Newborn with a posterior fossa cyst on prenatal ultrasound

MRI of mega cisterna magna — Sagittal (above left), coronal (above right), and axial (below) T1 MRI without contrast of the brain shows a prominent retrocerebellar cerebrospinal fluid space (the cisterna magna) with a normal vermis, normal 4th ventricle, and normal cerebellar hemispheres.

The diagnosis was mega cisterna magna.

Preschooler with new onset diabetes insipidus

MRI of Langerhans cell histiocytosis of the pituitary — Sagittal T1 MRI without contrast (above left) of the brain shows absence of the posterior pituitary bright spot. Sagittal (above right) and coronal T1 with contrast (below left) show a thick and enhancing pituitary stalk. Axial T1 with contrast (below right) again shows the thick enhancing pituitary stalk and enhancing lesions in both sphenoid wings and in the left orbit.

The diagnosis was Langerhans cell histiocytosis of the pituitary and Langerhans cell histiocytosis of the orbit.

Toddler with left orbital swelling

CT and MRI of Langerhans cell histiocytosis of the orbit — Coronal CT with contrast of the orbits in bone (above left) and soft tissue (above right) windows show bony destruction in the superolateral aspect of the orbit caused by a soft tissue mass. Coronal T1 MRI without (below left) and with contrast (below right) of the orbits better show the soft tissue mass superolateral to the left orbit which enhances avidly.

The diagnosis was Langerhans cell histiocytosis of the orbit.

Toddler with a genetic syndrome undergoing screening neuroimaging

MRI of hamartoma of the tuber cinereum / hypothalamic hamartoma — Sagittal T2 (above), T1 without contrast (below left) and T1 MRI with contrast (below right) of the brain show a suprasellar mass that is solid and heterogenous which is isointense on T1 and T2 and is nonenhancing.

The diagnosis was hamartoma of the tuber cinereum.

Teenager with first time seizure

MRI of dysembryoplastic neuroepithelial tumor / DNET — Axial T1 without contrast (above left), T2 (above right) and T1 with contrast (below left) MRI of the brain show a round heterogenous lesion in the medial aspect of the left temporal lobe that appears to extend into the cortex, has a small amount of surrounding edema, and does not enhance. On gradient echo (below right) there is some hemosiderin staining in the lesion but no hemosiderin ring around it.

The diagnosis was dysembryoplastic neuroepithelial tumor.

Teenager with left leukocoria

CT of Coat disease — Axial CT without contrast of the orbits (above left) shows increased density in the left vitreous humor when compared to the right. Axial FLAIR MRI of the orbits (above right) shows the vitreous humor to have high signal intensity which is isointense on T1 MRI without contrast (below left) which was felt to be consistent with proteinaceous material or hemorrhage. Axial T1 with contrast (below right) shows wispy enhancement lateral to the left globe due to retinal detachment.

The diagnosis was Coat disease.

Infant with increasing head circumference

MRI of choroid plexus papilloma — Axial (above left), coronal (above right) and sagittal (below) T1 MRI with contrast of the brain shows an avidly enhancing round mass that has a frond-like pattern in the third ventricle causing marked dilation of the lateral and third ventricles.

The diagnosis was choroid plexus papilloma.

Toddler who was sleepy after a fall

CT and MRI of choroid plexus carcinoma — Axial CT without contrast of the brain (above left) shows a large high density mass that contains a few punctate calcifications in the trigone of the right lateral ventricle that is causing midline shift to the left. Axial T2 MRI (above left) of the brain shows the mass to surrounded by edema and to be causing some transependymal flow of cerebrospinal fluid. Axial (below left) and coronal (below right) T1 MRI with contrast show homogenous enhancement of the mass. A separate enhancing nodule is also noted in the left temporal lobe in the region of the left Sylvian fissure.

The diagnosis was choroid plexus carcinoma.

Newborn with myelomeningocele

MR of cavum septum pellucidum — Axial FLAIR (left) and coronal T1 MRI without contrast of the brain show an oval-shaped CSF space between the leaflets of the septum pellucidum in the center of the brain.

The diagnosis was cavum septum pellucidum.

Infant with left parietal soft tissue swelling

3D CT of intraparietal accessory skull suture — 3D reconstruction of a CT without contrast of the brain shows a lucency arising from the left lambdoid suture anteriorly and curving anteriorly that has a zig zag course through the parietal bone.

The diagnosis was an intraparietal accessory skull suture.

Infant with a bump in the left occiput

3D CT of accessory skull suture — 3D reconstruction of a CT without contrast of the brain shows a lucency arising from the left lambdoid suture inferiorly and curving to the left that has a zig zag pattern and seems to interdigitate within the skull. Soft tissue windows showed no associated soft tissue swelling.

The diagnosis was accessory skull suture.

Newborn with dehydration

US CT MRI of superior sagittal sinus thrombosis / SSST — Coronal spectral (upper left) and color (upper right) doppler US of the superior sagittal sinus shows decreased flow within it. Axial CT without contrast of the brain (below left) shows increased density in the superior sagittal sinus. Sagittal T1 MRI without contrast of the brain (below right) shows focal areas of increased signal intensity in the superior sagittal sinus.

The diagnosis was partial dural venous sinus thrombosis of the superior sagittal sinus.

Preschooler not moving their lower extremities after a MVA

spinal cord injury without radiological abnormality / SCIWORA — Sagittal CT without contrast of the spine (left) shows no fractures. Sagittal T2 (middle) and STIR (right) MRI without contrast of the cervical spine shows a round high signal intensity lesion in the spinal cord at T1-T2.

The diagnosis was spinal cord hemorrhage resulting in spinal cord injury without radiological abnormality.

Toddler with fever, dysphagia, and neck pain

CT of retropharyngeal abscess extending into mediastinum — Axial (upper), coronal (lower left) and sagittal (lower right) CT with contrast of the neck shows a low density fluid collection in an enlarged retropharyngeal space that extends inferiorly deep into the mediastinum, best seen on the sagittal image.

The diagnosis was retropharyngeal abscess extending beneath T2 into the mediastinum resulting in a danger space abscess.

Teenager post heart transplant on cyclosporine with hypertension and seizures

MRI of posterior reversible encephalopathy syndrome / PRES — Axial FLAIR MRI without contrast of the brain shows bilaterally multiple areas of hyperintense signal in the cortex and subcortical white matter.

The diagnosis was posterior reversible encephalopathy syndrome.

Infant with seizures

MRI of pontocerebellar hypoplasia — Sagittal T1 MRI without contrast of the brain shows severe hypoplasia of the pons and cerebellum. The fourth ventricle is enlarged and the posterior fossa is of normal size.

The diagnosis was pontocerebellar hypoplasia.

Infant with bilateral bumps on the back of the head

CT of parietal foramina — Axial (above left) and coronal (above right) and 3D recon (below) of a CT without contrast of the brain show bilateral large holes in the skull, just medial to midline, in the posterior parietal region.

The diagnosis was parietal foramina.

Teenager with right vision loss

MRI of optic neuritis — Coronal FLAIR MRI without contrast of the orbits (above) shows bright signal in an enlarged right optic nerve. Axial (below lower left) and coronal (below lower right) T1 MRI with contrast of the orbits shows intense enhancement in an enlarged right optic nerve.

The diagnosis was right optic neuritis.

Preschooler with a gait disturbance

MRI of metachromatic leukodystrophy — Axial T2 (left) and FLAIR (right) MRI without contrast of the brain show bilateral symmetrical confluent increased signal throughout the white matter in a butterfly pattern.

The diagnosis was metachromatic leukodystrophy.

Preschooler with emesis

MRI of medulloblastoma — Sagittal T1 MRI without (left) and with (right) contrast of the brain shows a hypointense signal mass filling and distending the fourth ventricle that enhances homogeneously.

The diagnosis was medulloblastoma.

Teenager with pharyngitis and sepsis

US of Lemierre syndrome — Axial CT without contrast of the chest (above) shows multiple cavitary nodules within the lungs bilaterally. Sagittal spectral doppler US of the left internal jugular vein (below) shows thickening of the wall of the vein and no flow within.

The diagnosis was septic pulmonary emboli in a patient with Lemierre syndrome.

Teenager with headache and 3 weeks of photophobia

MRI of intracranial germinoma — Sagittal T2 MRI without contrast (left) shows a small isointense lesion in the region of the pineal gland that on sagittal (middle) and axial (right) T1 MRI with contrast of the brain shows mild enhancement.

The diagnosis was intracranial germinoma.

Teenager with sudden vision loss

MRV of idiopathic intracranial hypertension — Sagittal T1 MRI without contrast of the brain (left) shows a nearly empty sella. 3D reconstruction of an MRV with contrast of the brain looking from the top down (right) shows stenosis of the lateral aspect of the transverse sinuses bilaterally.

The diagnosis was idiopathic intracranial hypertension.

Teenager with developmental delay

MRI of semilobar holoprosencephaly — Axial (above), coronal (below left) and sagittal (below right) T1 MRI without contrast of the brain shows fusion of the frontal lobes, partial development of the posterior falx and occipital horns and separation of the occipital lobes, absent septum pellucidum, and hypoplasia of the corpus callosum.

The diagnosis was semilobar holoprosencephaly.

School ager hit in left eye by a baseball

CT of orbital blowout fracture — Coronal CT without contrast of the orbits (right) shows a discontinuity in the floor of the left orbit, with soft tissue herniated through the discontinuity into the left maxillary sinus.

The diagnosis was orbital blowout fracture.