Multimodal Imaging of Cotton Wool Spots in Branch Retinal Vein Occlusion.

PURPOSE: To describe and follow cotton wool spots (CWS) in branch retinal vein occlusion (BRVO) using multimodal imaging. METHODS: In this prospective cohort study including 24 patients with new-onset BRVO, CWS were described and analyzed in color fundus photography (CF), spectral domain optical coherence tomography (SD-OCT), infrared (IR) and fluorescein angiography (FA) every 3 months for 3 years. The CWS area on SD-OCT and CF was evaluated using OCT-Tool-Kit software: CWS were marked in each single OCT B-scan and the software calculated the area by interpolation. RESULTS: 29 central CWS lesions were found. 100% of these CWS were visible on SD-OCT, 100% on FA and 86.2% on IR imaging, but only 65.5% on CF imaging. CWS were visible for 12.4 ± 7.5 months on SD-OCT, for 4.4 ± 3 months and 4.3 ± 3.4 months on CF and on IR, respectively, and for 17.5 ± 7.1 months on FA. The evaluated CWS area on SD-OCT was larger than on CF (0.26 ± 0.17 mm(2) vs. 0.13 ± 0.1 mm(2), p < 0.0001). The CWS area on SD-OCT and surrounding pathology such as intraretinal cysts, avascular zones and intraretinal hemorrhage were predictive for how long CWS remained visible (r(2) = 0.497, p < 0.002). CONCLUSIONS: The lifetime and presentation of CWS in BRVO seem comparable to other diseases. SD-OCT shows a higher sensitivity for detecting CWS compared to CF. The duration of visibility of CWS varies among different image modalities and depends on the surrounding pathology and the CWS size.

Detection and Differentiation of Intraretinal Hemorrhage in Spectral Domain Optical Coherence Tomography.

PURPOSE: The purpose of this study was to classify and detect intraretinal hemorrhage (IRH) in spectral domain optical coherence tomography (SD-OCT). METHODS: Initially the presentation of IRH in BRVO-patients in SD-OCT was described by one reader comparing color-fundus (CF) and SD-OCT using dedicated software. Based on these established characteristics, the presence and the severity of IRH in SD-OCT and CF were assessed by two other masked readers and the inter-device and the inter-observer agreement were evaluated. Further the area of IRH was compared. RESULTS: About 895 single B-scans of 24 eyes were analyzed. About 61% of SD-OCT scans and 46% of the CF-images were graded for the presence of IRH (concordance: 73%, inter-device agreement: k = 0.5). However, subdivided into previously established severity levels of dense (CF: 21.3% versus SD-OCT: 34.7%, k = 0.2), flame-like (CF: 15.5% versus SD-OCT: 45.5%, k = 0.3), and dot-like (CF: 32% versus SD-OCT: 24.4%, k = 0.2) IRH, the inter-device agreement was weak. The inter-observer agreement was strong with k = 0.9 for SD-OCT and k = 0.8 for CF. The mean area of IRH detected on SD-OCT was significantly greater than on CF (SD-OCT: 11.5 ± 4.3 mm(2) versus CF: 8.1 ± 5.5 mm(2), p = 0.008). CONCLUSIONS: IRH seems to be detectable on SD-OCT; however, the previously established severity grading agreed weakly with that assessed by CF.

Response of retinal sensitivity to ranibizumab treatment of macular edema after acute branch retinal vein occlusion.

PURPOSE: To evaluate microperimetry changes in patients with acute macular edema secondary to branch retinal vein occlusion during a follow-up period of 12 months with intravitreal ranibizumab treatment (Lucentis; Novartis). METHODS: Patients with macular edema secondary to branch retinal vein occlusion received an intravitreous injection of 0.5 mg of ranibizumab (0.05 mL). Best-corrected visual acuity, Spectralis OCT (Heidelberg Engineering), and color fundus photography were performed at monthly intervals over a follow-up period of 1 year. Macular function was documented by microperimetry (Nidek, MP-1) at baseline, 3, and 12 months. RESULTS: Data of 20 patients without lack of microperimetry results were included to the statistical analyses. The size of the area of absolute scotoma was reduced from 16% at baseline to 11.7% at Month 3 and remained stable in the entire study duration (P > 0.05). Mean differential light threshold improved significantly under therapy from 9.47 dB at baseline to 12.53 dB at 12 months (P < 0.001). Best-corrected visual acuity correlated significantly with central millimeter thickness and mean retinal sensitivity at baseline and at 12-month follow-up visits. CONCLUSION: In addition to anatomical restoration and increased visual acuity, intravitreal ranibizumab also improved the central macular function in patients with acute macular edema after branch retinal vein occlusion.

Morphologic characteristics of idiopathic juxtafoveal telangiectasia using spectral-domain and polarization-sensitive optical coherence tomography.

PURPOSE: Idiopathic juxtafoveal telangiectasia (IJT) is characteristically associated with pigmentary changes. Polarization-sensitive spectral-domain optical coherence tomography (PS-SD-OCT) enables imaging of the retinal pigment epithelium (RPE) and similar melanin-containing structures based on specific polarization properties. This study examined IJT with the latest-generation SD-OCT and PS-SD-OCT, identifying pathophysiologically relevant characteristics of the retinal layers and RPE. METHODS: Twenty-two eyes of 12 patients with IJT were examined by PS-SD-OCT, with special focus on RPE detection and segmentation. Furthermore, SD-OCT technology (Cirrus, Spectralis, and 3D-OCT-1000) was applied. Characteristics of the retinal layers and RPE were evaluated. A classification system based on OCT characteristics of IJT was suggested. RESULTS: Polarization-sensitive spectral-domain optical coherence tomography together with SD-OCT identified characteristic patterns of IJT, used to classify eyes into three distinct groups. Group 1 (5 eyes) revealed discrete alterations in the inner retinal layers; group 2 (12 eyes) showed irregularities of the junction between the inner and outer photoreceptor segments with outer retinal atrophy but an intact RPE. Group 3 (5 eyes) revealed RPE irregularities and loss in addition to intraretinal alterations and photoreceptor abnormalities. CONCLUSION: This study described characteristic morphologic changes in IJT based on PS-SD-OCT and SD-OCT. Morphologic changes were classified, possibly leading to an OCT-based grading scheme. The intensity images of SD-OCT verified intraretinal and photoreceptor irregularities in great detail, whereas PS-SD-OCT additionally showed RPE alterations.

Response of retinal vessels and retrobulbar hemodynamics to intravitreal anti-VEGF treatment in eyes with branch retinal vein occlusion.

PURPOSE: To investigate whether intravitreal ranibizumab (0.05 mL) treatment affects retinal vessel diameters and retrobulbar blood velocities in patients with acute branch retinal vein occlusion (BRVO). METHODS: Thirty patients with clinically significant macular edema secondary to BRVO were included. The duration of the study was three months. Patients were studied before and one week, one month, two months, and three months after the first ranibizumab injection. Depending on the clinical requirements, up to three ranibizumab injections were administered. Retinal vessel diameters were measured using a retinal vessel analyzer. Flow velocities in the retrobulbar central retinal artery were measured using color doppler imaging. Best-corrected visual acuity was assessed using ETDRS charts. Measurements were done in the affected as well as in the contralateral eye. RESULTS: Three patients were lost for follow up. In the remaining 27 patients, significant vasoconstriction was observed in retinal veins (P < 0.001 versus baseline) and in retinal arteries (P = 0.001 versus baseline) of the affected eyes. In addition, a significant reduction in flow velocities was observed in the BRVO eyes over time (peak systolic velocity: P = 0.003, end diastolic velocity: P = 0.003). The reduction in retinal vessel diameters and flow velocities did not correlate with changes in visual acuity or number of re-treatments. In the contralateral eyes no change in retinal blood flow parameters was seen. CONCLUSIONS: BRVO is an ischemic retinal disease. Given that ranibizumab treatment reduces retinal perfusion in these eyes the potential long-term effects of this vasoconstriction need to be considered.

Performance of OCT segmentation procedures to assess morphology and extension in geographic atrophy.

PURPOSE: Investigating segmentation procedures and morphological findings in time domain (TD) and current spectral domain (SD) optical coherence tomography (OCT) devices in patients with geographic atrophy (GA). METHODS: Fifty eyes of 46 patients with GA secondary to AMD and 15 control eyes were examined in this prospective noninterventional comparative case series. All patients underwent Stratus (model 3000), Cirrus (Carl Zeiss Meditec), Spectralis (Spectralis HRA+OCT; Heidelberg Engineering) and 3D-OCT-1000 (Topcon). Automated segmentation analyses were compared. An overlay of scanning laser ophthalmoscope (SLO) and three-dimensional retinal thickness (RT) maps were used to investigate whether areas of retinal thinning correspond to areas of retinal pigment epithelium (RPE) atrophy. RESULTS: Geographic atrophy areas identified in SLO scans were significantly larger than areas of retinal thinning in RT maps. No convincing topographic correlation could be found between areas of retinal thinning and actual GA size as identified in SLO and fundus photography. Spectralis OCT showed significantly more mild and severe segmentation errors than 3D and Cirrus OCT. CONCLUSION: This study showed substantial limitations in identifying zones of GA reliably when using automatic segmentation procedures in current SD-OCT devices. This limitation should be addressed to visualize and document RPE loss realistically in a frequent disease like GA.