Relationship between angiographic and optical coherence tomographic (OCT) parameters for quantifying choroidal neovascular lesions.

BACKGROUND: To correlate the volume of various spaces on optical coherence tomography (OCT) with fluorescein angiographic (FA) parameters in neovascular age-related macular degeneration (AMD). METHODS: Sixty-five consecutive cases of active subfoveal choroidal neovascularization (CNV) associated with AMD were retrospectively collected. Area and greatest linear dimension of CNV lesion components were calculated on FA. Corresponding StratusOCT image sets were analyzed using custom software (termed OCTOR), which allows manual measurement of the volume of the neurosensory retina, subretinal fluid, subretinal tissue, and pigment epithelial detachment (PED). RESULTS: Area of occult CNV on FA correlated with PED (R = 0.62) and subretinal fluid (R = 0.28) volume and negatively with subretinal tissue volume (R = -0.26) on OCT. Area of classic CNV on FA correlated with subretinal tissue (R = 0.60) and retinal (R = 0.38) volume on OCT. Automated StratusOCT output values showed poorer correlations than manually calculated OCTOR values. CONCLUSIONS: OCT features of CNV lesions as measured by manual quantitative subanalysis correlate better with angiographic parameters than values provided by the automated StratusOCT analysis. These measures may improve our understanding of the morphologic effects of CNV lesions and may facilitate the development of a hybrid FA and OCT-based classification system for future clinical trials, which more fully characterizes CNV lesions.

Quantitative optical coherence tomography findings in various subtypes of neovascular age-related macular degeneration.

PURPOSE: To compare the volume of various spaces visible on optical coherence tomography (OCT) images in different angiographic lesion subtypes of neovascular age-related macular degeneration (AMD). METHODS: Sixty-six cases of previously untreated, active subfoveal choroidal neovascularization (CNV) associated with AMD were retrospectively collected. CNV lesions were classified as occult with no classic CNV, minimally classic CNV, predominantly classic CNV, or CNV lesions with associated retinal angiomatous proliferation (RAP). Corresponding OCT image sets were analyzed by trained graders using previously validated custom software that allows manual placement of boundaries on OCT B-scans. Spaces delineated by these boundaries included the neurosensory retina, subretinal fluid, subretinal tissue, and pigment epithelial detachments (PEDs). Volume measurements were calculated by the software and compared among groups. RESULTS: Minimally and predominantly classic CNV membranes demonstrated subretinal tissue on OCT in all cases and appeared to show a significantly greater volume of subretinal tissue than did the occult membranes. Subretinal fluid was present in all the predominantly classic cases. A PED was visible in all the occult CNV cases in our study, demonstrating less retinal thickening and significantly greater PED volumes than minimally and predominantly classic CNV lesions. Lesions associated with RAP showed the highest percentage of cystoid spaces. CONCLUSIONS: OCT and angiography provide complementary information regarding CNV lesions. Quantitative analysis of OCT images allows for an improved understanding of the anatomic characteristics of angiographically defined CNV lesion subtypes.

Quantitative subanalysis of optical coherence tomography after treatment with ranibizumab for neovascular age-related macular degeneration.

PURPOSE: To investigate the effects of ranibizumab on retinal morphology in patients with neovascular age-related macular degeneration (AMD) using optical coherence tomography (OCT) quantitative subanalysis. METHODS: Data from 95 patients receiving intravitreal ranibizumab for neovascular AMD were collected. StratusOCT images were analyzed using custom software that allows precise positioning of prespecified boundaries on every B-scan. Changes in thickness/volume of the retina, subretinal fluid (SRF), subretinal tissue (SRT), and pigment epithelial detachments (PEDs) at week 1 and at months 1, 3, 6, and 9 after treatment were calculated. RESULTS: Total retinal volume reached its nadir at month 1, with an average reduction of 0.43 mm(3) (P < 0.001). By month 9, this initial change had been reduced to a mean reduction of 0.32 mm(3) (P = 0.0011). Total SRF volume reached its lowest level by month 1, with an average reduction of 0.24 mm(3) (P < 0.001). This reduction lessened subsequently, to 0.18 mm(3), by month 9. There was an average 0.3-mm(3) decrease in total PED volume by month 1 (P < 0.001), and this later declined further, to 0.45 mm(3), by month 9 (P = 0.0014). Total SRT volume was reduced by an average of 0.07 mm(3) at month 1 (P = 0.0159) and subsequently remained constant. CONCLUSIONS: Although neurosensory retinal edema and SRF showed an early reduction to nadir after the initiation of ranibizumab therapy, the effect on the retina was attenuated over time, suggesting possible tachyphylaxis. PED volume showed a slower but progressive reduction. Manual quantitative OCT subanalysis may allow a more precise understanding of anatomic outcomes and their correlation with visual acuity.