A novel tool for intralymphatic injection: the modified glass hypodermic needle

The use of contrast lymphangiography is a relatively new technique in lymphatic anatomical research, employed as a tool for evaluating lymphatic anatomy in fresh cadaveric specimens. With the use of microsurgical techniques to cannulate lymphatics, contrast media can enable the use of lymphangiography for evaluating lymphatic anatomy. However, the ability to cannulate lymphatics with diameters that are less than the smallest commercially available needles has been a significant limitation, and indeed a challenge. The smallest commercially available hypodermic needles have been 30-gauge needles, with 0.3 mm outer diameters. The lymphatics for cannulation in our studies are of the order of 0.1 mm, and other options have been required. We describe a novel technique for cannulating lymphatic vessels, creating a modified glass hypodermic needle. We have shown that these glass needles can be made with accuracy to diameters as low as 0.01 mm. Although 0.1 mm glass needles are the more commonly utilized in most dissections, we can now accurately create these glass needles to any caliber between 0.01 mm and 0.1 mm, based on the predicted lymphatic anatomy.