Diagnostic ability of spectral-domain optical coherence tomography peripapillary retinal nerve fiber layer thickness to discriminate glaucoma patients from controls in an elderly population (The MONTRACHET study)

Refining glaucoma diagnosis and treatment in cataract surgery candidates: contribution of preoperative OCT retinal nerve fiber layer

PURPOSE

To evaluate the clinical significance of preoperative spectral domain optical coherence tomography (OCT) of the retinal nerve fiber layer (RNFL) thickness in identifying glaucoma and better managing patients scheduled for routine cataract surgery.

SETTING

Department of Ophthalmology, Shaare Zedek Medical Center, Jerusalem, Israel.

DESIGN

Retrospective cohort study.

METHODS

Consecutive patients scheduled for cataract surgery were enrolled from February 2022 to August 2022. Participants underwent routine OCT RNFL studies which were evaluated by a glaucoma specialist. Findings were compared with those of preoperative fundus biomicroscopic examinations conducted by the referring ophthalmologist. The main outcomes were the incidence of newly detected glaucoma based on OCT RNFL findings and the consequent changes in patient management.

RESULTS

In total, 486 patients met the inclusion criteria of whom 112 (23%) had abnormal RNFL. 31 patients (6.4%) had abnormal OCT RNFL findings attributed to comorbidities other than glaucoma, and 81 patients (16.7%) were suspected to have glaucoma based on their OCT RNFL findings, from which 44 patients (9%) were newly diagnosed with glaucoma or as glaucoma suspects, resulting in management modifications that included routine glaucoma follow-up (25 patients, 5.1%), initiation of intraocular pressure-lowering treatment (12 patients, 2.5%), and conversion to combined cataract-glaucoma surgery (7 patients, 1.4%).

CONCLUSIONS

OCT RNFL for cataract surgery candidates proved valuable in detecting glaucoma that had not been revealed by standard fundus biomicroscopic examination. The additional information provided by OCT RNFL can potentially enhance patient management and optimize outcomes.

Asian Race and Primary Open-Angle Glaucoma: Where Do We Stand?

Primary open-angle glaucoma (POAG) is an optic neuropathy characterized by irreversible retinal ganglion cell damage and visual field loss. The global POAG prevalence is estimated to be 3.05%, and near term is expected to significantly rise, especially within aging Asian populations. Primary angle-closure glaucoma disproportionately affects Asians, with up to four times greater prevalence of normal-tension glaucoma reported compared with high-tension glaucoma. Estimates for overall POAG prevalence in Asian populations vary, with Chinese and Indian populations representing the majority of future cases. Structural characteristics associated with glaucoma progression including the optic nerve head, retina, and cornea are distinct in Asians, serving as intermediates between African and European descent populations. Patterns in IOP suggest some similarities between races, with a significant inverse relationship between age and IOP only in Asian populations. Genetic differences have been suggested to play a role in these differences, however, a clear genetic pattern is yet to be established. POAG pathogenesis differs between Asians and other ethnicities, and it may differ within the broad classification of the Asian race. Greater awareness and further research are needed to improve treatment plans and outcomes for the increasingly high prevalence of normal tension glaucoma within aging Asian populations.

Macular Pigment and Open-Angle Glaucoma in the Elderly: The Montrachet Population-Based Study

(1) Background: To compare macular pigment optical density (MPOD) and its spatial distribution between eyes with primary open-angle glaucoma (POAG) and control eyes in an elderly population. (2) Methods: The Montrachet study (Maculopathy Optic Nerve and nutrition neurovAsCular and HEarT) is a population-based study including participants aged 75 years and over. All participants had a slit lamp examination, fundus photographs, and a questionnaire about their medical past history and smoking status. Optic disc spectral domain optical coherence tomography was also performed. All glaucoma-suspected patients were convocated to have a new full examination. We only retained one eye with POAG for analysis in the glaucoma group and one eye without optic neuropathy in the control participants group. MPOD measurements were performed with the two-wavelength autofluorescence method (488 and 514 nm). (3) Results: Overall, 601 eyes had MPOD measurements among 1153 participants. Among the 601 eyes, 48 had POAG. The mean age for the glaucoma and control participants was 84.01 ± 4.22 years and 81.94 ± 3.61 years, respectively (p < 0.001). In the multivariable analysis, we could not find any association between POAG and MPOD at 0.5° (p = 0.336). We found no significant difference regarding MP spatial distribution between the two groups (p = 0.408). (4) Conclusion: In this elderly population-based study, eyes with POAG and control eyes without optic neuropathy did not differ in terms of MPOD and MP spatial distribution.

Structural Changes in the Optic Disc and Macula Detected by Swept-Source Optical Coherence Tomography After Surgical Intraocular Pressure Reduction in Patients with Open-Angle Glaucoma

Purpose

To evaluate the magnitude of change in optic disc, peripapillary retinal nerve fiber layer (RNFL) and macular parameters measured by swept-source optical coherence tomography (SS-OCT) in glaucomatous eyes after filtration surgery, and to determine any possible relationship between these measurements and baseline factors.

Patients and Methods

This multicenter, prospective, consecutive observational study included patients with open-angle glaucoma who required glaucoma filtering surgery (surgical group, 29 eyes) and those with stable disease (control group, 25 eyes). Patients from the surgical group underwent measurement of optic disc, peripapillary retinal nerve fiber layer (RNFL) and macular parameters before and after surgery.

Results

In the surgical group, there was a significant increase in rim area and a significant decrease in the linear cup/disc ratio, vertical cup/disc ratio and cup volume 1 and 2 months postoperatively (p< 0.05). No significant change in the mean RNFL thickness and also sectorial measurements were observed from baseline to 1 and 2 months after surgery (p>0.05). Furthermore, significant increases in macular parameters were observed until 2 months after surgery (p<0.05). No significant changes were observed for all SS-OCT measurements in the control group. There was a significant correlation between the magnitude of the structural measurements change and the IOP reduction for two topographic parameters (rim area and linear cup-disc ratio) and macular average thickness 1 month and 2 months postoperatively.

Conclusion

In open-angle glaucoma patients submitted to surgical IOP reductions, improvements in topographic and macular OCT parameters measured by SS-OCT were observed for at least 2 months.

Prevalence of primary open-angle glaucoma in a Somalia population

PURPOSE

To determine the prevalence of primary open-angle glaucoma (POAG) in patients over 40 years that presented to our tertiary hospital in Somalia Mogadishu.

METHODS

This prospective cross-sectional study included 1550 patients older than 40 years that presented to the ophthalmology clinic of Somalia Mogadishu - Turkey Training and Research Hospital. The patients were evaluated in terms of age, gender, intraocular pressure, and optical cup/disk (C/D) ratio, and central corneal thickness measurements were taken.

RESULTS

The prevalence of glaucoma in the study population over the age of 40 years was 7%. The prevalence of glaucoma was 40% in the 40-50-year group, 6.8% in the 50-60-year group, 7% in the 60-70-year group, 9.9% in the 70-80-year group, and 12.3% in the 80-90-year group. The prevalence of glaucoma statistically significantly increased with advancing age (p < 0.001). The mean intraocular pressure was measured as 16.7 ± 3.3 mmHg for the overall patient population, 16.3 ± 2.9 mmHg for the female patients, and 17.1 ± 3.1 mmHg for the male patients. The mean intraocular pressure of the patients diagnosed with POAG was 27.3 ± 4.2 mmHg, and their mean corneal thickness was 507.9 µm, which was significantly lower than the value of the patients without POAG (545.8) (p < 0.001). The mean C/D ratio was calculated as 0.56 ± 0.21 for the patients with POAG and general 0.24 ± 0.16 for the overall patient population, indicating a statistically significant difference (p < 0.001).

CONCLUSIONS

A high rate of POAG is seen in patients over 40 years of age in Somalia. The mechanism underlying POAG needs to be investigated in this population.