Hydronephrosis index: a new method to track patients with hydronephrosis quantitatively.

OBJECTIVES: To show that hydronephrosis (HN) can be tracked by the quantitative reproducible hydronephrosis index (HI) and that HI is useful for serial ultrasound (US) studies to determine whether HN is improving or deteriorating. METHODS: We found 60 hydronephrotic kidneys in 46 study patients. The other 32 kidneys were normal or absent. Serial US studies were performed more than 1 month apart over a 3-year period. Hydration was maximized with oral fluids. Cases ranged in age from 2 days to 13 years. We determined HI as follows: Operators outlined the perimeters of the kidney and dilated renal pelvis in the maximal longitudinal view. Respective areas were automatically calculated. We obtained HI by outlining the area of the kidney and separately outlining the area of the dilated renal pelvis within the kidney. We calculated HI percentage as 100 x (Total area of kidney minus area of dilated pelvis and calices)/(Total area). This percentage calculation represents the renal area determined reproducibly in a standardized fashion as if the calices were not there and is recorded as a dimensionless number. RESULTS: Hydronephrosis for 30 of 60 kidneys (50%) showed decreasing HN, and for 17 of 60 kidneys (28%) showed increasing HN. In 13 of 60 (22%) HN was unchanged. Statistical analysis showed that HI was determined with an objectivity of 99.8%. CONCLUSIONS: Hydronephrosis is the most common abnormality detected with ultrasonography. The quantitative method for HI provides a reproducible measure of HN. With longitudinal studies, the quantitative HI shows whether HN is improving or deteriorating.

Mechanical thrombectomy for treatment of postoperative venous obstruction in pediatric patients.

Four critically ill neonates and two small children have undergone a total of nine postoperative cardiac catheterizations involving mechanical thrombolysis and early post-procedure abciximab for significant venous thrombus obstruction. Bacterial infection was associated in five patients and suspected in a sixth. These procedures achieved near normal venous flow pattern and subsequent long-term seemingly normal central veins in the three survivors (by ultrasound in two patients and by autopsy in the other who subsequently died of sepsis). Three of the six patients died; one from sepsis, one from intracranial bleeding at the site of prior unknown bleeding, and one with renal failure. Mechanical thrombolysis is a feasible additional treatment for critically ill infants and children who either fail to respond to medical treatment or need a prompt intervention, such as reopening of an intracardiac fenestration in the early postoperative period. Such treatment may be particularly valuable in patients who are bacteremic and are losing considerable fluids and proteins in the setting of apparent acute thoracic duct occlusion with thrombus in the superior vena caval system and the innominate vein in particular. Mechanical thrombolysis and supplemental support with agents such as abciximab may help keep these vessels open and decrease the thrombus and bacteria load in critically ill infected patients, such that continued standard medical support can result in full recovery.