Not So Benign: A Rare Atypical Ectopic Choroid Plexus Papilloma.

Choroid Plexus Papillomas (CPPs) are rare neoplasms (0.4-0.6 % of all brain tumors) arising from cuboidal epithelial cells of the choroid plexus. Atypical choroid plexus papillomas are even more rare and characterized by aggressive features of increased mitotic activity and frequent metastases even at diagnosis. Atypical choroid plexus papillomas accounted for 9% of choroid plexus tumors in the Surveillance Epidemiology and End Results (SEER) Database from 1978 to 2009. We describe a 56 year-old woman with a rare atypical choroid plexus papilloma ectopically located in the cerebellopontine angle and mistaken for a vestibular schwannoma or glossopharyngeal schwannoma. She demonstrated leptomeningeal seeding involving multiple cranial nerves and spinal cord. Besides papilledema she developed several neuro-ophthalmic features slowly over time from involvement of cranial nerves and subsequent intraparenchymal spread and radiation necrosis in the brainstem. Besides being rare, the cerebellopontine angle location of this tumor is also extremely uncommon making this a very unique case.

The Moving Carotid Artery: A Retrospective Review of the Retropharyngeal Carotid Artery and the Incidence of Positional Changes on Serial Studies.

BACKGROUND AND PURPOSE: Retropharyngeal carotid arteries are a clinically relevant anatomic variant. Prior studies have documented their incidence, but only a single case report has discussed the change in position of the carotid artery to and from a retropharyngeal location. The purpose of this study was to determine the prevalence of retropharyngeal carotid arteries and to evaluate the change in position of retropharyngeal carotid arteries over serial CT examinations of the neck. MATERIALS AND METHODS: A retrospective review of 306 CT examinations of the neck in 144 patients was performed. Patients with previous neck surgery or neck masses displacing the carotid arteries were excluded. The position of each carotid artery was evaluated on each examination. In patients with prior examinations, change or lack of change in position was recorded. The data were reviewed to assess changes in the position of the carotid arteries. RESULTS: Of the 144 patients evaluated, 34 were excluded. The final number of examinations included in the study was 249. Sixty-three of 110 patients had at least 1 comparison study. Twenty-three retropharyngeal carotid arteries were present on the baseline examination in 17 (15.5%) of 110 patients. There was documented change to or from a retropharyngeal position in 4 (6.3%) of 63 patients with comparison studies. CONCLUSIONS: The phenomenon of migration of the carotid arteries to and from a retropharyngeal position with time is confirmed by our study. It is important for physicians to be aware of this phenomenon to avoid potential procedural complications.