Abstract
HomeRadiologyVol. 17, No. 3 PreviousNext ArticlesVienna ClinicsCoutard's Method of Roentgenotherapy as Seen during a Visit in Paris1Author AffiliationsMilwaukee, WisconsinPublished Online:Sep 1 1931https://doi.org/10.1148/17.3.563MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In AbstractCoutard reported, in 1928, during the International Congress of Radiology, in Stockholm, on his method of irradiation and his results in carcinomas of the upper air passages. His results were far superior to anything which others had been able to achieve in this type of carcinoma by roentgenotherapy alone; they were as good as the results at the Radiumhemmet Stockholm by means of electrocoagulation and radium therapy. Coutard's method is used to-day in many places. The reason for reporting my impressions during a visit to Coutard's institute are two: (1) the many similarities to the school of Vienna; (2) the fact that this method is often imitated only so far as the name is concerned, but not with identical technic.The French radiologists, under the guidance of Regaud, have employed medium and small doses in their therapy. The reason for this is that a much larger total dose thus can be given than with the single high dose technic, as used commonly by German roent-genotherapists. What is new in the method of Coutard is that it decreases markedly the hour-intensity, that is, the number of r given per hour, while the total dose is markedly increased. The single doses are very small and distributed over a long time. In this way Coutard's method corresponds in principle with the method which G. Schwarz some time ago. The two methods differ in the manner of decreasing the hour-intensity. Coutard decreases it to about the twenty-sixth part of the average, figuring that in the average 650 r are given in 30 min. to reach a skin erythema dose. The dose which is given to each skin field during six weeks is 2,100 r; the dose effective on the tumor is 8,400 r. The decrease in the hour-intensity with 180 K.V. max. and 3 ma. is achieved by increasing the filtration to 2 mm. zinc or copper and by increasing the focus-skin distance. A practically homogeneous radiation is reached by a filtration with 1 mm. zinc, the further increase serving only to decrease the intensity. The decrease of intensity by increasing the skin-focus distance and size of field influences the depth dose favorably, as the effective dose on the tumor is increased, while the skin dose remains unchanged.Under the above-quoted conditions the time necessary for the application of 1 1/2–2 H (75–100 r) is about two hours. During each single treatment a field of 400 sq. cm. is given from 75 to 100 r, two such treatments being administered daily. In carcinomas of the female genitalia four fields are irradiated, two each day, for five or six weeks. The total skin dose of each field is larger than 2,100 r, as the radiation penetrating from the opposite side cannot be neglected. The total dose is more than three times larger than the skin erythema dose, when a large single dose with large hour-intensity is applied. The effective dose on the tumor is 8,400 r, thirteen times as large as the skin erythema dose.Article HistoryPublished in print: Sept 1931 FiguresReferencesRelatedDetailsRecommended Articles RSNA Education Exhibits RSNA Case Collection Vol. 17, No. 3 Metrics Altmetric Score PDF download
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