Rod and frame test and posture under optokinetic stimulation used to explore two complementary aspects of the visual influence in postural control after stroke

摘要

Highlights ? Visual sensitivity disturbs postural and balance disorders and limits autonomy. ? Visual sensitivity can be defined according to concepts of perception and action. ? The RFT and the OKS detect 2 relevant effects of visual sensitivity. ? Rehabilitation programs could be personalized according to the visual sensitivity. Abstract Background Balance rehabilitation should consider individual comportments according to visual input (VI). Indeed, visual dependence (VD), defined as the predominance given to the VI whatever the circumstances, frequent after stroke it could disturb balance. Because the term VD is a bit restrictive and cannot be deduced from clinical tests, the term visual sensitivity (VS) is preferred here. Hypothesis VI could have different influence depending on the task for a given individual. Methods We retrospectively compared 2 VS tests routinely used: the rod and frame test (RFT) and optokinetic stimulation (OKS). In RFT, VS was defined by a misperception of the visual verticality induced by a tilted frame (VS RFT) and in OKS by tilted sitting posture induced by rotational OKS (VS OKS). We studied the relations between VS RFT and VS OKS. Results We analysed data for 84 patients, mean age 55±10years, 45±30days after stroke. Scores for both tests were correlated with autonomy measured by the functional independence measure (r=?0.3, p=0.01 and r=?0.2, p=0.02). VS OKS score was also correlated with balance measured by the postural assessment scale for stroke (r=?0.3, p=0.03). VS RFT score was not correlated with VS OKS score (p=0.4, r=0.04). Discussion - conclusion A patient may display VS for one test without sensitivity for the other because these tests investigate different neural organisation — perception for RFT or action for OKS. Their relation to balance disorders should be further investigated to build individualized rehabilitation programs.