Migration of brachytherapy seeds causing symptomatic hydrocephalus

Brachytherapy for brain tumors requires the implantation of seeds into the brain parenchyma. We present the case of a 65-year-old female who underwent brachytherapy seed placement for metastatic adenocarcinoma. She later presented with headache, lethargy, and emesis found to be due acute hydrocephalus. A displaced seed migrated through the CSF and occluded the cerebral aqueduct resulting in obstructive hydrocephalus. Migration of brachytherapy seeds in extracranial use is well documented, but there are few reports of intracranial seed migration. Perhaps use of brachytherapy seeds in an area close to the ventricles may require further study or technical refinement.