Radiology of the urinary tract: some physiological considerations. Annual oration in memory of John S. Bouslog, M.D., 1890-1973.

This paper reviews some of the fundamental technical and diagnostic problems in clinical uroradiology, such as (a) the reason for the obstructive nephrogram; (b) why high-dose urography gives better studies than low-dose; (c) why the Trueta phenomenon has not been demonstrated in man; (d) the case for an intrarenal arterial collateral pathway via the pericalyceal network (these vessels can be demonstrated in man and must not be misinterpreted as tumor vessels or vascular malformations). One of the most baffling problems sometimes occurs with the sudden partial block of a single segmental vessel: the kidney ceases to excrete urine and eventually becomes atrophic even though some excretory function returns. To date, there is no satisfactory explanation for this course of events.