Strokes occur as a result of interrupted blood supply to the brain either due to a blood vessel rupture or blockage of the vessel. The National Institute of Neurological Disorders and Stroke indicates that there are two forms of stroke: ischemic, which occurs from blockage of a blood vessel supplying the brain, or hemorrhagic, referring to bleeding in or around the brain. Sensory stroke refers to one of the many syndromes suffered after stroke, resulting in persistent numbness, tingling or unpleasant sensations on one or both sides of the body.
Lacunar Infarction
The National Institute of Neurological Disorders and Stroke explains that a lunar infarction is the blockage of a small artery causing tissue death in a deep structure located under the cortex of the brain. The thalamus, which is an area of the brain located in the deeper regions, receives blood flow through a unique set of arteries. According to Harvard Medical School, lacunar strokes happen differently from other forms of stroke because these arteries are smaller and more vulnerable than those of the outer brain regions. Damage to the deeper brain regions can result in the sensory changes experienced in stroke. Sensory stroke from lacunar infarction includes symptoms of facial paralysis, sudden numbness or eye paralysis. Lacunar infarction can cause significant disability, however the prevalence of occurrence is less than that of ischemic stroke.
Cerebral Hemorrhage
The American Stroke Association indicates that hemorrhagic related strokes occur from weakened vessels around the brain causing blood to accumulate at the site and deaden brain tissue. According to a 2000 study in the "American Journal of Neuroradiology," a cerebral hemorrhage can cause a rare occurrence of pure sensory stroke. Study subjects were found to have sensory deficits related to bleeding in focused portions of the brain. Sensory impairments involving distortions of touch and skin sensation reported by study subjects were found through magnetic resonance imaging as resulting from hemorrage in the pontine and thalamic brain regions.
Dejerine Roussy Syndrome
In a small percentage of stroke patients, Dejerine Roussy syndrome can occur. The "Internet Journal of Pain, Symptom Control and Palliative Care" explains that this condition causes various sensory abnormalities including disturbance of temperature discrimination and burning or freezing sensations. This condition is not present in all stroke survivors, however, the study indicates that recurrent damage to the thalamus of the brain is the likely culprit. Perceptual distortion of pain is the primary sensory symptom present in this syndrome and treatment involves stimulating pain receptors.
Additional Factors
Risk of sensory stroke increases with unhealthy lifestyle habits such as smoking and excessive use of alcohol. The National Institute of Neurological Disorders and Stroke further indicates that people with poor eating habits, such as those with a diet high in cholesterol, can also increase the chance of stroke occurrence. Plaque buildup, causing blockage of arterial blood flow is a factor in forming aneurysms in the brain. Rupture of an aneurysm can occur in the deep regions of the brain associated with sensory functions.
References
- Harvard Medical School: Lacunar Stroke
- American Stroke Association: Hemorrhagic Bleeds
- "American Journal of Neuroradiology": Pure Sensory Stroke Caused by a Cerebral Hemorrhage; Shuzo Shintani, Shin Tsuruoka, Tatsuo Shiigai; March 2000
- National Institute of Neurological Disorders and Stroke: Stroke
- Internet Journal of Pain, Symptom Control and Palliative Care: Dejerine Roussy Syndrome: The Role of Methadone in the Treatment of a Central Pain Syndrome; Fred Furgang et al; 2001
