Surgeries can sometimes reveal unusual things about a patient. A recent paper in BMJ Case Reports has described a particularly rare discovery: a person with two internal jugular veins. Duplication of this vein is rare, with only four other cases written about in scientific literature to date.
The internal jugular vein is located in the carotid sheath in the neck, alongside the vagus nerve and carotid arteries. It runs down the left and right sides of the neck, delivering blood from the neck, face, and brain to the right atrium of the heart. The vein is not protected by cartilage or bone, and damage to the internal jugular vein can cause rapid and significant blood loss that can be fatal.
A 40-year-old man came to a surgical department in India with a lesion in his mouth, which was diagnosed as a type of skin cancer called squamous cell carcinoma. Plans were made to surgically remove the cancer, and a neck dissection was started. During the dissection, the surgeons spotted an enlarged lymph node. When moving the right internal jugular vein out of the way to access the lymph node, they found a surprise – a second internal jugular vein was nestled behind the first. The two twin veins eventually came together as one, below the omohyoid muscle in the front of the neck.
The development of the vascular system is complex and can lead to variations in the internal jugular vein, with well-documented variations involving differences in size or shape. These variations can make surgery on the area more complicated. It has been reported that around two-thirds of variations occur on the left-hand side. However, this rare duplication was of the right side – unfortunately for the surgeons, as the right is slightly larger than the left, meaning the risk of blood loss from damage during surgery is increased.
The higher risk of blood loss, combined with multiple branches draining into both veins, meant that the surgeons needed to adopt an even more cautious approach than usual. Luckily, aside from the unusual discovery, the surgery went as planned. A CT scan of the patient was examined, confirming that the duplication was in the base of the neck at the level of the C6 vertebra.
This discovery, while rare and exciting, was taken extremely seriously by the surgeons due to the increased risk to the patient. “The surgical implications cannot be over emphasised,” they write in the paper, recommending that in the future, surgeons carry out a “careful preoperative study of CT to rule out any variations in the vasculature of head and neck.”