Purpose To investigate the prevalence, locations, and characteristics of peripheral anterior synechiae (PAS) formation after microhook ab-interno trabeculotomy (µLOT), a minimally invasive glaucoma surgery, using a 360-degree gonio-camera, gonioscope GS-1 (NIDEK Co., Gamagori, Japan). Subjects and Methods A total of 105 consecutive eyes of 75 subjects with open-angle glaucoma were analyzed. The eyes had undergone µLOT or combined µLOT and cataract surgery as an initial glaucoma surgery. Postoperative PAS formation was evaluated in 16 iridocorneal angle images with the best focus covering 360 degrees in each eye. Results Compared to baseline, at 225±226 days postoperatively, the intraocular pressure and number of antiglaucoma medications decreased significantly (p<0.01, respectively). PAS developed in 86% of eyes. The mean number of iridocorneal angle images that showed PAS in all eyes was 4.1 (26%) in the total circumference, 3.1 (39%) within the µLOT incision, and 1.0 (13%) outside of the µLOT incision; the rate was significantly (p<0.0001) higher within the incision than outside of the incision. Moreover, the higher total PAS rate and that within the incision may be associated with later postoperative days (p=0.01 and 0.004, respectively), that outside of the incision with µLOT alone rather than the combined surgery, and with shallower preoperative central anterior chamber depth (p=0.048 and 0.04, respectively), calculated by the mixed-effect model. Conclusion The current results showed the characteristics of PAS formation after µLOT using 360-degree gonio-images, and the formation rate was significantly higher within the µLOT incision. The PAS within and outside of the incision had different causes.

Purpose The purpose of this study was to investigate the utility of automated focal plane merging with the collection of gonio-photographs with different depths of field (DOF) using an established focus-stacking algorithm. Methods A cross-sectional study was conducted at Shimane University Hospital, Izumo, Japan. Sixteen eyes from 16 subjects from the glaucoma clinic were included in this study. Image processing was performed for the images of 16 eyes from 16 angle sector following the successful gonio-photography. The 256 sets of focus-stacked and best-focused images were prepared in random order and were compared for the DOF and informativeness to diagnose angle pathology by masked observers in each set as the subjective assessments. Moreover, the energy of the Laplacian (average |Δ I |), which is an indicator of image sharpness between the photographs with and without the focus-stacking processing was also analyzed with the Laplacian filter as the objective assessment. Results The automated image processing was successfully performed in all stacks of images. The significant deepening of DOF and improvement of informativeness achieved in 255 (99.6%) and 216 (84.4%) images ( P < 0.0001 for both, sign test) and the energy of the Laplacian also significantly increased in 243 (94.9%) images ( P < 0.0001, sign test). Conclusions Focal plane merging by the automated algorithm can make the gonio-images deeper focus compared with the paired best-focused images subjectively and objectively, which would be useful for angle pathological assessment in clinical practice. Translational Relevance Focal plane merging algorithm for the automated gonio-photography can facilitate the angle assessment by providing informative deep-focus image, which would be useful for glaucoma care.