Screening for glaucoma with Moorfields regression analysis and glaucoma probability score in confocal scanning laser ophthalmoscopy.

OBJECTIVE: To compare the validity of Moorfields regression analysis (MRA) and glaucoma probability score (GPS) of the confocal scanning laser ophthalmoscopy (Heidelberg retina tomograph 3; HRT3) in detecting glaucomatous optic nerve damage in a screening population. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: Subjects at high risk for development of open-angle glaucoma (OAG). METHODS: All subjects underwent confocal scanning ophthalmoscopy (Heidelberg retina tomograph; HRTII) testing, visual fields testing with frequency-doubling technology perimetry (FDT), and a standard ophthalmologic examination. All HRTII images were reprocessed with HRT3. Based on an ophthalmologic examination and FDT results, eyes were classified into 4 categories: normal, possible glaucoma, probable glaucoma, and definitive glaucoma. Main outcome measures included sensitivity and specificity of HRTII/MRA, HRT3/MRA, HRT3/GPS, and combination HRT3/MRA/GPS. RESULTS: The left eyes of 221 of 291 subjects were included; 4 (1.8%) eyes were classified as definitively having glaucoma. Depending on the reference standard diagnosis as well as on the borderline test-positive definition of the HRTII-3, sensitivity and specificity varied between 36.4% and 100%. For HRTII/MRA, 88.2% to 96.5%, 54.5% to 100%, and 74.5% to 93.6%; for HRT3/MRA, 61.9% to 100% and 64.3% to 85.2%; for HRT3/GPS, 85.7% to 100%; and for combination HRT3/MRA/GPS, 73.4% to 78.2%. CONCLUSIONS: In this pilot study, the MRA of the HRT3 appears to be more sensitive but less specific than the MRA in the HRTII version. The GPS, although somewhat less specific than MRA (and some discs are nonclassifiable by this technique), had greater sensitivity and as a screening method may have the additional advantage of being contour-line independent.

Combining rim area to disc area asymmetry ratio and Moorfields regression analysis of confocal scanning laser ophthalmoscopy for glaucoma screening.

OBJECTIVE: To determine the utility of combining rim area to disc area asymmetry ratio (RADAAR) and Moorfields regression analysis (MRA) to detect primary open-angle glaucoma (POAG) using confocal scanning laser ophthalmoscopy (CSLO) (Heidelberg retina tomograph 3 (HRT3)) in high-risk populations. DESIGN: Cross-sectional study. PARTICIPANTS: Subjects with high risk for developing POAG. METHODS: Subjects underwent HRT, frequency doubling technology perimetry (FDT), and complete ophthalmic examination. Based on an ophthalmologic examination and FDT results of the worse eye, subjects were classified into 4 categories: normal, possible glaucoma, probable glaucoma, and definite glaucoma. Main outcome measures included sensitivities (Se), specificities (Sp), positive and negative predictive values (PPV, NPV), and positive and negative likelihood ratios (PLR, NLR) of the MRA, RADAAR, and combined MRA- RADAAR tests. RESULTS: Of 375 subjects, 11 were classified as having definite glaucoma. Depending on the reference standard, range results for Se, Sp, PPV, NPV, PLR, and NLR were, respectively, 57.7% to 100%; 55.1% to 85.4%; 6.3% to 39%; 92.6% to 100%; 1.97 to 4.9; 0 to 0.49 for MRA; 11.5% to 27.3%; 98.1% to 98.8%; 30% to 60%; 87.4% to 97.8%; 9.29 to 14.1; and 0.74 to 0.89 for RADAAR; and 57.7% to 90.9%; 81.3% to 85.1%; 12.8% to 38.5%; 92.6% to 99.7%; 3.87 to 4.85; 0.11 to 0.50 for combination MRA-RADAAR. DISCUSSION: When using HRT in populations at high risk for glaucoma, RADAAR had a higher specificity than MRA in identifying glaucoma. When patients were classified as borderline on MRA, combining RADAAR values decreased the number of false-positives as well, and may be recommended when high specificity is required.

The validity of screening for open-angle glaucoma in high-risk populations with single-test screening mode frequency doubling technology perimetry (FDT).

PURPOSE: To evaluate whether a single frequency doubling perimetry (FDT) test is a valid screening tool to detect open-angle glaucoma (OAG) in high-risk populations. PATIENTS AND METHODS: All participants underwent frequency doubling Technology perimetry (FDT C-20-5 algorithm, Carl Zeiss Meditec Inc, Dublin, CA) and complete ophthalmic examination. FDT printouts were classified according to Iwasaki and Patel protocols. Gold-standard was clinical diagnosis of glaucomatous optic nerve damage. MAIN OUTCOME MEASURES: Sensitivity, specificity, positive predictive value, negative predictive value, positive, and negative likelihood ratios of a single-test screening FDT. RESULTS: Data of 445 right eyes and 408 left eyes of participants were analyzed. On the basis of clinical diagnosis, 19 right eyes (4.3%) and 20 left eyes (4.9%) had glaucoma. Depending on the gold standard used, the range of sensitivity was between 40.7% and 78.9%, 66% and 70% for specificity, 7.7% and 25.2% for positive predictive value, 82.3% and 98.6% for negative predictive value, 1.25 and 2.37 for positive likelihood ratio, and 0.32 and 0.87 for negative likelihood ratio. The κ coefficient of agreement between the FDT classifications as described by Iwasaki et al and Patel et al was 0.936 in right eyes and 0.935 in left eyes. CONCLUSIONS: The sensitivity and specificity of a single reliable screening FDT test were low. Thus, a single screening FDT test in even a high-risk population has poor validity and steps should be taken to better define the target population before testing, and enhance the FDT screening strategy.