Brain perfusion abnormalities in Rett syndrome: a qualitative and quantitative SPET study with 99Tc(m)-ECD

Area of Science:

• Neurology
• Pediatrics
• Radiology

Background:

• Rett syndrome is a severe neurodevelopmental disorder affecting only girls.
• It is characterized by progressive neurological decline and intellectual disability.
• Understanding the underlying pathophysiology is crucial for managing the condition.

Purpose of the Study:

• To investigate if abnormal brain blood flow patterns correlate with Rett syndrome manifestations.
• To assess the utility of 99Tc(m)-ethyl-cysteinate-dimer (99Tc[m]-ECD) single photon emission tomography (SPET) in evaluating cerebral perfusion in Rett syndrome.
• To determine if SPET findings can explain the clinical progression of the disease.

Main Methods:

• 12 girls diagnosed with Rett syndrome underwent 99Tc[m]-ECD SPET.
• Global and regional cerebral blood flow was assessed qualitatively and quantitatively.
• Results were compared to an age-matched healthy control group.

Main Results:

• Girls with Rett syndrome exhibited significantly reduced global cerebral perfusion compared to controls.
• This reduction was more pronounced in later stages (Stage IV) of the disease.
• SPET identified hypoperfused brain areas, potentially linked to atrophy, even with normal MRI findings.

Conclusions:

• Reduced cerebral perfusion is a key feature in Rett syndrome, reflecting functional brain disturbances.
• 99Tc[m]-ECD SPET is a sensitive tool for detecting these perfusion deficits.
• These findings support the role of hypoperfusion in the clinical presentation and progression of Rett syndrome.