Dr. Den Hoed setting up a Philips X-ray unit with insulated high voltage cables. Spaarnestad Photo 1940.
In 1932, Siemens installed a wall stand with insulated high voltage supply. The Philips safety stand also came into use. In these machines, the high voltage was connected with insulated cables, as can be seen in the photo. The open cables on the ceiling were no longer used. The radiotherapy department compared both machines in practice.
The X-ray department. A 15 cm thick leaded wall protects the staff when operating the controls.
On the wall of the control room, parts of the improved safety measures can be seen. Indication lights warn of the operation of the various pieces of equipment in the room. Simultaneous irradiations still take place in one room. On the right of the door a radiation clock is fixed to the wall, a sort of mechanical egg timer which rings when the defined radiation time is reached.
1940. X-ray irradiation with compression. (Spaarnestad Photo)
Compression was sometimes used to reduce the blood flow to the area to be irradiated, by which the effect of the radiation would be enhanced. Compression was also used to reduce the distance between the skin and deeper lying tumours by which the limited depth penetration of the X-rays could be better utilized.
In 1932 the company Almara in Amsterdam donates a so-called Grenzstrahl machine manufactured by Bucky. This machine is designed for irradiation of the skin with soft X-ray irradiation, at a voltage of around 10,000 Volt. Dr. den Hoed undertakes biological experiments with this machine.