Newborn with a lumbar myelomeningocele

Radiograph of lacunar skull in Chiari II malformation — Lateral radiograph of the skull shows a disordered arrangement of the inner table of the skull.

The diagnosis was lacunar skull in a patient with a Chiari II malformation.

Newborn with an abnormal bump in the posterior midline at the skull base

CT of Chiari III malformation — 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.

The diagnosis was Chiari III malformation with an occipital encephalocele.

Newborn with a myelomeningocele

MRI of Chiari II malformation and myelomeningocele — Sagittal T1 MRI without contrast of the brain (left) shows a small posterior fossa with downward cerebellar tonsil herniation and a small fourth ventricle. There is kinking of the spinal cord at the cervico-medullary junction. Sagittal (above right) and axial (below right) T2 MRI without contrast of the spine shows a low-lying conus medullaris with the spinal cord nerve roots terminating in a posteriorly located cerebrospinal fluid filled sac which is not covered by skin at the level of the L5-S1 vertebral bodies.

The diagnosis was Chiari II malformation with a myelomeningocele.

Infant status post myelomeningocele repair

MRI of Chiari II malformation — Sagittal T1 MRI without contrast of the brain shows a small posterior fossa with downward cerebellar tonsil herniation and a small fourth ventricle. There is kinking of the spinal cord at the cervico-medullary junction. There is also agenesis of the body and rostrum of the corpus callosum.

The diagnosis was Chiari II malformation and agenesis of the corpus callosum.

School ager with vomiting at night

CT of Chiari I malformation — Sagittal midline 2D reconstruction of CT without contrast of the brain shows the cerebellar tonsils to be herniating > 5 mm beneath the foramen magnum.

The diagnosis was Chiari I malformation.

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View the illustrated DDX of Chiari malformations.

Newborn with abdominal distension and failure to pass meconium

Gross pathological image of Hirschsprung disease — Gross pathological image of the recto-sigmoid colon shows the dilated proximal portion of sigmoid colon which contained ganglion cells (on the left) separated by a transition zone from the narrowed distal portion of rectum (on the right) which turned out to be aganglionic.

The diagnosis was Hirschsprung disease.

Pediatric Imaging Pearl of the Week

View the illustrated DDX of cerebral vascular malformations.

Infant with heart failure

MRI and MRA and US of intracranial arteriovenous malformation — Axial T2 MRI of the brain (above left) shows large vascular flow voids representing the nidus of the lesion along the right hemisphere of the brain and a dilated sagittal sinus. Sagittal US of the midline of the brain (above right) shows a large vascular structure with mixed arterial and venous flow within it that is compressing and displacing the sagittal sinus beneath it. MR angiogram with contrast of the brain (below left) shows a large nidus of arterial vessels along the right cerebral hemisphere fed primarily by the right middle cerebral artery that rapidly drain into a dilated sagittal sinus on the MR venogram (below right).

The diagnosis was intracranial arteriovenous malformation with arteriovenous fistula.

Toddler who fell out of the top of his bunk bed 3 days ago and is now seizing

CT and MRI of cavernous malformation — Axial (above left) and coronal (above right) CT without contrast of the brain shows a large round high density lesion in the left middle cranial fossa. Axial T1 MRI without contrast of the brain (below left) shows the lesion to have mixed signal intensity while the axial gradient echo MRI (below right) shows a low signal intensity ring around the lesion representing hemosiderin deposition.

The diagnosis was cavernous malformation with subacute and chronic hemorrhage in the left temporal lobe.

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View the illustrated DDX of cerebral vascular malformations.

Newborn with failure to pass meconium and bilious vomiting

Surgical image of Hirschsprung disease — Surgical image shows a transition zone in the terminal ileum with the proximal portion of the small bowel above the transition zone dilated (on the right) and the non dilated distal small bowel (on the left). The frozen biopsies showed no ganglion cells from the rectum all the way up to the terminal ileum.

The diagnosis was total colonic Hirschsprung disease.

Pediatric Imaging Pearl of the Week

View the illustrated DDX of posterior fossa brain tumors.

School ager with double vision

CT of cerebellar astrocytoma — Axial CT with contrast of the brain shows a large heterogeneous cystic and solid mass encompassing the entire right cerebellar hemisphere which is compressing the slit-like fourth ventricle and shifting it to the left, resulting in obstructive hydrocephalus of the third and lateral ventricles.

The diagnosis was cerebellar astrocytoma.

School ager with headaches and behavior changes

MRI of medulloblastoma in the posterior fossa — Axial (above left), sagittal (above middle) and coronal (above right) T1 MRI with contrast of the brain shows a heterogeneously enhancing mass centered in the fourth ventricle which extends into the right cerebellar hemisphere. Axial T2 MRI (below left) shows the mass to be solid and on diffusion weighted imaging (below right) the mass demonstrates diffusion restriction.

The diagnosis was medullobastoma.

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View the illustrated DDX of posterior fossa brain tumors.

Toddler with joint pain, abdominal pain, and a palpable rash

Clinical image of Henoch-Schonlein purpura — Clinical image shows the lower extremities to be covered with purple-colored palpable purpura.

The diagnosis was Henoch–Schonlein purpura.

Pediatric Imaging Pearl of the Week

View the illustrated DDX of spinal canal lesions.

Toddler with back pain and decreased weight bearing

MRI of atypical teratoid rhabdoid tumor (ATRT) of the spine — Sagittal T1 without contrast (left), sagittal T2 (middle) and sagittal T1 with contrast (right) MRI of the lumbar spine shows an extramedullary intradural lesion that is inferior to the conus medullaris and fills the spinal canal from the level of the L1-L3 vertebral bodies. The lesion has heterogenous signal intensity on T2 and heterogenous enhancement with contrast.

The diagnosis was atypical teratoid rhabdoid tumor.

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View the illustrated DDX of spinal canal lesions.

Newborn post op from repair of an anterior abdominal wall defect

Surgical image of gastroschisis — Surgical image shows a prosthetic silo over loops of bowel not encased by a membranous sac that was created by sewing the silo to the fascia on either side of the incision. The silo was then wrapped in cotton gauze and sterile drapes. The patient underwent serial mesh tightening and on day of life eight underwent removal of the silo and final closure of the gastroschisis.

The diagnosis was gastroschisis.

Pediatric Imaging Pearl of the Week

View the illustrated DDX of term infant brain cysts.

Newborn with intracranial cyst on prenatal US

CT of cavum vergae — Axial CT without contrast of the brain show a cystic structure that is a posterior extension of cavum septum pellucidum, posterior to anterior columns of the fornix, and anterior to the splenium of the corpus callosum.

The diagnosis was cavum vergae.

Teenager with headaches

MRI of cavum vellum interpositum — Sagittal (left) and axial (right) T1 MRI without contrast of the brain show a cystic structure between the atria/trigones of the lateral ventricles, behind the foramen of Monro, beneath the columns of the fornices and above the tela choroidea of the 3rd ventricle.

The diagnosis was cavum vellum interpositum.

Infant with macrocephaly

MRI of hemispheric arachnoid cyst — Axial T2 (left) and coronal T1 (right) MRI without contrast of the brain show a large extra-axial cystic structure in the right hemisphere causing significant mass effect to the left.

The diagnosis was arachnoid cyst.