Asymptomatic and regressing ALM are best managed conservatively ("watchful waiting") while symptomatic ALMs require surgery. Further studies are necessary to determine the ideal timepoint for intervention for non-regressing ALM.

The majority of shunt dysfunctions can be easily diagnosed by puncturing the Rickham reservoir with a fine needle and estimating the intracranial pressure. Experience has, however, shown that definite shunt dysfunctions can be missed by this method. These limitations of the technique are better understood by constructing a model which enables us to simulate the pressure and flow situation in a ventricular drainage system. This experimental model has shown that in cases of partial proximal or distal blockage, the flow through the shunt system is significantly diminished but not totally stopped, and the pressure reading may thus be normal. In these cases, the shunt should be revised on the basis of clinical evidence of dysfunction.

This is a description of a ureteric replacement operation employing a modified Culp-de-Weerd method for the ileopelvic segment of the ureter combined with a Cohen ureteric reimplantation. This operation was carried out in a 2-month-old infant with a stenosis of the left ureter. 7 months postoperatively the left kidney is normal as far as its anatomy and function is concerned.