Cranial nerve involvement in Charcot-Marie-Tooth Disease

Area of Science:

• Neurology
• Medical Imaging

Background:

• Charcot-Marie-Tooth Disease (CMT) is a rare neuromuscular disorder with diagnostic challenges due to varied presentations.
• Magnetic Resonance (MR) and Computed Tomography (CT) imaging are increasingly utilized for evaluating disease extent in CMT.

Observation:

• A 27-year-old female with a history of polio presented with necrotizing pneumonia, later showing extremity atrophy, sensory loss, and pes cavus.
• MRI revealed enlarged, enhancing trigeminal nerves and spinal nerve roots; CT showed skull base foramina widening.
• Electromyography confirmed significant motor and sensory nerve dysfunction.

Findings:

• The case highlights infrequent cranial nerve involvement in CMT 1A, specifically the trigeminal and facial nerves, despite the absence of related symptoms like trigeminal neuralgia.
• Imaging demonstrated smooth, symmetric enlargement and mild enhancement of distal spinal nerve roots and cauda equina.
• No correlation was observed between cranial nerve abnormalities and clinical symptoms in this patient.

Implications:

• This case underscores the diverse clinical spectrum of CMT and the importance of advanced imaging in diagnosis.
• Distinguishing CMT 1A from other forms of Hereditary Motor and Sensory Neuropathy (HMSN) relies on a comprehensive assessment of clinical features.
• Cranial nerve involvement in CMT, while uncommon, can manifest subtly on imaging without corresponding clinical deficits.