Assessment of visual space recognition in patients with visual field defects using head mounted display (HMD) system: Case study with severe visual field defect

Abstract

For the quantitative assessment of visual field defects of cerebrovascular patients, we developed a new measurement system that could present various kinds of visual information to the patient. In this system, we use a head mounted display as the display device. The quantitative assessment becomes possible by adding the capability to measure the eye movement and the head movement simultaneously by means of a video apparatus of motion analysis. In our study, we examined the effectiveness of this system by applying it to a patient with serious visual field defects. The visual image of the reduced test paper was presented to the patient, the effect on his/her spatial recognition and eye movement was investigated. The results indicated the increase in the ration of visual search in the reduced side. With the reduced image, the decrease of the angular velocity of eye movement was recognized in the visual search in the defected side. In the motion analysis, the head movement was not observed while the eye movements appeared corresponding to each different conditions. This fact led us to confirm that the patient coped with this kind of test by the eye movement. In this analysis, the effectiveness and the usefulness of the developed system were confirmed that enables us to evaluate the abnormal and compensation movement of the eyes.

A Preliminary Study of the Assessment of Visual Space Recognition in Stroke Patients using New Head Mounted Display (HMD) System with Visual Image Transformation

“…Since the CBS results of USN patients who participated in this study indicated left neglect in ADL, it is plausible, as previously reported by Tanaka et al [17][18][19][20] that this HMD system featuring diverse visual indexes could discern USN symptoms that otherwise would not have been detected through conventional desktop tests. Furthermore, correct response rates were found to be lower for the right side of the sheet (i.e., the unimpaired side) in VFD and USN patients.…”

“…Moreover, USN symptoms not disclosed by the ordinary line cancellation test were found by the HMD system. Eyes and head movement analysis were also added to our HMD system [19,20]. Various reports have described the assessment of the eye movement of left USN patients [21][22][23].…”

Assessment of visual space recognition of patients with unilateral spatial neglect and visual field defects using a head mounted display system

“…The USN patients in this laboratory test presented left spatial neglect in the everyday life according to the CBS score. A new assessment and training for USN with use of a HMD was proposed by Tanaka et al 19 , 20 , 21 ) . There are a few reasons for the decline in the line cancellation rate for the right sheet of the VFD and USN patients.…”

“…USN symptoms not disclosed by the ordinary line cancellation test were found by the HMD system. Eyes and head movement analysis were also added to the HMD system 20 , 21 ) .…”