Comparison of SS-OCT and SD-OCT in polypoidal choroidal vasculopathy
Reviewed by Anjali Gupta

Swept source OCT (SS-OCT) is known to have a longer wavelength than spectral domain OCT (SD-OCT), allowing deeper penetration into retinal and choroidal layers. The aim of this study was to investigate whether SS-OCT is superior to SD-OCT in imaging important retina and choroidal features in polypoidal choroidal vasculopathy (PCV). Twenty eyes from 20 patients with treatment naïve PCV at a single centre were included in this study. Patients were diagnosed with PCV on ICGA findings by two retina specialists using the EVEREST criteria. All patients had an ocular examination and imaging with FFA, ICGA, SS-OCT and SD-OCT. Two retina specialists graded pre-specified OCT features for both the SS-OCT and SD-OCT in all patients. The pre-specified OCT features included presence of 1) a polyp, 2) a sharp and peaked pigment epithelial detachment (PED), 3) a notched PED, ability to visualise, 4) the full height of the PED, 5) the inner segment / outer segment (IS/OS) line, 6) the RPE line and 7) the choroid-scleral interface (CSI). Detection rate and agreement between the two OCTs were compared. At least one PCV lesion was detected in 17 eyes with SD-OCT and in 18 eyes using SS-OCT. Sharp peaked PED and notched PED were detected on both SD-OCT and SS-OCT in the majority of eyes. However, IS/OS line and CSI were visible in only nine eyes with SD-OCT compared with the IS/OS line being visible in 13 eyes and the CSI visible in 16 eyes using SS-OCT. The authors conclude that SS-OCT is superior in detecting the CSI but has comparable visibility for the other retina features in PCV when compared with SD-OCT. 

Comparison of swept source optical coherence tomography and spectral domain optical coherence tomography in polypoidal choroidal vasculopathy.
Ting DSW, Cheung GCM, Lim LS, Yeo IYS.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2015;43:815-9.