Changes to Glaucoma Surgery Patterns during the COVID-19 Pandemic: A Shift Toward Less Invasive Procedures

Glaucoma is a leading cause of blindness. Surgical and pharmacological treatment of glaucoma aims to lower the intraocular pressure (IOP) and preserve visual function. The severe acute res-piratory syndrome coronavirus 2 pandemic has placed a strain on the healthcare system. We aimed to compare the quantity, type of anti-glaucoma surgeries, and the disease stage before and during the coronavirus disease pandemic. We analyzed 362 eyes of 306 patients and 172 eyes of 149 patients from the pre-pandemic and pandemic groups, respectively. The number of an-ti-glaucoma surgeries was halved during the pandemic compared to a similar pre-pandemic pe-riod, with a significant difference in the procedural structures between the two groups (p<0.001). The most common procedures in the pre-pandemic group were Ex-Press implantation (33.7%) and trabeculectomy (31.5%). Within the pandemic group, half of the eyes underwent tra-beculectomy (50.0%), followed by Preserflo microshunt (11.6%). A significant difference in the average IOPs was revealed among patients who qualified for surgery 22.21 ± 7.83 mmHg in the pre-pandemic group and 25.16 ± 9.48 mmHg in the pandemic group; p<0.001). There was no significant difference in the best corrected visual acuity between the groups (p=0.263). Glaucoma treatment remained relatively accessible during the pandemic.

Medicine treatment of glaucoma in Australia 2012–2019: prevalence, incidence and persistence

ObjectiveMedical therapy can halt or significantly slow the progression of glaucoma if medicines are used in accordance with the guidelines. We used dispensing claims for a 10% sample of all Australians dispensed publicly subsidised glaucoma medicines to determine the prevalence and incidence of glaucoma medicine treatment and to examine treatment persistence between July 2012 and June 2019.MethodsWe estimated incidence and prevalence per 10 000 population for Australian financial years (1 July to 30 June). We defined prevalence as at least one dispensing of any glaucoma medicine and incidence as a dispensing of any glaucoma medicine with no previous dispensing during the preceding 12 months. We estimated duration of treatment for a cohort initiating glaucoma medicines and used Kaplan-Meier methods to estimate the proportion of people persisting on treatment at 6, 12, 18 and 36 months after initiation. We stratified analyses by the number of repeats prescribed at initiation, age, sex and medicine class.ResultsPrevalence remained stable over the study period at around 180/10 000 people/year; incidence was also stable around 36/10 000/year. Among 34 900 people initiating glaucoma medicines, 37.0% remained on treatment at 6 months from initiation, 29.8% at 12 months and 19.2% at 36 months. Median duration of treatment was 13.2 months (IQR: 2.5—not reached) for people initiating prostaglandin analogues and less than 3 months for those initiating other medicine classes.ConclusionPrevalence and incidence of glaucoma treatment have not changed in Australia over the past decade. Persistence to treatment increased with age but remained poor throughout the study period.

The Clinical Outcomes of Keratoplasty in Irreversible Corneal Decompensation Secondary to Axenfeld-Rieger Syndrome

Porpose To evaluate the clinical outcomes of penetrating keratoplasty (PK) and Descemet’s stripping automated endothelial keratoplasty (DSAEK) in eyes with irreversible corneal decompensation secondary to Axenfeld-Rieger syndrome (ARS).Methods In this retrospective case series, a total of 4 eyes undergoing PK and 7 eyes undergoing DSAEK, including 1 eye requiring 1 repeat DEASK, between 2014 and 2021 were enrolled. Postoperative complications, graft survival, glaucoma treatment before and after keratoplasty, visual outcomes, and endothelial cell density were recorded.Results The mean follow-up duration was 33.4 ± 16.8 months. Before keratoplasty, the mean BCVA was 2.0 ± 0.4 LogMAR, and the mean IOP was 21.6 ± 8.1 mmHg. 63.6% of eyes (7/11) received glaucoma treatment, including 5 eyes with glaucoma surgeries. After keratoplasty, 27.3% of eyes (3/11) exhibited secondary graft failure. The mean BCVA reached a maximum of 0.7 ± 0.5 LogMAR at 8.9 ± 7.5 months, with no significant difference between the PK and DSAEK groups (P1=1.00, P2=0.12). Four eyes with previous glaucoma surgeries exhibited markedly high IOP. 72.7% of eyes (8/11) required additional glaucoma treatments. The mean endothelial cell loss (ECL) rates at 1, 6, 12 and 24 months were 43%, 49%, 63% and 54%, respectively, with no significant difference between the PK and DSAEK groups (P1=0.64, P2=1.00, P3=0.57, and P4=0.44).Conclusion Both PK and DSAEK can successfully treat corneal decompensation secondary to ARS, resulting in similar outcomes with regard to IOP control, BCVA and ECL. IOP control is essential for postoperative management, especially for eyes with previous glaucoma surgeries.

Neuroprotective Effect of Statins in a Rat Model of Chronic Ocular Hypertension

Glaucoma is an optic neuropathy in which the degeneration of retinal ganglion cells (RGCs) results in irreversible vison loss. Therefore, neuroprotection of RGCs from glaucomatous afflictions is crucial for glaucoma treatment. In this study, we aimed to investigate the beneficial effects of statins in the protection of RGCs using a rat model. Glaucomatous injury was induced in rats by chronic ocular hypertension (OHT) achieved after performing a circumlimbal suture. The rats were given either statins such as simvastatin and atorvastatin or a solvent weekly for 6 weeks. Retina sections underwent hematoxylin and eosin, Brn3a, or cleaved casepase-3 staining to evaluate RGC survival. In addition, modulation of glial activation was assessed. While the retinas without statin treatment exhibited increased RGC death due to chronic OHT, statins promoted the survival of RGCs and reduced apoptosis. Statins also suppressed chronic OHT-mediated glial activation in the retina. Our results demonstrate that statins exert neuroprotective effects in rat retinas exposed to chronic OHT, which may support the prospect of statins being a glaucoma treatment.

TRPV4-induced Müller cell gliosis and TNF-α elevation-mediated retinal ganglion cell apoptosis in glaucomatous rats via JAK2/STAT3/NF-κB pathway

Background Glaucoma, the leading cause of irreversible blindness worldwide, is a type of retinal disease characterized by the selective death of retinal ganglion cells (RGCs). However, the pathogenesis of glaucoma has not been fully elucidated. Transient receptor potential vanilloid 4 (TRPV4) is a pressure-sensitive and calcium-permeable cation channel. TRPV4 is widely distributed in the retina and its sustained activation leads to RGC death; indicating that TRPV4 may be a possible target for glaucoma treatment. Here, we investigated the effects of TRPV4 on RGC apoptosis in a rat model of chronic ocular hypertension (COH), then examined the mechanism underlying these effects. Methods The COH model was established by injection of micro-magnetic beads into the anterior chamber of adult male rats. The expression levels of TRPV4, glial fibrillary acidic protein, and inflammatory factors were assessed by immunohistochemistry and immunoblotting. RGC apoptosis and visual dysfunction were evaluated by TUNEL assay and photopic negative response. Functional expression of TRPV4 was examined by electrophysiology and calcium imaging. Real-time polymerase chain reaction and immunoblotting were employed to investigate the molecular mechanism underlying the effects of TRPV4 on tumor necrosis factor-α (TNF-α) release. Results We found that TRPV4 played an essential role in glaucoma, such that high levels of TRPV4 expression were associated with elevated intraocular pressure. Furthermore, TRPV4 activation was involved in glaucoma-induced RGC apoptosis and RGC-related reductions in visual function. Mechanistic investigation demonstrated that TRPV4 activation led to enhanced Müller cell gliosis and TNF-α release via the JAK2/STAT3/NF-kB pathway, while TRPV4 inhibition could reverse these effects. Finally, TRPV4 activation could lead to elevated expression of TNF receptor 1 in RGCs, while inhibition of TNF-α could reduce TRPV4-mediated RGC apoptosis. Conclusions TRPV4 activation induces Müller cell gliosis and TNF-α elevation via the JAK2/STAT3/NF-κB pathway, which may exacerbate RGC apoptosis in glaucoma; these results suggest that TRPV4 can serve as a therapeutic target in glaucoma treatment.