Retinal nerve fibre layer thickness is reduced in metabolic syndrome

AIMS

To investigate retinal nerve fibre layer (RNFL) thickness in people with metabolic syndrome (MetS) and healthy controls.

METHODS

A cross-sectional study was performed from March 2014 to January 2016. All participants underwent anthropometric and serological biochemical measurements, ophthalmological examination, and spectral-domain optical coherence tomography (SD-OCT). Individuals with elevated intraocular pressure, glaucoma, diabetic retinopathy and other ocular disorders were excluded. T-test, Chi square and general linear models were used to analyse the data.

RESULTS

In total, 278 eyes from 139 participants were investigated [median (interquartile range) age: 37 (32-43) years]. RNFL thickness was lower in the nasal superior (107.8 ± 19.5μm) and temporal superior (135.7 ± 18.9μm) sectors in MetS group compared with the control group (114.6 ± 22.4 μm, P = 0.013 and 140.7 ± 18.2 μm, P = 0.027, respectively). After multiple adjustments for age, gender and the side of the examined [right (OD)/left (OS)] eye, MetS was independently associated with a lower RFNL thickness in the nasal superior (β = 0.20, P = 0.009) and temporal superior (β = 0.14, P = 0.048) sectors. RNFL thickness was significantly reduced in participants with higher numbers of metabolic abnormalities, independent of age, gender and the side of the examined eye (P = 0.043).

CONCLUSION

Our findings demonstrate that MetS is independently associated with reduced RNFL thickness, suggesting that neurodegeneration is implicated in pathogenesis of MetS.

Lens parameters as predictors of intraocular pressure changes after phacoemulsification

PURPOSE

To evaluate intraocular pressure (IOP) change after cataract surgery in non-glaucomatous eyes with narrow and open angles (OAs) and its relation to novel lens parameters measured by anterior segment optical coherence tomography (AS-OCT).

SETTING

University affiliated hospital, Farabi Eye Hospital, Tehran, Iran.

DESIGN

Prospective interventional case series.

METHODS

In this prospective study, 85 non-glaucomatous eyes underwent phacoemulsification and lens implantation. Thirty-nine eyes had OAs and 46 eyes had narrow angles (NAs). IOP and biometric parameters were measured by AS-OCT preoperatively and 3 months after surgery. Change in IOP and its relation to biometric parameters, including lens vault (LV), anterior vault (AV), defined as the sum of the LV and the ACD, and relative LV (rLV), defined as the ratio of the LV to the AV, were evaluated. The main outcome measure was degree of IOP change after phacoemulsification.

RESULTS

Of the 85 patients included in the analysis, 35 were male and 50 were female with an overall mean age of 62.2 ± 8.9 years. The average IOP reduction was -4.95 ± 2.26 mm Hg, from a preoperative mean of 17.12 ± 2.47 mm Hg, at 3 months after cataract surgery. The amount of IOP reduction was significantly greater in the NA compared with the OA group. In multivariate linear regression analysis, preoperative IOP and AV were significantly associated with IOP decrease (all ≤ 0.03).

CONCLUSION

Cataract surgery results in IOP reduction in both OA and NA eyes. The amount of IOP reduction is related to AV.

Relationship between GDx VCC and Stratus OCT in juvenile glaucoma

PURPOSE

To compare the ability of scanning laser polarimetry (GDx VCC) and optical coherence tomography (OCT) to discriminate eyes with juvenile glaucoma from normal eyes and to assess the relationship between their parameters.

METHODS

A total of 24 glaucomatous eyes of 24 patients and 24 normal eyes were enrolled. The age range of the patient was 11-40 years with a mean age of 25.1+/-8.2 years. Control groups consisted 24 eyes of 24 individuals without glaucoma with a mean age of 33.2+/-8.2 years. All subjects underwent a full ophthalmic examination, automated perimetry, GDx VCC, and OCT. Correlation coefficients between the parameters of OCT and GDx VCC were calculated. We calculated the area under the receiver operating characteristic curve (AROC) for the main parameters of GDx VCC and OCT.

RESULTS

Statistically significant correlations were observed between GDx VCC and OCT parameters. Pearson coefficients ranged from 0.75 for inferior average to 0.86 for nerve fibre indicator (NFI)/average thickness OCT. The greatest AROC parameter in OCT (inferior average: 0.92) had a lower area than that in GDx VCC (NFI: 0.99). There was a significant statistical significance in all visual field, GDx VCC, and OCT variables between two groups (P<0.05).

CONCLUSIONS

Many GDx VCC parameters were significantly correlated with those of the OCT in patients with juvenile glaucoma. Inferior average and NFI had the greatest AROC parameter in OCT and GDx VCC, respectively. NFI had high sensitivity and specificity for the diagnosis of JOAG.