Transient hypotony is the most common early complication after Preserflo MicroShunt (PMS) implantation. High myopia is a risk factor for the development of postoperative hypotony-related complications; therefore, it is advisable that PMS implantation in patients should be performed while employing hypotony preventive measures. The aim of this study is to compare the frequency of postoperative hypotony and hypotony-related complications in high-risk myopic patients after PMS implantation with and without intraluminal 10.0 nylon suture stenting. This is a retrospective, case–control, comparative study of 42 eyes with primary open-angle glaucoma (POAG) and severe myopia that underwent PMS implantation. A total of 21 eyes underwent a non-stented PMS implantation (nsPMS), while in the remaining eyes (21 eyes), PMS was implanted with an intraluminal suture (isPMS group). Hypotony occurred in six (28.57%) eyes in the nsPMS group and none in the isPMS group. Choroidal detachment occurred in three eyes in the nsPMS group; two of them were associated with the shallow anterior chamber and one was associated with macular folds. At 6 months after surgery, the mean IOP was 12.1 ± 3.16 mmHg and 13.43 ± 5.22 mmHg (p = 0.41) in the nsPMS and isPMS group, respectively. PMS intraluminal stenting is an effective measure to prevent early postoperative hypotony in POAG highly myopic patients.

Purpose: To describe a case of prolonged hypotony and choroidal detachment following insertion of a Preserflo™ MicroShunt in a patient with primary open-angle glaucoma (POAG). Case report: An 84-year-old Caucasian man with medically uncontrolled POAG developed refractory hypotony and choroidal detachment following a mitomycin C augmented Preserflo MicroShunt (PMS) insertion. Initial medical treatment with Dexamethasone 2 mg/mL and Atropine 1% for the hypotony (4 mmHg) and choroidal detachment was unsuccessful, BCVA decreased from the preoperative 20/28 to 20/60. After 90 days, surgery revision was carried out by inserting a 10-0 nylon monofilament suture through the distal end of the PMS reaching the opposite end of the tube. The free end of the nylon suture was exposed from the conjunctiva in the inferotemporal quadrant close to the fornix to ensure access to the occlusive stent. After one month intraocular pressure (IOP) was 7 mmHg, the choroidal detachment was completely regressed, and best corrected visual acuity (BCVA) increased to 20/28, at that time the exposed part of the stent was trimmed. 6 months after the revision surgery IOP was 14 mmHg, BCVA was 20/25, and the nylon stent was retained side to side inside the PMS lumen. Conclusion: The management of hypotony and choroidal detachment after a glaucoma drainage device (GDD) implantation is still unstandardized. The ab externo insertion of a nylon suture grants multiple advantages over the other techniques when performed on a PMS tube.

Purpose: To investigate whether standard keratometry (K) or total corneal power (TCP) leads to more accurate refractive outcomes for intraocular lens (IOL) power calculation. Setting: Public hospital. Design: Retrospective evaluation of a diagnostic test instrument. Methods: Preoperatively, all patients underwent optical biometry with Anterion, a swept-source optical coherence tomography device providing both K and TCP. The same IOL model was implanted in all cases. The whole sample was divided into a training dataset, used to optimize the formula constants, and a testing dataset, used to investigate the spherical equivalent prediction error (SEQ-PE) of 8 IOL power formulas. Trueness, precision, and accuracy were evaluated by means of the robust 2-sample t test. Cochran Q test was performed to assess whether the percentage of eyes with an SEQ-PE within each threshold was significantly different; in such an event, the McNemar test was then applied. Results: Both the training and testing datasets included 317 eyes. No significant differences were detected for trueness because of constant optimization. Precision and accuracy were better when K was entered, although a statistically significant difference was observed only with the EVO (precision: P = .02 and accuracy: P = .03) and Haigis (P < .01 for both precision and accuracy) formulas. No significant differences were observed for the percentage of eyes with an absolute SEQ-PE within any threshold. Conclusions: With most formulas, IOL power calculation is not more accurate when TCP is used instead of K.

Background To evaluate the association between COVID-19 vaccination and retinal vein occlusion (RVO). Methods This multicentre self-controlled case series included patients with RVO seen in five tertiary referral centres in Italy. All adults who received at least one dose of the BNT162b2, ChAdOx1 nCoV-19, mRNA-1273 or Ad26.COV2.S vaccine and had a first diagnosis of RVO between January 01, 2021, and December 31, 2021 were included. Incidence rate ratios (IRRs) of RVO were estimated using Poisson regression, comparing rates of events in a 28-day period following each dose of vaccination and in the unexposed control periods. Results 210 patients were included in the study. No increased risk of RVO was observed after the first dose (1–14 days IRR: 0.87, 95% CI: 0.41–1.85; 15–28 days IRR: 1.01, 95% CI: 0.50–2.04; 1–28 days IRR: 0.94, 95% CI: 0.55–1.58) and second dose of vaccination (1–14 days IRR: 1.21, 95% CI: 0.62–2.37; 15–28 days IRR: 1.08, 95% CI: 0.53–2.20; 1–28 days IRR: 1.16, 95% CI: 0.70–1.90). No association between RVO and vaccination was found in subgroup analyses by type of vaccine, gender and age. Conclusions This self-controlled case series found no evidence of an association between RVO and COVID-19 vaccination.