Visually induced symptoms questionnaire (VISQ): A subjective evaluation method for biomedical effects induced by stereoscopic 3D video.

The purpose of this paper is to establish an easy-to-use questionnaire for subjective evaluations of visually induced motion sickness (VIMS) and visual fatigue caused by stereoscopic 3D (s3D) images. We reviewed previously used questionnaires and extracted 51 important subjective evaluation items from them. We then recruited 251 participants to observe 3D images designed to easily induce sickness or visual fatigue, and we asked them to respond to the 51 items. As a result of exploratory factor analysis, four factors were extracted according to their factor loadings, and the number of items was reduced to 21. Further processing by confirmatory factor analysis led to the selection of 15 items. Comparing mean ratings for each factor before and after item reduction indicated that item reduction did not significantly affect the participant responses. Therefore, the 15-item Visually Induced Symptoms Questionnaire (VISQ), can be used to evaluate VIMS and s3D visual fatigue.

[Correlation between birefringence and histopathologic figures of keratoconus and bullous keratopathy].

PURPOSE: We studied macroscopic pictures with polarizing filter and microscopic pictures of the corneas in keratoconus and bullous keratopathy. METHOD: Among penetrating keratoplasty specimens referred to the National Defense Medical College, we investigated 16 keratoconus and 189 bullous keratopathy specimens. Macrophotographs with polarizing filter and light microscopic photographs (hematoxylene-eosin staining) were investigated. The hyperbolic polarizing pattern, stromal thickness of corneal specimens and number of fibroblast-like cells in the stroma were analyzed. RESULT: Hyperbolic polarizing patterns depended on the number of fibroblast-like cells in the stroma and the thickness of the stroma, but hyperbolic polarizing patterns had no relation with the epithelium or endothelium of the cornea.