Ridat Company, the London based manufacturer of thermoforming machinery, in partnership with RCS Thermoforming Company, has launched a new vacuum forming machine to produce large Beam directional shells.

Presently, these transparent plastic shells are used to immobilise and position the patients comfortably so that the external beam radiotherapy can be planned and given in a precise and repeatable manner. Use is limited to the head and neck.

The larger Thorax shell extends from the cheek to the diaphragm, could be made on the model 3624 Medivac and used for patients requiring treatment of the oesophagus.

The Ridat machine has a forming area of 36” by 24” (914mm x 610mm) and is also fitted with a reducing aperture for the smaller moulds.

To make the shells, an impression of the patient is first taken and from this a plaster positive cast is made.

The cast is placed in the Ridat machine and plastic film is heated and drawn drawn down over the cast by applying vacuum