Comparison of spectral-domain and high-penetration OCT for observing morphologic changes in age-related macular degeneration and polypoidal choroidal vasculopathy.

BACKGROUND: We compared the visibility of retinal and choroidal pathologies using high-penetration optical coherence tomography (HP-OCT) with a long-wavelength light source (1,050 nm) and conventional spectral-domain OCT (SD-OCT) in age-related macular degeneration (AMD).
METHODS: One hundred and forty-six eyes were included: 63 eyes with AMD, 79 eyes with polypoidal choroidal vasculopathy (PCV), and four eyes with retinal angiomatous proliferation. The SD-OCT and HP-OCT images were compared using the grading criteria to grade the visibility of the retinal changes, the line corresponding to the retinal pigment epithelium (RPE), and the chorioscleral interface (CSI). In 132 eyes with a pigment epithelial detachment (PED), we graded the structures inside the PED, Bruch's line, and the CSI. We compared the visibility of those changes in eyes with subretinal hyperreflective changes due to a subretinal hemorrhage (SRH) (n = 17) or a hemorrhage inside the PED (HPED) (n = 12).
RESULTS: HP-OCT provided superior visibility of the following structures compared to SD-OCT (P < 0.01): the CSI, structures inside the PED, Bruch's line inside the PED, the CSI inside the PED, SRH, type 1 CNV, polyps, and HPED. There were no significant differences between the two OCT devices in the scores for the RPE line, retinal morphology, or type 2 CNV and/or fibrin.
CONCLUSION: HP-OCT visualizes morphologies beneath the RPE better than SD-OCT, and is equivalent to SD-OCT for visualizing morphologies above the RPE.