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S G Silverman

Publications and source records attributed to S G Silverman.

At least 55 records · Page 3Linked to original sources
PubMed1995

Helical (spiral) CT of the retroperitoneum.

Helical CT promises to improve imaging of the retroperitoneum through the elimination of respiratory misregistration and the minimization of partial volume averaging. The speed of acquisition enables the entire abdomen and pelvis to be imaged in less than 2 minutes with standard collimator widths. This is a distinct advantage in critically ill patients, particularly in the case of trauma. Selective intravenously administered contrast enhancement is made possible with helical CT. Rapid scanning allows imaging in an arterial, renal cortical, renal medullary, or delayed collecting system phase. This property of helical CT enables CT angiography to emerge as a powerful minimally invasive alternative to conventional arteriography for imaging the abdominal aorta and its branches. After 4 years of investigating the use of volumetric CT, the clinical settings described herein remain the only clear indications for using helical CT in the kidney and retroperitoneum. These studies took advantage of the single most important feature of helical CT--the elimination of respiratory misregistration. Two broad diagnostic advantages result: (1) the ability to search and characterize a region thoroughly, such as in the evaluation of a small renal mass, or to search for the needle-tip during an interventional procedure; and (2) the ability to create multiplanar and 3-D images that are of sufficient quality to be useful in clinical practice, such as in imaging the vasculature (CT angiogram), and in surgical planning.

Adrenal Gland Diseases↗
PubMed1994

Retro-peritoneoscopy: anatomical rationale for direct retroperitoneal access.

Although the upper urinary tract resides at an extraperitoneal location, the traditional laparoscopic approach to these organs has been transperitoneal. Several investigators have advocated using a direct approach to the retroperitoneum to minimize risks associated with transperitoneal surgery. We performed autopsy and radiographic studies in an effort to define the location of the retroperitoneum relative to surface anatomy. These investigations indicate that the peritoneal reflection was consistently anterior to the posterior axillary line. Moreover, when a patient was placed in the lateral position, the anteroposterior extent of the potential retroperitoneal space increased 2-fold. Based on these studies, a technique for direct retro-peritoneoscopy was initiated and successfully performed in 21 of 23 patients. Direct access to the retroperitoneum can be performed in a reliable and safe manner.

Humans↗
PubMed1994

Three-dimensional imaging and display of renal tumors using spiral CT: a potential aid to partial nephrectomy.

OBJECTIVE: A new technique for creating three-dimensional (3D) images of renal tumors using contrast-enhanced spiral computed tomography (CT) is described and preliminarily investigated. METHODS: 3D spiral CT was employed in 2 patients before radical nephrectomy and in 5 patients before partial nephrectomy. Preoperative and postoperative image analyses were conducted to evaluate the ability of the images to depict key anatomic relationships in planning partial nephrectomies. RESULTS: 3D spiral CT defined the tumor's location and relationship to the kidney surface better than the tumor's proximity to renal hilar vessels and collecting system. Negative surgical margins were obtained in all 4 patients with renal cell carcinoma, and post-operative serum creatinine remained less than 2 mg/dL in all 5 patients after partial nephrectomy. CONCLUSIONS: This early experience suggests that 3D spiral CT can help in the planning of partial nephrectomy and in attaining complete resection of renal cell carcinoma while conserving normal renal tissue.

Adult↗
PubMed1994

Impact of positive findings at image-guided biopsy of lymphoma on patient care: evaluation of clinical history, needle size, and pathologic findings on biopsy performance.

PURPOSE: To analyze the effect of findings at image-guided biopsy of abdominal lymphoma (IGBL) on patient care and define the key determinants of clinical success. MATERIALS AND METHODS: A retrospective, bi-institutional study was performed in 102 patients with positive or suspicious IGBL findings (93 patients with non-Hodgkin and nine patients with Hodgkin lymphoma). The proportion of patients treated on the basis of IGBL findings only was calculated and correlated with 10 determinants, including history of lymphoma, biopsy technique, needle size, immunocytochemical findings, and tumor grade. RESULTS: Overall, 73 patients (72%) were treated on the basis of biopsy findings only, including 41 (91%) of 45 patients with a history of lymphoma and 32 (56%) of 57 patients with no such history (P < .01). No difference in findings existed when three needle-size groups were compared (P > .50). CONCLUSION: Whenever findings were positive, IGBL provided enough tissue to enable treatment in most patients. Fine needles were just as likely as larger needles to enable both determination of tumor grade and treatment.

Biopsy, Needle↗
PubMed1994

Medical impact of unedited preliminary radiology reports.

PURPOSE: To determine the potential frequency of adverse patient outcomes resulting from erroneous preliminary radiology reports. MATERIALS AND METHODS: The authors determined the number of preliminary radiology reports that changed substantively between the preliminary and final version during a 10-day collection period. They analyzed 200 of 1,648 reports to determine the potential for adverse outcome. RESULTS: Only 5.6% of the preliminary radiology reports were changed substantively. Two percent of all reports contained changes that would have led to additional testing or treatment and, possibly, increased morbidity. CONCLUSION: Immediate electronic transfer of a preliminary radiology report results in a small but important number of adverse outcomes; however, if a final edited report follows within 24 hours and referring physicians are called whenever the preliminary report contains erroneous information, the benefits of rapid information transmission may outweigh the additional risks.

Boston↗
PubMed1994

Design and implementation of a new radiology consultation service in a teaching hospital.

The steady increase in costs related to testing has been a major factor in the overall growth of health care expenses. Concern is substantial about the excessive number of tests ordered by physicians without measurable improvement in patients' outcomes. This is of particular concern in teaching hospitals, because in addition to the direct impact on national health care expenditures, these are the institutions in which young physicians train and formulate test-ordering practices. Proper selection of imaging tests is a complex process that requires detailed information about the patient; specific questions to be answered; and knowledge of the characteristics of the test, including sensitivity, specificity, risks, and cost. To date, no systematic method exists for combining the expertise of the radiologist with that of the referring physician before the tests are selected. Therefore, we designed a new clinical service within the radiology department that allows formal, on-the-ward consultation to assist internal medicine housestaff in the selection of radiologic tests. The goal of this study was to assess the feasibility of this formal radiology consultation service and to determine how often its imaging recommendations were implemented for patients with complicated medical conditions.

Boston↗
PubMed1994

Small (< or = 3 cm) renal masses: correlation of spiral CT features and pathologic findings.

OBJECTIVE: We describe our 3-year experience using spiral CT in the evaluation of small renal masses in order to determine the usefulness of this technique for classifying the lesions and to correlate specific CT features with pathologic findings. MATERIALS AND METHODS: We retrospectively analyzed spiral CT scans and results of pathologic examinations of surgically extirpated small (< or = 3 cm) renal masses in 35 patients. The masses included 27 renal cell carcinomas, two transitional cell carcinomas, one leiomyoma, one angiomyolipoma, and four benign cysts. Several imaging features, including attenuation, pattern of contrast enhancement, presence and type of calcification, cyst wall, and septation, were correlated with pathologic findings. RESULTS: Most renal cell carcinomas had a solid growth pattern (n = 19), had attenuation values on unenhanced scans of 20 H or greater (n = 26), and had attenuation values that increased by at least 10 H with contrast enhancement (n = 26). Only three renal cell carcinomas were mostly cystic on pathologic examination. Heterogeneous enhancement correlated with the presence of acellular regions (p = .02). Of 12 cystic masses, spiral CT showed the absence of a thick or nodular fibrous capsule in seven of nine masses (specificity, 0.78) and the absence of several (or nodular) septations in six of seven masses (specificity, 0.86) but was not as sensitive in detecting these features. CONCLUSION: Spiral CT can show many of the key imaging features of small renal masses used to distinguish between benign and malignant lesions. However, despite the theoretical benefits of volumetric CT, some lesions remain indeterminate and require surgical removal for diagnosis.

Carcinoma, Renal Cell↗
PubMed1993

Predictive value of image-guided adrenal biopsy: analysis of results of 101 biopsies.

A retrospective study of 97 patients undergoing 101 image-guided adrenal biopsies (IGABs) was performed to analyze the effects of specific pathologic results on test characteristics. Three categories of pathologic results (benign adrenal tissue, malignant tissue, and nondiagnostic) were compared with outcomes. Diagnostic samples were obtained in 86% of cases. Among 72 patients with proved outcomes, IGAB had an accuracy of 96%, a sensitivity of 93%, and a negative predictive value of 91% (92% in patients with bronchogenic carcinoma). In this subset of patients, 33 had biopsy specimens that contained benign adrenal tissue. In these 33 patients, three masses (each smaller than 3 cm) proved malignant. In the 14 patients with nondiagnostic samples, two masses proved malignant. Obtaining benign adrenal tissue was highly predictive of benignity, even in the setting of lung cancer. The authors conclude that IGAB is an accurate procedure in both oncologic and nononcologic patients. However, when the biopsy specimen does not contain benign adrenal tissue or malignant cells, repeat percutaneous biopsy or surgery should be considered.

Adrenal Gland Diseases↗
PubMed1993

Prospective comparison of T2-weighted fast spin-echo, with and without fat suppression, and conventional spin-echo pulse sequences in the upper abdomen.

PURPOSE: To evaluate use of fast spin-echo (FSE) magnetic resonance imaging with and without fat suppression in the liver and upper abdomen. MATERIALS AND METHODS: Conventional spin-echo (SE) T2-weighted, FSE T2-weighted, and fat-suppressed FSE T2-weighted images from 37 patients strongly suspected to have focal hepatic lesions were evaluated. RESULTS: Quantitative analysis demonstrated that fat-suppressed FSE imaging had the highest lesion-liver contrast-to-noise ratio; conventional SE imaging, the lowest. In a qualitative analysis, FSE imaging was preferred. In a rank order analysis, FSE imaging was preferred 83% of the time and fat-suppressed FSE imaging 17% of the time as regards overall image quality; fat-suppressed FSE imaging was preferred 64% of the time, FSE imaging 23% of the time, and conventional SE imaging 13% of the time as regards signal abnormality detection. CONCLUSION: FSE imaging with and without fat suppression is a potentially useful pulse sequence for evaluating the upper abdomen.

Abdomen↗
PubMed1992

Needle-tip localization during CT-guided abdominal biopsy: comparison of conventional and spiral CT.

OBJECTIVE: This study was performed to determine whether the time required for needle-tip localization during biopsy of the abdomen would be reduced if continuous-volume data acquisition, also known as spiral CT, were used for guidance instead of conventional CT. SUBJECTS AND METHODS: Forty patients had biopsies of an abdominal mass; half underwent needle-tip localizations with conventional CT and half with spiral CT. The times required to localize the needle for 104 needle passes were calculated; scanning and reconstruction times were included, and the radiologist's technique and procedural difficulties were deliberately excluded. The mean needle localization times with conventional and spiral CT were compared for the upper abdominal and pelvic regions by using the two-tailed unpaired Student's t-test. RESULTS: The mean time (+/- SE) for spiral CT was 35 +/- 2 sec compared with 105 +/- 18 sec for conventional CT (p < .001). When analyzed by region, times with spiral CT were shorter in both the upper abdomen (means, 37 sec for spiral CT vs 150 sec for conventional CT, p < .001) and pelvis (means, 25 sec for spiral CT vs 74 sec for conventional CT, p = .038); the magnitude of the improvement was greater in the upper abdomen. CONCLUSION: The time required to find the needle tip during guided biopsy of an abdominal mass is reduced with spiral CT compared with conventional CT. This improvement is partly a result of the ability to eliminate respiratory misregistration with spiral CT, which is not possible with conventional multisectional CT; hence the greater advantage in upper abdominal biopsy.

Abdominal Neoplasms↗
PubMed1991

Current use of screening laboratory tests before abdominal interventions: a survey of 603 radiologists.

A survey of 2,153 radiologists was conducted to assess both their current practices of evaluating hemostatic function and their use of blood tests before performing image-guided nonvascular abdominal interventions. Among the 603 (28%) who responded, more radiologists routinely perform prothrombin time (81%) or partial thromboplastin time (78%) tests than platelet counts (59%), and relatively few (7%) obtain bleeding times. The most common practice (51%) is to order all of the first three tests. Use of laboratory tests is quite common (greater than 75%) before biopsy of splenic masses, hemangiomas, or hepatomas and before all catheter insertions. These tests are used less frequently (less than or equal to 70%) before fine-needle procedures, including biopsy and cyst aspiration. Only one-third of the radiologists alter their evaluation in patients who have taken aspirin. Most respondents (64%) believe that there should be written guidelines on how to evaluate patients before interventional procedures. Virtually all (97%) thought such evaluation should be the radiologist's responsibility.

Aspirin↗
PubMed1991

The penis.

Explore the source record for details and available documents.

Diagnostic Imaging↗
PubMed1990

Percutaneous gastrostomy with gastropexy: experience in 125 patients.

We report our experience with radiologically guided percutaneous tube gastrostomy in 125 patients by using a gastropexy technique in which the anterior gastric wall is nonsurgically sutured to the anterior abdominal wall with percutaneously placed T-fasteners before catheter insertion. Short-term follow-up of up to 2 weeks was available in all patients. In 63 patients, long-term follow-up (greater than 4 weeks; average, 3.5 months; maximum, 1 year) was available. Catheter placement was successful in 124 (99%) of 125 patients, including three patients with anatomic changes after Bilroth II hemigastrectomy and two patients with failed endoscopic attempts. There were no deaths related to the procedure, and no patients required surgical intervention for complications attributable to the gastrostomy procedure. The 30-day mortality rate was 11% (n = 7). These deaths were due to cardiorespiratory arrest and were not attributable to the gastrostomy procedure. Major complications occurred in 1.6% (n = 1) and minor complications in 9.5% (n = 6). These results indicate that percutaneous gastrostomy with gastropexy is a safe and effective technique for placement of catheters in the stomach.

Adult↗
PubMed1989

Drainage of a malignant common hepatic duct obstruction by a biliary endoprosthesis placed through a T-tube tract: technical note.

For patients with high biliary obstruction drained by a T-tube, achieving internal drainage requires special techniques. Modification of a method described by Sammon for common bile duct obstruction permits placement of a biliary endoprosthesis astride the T-tube tract. The key step is traction exerted downward on the endoprosthesis by a suture passing through a second catheter temporarily inserted into the common bile duct. A case is described in which the technique has been applied successfully.

Adenocarcinoma↗
PubMed1989

Migratory lobar nephronia.

Lobar nephronia or focal bacterial nephritis is a pre-abscess stage of localized cellulitis and has been shown to represent a focal imaging manifestation of what is frequently a diffuse renal process. To the best of our knowledge, although multi-focal bacterial nephritis has been described, a migratory pattern has not been observed. This report describes a previously healthy 32-year-old woman with pathologically proven lobar nephronia that exhibited a migratory pattern on serial computed tomography (CT) and a prolonged course on antibiotic therapy. Possible etiologies for this unusual course, along with the CT, sonographic and needle biopsy features of this disease are discussed.

Adult↗