Jugular foramen lesion diagnostic dilemma – schwannoma or paraganglioma: A case report

Abstract

Introduction: Various anomalies occure in the jugular foramen. The most common lesion within the jugular foramen is the hypervascular glomus jugulare tumour followed by neurogenic tumors, predominantly schwannoma. Jugular foramen schwannoma can also be vascularized and frequently mimics paraganglioma.Case presentation: We present a case of a 36-year-old woman who presented with 8 to 10 months history of giddiness and vertigo, slowly progressive sensorineural hearing loss in left ear, gradually progressive left facial weakness (House Brackman grade III at the time of admission) and gait ataxia. A magnetic resonance imaging showed an avidly enhancing extra axial left cerebello-pontine angle space occupying lesion extending through the jugular foramen into the petrous temporal bone on the left side with prominent central flow voids. Paraganglioma was suspected and Digital Subtraction Angiography was done which showed tumour blush with arteriovenous fistula supplied by stylomastoid artery, which is branch of occipital artery. Surprisingly, histopathology after surgical resection revealed schwannoma.Conclusion: Prominent central vascularity and arteriovenous fistula with arterial supply from stylomastoid branch of occipital artery can be an unusual presentation for jugular foramen schwannomas. We describe architecture of vascualrity of jugular schwannoma and identify stylomastoid branch of occipital artery as its prime feeder.Keywords: jugular foramen schwannoma, paraganglioma