Graefe's Archive for Clinical and Experimental Ophthalmology

The standardized definition of high myopia

Retraction Note to: A comparison of risk factors for age-related macular degeneration and polypoidal choroidal vasculopathy in Chinese patients The article "A comparison of risk factors for age-related macular degeneration and polypoidal choroidal vasculopathy in Chinese patients" has been retracted.

Midterm follow-up of immune reactions after Descemet membrane endothelial keratoplasty (DMEK)

Flap-sparing canaloplasty: a modified approach to Schlemm’s canal Abstract Purpose To present a modified surgical technique for canaloplasty with the Stegmann Canal Expander obviating the need for lamellar scleral dissection. Methods After limbal peritomy of the conjunctiva, the sclera is not dissected in the classic lamellar fashion with superficial and deep scleral flaps but is successively ‘scratched’ down by radial incision until Schlemm’s canal (SC) is opened (trench cut). Following canal opening and viscodilation with a microcannula and sodium hyaluronidate, one Stegmann Canal Expander is implanted on either side of the canal ostia and the scleral incision is closed watertight. Results Twenty-seven eyes with primary open-angle glaucoma (POAG) were consecutively operated on using this modified technique. In all eyes, SC was successively opened, but exposure of the choroid and rupture of trabeculo-Descemet’s membrane with iris prolapse or filtering blebs were not found. Adverse events included trimming of the expander in one eye for incomplete implantation during surgery, and transient microhyphaema in five eyes post-surgery. Mean intraocular pressure (IOP) was 31.9 mmHg ± 6.0 (SD) before surgery and 14.0 mmHg ± 2.5 (SD) 6 months and 15.2 mmHg ± 1.95 (SD) 12 months after surgery. Conclusions The flap-sparing, trench-cut incision technique may reduce the risk of complications in canaloplasty with the Stegmann Canal Expander while effectively lowering IOP in POAG patients.

The standardized definition of high myopia

Cost analysis of medications in ophthalmology consultations using Mobile applications

Focal retinal pigment epithelium atrophy at the location of type 3 neovascularization lesion: a morphologic feature associated with low reactivation rate and favorable prognosis Abstract Purpose To investigate the clinical significance of focal retinal pigment epithelium (RPE) atrophy in the eyes with type 3 neovascularization. Methods This retrospective study included 184 eyes those were diagnosed with type 3 neovascularization and were treated with antivascular endothelial growth factor (VEGF) therapy. Focal RPE atrophy was defined as a localized RPE atrophy found at the same location as the type 3 lesion. The incidence of reactivation after 3 loading injections and the visual outcomes was compared between a focal RPE atrophy group and a nonfocal RPE atrophy group. In the focal RPE atrophy group, the number of injections was compared between before and after the development of RPE atrophy. Results The mean follow-up period was 37.6 ± 18.8 months; focal RPE atrophy developed in 24 eyes (13.0%). Reactivation of the lesion after 3 loading injections was significantly less frequent in the focal RPE atrophy group (58.3%) than that in the nonfocal RPE atrophy group (85.0%) (P = 0.004). In the focal RPE atrophy group, the mean best-corrected visual acuity (BCVA) was 0.68 ± 0.28 (Snellen equivalent = 20/95) at diagnosis and 0.70 ± 0.48 (20/100) at the final follow-up. In the nonfocal RPE atrophy group, the values were 0.75 ± 0.34 (20/112) and 1.12 ± 0.68 (20/263), respectively. The BCVA at the final follow-up was significantly better in the focal RPE atrophy group (P < 0.001). The mean number of injections per year was 4.9 ± 1.8 and 1.3 ± 1.6 before and after the development of focal RPE atrophy, respectively (P < 0.001). Conclusions Development of focal RPE atrophy was associated with a low incidence of reactivation of type 3 neovascularization and was therefore predictive of a favorable visual prognosis.

Automated OCT angiography image quality assessment using a deep learning algorithm Abstract Purpose To expedite and to standardize the process of image quality assessment in optical coherence tomography angiography (OCTA) using a specialized deep learning algorithm (DLA). Methods Two hundred randomly chosen en-face macular OCTA images of the central 3 × 3 mm2 superficial vascular plexus were evaluated retrospectively by an OCTA experienced reader. Images were defined either as sufficient (group 1, n = 100) or insufficient image quality (group 2, n = 100) based on Motion Artifact Score (MAS) and Segmentation Accuracy Score (SAS). Subsequently, a pre-trained multi-layer deep convolutional neural network (DCNN) was trained and validated with 160 of these en-face OCTA scans (group 1: 80; group 2: 80). Training accuracy, validation accuracy, and cross-entropy were computed. The DLA was tested in detecting 40 untrained OCTA images (group 1: 20; group 2: 20). An insufficient image quality probability score (IPS) and a sufficient image quality probability score (SPS) were calculated. Results Training accuracy was 97%, validation accuracy 100%, and cross entropy 0.12. A total of 90% (18/20) of the OCTA images with insufficient image quality and 90% (18/20) with sufficient image quality were correctly classified by the DLA. Mean IPS was 0.88 ± 0.21, and mean SPS was 0.84 ± 0.19. Discrimination between both groups was highly significant (p < 0.001). Sensitivity of the DLA was 90.0%, specificity 90.0%, and accuracy 90.0%. Coefficients of variation were 0.96 ± 1.9% (insufficient quality) and 1.14 ± 1.6% (sufficient quality). Conclusions Deep learning (DL) appears to be a potential approach to automatically distinguish between sufficient and insufficient OCTA image quality. DL may contribute to establish image quality standards in this recent imaging modality.

Can perforations of descemet’s window (DW) improve the outcome of canaloplasty in open angle glaucoma? Abstract Purpose This study evaluates whether additional opening of the descemet’s window (DW) in canaloplasty has a positive effect on the intraocular pressure (IOP), glaucoma medication, visual acuity and postoperative complications and further interventions within the subsequent 12 months. This study also compares the difference of myopia and non-myopia based on the respective surgical method, as well as the quality of life after surgery by means of a questionnaire. Patients and methods This retrospective study included 114 patients who had a complete ophthalmic examination at baseline, as well as the first post-operative day and at 1, 3, 6, and 12 months following the procedure. The patients were divided into three groups: group 1 with intact DW (n = 35), group 2 with accidental rupture of the DW (n = 40), and group 3 with scheduled puncture of the DW (n = 39). Main outcome parameters were IOP reduction and the number of IOP-lowering medications. Intraoperative and postoperative complications were documented systematically. Results With a follow-up period of 12 months, all three groups showed statistically significant reductions in mean IOP and number of glaucoma medications as compared with preoperative values. At 12 months, group 1 (group 2/3) had a mean IOP reduction of 27.3% (33.1%/36.3%) and medication use reduction of 75% (82.6%/91.7%). Comparing the three surgical groups, there was no significant difference in terms of reduction of IOP and medication (p > 0.05) at all time points. Surgical complications were similarly rare. The number of subconjunctival blebs was statistically significantly different in the three groups (p < 0.05; group 1, 0%; group 2, 15%; group 3, 12.8%). Only in group 1, a revision after surgery was necessary in three cases. A significant difference concerning IOP, medication use, and visual acuity was not found between myopic eyes and non-myopic eyes after canaloplasty. The postop-surgical questionnaire showed that with 90.5% in group 1, 88.5% in group 2, and with 90.5% in group 3, the patients were highly satisfied with the results of surgery. Conclusion The intraoperative scheduled puncture of the DW in tendency showed better but no statistically significant results after 1 year regarding lowering of the IOP, the visual acuity, and postoperative medication usage. In addition, no increased risk of complications was observed in the myopic eye after the opening of the DW.

Dynamic intraoperative optical coherence tomography for inverted internal limiting membrane flap technique in large macular hole surgery Abstract Background/objectives To assess the efficacy of dynamic intraoperative spectral-domain optical coherence tomography (iSD-OCT) imaging for inverted internal limiting membrane (ILM) flap technique (IILMFT) in large macular hole (MH) surgery. Subjects/methods Prospective, non-randomized, observational study was conducted on 8 eyes of 7 patients with large, chronic and recurrent MHs, which were treated by pars plana vitrectomy (PPV) with IILMFT. All patients underwent standard pre- and postoperative examination. The iSD-OCT imaging was performed using microscope integrated systems before, during, and after ILM peeling. The iSD-OCT data were post-processed using graphic software and reviewed for tissue behavior and instruments position. Results The real-time iSD-OCT-assisted IILMFT allowed for real-time imaging of the entire surgery with visualization of the MH, vitreoretinal instruments, and all steps of inverted ILM flap formation. In spite of shadowing created by the steel instruments, it was possible to follow and control the distance between the instrument tips and retinal layers. Dynamic imaging of the surgical maneuvers including ILM peeling and mechanical apposition of MH edges revealed the iatrogenic impact on the retina (depression and appearance of hyporeflective zones). iSD-OCT imaging could confirm the proper position of the inverted ILM flap at the very end of the surgery after fluid-air exchange. Conclusions iSD-OCT imaging is an effective tool for learning and performing a well-controlled and safe inverted ILM flap technique in patients with large MH. Clinical significance of the structural iSD-OCT findings has to be further studied.