Astereognosis as a presenting symptom in cervical meningioma.

Three unusual cases with astereognosis caused by cervical meningioma are presented. Astereognosis of subcortical origin has been reported several times. According to these reports, the causative lesion was confined to the area extending between the lower brain stem and the fourth cervical vertebra, thus suggesting that a sensory centre for stereognosis could be confined within these well defined anatomical limits, and that therefore a lesion in this area could lead to astereognosis. It is assumed in this paper that the lesion involves the sensory system of the Nucleus Cervicalis Lateralis. Fibres from the spinothalamic tract, a specialized sensory pathway, ascend from the palms of the hands to this nucleus. From this nucleus arise fibres which decussate and reach the Ventral Posterolateral Nucleus of the thalamus. It is likely that a lesion of the nucleus itself or its related sensory tracts may cause astereognosis.