Gamma Ray Detection Probe

The idea of using a hand-held probe for the localization of diseased tissue was first reported by William G. Myers in 1960 12 . The first reported use of the probe for RIGS was in 1984 13 . The design of the probe is based on the use of a semiconductor detector in a hand-held instrument. The probe uses a built-in 12-mm cadmium telluride detector, together with a preamplifier, and has the ability to detect gamma rays from a radioactive tracer. The gamma photons detected by the crystal are con-...

Radiation Exposure Of Staff

Various hospital staff members are exposed to radiation during the sentinel node procedure. Because the surgeon is in closest contact with both tumor and sentinel node, dose calculations will be focused primarily on this person. Radiation exposure of others e.g., nurses and pathology personnel can be deduced from the values that apply to the surgeon. The skin of the surgeon's hands is expected to receive the highest dose and therefore serves as the dose-limiting organ. The radiation exposure of...

Metastatic Melanoma In Regional Lymph Nodes

Sentinel Lymph Node

Once patients develop metastatic melanoma in their regional nodes, prognostic factors based on the primary melanoma contribute very little to the prognostic model. For most solid tumors, including melanoma, the most powerful predictor of survival is the presence or absence of lymph node metastases. The presence of lymph node metastases decreases the 5-year survival of patients approximately 40 compared with those who have no evidence of nodal metastases. Much time, effort, and expense is placed...

Blue Dye Mapping The Concept

Sentinel Lymph Node Mapping

The use of colored substances to demonstrate lymphatic vessels and lymph nodes is not a new concept. It was the technique employed by a number of the earliest anatomists who sought to map human cutaneous lymphatic drainage pathways see Chapter 2 . By injecting materials such as Prussian Blue dye and Chinese ink, they confirmed that lymphatics and blood vessels were distinctly separate entities and produced the first recorded maps of cutaneous lymphatic drainage pathways. In more recent times,...

Results

99mtc Nanocolloid

The images are usually easy to interpret. The above-described technique depicts the lymphatic duct s in 80-98 of patients. In our hands, it hardly ever fails to visualize the sentinel node s 42,44-48 . Lymphatic drainage is complex in the neck and this is the most difficult lymphatic field for the interpretation of lymphoscintigraphy. We could not identify a sentinel node in 3 of 25 12 patients with a melanoma in the head and neck region 49 . O'Brien and coworkers faced this problem in 2 out of...

Intraoperative Use Of A Gamma Probe

Intraoperative Gamma Probe

Although definite blue staining of a sentinel node with identification of at least one blue-stained afferent lymphatic channel entering the node currently remains the gold standard for assessment of whether a lymph node is or is not a true sentinel node, intraoperative use of a gamma detection probe can provide valuable confirmatory evidence. A number of compact, lightweight gamma probes are now available which can be used intraoperatively to assist with the sentinel lymphadenectomy procedure....

Microanatomy Of The Lymphatic System

Lymphatic System Collecting Vessels

Although there are remarkable similarities in the lymphatic microanatomy within different organs, there are also some essential differences 2 . This review will deal with the common ultrastructural features first and then examine the differences between organs. The lymphatic system Fig. 1 begins as a network of blind ending capillaries which absorb lymph from the interstitial spaces. These capillaries are called initial lymphatics and are also known in the literature as prelymphatics, lymphatic...

Lymphatic Mapping Of The Skin

Sappey Lymphatic

The first comprehensive descriptions of the lymphatic drainage of the skin were based on the elegant work of the anatomist Sappey, who in the nineteenth century injected mercury into the lymphatics of cadavers to display the lymph channels 3,4 . He reported drainage to the axilla and groin from the skin of the trunk Figs. 1-3 and showed a vertical midline zone anteriorly and posteriorly where drainage tended to overlap. A similar zone was identified passing horizontally around the waist from...