Lymphography

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When lymphography or lymphography is a 1952 introduced by JB Kinmonth method of diagnosis for imaging rays of lymphatics and lymph nodes . Different variants are used, but they are all based on the same principle:

Test substances are used that are transported away with the lymph flow and

In X-ray lymphography, a distinction is made between direct and indirect lymphography and lymph scintigraphy.

Direct lymphography

This procedure is quite complex. It can be used for the lymphatic drainage pathways of the arms and legs and the further lymphatic drainage in the trunk of the body including the lymph node stations. With regard to the representation of the anatomical relationships, it is the most precise and thus also allows the assessment of relatively fine structures. After dye marking the local lymphatic vessels and surgical exposure under local anesthesia, a direct injection of contrast medium (16-20 ml) into the lymphatic system is carried out for up to two hours with a special pump. X-rays during the injection and up to 32 hours afterwards at certain intervals document both the lymphatic tracts and the lymph nodes in the entire outflow area of ​​the lymph vessels visited anatomically and allow conclusions to be drawn about certain diseases, such as malignant diseases of the lymph system (leukemia, lymphomas, carcinoma metastases ) as well as lymph drainage disorders.

Indirect lymphography

This procedure is less time consuming but also less accurate. Here, an X-ray contrast medium is injected into or under the skin and transported with the tissue lymph into the local lymphatics and lymph nodes, which then become visible in the X-ray image. Since only very small amounts of particularly tissue-friendly contrast medium can be used and the removal does not always work, this procedure can only be used to examine the local lymphatic channels and lymph nodes. It is mainly used for the clarification of lymphatic transport disorders or inflammatory diseases.

Overall, the lymphography methods have lost a lot of importance in the last decades as a result of the improvements in the accuracy of computed tomography and magnetic resonance tomography on the one hand and the therapeutic methods on the other hand and are only used in rare cases.

Lymph scintigraphy

Like all nuclear medicine procedures, lymph scintigraphy also has a relatively poor level of detail, since the spatial resolution - even with modern detectors - for the weak radioactive impulses of the indirectly injected test substances is inherently limited. Essentially, only the function of the lymphatic evacuation can be checked and a quantitative detection of lymph nodes can be carried out. A detailed qualitative assessment of the shape is not possible.

Current importance for lymph scintigraphy has emerged in recent years in the therapy of breast cancer , prostate cancer and penile cancer . On the one hand, it is of crucial importance for the prognosis and treatment of these types of cancer to have reliable information about the spread of the tumor in the local lymphatic drainage. On the other hand, surgical exploration is time-consuming and also associated with certain risks for the patient (lymph drainage disorders). Studies have shown that it is sufficient to examine the first lymph node that is reached by the lymphatic drainage of the tumor . If the sentinel lymph node (ger .: sentinel lymph node ) affected, so must the fullest possible removal ( lymphadenectomy ) take place all local lymph nodes. If there is no infestation here, it can be assumed with sufficient certainty that there has been no spread into the lymphatic system.

Lymph scintigraphy is currently used here. Before the operation, small depots of a weakly radioactive test substance are injected into the tissue around the tumor, and then its removal is monitored by the lymphatic flow. If one or more lymph nodes appear, they are located more precisely and marked with a small colored marker on the patient's skin for the surgeon.

During the operation, the surgeon can use a special measuring probe to locate the lymph nodes based on the stored radioactivity, remove them and send them for tissue examination.

Radiation exposure

Radiation exposure through x-rays or radioactive decay (lymph scintigraphy) is inherent in all lymphography methods. The exposure depends on the number of X-rays taken or the amount of activity administered (with about 20–30 MBq Tc-99m, about one-thirtieth compared to a brain, heart or skeletal scintigraphy).

Among the competing methods, only magnetic resonance tomography manages without ionizing radiation.

Individual evidence

  1. ↑ Horst Kremling : On the development of clinical diagnostics. In: Würzburger medical history reports 23, 2004, pp. 233–261; here: p. 241.
  2. ↑ W. Sturm: Laparoscopic pelvic sentinel lymphadenectomy in prostate cancer. Dissertation, Eberhard-Karls-Universität zu Tübingen, 2007
  3. ↑ P. Heidenreich et al.: The concept of the sentinel lymph node: status and clinical significance. In: Deutsches Ärzteblatt 98, 2001, pp. A-534 / B-434 / C-408
  4. ↑ Cervical cancer: what surgical procedures are there? , Cancer Information Service of the German Cancer Research Center (DKFZ), Heidelberg. June 16, 2006. Last accessed September 4, 2014.