title: Levodopa-carbidopa may improve vision loss in indirect traumatic optic neuropathy.
abstract: To compare the effect of levodopa-carbidopa on the visual outcome of patients with indirect traumatic optic neuropathy (ITON), this randomized, double-blind, placebo-controlled study was conducted on 32 patients with ITON within 6 days after trauma. Patients underwent a complete ocular examination, pattern visual evoked potential (PVEP) testing, and high-resolution orbital computed tomography (CT) scanning. All patients received high-dose intravenous methylprednisolone, and levodopa was also administered to the levodopa group. The main outcome measures were best corrected visual acuity and PVEP results at the last-completed examination. The study was completed on 16 patients in the levodopa group and 10 patients in the placebo group because the others were lost to follow-up. There were no statistically significant differences for age, sex, involved eye, ocular and CT scan findings, pretreatment visual acuity, frequency of recordable PVEPs, and follow-up. In the levodopa group the visual acuity improved significantly after treatment (p = 0.009), but not in the placebo group (p = 0.34). After treatment the visual acuity in the levodopa group was 2.1 ± 2.1, and in the placebo group was 3.9 ± 1.2 (p = 0.008). In those who had visual acuity less than or equal to figure count, significant improvement in visual acuity was observed in the levodopa group (p = 0.03), but not in the placebo group (p = 0.34). However, the final visual acuity in these patients was comparable after treatment (p = 0.21). Nine patients (56.2%) in the levodopa group, and 1 (10%) in the placebo group, experienced improvement in visual acuity (p = 0.02). The frequency of unrecordable PVEPs were comparable in both groups (p = 0.09). Patients treated with levodopa within 6 days of onset of ITON were more likely to experience improvement in visual acuity than those in the placebo group.
authors.affiliation: Department of Ophthalmology, Shiraz University of Medical Sciences, Shiraz, Iran. razeghinejad@yahoo.com
authors.forename: M Reza
authors.initials: MR
authors.lastname: Razeghinejad
authors.forename: Feisal
authors.initials: F
authors.lastname: Rahat
authors.forename: Mohammadhadi
authors.initials: M
authors.lastname: Bagheri
mesh_terms: D000293:Adolescent; D000328:Adult; D001766:Blindness / Q000188:drug therapy*; D002230:Carbidopa / Q000627:therapeutic use*; D016009:Chi-Square Distribution; D002648:Child; D015259:Dopamine Agents / Q000627:therapeutic use; D004311:Double-Blind Method; D004338:Drug Combinations; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use*; D008297:Male; D008775:Methylprednisolone / Q000627:therapeutic use; D008875:Middle Aged; D020221:Optic Nerve Injuries / Q000188:drug therapy*; D016896:Treatment Outcome; D014792:Visual Acuity / Q000187:drug effects*
chemical_list: D015259:Dopamine Agents; D004338:Drug Combinations; D007980:Levodopa; D002230:Carbidopa; D008775:Methylprednisolone