X-RAY PHOTOGRAPHY

Hokitika Guardian, 5 April 1930, Page 3

X-RAY PHOTOGRAPHY

VALUE. OF DIAGNOSIS

WELLINGTON, April 2

Statements made in the Arbitration Court by Dr S. H. Rliind that X-ray photography was useless as an aid to diagnosis were replied to yesterday, by a prominent Wellington medical man.

He said that it would be difficult to imagine modem surgery or any branch of medicine -being deprived of the services of the X-ray. That gave some indication of its value. It was admitted to be only an aid, but it was not used for diagnoses relating to every part of the body. “The X-ray examination is purely physieial and an aid to the ordinary physicial examinations carried out by doctors in their diagnoses” lie said. “If properly carried out ,it. is a photographic record of physical conditions, and, therefore, in a true sense of the term .it cannot lie, hut under certain conditions it can quite well give faulty impressions. There (are two factors governing the usefulness of X-ray evidence. First, there is the consideration of all the physical details that enter into the taking of the radiograph, and, secondly, there is the personal factor of the interpretation of the radiograph. The first factor of the physicial. details has become almost perfected. The second factor depends on personal experience and judgement. “It might be pointed out that the co-ealled X-ray protograpli is not really a photograph in the ordinary sense of the term. It is a record of physical properties .in terms of differential density. Bones arc made up of hard substances, and they therefore absorb most of the X-rays and leave a dense shadow on the plate, fl ho muscles and internal organs are composed of substances much less dense; they allow more.' X-rays to penetrate them and cast very much less density on the nlate. Any condition affecting the density of the bones, either through injury or disease, will be reflected in the X-ray image.

“Modern methods can allow us to determine many changes that occur nbo in the sott tissues. It must he ftrtnly emphasised that these radiographs are purely part of.,medical evidence, jurt in the same way medical evidence obtained by other means. They are therefore entirely useless without proper interpretation.”