Abstract
Abstract: :
Purpose: To evaluate whether Retinitis Pigmentosa (RP) patients can benefit from the use of a new optoelectronic night-vision device (3MAX). Methods: 3MAX is a photoenhancer which increases the amount of luminance and allows manual adjustment of brightness and contrast. An additional infrared light source may be used at very low light level. 20 consecutive RP patients (12 males and 8 females, age range 9 to 65 years) without other health problems limiting mobility and use of the device were included in the study. 18 presented with a non-syndromic form of RP and 2 with Usher syndrome type II. Best corrected visual acuity, contrast sensitivity, motion and identification performances were tested following a dedicated protocol with and without 3MAX in mesopic and scotopic conditions. Each patient was also asked to fill in a mobility questionnaire based on the 35-item instrument, developed by Turano et al, before and after adequate training with 3MAX. Tolerance of the device was also evaluated. Results: All the patients had decreased visual function under scotopic condition. The majority of them (95%) showed an improvement of visual performance with 3MAX under scotopic condition, while this was not so significant under mesopic condition. The improvement was directly related to residual visual field and visual acuity. The 35-item questionnaire also confirmed an improvement for items in scotopic condition. All the patients but 2 reported some degree of fatigue while using 3MAX and motion sickness induced by the difficulty in evaluating depth of field was common. It decreased with practice. Conclusions: Patients with RP can benefit from 3MAX particularly in scotopic luminance. The device improves visual performances both objectively and subjectively. Training with the device is essential to reduce adverse effects, such as motion sickness. 3MAX seems particularly suited for young patients in the earlier stages of the disease.
Keywords: retinitis • low vision