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AimsTo compare the biomechanically corrected intraocular pressure (IOP) estimate (bIOP) provided by the Corvis-ST with Goldmann applanation tonometry (GAT-IOP) in patients with high-tension and normal-tension primary open-angle glaucoma (POAG; HTG and NTG), ocular hypertension (OHT) and controls. Moreover, we compared dynamic corneal response parameters (DCRs) of the Corvis-ST in POAG, OHT and controls, evaluated the correlation between global visual field parameters mean deviation and pattern SD (MD and PSD) and DCRs in the POAG group.Methods156 eyes of 156 patients were included in this prospective, single-centre, observational study, namely 41 HTG and 33 NTG, 45 OHT cases and 37 controls. Central corneal thickness (CCT), GAT-IOP and bIOP were measured, GAT-IOP was also adjusted for CCT (GATAdj). DCRs provided by Corvis-ST were evaluated, MD and PSD were recorded by 24–2 full-threshold visual field. To evaluate the difference in DCRs between OHT, HTG and NTG, a general linear model was used with sex, medications and group as fixed factors and bIOP and age as covariates.ResultsThere was a significant difference between GAT-IOP, GATAdj and bIOP in NTG and HTG, OHT and controls. NTG corneas were significantly softer and more deformable compared with controls, OHT and HTG as demonstrated by significantly lower values of stiffness parameters A1 and highest concavity and higher values of inverse concave radius (all p<0.05). There was a significant correlation (p<0.05) between MD, PSD and many DCRs with POAG patients with softer or more compliant corneas more likely to show visual field defects.ConclusionsCorneal biomechanics might be a significant confounding factor for IOP measurement that should be considered in clinical decision-making. The abnormality of corneal biomechanics in NTG and the significant correlation with visual field parameters might suggest a new risk factor for the development or progression of NTG.

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Purpose Two-year post-operative outcomes of both deep sclerectomy (DS) and trabeculectomy surgery (Trab) augmented with Mitomycin C (MMC) at a single tertiary eye centre. Methods Retrospective review of DS + MMC and trabeculectomy + MMC at a single centre between February 2015 and March 2018. Patients with a minimum of 12-month follow-up were included. Post-operative follow-up: day 1, week 1, months 1/3/6/12/18/24. Primary outcomes: changes in intraocular pressure (IOP) and changes in LogMAR visual acuity (BCVA) pre- and post-procedure. Secondary outcomes: changes in number of eye drops, number of follow-up clinic visits, post-operative complications and further surgical interventions. Complete success: IOP ≤ 21 mmHg off all IOP-lowering medications. Qualified success: IOP ≤ 21 mmHg on medication. Failure: IOP > 21 mmHg at 24 months or ≤ 5 mmHg on 2 consecutive follow-up visits after 3 months +/− additional incisional glaucoma surgery +/− loss of light perception. Statistical analysis performed using Microsoft Excel + SPSS. Results 90 eyes: DS + MMC = 46 eyes, Trab + MMC = 44 eyes. DS + MMC v Trab + MMC: mean pre-op IOP = 19.57 mmHg v 18.89 mmHg, significantly reduced at all post-operative time-points for both groups ( p < 0.001). Mean IOP reduction from baseline = 33.94% v 38.39%; > 30% IOP reduction = 54.35% v 68.18%. IOP ≤ 16 mmHg = 82.61% (38/46) v 95.46% (42/44), IOP ≤ 12 mmHg = 52.17% (24/46) v 72.72% (32/44). Complete success = 67.39% v 61.36%, qualified success = 26.09% v 29.55%, failure = 6.52% v 9.09%. Post-op BCVA: no statistically significant differences between two groups ( p = 0.09). Mean pre-op drops v post-op drops = 2.98 v 0.38 (DS + MMC; p < 0.001); 2.68 v 0.39 (Trab + MMC; p < 0.001). Further surgical intervention = 13% v 29.55%. Mean number of post-op clinic visits DS + MMC v Trab + MMC = 10.09 v 13.02 ( p = 0.005). Conclusion Both procedures achieve sustained intraocular pressure and drop reduction at 2 years post-op. DS + MMC has lower complication rates requiring less intervention and significantly fewer clinic visits, which may be an important factor for deciding surgical management of glaucoma patients in the era of Covid-19 to reduce patient/clinician exposure to the virus.

AGV implantation offered good long-term IOP control with a success rate of 78.7%. The authors recommend C3F8 gas fill and temporary tube ligation in eyes at high risk of postoperative hypotony and the use of donor sclera or human pericardial patch to prevent tube erosion.