M. Y. Wang

Combining Nerve Fiber Layer Parameters to Optimize Glaucoma Diagnosis with Optical Coherence Tomography

PURPOSE To identify the best combination of Stratus optical coherence tomography (OCT) retinal nerve fiber layer (RNFL) thickness parameters for the detection of glaucoma. DESIGN Observational cross-sectional study. PARTICIPANTS Eighty-nine age-matched normal and perimetric glaucoma participants enrolled in the Advanced Imaging for Glaucoma Study. METHODS The Zeiss Stratus OCT system was used to obtain the circumpapillary RNFL thickness in both eyes of each participant. Right and left eye clock-hour data are analyzed together, assuming mirror-image symmetry. The RNFL diagnostic parameters were combined using either or-logic or and-logic approaches. MAIN OUTCOME MEASURES Area under the receiver operating characteristic curve (AROC), sensitivity, and specificity are used to evaluate diagnostic performance. RESULTS Overall average RNFL thickness has the highest AROC value (0.89) of all single parameters evaluated, followed by the inferior and superior quadrants (0.88 and 0.86, respectively). The clock hours with the best AROC values are in the inferior and superior quadrants. The highest AROC (0.92) was achieved by the or-logic combination of overall, inferior, and superior quadrant RNFL thicknesses. The 3-parameter combination was significantly better than the overall average alone (P = 0.01). The addition of more quadrants or clock hours to the combination reduced diagnostic performance. CONCLUSIONS The best stand-alone diagnostic strategy for Stratus OCT RNFL data is to classify an eye as glaucomatous if the overall, inferior quadrant, or superior quadrant RNFL thickness average is below normal.

Central retinal vein occlusion in Wegener’s granulomatosis without retinal vasculitis

The classic type of Wegener’s granulomatosis is characterised by necrotising granulomatous lesions of the upper and lower respiratory tracts, generalised focal necrotising vasculitis and glomerulonephritis, whereas the limited type has no renal involvement.1 Ocular manifestations occur in 30–50% of the patients,1 with retinal involvement less frequent and varying from 1 to 13% in the literature.2,3 We report a case of Wegener’s granulomatosis presenting with a central retinal vein occlusion (RVO) without clinical evidence of intraocular inflammation or retinal vasculitis. A 22-year-old white man presented with a 1-week history of intermittent obscuration of vision in his right eye. His medical history was remarkable for classic Wegener’s granulomatosis that had been in remission for the past year. His best-corrected visual acuities were 20/25 in the right eye and 20/20 in …

Combining information from 3 anatomic regions in the diagnosis of glaucoma with time-domain optical coherence tomography

Purpose:To improve the diagnosis of glaucoma by combining time-domain optical coherence tomography (TD-OCT) measurements of the optic disc, circumpapillary retinal nerve fiber layer (RNFL), and macular retinal thickness. Patients and Methods:Ninety-six age-matched normal and 96 perimetric glaucoma participants were included in this observational, cross-sectional study. Or-logic, support vector machine, relevance vector machine, and linear discrimination function were used to analyze the performances of combined TD-OCT diagnostic variables. Results:The area under the receiver-operating curve (AROC) was used to evaluate the diagnostic accuracy and to compare the diagnostic performance of single and combined anatomic variables. The best RNFL thickness variables were the inferior (AROC=0.900), overall (AROC=0.892), and superior quadrants (AROC=0.850). The best optic disc variables were horizontal integrated rim width (AROC=0.909), vertical integrated rim area (AROC=0.908), and cup/disc vertical ratio (AROC=0.890). All macular retinal thickness variables had AROCs of 0.829 or less. Combining the top 3 RNFL and optic disc variables in optimizing glaucoma diagnosis, support vector machine had the highest AROC, 0.954, followed by or-logic (AROC=0.946), linear discrimination function (AROC=0.946), and relevance vector machine (AROC=0.943). All combination diagnostic variables had significantly larger AROCs than any single diagnostic variable. There are no significant differences among the combination diagnostic indices. Conclusions:With TD-OCT, RNFL and optic disc variables had better diagnostic accuracy than macular retinal variables. Combining top RNFL and optic disc variables significantly improved diagnostic performance. Clinically, or-logic classification was the most practical analytical tool with sufficient accuracy to diagnose early glaucoma.

Ocular Determinants of Refractive Error and Its Age- and Sex-Related Variations in the Chinese American Eye Study.

Importance Uncorrected refractive error (RE) is a leading cause of visual impairment, and variations in ocular anatomy determine RE. The unique ocular determinants of RE in Chinese American individuals have not been studied previously. Objective To report ocular determinants of RE in a Chinese American population 50 years and older in Monterey Park, California. Design, Setting, and Participants The Chinese American Eye Study, a population-based, cross-sectional study, was conducted from February 1, 2010, through October 31, 2013, in Monterey Park, with this particular data analysis performed from January 1 through December 31, 2016. This study included data from 4582 participants who underwent an eye examination to obtain axial length (AL), central corneal thickness, vitreous chamber depth (VCD), anterior chamber depth (ACD), lens thickness (LT), corneal power (CP), noncycloplegic subjective refraction, and lens nuclear opalescence (NOP) grading. Data from the right phakic eye of each participant were used. Multiple regression models (standardized regression coefficients [SRCs] and semipartial correlation coefficients squared [SPCCs2]) identified key determinants of RE. Main Outcomes and Measures Ocular determinants of RE. Results Among the 4071 participants eligible for analysis (1496 men [36.7%] and 2575 women [63.3%]; mean [SD] age, 60.5 [8.1] years), mean (SD) RE was −0.52 (2.95) diopters (D), with no sex-related difference. A hyperopic shift occurred in women from −0.62 (2.95) D at 50 to 59 years to 0.60 (1.62) D at 80 years or older and in men from −0.69 (3.00) D at 50 to 59 years to 0.40 (2.29) D at 80 years or older (P < .001 for both). Compared with men, women had shorter AL (mean [SD], 23.62 [1.34] vs 24.14 [1.27] mm; P = .006), shorter ACD (mean [SD], 3.33 [0.34] vs 3.44 [0.34] mm; P < .001), and steeper CP (mean [SD], 43.50 [1.52] vs 42.88 [1.45] D; P = .02), after adjusting for age and height. No sex differences were found in VCD, LT, and NOP after height adjustment. Compared with younger individuals, older individuals had shallower ACD, thicker LT, and more NOP compared with younger individuals (P < .001 for both), even after adjustment for height. Axial length was the strongest determinant of RE (SRC = −0.92; SPCC2 = 0.55), followed by CP (SRC = −0.43; SPCC2 = 0.15). When individual components of AL were evaluated, VCD had the greatest contributing effect (SRC = −0.99; SPCC2 = 0.52), followed by CP (SRC = −0.47; SPCC2 = 0.15) and LT (SRC = −0.29; SPCC2 = 0.06). Conclusions and Relevance These data suggest that Chinese American individuals have longer AL and greater contribution of AL to RE than do Latino and other Chinese populations. Future studies should explore risk factors for increased AL in Chinese Americans and potential interventions that may ultimately prevent myopia-related disease.