Role of Digital Subtraction Angiography in the Preoperative Assessment of a Patient with a Petrosquamous Sinus: a Case Report.

We report a case of a 15-year-old Indian girl who presented with tinnitus, pain and ear discharge for one month and was preliminarily diagnosed with Chronic Suppurative Otitis Media (CSOM) with mastoiditis. She underwent a routine presurgical CT scan which revealed an aberrant vein, making it essential to exercise caution during surgery for CSOM. The aberrant vessel was identified as a Petrosquamous Sinus. A Petrosquamous Sinus is a persistent fetal vein that connects the transverse sinus with the retromandibular vein and may regress in an individual by birth. Its importance lies in the risk of haemorrhage it carries during otological surgeries. A Digital Subtraction Angiography proved to be a vital step in isolating the path of the vein for better visualisation of the course, thus giving a better idea about the anatomical relations of the vessel during the surgery. The tympanoplasty was performed with care to prevent damaging the vein. The patient had no complications in the postoperative period and made a quick recovery.