SPECT/CT Lymphoscintigraphy to Locate the Sentinel Lymph Node in Patients with Melanoma

Excerpt

The major strength of nuclear medicine imaging has always been its high functional resolution, and a good example of this is lymphoscintigraphy using radiocolloids to map the location of the lymph node receiving direct lymph drainage from a solid tumor site. Using this technique the one or two sentinel nodes of the 1,000 or more nodes in the patient are radiolabelled and clearly visible on lymphoscintigraphy.1 This same technique, however, also nicely illustrates a limitation of nuclear medicine images: their low anatomical resolution. The surface location of these sentinel nodes (SN) can be marked and we can measure the depth of the SN from the skin, but the planar nuclear medicine images provide no anatomical information. …