During the past several years there has been an increasing use of small unrectified x-ray machines by dermatologists. This type of equipment has been used over a period sufficiently long to permit evaluation, and we feel that a critique would be of value to dermatologists contemplating purchasing new machines in the near future.
The several types of x-ray apparatus available for treatment may be classified in the following groups: full wave rectified, either mechanically or by means of four valve tubes; half wave suppressed by means of one or two valves, and half wave suppressed (so-called unrectified) by means of the x-ray tube itself. An understanding of what rectification is and why it is employed is necessary to an intelligent understanding of the problem. There is still a rather widespread impression among both radiologists and dermatologists that a machine with an unrectified circuit is unsuitable for treatment. This impression is
GINSBERG JE, LANDAUER RS. UNRECTIFIED X-RAY MACHINES FOR DERMATOLOGIC USECLINICAL CONSIDERATIONS. Arch Derm Syphilol. 1939;40(1):53–58. doi:10.1001/archderm.1939.01490010056007