Lymph node distribution in the central compartment of the neck: an anatomic study.

Background: Dissection of the central compartment of the neck (CCN) is performed for proven or suspected lymph node metastases of thyroid carcinoma. During this procedure, the recurrent laryngeal nerves and the parathyroid glands are at risk. The purpose of this study was to determine the anatomic distribution of the lymph nodes in the CCN.

Methods: The anatomic distribution of the lymph nodes in the CCN was studied by dissection of 30 fresh cadavers. The soft tissue between the cricoid cartilage and the innominate vein, carotid arteries, and prevertebral fascia was removed and divided according to CCN sublevels. Nodules were identified by palpation in the specimen and sent for pathological examination.

Results: Three to 44 (18.5 ± 10.29) nodules were identified macroscopically. Two to 42 nodules were confirmed as lymph nodes after microscopic examination. The lymph node distribution was as follows: precricoid: 0 to 2 (0.9 ± 0.72); pretracheal: 1 of 35 (12.4 ± 8.19); lateral to the right recurrent laryngeal nerve (RLN): 0 to 11 (3.4 ± 2.34); and lateral to the left: 0 to 4 (1.7 ± 1.30). Twenty-six parathyroid glands were removed by 14 dissections. The innominate vein was found at 15 mm above the superior border of the clavicles to 35 mm below on the left side of the neck and 5 to 45 mm on the right side.

Conclusion: The number of confirmed lymph nodes in the central neck varied from 2 to 42. Sixty-seven percent of the lymph nodes were in the pretracheal sublevel. There was no division between level VI and VII lymph nodes. Additionally, the innominate vein was found to be from 15 mm above the superior border of the clavicles to 35 mm below on the left side of the neck and 5 to 45 mm on the right side. Parathyroid glands were identified to be far away from the thyroid gland.