A case of left-sided absence and right-sided fenestration of the external jugular vein and a review of the literature.

The external jugular vein is increasingly being used as the recipient vein in head and neck tissue transfers, and for cannulation to conduct diagnostic procedures or intravenous therapies. The variations in the patterns of its course, and knowledge of these variations, are therefore important. We report on a bilateral external jugular vein anomaly found during the neck dissection of an approximately 75-year-old female cadaver, a case which has hitherto not been reported. The vein was absent on the left and fenestrated on the right. An embryological evaluation and the clinical implications of the anomaly are described. Clinicians and surgeons performing vascular or reconstructive surgery should be made aware of this variation of the external jugular vein to prevent inadvertent injury.