Case report: neuroimaging analysis of pediatric ADHD-related symptoms secondary to hypoxic brain injury

Area of Science:

• Neuroscience
• Pediatric Neurology
• Radiology

Background:

• A pediatric patient presented with symptoms later diagnosed as attention deficit hyperactivity disorder (ADHD).
• The patient had a history of partial internal carotid occlusion and asphyxiation at age two, leading to hypoxic brain injury.

Observation:

• Advanced neuroimaging techniques including diffusion tensor imaging (DTI), positron emission tomography (PET), and quantitative volumetrics (QV) MRI were employed nine years post-incident.
• DTI revealed significantly reduced fractional anisotropy (FA) in key brain regions, exceeding typical ADHD-related changes.
• PET scans showed decreased metabolism in areas not characteristic of ADHD, and QV identified enlarged brain regions, including the amygdala, contrary to ADHD literature.

Findings:

• The patient's neuroimaging data presented distinct patterns inconsistent with primary ADHD.
• Specific reductions in FA and altered metabolic activity were observed in the anterior corpus callosum, internal capsule, hippocampus, orbitofrontal cortex, anterior cingulate, insular cortex, and striatum.
• Enlargement of the amygdala was noted, contrasting with typical ADHD findings.

Implications:

• The unique neuroimaging profile strongly suggests the patient's ADHD symptoms are a sequela of secondary hypoxic brain injury rather than primary heritability.
• This case highlights the importance of considering secondary causes for ADHD-like symptoms, especially with a history of brain insult.
• The findings underscore the utility of advanced neuroimaging in differentiating primary ADHD from ADHD secondary to brain injury.