Changes of Emotional State of Blind Patients in a Pilot Trial With a Subretinal Implant

Abstract

Purpose:: Participation in first human applications of retinal implants may create psychological stress for blind patients. Underlying unconscious expectations and concerns regarding the outcome of the implantation as well as mental workload generated by novel visual perceptions could cause negative emotional responses.

Methods:: The Brief Symptom Inventory (BSI, 53 items) by Derogatis, a valid brief psychological self-report symptom scale, has been used in order to assess emotional responses to the distress related to study participation. The test was applied before study start at screening and thereafter in weekly intervals and finally before explantation. The sum score for total Global Severity Index (tGSI) was used for evaluation.

Results:: In the first six blind patients participating in the four week pilot trial (see Zrenner et al, ARVO 2006), the BSI showed that study participation was tolerated well concerning participants’ actual emotional states. At screening all subjects (mean 50.33, SD 12.17) were in the normal range of the tGSI. With regard to the individual baseline level five out of six patients showed initial improvement during the first two weeks including surgery and first function tests. The difference at close out visit compared to screening (t-test: mean diff 6.17, SD 8.95; p=0.08) showed a tendency to lower values at the end of trial participation.

Conclusions:: Participants’ emotional processing during study participation with retinal implants is an important aspect. Specifically this may be true for the challenging experimental conditions of first pilot trials. In the first ongoing pilot trial with an active, cable-bound subretinal implant we found that study participation was well tolerated by the first six patients. They rather improved in their emotional balance during study participation than showing signs of increased stress.

Keywords: retina • quality of life • low vision