Presentation
Two months history of chronic vomiting. Ultrasound, abdominal CT and upper GI endoscopy were normal.
Patient Data
Inverted V-shaped lesion involving the posteroinferior surface of the medulla oblongata, eliciting a low signal on T1, high signal on T2, T2*, FLAIR and DWI with mild enhancement well-demonstrated on postcontrast axial T1 fat sat.
Normal appearance of the optic nerves and chiasma as well as the spinal cord.
No other demyelinating lesion seen at infra-or supratentorial level.
Annotated images: the arrows indicate the demyelinating lesion in the area postrema.
Case Discussion
The clinical presentation and the MRI features of demyelinating lesion in the area postrema with no associated neuromyelitis optica, most consistent with an isolated area postrema syndrome (Aquaporin 4 antibodies and MOG-IgGs were negative in this case).
The area postrema is located on the dorsal inferior surface of the medulla oblongata. The specialized ependymal cells in the area postrema detect toxins in the blood and act as a vomit-inducing center.
Area postrema syndrome is usually a demyelinating disorder involving the chemoreceptor trigger zone (area postrema) and considered as one of the core clinical characteristics of neuromyelitis optica spectrum disorder. However, this syndrome has also been rarely reported with other pathologies, such as ischemic stroke, brainstem glioma, and Bickerstaff encephalitis.
Additional contributors:
Dr. R. Bouguelaa, MD, CIM Aures, Batna, Algeria
Dr. MA. Djeradi, Pediatrician, CHU, Batna, Algeria