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P D Radecki

Publications and source records attributed to P D Radecki.

51 records · Page 3Linked to original sources
PubMed1986

Scar sign of renal oncocytoma: magnetic resonance imaging appearance and lack of specificity.

This case report illustrates the magnetic resonance imaging (MRI) appearance of a typically asymptomatic renal oncocytoma as a homogeneous mass of medium signal with a stellate central region of decreased signal, representing the central scar. The MRI was correlated with computed tomography (CT), ultrasound (US), and gross pathologic appearance. The appearance of a central scar is not specific for oncocytoma and does not exclude renal cell carcinoma, as illustrated by a second case.

Adenoma↗
PubMed1986

Impact of magnetic resonance on staging of renal carcinoma.

Computerized tomography (CT), ultrasound, and angiography have been used for staging renal cell carcinoma. CT has proven to be the most reliable and sensitive of these techniques. Magnetic resonance (MR) has emerged recently as a viable alternative imaging modality. Five patients with renal cell carcinoma and suspected caval involvement were evaluated by CT, ultrasound, and MR. Caval extension and the differentiation of intra-versus retrocaval tumor was seen with greater clarity on MR scans; perinephric extension was seen equally well with both modalities. The primary tumor itself was better defined with CT. In patients with equivocal findings regarding the renal veins or inferior vena cava, MR is a valuable adjunct in preoperative evaluation. In patients at high risk for contrast administration, MR is the staging modality of choice.

Adult↗
PubMed1986

Magnetic resonance imaging diagnosis of Budd-Chiari syndrome.

Noninvasive imaging modalities may suggest the diagnosis of Budd-Chiari syndrome but they are rarely diagnostic. Inferior vena cavography, hepatic venography, and liver biopsy, alone or in combination, are usually necessary for definitive diagnosis. Because of its excellent depiction of blood vessels as regions of absent signal, magnetic resonance imaging has the potential to make a noninvasive diagnosis of hepatic vein thrombosis. A case illustrating the usefulness of magnetic resonance imaging in the diagnosis of Budd-Chiari syndrome is presented.

Adult↗
PubMed1986

Contrast medium precipitation during abdominal CT.

Abdominal computed tomography (CT) scans of 55 patients who had ingested Gastrografin (meglumine diatrizoate and diatrizoate sodium) diluted to 2% with tap water and flavored with a commercial fruit juice base were reviewed. Twenty patients (36%) demonstrated intraluminal precipitation of Gastrografin shown by focal areas of markedly increased attenuation within the gastric lumen or trapped within gastric folds. Beam-hardening artifact produced by precipitation was observed, which limited the diagnostic value of some examinations. In vitro CT scans of the same Gastrografin solution titrated with hydrochloric acid or sodium hydroxide showed that by raising the pH of the solution, precipitation was virtually eliminated. Fifty-one CT scans of the abdomen using a buffered Gastrografin solution demonstrated precipitation in only five patients. Properly buffered dilute oral Gastrografin solutions should significantly decrease the prevalence of precipitation during abdominal CT examinations.

Beverages↗
PubMed1986

Thorotrast-induced hepatosplenic neoplasia: CT identification.

Despite discontinuation of its use in the 1950s, the consequences of Thorotrast usage continue to be recognized. In a review of plain film and CT findings of 20 cases of Thorotrast exposure, 15 of 17 patients demonstrated Thorotrast accumulation in the liver and spleen on plain films. Typically, this appeared as regions of trabeculated increased density within the liver. The spleen was of normal or decreased size and often demonstrated a finely punctate pattern of opacification. Only two malignancies could be suggested on plain film alone: one hepatic and one splenic. Five patients with hepatic malignancies underwent CT examinations: three with cholangiocarcinoma, one with angiosarcoma, and one with hepatocellular carcinoma. No specific criteria could be established to distinguish among these lesions, as each neoplasm appeared as relatively low-density mass(es). Two cases of splenic angiosarcoma appeared as low-density filling defect(s) in the otherwise opaque spleen, one case primary and the other metastatic from the liver. CT was superior to plain radiography in detecting and characterizing Thorotrast distribution and any superimposed malignancy. In addition to periodic liver function tests, screening CT of patients exposed to Thorotrast might detect hepatic neoplasms at an operable stage.

Adenoma, Bile Duct↗
PubMed1986

MRI of hemorrhagic renal cysts in polycystic kidney disease.

Nine patients with polycystic kidney disease were examined by MRI, CT, and sonography. MRI distinguished among simple cysts, cysts complicated by prior hemorrhage, and coexistent renal cell carcinoma. On T1-weighted spin-echo images, simple renal cysts appeared as round, homogeneous, low-signal regions with smooth outer margins and a distinct interface with remaining normal renal parenchyma or adjacent cysts. Hemorrhagic cysts were seen as homogeneous medium- to high-signal intensity regions, and about half of them correlated with hyperdense cysts by CT. In five cases, fluid-iron levels were evident by dependent high-intensity layering within the cysts. Renal cell carcinomas occasionally show high intensity because of hemorrhage, but intratumoral fluid-iron levels have not yet been described. These results suggest that MRI is useful in differentiating between simple cysts, hemorrhagic cysts, and neoplasms when CT and sonography are indeterminate.

Adult↗
PubMed1986

The retrolenticular afterglow: an echo enhancement artifact.

A mathematical model for a sonogram containing a circular object with a sonic speed less than that of its surroundings was constructed. The circular object acts as a lens to the ultrasound beam, which explains the refractive artifacts often observed. An unexpected artifact is also predicted, a region of increased echogenicity, which the authors named the retrolenticular afterglow, since it occurs behind a lens-like structure. An experiment was designed to show the appearance of this artifact occurring distal to an ethyl alcohol-filled cylindrical well in a tissue equivalent phantom.

Gallbladder↗
PubMed1985

Magnetic resonance imaging of papillary renal cell carcinoma.

The authors report magnetic resonance (MR) studies in a case of papillary renal cell carcinoma. The preoperative ultrasound and computed tomographic scans suggested either a hemorrhagic cyst or a carcinoma, but the angiogram demonstrated avascularity. The magnetic resonance scan was more consistent with carcinoma than complicated cyst. We report the MR findings with pathologic correlation.

Carcinoma, Papillary↗
PubMed1984

Thyroid imaging: comparison of high-resolution real-time ultrasound and computed tomography.

High-resolution real-time ultrasound (US) and computed tomography (CT) were compared in 48 patients with a clinical diagnosis of thyroid abnormality and also correlated with biopsy or surgery. The modalities were considered comparable in 38 cases (79%), while CT was superior in 5 and US in 5. CT illustrated substernal extension of a goiter, demonstrated a 5-mm nodule not seen in US, showed 2 cases of thyroiditis better than US, and diagnosed a suspected thyroid mass as a lipoma anterior to the thyroid. US detected 4 nodules not seen on CT and resolved contiguous nodules that appeared to be a single nodule on CT. Both techniques lacked histopathological specificity. CT appears to be advantageous in detecting substernal thyroid extension and confirming thyroiditis, while the ability of US to detect small nodules makes it the procedure of choice in evaluating suspected intrinsic thyroid abnormalities.

Adolescent↗