Helen K Li

Weill Cornell Medical College, New York City, New York, United States

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Publications (21)67.22 Total impact

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    ABSTRACT: : During evaluation for monocular visual loss, a 48-year-old woman was found to have a posttraumatic paraophthalmic internal carotid artery (ICA) pseudoaneurysm. She underwent reconstruction of the ophthalmic segment of the right ICA with a Pipeline embolization device but her vision did not return.
    Journal of neuro-ophthalmology: the official journal of the North American Neuro-Ophthalmology Society 10/2013; 33(4). DOI:10.1097/WNO.0b013e3182a30427 · 1.81 Impact Factor
  • Baoxin Li, Helen K Li
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    ABSTRACT: Diabetic retinopathy (DR) is a vision-threatening complication of diabetes. Timely diagnosis and intervention are essential for treatment that reduces the risk of vision loss. A good color retinal (fundus) photograph can be used as a surrogate for face-to-face evaluation of DR. The use of computers to assist or fully automate DR evaluation from retinal images has been studied for many years. Early work showed promising results for algorithms in detecting and classifying DR pathology. Newer techniques include those that adapt machine learning technology to DR image analysis. Challenges remain, however, that must be overcome before fully automatic DR detection and analysis systems become practical clinical tools.
    Current Diabetes Reports 05/2013; 13(4). DOI:10.1007/s11892-013-0393-9 · 3.38 Impact Factor
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    ABSTRACT: Diabetic retinopathy (DR) is a vision-threatening complication that affects people suffering from diabetes. Diagnosis of DR during early stages can significantly reduce the risk of severe vision loss. The process of DR severity grading is prone to human error and it also depends on the expertise of the ophthalmologist. As a result, many researchers have started exploring automated detection and evaluation of diabetic retinal lesions. Unfortunately, to date there is no automated system that can perform DR lesion detection with the accuracy that is comparable to a human expert. In this poster, we present a novel way of employing content-based image retrieval for providing a clinician with instant reference to archival and standardized DR images that are used for assisting the ophthalmologist with the diagnosis of a given DR image. The focus of the poster is on retrieving DR images with two significant DR clinical findings, namely, microaneurysm (MA) and neovascularization (NV). We propose a multi-class multiple-instance DR image retrieval framework that makes use of a modified color correlogram (CC) and statistics of steerable Gaussian filter (SGF) responses. Experiments using real DR images with comparisons to other prior-art methods demonstrate the improved performance of the proposed approach.
    Proceedings of the ACM Conference on Bioinformatics, Computational Biology and Biomedicine; 10/2012
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    ABSTRACT: All people with diabetes have the risk of developing diabetic retinopathy (DR), a vision-threatening complication. Early detection and timely treatment can reduce the occurrence of blindness due to DR. Computer-aided diagnosis has the potential benefit of improving the accuracy and speed in DR detection. This study is concerned with automatic classification of images with microaneurysm (MA) and neovascularization (NV), two important DR clinical findings. Together with normal images, this presents a 3-class classification problem. We propose a modified color auto-correlogram feature (AutoCC) with low dimensionality that is spectrally tuned towards DR images. Recognizing the fact that the images with or without MA or NV are generally different only in small, localized regions, we propose to employ a multi-class, multiple-instance learning framework for performing the classification task using the proposed feature. Extensive experiments including comparison with a few state-of-art image classification approaches have been performed and the results suggest that the proposed approach is promising as it outperforms other methods by a large margin.
    Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 08/2012; 2012:1462-5. DOI:10.1109/EMBC.2012.6346216
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    ABSTRACT: To compare agreement between mosaicked and seven field photographs for classification of the diabetic retinopathy (DR) severity. Mosaic digital (MosD) images were compared with seven field stereo film (7FF) and stereo digital (7FD) photographs from a 152-eye cohort with full-spectrum Early Treatment of Diabetic Retinopathy severity levels for agreement on severity level, DR presence with ascending severity thresholds, DR index lesion presence, and classification repeatability. There was a substantial agreement classifying the Early Treatment Diabetic Retinopathy Study DR severity level between MosD and 7FF (kunweighted = 0.59, klinear weighted = 0.83), MosD and 7FD (κ = 0.62, κ weighted = 0.86), and 7FD and 7FF (κ = 0.62, κ weighted = 0.86) images. Marginal homogeneity analyses found no significant difference between MosD and 7FF (P = 0.44, Bhapkar's test). Kappa between MosD and 7FF ranged from 0.75 to 0.91 for the presence or absence of DR at 8 ascending severity thresholds. Repeatability among readers using MosD images was similar to repeatability among those using 7FF or 7FD. Repeatability among readers using MosD and 7FF images at various severity thresholds was similar. Kappa between MosD and 7FF grading for identifying DR lesions ranged from 0.61 to 1.00. Mosaic images are generally comparable with standard seven-field photographs for classifying DR severity.
    Retina (Philadelphia, Pa.) 04/2011; 31(8):1553-63. DOI:10.1097/IAE.0b013e3182084273 · 3.18 Impact Factor
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    ABSTRACT: To evaluate digital photography parameters affecting comparability with the Early Treatment Diabetic Retinopathy Study (ETDRS) film protocol for diabetic retinopathy (DR) severity grading. ETDRS protocol photographs and four variations of digital images (uncompressed stereoscopic, compressed stereoscopic, uncompressed monoscopic, and uncompressed monoscopic wide-angle mosaic) of 152 eyes were independently evaluated by using ETDRS classifications. Digital formats were compared to film and each other for agreement on severity level, DR presence at ascending threshold, presence of the DR index lesion, and repeatability of grading. Study parameters included image resolution sufficient to distinguish small lesions, color balancing of digital images to film, documenting essential ETDRS classification retinal regions, similar magnification, and supplementary green-channel viewing. The κ statistic was substantial or near substantial between all digital formats and film for classifying severity levels (κ = 0.59-0.62; κ(w) [linear weighted] = 0.83-0.87). The distribution of DR levels in all digital formats was not significantly different from that of the film (Bhapkar test, P = 0.09-0.44). The κ among digital formats for severity level was also substantial or near substantial (κ = 0.58-0.76, κ(w) = 0.82-0.92). Differences between digital formats and film for grading severity level, severity threshold, or index lesions were not significant. The repeatability of grading between readers using film and all digital formats was also similar. Digital format variations compared favorably with film for DR classification. Translating film characteristics (resolution, color/contrast) and protocol (magnification, retinal regions) to digital equivalents and augmentation of full color with green-channel viewing most likely contributed to the results.
    Investigative ophthalmology & visual science 02/2011; 52(7):4717-25. DOI:10.1167/iovs.10-6303 · 3.66 Impact Factor
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    ABSTRACT: To assess agreement between evaluations of monoscopic and stereoscopic digital images versus stereo film photographs in diabetic macular edema (DME). A 152-eye group of digital monoscopic macular images (seven-field sets and wide-angle mosaics) were compared with digital stereoscopic images (uncompressed and compressed seven-field sets) and stereo 35-mm film photos (Early Treatment Diabetic Retinopathy Study protocol) for the presence of hard exudates (HE), retinal thickening (RT), clinically significant macular edema (CSME), and RT at the center of the macular (RTCM). Agreement, according to the κ statistic, was almost perfect in identifying HE and RT between all digital formats and stereo film (HE, κ = 0.81-0.87; RT, κ = 0.87-0.92). Distribution in all digital formats was not significantly different from that in film (Bhapkar test: HE, P = 0.20-0.40; RT, P = 0.06-1.0). CSME and RTCM grading differences were either significant or trended toward significance. The readers detected CSME and RTCM in film images more often than in digital formats. In identifying DME features, agreement between evaluations of monoscopic digital formats and film was similar to that between stereo digital formats and film, and the performance of uncompressed images versus film was similar to that of compressed images versus film. Repeatability between readers was similar in evaluations of film and all digital formats. Repeatability in identifying RTCM was lower than that of other DME components in film and all digital formats. Stereoscopic digital formats are equivalent to monoscopic for DME evaluation, but digital photography is not as sensitive as film in detecting CSME and RTCM.
    Investigative ophthalmology & visual science 12/2010; 51(12):6753-61. DOI:10.1167/iovs.10-5504 · 3.66 Impact Factor
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    ABSTRACT: To assess agreement between digital and film photography for research classification of diabetic retinopathy severity. Digital and film photographs from a 152-eye cohort with a full spectrum of Early Treatment Diabetic Retinopathy Study (ETDRS) severity levels were assessed for repeatability of grading within each image medium and for agreement on ETDRS discrete severity levels, ascending severity thresholds, and presence or absence of diabetic retinopathy index lesions, between digital and 35-mm slides (film). Digital photographs were color balanced to match film. There was substantial agreement (κ = 0.61, κ(w) [linear weighted] = 0.87) in classification of ETDRS diabetic retinopathy severity levels between digital images and film. Marginal homogeneity analyses found no significant difference in frequency distributions on the severity scale (P = 0.21, Bhapkar test). The κ results ranged from 0.72 to 0.95 for presence or absence of eight ascending diabetic retinopathy severity thresholds. Repeatability of grading between readers viewing digital images was equal to or better than that obtained with film (pair-wise interreader κ for digital images ranged from 0.47 to 0.57 and for film from 0.43 to 0.57. The κ results for identifying diabetic retinopathy lesions ranged from moderate to almost perfect. Moderate agreement of intraretinal microvascular abnormalities and venous beading between digital images and film accounted for slightly lower concordance for severity thresholds ≥47 and for slightly lower interreader agreement within digital and film images at severity thresholds ≥43 and ≥47. Under controlled circumstances, digital photography can equal the reliability of 35-mm slides for research classification of ETDRS severity level.
    Investigative ophthalmology & visual science 11/2010; 51(11):5846-52. DOI:10.1167/iovs.09-4803 · 3.66 Impact Factor
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    ABSTRACT: To compare research grading of diabetic retinopathy (DR) severity level from compressed digital images versus uncompressed images and film. Compressed (JPEG2000, 37:1) digital images (C) were compared with uncompressed digital (U) and film (F) stereoscopic photographs from a 152-eye cohort with full-spectrum Early Treatment Diabetic Retinopathy Study severity levels for agreement on severity level, DR presence with ascending severity threshold, presence of DR index lesions, and repeatability of grading. Classification of Early Treatment Diabetic Retinopathy Study severity levels from C images agreed substantially with results from F images (κ = 0.60, κ(w) [linear weighted] = 0.86) and uncompressed digital images (κ = 0.76, κ(w) = 0.92). For agreement of uncompressed digital versus F images, κ = 0.62 and κ(w) = 0.86. Distribution of Early Treatment Diabetic Retinopathy Study levels was not significantly different between C and F images (P = 0.09, Bhapkar's test for marginal homogeneity). For presence/absence of DR at 8 ascending severity thresholds, agreement between C and F was "almost perfect" (κ ≥ 0.8). Agreement on severity level between readers with C images was at least as good as that with uncompressed digital image or F. Repeatability of severity threshold grading between readers was similar using C or F images. For identifying individual DR lesions, agreement between C and F ranged from "moderate" to "perfect." Agreement of grading venous beading from C was slightly lower than from F. Full Early Treatment Diabetic Retinopathy Study scale DR severity level grading using C images is comparable to that using U images or film.
    Retina (Philadelphia, Pa.) 10/2010; 30(10):1651-61. DOI:10.1097/IAE.0b013e3181e3790b · 3.18 Impact Factor
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    ABSTRACT: To assess agreement between monoscopic and stereoscopic photography for research classification of the severity of diabetic retinopathy (DR). Monoscopic digital (MD) images were compared with stereo digital (SD) and film (SF) photographs from a 152-eye cohort with full-spectrum Early Treatment Diabetic Retinopathy Study (ETDRS) severity levels for agreement on severity level, DR presence with ascending severity threshold, presence of DR index lesions, and repeatability of grading. There was substantial agreement classifying ETDRS DR severity levels between MD and SF (kappa = 0.65, kappa(w) [linear weighted] = 0.87), MD and SD (kappa = 0.66, kappa(w) = 0.87), and SD and SF (kappa = 0.62, kappa(w) = 0.86) images. Marginal homogeneity analyses found no significant difference between MD and SF images (P = 0.53, Bhapkar test). The kappa agreement between MD and SF ranged from 0.80 to 0.94 for the presence or absence of eight ascending DR severity thresholds. Repeatability between the readers of the MD images was equal to or better than that of the readers of SD or SF images. Severity threshold grading repeatability between readers was similar with the MD and SF images. The kappa agreement between MD and SF for identifying diabetic retinopathy lesions ranged from moderate to almost perfect. The kappa comparisons showed that performance of grading new vessels on the disc in MD images was slightly lower than that with the SF images. Monoscopic photography can equal the reliability of stereo photography for full ETDRS DR severity scale grading.
    Investigative ophthalmology & visual science 06/2010; 51(6):3184-92. DOI:10.1167/iovs.09-4886 · 3.66 Impact Factor
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    ABSTRACT: We report a ciliary body melanoma that apparently arose from a melanocytoma in a 15-year-old black teenager. The eye was enucleated, and metastatic evaluation remained negative at 5 years' follow-up. This unusual case, confirmed histopathologically, reveals that young patients with melanocytoma can have malignant transformation at an early age.
    Journal of AAPOS: the official publication of the American Association for Pediatric Ophthalmology and Strabismus / American Association for Pediatric Ophthalmology and Strabismus 04/2010; 14(2):178-80. DOI:10.1016/j.jaapos.2010.01.007 · 1.14 Impact Factor
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    ABSTRACT: Evaluation of clinical features and natural course of giant choroidal nevi (diameter >or=10 mm). Retrospective observational case series. We included 322 eyes of 322 patients. Clinic-based study of tumor features, tumor outcome, and vision outcome. Kaplan-Meier analysis was used to assess time to transformation into melanoma. Cox proportional hazards regressions evaluated clinical factors predictive of nevus transformation into melanoma and nevus-related decreased vision (defined as <20/20 and unrelated to other eye pathology). Transformation of giant choroidal nevus into melanoma and nevus-related decreased vision. A medical record review of 4100 patients diagnosed with choroidal nevus identified 322 (8%) giant choroidal nevi. Median nevus basal diameter was 11 mm (range, 10-24). Median thickness was 1.9 mm (range, 0-4.4). Related retinal findings included drusen overlying nevus (n = 261 [81%]), subretinal fluid (n = 26 [8%]), orange pigment (n = 4 [1%]), retinal pigment epithelial (RPE) detachment (n = 6 [2%]), hyperplasia (n = 48 [15%]), fibrous metaplasia (n = 48 [15%]), atrophy (n = 63 [20%]), or trough (n = 6 [2%]). Kaplan-Meier analysis estimated transformation into melanoma in 13% at 5 years and 18% at 10 years. Multivariate analyses revealed factors predictive of transformation into melanoma including involvement or close proximity to the foveola (P = 0.017) and acoustic hollowness (P = 0.052). Nevus-related decreased vision was found in 2.2% of eyes at initial visit and 3.7% at final visit (median 41 and mean 61 months follow-up). Factors associated with nevus-related decreased vision at initial visit included subretinal fluid (P = 0.001), involvement or close proximity to foveola (P = 0.005), RPE detachment (P = 0.033), and nevus-related choroidal neovascular membrane (P = 0.044). Factors predictive of nevus-related decreased vision at final visit included involvement or close proximity to the foveola (P = 0.001) and presence of symptoms at the initial visit (P = 0.032). Giant choroidal nevi can clinically resemble choroidal melanoma but show features of chronicity, such as overlying drusen and RPE alterations. Over time, 18% transformed into melanoma, underscoring the importance of life-long surveillance.
    Ophthalmology 12/2009; 117(2):324-33. DOI:10.1016/j.ophtha.2009.07.006 · 6.17 Impact Factor
  • Clinical and Experimental Ophthalmology 01/2009; 36(9):895-7. DOI:10.1111/j.1442-9071.2008.01902.x · 1.95 Impact Factor
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    ABSTRACT: To explore the correlation between optical coherence tomography (OCT) and stereoscopic fundus photographs (FP) for the assessment of retinal thickening (RT) in diabetic macular edema (DME) within a clinical trial. OCT, FP, and best corrected visual acuity (VA) measurements were obtained in both eyes of 263 participants in a trial comparing two photocoagulation techniques for DME. Correlation coefficients (r) were calculated comparing RT measured by OCT, RT estimated from FP, and VA. Principal variables were central subfield retinal thickness (CSRT) obtained from the OCT fast macular map and DME severity assessed by a reading center using a seven-step photographic scale combining the area of thickened retina within 1 disc diameter of the foveal center and thickening at the center. Medians (quartiles) for retinal thickness within the center subfield by OCT at baseline increased from 236 (214, 264) microm in the lowest level of the photographic scale to 517 (455, 598) microm in the highest level (r = 0.67). However, CSRT interquartile ranges were broad and overlapping between FP scale levels, and there were many outliers. Correlations between either modality and VA were weaker (r = 0.57 for CSRT, and r = 0.47 for the FP scale). OCT appeared to be more reproducible and more sensitive to change in RT between baseline and 1 year than was FP. There was a moderate correlation between OCT and FP assessments of RT in patients with DME and slightly less correlation of either measure with VA. OCT and FP provide complementary information but neither is a reliable surrogate for VA.
    Investigative Ophthalmology &amp Visual Science 06/2008; 49(5):1745-52. DOI:10.1167/iovs.07-1257 · 3.66 Impact Factor
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    ABSTRACT: To evaluate optical coherence tomography (OCT) thickness of the macula in people with diabetes but minimal or no retinopathy and to compare these findings with published normative data in the literature from subjects reported to have no retinal disease. Cross-sectional study. In a multicenter community- and university-based practices setting, 97 subjects with diabetes with no or minimal diabetic retinopathy and no central retinal thickening on clinical examination and a center point thickness of 225 microm or less on OCT (Stratus OCT; Carl Zeiss Meditec, Dublin, California, USA) were recruited. Electronic Early Treatment of Diabetic Retinopathy Study best-corrected visual acuity, seven-field stereoscopic color fundus photographs, and Stratus OCT fast macular scan were noted. Main outcome measures were central subfield (CSF) thickness measured on Stratus OCT. On average, CSF thickness was 201 +/- 22 microm. CSF thickness was significantly greater in retinas from men than retinas from women (mean +/- standard deviation, 209 +/- 18 microm vs 194 +/- 23 microm; P < .001). After adjusting for gender, no additional factors were found to be associated significantly with CSF thickness (P > .10). CSF thicknesses on Stratus OCT in people with diabetes and minimal or no retinopathy are similar to thicknesses reported from a normative database of people without diabetes. CSF thickness is greater in men than in women, consistent with many, but not all, previous reports. Studies involving comparisons of retinal thickness with expected norms should consider different mean values for women and men.
    American Journal of Ophthalmology 05/2008; 145(5):894-901. DOI:10.1016/j.ajo.2007.12.025 · 4.02 Impact Factor
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    ABSTRACT: Diabetic retinopathy (DR) has been identified as a leading cause of blindness. One type of lesion, neovascularization (NV), indicates that the disease has entered a vision-threatening phase. Early detection of NV is thus clinically significant. Efforts have been devoted to use computer-aided analyses of digital retina images to detect DR. However, developing reliable NV detection algorithms requires large numbers of digital retinal images to test and refine approaches. Computer simulation of NV offers the potential of developing lesion detection algorithms without the need for large image databases of real pathology. In this paper, we propose a systematic approach to simulating NV. Specifically, we propose two algorithms based on fractal models to simulate the main structure of NV and an adaptive color generation method to assign photorealistic pixel values to the structure. Moreover, we develop an interactive system that provides instant visual feedback to support NV simulation guided by an ophthalmologist. This enables us to combine the low level algorithms with high-level human feedback to simulate realistic lesions. Experiments suggest that our method is able to produce simulated NVs that are indistinguishable from real lesions.
    Advances in Visual Computing, Second International Symposium, ISVC 2006, Lake Tahoe, NV, USA, November 6-8, 2006 Proceedings, Part I; 01/2006
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    ABSTRACT: To describe the course of cytomegalovirus (CMV) retinitis in patients with AIDS in the era of highly active antiretroviral therapy (HAART). Multicenter, prospective, observational study. Two hundred seventy-one patients with AIDS and CMV retinitis. Follow-up every 3 months with medical history, ophthalmologic examination, laboratory testing, and fundus photographs. Photographs were evaluated for relapse of the retinitis (progression) by graders at a centralized reading center. Retinitis progression (movement of the border of a CMV lesion > or =750 microm over a > or =750-microm front or occurrence of a new lesion one-quarter disc area or more in size). The overall rate of retinitis progression was 0.10/person-year (PY); among those with CD4+ T-cell counts of <50/microl, it was 0.58/PY, compared to 0.02/PY among those with CD4+ T-cell counts of > or =200/microl (P<0.0001). In the multivariate analysis, significant risk factors for retinitis progression included a low CD4+ T-cell count, positive CMV load, longer time from AIDS diagnosis, and low Karnofsky score. Compared with the rate of retinitis progression (approximately 3.0/PY) reported in the pre-HAART era, the rate of retinitis progression was reduced among patients in the HAART era, even among those with low CD4+ T-cell counts, who might be expected to behave most like patients from the pre-HAART era. However, these events also occurred among patients with high CD4+ T-cell counts and presumed immune recovery. Continued ophthalmologic follow-up of patients with immune recovery is recommended to detect early retinitis progression.
    Ophthalmology 01/2005; 111(12):2224-31. DOI:10.1016/j.ophtha.2004.05.031 · 6.17 Impact Factor
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    ABSTRACT: To describe the course of cytomegalovirus (CMV) retinitis in patients with AIDS in the era of highly active antiretroviral therapy (HAART). Multicenter, prospective, observational study. Two hundred seventy-one patients with AIDS and CMV retinitis. Follow-up every 3 months with medical history, ophthalmologic examination, laboratory testing, and fundus photographs. Second (contralateral) eye involvement among patients with unilateral disease and retinal detachment (RD). The overall rate of second eye involvement among patients with unilateral CMV retinitis was 0.07 per person-year (PY); among those with CD4+ T-cell counts of <50/microl it was 0.34/PY, compared with 0.02/PY among those with CD4+ T-cell counts of > or =200/microl (P<0.0001). Risk factors for contralateral eye involvement included low CD4+ T-cell count and detectable CMV load. The overall rate of RD was 0.06/PY; among those with CD4+ T-cell counts of <50/microl it was 0.30/PY, compared with 0.02/PY among those with CD4+ T-cell counts of > or =200/microl (P<0.0001). Risk factors for RD included a low CD4+ T-cell count and larger area of CMV retinitis. Compared with the rates reported in the pre-HAART era of second eye involvement (approximately 0.40/PY) and RD (approximately 0.50/PY), the rates of these events were reduced among patients in the HAART era. However, among patients with CD4+ T-cell counts of <50/microl, the rates were more similar to those from the pre-HAART era.
    Ophthalmology 01/2005; 111(12):2232-9. DOI:10.1016/j.ophtha.2004.05.028 · 6.17 Impact Factor
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    ABSTRACT: A cost-effectiveness analysis was conducted to investigate the clinical and economic impact of teleophthalmology in evaluating diabetic retinopathy in prison inmates with type 2 diabetes. Based on a hypothetical teleophthalmology system to evaluate diabetic retinopathy patients with type 2 diabetes in a prison care setting, a Markov decision model was developed with probability and cost data derived primarily from published epidemiological and outcome studies. A 40-year-old African-American man with type 2 diabetes was used as a reference case subject. The number of quality-adjusted life-years (QALYs) gained was used as the clinical outcome, and the cost in U.S. dollars from the year 2003 was used as the economic outcome. Teleophthalmology and nonteleophthalmology strategies were compared using an expected QALYs calculation and two types of sensitivity analyses: probabilistic and traditional n-way sensitivity analyses. The teleophthalmology strategy dominates in the cost-effectiveness analysis for the reference case subject: 16,514/18.73 dollars QALYs for teleophthalmology and 17,590/18.58 dollars QALYs for nonteleophthalmology. Ninety percent of the Monte Carlo simulations showed cost effectiveness (annual cost/QALYs < or = 50,000 dollars) in the teleophthalmology strategy based on an assumed inmate population. Teleophthalmology is the better strategy if the number of diabetic inmates in the prison community is >500. Our cost-effectiveness analysis demonstrates that teleophthalmology holds great promise to reduce the cost of inmate care and reduce blindness caused by diabetic retinopathy in type 2 diabetic patients.
    Diabetes Care 05/2004; 27(5):1095-101. DOI:10.2337/diacare.27.5.1095 · 8.57 Impact Factor
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    ABSTRACT: Six digital fundus cameras were examined to determine degrees of distortion introduced by lenses. Results quantified lens distortion effects on fundus images and demonstrate intrinsic properties in similar camera systems may vary.
    Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 02/2004; 2:1497-500. DOI:10.1109/IEMBS.2004.1403460

Publication Stats

249 Citations
67.22 Total Impact Points

Institutions

  • 2013
    • Weill Cornell Medical College
      New York City, New York, United States
  • 2010–2013
    • University of Texas Health Science Center at Houston
      Houston, Texas, United States
  • 2009–2012
    • Thomas Jefferson University
      • • Department of Ophthalmology
      • • Wills Eye Institute
      Philadelphia, Pennsylvania, United States
  • 2005–2009
    • University of Texas Medical Branch at Galveston
      Galveston, Texas, United States
  • 2008
    • Texas A&M University - Galveston
      Galveston, Texas, United States
  • 2004
    • Fox Chase Cancer Center
      Filadelfia, Pennsylvania, United States