PNR Head 16

History

22 month old M ex-premie status post VP shunt for congenital hydrocephalus, presents with one week of fever and vomiting

Major Findings

Our case (CL1173) compared to prior CT from 9 months earlier (CL1025):

Interval enlargement and entrapment of the 4th ventricle with resultant mass effect on the brainstem (cerebellar atrophy is unchanged)
Right frontal catheter exchanged for right parietal shunt with decompression of the right lateral ventricle while the left ventricle is unchanged
Maxillary sinus disease

Teaching Points

"Isolation" or "entrapment" of the 4th ventricle is a complication in shunted patients. Associated brainstem compression can cause ataxia, nystagmus, dysarthria, pyramidal weakness, cranial nerve palsies, eye movement disorders, etc.

See this article for more information:

Sometimes you will be asked to compare to prior exams - please always use the most recent, which may be an US or an MRI.

This can be very challenging. Use cross-referencing in PACS to make sure you measure similar portions of the ventricle.

And don't just eyeball; measure, measure, measure!

Accession: CL1173

Study description: CT HEAD W/O CONTRAST