Cortical Morphology in Patients with Orthostatic Intolerance

Area of Science:

• Neuroimaging
• Neurology
• Human Anatomy

Background:

• Orthostatic intolerance (OI) is a complex condition affecting autonomic nervous system regulation.
• Understanding the neurological basis of OI subtypes is crucial for targeted treatments.

Purpose of the Study:

• To investigate cortical morphology differences in patients with orthostatic hypotension (OH) and postural tachycardia syndrome (POTS) compared to healthy controls.
• To determine if specific subtypes of OI exhibit distinct neuroanatomical alterations.

Main Methods:

• T1-weighted MRI scans of 30 OI patients (22 OH, 8 POTS) and age/sex-matched controls were analyzed using FreeSurfer.
• Cortical thickness, surface area, volume, and curvature were compared between patient groups and controls.

Main Results:

• Patients with OH showed significantly reduced cortical thickness in several right hemisphere regions (medial orbitofrontal, peri-calcarine, post-central, inferior temporal, lateral occipital) and left peri-calcarine cortex compared to controls.
• No significant differences in cortical thickness, surface area, volume, or curvature were found between POTS patients and controls.
• Other cortical morphology measures (surface area, volume, curvatures) did not differ between OH patients and controls.

Conclusions:

• Cortical morphology is significantly altered in orthostatic hypotension but not in postural tachycardia syndrome.
• These findings support the heterogeneity of orthostatic intolerance, indicating distinct pathophysiological mechanisms for OH and POTS.