Heterotopia in Individuals with 22q11.2 Deletion Syndrome.

Area of Science:

• Neuroscience
• Genetics
• Radiology

Background:

• 22q11.2 deletion syndrome is associated with anomalous early brain development.
• Previous MR imaging and neuropathologic studies indicate brain abnormalities in affected individuals.

Purpose of the Study:

• To retrospectively evaluate cerebral abnormalities, specifically gray matter heterotopia, in individuals with 22q11.2 deletion syndrome.
• To correlate observed brain abnormalities with neuropsychiatric impairments in these individuals.

Main Methods:

• Retrospective analysis of MR imaging (3D T1WI and T2*WI) in 75 individuals with 22q11.2 deletion syndrome and 53 controls.
• Assessment of gray matter heterotopia and other morphologic brain abnormalities by three raters.
• Examination of associations between morphologic findings, cognitive performance, and neuropsychiatric conditions.

Main Results:

• White matter heterotopia was the most frequent finding in individuals with 22q11.2 deletion syndrome (29 vs 0 controls, P < .001).
• Other common findings included cavum septi pellucidi/vergae (20 vs 0), periventricular cysts (10 vs 0), and periventricular nodular heterotopia (10 vs 0).
• No significant differences in general cognitive functioning or psychiatric comorbidities were found between individuals with and without these morphologic abnormalities.

Conclusions:

• Findings suggest that white matter heterotopia, cavum septi pellucidi/vergae, and periventricular cysts are indicative of brain development disorders in 22q11.2 deletion syndrome.
• These specific morphologic brain abnormalities were not associated with variations in the psychiatric or cognitive presentation of the syndrome.