Surgical approach to internal and external jugular venous agenesis: case report

During reconstructive planning for mandibular resection and reconstruction, it was noted that the left internal and external jugular veins were absent, with a considerable compensatory internal jugular vein present on the contralateral side. An accidental finding in the CT angiogram of the head and neck was assessed. Osteocutaneous fibular free flap is a well-established reconstructive surgery for mandibular defects that can involve anastomosis of the internal jugular vein and its tributaries. A 60-years-old man with intraoral squamous cell carcinoma, initially treated with chemoradiation, developed osteoradionecrosis of his left mandible. The patient then underwent resection of this portion of the mandible with reconstruction by osteocutaneous fibular free flap with virtual surgical planning. During reconstructive planning for the resection and reconstruction, it was noted that the left internal and external jugular veins were absent, and a noteworthy compensatory internal jugular vein was present on the contralateral side. We report a rare case of this combination of anatomical variations within the jugular venous system. Unilateral agenesis of the internal jugular vein has been reported, but a combined variation with ipsilateral agenesis of the external jugular vein and compensatory enlargement of the contralateral internal jugular vein has, to our knowledge, not been reported on previously. The anatomical variation reported in our study will be useful during dissection, central venous catheter placement, styloidectomy, angioplasty/stenting, surgical excision, and reconstructive surgery.