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S A Lapin

Publications and source records attributed to S A Lapin.

11 recordsLinked to original sources
PubMed1987

Cholelithiasis: evaluation with CT.

Computed tomography (CT) is often the first imaging modality used in the diagnosis of patients with suspected abdominal disease. While it is known that early generation CT scanners often detect gallstones, the detection rate of newer equipment is not widely known. Abdominal CT scans of 226 patients who had undergone ultrasonographic (US) studies of the gallbladder were reviewed in a blinded study to determine the accuracy of state-of-the-art CT scanning equipment in the detection of cholelithiasis. Of 110 patients with US or surgical evidence of cholelithiasis, gallstones were demonstrated on CT images of 87 (79.1% sensitivity). Overall accuracy was 89.8%, while specificity was 100%. On CT images stones could appear densely (48.3%) or slightly (11.5%) calcified, as an area with a rim of increased density (21.8%), as an area of soft-tissue density (14.9%), or as an area of low density (3.4%). Stone size, stone density, section incrementation, and the pericholecystic anatomy affected the detection rate. Understanding the spectrum of findings and the other factors involved can optimize success of diagnosis of cholelithiasis on the basis of CT examinations.

Cholecystography↗
PubMed1986

Hepatobiliary imaging in choledocholithiasis. A comparison with ultrasound.

A retrospective analysis of preoperative biliary imaging and ultrasound in 22 patients with surgically proven choledocholithiasis was performed. Ultrasound detected dilated ducts greater than 7 mm in 11 of 14 jaundiced patients (79%). Hepatobiliary imaging was able to detect either absent or delayed bowel visualization or prominent bile ducts in 13 of 14 jaundiced patients (93%). Of eight nonjaundiced patients, ultrasound showed dilated ducts in three (38%). Hepatobiliary imaging showed either absent bowel activity or prominent ducts in six of eight nonjaundiced patients (75%). Twenty of 22 patients had stones in the gallbladder that were detected by ultrasound, although only one patient had actual visualization of the common duct stone. Hepatobiliary imaging may show abnormalities in choledocholithiasis with normal ultrasound studies.

Adult↗
PubMed1986

Pheochromocytoma: detection by unenhanced CT.

During a 2 1/2-year period, 10 patients with suspected pheochromocytoma were evaluated by unenhanced computed tomography (CT). Six adrenal masses, one hyperplastic adrenal gland, and two extraadrenal retroperitoneal masses were detected in seven patients; CT of the adrenals and retroperitoneum was normal in three patients. Scintigraphy with iodine-131 metaiodobenzylguanidine (131I-MIBG) was performed in nine of the 10 patients and corroborated the CT findings in all cases. In the three patients with normal CT and 131I-MIBG scintigraphic findings, follow-up assays of serum catecholamines were normal. In six of the seven patients with abnormal CT scans, surgical and pathologic confirmation was obtained; one patient was lost to follow-up after her CT scan. Unenhanced CT is recommended as the initial localizing procedure in patients with suspected pheochromocytoma, thereby avoiding the small but finite risk of hypertensive crisis associated with intravenous injection of urographic contrast medium.

Adrenal Gland Neoplasms↗
PubMed1985

Real-time sonography in suspected acute cholecystitis. Prospective evaluation of primary and secondary signs.

Sonographic findings in 497 patients with suspected acute cholecystitis were analyzed prospectively. Combined use of primary and secondary sonographic signs led to excellent positive and negative predictive values. Positive predictive values for stones combined with either a positive sonographic Murphy sign (92.2%) or with gallbladder wall thickening (95.2%) were excellent for acute cholecystitis. Positive predictive value of these signs for patients requiring cholecystectomy was even higher (99.0%). Negative predictive values for combined use of primary and secondary signs to exclude acute cholecystitis were also excellent (95.0% for no stones and negative sonographic Murphy sign). Real-time sonography alone, using both primary and secondary signs, can be definitive in nearly 80% of patients with suspected acute cholecystitis. These patients require no further imaging evaluation. Sonography should be the screening test of choice in acute cholecystitis because it is cost effective, prospectively highly accurate, quick, and better at characterizing and detecting other abdominal lesions than cholescintigraphy. A proposed algorithm is described.

Acute Disease↗
PubMed1984

The insensitivity of sonography in the detection of choledocholithiasis.

To determine the sensitivity of sonography in the detection of choledocholithiasis, the sonograms of 138 patients with surgically proven common bile duct stones were reviewed. A definite diagnosis of choledocholithiasis could be made on the basis of the sonograms in 22% of cases. Overall, 23% had common ducts of normal caliber (less than or equal to 7 mm diam) and 23% had normal total bilirubin levels at the time of the examination. Although a sonographic diagnosis of choledocholithiasis provides important information for the surgeon, the method is not sufficiently sensitive to serve as a definitive preoperative test for common bile duct stones.

Adult↗
PubMed1982

Prospective evaluation of the sonographic Murphy sign in suspected acute cholecystitis.

The sonographic Murphy sign, the presence of maximal tenderness elicited over a sonographically localized gallbladder, has been considered useful in the evaluation of patients with suspected acute cholecystitis. We prospectively evaluated this sign in 427 consecutive patients referred for evaluation of acute cholecystitis. The overall accuracy of the sonographic Murphy sign in the 219 patients with sufficient confirmation to be included in the statistical analysis was 87.2%. Sensitivity was 63% and specificity was 93.6%. The predictive value of a positive sign was 72.5%, while the predictive value of a negative sign was 90.5%. The sonographic Murphy sign is a useful, albeit imperfect, adjunct in the assessment of patients with suspected acute cholecystitis.

Acute Disease↗
PubMed1982

Sonography of pyogenic splenic abscess.

Pyogenic splenic abscess is an uncommon lesion associated with high mortality. Diagnosis may be difficult, especially in deep-seated abscesses. Plain radiographs and nuclear medicine techniques may be helpful, but can be insufficiently specific. Sonography, which images morphologic changes, is useful in assessing splenic abscesses. Five of six abscesses had a predominantly anechoic pattern with internal foci of higher echogenicity. In one gas-containing lesion, there were high amplitude echoes throughout the abscess. The abscesses were easily distinguishable from the surrounding homogeneous normal spleen. Sonography, while not definitive, is an effective tool in reaching an early diagnosis of splenic abscess. This allows prompt splenectomy, ameliorating prognosis.

Abscess↗
PubMed1979

Gray-scale ultrasonography of hepatic amoebic abscesses.

Retrospective analysis of the ultrasonograms of 42 hepatic amoebic abscesses in 34 patients was performed. All lesions were less echogenic than normal liver. All but 1 were contiguous with the liver capsule and had slight distal sonic enhancement. Twenty-three were predominantly homogeneous with fine, low-level echoes. This pattern is highly suggestive of hepatic amoebic abscess. Nineteen abscesses did not show this pattern and could not be diagnosed based on ultrasonographic criteria.

Humans↗
PubMedDate not supplied

Predicting the cause of common bile duct obstruction with sonographic data: analysis of binary variables.

A retrospective analysis of 71 patients with proven common bile duct obstruction, who had not undergone previous biliary surgery, was performed. To determine optimal criteria for differentiating stone from nonstone obstruction by ultrasonography, five sonographic signs were analyzed as binary variables. These signs are the demonstration of (1) common duct stones, (2) mass at the site of the common bile duct, (3) gallbladder stones, (4) gallbladder volume greater than a critical value, and (5) common duct diameter greater than a critical value. Maximum expected accuracy was 85% achieved by prediction based on a set of three variables: common duct stone, common duct mass, and gallbladder stones. This was not significantly better than the accuracy (82%) achieved by prediction on the basis of gallbladder stones alone. Three signs in combination, ie, demonstration of gallbladder stones, gallbladder volume less than 52 ml, and common duct diameter less than 14 mm, had predictive value equal to demonstration of a common duct stone as an indicator that common bile duct obstruction is the result of a stone.

Adolescent↗