A Pediatric Radiology Textbook and Pediatric Radiology Digital Library
Cephalocele
Etiology: Cephlocele spectrum — Meningocele – Cerebrospinal fluid and leptomeninges herniate — Meningoencephalocele – Cerebrospinal fluid and leptomeninges and brain herniate — Meningohydroencephalocele – Cerebrospinal fluid and leptomeninges and brain and ventricle herniate
Imaging: Occipital – 70%, parietal – 10%, sincipital – 10%, basal – orbital or nasal or sphenoidal – 10%
Imaging of frontonasal cephalocele: — Herniation through nasofrontal suture — Not typically associated with other intracranial anomalies (unlike occipital cephalocele)
Imaging of occipital cephalocele: — Parietal more typical for atretic cephalocele — Typically has involvement of cerebellar or cerebral hemispheres, may involve venous sinuses — Often significant association with intracranial anomalies – Chiari, Dandy-Walker, callosal or migrational anomalies
Imaging of nasal cephalocele: — Contain herniated frontal lobes — Majority are frontonasal, followed by nasoethmoidal, remainder are nasolateral and may herniate into the orbits — Naming convention for cephaloceles: roof is first named item and floor is second named item — Occasionally transsphenoidal encephaloceles may present in nasal cavity — Brain herniates into persistent dural diverticulum — Prenasal space has not been obliterated and is often considerably widened — Dura and brain herniate anteroinferiorly with nasal bone as roof of sac and cartilage of nasal capsule (ethmoids) as floor
Imaging of nasoethomoidal cephalocele: — Brain herniates into persistent dural diverticulum — Prenasal space persists – often considerably widened — Dura and brain herniate anteroinferiorly with nasal bone as roof of sac and cartilage of nasal capsule (ethmoids as floor)
Imaging of frontal ethmoidal cephalocele: — Via patent foramen cecum — Polyp, nasal mass, or lump on nose in child, must rule out a cephalocele, especially if recurrent meningitis, also can be seen in adult if prior trauma or surgery — Associated CNS anomalies in anterior cephaloceles: lipomas, schizencehaly or holoprosencephaly
DDX:
Complications: Cerebrospinal fluid leak
Treatment: Surgical
Clinical: Cerebellar encephalocele = Chiari III
Radiology Cases of Frontonasal Cephalocele
Sagittal (left) and axial (right) T2 MRI without contrast of the brain shows herniation of the frontal lobes of the brain through the nasofrontal suture.
Clinical Cases of Frontonasal Cephalocele
Clinical images show a large mass in the midline of the face which is enlarging the nose.
Radiology Cases of Parietal Cephalocele
Axial CT without contrast of the brain shows in the left parietal region a low density cystic lesion that has a small amount of brain tissue within it laterally.
Radiology Cases of Occipital Cephalocele
Axial CT without contrast of the skull (above left and below left) shows a large primarily low density soft tissue mass in the midline of the posterior skull extruding through a large defect in the posterior skull (above right). Axial T2 MRI of the brain (below right) shows the mass contains a thin amount of neural tissue.Axial CT without contrast of the cervical spine shows a defect in the posterior skull at the craniocervical junction with cerebellar tissue herniating posteriorly through it.Lateral radiograph of the skull shows a large round soft tissue mass arising from the base of the skull.
Clinical Cases of Occipital Cephalocele
Clinical image shows a primarily skin covered lesion herniating through a defect in the posterior skull that contains neural tissue.
