CLINICAL CONFERENCE Some Pitfalls in Pediatric Radiology

Thorough familiarity with normal variations and insignificant anatomic deviations is essential to the practice of clinical pediatrics. Through constant observation and experience differentiation from disease becomes possible. In radiology this same problem exists and is probably more significant, as roentgenograms record only the situation as of a particular moment-an inherent weakness of the method. In radiology many standard procedures are established so that results may be duplicated and progress of disease evaluated. Deviations from standard procedures often simulate disease. In addition to this pitfall, there are many anatomic variations to plague the radiologist at the time of interpretation. The following are examples of roentgenograms which have simulated disease but upon investigation proved to be normal: 1. The gaseous pattern in the infant differs from the adult. Ordinarily, we are taught that gas in the small bowel suggests obstructive ileus. In the infant under 2 years of age, gas in the small bowel is normal. After this age or after the child begins to walk the gas in the small bowel disappears and its presence then assumes significance. Improved intra-abdominal circulation, better co-ordination of diaphragmatic movements is responsible for greater absorption of gas in the small bowel after this age (Fig. 1). Large amounts of air in the stomach are not necessarily due to obstruction. A very hungry baby will swallow huge amounts of air to a point of distending the abdomen. We know this occurs and is without significance, as we use this phenomenon for diagnostic pyelography. In this procedure, the ravenously hungry child is given a bottle of formula after the intravenous or intramuscular injection of contrast material is administered.