A caesium 137 teletherapy unit for use at a source-to-skin distance of 35 cm.

A caesium 137 unit containing 1300 curies in a source of diameter 1 1⅙ in. has been described. The unit gives rectangular fields from 5 × 5 to 20 × 20 cm at 35 cm. The absorbed dose-rate on the skin from the unit varies from 38 to 40 rads/minute as the field size is varied from 4 × 4 to 20 × 20 cm. The isodose distributions are similar to those produced from a 400 kV machine for large fields. For small fields, the caesium gives a higher depth dose. The unit appears to be a useful radiotherapeutic tool.

[1]  W. Eastwood.  Fission product caesium 137 for use in telecurie units. , 1954, The Journal of the Faculty of Radiologists. Faculty of Radiologists.

[2]  J. Haybittle,et al.  An improved iridium-192 teletherapy unit. , 1953, Acta radiologica.

[3]  H. E. Johns,et al.  Depth dose data, 150 kVp to 400 kVp. , 1952, The British journal of radiology.

[4]  H. E. Johns,et al.  1000 Curie cobalt units for radiation therapy. I. The Saskatchewan cobalt 60 unit. , 1952, The British journal of radiology.

[5]  J. Haybittle,et al.  Radio-iridium teletherapy. , 1950, Acta radiologica.

[6]  H. Miller,et al.  A 50 curie cobalt 60 teletherapy unit. , 1955, The British journal of radiology.

[7]  F. Spiers,et al.  A cobalt 60 beam unit with a source-skin distance of 20 cm. , 1955, The British journal of radiology.