Radial Optic Neurotomy in Central Retinal Vein Occlusion Does Not Influence Ocular Hemodynamics

Abstract

Purpose: Radial optic neurotomy (RON) is used for the treatment of central retinal vein occlusion. Its effects on visual acuity differ substantially between patients. Our study aims to evaluate if RON has an impact on ocular microcirculation and if analysis of ocular microcirculation might serve as a predictor for surgical success. Procedures: A complete ophthalmologic examination including color Doppler imaging of the retrobulbar vessels was performed before and 2–4 months after RON in 12 patients. Results: Mean visual acuity was 0.09 ± 0.03 prior to and 0.24 ± 0.12 after RON. Visual acuity improved in 7 (+3.5 ± 0.9 lines), was stable in 3 (±0 lines) and worsened in 2 cases (–6 and –2 lines). Doppler parameters were not affected by RON, and no correlations between visual acuity and perfusion parameters were found. Conclusions: Our data indicate that RON does not influence ocular microcirculation. None of the assessed hemodynamic parameters appears to be a predictor for surgical success.

Retinal Vessel Oxygen Saturation Increases After Vitrectomy

“…29 Other, more controversial surgical procedures like radial optic neurotomy and arteriovenous sheathotomy have had less success in improving ocular perfusion and clinical outcomes, and it is possible that it is the removal of the vitreous rather than these additional surgical manipulations that benefits the patient. [30][31][32] The strengths of our study include a relatively large cohort of subject undergoing surgery, as well as the standardized assessments of Oxymap system parameters as well as systemic covariates. As discussed earlier, our method of analysis has good reliability and repeatability.…”

Central Retinal Vein Occlusion

“…All the available evidence shows that by the time a patient develops visual symptoms, the central retinal vein is completely thrombosed. The hypothesized "decompression" cannot open a central retinal vein completely closed by an organized thrombus to establish or improve blood fl ow in it, as shown by Friberg et al [ 401 ] and Skevas et al [ 402 ]. 4.…”

Behandlung des retinalen Venenverschlusses – Welche Rolle spielt die Vitrektomie heute noch?

“…In einem etablierten Simulationsmodell errechneten Friberg und Kollegen eine maximale venöse Füllungszunahme zwischen 1-5 %, weshalb die RON als nicht wirksam erachtet wurde [21]. In 3 unabhängigen Untersuchungen des okulären Blutflusses mittels Farbdopplersonografie wurde ebenfalls keine Veränderung der Mikrozirkulation nach RON bemerkt [22][23][24]. Es wurde auch, ähnlich der Kurzschlusstheorie nach chorioretinaler Anastomose, der günstige Einfluss von Umgehungskreisläufen an der Einstichstelle postuliert [25][26][27].…”