Isolated inferior rectus palsy as a result of paramedian thalamopeduncularinfarction

The authors present the cases of two patients with isolated inferior rectus muscle paresis presumed to be caused by paramedian thalamopeduncular infar ction that involved supranuclear descending pathways, just before the infer ior rectus subnucleus in one patient, and just before subnucleus or fascicu lar fibers in the other patient. Both patients had no other associated neur ologic dysfunction. The lesions that cause isolated inferior rectus palsy i n these patients are documented by magnetic resonance findings. Although va scular ischemic lesions as the cause of isolated inferior rectus palsy were reported previously, to the authors ' knowledge, it has not been demonstra ted radiologically.