nasal encephalocele

Nasal encephaloceles are in most cases a form of neural tube defect particularly common in Southeast Asia. There is herniation of cranial content through a bony defect in the anterior skull base into the nasal area.

The term is variably used but generally encompasses both frontoethmoidal encephaloceles and basal encephaloceles.

Clinical presentation

Nasal encephaloceles usually present at birth with symptoms of obstruction or other complications. It presents as an external swelling on the nose. The swelling is usually soft, with normal overlying skin, and increases in size on coughing/straining. Symptomatic patients usually present with obstruction or rhinorrhea.

Nasal encephaloceles are typically identified in association with a discernible cranial bone defect.

Pathology

Nasal encephaloceles are anterior encephaloceles where meningeal herniation occurs through a midline defect in the floor of the anterior cranial fossa.

Radiographic features

CT

CT is good for delineating bony abnormalities but not for detecting an intracranial component.

MRI

MRI is better for delineating soft tissue details, including any intracranial connection. It also minimizes the level of exposure to ionizing radiation

Treatment and prognosis

When a midline nasal swelling is present, no invasive procedures nor operations are performed until an intracranial connection has been excluded using CT scanning or MRI, due to the risk of meningitis or cerebrospinal fluid leakage.

Differential diagnosis

General imaging differential considerations include other midline nasal region lesions:

• nasal glioma
• nasal dermoid
• hemangioma
• lipoma

Siehe auch:

• Meningoenzephalozele
• orbitale Enzephalozele
• frontoethmoidale Enzephalozele

und weiter:

• midline nasal region lesions