Biomedical subjects

S G Silverman

Publications and source records attributed to S G Silverman.

77 records · Page 5Linked to original sources

PubMedDate not supplied

MR appearance and spectral features of injected ethanol in the liver: implication for fast MR-guided percutaneous ethanol injection therapy.

PURPOSE: Our goal was to evaluate several fast MR strategies for monitoring ethanol distributions so that percutaneous ethanol injection might be guided with MRI. METHOD: Fast RF spoiled GRE sequences (SPGR) and T2-weighted rapid acquisition with relaxation enhancement (RARE) sequences with and without spectroscopic-quality water suppression techniques were assessed for their ability to depict the distribution of injected ethanol in ex vivo pig liver. A line scan Carr-Purcell-Meiboom-Gill spectroscopic imaging sequence was used to validate observations and measure spectral relaxation characteristics of the ethanol signal in liver. Injected deuterated ethanol was also tested as an alternative possibility to depict the distribution of ethanol. RESULTS: The water-suppressed T2-weighted RARE sequence depicted the distribution of ethanol better than other sequences. Deuterated ethanol appeared as a signal void on all sequences. CONCLUSION: Water-suppressed T2-weighted RARE sequences could be useful to rapidly monitor MR-guided PEI.

Animals↗

PubMedDate not supplied

Spiral CT in the evaluation of flank pain: overall accuracy and feature analysis.

PURPOSE: Our goal was to assess test reliability and identify those features that have the strongest positive and negative predictive values in the diagnosis of renal colic using spiral CT. METHOD: Fifty non-contrast-enhanced CT scans (5 mm slice thickness) obtained in patients presenting with flank pain were reviewed by three radiologists blinded to the final diagnoses. The sensitivity, specificity, and positive and negative predictive values for nine pertinent findings were determined as compared to clinical follow-up. RESULTS: Twenty-nine cases had findings of ureteral obstruction. Findings with the strongest positive predictive values (> 0.90) were ureteral stone, hydronephrosis, hydroureter, periureteral stranding, and ureterovesical junction edema. Findings with the strongest negative predictive values (> 0.89) were absence of hydronephrosis and hydroureter. The areas under the receiver operating curves for Readers 1, 2, and 3 were 0.970 +/- 0.030, 0.942 +/- 0.036, and 0.982 +/- 0.020. CONCLUSION: Absence of hydroureter and hydronephrosis on spiral CT images should prompt a search for a diagnosis other than an obstructing ureteral stone.

Adult↗

PubMedDate not supplied

CT and ultrasound features of metanephric adenoma in adults with pathologic correlation.

PURPOSE: The purpose of this work was to correlate the CT, ultrasound, and pathologic features of metanephric adenoma, a rare benign renal tumor in adults. METHOD: Retrospective review of medical records (1990-1997) revealed three adult female patients who had both preoperative imaging and nephrectomy with pathologic diagnosis of metanephric adenoma performed at our institution. CT (n = 3) and ultrasound (n = 2) features were reviewed in consensus by two radiologists and correlated with pathologic findings. RESULTS: In all three cases, the metanephric adenoma was of increased attenuation relative to adjacent renal parenchyma on unenhanced CT scans. No septa or calcifications were seen. Ultrasound images showed both tumors to be hyperechoic with enhanced through-transmission. CONCLUSION: The CT and ultrasound findings correlate with the pathologic features of a high nuclear-to-cytoplasmic ratio and psammomatous calcifications. In the adult population, it is unlikely that metanephric adenoma can be prospectively differentiated from renal cell carcinoma based on imaging features.

Adenoma↗

PubMedDate not supplied

Fine needle aspiration biopsy of idiopathic retroperitoneal fibrosis.

OBJECTIVE: To report three cases of idiopathic retroperitoneal fibrosis (IRF) diagnosed by fine needle aspiration (FNA) biopsy and confirmed by histologic examination. To our knowledge, this is the first report on the FNA findings in IRF. STUDY DESIGN: Specimens were obtained under computed tomographic guidance using the standard technique. Half the smears were ethanol fixed and stained with Papanicolaou stain, and the other half were air dried and stained with Diff-Quik. A cell block was prepared in all cases. RESULTS: Similar findings were seen in all three cases. The predominant elements were fibrous tissue and inflammatory cells, which occasionally occurred together but often were separate. The inflammatory cells were predominantly small lymphocytes, with occasional plasma cells, histiocytes and neutrophils. Smears from one case showed the inflammatory component only, but the cell block in all three cases showed both elements. The diagnosis of IRF was suggested in two of the three cases. All patients underwent laparotomy for diagnostic confirmation, and two had therapeutic resection of the lesion. Histologic material reflected the FNA findings, showing hyalinized fibrous tissue and an inflammatory cell infiltrate consisting of lymphocytes, plasma cells, histiocytes and neutrophils. No infection, arteritis or malignancy was present. CONCLUSION: Although the FNA picture is nonspecific, in combination with clinical and radiologic findings it is highly suggestive of a diagnosis of IRF. A presumptive diagnosis allows a rational approach to further evaluation and therapy, which, in most cases, is an exploratory laparotomy with ureterolysis.

Aged↗

PubMedDate not supplied

State-of-the-art imaging of acute pancreatitis.

The purpose of this essay is to focus on the characteristic imaging features, as revealed by a variety of radiological modalities, which allow for an accurate diagnosis and staging of acute pancreatitis. In addition, emphasis will be made on the role of imaging in providing early prognostic information about the outcome of the disease.

Acute Disease↗