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Biomedical subjects

J Ammon

Publications and source records attributed to J Ammon.

At least 55 records · Page 3Linked to original sources
PubMed1980

[Physico-technical irradiation planning for the therapy of oesophagus carcinomas by means of computed whole-body tomography (author's transl)].

It is particularly difficult to establish a physico-technical irradiation plan for the thoracic part of an oesophagus carcinoma. This is due to the considerable modifications of the thoracic cross-section within the longitudinal axis of the radiation field. Therefore, tomographic cross-sections were made of the upper, the middle and the lower plane of the radiation field. The percentage dose distributions could be determined with a process computer (system TPS, Phillips) for different irradiation techniques and irradiation equipments. Examinations of 21 patients showed that the best dose distribution, i.e. a distribution which spares the lung and spinal marrow regions adjacent to the target volume, is obtained by an excentric moving field therapy. Furthermore, localisation and dimensions of inhomogeneities are indicated by computed tomography which makes possible to take into consideration these inhomogeneities when calculating the dose. It was found that the irradiation times can so be reduced by more than 20%. We are therefore of the opinion that it is necessary to establish individual cross-sections of the body by computed tomography when elaborating a physico-technical irradiation plan for the treatment of an oesophagus carcinoma.

Esophageal Neoplasms↗
PubMed1979

[Lymphangitis carcinomatosa of the lung in carcinoma of the prostate: frequency, radiological appearances and clinical significance (author's transl)].

Lung metastases from carcinoma of the prostate usually manifest themselves as radiologically diffuse lymphangitis carcinomatosa. Unlike the pathological findings, a radiological diagnosis is relatively uncommon. We have investigated this retrospectively in 230 patients; in 192, radiographs were available for study. In over 10% lung metastases were found, mostly in the form of lymphangitis carcinomatosa. In view of the bad prognostic significance and therapeutic implications of lymphangitis carcinomatosa, it is important to bear this in mind and to look for it radiologically.

Aged↗
PubMed1979

[Total body computer tomography or the urogenital system (author's transl)].

Computer tomography cannot only produce transversal sections of the body, but also evaluate the x-ray absorption values of various organs and tissues. It was first used in the investigation of the brain and has influenced the use of traditional neuroradiological techniques. Computer tomography can be used in special cases of diseases of the urogenital system. It is especially helpful in the diagnosis of primary or secondary retroperitoneal processes and also for tumors of the kidney. It allows effective frequent follow up of various therapies and has no side effects. Also in the follow up of various tumors, this noninvasive technique can demonstrate possible recurrences. It appears however that the total body computer tomography will not replace traditional radiological technique. During treatment and follow up of malignant tumors of the urogenital system however it appears very helpful.

Adenocarcinoma↗
PubMed1978

[Computer tomography for TNM based radiation planning of urological tumours (author's transl].

From the extensive statistics concerning treatment results of urological tumours which are available from central tumour registers, a first draft of a treatment plan has been worked out, which is based on tumour spread. Since the extent of tumour invasion is documented by the TNM system of the UICC, one is justified in speaking of TNM orientated treatment planning. For planning it is necessary to consider not only tumour type and depth of infiltration of local tissues, but also the lymph node anatomy, whether the nodes are involved or not. Computer tomography assist significantly in the performance of such TNM orientated treatment planning, particularly in determining the extent of the volume to be irradiated, It must be stressed that computer tomography does not replace the use of simulators, but that it is a valuable addition. In our view, computer tomography has also an undoubted value in treatment planning of urological tumours where palliation only is the aim. It provides the possibility of checking the effect of the chosen treatment by a non-invasive diagnostic method.

Adenocarcinoma↗
PubMed1978

[Technical realization of a systematized radiation therapy, founded on the TNM system, of tumors in the regions of the head and neck (author's transl)].

Modern radiation therapy of tumors within the regions of the head and neck regards not only the concept of the target volume but also the probability of affection to the lymphatic chains. Frequency of spread to lymph nodes depends on the size of the primary tumor, and thus the extent of radiotherapeutic practical measures can be conformed to the TNM system. A radiation therapy planned in view of the TNM classification may be termed, therefore, as a systematized radiation therapy. From the standpoint of these considerations irradiation techniques using a telecobalt therapy unit and a betatron have been examined considering the application to individual toumor sites and tumor volumes in the regions of the head and neck. The techniques being most appropriate for tumors of the head and neck, with regard to the various sites or volumes, and taking into account the target volume as well as the lymphatic chains concerned are here presented.

Cobalt Radioisotopes↗
PubMed1977

[TNM-system orientated radiological therapy in prostatic carcinoma (author's transl)].

The classification of prostatic cancer according to the TNM-system in contrast to the older staging systems results in a change in radiological therapy planing. The radiological techniques for the classification of N (lymphnodes) and M (metastases) are explained. Together with T (local tumore growth) these categories define the outline for the radiological therapy. The different radiation techniques are explained.

Bone Neoplasms↗
PubMed1976

[Five-years synchronized radiotherapy in treatment of carcinoma of the head and neck: clinical results, 1970--1974 (author's transl)].

Increased tumor radiosensitivity can be achieved by the technique of synchronisation, although as yet this relationship has only been partial. Our clinical experiences from 1970-1974 with this technique lead to the following considerations: 1. Synchronized radiotherapy (Telecobalt) is administered twice weekly, independent of adjunctive medications (such as fluoro-uracil, vincristin or bleomycin). 2. Synchronized radiotherapy does not change previous indications for operative intervention. 3. The described technique permits successful treatment of advanced tumors as well as postoperative tumor recurrences of recurrences in previously-irradiated tisssues. 4. The radiosensitivity of poorly oxygenated tumor tissues may be increased. 5. Radiation dosage must not be reduced. 6. Distant tumor metastases can also be treated with additional chemotherapy (as synchronized chemotherapy).

Antineoplastic Agents↗
PubMed1975

[Clinical application of iodine 123 with special consideration of radionuclide purity, measuring accuracy and radiation dose(author's dose)].

Iodine 123 is a nearly "ideal" radionuclide for thyroid imaging. The production of Iodine 123 requires cyclotrons or accelerators. The production of multicurie amounts of Iodine 123 has been suggested through the use of high-energy accelerators (less than 60 MeV). Most of the methods for the production of Iodine 123 using a compact cyclotron result in contamination with f.e. Iodine 124 which reduces the spatial resolution af imagining procedures and increases the radiation dose to the patient. The radiation dose has been calculated for three methods of production. The various contamination with Iodine 124, Iodine 125, and Iodine 126 result in comparable radiation dose of Iodine 131, provided that the time between production and application is more than four half-live-times of Iodine 123.

Child↗