A B S T R A C T Urinary excretion of cyclic adenosine 3',5'-monophosphate (3',5'-AMP) was tested in normal subjects and patients with pseudohypoparathyroidism, idiopathic hypoparathyroidism, surgical hypoparathyroidism, and pseudopseudohypoparathyroidism under basal conditions and after a 15 min infusion of purified parathyroid hormone. Basal excretion of the nucleotide was less than normal in the patients with hypocalcemic disorders and greater than normal in pseudopseudohypoparathyroidism. Parathyroid hormone caused a marked increase in excretion of 3',5'-AMP in all subjects except those with pseudohypoparathyroidism; nine patients with this disorder did not respond to the hormone and four showed a markedly deficient response. Radioimmunoassay showed that parathyroid hormone circulated in increased amounts in plasma from patients with pseudohypoparathyroidism and became undetectable when serum calcium was increased above 12 mg/100 ml. Suppression of parathyroid hormone secretion by induction of hypercalcemia did not alter the deficient response to exogenous hormone. The results indicate that: (a) parathyroid hormone circulates in abnormally high concentrations in pseudohypoparathyroidism and secretion of the hormone responds normally to physiological control by calcium; (b) testing urinary excretion of 3',5'-AMP in response to infusion of purified parathyroid hormone appears to-be an accurate and sensitive index for establishing the diagnosis of pseudohypoparathyroidism; and (c) the metabolic defect of the disorder can be accounted for by a lack of or defective form of parathyroid hormone-sensitive adenyl cyclase in bone and kidney.

No abstract

award for a scientific exhibit at the 1990 RSNA scientific assembly.

A study of 28 patients with surgically proved testicular tumors was performed to determine the appearance at color Doppler ultrasound (US) scanning. There was a general correlation of tumor size and vascularity. Twenty of 21 (95%) tumors larger than 1.6 cm were hypervascular. Six of seven (86%) tumors smaller than 1.6 cm were hypovascular. One small, 1.1-cm-diameter seminoma was hypervascular, and one 2.8-cm-diameter seminoma was hypovascular. The histologic findings of the tumor did not correlate with the vascularity of the lesion as seen at color Doppler US. Resistive indexes ranged from .476 to 1.0 (mean, 0.70). Peak systolic velocities ranged from 8.4 cm/sec to 64.9 cm/sec (mean, 9.8 cm/sec). Venous flow was detected in eight tumors. The gray-scale findings, as well as history and physical examination findings, correctly suggested a neoplasm in all cases. The findings at color Doppler US were prospectively interpreted as indicative of neoplasm in 27 cases and as indicative of inflammation in one case. The authors conclude that color Doppler US scanning has only a limited role in the evaluation of testicular tumors.

A study of 45 patients with 51 cases of hemiscrotal inflammatory disease was done to determine the color Doppler ultrasonographic appearance of scrotal inflammatory disorders. The diagnosis was ultimately established by means of appropriate response to antibiotic treatment (47 cases) or surgery (four cases). In all cases, there was evidence of hyperemia: an increased number and concentration of detectable vessels in the affected portion of the scrotum. In 17 cases, the gray scale images were normal, and the only evidence of inflammation was the presence of hypervascularity. Abnormally decreased epididymal vascular resistance was detected in 14 cases of epididymitis; abnormally decreased testicular vascular resistance was detected in six cases of orchitis. Spontaneous venous flow was present in 18 patients. The authors conclude that color Doppler can demonstrate the hyperemic response to scrotal inflammatory disease and that, in the proper clinical setting, it can supplement the gray scale findings and increase diagnostic confidence.

No abstract

Recent reports have indicated that hyperechoic renal cell carcinomas (RCCAs) are more frequent among small cancers and that small cancers are being detected more frequently. To determine whether these trends have resulted in a change in the frequency of detection of hyperechoic RCCA and, in particular, in the frequency of RCCA mimicking angiomyolipomas (AMLs), the sonographic features of 90 pathologically proved RCCAs in 82 patients were retrospectively reviewed and correlated with tumor size. Tumor echogenicity was compared with that of normal renal parenchyma and classified as hypoechoic, isoechoic, slightly hyperechoic, or markedly hyperechoic. Thirty-one tumors were 3 cm in diameter or less, and 59 were larger than 3 cm. Ten (32%) of the tumors 3 cm in diameter or less were markedly hyperechoic and mimicked AMLs, whereas only one (2%) of the tumors larger than 3 cm had this appearance (P < .001). Eleven of the 90 tumors (12%) were markedly hyperechoic. Twenty-four (77%) of the small tumors were either slightly or markedly hyperechoic, compared with 19 (32%) of the larger tumors (P < .001). Because of the increased detection of small RCCAs in recent years, the number of hyperechoic cancers and the number of cancers mimicking AMLs have increased.

A total of 103 consecutive patients with suspected biliary obstruction were studied using both computed tomography (CT) and ultrasound (US) to evaluate the relative accuracy of the methods. In 47 patients with confirmed obstruction, CT and US were comparable accurate in differentiating obstruction from nonobstruction. The precise level of obstruction was identified by CT in 88% and by US in 60%; the cause of obstruction was accurately predicted by CT in 70% and by US in 38%. Both methods detected useful additional information, such as cholelithiasis or retroperitoneal adenopathy. The authors use US as a screening examination; if there is doubt about the level and cause of sonographically demonstrated obstruction, CT has proved to be an accurate means of further evaluation.