Agenesis of internal jugular vein a cause for concern.

Internal jugular vein is one of the major contributors to the venous drainage from the intracranial structures. Neck dissections which necessitates ligation of internal jugular vein leads to significant alteration of cerebrospinal fluid pressures in the range of three times for unilateral ligation to five times in cases of bilateral ligation. Agenesis of internal jugular vein merits concern prior to central venous cannulation and ligation during radical neck dissection for metastatic nodes in head and neck cancers.