Left side of face numb
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Causes of Left-Sided Facial Numbness
Trigeminal Neuralgia and Pontine Infarction
Trigeminal neuralgia can be a result of a pontine infarction, which affects the ipsilateral trigeminal nerve. This condition can present with numbness, paraesthesia, and sharp, electric shock-like pain on the affected side of the face. A case study of a 57-year-old man revealed that an MRI scan showed a subacute ischemic lesion in the left dorsolateral pons, correlating with the symptoms of facial numbness and pain primarily in the V2 and V3 distribution of the trigeminal nerve.
Sensory Trigeminal Neuropathy
Sensory trigeminal neuropathy can also cause left-sided facial numbness. A 44-year-old woman experienced intermittent burning and numbness over the left side of her face, which became continuous. This was associated with spasms and other neurological symptoms such as double vision and vertigo. Despite extensive testing, including MRI and lumbar puncture, no definitive cause was identified, suggesting a complex neuropathic process.
Stroke and Ischemic Events
Acute ischemic events, such as strokes, are common causes of sudden-onset facial numbness. A 76-year-old man presented with acute left-sided weakness and numbness, including sensory loss in the left face, arm, and leg. His high blood pressure and the acute onset of symptoms pointed towards a cerebrovascular event. Similarly, a 34-year-old woman experienced left-sided facial, arm, and leg numbness, which was evaluated with CT and CT angiography to rule out stroke.
Neurological Disorders and Mass Lesions
Neurological disorders and mass lesions can also present with facial numbness. A 41-year-old woman with decreased vision and diplopia had numbness on the left side of her face, which was initially evaluated with CT and MRI scans. The imaging revealed sinusitis but no other intracranial abnormalities, suggesting a possible peripheral cause. Another case involved a 37-year-old man with left-sided facial numbness and ataxia, where MRI revealed a mass in the left middle cerebellar peduncle, indicating a possible paraneoplastic syndrome.
Autoimmune and Inflammatory Conditions
Autoimmune and inflammatory conditions, such as Neuro-Behçet’s Disease, can also cause facial numbness. A 53-year-old man with a known history of Neuro-Behçet’s Disease presented with numbness on the left side of his body and face. MRI revealed a lesion on the brainstem, consistent with rhombencephalitis, an inflammatory condition affecting the brainstem.
Other Causes
Other less common causes include conditions like Balo concentric sclerosis, a rare demyelinating disease, which presented in a 23-year-old man with acute left-sided numbness. Additionally, facial numbness can be a symptom of systemic conditions, such as in a 51-year-old man who developed numbness in the left side of his chin and tongue, potentially linked to his exposure to raw sewage and subsequent systemic infection.
Conclusion
Left-sided facial numbness can result from a variety of conditions, ranging from trigeminal neuralgia and ischemic strokes to mass lesions and autoimmune diseases. Accurate diagnosis often requires comprehensive neurological examination and imaging studies to identify the underlying cause and guide appropriate treatment.
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