Motion Perimetry in Glaucoma Studies
The nowadays promotion in understanding the base mechanisms of the visual function loss in glaucoma patients looks inspiring.
Motion sensitivity studies in glaucoma patients being done last years support the numerical pathophysiological and psychophysical data in selective and diffuse loss of large optic nerve fibres responsible for the motion and fast flicker information transfer.
It was found (Bosworth CF, Sample PA, Weinreb RN, 1997) the significant difference in motion coherence thresholds in the areas of known visual field loss and areas of known relative field sparing in eyes with primary open angle glaucoma (POAG).
Deficit of motion sensitivity was reported (Joffe KM, Raymond JE, Chrichton A, 1997) in nearly all glaucoma patients and about half of glaucoma suspects (all with normal visual fields as assessed with static perimetry). Interesting that for the foveal stimulus presentations, authors detect the mean motion coherence sensitivity being normal.
Elevated motion perimetry thresholds was shown in patients with ocular hypertension (OHT) in comparison with the control group (Wall M, Jennisch CS, Munden PM, 1997). That was expressed in the idea on motion perimetry identifies nerve fiber bundlelike defects in OHT.
Reduced motion sensitivity and, in addition, poor discrimination of motion direction was detected in patients with glaucoma (Sahraie A, Barbur JL, Edgar DF, Weiskrantz L, 1996).
Those results may appoint on the perimetric type motion test to be more sensitive method to detect visual field abnormalities in early detection of glaucoma than conventional automated perimetry.
The advantages are proposed to be found in the additional investigations on the nonuniformity and anisotropy of the motion sensitivity. In preliminary findings, authors report the nonuniformity in loosing motion sensitivity accross the visual field and outline (slightly different) the superior and nasal parts being most prevalent. The anisotropic character of the human motion vision in the lower half of the visual field (Ohtani Y, Ejima Y, 1997) was described in normals, and their difference in glaucoma patients is believed to be found.
Bosworth CF, Sample PA, Weinreb RN
Motion perception thresholds in areas of glaucomatous visual field loss. Vision Res 1997 Feb 37:3 355-64.
Joffe KM, Raymond JE, Chrichton A.
Motion coherence perimetry in glaucoma and suspected glaucoma. Vision Res, 1997, 37:7, 955-64.
Wall M, Jennisch CS, Munden PM.
Motion perimetry identifies nerve fiber bundlelike defects in ocular hypertension. Arch Ophthalmol, 1997, 115:1, 26-33.
Sahraie A, Barbur JL, Edgar DF, Weiskrantz L.
Motion discrimination of single targets: comparison of preliminary findings in normal subjects and patients with glaucoma. Graefes Arch Clin Exp Ophthalmol, 1996, 234:9, 553-60.
Ohtani Y, Ejima Y.
Anisotropy for direction discrimination in a two-frame apparent motion display. Vision Res, 1997, 37:6, 765-7.
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