Efficacy of Prisms in Neglect Treatment: A Randomized Single Blind Study

Abstract

Objective: Unilateral Spatial Neglect (USN) commonly occurs after lesions in the right hemisphere. This complex syndrome can be defined as a failure to report, respond, or orient to contralateral stimuli. Patients show several symptoms in everyday life, such as eating only on the right side of the plate, or forgetting to look left before crossing the street.Among the different bottom-up treatments, prisms adaptation has found considerable application, producing a high number of scientific papers, even if these are not always consistent in their conclusions.The aim of this randomized single blind study was to verify the efficacy of prisms in improving neglect syndrome when compared to neutral lenses in a group of stroke in patients with neglect.Methods: All patients were randomized into two groups: Experimental Group (EG) and Control Group (CG). The EG was treated with pointing exercises wearing prismatic lenses producing a deviation of the visual field of 10° to the right, while the CG was treated with pointing exercises wearing neutral lenses that did not produce any deviation of the visual field. Both groups were treated for two weeks.We compared with Analysis of Variance the two groups of stroke patients at two different treatment times, at the enrollment time (T0) and after two weeks (T1). Results:We have compared the EG and CG at T0 and T1 time: both groups show a significant improvement in outcome measure. The analysis between groups highlights that this effect can be related to the time rather than to the group of treatment. Conclusion:According to our results we can conclude that pointing with no visible arm is useful in neglect treatment and that prisms produce some further benefits even if the low number of subjects enrolled is still insufficient to give clear evidence in the use of prisms.