Anterior chamber depth and angle-closure glaucoma after central retinal vein occlusion

Retinal vein occlusion in patients with primary angle closure: a prospective case-control study

OBJECTIVE

To compare the prevalence of angle closure in eyes with retinal vein occlusion (RVO) with control eyes and assess the possible association between angle-closure and RVO.

PATIENTS AND METHODS

This prospective, blinded case-control study included patients with a history of RVO (cases) and control individuals matched for age and refractive error. Clinical characteristics and angle-based structures derived from anterior-segment optical coherence tomography (AS-OCT) were analyzed.

RESULTS

Eighty-eight patients (44 per group) were included. The average age of the RVO and control groups was 59.8 ± 11.6 years and 60.8 ± 9.0 years, respectively (p = 0.667). There were no significant differences in terms of clinical characteristics between the 2 groups, including intraocular pressure (p = 0.837) and Shaffer gonioscopy grading (p = 0.620). None of the AS-OCT-derived angle characteristics were significantly different between the 2 groups. The number of angle-closure diagnoses between the RVO group (1 primary angle closure and 7 primary angle-closure suspects) and the control group (6 primary angle-closure suspects) did not differ significantly (p = 0.560). Anterior-chamber depth (ACD) was shallower in RVO eyes (2.72 ± 0.31 mm) than in the contralateral non-RVO eyes (2.76 ± 0.31 mm; p = 0.014).

CONCLUSIONS

This prospective, blinded, matched case-control study did not evidence any significant differences in clinical and AS-OCT-derived structural measures between RVO and control eyes. However, RVO eyes, compared with their contralateral non-RVO eyes, had a slightly shallower ACD. These findings collectively suggest that an association between primary angle-closure mechanisms and RVO is unlikely. However, the shallower ACD in RVO eyes could potentially put them at higher risk for intermittent or permanent pupillary block.

Association of primary angle-closure disease in patients with retinal vein occlusion in North Indian population

Purpose

To determine the association of primary angle-closure disease (PACD) in patients with retinal vein occlusion (RVO) at a tertiary eye care center in North India.

Methods

It is a cross-sectional, observational study. Sixty consecutive patients with retinal vein occlusion within a period of one year from a single tertiary eye care center were enrolled. Detailed history, slit-lamp examination of the anterior segment, intraocular pressure measurement by applanation tonometry, gonioscopy and fundus examination were done. Anterior chamber depth and axial length were also measured.

Results

Among the 60 patients, 29 were males (48.3%) and 31 females (51.6%). Twenty-seven (45%) of them had central retinal vein occlusion (CRVO) and 33 (55%) had branch retinal vein occlusion (BRVO). Forty percent of patients with RVO had PACD. Relative risk of PACD was 1.71 times in patients with CRVO as compared to BRVO. Risk of glaucoma was 49% more in CRVO than BRVO. Probability of PACD was more in patients of RVO who had diabetes and CAD as comorbidity.

Conclusion

The association between PACD and RVO is less known. PACD can be one of the risk factors for the development of RVO. A comprehensive examination and detailed angle evaluation of both of the eyes should be done in all cases of RVO, in addition to investigating for systemic risk factors. However, larger population-based studies would be required to prove it as an independent risk factor.

Intraocular pressure modifications in patients with acute central/hemicentral retinal vein occlusions

Intraocular pressure (IOP) modifications in patients with acute central/hemicentral retinal vein occlusions (RVOs) consist in IOP reductions and increases. The IOP reduction is due to a transitional hyposecretory phase of the aqueous humor, that increases gradually until 3mo after the venous occlusion onset, and then finally disappears after month 4^th. The IOP increases lead to the ocular hypertension and glaucoma. The possible pathogenetic correlations between ocular hypertension/glaucoma and acute central/hemicentral RVOs have been classified into three groups: 1) the venous occlusion precedes the ocular hypertension/glaucoma causing neovascular glaucoma and secondary angle-closure glaucoma without rubeosis; 2) the ocular hypertension and the glaucoma precede the venous occlusion and favor its appearance (ocular hypertension, primary angle-closure, primary angle-closure glaucoma, and open angle glaucomas); and 3) the venous occlusion and the ocular hypertension/glaucoma are mostly age dependent appearances due to common vascular and collagen alterations, lacking a causal connection between the 2 conditions.

Iris surface features and anterior chamber depth in Chinese adolescents

Background

We aim to determine the association of iris surface features including crypts, color and contraction furrows with anterior chamber depth (ACD) in a school-based sample of Chinese teenagers.

Methods

Totally, 2346 students aged 13 to 14 years in Mojiang located in the Southwestern part of China contributed to this analysis. Iris surface features were graded based on standardized slit-lamp photographs. Ocular biometric parameters including ACD were measured using an IOL Master. Generalized estimating equation was incorporated in the linear regression models to assess the relationship between iris surface features and ACD.

Results

A significant trend of increasing ACDs with more contraction furrows were observed. On average, the mean ACD was 3.03 mm in participants with contraction furrows of grade 1 while it was 3.10 mm in those with grade 3 (mean difference, 0.07 mm, P = 0.01). Adjusting for other potential confounders such as gender, height and weight did not significantly changed the associations. Compared with individuals with contraction furrows of grade 1, those with grade 3 had a greater ACD of 0.06 mm (95% confidence interval: 0.01, 0.11) in multivariate-adjusted model. There were no significant relationships between ACD and iris crypts or color. (P > 0.10).

Conclusions

More iris contraction furrows are associated with greater ACDs while the association with iris color and crypts were not significant.

Primary angle closure and primary angle closure glaucoma in retinal vein occlusion

PURPOSE

To investigate the frequency of primary angle closure (PAC) and primary angle closure glaucoma (PACG) in patients with retinal vein occlusion (RVO) based on a hospital population.

METHODS

A total of 375 consecutive cases newly diagnosed with RVO by fluorescein fundus angiography at a single eye centre in Peking were reviewed. Gonioscopy was performed in all patients. Glaucoma was diagnosed according to the criteria of the International Society of Geographical and Epidemiological Ophthalmology. Retinal vein occlusion was classified as central retinal vein occlusion (CRVO), hemicentral retinal vein occlusion (HRVO), or branch retinal vein occlusion (BRVO), and as arteriovenous crossing RVO (AV-RVO), optic cup RVO (OC-RVO), optic nerve RVO without optical nerve head swelling (NONHS-RVO), or RVO with optical nerve head swelling (ONHS-RVO) based on the site of venous occlusion. Percentage of PAC or PACG for each type of RVO were calculated.

RESULTS

PACG had a frequency of 4.1% [95% confidence interval (CI) 2.2-6.9%] in 317 RVO patients [5.3% (95% CI 2.0-11.2%) in CRVO, 8.8% (95% CI 1.9-23.7%) in HRVO, and 1.9% (95% CI 0.4-5.4%) in BRVO]. Primary angle closure (PAC) had a frequency of 2.9% (95% CI 1.4-5.5%) in RVO. PAC/PACG had a frequency of 11.5% (95% CI 6.3-18.9%) in CRVO, 8.8% (95% CI 1.9-23.7%) in HRVO and 3.1% (95% CI 1.0-7.1%) in BRVO. PAC/PACG was significantly more prevalent in NONHS-RVO [18.9% (95% CI 9.4-32.0%)] than in ONHS-RVO [6.5% (95% CI 2.1-14.5%)], AV-RVO [3.1% (95% CI 0.9-7.8%)], and OC-RVO [2.3% (95% CI 0.1-12.3%)].

CONCLUSION

The overall frequency of PAC/PACG was much higher in patients with RVO (especially CRVO) than that in the general population. Eyes with PAC/PACG may undergo mechanical changes in the lamina cribrosa of the optic disc, resulting in RVO. Angle-closure conditions should be borne in mind when investigating Chinese patients with RVO.