Anna K. Junk

Précis: In patients with significant preoperative comorbidities, prolonged activity restrictions beyond 2 weeks after Xen45 surgery may mitigate the risks of delayed SCH. Purpose: To report the first case to date of delayed suprachoroidal hemorrhage (SCH) not associated with hypotony 2 weeks after the placement of the Xen45 gel stent. Case Summary: An 84-year-old white man with significant cardiovascular comorbidities underwent uneventful ab externo implantation of a Xen45 gel stent for asymmetric progression of severe primary open angle glaucoma. The patient had a reduction in intraocular pressure by 11 mm Hg on postoperative day 1 and maintained preoperative visual acuity. The intraocular pressure remained stable at 8 mm Hg on multiple postoperative visits until the patient developed a SCH at postoperative week 2 immediately after a light session of physical therapy. The patient was treated medically with topical cycloplegic, steroid, and aqueous suppressants. He maintained preoperative visual acuity throughout the postoperative course and had resolving SCH without the need for surgical intervention. Conclusions: This is the first report of a delayed presentation of SCH in the absence of hypotony after ab externo implantation of the Xen45 device. The possibility of this vision-threatening complication should be considered as part of the risk assessment and included in the consent process for the gel stent. In patients with significant preoperative comorbidities, prolonged activity restrictions beyond 2 weeks after Xen45 surgery may mitigate the risks of delayed SCH.

Scleral buckling procedures create a challenge for intraocular pressure (IOP) control in the glaucoma patient. The encircling band is believed to compress vortex veins, causing increased episcleral venous pressure, a proposed mechanism for secondary glaucoma. Glaucoma drainage device implantation is preferred over trabeculectomy when medical management fails, but often involves modification of the glaucoma implant and manipulation of the fibrotic capsule surrounding the scleral buckle. This case demonstrates that ab externo XEN gel stent implantation may successfully reduce IOP without interfering with the previous scleral buckle, a major limitation of previous glaucoma filtering surgeries. [ Ophthalmic Surg Lasers Imaging Retina. 2020;51:289–292.]

Pseudoexfoliation (PEX) is a known cause of secondary open angle glaucoma. PEX glaucoma is associated with structural and metabolic changes in the eye. Despite similarities, PEX and primary open angle glaucoma (POAG) may have differences in the composition of metabolites. We analyzed the metabolites of the aqueous humor (AH) of PEX subjects sequentially first using nuclear magnetic resonance (¹H NMR: HSQC and TOCSY), and subsequently with liquid chromatography tandem mass spectrometry (LC-MS/MS) implementing isotopic ratio outlier analysis (IROA) quantification. The findings were compared with previous results for POAG and control subjects analyzed using identical sequential steps. We found significant differences in metabolites between the three conditions. Principle component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) indicated clear grouping based on the metabolomes of the three conditions. We used machine learning algorithms and a percentage set of the data to train, and utilized a different or larger dataset to test whether a trained model can correctly classify the test dataset as PEX, POAG or control. Three different algorithms: linear support vector machines (SVM), deep learning, and a neural network were used for prediction. They all accurately classified the test datasets based on the AH metabolome of the sample. We next compared the AH metabolome with known AH and TM proteomes and genomes in order to understand metabolic pathways that may contribute to alterations in the AH metabolome in PEX. We found potential protein/gene pathways associated with observed significant metabolite changes in PEX.

A 56-year-old Hispanic male individual with moderate primary open-angle glaucoma on maximal tolerated topical therapy with recent visual field progression presented with excessive glare due to cataract in the right eye. The patient underwent uncomplicated phacoemulsification with supraciliary microstent implantation. Ten weeks postoperatively, he presented with global Descemet folds and focal corneal edema overlying the CyPass implant despite apparent adequate implant position (1 retention ring visible). The revision proved challenging as the anterior chamber portion of the implant was short. Nonetheless, the device was trimmed under gonioscopic view using intraocular lens cutting scissors and a Sinskey hook. Postoperatively, the implant was flush with the iris root with a patent lumen. Bilateral global guttae indicating unrecognized Fuchs endothelial corneal dystrophy diagnosed postoperatively may have contributed to the corneal edema that improved after the revision.

Introduction: This retrospective consecutive case series examined whether training on a surgical simulator reduces intraoperative complication rates among novice ophthalmology residents learning cataract surgery. Methods: Beginning July 2014, training on the Eyesi simulator became mandatory for novice postgraduate year 3 ophthalmology residents before live cataract surgery at our institution. Complication rates of the 11 simulator-trained residents (study group) were compared with their immediate 11 simulator-naive predecessors (comparison group). Only straightforward cataract cases (according to standardized preoperative criteria) where postgraduate year 3 residents served as the primary surgeon were included. Complication data were obtained from Morbidity and Mortality records and compared using Fisher exact test. A survey was administered to the residents to gauge the perceived utility of simulation training. Results: The simulator-trained group (n = 501 cataract cases) and the simulator-naive comparison group (n = 454 cases) were analyzed. The complication rate in the simulator group was 2.4% compared with 5.1% in the comparison group (P = 0.037, Fisher exact test). Both the mean posterior capsule tear rate and vitreous prolapse rate in the simulator group were 2.2% compared with 4.8% in the comparison group (P = 0.032, Fisher exact test). The survey had a response rate of 100% (11/11), and 91% (10/11) of respondents felt that the training was “extremely worthwhile” and should be mandatory. Conclusions: The addition of surgical simulation training was associated with a significantly reduced rate of complications, including posterior capsule tears and vitreous prolapse, among novice postgraduate year 3 residents. There is a perceived utility among residents to incorporate virtual simulation into surgical training.