Correlation Between Ischemic Index of Retinal Vein Occlusion and Oxygen Saturation in Retinal Vessels.

PURPOSE: To evaluate the relationship between the ischemic index and the oxygen saturation in retinal vessels in patients with retinal vein occlusion. DESIGN: Prospective, cross-sectional study. METHODS: We performed a prospective study. The cohort consisted of 43 eyes of 43 patients with retinal vein occlusions (RVO), 23 of whom had central retinal vein occlusions (CRVO) and 20 who had branch retinal vein occlusions (BRVO). We evaluated the retinal vessel saturation using an automatic retinal oximetry device. The retinal ischemic index (ISI) was determined using ultra-widefield fluorescein angiography. RESULTS: Mean arterial saturation (±SD) was 100% ± 11%, mean vein saturation was 52% ±13%, and mean A-V difference was 48% ± 16% in eyes with BRVO. The average ISI in the same group was 0.48 (range 0-1). There was no statistically significant correlation between the retinal ischemic index and retinal saturation in the BRVO group. The affected eye in the CRVO group had a mean arterial saturation of 101% ± 6%, vein saturation of 44% ± 11 % and A-V difference of 58% ± 10%. The average ISI in the CRVO group was 0.54 (range 0-1). A statistically significant negative correlation between ISI and vein saturation was found in the CRVO group (r = -0.686; P =.0003). A significant positive correlation between ISI and the A-V difference was found in the CRVO group (r = 0.893; P <.0001). CONCLUSIONS: Oxygen saturation in the retinal vein and the arteriovenous difference correlated with the ischemic index in CRVO patients. No correlation was found for BRVO patients.

Migration of emboli in the retinal artery: case report.

Branch retinal artery occlusion (BRAO) is a prevalent vascular occlusive disorder of the eye. In transient BRAO, an embolus temporarily blocks the vessel and then moves on resulting in recovery of blood circulation. In this case, we have documented migration of the embolus with recovery of perfusion of the retina and improvement of visual acuity in a patient with transient BRAO. Early diagnosis and fast action are important in the case of patients with retinal artery occlusion.

The natural evolution of idiophatic epimacular membrane.

BACKGROUND AND AIMS: Epiretinal membrane (ERM) refers to a semi-translucent tissue layer found on the inner surface of the retina especially in older people. Surgical treatment remains controversial, optimal timing for such treatment is difficult to determine and data on the natural evolution of this disorder are limited. In this study we evaluated the natural course of idiopathic epimacular membrane in 49 patients (53 eyes). MATERIALS AND METHODS: Retrospective evaluation of a group of 49 patients (53 eyes) with idiopathic epimacular membrane confirmed by biomicroscopy, photography and optical coherence tomography (OCT). RESULTS: Patient age ranged from 51-85 years (median 72). The average follow-up was 21.3 months (± 14). Between the initial and final best corrected visual acuity (BCVA) there was no statistically significant difference although there was a significant tendency to decrease in BCVA (Spearman P=0.05) during the follow-up. Initial BCVA correlated with initial central retinal thickness (CRT), final CRT, final volume, and age. The final BCVA significantly correlated with all parameters measured. CONCLUSION: BCVA during follow-up tended to decrease: difference of starting BCVA and final BCVA values depending on the time of monitoring is significant. This we attribute to a slow gradual progression of macular changes. But, initial and final BCVA measurements were not substantially different at the end. Thus, in the absence of any clear signs of ERM progression, we can safely postpone the decision whether to perform PPV.