Effect of eplerenone on choroidal blood flow changes during isometric exercise in patients with chronic central serous chorioretinopathy.

PURPOSE: To investigate choroidal blood flow changes after isometric exercise in patients with chronic central serous chorioretinopathy nontreated or treated with mineralocorticoid receptor antagonists (MRA). METHODS: Foveolar choroidal laser Doppler flowmetry parameters - velocity (ChVel), volume (ChVol) and blood flow (ChBF) - of 22 eyes of 22 treated patients, 16 eyes of 16 untreated patients and 19 healthy controls were measured during a squatting test. Treatment consisted in MRA administration (eplerenone 50 mg/day or spironolactone 50 mg/day). The experiment comprised three successive periods: 30 seconds of rest, 2 min of continuous squatting exercise, and 150 seconds of recovery. Significance levels were calculated using a generalized estimating equation. RESULTS: During the squatting period, nontreated CSCR eyes had a similar change in ChVel (p = 0.8), ChVol (p = 0.8), ChBF (p = 0.5) and resistance to healthy eyes. Treated CSCR eyes exhibited significantly smaller changes in ChVel (-0.1 ± 11%, p = 0.04) than healthy eyes (6 ± 8%). No significant difference was found for ChVol and ChBF between the groups. The increase in ChVol from baseline in the nontreated CSCR group (4.4 ± 9%) was lower than that of treated group (6.7%±11%; p = 0.01). Finally, ChBF and ChVel changes in the CSCR groups were not significantly different. CONCLUSIONS: No abnormalities were detected in the changes in ChBF parameters during increased ocular perfusion pressure in nontreated CSCR patients compared with controls. MRA treatment in CSCR patients induced a significant reduction in ChBVel and an increase in ChBVol in response to isometric exercise, suggesting that MRA exerts effects on choroidal vascular changes.

Case Report: Central Retinal Artery Occlusion in a COVID-19 Patient.

We report a case of central retinal artery occlusion (CRAO) in a patient with a previous history of severe COVID-19 disease. This disease has been associated with inflammatory-induced homeostasis changes leading to endothelial dysfunction and a procoagulant state with multi-organ involvement, but the burden of thromboembolic complications in COVID-19 patients is currently unknown. The pathogenesis of retinal artery occlusions is a multifactorial process where inflammation and hypercoagulation state are established risk factors. Even if our experience may represent a coincidental relationship, it is likely that COVID-19 patients could be at risk of developing retinal vascular occlusions. A focused ophthalmological surveillance is advisable to prevent and manage this possible cause of severe vision loss that has an important impact in health care system.

pH Induced Conformational Transitions in the Transforming Growth Factor ß-Induced Protein (TGFßIp) Associated Corneal Dystrophy Mutants.

Most stromal corneal dystrophies are associated with aggregation and deposition of the mutated transforming growth factor-ß induced protein (TGFßIp). The 4(th)_FAS1 domain of TGFßIp harbors ~80% of the mutations that forms amyloidogenic and non-amyloidogenic aggregates. To understand the mechanism of aggregation and the differences between the amyloidogenic and non-amyloidogenic phenotypes, we expressed the 4(th)_FAS1 domains of TGFßIp carrying the mutations R555W (non-amyloidogenic) and H572R (amyloidogenic) along with the wild-type (WT). R555W was more susceptible to acidic pH compared to H572R and displayed varying chemical stabilities with decreasing pH. Thermal denaturation studies at acidic pH showed that while WT did not undergo any conformational transition, the mutants exhibited a clear pH-dependent irreversible conversion from αß conformation to ß-sheet oligomers. The ß-oligomers of both mutants were stable at physiological temperature and pH. Electron microscopy and dynamic light scattering studies showed that ß-oligomers of H572R were larger compared to R555W. The ß-oligomers of both mutants were cytotoxic to primary human corneal stromal fibroblast (pHCSF) cells. The ß-oligomers of both mutants exhibit variations in their morphologies, sizes, thermal and chemical stabilities, aggregation patterns and cytotoxicities.

Clinical Outcomes and Cataract Formation Rates in Eyes 10 Years After Posterior Phakic Lens Implantation for Myopia.

IMPORTANCE: Intraocular collamer lenses (ICLs) are posterior chamber phakic lenses that provide a refractive surgery option for those with high myopia or astigmatism. The short-term and midterm results indicate good refraction stability, efficacy, and safety. Cataract has been suggested to be an important long-term complication of ICL implantation. OBJECTIVE: To report the rates of cataract development and refractive outcomes 10 years after ICL implantation. DESIGN, SETTING, AND PARTICIPANTS: The study included 133 eyes of 78 patients undergoing consecutive V4 model ICL implantations, which took place from January 1, 1998, through December 31, 2004, at Jules-Gonin Eye Hospital, Lausanne, Switzerland. Data analysis was performed from January 1, 2014, to May 31, 2014. The lenses implanted were as follows: 53 V4 model ICLs of -15.5 D or greater, 73 V4 model ICLs of less than -15.5 diopter (D), and 7 V4 model toric ICLs for myopia. MAIN OUTCOMES AND MEASURES: Rate of cataract surgery, lens opacity, ocular hypertension, refractive safety, predictability, and stability. RESULTS: A total of 133 eyes of 78 patients (34 men and 44 women, with a mean [SD] age of 38.8 [9.2] years at enrollment) met the inclusion criteria. The rate of lens opacity development was 40.9% (95% CI, 32.7%-48.8%) and 54.8% (95% CI, 44.7%-63.0%) at 5 and 10 years, respectively. Phacoemulsification was performed in 5 eyes (4.9%; 95% CI, 1.0%-8.7%) and 18 eyes (18.3%; 95% CI, 10.1%-25.8%) at 5 and 10 years after ICL implantation, respectively. The vault height (distance between the posterior ICL surface and anterior lens surface) measured a mean (SD) of 426 (344) µm immediately postoperatively, decreasing to 213 (169) µm at 10 years. A smaller vault height was associated with the development of lens opacity and phacoemulsification (P = .005 and .008, respectively). The intraocular pressure was 15 mm Hg postoperatively, and there was no significant increase in intraocular pressure observed until the 10-year follow-up (16 mm Hg, P = .02). At 10 years, 12 eyes (12.9%; 95% CI, 5.6%-19.6%) had developed ocular hypertension that required topical medication. At 10 years, the mean (SD) safety index was 1.25 (0.57), with a manifest spherical equivalent of -0.5 D at 1-year postoperatively vs -0.7 D at 10 years postoperatively in eyes aimed at emmetropia. CONCLUSIONS AND RELEVANCE: This retrospective single center study indicates that ICL implantation provides good long-term safety and stability of refraction in patients with high myopia compared with similar short-term studies. However, the rates of cataract formation and ocular hypertension at 10 years have important clinical implications, and as such this information should be part of the available patient information before ICL implantation.