Optical coherence tomography angiography for the detection of macular neovascularization—comparison of en face versus cross-sectional view

Purpose To evaluate sensitivity and specificity of swept source-optical coherence tomography angiography (SS-OCTA) en face images versus cross-sectional OCTA versus a combination of both for the detection of macular neovascularization (MNV). Design Prospective cohort study. Participants Consecutive patients with various chorioretinal diseases and subretinal hyperreflective material (SHRM) and/or pigment epithelial detachment (PED) on OCT possibly corresponding to MNV in at least one eye. Methods 102 eyes of 63 patients with fluorescein angiography (FA), OCT and SS-OCTA performed on the same day were included. FA images, the outer retina to choriocapillaris (ORCC) OCTA en face slab, a manually modified en face slab (‘custom slab’), cross-sectional OCTA and a combination of OCTA en face and cross-section were evaluated for presence of MNV. Main outcome measures Sensitivity and specificity for MNV detection, as well as the concordance was calculated using FA as the reference. Results OCTA en face imaging alone yielded a sensitivity of 46.3% (automated)/78.1% (custom) and specificity of 93.4% (automated)/88.5% (custom) for MNV detection. Cross-sectional OCTA (combination with en face) resulted in a sensitivity of 85.4% (82.9%) and specificity of 82.0% (85.3%). Concordance to FA was moderate for automated en face OCTA (κ = 0.43), and substantial for custom en face OCTA (κ = 0.67), cross-sectional OCTA (κ = 0.66) and the combination (κ = 0.68). Conclusion Segmentation errors result in decreased sensitivity for MNV detection on automatically generated OCTA en face images. Cross-sectional OCTA allows detection of MNV without manual modification of segmentation lines and should be used for evaluation of MNV on OCTA.

Swept Source Optical Coherence Tomography Assessment of Bursa Premacularis in Healthy Eyes

Purpose. To describe the reliability and the limits of bursa premacularis (BPM) evaluation using a swept source optical coherence tomography (SS-OCT) device with enface and 16 mm-high definition (HD) longitudinal scans. Methods. 60 eyes of 60 subjects were enrolled and imaged with SS-OCT system (PLEX Elite 9000, Carl Zeiss Meditec Inc., Dublin, CA, USA). BPM area was measured using enface scans imported to ImageJ. HD horizontal and vertical longitudinal scans centered at the fovea were used to detect width (W) and central thickness (CT) of BPM at baseline (T0) and after 30 minutes (T30) performed by two different observers. An enhanced vitreous visualization software provided by the manufacturer of the device was used to highlight vitreous structures. Results. BPM was identifiable in 100% of eyes using both horizontal and vertical longitudinal scans. On horizontal scan, BPM was not entirely measurable in 21.7% and in 18.3% of cases at T0 and T30, respectively. On vertical scan, BPM was not entirely measurable in 75.0% and in 81.7% at T0 and T30, respectively. No statistically significant differences were found between the two different time measurements with an intraclass correlation coefficient above 70%. Median BPM area was 26.9 (Q1-Q3: 19.5-40.5) mm2. In en face imaging, the most frequent BPM shape was the boat one. Conclusion. SS-OCT is a reliable tool for a detailed quantification and mapping of BPM, and it is able to add useful details about the morphological BPM features in youth population. However, the enhanced visualization of the vitreous structures is still a challenge, also with the most forefront devices.

Current Choroidal Imaging Findings in Central Serous Chorioretinopathy

Background: Central serous chorioretinopathy (CSCR) is a chorioretinal disease affecting mostly middle age males. It is marked by the serous detachment of the neurosensory layer at the macula. This review of the literature provides a framework of the current characteristic/relevant imaging findings of CSCR. Although the pathogenesis of CSCR is unclear, the choroid plays a major role and its changes are fundamental to the diagnosis and treatment of CSCR. Methods: A systematic literature search focusing on current multimodal imaging for CSCR was performed. Only articles reporting on original clinical data were selected, studies in a language other than English were included only if an English abstract was provided. Additional sources included articles cited in the references list of the first selected articles. We deduced imaging findings based on current and relevant literature on the topic. Results: We found that sub foveal choroidal thickness (SFCT) and choroidal vascularity index (CVI) were greater in eyes with acute CSCR than in eyes with chronic CSCR or normal eyes. There was increased choroidal thickness (CT) in the macula compared to peripapillary region. In healthy eyes, the highest CVI was found in the nasal region followed by the inferior, temporal, and superior quadrant. The area with the least CVI was the macula. In eyes with CSCR, 100% had asymmetric dominant vortex veins compared to 38% in normal eyes. Conclusion: Choroidal imaging has advanced the diagnosis of CSCR. This has led to numerous imaging biomarkers like CVI, CT, and hyper-reflective dots for early detection and possible prognostication of CSCR. More techniques like wide field scans and en face imaging are being employed to characterize the choroid in CSCR.