hemianesthesia
Pronunciation: hem-ee-an-es-THEE-zee-ah
Loss of sensation affecting one half of the body, typically resulting from central nervous system lesions.
Full Definition
Hemianesthesia is a neurological condition characterised by complete or partial loss of sensation on one side of the body, usually following a vertical midline. This sensory deficit commonly results from lesions affecting the thalamus, brainstem, or parietal cortex, particularly the primary somatosensory area. The condition can affect various sensory modalities including touch, temperature, vibration, and proprioception. Unlike peripheral nerve injuries, hemianesthesia typically affects the entire half of the body from head to toe. The pattern and extent of sensory loss provide important localising information about the neuroanatomical site of injury.
Usage
Usage note: Specify affected sensory modalities and any sparing patterns for complete clinical description.
In Context
- "Right-sided hemianesthesia suggested a left thalamic stroke." — Neurological examination findings
- "The patient's hemianesthesia was most pronounced for light touch and temperature sensation." — Sensory testing documentation