A Rare Combined Variation of the Fenestrated External Jugular Vein, Absent Retromandibular Vein, and Hypoplastic Internal Jugular Vein

A unique venous pattern was observed on the left side of the neck in a 70-year-old male cadaver. Variations were observed in the formation of the external jugular vein (EJV) associated with a hypoplastic internal jugular vein (IJV). The retromandibular vein did not form, and the superficial temporal vein continued as the EJV. The linguofacial and maxillary veins united and drained into the EJV, whereas the posterior auricular vein was absent. In addition, a slit-like fenestration in the EJV was present in the middle of the vein, which was 41.54 mm long. IJV of the same side was hypoplastic throughout its course in the neck, and the external diameter was 6 mm. IJV and EJV are frequently accessed for central venous pressure monitoring or intravenous infusion and are encountered during cervical lymphadenectomy. Awareness of the anatomical irregularities is critical to avert unanticipated complications.