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Diagnosis of obstruction in dilated ureters.

MOST, IF NOT all, of the currently used methods of assessing ureteric obstruction have major disadvantages. For a true assessment both the pressure and the flow must be known, and on this basis a new test has been developed using perfusion at a known flow rate. Over 70 studies have been performed with this technique and it has been found valuable. It provides an objective assessment of minor degrees of ureteric obstruction and allows a rational approach to the operative management. Introduction To OUR KNOWLEDGE, John Hunter did not make a special study of the problem of ureteric obstruction, but at least one of his preparations showed that he was aware of it. Of an upper ureter and renal pelvis (Specimen P.303) from a 53-year-old man who died of prostatisnm and bladder stone Hunter says 'the pelvis is much dilated; the ureter is less so, but, about an inch from its commencement, makes two abrupt turns . . . the passage of urine from the pelvis must have been greatly obstructed.' In gross obstruction of the upper urinary tract there are usually obvious symptoms and signs and adequate evidence of obstruction both clinically and radiographically; the diagnosis presents no problem at all. I wish to discuss a quite different situation that is, quiestionable or equivocal obstruction. Here the isymptoms are few, often those of a single urinary tract infection. Intravenous pyelograms show upper traot dilatation, often with a narrowed area at the pelviureteric or ureterovesical junction. There may be a little delay in the appearance and draining of the contrast medium and the calyces may be a little blunted. Renal function tests may show marginal impairment. In all cases under discussion vesicoureteric reflux has been excluded. I believe that operations on dilated ureters have been widely undertaken without adequate evidence of obstruction, and because of this the results have often been disappointing. An effort should be made to define the extent of the obstruction and to operate accordingly; it is only in this way that we will avoid superfluous and often hazardous surgery. Often the only obvious abnormality is dilatation of the ureter on an X-ray and it is tempting to make a diagnosis on this alone as we all