To investigate differences in peripapillary choroidal thickness (PPCT) between primary open-angle glaucoma (POAG), normal tension glaucoma (NTG), and healthy eyes, additionally comparing differences between POAG and NTG eyes.
Peripapillary choroidal thickness is a well-established OCT parameter in eyes with glaucoma and other ocular pathologies. The relationship between PPCT and glaucoma, if better understood, may facilitate the development of PPCT as a potential diagnostic and monitoring metric for glaucoma. In particular, there has yet to be a synthesis that directly compares PPCT between POAG eyes and NTG eyes.
A comprehensive literature search was performed on PubMed, EMBASE, and Cochrane Library, identifying studies from inception to December 2022. We included studies that measured PPCT using OCT in POAG, NTG, and healthy eyes. Mean difference (MD) among groups was calculated. Statistical analysis was performed using R version 4.2.0. Risk of bias of included studies was assessed using the Newcastle Ottawa Scale (NOS).
Eighteen studies were included in this meta-analysis, with a pooled total of 935 healthy control eyes, 446 NTG eyes, and 934 POAG eyes. There was a significant reduction of PPCT in POAG eyes compared with healthy eyes [MD = −16.32; 95% confidence interval (CI) (−27.55 to −5.09)]. Reduction in PPCT was also significant in NTG eyes compared with healthy eyes [MD = −34.96; 95% CI (−49.97 to −19.95)]. NTG eyes had significantly reduced PPCT compared with POAG eyes [MD = −26.64; 95% CI (−49.00 to −4.28)].
Glaucomatous eyes appear to have significantly reduced PPCT compared with normal healthy eyes. In addition, PPCT in NTG eyes appear significantly thinner compared with that in POAG eyes.
Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
To assess the accuracy of reused iCare probes after disinfection with 70% isopropyl alcohol and ethylene oxide gas compared to new iCare probes and Goldmann applanation tonometry (GAT).
Prospective comparative analysis.
A total of 118 eyes from 59 patients recruited from the Aravind Eye Hospital glaucoma clinic in Tirupati, South India.
Intraocular pressure (IOP) was measured on each eye using a new iCare tonometer probe, an iCare probe previously used and disinfected 1 time prior (once used probe) and 5 times prior (multiply used probe), as well as with GAT. Probes were disinfected after each use with 70% isopropyl alcohol swabs and ethylene oxide sterilization.
Agreement demonstrated with intraclass correlation coefficients (ICCs), mean difference in IOP values with limits of agreement, and Bland-Altman plots among IOP measurement approaches.
Compared to new iCare probes, both once used probes (ICC = 0.989, 95% confidence interval [CI] 0.985–0.993) and multiply used probes (ICC = 0.989, 95% CI 0.984–0.992) showed excellent agreement, and the mean difference in IOP was minimal for both once used probes (0.70 mmHg, 95% CI 0.29–1.11) and multiply used probes (0.75 mmHg, 95% CI 0.66–0.82) compared to new probes. Bland-Altman plots demonstrated minimal differences between new and reused probes across the spectrum of IOP. When comparing multiply used probes to once used probes, there was a high level of agreement (0.993) (95% CI 0.990–0.995) and negligible mean IOP difference 0.04 mmHg (95% CI 0.32–0.40). Additionally, ICC values for new probes (0.966, 95% CI 0.951–0.976), once used probes (0.958, 95% CI 0.940–0.971), and multiply used probes (0.957, 95% CI 0.938–0.970) compared to GAT were similar and all showed excellent agreement. Both new and reused iCare probes underestimated IOP by 2 to 3 mmHg compared to GAT.
In this prospective comparative analysis, we found that reusing iCare probes up to 5 times does not compromise the accuracy of IOP measurements when disinfected with 70% isopropyl alcohol swabs and ethylene oxide. Reusing iCare probes has the potential to transform care by reducing cost, decreasing environmental waste, and allowing for glaucoma screening camps and increased glaucoma monitoring in low resource settings leading to earlier identification and treatment of glaucoma.
Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
To describe the incidence, risk factors, clinical characteristics, and long-term outcomes of a hypertensive phase (HP) after glaucoma drainage device (GDD) implantation.
Retrospective cohort study.
Eyes that underwent implantation of their first GDD from January 2010 to October 2020 at a tertiary care center.
Hypertensive phase was defined as intraocular pressure (IOP) >21 mmHg occurring at 2 consecutive visits in the first 90 days after the date of surgery for Ahmed Glaucoma Valve (AGV) or in the first 90 days after tube opening for Baerveldt Glaucoma Implant (BGI). Generalized estimating equations and Fisher exact tests were used to evaluate risk factors for HP and risk factors for failure of GDD surgery after occurrence of a HP.
Incidence and risk factors for HP. Overall surgical success rates, defined as the absence of failure criteria: IOP >21 mmHg, ≤5 mmHg, or <20% reduction below baseline IOP after 3 months for 2 consecutive visits, with or without adjunctive ocular hypotensive therapy; additional glaucoma surgery; or loss of light perception.
Among 419 eyes of 360 patients that underwent GDD implantation, 42 (10.0%) eyes developed HP. Onset of HP was 20.8 ± 10.5 days after AGV and 11.7 ± 20.3 days from the date of tube opening after BGI. Mean IOP during HP was 26.5 ± 3.2 mmHg with peak IOP of 30.0 ± 5.9 mmHg. Median follow-up duration was 21.5 months after onset of HP. Younger age and neovascular glaucoma were significant risk factors for HP occurrence in a multivariable model. Resolution of HP occurred in 32 eyes (76.2%) after a mean duration of 48.0 ± 53.0 days. Additional surgery with a second GDD or cyclophotocoagulation was performed for 12 eyes (28.6%). The overall success rate among eyes with a HP was 52.6% at 2 years, which was significantly lower than that observed among control eyes that did not experience HP (76.3%), P < 0.01.
The incidence of HP was 10.0%. Younger age and neovascular glaucoma were significant risk factors for HP in the multivariable model. The risk of surgical failure after HP is significantly higher compared to eyes that did not experience HP.
Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
To evaluate the efficacy and safety of combined cataract surgery with insertion of an ab interno trabecular microbypass device (iStent Inject, Glaukos Corporation) compared to cataract surgery alone in patients with mild-to-moderate glaucoma.
Prospective, randomized, assessor-masked controlled trial at a single centre.
Eyes with visually-significant cataract and mild-to-moderate glaucoma with preoperative intraocular pressure (IOP) of 12 to 30 mmHg on 0 to 3 ocular hypotensive medications.
Participants eyes were randomized (2017–2020) 1:1 to combined cataract surgery with iStent Inject (treatment group, n = 56) or cataract surgery alone (control group, n = 48), and followed up for 2 years.
The co-primary effectiveness endpoints were the number of ocular hypotensive medications and IOP at 24-months post-surgery. The secondary effectiveness endpoints were ocular comfort as measured by the Ocular Surface Disease Index (OSDI) and vision-related quality of life as measured by the Glaucoma Activity Limitation Questionnaire (GAL-9) at 24-months. Safety measures included postoperative visual acuity, any unplanned return to the operating theatre, adverse events, and complications.
Participants (67.3% male) were aged 53 to 85 years, and treatment groups were similar in terms of mean medicated IOP (treatment group 17.7 mmHg ± 4.0; control group 17.1 mmHg ± 3.1), and number of ocular hypotensive medications (treatment group 1.69 ± 1.05; control group 1.80 ± 1.22) at baseline. At 24 months, the number of ocular hypotensive medications were 0.7 ± 0.9 in the treatment groups compared to 1.5 ± 1.9 in the control group, with an adjusted difference of 0.6 fewer medications per eye in the treatment group (95% CI 0.2–1.1, P = 0.008). In the treatment group, 57% of eyes were on no glaucoma medications compared to 36% in the control group. There was no significant difference in IOP between the 2 groups beyond the 4-weeks. There were no differences in patient-reported outcomes between the 2 groups. The visual outcomes and safety profiles were similar between the 2 groups.
Combined cataract surgery with iStent Inject achieved a clinically- and statistically-significantly greater reduction in ocular hypotensive medication usage at 24-months compared to cataract surgery alone, with no significant difference in IOP.
Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.