Stereopsis in idiopathic macular hole with special reference to the size of the hole and its effect on stereoacuity.
OBJECTIVE
To identify the characteristics of binocular vision in unilateral idiopathic macular hole (MH) regarding the size of the hole and its effect on stereopsis.


METHODS
Twelve patients with idiopathic MH were tested using the Amsler Grid, Bagolini Striated Glasses, Starlight Test, Titmus Stereotest (the Titmus) and Lang Stereotest (the Lang). The results were analyzed with reference to two parameters: visual acuity and the size of the MH.


RESULTS
The size of the MH in 12 subjects ranged from 0.67 degrees to 2.13 degrees (mean, 1.29 degrees). The MHs caused distorted central vision under binocular conditions. Visual acuities ranged from 0.3 to 0.06. Nine out of the 12 patients (75%) failed the 800 seconds of arc (") with the Titmus, but all 12 patients (100%) demonstrated stereoacuity of 550" to 600" with the Lang.


CONCLUSIONS
The discrepancy of measured stereoacuity between the Titmus and the Lang was hypothesized to be due to the different size of the test charts and their targets and the pattern of the visual deficit. The pass rate of 92% (550") with the Lang is better than rates for other patients with higher visual acuities, such as children with amblyopia (62-70%) or adults undergoing visual screening (67%). In cases of MH, intact overlapped visual field beyond the central 0-2 degrees played an important role in maintaining stereoscopic vision.
Hirai
Toshie
T
Department of Ophthalmology, Nagoya University School of Medicine, Japan. toshieh@med.nagoya.ac.jp
Ito
Yasuki
Y
Terasaki
Hiroko
H
Ito
Mari
M
Sato
Miho
M
Miyake
Yozo
Y
D000368:Aged; D003867:Depth Perception / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012167:Retinal Perforations / Q000503:physiopathology*; D014787:Vision Tests; D015348:Vision, Binocular / Q000502:physiology; D014792:Visual Acuity / Q000502:physiology*