity (VA) and central foveal thickness measured on optical coherence tomography (OCT) at time of treatment and post-treatment follow-up visits were recorded. Associations between demographic, behavioral, and genetic risk factors and the 2 outcomes were analyzed using mixed-effects linear regression models. Two loci in complement factor H (CFH) were included in a risk score to determine the association between CFH risk and improvement in VA and central foveal thickness. RESULTS There was a small improvement in VA following anti-VEGF treatment (mean: 3.7 ± 3.0 letters), which was not statistically significant. Significant improvement in VA was observed for the nonrisk CFH Y402H genotype (P < .001) and for a low CFH risk score (P = .019). Regarding the outcome of change in central foveal thickness, improvement was noted in all genotype groups, but reduction after treatment was significantly higher in the low CFH risk score group (P = .033). A significant improvement in mean VA was seen among smokers (P < .001), but this relationship was not observed for central foveal thickness. CONCLUSION After anti-VEGF therapy, significant improvement in VA was observed for low-risk CFH genotypes and subjects with a low risk score. There was a statistically significant reduction in central foveal thickness overall, and subjects with a low CFH risk score improved more than the high-risk group.


American Journal of Ophthalmology | 2009

Influence of postoperative lens status on intraocular pressure in proliferative vitreoretinopathy.

Joseph J. Tseng; William M. Schiff; Gaetano R. Barile; O'Neil Biscette; Steven L. Williams; Osman Çekiç; Elona Dhrami-Gavazi; Stanley Chang

PURPOSE To determine the influence of lens status on postoperative intraocular pressure (IOP) in eyes undergoing vitrectomy for repair of recurrent retinal detachment (RD) resulting from proliferative vitreoretinopathy (PVR). DESIGN Retrospective, consecutive, nonrandomized, single-center series. METHODS One hundred and forty-five eyes with recurrent RD resulting from PVR were reviewed retrospectively. In all, 99 eyes underwent relaxing retinotomy at the time of surgery (68.4%). Perfluorocarbon gas (n = 60) or silicone oil (n = 85) were used as postoperative tamponades. For analysis, eyes were subdivided first based on tamponade and retinotomy status. The resultant groups then were divided further by lens status into 2 groups: aphakic eyes (aphakic group) and phakic and pseudophakic eyes (nonaphakic group). RESULTS Surgical reattachment was achieved in all eyes except one. Eyes receiving both silicone oil and relaxing retinotomy had the worst baseline characteristics compared with those receiving other interventions. In this subset of eyes, a significantly lower proportion of hypotony was found in those eyes that were aphakic after surgery when compared with those eyes that were nonaphakic (P = .037). CONCLUSIONS Surgical management of PVR often results in ultimate retinal reattachment. In eyes receiving both relaxing retinotomy and silicone oil, higher IOPs and a lower proportion of hypotony are found where a native lens or intraocular implant is absent. Removal of the lens or intraocular implant may be considered for those eyes at greatest risk of hypotony.


Retinal Cases & Brief Reports | 2014

Paraneoplastic vitelliform retinopathy in a patient with treated choroidal melanoma.

Steven L. Williams; H. Richard McDonald; J. Michael Jumper; Arthur D. Fu; Brandon J. Lujan; Emmett T. Cunningham; Robert N. Johnson

PURPOSE To describe a peculiar case of paraneoplastic vitelliform maculopathy/retinopathy in a patient with treated choroidal melanoma. METHODS A case report of a 58-year-old woman with a history of treated choroidal melanoma 16 years before developing visual changes in the setting of metastatic choroidal melanoma. RESULTS We demonstrate bilateral, multifocal vitelliform subretinal lesions and focal, neurosensory retinal detachment associated with metastatic melanoma. CONCLUSION Paraneoplastic vitelliform maculopathy/retinopathy should be considered in patients with or without a history of melanoma, who have unexplained serous, vitelliform retinal detachments, especially with atypical or absence of leakage on fluorescein angiography.


Investigative Ophthalmology & Visual Science | 2008

Plus disease in retinopathy of prematurity: development of composite images by quantification of expert opinion.

Michael F. Chiang; Rony Gelman; Steven L. Williams; Joo Yeon Lee; Daniel S. Casper; M. Elena Martinez-Perez; John T. Flynn


Journal of Aapos | 2011

Accuracy of retinopathy of prematurity image-based diagnosis by pediatric ophthalmology fellows

Jane S. Myung; Robison Vernon Paul Chan; Michael J. Espiritu; Steven L. Williams; David B. Granet; Thomas C. Lee; David J. Weissgold; Michael F. Chiang

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Thomas C. Lee

Children's Hospital Los Angeles

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Arthur D. Fu

California Pacific Medical Center

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