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Publications (2)5.6 Total impact

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    ABSTRACT: To compare optic disc changes using automated analysis of Heidelberg retina tomograph (HRT) images with assessments, by glaucoma specialists, of change in stereoscopic photographs. Baseline and follow-up stereophotographs and corresponding HRT I series of 91 eyes from 56 patients were selected. The selection criteria were sufficiently long, good-quality HRT series (7 visits in > or =70 months of follow-up) and follow-up photographs contemporaneous with the final HRT image. Topographic change analysis (TCA), statistic image mapping (SIM), and linear regression of rim area (RALR) across time were applied to HRT series. Glaucomatous change determined from stereophotographs by expert observers was used as the reference standard. Expert observers identified 33 eyes (36%) as exhibiting glaucomatous change. Altering HRT progression criteria such that 36% of eyes progressed according to each method resulted in concordance between HRT methods and stereophotograph assessment of 54% for TCA, 65% for SIM, and 67% for RALR (Cohen kappa = 0.05, 0.23, and 0.30, respectively). Receiver operating characteristic curves of the HRT analyses revealed poor precision of HRT analyses to predict stereophotograph-assessed change: areas under the curve were 0.61 for TCA, 0.62 for SIM, and 0.66 for RALR. Statistical methods for detecting structural changes in HRT images exhibit only moderate agreement with each other and have poor agreement with expert-assessed change in optic disc stereophotographs.
    Archives of ophthalmology 05/2010; 128(5):560-8. · 3.86 Impact Factor
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    ABSTRACT: PURPOSE:: To determine the clinical features of optic disc progression in patients with ocular hypertension and early glaucoma. PATIENTS:: A total of 336 eyes of 168 patients with ocular hypertension or early glaucoma. METHODS:: Two glaucoma specialists independently graded the baseline and most recent optic disc photographs for optic disc progression. Optic disc progression was defined as: new or increased neuroretinal rim thinning (2 or more clock hours), notching (1 clock hour or less of thinning of the neuroretinal rim), excavation (undermining of the neuroretinal rim or disc margin), and nerve fiber layer defect(s). They also determined the location of these changes. RESULTS:: Ninety-two of 336 eyes (27.4%) showed optic disc progression after a median of 6.1 years. Of those with progression, excavation occurred in 89% of eyes; rim thinning occurring in 54%; and notching occurring in 16%. Fifty-six percent (56%) had 2 or more features of progression. The inferotemporal quadrant was the most common location for progression, but more than 1 location of progression occurred in at least 30% of eyes with progression. CONCLUSIONS:: Optic disc progression occurred frequently in this cohort of ocular hypertension and early glaucoma patients. When evaluating the optic disc for glaucomatous progression, eye care providers should pay particular attention to increased excavation and neuroretinal rim thinning-especially in the inferotemporal quadrant.
    Journal of glaucoma 22(5):343-348. · 1.74 Impact Factor