Behçet Disease

KEY FACTS

TERMINOLOGY

• Chronic, idiopathic relapsing-remitting multisystem

vascular-inflammatory disease characterized by recurrent

orogenital ulcerations and uveitis

○ CNS involved in up to 20-25% of patients

IMAGING

• Best diagnostic clue: T2 hyperintense brainstem lesion in

patient with oral and genital ulcers

○ Midbrain > pons > basal ganglia > thalami > white matter

○ Focal or multifocal lesions

○ May see expansion of involved structures acutely

• T2WI: Hyperintense lesions

• T1WI C+: Patchy enhancement typical

• ↓ N-acetylaspartate (NAA) in acute lesions

○ NAA may normalize when lesions resolve

• May see atrophy of involved structures chronically

TOP DIFFERENTIAL DIAGNOSES

• Gliomatosis cerebri

• Acute disseminated encephalitis

• Primary CNS lymphoma

• Vasculitis

• Multiple sclerosis

CLINICAL ISSUES

• Neurologic deficit (hemiparesis), headache, seizure

common presenting features

○ Other: Recurrent meningoencephalitis

• Young adults, median age: 40 years

DIAGNOSTIC CHECKLIST

• Consider Behçet disease in young adult with brainstem or

deep gray nucleus lesion

• Enhancement pattern may help differentiate Behçet

disease from other etiologies

(Left) Axial FLAIR MR shows

abnormal hyperintensity and

mild expansion of the left

ventral midbrain ﬇ and

patchy hyperintensity in the

right midbrain ſt in this 35-

year-old man with neuroBehçet disease. This chronic,

relapsing idiopathic

multisystem vascular

inflammatory disease is also

characterized by oral and

genital ulcers. (Right) Axial T1

C+ MR in the same patient

shows enhancement of the

large midbrain lesion ﬊.

Imaging typically mimics

neoplasm, vasculitis, and

demyelination.

(Left) Axial FLAIR MR in the

same patient 2 years later

shows resolution of the left

midbrain lesion and

development of a large right

midbrain lesion ſt involving

the cerebral peduncle. A

relapsing-remitting clinical

course is typical. (Right) Axial

T2WI MR shows hyperintensity

in the pons with mild

expansion ﬇ in a young man

with oral ulcers and a clinical

diagnosis of Behçet disease.

Other lesions were present in

the midbrain and basal

ganglia. Thalamic and white

matter involvement is less

common in this disease.

Trauma, and Stroke

Brain: Pathology-Based Diagnoses: Malformations,

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