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Updated: May 26, 2026
05:02
Establishment of Acute Pontine Infarction in Rats by Electrical Stimulation
Published on: August 27, 2020
Contralateral glossoplegia in a lower pontine infarction
Bon D Ku1, Hak Young Rhee, Sung Sang Yoon
1Department of Neurology, Kwandong University College of Medicine, Goyang, Korea. neurodasan@paran.com
Summary
A stroke in the left pons caused a 65-year-old man's tongue to deviate to the left. This suggests the corticohypoglossal decussation, a nerve pathway, may vary in location just above the pontomedullary junction.
Area of Science:
- Neurology
- Neuroanatomy
- Stroke Medicine
Background:
- Sudden onset neurological deficits like dysarthria, dysphagia, and hemiparesis warrant prompt investigation.
- Pontine lesions are critical causes of complex neurological impairments.
- Understanding the precise neuroanatomy of cranial nerve pathways is essential for localization.
Observation:
- A 65-year-old male presented with acute dysarthria, dysphagia, right hemiparesis, and sensory loss.
- Neurological examination revealed left-sided tongue deviation (glossoplegia).
- Magnetic resonance imaging (MRI) demonstrated an acute infarction in the left ventromedial pons extending to the dorsal pontine tegmentum.
Findings:
- The observed left-sided tongue deviation, despite a left pontine infarct, suggests interruption of a contralateral crossed corticohypoglossal projection.
- This contralateral projection implies the corticohypoglossal decussation may be located superior to the pontomedullary junction.
- The findings point to potential individual variability in the anatomical location of this crucial neural pathway.
Implications:
- This case highlights the importance of considering anatomical variations in neurodiagnostic localization.
- It provides evidence supporting the existence of a decussation of the corticohypoglossal pathway superior to the pontomedullary junction.
- Further research into the variability of the corticohypoglossal tract is needed for improved understanding of brainstem stroke presentations.
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