Computed Tomography and Radiographic Indirect Lymphography for Visualization of Mammary Lymphatic Vessels and the Sentinel Lymph Node in Normal Cats

Abstract

The potential of computed tomography indirect lymphography (CT-indirect lymphography) and radiographic indirect lymphography to demonstrate the draining lymphatic vessels and sentinel lymph node of normal mammary glands was tested in 31 healthy female cats. The lymphatic drainage of each mammary gland was studied initially by CT-indirect lymphography after intramammary injection of 0.5 ml of iopamidol, followed by images acquired at 1, 5, 15, and 30 min after injection. One day after CT-indirect lymphography, the lymph drainage of the mammary gland was assessed using radiographic in direct lymphography af terintramammary injection of 0.5 ml of ethiodized oil followed by radiographs made at 1, 5, 15, 30, 45, and 60 min after injection. The time between intramammary injection and opacification of the draining mammary lymphatic vessels and the sentinel lymph node, the duration of adequate opacification of the draining mammary lymphatic vessels and of the sentinel lymph node and also the number and course of draining mammary lymphatic vessels and location of sentinel lymph node were compared for CT-indirect lymphography vs. radiographic indirect lymphography in each examined gland. This results suggest that radiographic indirect lymphography is easy to perform and can be used for accurate demonstration of the draining lymphatic pathways of mammary glands in radiographs made at 5-30 min after injection. However, CT-indirect lymphography was able to better demonstrate small lymphatic vessels and accurately define the exact topography of the sentinel lymph node in images acquired at 1 min after injection.

Indirect Computed Tomographic Lymphography for Iliosacral Lymphatic Mapping in a Cohort of Dogs With Anal Sac Gland Adenocarcinoma: Technique Description

“…Although indirect CT lymphography has been previously described for peripheral mammary lymphatic mapping in cats, this study investigated a technique for lymphatic mapping of a complex internal lymphocenter in clinically affected dogs. In this small cohort of dogs, it appeared that patient positioning at the time of indirect CT lymphography may strongly impact the timing of sentinel lymph node identification in the iliosacral lymphatic center.…”

“…However, gold‐standard methods of sentinel lymph node mapping used in people, such as lymphoscintigraphy, are not widely available to veterinarians. Indirect computed tomographic lymphography has been used successfully in both people and experimental animals for lymphatic and sentinel lymph node mapping . As CT capability has become more readily available to veterinarians, the objective of this study was to evaluate the feasibility of an indirect CT lymphography technique as a possible method for sentinel lymph node identification in a complex lymphocenter using a natural model of disease prone to lymphatic metastasis.…”

Tumors of the Mammary Gland

“…176 In a report of male cats diagnosed with mammary carcinomas, a trend toward more frequent local recurrence correlated with more conservative resections. 126,189 Published techniques in the cat include CT evaluation following intramammary injection of iopamidol and radiographic imaging following intramammary ethiodized oil injections. For some cats with excessively loose mammary tissue, a bilateral chain mastectomy can be performed during a single surgical session if minimal postsurgical tension can be achieved, but subjectively these cats may have a more difficult recovery (Figure 27-6).…”

“…159 Thus, for cats, a unilateral or staged bilateral chain mastectomy is recommended for treatment of mammary carcinoma. 189 underpowered or not stratified according to treatment. For tumors that are fixed, muscular fascia or portions of the body wall should be included with en bloc resections.…”

Lymphatic Drainage of the Cranial Thoracic Mammary Gland in the Domestic Cat

“…The first lymphographic studies of the mammary lymphatic drainage in the cat were made in 2009 using Lipiodol UltraFluid as contrast agent (Papadopoulou et al, 2009;Patsikas et al, 2010).…”