ANATOMIC REPORT ANATOMIC LANDMARKS FOR THE CERVICAL PORTION OF THE THORACIC DUCT Kevin Ammar, M.D. Pediatric Neurosurgery, Children’s Hospital, Birmingham, Alabama R. Shane Tubbs, M.S., P.A.-C., Ph.D. Pediatric Neurosurgery, Children’s Hospital, and Department of Cell Biology, University of Alabama at Birmingham, Birmingham, Alabama Matthew D. Smyth, M.D. Pediatric Neurosurgery, Children’s Hospital, Birmingham, Alabama John C. Wellons III, M.D. Pediatric Neurosurgery, Children’s Hospital, Birmingham, Alabama Jeffrey P. Blount, M.D. Pediatric Neurosurgery, Children’s Hospital, Birmingham, Alabama George Salter, Ph.D. Department of Cell Biology, University of Alabama at Birmingham, Birmingham, Alabama W. Jerry Oakes, M.D. Pediatric Neurosurgery, Children’s Hospital, Birmingham, Alabama Reprint requests: R. Shane Tubbs, M.S., P.A.-C., Ph.D., Pediatric Neurosurgery, Children’s Hospital, 1600 7th Avenue South, ACC 400, Birmingham, AL 35233. Email: richard.tubbs@ccc.uab.edu Received, February 24, 2003. Accepted, May 7, 2003. OBJECTIVE: Avoidance of injury to the thoracic duct during neurosurgical procedures involving the cervical region depends on a working knowledge of its location. This study evaluates superficial anatomic landmarks for the cervical portion of the thoracic duct that may be encountered in neurosurgery of the neck. METHODS: Fifteen dissections of human cadavers were performed to study the relationship between the proximal thoracic duct and superficial landmarks (e.g., the cricoid cartilage and sternal notch of the manubrium). RESULTS: The cervical portion of the thoracic duct was found to be approximated by a roughly 4.4-cm 2 region in the left supraclavicular area beginning approximately 2.0 cm lateral to the midline and 3.5 cm superior to the sternal notch, extending superiorly to a point roughly 3.5 cm from the midline and 2.5 cm inferior to the cricoid cartilage, and terminating within the venous system at a point approximately 4.5 cm lateral to the midline and 3.0 cm superior to the sternal notch. CONCLUSION: Through an increased appreciation for its location, injury to the thoracic duct may be minimized. KEY WORDS: Anatomy, Complications, Lymphatics, Neck, Surgery Neurosurgery 53:1385-1388, 2003 DOI: 10.1227/01.NEU.0000093826.31666.A5 www.neurosurgery-online.com A n appreciation of the location of the proximal portion of the thoracic duct is valuable during neurosurgical proce- dures involving the cervical region, such as anterior cervical spinal fusion, brachial plexus repair, tunneling for ventriculoperitoneal/ pleural shunting, carotid endarterectomy, ventriculolymphatic shunting, and vagal nerve stimulator or central venous line place- ment. Although the anatomic course of the duct has been well documented, external an- atomic landmarks for this structure are lack- ing. This study evaluates superficial anatomic landmarks for the localization of the cervical portion of the thoracic duct. MATERIALS AND METHODS Fifteen adult, formalin-fixed cadavers were used for this study. Nine were men, and six were women. The age range was 57 to 81 years (mean, 75 yr). Careful dissection of the left anterior cervical region of each specimen was performed; the thoracic duct was observed from its entry into the root of the neck, where it exits the thoracic inlet dorsal to the left subclavian artery, along the lateral curvature of the duct anterior to the scalenus anterior muscle and phrenic nerve, and ultimately to its point of termination at or near the junction of the left subclavian and the internal jugular veins (Fig. 1). Three points along this course were recorded: 1) the point of entry into the root of the neck, 2) the superiormost aspect of the arch of the duct, and 3) the point of termination into the venous system. Horizontal and vertical co- ordinates for each of these points were then obtained from the midline of both the cri- coid cartilage and the sternal notch of the manubrium (Fig. 2). Variability of clavicular morphology precluded its use as a reliable landmark. RESULTS Table 1 lists the distance in centimeters from the midline (x), the vertical distance from the cricoid cartilage (y c ), and the vertical distance from the sternal notch (y s ) for each of the three NEUROSURGERY VOLUME 53 | NUMBER 6 | DECEMBER 2003 | 1385