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R H Gottlieb

Publications and source records attributed to R H Gottlieb.

34 records · Page 2Linked to original sources
PubMed1996

The prostate: decreasing cost-effectiveness of biopsy with advancing age.

RATIONALE AND OBJECTIVES: The purpose of this study was to determine the cost-effectiveness of prostate biopsy at different excess prostate-specific antigen (PSA) levels as a function of age. METHODS: Medical decision analysis was performed with standard software (SMLTREE) to determine marginal effectiveness in quality adjusted life years (QALYs) and marginal cost-effectiveness in dollars per QALY of immediate prostate biopsy at different excess PSA levels between 0 ng/mL and 20 ng/mL. The probability of clinically significant cancer with a positive biopsy (pD+Bx+) was assumed to decrease with age from 1.0 at age 50 to 0.2 at age 70. Costs were based on charges at our hospital and were considered over a 2-year time frame. RESULTS: With our base case assumptions there was a decrease in QALYs and an increase in costs doing an immediate prostate biopsy at all excess PSA levels between 0 ng/mL and 20 ng/mL, compared with not biopsying the prostate at > or = 70 years. Doubling pD+Bx+ from 0.2 to 0.4 in the 70-and-older age group resulted in a small increase in QALYs in biopsying the prostate at excess PSA levels between 0 ng/mL and 20 ng/mL. However, the marginal cost-effectiveness of prostate biopsy was very high, ranging from $275,000/QALY biopsying at an excess PSA level of 0 ng/mL to $68,000/QALY biopsying at an excess PSA level of 20 ng/mL. This compared with it being more effective and less costly to biopsy at all excess PSA levels > or = 0 ng/mL in 50-year old patients. CONCLUSION: Immediate prostate biopsy is not cost-effective and can be detrimental in patients > or = 70 years of age at all excess PSA levels between 0 ng/mL and 20 ng/mL.

Aged↗
PubMed1996

Clinical evaluation of prostate biopsy parameters: gland volume and elevated prostate-specific antigen level.

PURPOSE: To determine whether excess prostate-specific antigen (PSA) improves the accuracy of predicting positive biopsy results. MATERIALS AND METHODS: Results of prostate biopsy in 130 consecutive patients were correlated with transrectal ultrasound (TRUS) findings, digital rectal examination results, serum PSA level, and excess PSA (serum PSA level minus predicted PSA level [prostate volume x 0.12]), alone and in combination. Random sextant biopsy was performed in all patients, as well as directed biopsy of any suspicious lesion seen at TRUS. RESULTS: Excess PSA alone was most accurate in the prediction of positive biopsy results. Use of an excess PSA of > or = 0 ng/mL instead of a serum PSA level of > 4 ng/mL to initiate prostate biopsy increased the positive yield from 49% to 56% and accuracy from 51% to 62%, eliminating 21% of biopsies while maintaining sensitivity at 94% (vs 95% with serum PSA level). CONCLUSION: Use of only excess PSA of > or = 0 ng/mL to initiate prostate biopsy results in the best combination of sensitivity and specificity compared with the other standard parameters.

Aged↗
PubMed1995

Effect of a main renal artery stenosis on the downstream Doppler waveform in dogs.

RATIONALE AND OBJECTIVES: We evaluated the changes in the down-stream Doppler waveforms caused by a proximal stenosis in the main renal artery of dogs. METHODS: Renal parenchymal arterial waveforms downstream from mild (< 50%), moderate (50-75%), and severe (76-95%) stenoses were compared with nonstenotic baseline waveforms in five mongrel dogs. Waveform shapes were categorized as biphasic or monophasic. The percentage of biphasic and monophasic waveforms was determined for each stenosis. The acceleration index (AI) and the acceleration time (AT) were determined using traditional and modified calculations (AI' and AT'). Late systolic deceleration (DS), diastolic deceleration (DD), and the resistive index (RI) also were measured. RESULTS: AT, AI', and AT' demonstrated significant differences between the severe stenoses and nonstenotic baselines (p < .05); however, there was no difference between the mild and moderate stenoses versus baselines. The percentage distribution of monophasic and biphasic waveforms was highly correlated with the degree of stenosis. Monophasic waveforms increased on average from 22.5% of baseline waveforms to 76.5% of waveforms in the severe stenoses. Biphasic waveforms decreased on average from 69.9% of baseline waveforms to 18.7% of waveforms in the severe stenoses. CONCLUSION: Quantitative evaluation of the downstream waveform parameters (AI, AT, AI', AT', DS, DD, and RD in the dog kidney is not sufficiently accurate, but calculation of the percentage of the monophasic and biphasic waveforms present may be useful to predict a hemodynamically significant renal artery stenosis (> or = 50%).

Animals↗
PubMed1995

Diagnosis of renal artery stenosis in transplanted kidneys: value of Doppler waveform analysis of the intrarenal arteries.

OBJECTIVE: The objective of this study was to determine in renal transplant patients if the acceleration time and subjective assessment of dampening of the waveforms from the intrarenal arteries improves the accuracy of detecting a hemodynamically significant (> or = 50%) proximal arterial stenosis compared with measurements of peak systolic velocity from a main renal artery. MATERIALS AND METHODS: In 15 patients, the findings of 19 Doppler sonograms and corresponding arteriograms of their renal transplants were reviewed, with arteriography serving as the gold standard. Four patients had a significant proximal arterial stenosis; three were of the main renal artery and one was of the adjacent external iliac artery proximal to the anastomosis with the renal artery. RESULTS: We found a significant prolongation of the acceleration time in patients with a significant proximal arterial stenosis (p = .0004). Use of a threshold acceleration time of 0.10 sec or subjective assessment of dampening of the waveforms resulted in an accuracy of 95% in detecting a significant proximal arterial stenosis. This compared with an accuracy of 62% in detecting a significant proximal arterial stenosis using a peak systolic velocity threshold of 2.0 m/sec as the sole criterion. Using intrarenal arterial Doppler waveform parameters alone would have spared arteriography in 11 patients and would have detected three of four significant proximal arterial stenoses. CONCLUSION: In this study, Doppler waveform analysis of the intrarenal arteries improved the accuracy of screening for a significant proximal arterial stenosis. The results suggest that such analyses can be used to spare many patients with suspected renal vascular hypertension from unnecessary arteriography.

Adult↗
PubMed1990

Prenatal sonographic evaluation of short-limbed dwarfism: an algorithmic approach.

Prenatal sonographic evaluation of short-limbed dwarfism is initiated when a significantly shortened femur is found or by referral of a patient with a family history of skeletal dysplasia. If a short femur is demonstrated, all the long bones are measured and evaluated for bowing, fractures, and mineralization. The bone dysplasia is categorized according to whether it is mesomelic, rhizomelic, or micromelic and whether bowing or fractures are present. The fetal spine, head, thorax, hands, and feet are carefully evaluated to differentiate the type of bone dysplasia and to determine whether it is lethal. Serial examinations may be necessary. This approach will provide sufficient information to counsel the family, manage the pregnancy, and direct the postnatal evaluation.

Algorithms↗
PubMed1989

Duplex ultrasound evaluation of normal native kidneys and native kidneys with urinary tract obstruction.

The average resistive indices of 15 native kidneys from 8 patients with no known renal dysfunction were determined with the Doppler waveform obtained from the interlobar arteries. The average resistive index for this group was .58; the highest value was .66. The interlobar arteries of four native kidneys with urinary tract obstruction as well as those of the contralateral unobstructed kidneys were evaluated by Duplex ultrasound. Unilateral urinary tract obstruction was due to a congenital ureteropelvic junction obstruction in one patient or an acutely obstructing calculus at the ureterovesical junction in three patients. The average resistive index of the four obstructed kidneys was .75 and the lowest value was .71. The average resistive index of the four contralateral unobstructed kidneys in these patients and the 15 kidneys from patients with no known renal abnormalities was .58, which was significantly different from the value for the obstructed kidneys (p less than .005). The resistive index from the interlobar arteries of normal native kidneys is reproducible as previously reported in renal transplants. Pathologic renal processes, such as urinary tract obstruction, may be characterized by abnormally high resistive indices.

Adolescent↗
PubMed1988

Gastrostomy tube pancreatitis.

Acute pancreatitis developed in a child following inadvertent placement of a gastrostomy tube balloon in the descending duodenum. After a gastrostomy tube is inserted, radiologic confirmation of correct tube position is recommended to help avoid this rare iatrogenic complication.

Acute Disease↗
PubMed1988

The diaphragm: anatomic, pathologic, and radiologic considerations.

The diaphragm, by virtue of its complex anatomy and multiple ligamentous connections to both thoracic and abdominal structures, is more than a simple partition between the chest and abdomen. Cross sectional images of the diaphragm and peridiaphragmatic processes can be confusing unless the radiologist is aware of the normal structure of the diaphragm, its attachments to the body wall, and the multiple ligaments that attach to the diaphragm.

Adult↗
PubMedDate not supplied

Sonography: a useful tool to detect the mechanical causes of renal transplant dysfunction.

PURPOSE: The purpose of this study was to evaluate the utility of sonography in distinguishing between mechanical and nonmechanical causes for renal transplant dysfunction. METHODS: We reviewed all ultrasound examination reports (n = 286) for 63 consecutive patients who received 64 renal transplants. We assessed the sensitivity and specificity of different degrees of hydronephrosis (mild, moderate, or severe) in detecting urinary tract obstruction; different volumes of new or increasing peritransplant fluid in detecting urine leaks; different total volumes of peritransplant fluid in predicting significant compression of the transplant; and Doppler vascular criteria for predicting arterial and venous occlusion. RESULTS: All mechanical complications were detected (100% sensitivity) with specificities of 91.9% for ureteral obstruction (criterion, moderate hydronephrosis), 83.4% for urine leaks (criterion, any new fluid or any increase), 91.4% for fluid collections that compressed the transplant (criterion, > 100 ml), and 100% for vascular occlusion (criteria, no flow for arterial occlusion; no venous flow and reversal of arterial flow during diastole for venous occlusion). CONCLUSIONS: Sonography is very useful in distinguishing between mechanical and nonmechanical causes for renal transplant dysfunction. It has high sensitivity and acceptable specificity in this setting.

Adolescent↗
PubMedDate not supplied

Testicular epidermoid cysts: sonographic features with histopathologic correlation.

Testicular epidermoid cysts are rare, accounting for 1% of all testicular tumors. We present the sonographic appearances of epidermoid cysts in 3 cases, together with the histopathologic correlation. In case 1, sonography showed an intratesticular hypoechoic mass with a well-defined echogenic rim; the mass measured 1.8 x 1.5 x 1.5 cm, and there was no evidence of calcification. In case 2, sonography showed a well-circumscribed mass measuring 1.3 x 1.3 x 1.0 cm, with alternating hypoechoic and hyperechoic rings (onion-ring appearance) and no calcifications. In case 3, sonography showed a 2.4- x 2.3- x 2.3-cm, well-circumscribed, oval mass with a heterogeneous echotexture and an outer hypoechoic halo. The mass contained plaque-like regions of increased echogenicity, with peripheral acoustic shadowing from refraction artifact. Hypoechoic clefts were visualized posterior to the plaque-like areas. The triad of findings-sonographic appearance of an onion ring, avascularity on Doppler sonography, and negative results of tumor marker studies-is highly suggestive of an epidermoid cyst.

Adult↗
PubMedDate not supplied

Delayed computed tomographic characterization of renal masses: preliminary experience.

BACKGROUND: To evaluate the performance of delayed contrast enhanced computed tomography (DCT) in characterizing renal masses. METHODS: Twenty-four patients with suspected renal masses or indeterminate renal masses on previous imaging studies were prospectively evaluated with preintravenous contrast imaging, conventional contrast-enhanced computed tomography (imaging initiated 2 min after intravenous contrast injection), and DCT (imaging initiated 13 min after injection of intravenous contrast). Only lesions larger than 1.0 cm were evaluated, with scanning parameters kept constant across the three scans. RESULTS: All pathologically confirmed renal cell carcinomas (n = 6) were detected on DCT using a threshold attenuation decrease of 10 Hounsfield units (HU). A significant decrease (p = 0.031) in attenuation occurred in renal cell carcinomas (mean = 29.6 +/- 23.6 HU) compared with the attenuation change (mean decrease = 1.1 +/- 7.1 HU), which occurred in non-neoplastic renal cysts (n = 34). Non-neoplastic renal cysts were correctly classified by DCT 32 of 34 times (94%). CONCLUSIONS: In this study, DCT distinguished renal cell carcinomas from non-neoplastic cysts in a vast majority of cases and may aid in characterizing incidentally discovered renal lesions on postcontrast CT.

Adenoma↗
PubMedDate not supplied

Urine leaks in renal transplant patients. Diagnostic usefulness of sonography and renography.

We evaluated the utility of sonography and nuclear medicine renography in the detection of urine leaks in 57 renal transplant patients. Sonography and renography were equally sensitive in detecting leaks. But renography was more specific and therefore accurate (p < 0.0001) in detecting leaks. Urine leaks should be considered on sonography, which is often the first imaging study ordered in evaluating renal transplants, with new or increasing peritransplant fluid collections. Leaks should be confirmed by renography before performing additional invasive radiologic or surgical procedures.

Adolescent↗
PubMedDate not supplied

Doppler respiratory patterns in the femoral veins with pelvic vein obstruction.

An appropriate Doppler response to valsalva in the common femoral veins has been described previously as excluding a more proximal venous obstruction. We describe our experience in three patients in whom an appropriate response to valsalva did not exclude a more proximal pelvic venous obstruction. Dampening of the Doppler waveforms on the affected side when compared with the opposite limb led to the diagnosis of proximal venous obstruction.

Adult↗