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A B Kurtz

Publications and source records attributed to A B Kurtz.

At least 19 recordsLinked to original sources
PubMed1992

Analysis of trough serum growth hormone concentrations: comparison of an immunoradiometric assay and a sensitive ELISA for growth hormone.

OBJECTIVES: We compared a sensitive assay for GH (ELISA) with a conventional immunoradiometric (IRMA) assay with particular reference to the oscillatory activity detected by Fourier transformation and the estimation of trough concentrations using occupancy analysis. DESIGN: Eight healthy adult male volunteers underwent 24-hour profiles during which samples were drawn at 20-minute intervals. Samples were analysed by an ELISA and an IRMA system. MEASUREMENTS: The 24-hour serum GH concentration profiles were subjected to Fourier transformation and to occupancy analysis. RESULTS: No additional GH periodicities could be determined in the ELISA data other than the well documented 180-200-minute periodicity. Median observed concentrations (OC) at 5% occupancy were 0.035 mU/l (range 0.004-0.22) for the ELISA and 0.035 mU/l (range 0.001-0.50) for the IRMA. For all OC parameters, 5, 50 and 95%, there was a good correlation between the ELISA and IRMA systems. The mean difference (bias) between the ELISA and IRMA were -0.05, -0.28 and -1.40 mU/l at OC values of 5, 50 and 95% respectively and the standard deviations of the difference at the same OC values were 0.10, 0.50 and 1.61 mU/l. CONCLUSION: Although there is a qualitative improvement on visual inspection of individual 24-hour serum GH profiles obtained using the ELISA system, there is little additional information gained in terms of pulse periodicity or occupancy analysis.

Adult↗
PubMed1992

Gas within the endometrial cavity at postpartum US: a normal finding after spontaneous vaginal delivery.

In the puerperium, the detection of gas within the endometrial cavity at ultrasound (US) has been commonly taken to indicate endometritis. Of 70 clinically healthy women in whom US was performed after uncomplicated spontaneous vaginal delivery, 13 (19%) had evidence of gas in the endometrial cavity within the first 3 postpartum days (mean, 37 hours; range, 25-59 hours) and five (7%) had such evidence in the 3rd week after delivery (mean, 2.4 weeks; range, 2.1-2.9 weeks). Gas was seen in the endometrial cavity on at least one occasion during the first 3 postpartum weeks in 15 (21%) of these apparently healthy women; in no case did clinical evidence of endometritis develop. From these observations, the authors believe that gas detected within the endometrial cavity is not, in and of itself, suggestive of endometritis, and that such a finding should be considered normal, at least until the end of the 3rd postpartum week.

Endometritis↗
PubMed1992

Twin pregnancies: accuracy of first-trimester abdominal US in predicting chorionicity and amnionicity.

A first-trimester transabdominal ultrasound (US) study was performed on twin pregnancies to determine the utility of US in predicting chorionicity and amnionicity. Among 85 dichorionic-diamniotic (DC-DA) twin pairs, a thick membrane was present in 78 (92%). Four of the DC-DA cases without a thick membrane had two distinct placental sites, allowing 82 DC-DA pregnancies (96%) to be predicted. Among 16 monochorionic-diamniotic (MC-DA) twin pairs, a thin membrane was present in 14 (88%). None of the four monochorionic-monoamniotic (MC-MA) cases had an identifiable membrane. The lambda sign had no value in this evaluation and was actually misleading, while a thick membrane or the identification of two separate placentas was always predictive of DC-DA twinning. However, a thin membrane, while usually predictive of an MC-DA pregnancy, did not exclude a DC-DA gestation. When no membrane is present, an MC-MA gestation is probable; however, a diamniotic pregnancy may still be present, and further evaluation is suggested.

Amnion↗
PubMed1992

Can detection of the yolk sac in the first trimester be used to predict the outcome of pregnancy? A prospective sonographic study.

Recent reports have indicated that identification of the yolk sac should precede the detection of the embryo in a normal first-trimester sonographic examination and that failure to visualize a yolk sac strongly suggests an abnormal intrauterine pregnancy. A first-trimester prospective study was performed in 163 normal and 49 abnormal consecutive singleton gestations. All women were examined both abdominally and transvaginally, with pregnancy outcome determined by delivery of a normal infant or a spontaneous abortion. The yolk sac was analyzed in all patients in whom an embryo was not identified (n = 76). When the yolk sac was identified, the following was found: by the abdominal approach with the mean sac diameter (MSD) less than 27 mm (n = 15), nine gestations were normal and six were abnormal, and by the transvaginal approach with the MSD less than 18 mm (n = 13), seven gestations were normal and six were abnormal. The presence of a yolk sac was not consistently predictive of a normal early pregnancy. When the yolk sac was also not identified, the following was found: abdominally with the MSD less than 27 mm (n = 41), 19 gestations were normal and 22 were abnormal, and transvaginally with the MSD less than 18 mm (n = 11), six gestations were normal and five were abnormal. Absence of the yolk sac was not consistently predictive of a spontaneous abortion. When using the MSD range (20-27 mm abdominally and 7-16 mm transvaginally), over which the yolk sac but not the embryo should be identified sonographically, the yolk sac was again not consistently visualized. On abdominal sonograms, the yolk sac was present and absent in three and 10 patients, respectively, for both normal and abnormal pregnancies. On transvaginal sonograms, the yolk sac was present and absent in seven and five normal gestations and in six and four abnormal gestations, respectively. The results of this study suggest that detection of the yolk sac in the first trimester is not an early predictor of pregnancy outcome.

Female↗
PubMed1992

Creutzfeldt-Jakob disease in recipients of human growth hormone in the United Kingdom: a clinical and radiographic study.

In the past 3 years there have been five further cases, in addition to one case reported in 1985, of Creutzfeldt-Jakob disease in recipients of human growth hormone in the United Kingdom. The clinical findings of two of these cases are described, demonstrating a typical presentation with a predominantly cerebellar syndrome at onset which is not commonly a presenting feature of sporadic Creutzfeldt-Jakob disease. In one case a 99mTc hexamethylpropylenamine single photon emission tomographic scan showed marked impairment of tracer uptake in the basal ganglia and cerebral cortex at a time when the clinical picture was predominantly cerebellar. This technique may be useful in early diagnosis. In the other case post mortem examination of the brain showed prominent amyloid deposition in the cerebellum, which has not been described previously in pituitary-hormone related Creutzfeldt-Jakob disease. The previously published cases of growth hormone-related Creutzfeldt-Jakob disease are reviewed and reasons for the particular clinical pattern seen are discussed.

Adult↗
PubMed1991

Endoluminal sonography of the urinary tract: preliminary observations.

Endoluminal sonography of the urinary tract was performed by using endoluminal ultrasound transducers contained within 2-mm-diameter catheters. The catheters were inserted into the urinary bladder via the urethra and advanced into the ureters and renal pelvis under cystoscopic control; then, cross-sectional images of the bladder, ureters, and renal pelvis were obtained. Two dogs and seven human patients were studied. In one dog, a 4.5-mm pseudopolyp, which was surgically created in the bladder wall, was successfully imaged; in the other, stones 2 mm or larger inserted into the bladder were identified. Of the seven patients, sonography showed stones embedded in the renal parenchyma (one patient) and the mucosa of the distal ureter (one patient). These were ultimately confirmed by their eventual removal. In a third, sonography showed a tumor of the distal ureter and identified the depth of the tumor. This was confirmed by biopsy. In a fourth, sonography clearly showed a crossing vessel as the cause for narrowing of the proximal ureter. In a fifth, sonography showed that the cause of a ureteral stricture was idiopathic. In the last two cases, sonography did not reveal a cause for hematuria. In these last three cases, negative sonographic results were confirmed by direct ureteroscopic examinations and follow-up studies. Our observations based on this limited study suggest that endoluminal sonography is a useful procedure for diagnosing diseases of the urinary tract. Further study is warranted.

Adult↗
PubMed1991

Imaging the gallbladder: a historical perspective.

After Wilhelm Conrad Roentgen's discovery of the X-ray in 1895, it was initially thought that gallstones could not be visualized. Surgeons relied solely on the clinical examination to detect biliary disease. Today, no evaluation of the gallbladder would be complete without the performance of an imaging study. Radiology has gone through several eras in the imaging of gallstones. The plain film era, 1895-1924, was characterized by techniques that improved soft-tissue detail, allowing better detection of radiopaque stones. The contrast media era, 1924-1960, was initiated by the invention of IV cholecystography. In 1925, oral cholecystography was developed. During the era of expanding technology, 1960-1979, percutaneous transhepatic cholangiography, scintigraphy, and sonography came into use. The therapeutic era began in the 1980s.

Cholecystography↗
PubMed1991

Endoluminal gynecologic ultrasound: preliminary results.

Specially developed high-resolution real-time ultrasound transducers (12.5 and 20 MHz) on the tip of endoluminal catheters were inserted into the endometrial canal to evaluate the usefulness of this approach. Uterine abnormalities, most confirmed by biopsy, surgery, or both, were detected in 12 patients, including submucosal myomas, nabothian cysts, endometrial polyps, synechiae, and endometrial and cervical carcinoma. In one case the catheter was directed under hysteroscopic guidance into a fallopian tube, demonstrating its potential usefulness in this region. In 4 of the 12 cases in which a hysterectomy was performed, an in vitro ultrasound examination of the organ was performed, which confirmed the initial in vivo ultrasound impressions. Anatomic cross-sectional slices of the uterus resulted in excellent correlation with the ultrasound findings. These preliminary results suggest that this new sonographic procedure will become an important diagnostic tool, supplementing abdominal and endovaginal ultrasound approaches.

Adult↗
PubMed1991

Prospective comparison of vaginal and abdominal sonography in normal early pregnancy.

Vaginal and abdominal sonography were prospectively compared in 309 consecutive pregnancies of which 175 were normal. Two sonographic criteria of normal were analyzed: (1) the presence of an embryo compared with average gestational sac size and (2) the presence of embryonic cardiac activity compared with crown-rump length. Vaginally, 100% (160/160) of embryos were visualized when the average sac diameter was greater than or equal to 12 mm. Abdominally, an embryo was noted in 99.2% (123/124) of gestational sacs greater than or equal to 27 mm. Vaginal sonography revealed cardiac motion in all embryos of greater than or equal to 5 mm (149/149 cases); abdominal sonography revealed cardiac activity in 100% (132/132) of embryos with a crown-rump length of greater than or equal to 9 mm. One-third of normal embryos less than 5 mm crown-rump length did not demonstrate cardiac activity. The study demonstrates through objective comparison that vaginal sonography is superior to abdominal sonography for detection of an intrauterine embryo and its cardiac activity before 8 menstrual weeks. The diagnosis of embryonic demise should not be made by vaginal sonography in embryos measuring less than 5 mm crown-rump length without a heartbeat, and an empty gestational sac of less than 12 mm average diameter should not be diagnosed as blighted ovum by vaginal scans. In these cases follow-up vaginal sonography is suggested.

Abdomen↗
PubMed1991

Detection of retained products of conception following spontaneous abortion in the first trimester.

A retrospective analysis was performed to determine whether ultrasound could reliably rule in or out retained products of conception (POC) in women after first-trimester spontaneous abortions (miscarriages). Ninety-seven first-trimester pregnancies with pathologically proven results from dilatation and curettage (D&C) were studied within 7 days of ultrasound examination (60% within 2 days), either by the abdominal or a combination of abdominal and vaginal approaches. Cases were eliminated if there was clinical evidence of a spontaneous evacuation of POC during the interval between the ultrasound and the D&C. POC were diagnosed only if chorionic villi were evident pathologically. The pertinent ultrasound findings were related to the endometrium (thickness, echogenicity, a gestational saclike structure or a space-occupying collection). The results indicated that ultrasound could correctly diagnose POC in all of the cases by detecting a gestational sac or collection (77 cases), or a thickened endometrium of greater than 5 mm (6 cases). Ultrasound was less reliable in ruling out retained POC. When only a thin endometrial stripe of less than 2 mm was present, there was little likelihood of having POC (1 of 7 cases) with a moderately thick endometrium of 2 to 5 mm not diagnostic. Vaginal ultrasound added little new information and failed to change the ultrasound interpretation.

Abortion, Incomplete↗
PubMed1991

Biliary sonography.

Ultrasonography is a dynamic, powerful, and readily available tool in the armamentarium of biliary diagnosis. The use of this modality is indicated in the initial work-up of jaundice since ultrasonography is exquisitely sensitive to the presence of intrahepatic or extrahepatic biliary dilatation. The liver and pancreas may be screened for focal masses. In acute right upper quadrant pain, ultrasonography can assess the organs residing in this area, often yielding significant information in the diagnosis of gallbladder disease. Newer modalities such as color Doppler may add specificity and reliability to sonographic findings.

Biliary Tract↗
PubMed1990

Anterior protrusion of retroperitoneal processes. A mimic of lesser sac or gastrohepatic masses.

The space between the left lobe of the liver and the lesser curvature of the stomach normally contains intraperitoneal structures. These include the gastrohepatic recess of the greater peritoneal cavity, the medial recess of the lesser sac and the interposed gastrohepatic ligament. An anterior protrusion of retroperitoneum can project into this space, dorsal to the posterior reflection of the medial compartment of the lesser sac. Tumors that extend into this fossa are anterior and medial to the fundic and upper body region of the stomach. These tumors may cause confusion regarding their origin if the radiologist is not aware of the existence of this retroperitoneal protrusion. Between 1982, and 1986, 183 patients with pancreatic cancer were hospitalized at our institution, 63 of whom had computed tomography (CT) scans of the abdomen. Four of these patients (6.3%) demonstrated direct tumor extension anterior to the stomach. During this same period, four large benign retroperitoneal tumors also exhibited this finding. Masses in the gastrohepatic interval between the liver and stomach can be extensions of retroperitoneal processes and should not be assumed to represent intraperitoneal involvement.

Diagnosis, Differential↗
PubMed1990

Prospective comparison of computed tomography and duplex sonography in the evaluation of recently inserted Kimray-Greenfield filters into the inferior vena cava.

A prospective comparison of contrast-enhanced computed tomography (CT) and duplex sonography (DS) was performed to examine the Kimray-Greenfield filter in the inferior vena cava (IVC) in the immediate postoperative period. Fourteen patients were studied for five complications: IVC thrombosis, malpositioning, pericaval hematoma, filter angulation, and prong perforation. Our results found CT to be more efficacious because it was a) able to evaluate more patients with fewer technically inadequate scans and b) more definitive in all categories. However, when visualized, DS was as accurate as CT in the evaluation of thrombosis.

Humans↗