Brain sonography insight into the midbrain in myotonic dystrophy type 2

Area of Science:

• Neurology
• Medical Imaging
• Genetics

Background:

• Myotonic dystrophy type 2 (DM2) is a genetic neuromuscular disorder.
• Understanding DM2's neurological manifestations is crucial for patient care.

Purpose of the Study:

• To analyze transcranial sonography (TCS) findings in genetically confirmed DM2 patients.
• To identify potential imaging biomarkers for DM2.

Main Methods:

• Forty DM2 patients and 38 healthy controls (HCs) underwent TCS.
• TCS was performed using the pre-auricular acoustic bone window.

Main Results:

• Substantia nigra hyperechogenicity was observed in 20% of DM2 patients versus 3% of HCs.
• Brainstem raphe (BR) hypoechogenicity was significantly more common in DM2 patients (56% vs. 10%) and associated with fatigue and sleepiness.
• Increased third ventricle diameter was noted in DM2 patients compared to HCs.

Conclusions:

• BR hypoechogenicity in DM2 may indicate potential therapeutic targets, possibly responding to serotonin-reuptake inhibitors.
• TCS identified brain structure alterations not previously detected by MRI in DM2 patients.