An 80-year-old right-handed man presented with reaching disability. When fixing his gaze centrally, his reach to a target in the left visual field with his left leg and arm deviated from it, although his visual field was intact. The deviation increased according to the eccentricity of the target (Picture 1). However, there was no deviation when he was able to move his gaze freely (Picture 2). These findings were consistent with unilateral optic ataxia (UOA) (1). Magnetic resonance imaging revealed a hemorrhagic lesion in the right superior parietal lobule and intraparietal sulcus (Picture 3, arrows), regions thought to be responsible for UOA (1). To date, only one case of UOA in the leg has been reported with brain images (2). That case was due to posthypoxic encephalopathy. Our report is thus the first to show that UOA can occur in the lower limb with a lesion restricted to two areas. Since the superior parietal lobule and intraparietal sulcus have overlapping representations of the upper and lower limbs (2), it is likely that other cases of UOA in the lower limb may be present.
Picture 1.
Picture 2.
Picture 3.
The authors state that they have no Conflict of Interest (COI).
References
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