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The LCCI had significantly better discriminating capability between POAG and healthy eyes than LCD. This finding suggests that the LCCI may serve better than the LCD for improved glaucoma management.

PurposeThis study examined the peripapillary choroidal thickness (PCT) in nonarteritic ischemic optic neuropathy (NAION) in comparison to contralateral eyes and normal eyes.MethodsWe used enhanced depth imaging spectral-domain optical coherence tomography to image the optic nerve head of 20 NAION, 10 contralateral eyes, and 102 normal eyes. Following compensation, the scans were manually delineated to identify relevant surfaces including Bruch's membrane opening (BMO), Bruch's membrane, and anterior sclera. The PCT was defined as the measurement between Bruch's membrane and the anterior sclera and was measured at increasing distance from BMO. Models adjusted for age, BMO area, and axial length were used to compare the mean PCT between NAION and normal eyes, and contralateral eyes and normal eyes. Paired t-tests were used to compare the PCT between NAION and contralateral eyes.ResultsThe mean PCT was thicker in NAION and contralateral eyes when compared with normal eyes at all distances from BMO (P < 0.001). The PCT was not significantly thicker in contralateral eyes when compared with affected NAION eyes. Choroidal thickness was thinnest in the inferior quadrant in all eyes regardless of the group.ConclusionsIncreased peripapillary choroidal thickness was noted in both NAION and contralateral eyes. The thicker choroid may be an associated feature or a result of the disorder. Although further longitudinal study is required to determine causation, these findings may suggest that a thickened peripapillary choroid may be a component of the disk-at-risk clinical phenotype.

Accurate and efficient identification of nerves is an essential component of peripheral nerve blocks. While ultrasound (US) imaging is increasingly used as a guidance modality, it often provides insufficient contrast for identifying nerves from surrounding tissues such as tendons. Electrical nerve stimulators can be used in conjunction with US imaging for discriminating nerves from surrounding tissues, but they are insufficient to reliably prevent neural punctures, so that alternative methods are highly desirable. In this study, an interventional multispectral photoacoustic (PA) imaging system was used to directly compare the signal amplitudes and spectra acquired from nerves and tendons ex vivo, for the first time. The results indicate that the system can provide significantly higher image contrast for discriminating nerves and tendons than that provided by US imaging. As such, photoacoustic imaging could be valuable as an adjunct to US for guiding peripheral nerve blocks.

PURPOSE. To investigate whether the lamina cribrosa (LC) curvature is decreased after trabeculectomy.METHODS. Thirty-nine eyes of 39 patients with primary open-angle glaucoma who underwent trabeculectomy were included. Optic nerves were scanned by using enhanced-depth-imaging spectral-domain optical coherence tomography before and after trabeculectomy. The LC curvature was assessed by measuring the LC curvature index (LCCI) in seven horizontal Bscan images in each eye. RESULTS.The LCCI was significantly smaller at postoperative 6 months than at the preoperative level in all seven planes (all P < 0.001). Preoperative LCCI was associated with younger age at superior midperiphery, midhorizontal plane, inferior midperiphery (all P 0.005) and higher preoperative intraocular pressure (IOP) at superior and inferior midperiphery (both P ¼ 0.039). Younger age and larger preoperative LCCI were associated with a larger reduction of the LCCI at all three locations (P ¼ 0.003 and 0.031 at superior midperiphery, P ¼ 0.011 and 0.001 at midhorizontal plane, and P ¼ 0.014 and 0.005 at inferior midperiphery, respectively), whereas the percentage IOP lowering was associated at superior and inferior midperiphery (P ¼ 0.017 and 0.047, respectively).CONCLUSIONS. Lamina cribrosa curvature was reduced after trabeculectomy. This finding suggests that LC curvature may have value as a parameter relevant to optic nerve head biomechanics.