Chylous Fistula of the Neck Workup

Updated: Sep 15, 2022
  • Author: Philip E Zapanta, MD, FACS; Chief Editor: Arlen D Meyers, MD, MBA  more...
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Laboratory Studies

Chyle has unique chemical characteristics that enable easy and accurate diagnosis. It has a high concentration of chylomicrons with high triglyceride (>5 g/L) and low cholesterol concentrations. Furthermore, chyle stains with lipophilic dyes, such as Sudan III, and when mixed with 1-2 mL of ethyl ether, chyle turns from milky to clear fluid.


Imaging Studies


Chest radiographs in patients with chylous fistula can demonstrate a soft-density opacity at the root of the neck. Chylothorax is an uncommon complication of chylous fistula and may be seen on chest radiographs as a pleural effusion.

CT scanning

CT scanning is used to confirm the presence, site, and extent of a neck collection. However, it is not useful for accurate localization of the thoracic duct injury.


Lymphangiography is an invasive procedure used to visualize the lymphatic vessels and thoracic duct, as well as to identify the site of a chyle leakage. It requires catheterization of afferent lymph vessels in the foot and is associated with adverse effects such as local tissue necrosis, fat embolism, lymphoedema, and hypersensitivity reaction.


The use of nuclear medicine to identify the site of chyle leakage following thoracic duct injury has become increasingly popular. Lymphoscintigraphy is a quick, noninvasive technique that involves the administration of oral and intravenous water-based radionuclide, the flow of which is traced with a gamma camera or proton-emission scanner. Computer analysis of the data creates images of the lymph flow and determines the speed of uptake, allowing localization of the site of chyle leakage. [14, 15]


Direct Visualization

Leaks are typically low volume thus making identification difficult. If an intraoperative leak is suspected, the anesthesiologist may apply positive pressure, similar to the Valsalva maneuver, thus increasing intra-abdominal pressure and the flow of the leak. Alternately, manual abdominal compression may be applied. [16]