The use of Rontgen rays has a distinct role in certain stomach cases, especially in the diagnosis of the presence or absence of metallic bodies in the oesophagus or stomach. While the Murphy button was being used in gastroenterostomy it very frequently fell back into the stomach and remained there, in some cases setting up irritation or ulceration. I have been consulted in several such cases, and by means of skiagraphy have been able to localise the foreign body preparatory to its removal. I have also found skiagraphy of very great help where foreign bodies have been swallowed in ascertaining their position in the oesophagus or stomach; for instance, coins and dentures are thus easily localised both before and after entering the stomach; and nails, pins, needles, and suchlike bodies can be readily seen in the stomach, whence they can be removed by gastrotomy.
A further use has been made of the X rays to ascertain the size of the stomach and the situation of the pylorus by the use of the screen with the patient in the erect posture, after letting him swallow keratin-covered capsules containing bismuth, the covering of which is not dissolved by the gastric juice.
Dr. Dalton and Mr. Reid (1) have made use of a flexible tube containing bismuth, to show the outline of the stomach.
The digestive power of the stomach, an exact estimate of which is essential in the treatment of disorders of metabolism and diseases of the intestine, has hitherto been measured by means of Ewald\s test breakfast, with the subsequent use of the stomach-tube ; or by the iodine or salol reaction of the urine, as suggested by Sahli; or by estimating the reaction of the stomach contents on coagulated albumen contained in Mett's tubes. Dr. Schwarz has recently proposed a very simple method of examining the digestive power of the gastric juice, at least so far as the digestion of connective tissue is concerned. He uses subnitrate of bismuth, a substance which is well known to cast a black shadow when the X rays are directed upon it. He makes the patient swallow a large pill of about one third or half an ounce of the powdered subnitrate, enclosed in an envelope of connective tissue obtained from the appendix vermiformis of an animal such as the sheep, goat, or ox. If the abdomen of the patient is exposed to the X rays a short time after swallowing the pill a deep black spot of about the size of a farthing is seen at the bottom of the stomach. As soon as the coating of connective tissue is digested the powder is scattered and the contents of the stomach are well mixed with the powder, after which a fainter but extensive shadow, which gives the contour of the entire organ, is cast on the photographic plate or on the fluorescent screen. This is the case in seven hours after ingestion of the pill in healthy stomachs. If the digestion is affected, as is the case in gastroptosis, deficiency of acid, pyloric disease and cancer, the black spot remains visible for a longer time-nine, eleven, or even twenty hours. If the contents of the stomach are digested too quickly, as in hyperacidity, the black spot disappears in from two to five hours. The method is very simple and causes no serious inconvenience to the patient.
Electric illumination may sometimes be useful in demonstrating the size of the stomach and in showing the position of a tumour, which appears as a dark patch in a light field. It is easily applied by letting the patient drink sufficient water when the stomach is empty to moderately fill it. A bougie is then passed with a small electric lamp near its extremity. It is best used in the erect posture and in a dark room.