Color vision and macular recovery time in epileptic adolescents treated with valproate and carbamazepine

Abstract

Visual dysfunction has been reported in patients diagnosed with epilepsy. Some of these visual disturbances may be attributable to either the disease process, or the anticonvulsant therapy prescribed to control the seizures. The aims of our study were to evaluate whether color vision and macular function are impaired in epileptic adolescents, to study if the monotherapy with valproic acid (VPA) and carbamazepine (CBZ) can affect color vision and macular function and to determine the possible relationship between color vision, retinal function and antiepileptic drugs (AEDs) dosage and their serum concentrations. We examined 45 (16 male and 29 female, mean age +/- SD, 15.71 +/- 2.01 years) Caucasian epileptic patients suffering from various types of cryptogenic epilepsy before the beginning of therapy and after 1 year of VPA or CBZ monotherapy and 40 sex- and age-matched healthy controls. Color vision was assessed by Farnsworth Munsell (FM) 100-hue test and total error score (TES) was evaluated. This test consists of colored caps: the testee has to arrange the caps according to their colors macular function was assessed by nyctometry evaluating initial recovery time (IRT) and summation method (SM). This test evaluates visual acuity after a period of intense illumination of macula. Analysis of variance was used to evaluate the difference between controls and patients; moreover, Pearson's correlation test have been performed. Before the beginning of therapy, there were no differences in color vision and macular function between controls and epileptic patients. After 1 year, the patients, treated with VPA or CBZ, showed a deficit in FM 100-hue test. At nyctometry, all patients showed no significant variation of macular function between baseline evaluation and second evaluation at end of the follow-up. Our study demonstrates that, in our group of epileptic patients, epilepsy per se does not affect color vision and retinal function. In contrast, after 1 years of therapy with VPA and CBZ these patients showed a deficit in FM 100-hue test although nyctometry evaluation continued to be normal allowing to exclude an impairment in macular function. Further investigations are required to determine the pathophysiological alteration(s) that are at the basis of color perception defects.

Shocking colours - ECT temporarily improves colour perception in a colour-blind patient

“…It has been observed a rare transient adverse effect immediately after ECT [3] and general anaesthesia. Antiepileptic drugs are known to result in visual disturbances, particularly colour vision defects [4].…”

Efficacy of valproic acid for retinitis pigmentosa patients: a pilot study

“… 28 , 29 However, abnormal color visions in epileptic adolescents treated with VPA were reported. 30 , 31 Sisk 7 reported three cases with complications of VPA treatment, two of which had severe decrease in BCVA; the two patients were 8 years and 15 years of age and received 10 mg/kg/d of VPA for 4–5 months. Bhalla et al 8 reported that 12 (39%) of 31 VPA-treated patients reported systemic side effects, of whom nine (29%) discontinued VPA intake due to side effects.…”

Side effects of psychotropic drugs on eye

“…В исследовании A. Verrotti et al нарушения цветовосприятия были выявлены у 13 пациентов (81,25%), принимавших вальпроевую кислоту: у 7 (43,75%) наблюдались отклонения преимущественно в восприятии сине-зеленой части спектра, у 6 (37,5%) -сине-желтой части [38]. В другой работе A. Verrotti et al было показано, что после 1 года терапии данным препаратом сумеречное зрение, по данным никтометрии, сохраняется в пределах нормы [40].…”