Evaluating the effectiveness of localized sub-Tenon's anesthesia in 23-gauge vitreoretinal surgery.

PURPOSE: To evaluate the effectiveness of localized sub-Tenon's anesthesia for pain control during 23-gauge vitreoretinal surgery. METHODS: Eighty patients were randomly divided into two groups as localized sub-Tenon's (group 1, n = 41) and retrobulbar (group 2, n = 39) anesthesia groups. In group 1, a small volume of anesthetic was injected into the sub-Tenon's capsules at the trocar entry sites. The 23-gauge vitreoretinal surgery was performed in all patients. In both groups, the pain levels during the surgical steps were evaluated using the visual analog pain scale. RESULTS: Patients in group 1 experienced less pain than group 2 patients did during placement of the trocars and scleral depression (p = 0.041, p = 0.029). Pain during laser photocoagulation was higher in group 1 (p = 0.008). There was no serious complication due to anesthesia or surgery. CONCLUSION: Localized sub-Tenon's anesthesia is as effective as retrobulbar anesthesia in many steps of vitreoretinal surgery for providing pain control. It can be considered an alternative form of local anesthesia.

Comparison of retinal nerve fibre layer thickness with visual evoked potential and visual field in patients with multiple sclerosis.

BACKGROUND: To evaluate retinal nerve fibre layer thickness and to compare results with visual evoked potentials and visual field in patients with multiple sclerosis. DESIGN: A prospective, case-control study, university hospital setting. PARTICIPANTS: Seventy-three eyes of 37 multiple sclerosis patients and 74 eyes of 37 healthy subjects. METHODS: All patients underwent a complete neurological and ophthalmological examination and peri-papillary retinal nerve fibre layer thickness was evaluated using scanning laser polarimetry (GDx). Furthermore, visual evoked potential and visual field testing were performed. MAIN OUTCOME MEASURES: The χ(2) test, Student's t-test, Mann-Whitney U-test and Pearson's correlation coefficient analysis of the GDx, visual evoked potential and visual field testing parameters. RESULTS: GDx measurements showed significantly more retinal nerve fibre layer damage in the patients than in the control groups. Comparison of the GDx parameters between patients with optic neuritis and non-optic neuritis demonstrated a statistically significant difference in symmetry (P = 0.046) and superior/nasal parameters (P = 0.009). A correlation was found between the number, superior and inferior ratio parameters, and P100 amplitude obtained with visual evoked potential in patients with non-optic neuritis. Additionally, there was a correlation between the number, inferior ratio and superior/nasal parameters, and the mean deviation of visual field in the non-optic neuritis group. CONCLUSIONS: For retinal nerve fibre layer thickness measurements in multiple sclerosis patients, the GDx, along with other techniques, such as visual evoked potential, can be used as a diagnostic and follow-up criterion, particularly in patients without optic neuritis.