[Tomographic appearance and etiologies of epimacular membranes in Cotonou]

PURPOSE

To study the tomographic appearance and etiologies of epimacular membranes in Cotonou.

PATIENTS, MATERIALS AND METHODS

This was a descriptive, analytical study with retrospective data collection. It took place at the Cotonou Retinal Testing Center and included all patients who underwent macular OCT testing between January 1, 2016 and June 30, 2018.

RESULTS

Of the 604 subjects examined, 32 patients (5.3%) exhibited an epimacular membrane. Epimacular membrane in combination with posterior vitreous detachment and contraction accounted for 44.74% of cases. 42.31% of the fellow eyes had developed a posterior vitreous detachment. The majority of the membranes were idiopathic. Proliferative diabetic retinopathy and posterior uveitis were the main risk factors for secondary membranes.

CONCLUSION

Epimacular membrane is a potentially blinding condition. The risk of bilateral involvement is significant, and patient access to OCT remains a concern in developing countries.

Surgery for Idiopathic Epimacular Membrane: Morpho-Functional Outcomes Based on the Preoperative Macular Integrity of the Photoreceptoral Junction. A Prospective Pilot Study

INTRODUCTION

This study aimed to evaluate whether the preoperative integrity of the inner segment (IS) and outer segment (OS) photoreceptoral junction may influence the postoperative visual acuity, the macular morphology [assessed by spectral domain optical coherence tomography (SD-OCT)], and macular function (evaluated by multifocal electroretinogram, mfERG) in patients with idiopathic epimacular membrane (EMM) followed up for 6 months.

METHODS

In this observational prospective study, 18 patients with EMM (mean age 72.5 ± 6.87 years) were enrolled. They were divided into two groups according to the preoperative integrity of the SD-OCT IS/OS junction: the EMM-I group with an intact IS/OS junction (11 patients, mean age 72.75 ± 3.49 years, providing 11 eyes) and the EMM-D group with a disrupted IS/OS junction (7 patients, mean age 70.86 ± 10.79 years, providing 7 eyes). For each enrolled patient, visual acuity (VA), mfERG, and SD-OCT were assessed at baseline (preoperative) and after 1, 3, and 6 months of follow-up after surgical treatment for EMM (pars plana vitrectomy with EMM removal and internal limiting membrane peeling).

RESULTS

During the whole follow-up, VA was significantly increased in EMM-I eyes and unmodified in EMM-D eyes. In both groups, mfERG responses were not significantly different and not related to VA differences. In EMM-I eyes a significant reduction of central retinal thickness (CRT) was observed; however, it was not correlated with VA changes. In EMM-D eyes CTR was not significantly reduced, whereas macular volume was significantly reduced. These changes were significantly related to the corresponding differences in VA.

CONCLUSIONS

Our results suggest that the preoperative evaluation of the integrity of the IS/OS junction is relevant for postoperative outcomes. The recovery in VA was higher in EMM-I eyes than in EMM-D eyes. Postoperative recovery was not associated with morphology of the outer retina (photoreceptor and outer nuclear layer) and the function of preganglionic elements.

Topical prostaglandin analogues and development of epiretinal membrane

OBJECTIVES

To determine whether patients with glaucoma and epiretinal membrane (ERM) use a greater proportion of prostaglandin analogues (PA) than a control group of patients with glaucoma without ERM.

METHOD

A retrospective study of cases and controls was conducted in order to determine whether patients with glaucoma and ERM used a greater proportion of PA than a control group of patients with glaucoma without ERM. The diagnosis of de ERM was made by clinical examination and optical coherence tomography.

RESULTS

The mean age of the cases was 77 years (SD: 8.68; 95% CI: 74.3-79.4), compared to the controls with 63 years (SD: 16.6; 95% CI: 70.1-78.5). The cases included 50% (n=26) men and 50% women (n=26), whereas in the controls 25.4% (n=16) of the cases were men and 74.6% (n=47) women. PA treatment was used in 59.6% (n=31) and 60.3% (n=38) of the cases and controls, respectively. There was no statistically significant difference in PA use between the 2groups (P=.939).

CONCLUSIONS

In this study, an association between the use of AP and the development of ERM could not be demonstrated.

[Prognostic factors in uveitis]

PURPOSE

To evaluate prognostic factors of vision loss among patients with uveitis.

MATERIAL AND METHODS

This descriptive and retrospective study included all patients diagnosed with uveitis who were seen at the teaching hospital of Rabat, Morocco, over a 5-year period. Information regarding demographic data, uveitis type, bilaterality of the disease, etiology and complications were gathered from patients' records. Statistical analysis was performed using SPSS software.

RESULTS

One hundred and thirty-nine eyes of 89 patients were included. There were 60.7 % men and 39.3 % women. The mean age (years) was 31.1±16.8. Median follow-up was 11 months. Median visual acuity (logMAR) on admission was 1.7 [0.7-2] and 1 [0.4-1.7] on the last visit (P<0.001). Fifty-nine percent of eyes had final visual acuity (VA) equal to or less than 1/10. Panuveitis (85.4 %) and posterior uveitis (72.7 %) were responsible for final VA equal to or less than 1/10 (P<0.001). Cataract, posterior synechiae, vitreous opacities, epimacular membrane (ERM) and cystoid macular edema (CME) were the most frequent complications. Using multivariate logistic regression, the prognostic factors associated with severe vision loss were the type of uveitis (posterior and panuveitis), CME, ERM, macular scarring and optic atrophy (P<0.05).

CONCLUSION

Although this study included a limited number of subjects, the results showed that final VA was equal or less than 1/10 in 59 % of eyes diagnosed with uveitis and was associated with risk factors including posterior segment involvement (panuveitis and posterior uveitis), CME and ERM.

Assessment of macular function, structure and predictive value of pattern electroretinogram parameters for postoperative visual acuity in patients with idiopathic epimacular membrane

Purpose

To evaluate macular function and structure before and after epimacular membrane surgery and to estimate the usefulness of pattern ERG test parameters in predicting the postoperative visual acuity.

Methods

We evaluated 32 eyes of 32 patients (mean age 70.8 ± 6.7 years) before and 12 months after successful 25G pars plana vitrectomy with epimacular membrane removal and internal limiting membrane peeling. Distance best-corrected visual acuity (DBCVA—logMAR), foveal thickness (optical coherence tomography—OCT) and macular function [pattern electroretinogram—PERG (ISCEV standard): amplitudes (A) of P50- and N95-waves, implicit time (IT) of P50-wave] were assessed. To estimate the differences between the mean values of considered characteristics, the t test or Wilcoxon matched pair test was used. Correlation between preoperative data of PERG and preoperative and final DBCVA were investigated using Pearson correlation analysis. A receiver operating characteristic curve was constructed to obtain a cutoff value allowing prediction of visual prognosis. We tried to obtain the P50 and N95 amplitudes cutoff value in prediction of good visual outcome (DBCVA of 0.3 or less).

Results

Twelve months after surgery, mean of DBCVA significantly increased in comparison with preoperative value (0.31 ± 0.12 vs. 0.6 ± 0.15; p < 0.001) and 23/32 eyes (72 %) achieved visual improvement of two and more Snellen lines. In OCT test, the significant reduction in foveal thickness mean (313.34 ± 47.01 vs. 509.03 ± 93.88 µm; p < 0.001) was obtained. In PERG test, the significant increase in the mean amplitudes of P50- (AP50) and N95 (AN95)-waves as well as significant decrease in the mean implicit time (IT) of P50-wave were achieved (AP50: 3.41 ± 1.48 vs. 2.38 ± 1.23 µV; p < 0.001; AN95: 5.46 ± 1.72 vs. 3.75 ± 1.48 µV; p < 0.001; IT P50: 55.00 ± 3.60 vs. 56.75 ± 5.78 ms; p < 0.001). Twelve months postoperatively, DBCVA was significantly correlated with preoperative IT P50 (r = 0.39; p = 0.027), AP50 (r = −0.68; p < 0.001) and AN95 (r = −0.73; p < 0.001).

Conclusion

Removal of idiopathic epimacular membranes with internal limiting membrane peeling not only provided increase in visual acuity and reduction in foveal thickness but also caused improvement of innermost retinal layer function in macular region. Pattern ERG test might be a valuable tool in predicting the postoperative visual acuity.

[Spontaneous separation of epiretinal membrane: Reports of 3 cases]

PURPOSE

Idiopathic epiretinal membranes most commonly develop in patients over 50 years of age. Posterior vitreous detachment seems to play a role in their formation. Epiretinal membranes are uncommon in young subjects. Surgical intervention is indicated in eyes with true functional symptoms and loss of visual acuity.

METHOD

We report 3 cases with spontaneous separation of epiretinal membranes imaged by Optical Coherence Tomography.

RESULTS

All patients reported improvement in functional symptoms after spontaneous separation of the epiretinal membrane. Anatomic recovery with reappearance of the foveolar depression was observed on Optical Coherence Tomography.

CONCLUSION

A longer period of observation may be indicated in young patients with epiretinal membrane, due to the higher rate of spontaneous separation.