Navegando por Palavras-chave "choriocapillaris"

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    Swept source OCT angiography reveals choriocapillaris alterations in eyes with nascent geographic atrophy and drusen-associated atrophy
    (Lippincott Williams & Wilkins, 2016) Moult, Eric M.; Waheed, Nadia K.; Novais, Eduardo A.; Choi, Woojhon; Lee, Byungkun; Ploner, Stefan B.; Cole, Emily D.; Louzada, Ricardo Nogueira [UNIFESP]; Lu, Chen D.; Rosenfeld, Philip J.; Duker, Jay S.; Fujimoto, James G.
    Purpose: To investigate choriocapillaris (CC) alteration in patients with nascent geographic atrophy (nGA) and/or drusen-associated geographic atrophy (DAGA) using swept-source optical coherence tomography angiography (OCTA). Methods: A 1,050-nm wavelength, 400 kHz A-scan rate swept-source optical coherence tomography prototype was used to perform volumetric swept-source optical coherence tomography angiography over 6 mm x 6 mm fields of view in patients with nGA and/or DAGA. The resulting optical coherence tomography (OCT) and OCTA data were analyzed using a combination of en face and cross-sectional techniques. Variable interscan time analysis (VISTA) was used to differentiate CC flow impairment from complete CC atrophy. Results: A total of 7 eyes from 6 patients (mean age: 73.8 +/- 5.7 years) were scanned. Seven areas of nGA and three areas of DAGA were identified. Analysis of cross-sectional OCT and OCTA images identified focal alterations of the CC underlying all seven areas of nGA and all three areas of DAGA. En face OCTA analysis of the CC revealed diffuse CC alterations in all eyes. Variable interscan time analysis processing suggested that the observed CC flow alterations predominantly corresponded to flow impairment rather than complete CC atrophy. Conclusion: The OCTA imaging of the CC revealed focal CC flow impairment associated with areas of nGA and DAGA, as well as diffuse CC flow impairment throughout the imaged field. En face OCT analysis should prove useful for understanding the pathogenesis of nGA and DAGA and for identifying the formation of nGA and DAGA as endpoints in therapeutic trials.
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    Visualizing the Choriocapillaris Under Drusen: Comparing 1050-nm Swept-Source Versus 840-nm Spectral-Domain Optical Coherence Tomography Angiography
    (Assoc Research Vision Ophthalmology Inc, 2016) Lane, Mark; Moult, Eric M.; Novais, Eduardo Amorim [UNIFESP]; Louzada, Ricardo N.; Cole, Emily D.; Lee, ByungKun; Husvogt, Lennart; Keane, Pearse A.; Denniston, Alastair K.; Witkin, Andre J.; Baumal, Caroline R.; Fujimoto, James G.; Duker, Jay S.; Waheed, Nadia K.
    PURPOSE. To investigate the appearance of choriocapillaris (CC) flow under drusen by comparing long-wavelength (1050 nm) swept-source optical coherence tomography (SS-OCT) angiography with shorter-wavelength (840 nm) spectral-domain (SD) OCT angiography. METHODS. Patients with drusen imaged on both devices on the same day were selected and graded. Ambiguous OCT angiography (OCTA) signal loss was defined as low OCTA signal on the en face OCTA CC image that also had low OCT signal in the corresponding area on the en face OCT CC image and OCT B-scans. Unambiguous OCTA signal loss was defined as low OCTA signal on the en face OCTA CC image that did not have low OCT signal in the corresponding area on the en face OCT CC image and OCT B-scans. False-positive flow impairment on SS-OCTA was defined as ambiguous OCTA signal loss on SS-OCTA but no OCTA signal loss on SD-OCTA. False-positive flow impairment on SD-OCTA was defined as ambiguous OCTA signal loss on SD-OCTA but no OCTA signal loss on SS-OCTA. RESULTS. Nine eyes from seven patients were enrolled, 23 drusen were analyzed. On 840-nm SD-OCTA, 17 drusen (73.9%) exhibited OCTA signal loss. Fourteen (82.4%) were classified as ambiguous, and three (17.6%) were classified as unambiguous