# Fenestration and Bifurcation of the Internal Jugular Vein; Surprises During Head and Neck Surgery

## TL;DR

This paper reports three rare anatomical variations of the internal jugular vein encountered during head and neck surgeries, emphasizing the importance of pre-operative imaging to avoid surgical complications.

## Contribution

The paper contributes three clinical case reports of IJV bifurcation and fenestration, highlighting their surgical implications.

## Key findings

- Three cases of IJV anomalies (bifurcation and fenestration) were identified during head and neck surgeries.
- Pre-operative imaging and anatomical knowledge are critical to prevent intra-operative complications.
- The spinal accessory nerve and omohyoid muscle were found in variable positions relative to the IJV anomalies.

## Abstract

The internal jugular vein (IJV) is one of the major vessels in the neck and serves as an important landmark for surgeons during head and neck surgery. Anomalies of the IJV are rare and seldom encountered by the surgeons. However, a comprehensive knowledge of these variations is essential for better surgical dissection and to prevent intra-operative mishaps. The variations can be in the forms of bifurcation, trifurcation, duplication, fenestration and posterior tributaries of the IJV. Here we describe three cases of bifurcation and fenestration of the IJV that we encountered in our surgical practice.

In the first patient, we found an empty fenestration of the right internal jugular vein during a selective neck dissection for tongue carcinoma. The spinal accessory nerve was passing lateral to the IJV above the level of the fenestration. The second patient was operated for a left vagal schwannoma in the neck. During the surgery, we found a bifurcation of the left IJV, and the two tributaries fused just above the left omohyoid muscle. The third patient, a sixty-year-old lady also had a bifurcation of the left IJV. It was found during a modified radical neck dissection for carcinoma ex pleomorphic adenoma of the left parotid gland.

An in-depth knowledge of the anomalies of the internal jugular vein and meticulous evaluation of the pre-operative imaging may help the surgeons in preventing any intra-operative catastrophe during head and neck surgery.