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R L Smathers

Publications and source records attributed to R L Smathers.

10 recordsLinked to original sources
PubMed1990

Internal mammary lymphadenopathy: imaging of a vital lymphatic pathway in breast cancer.

The prognostic significance of metastases to the internal mammary lymph nodes in patients with breast carcinoma has long been recognized. While ipsilateral dissection of axillary nodes remains a popular staging strategy for breast cancer, surgical sampling of the upper anterior intercostal spaces, a tedious procedure, has been largely abandoned. Diagnostic imaging of the parasternal lymphatic pathway is a useful and noninvasive alternative to surgical staging. This report reviews the pertinent regional anatomy and illustrates the criteria for diagnosing internal mammary lymphadenopathy by means of lateral chest radiography, computed tomography, high-resolution sonography, magnetic resonance imaging, and radionuclide lymphoscintigraphy.

Breast↗
PubMed1987

Testes and scrotum: MR imaging at 1.5 T.

Magnetic resonance (MR) images of the scrotum were obtained at 1.5 T in 20 subjects, 13 patients with intrascrotal pathologic conditions and seven healthy subjects. Characteristic MR imaging signals obtained on T1- and T2-weighted images allowed differentiation of testis from epididymis and spermatic cord. Masses were differentiated from normal testicular parenchyma in all cases. Atrophic or ischemic testes had lower signal intensity than normal testes on T2-weighted images. Hematoma displayed a characteristic high intensity on both T1- and T2-weighted images. Intratesticular and extratesticular pathologic conditions were readily differentiated. These results suggest that MR imaging is useful in the diagnosis of scrotal and testicular abnormalities.

Genital Diseases, Male↗
PubMed1986

Mammographic microcalcifications: detection with xerography, screen-film, and digitized film display.

Pulverized bone specks and aluminum oxide specks were measured by hand into sizes ranging from 0.2 mm to 1.0 mm and then arranged in clusters. These clusters were superimposed on a human breast tissue phantom, and xeromammograms and screen-film mammograms of the clusters were made. The screen-film mammograms were digitized using a high-resolution laser scanner and then displayed on cathode ray tube (CRT) monitors. Six radiologists independently counted the microcalcifications on the xeromammograms, the screen-film mammograms, and the digitized-film mammograms. The xeromammograms were examined with a magnifying glass; the screen-film images were examined with a magnifying glass and by hot light; and the digitized-film images were examined by electronic magnification and image processing. The bone speck size that corresponded to a mean 50% detectability level for each technique was as follows: xeromammography, 0.550 mm; digitized film, 0.573 mm; and screen-film, 0.661 mm. We postulate that electronic magnification and image processing with edge enhancement can improve the capability of screen-film mammography to enhance the detection of microcalcifications.

Breast Diseases↗
PubMed1986

[3-dimensional craniofacial computerized tomography].

Computed tomography allows today to reconstruct three-dimensional (3D) images from axial scans. The authors report their experience in cranio-facial pathology achieved in two Departments of Radiology (University of Trieste, Italy and University of Stanford, California). 3D images have been realized using two different softwares, one of which allows to reconstruct both soft tissue and bone structures. The applications in maxillo-facial traumas, cranio-facial malformations and head tumours are discussed. 3D images turned out to be very useful for the optimal visualization and for the spatial demonstration of the lesion and have potential applications in cranio-facial surgery and radiotherapy.

Facial Bones↗
PubMed1985

Intravenous cholangiography in the CT era.

With the availability of computed tomography (CT), ultrasonography (US), percutaneous transhepatic cholangiography (PTC), and endoscopic retrograde cholangiopancreatography (ERCP), the use of intravenous cholangiography (IVC) has waned. A retrospective study of 69 intravenous cholangiograms performed from 1979 through 1982 assessed the utility of intravenous cholangiography, as well as its effect on patient management, at an institution where CT was highly developed. In no case after normal findings on CT and/or ultrasound examination did IVC make a positive pathologic diagnosis. After abnormal results on CT and/or US examinations, in no case did IVC add to the diagnosis. Finally, after technically suboptimal results of CT and/or US examinations, IVC made only 1 positive pathologic diagnosis. Overall, IVC correctly demonstrated only 5 of 9 cases of common duct stones or strictures. Of the 26 cases with anatomical correlation there were a total of 7 false-positive and -negative IVC examinations. In this series, IVC was rarely useful in the diagnosis of biliary tract disease. Given the high inaccuracy rate of IVC in this study, its use for the exclusion of biliary tract disease is discouraged.

Biliary Tract Diseases↗
PubMed1985

Intratesticular adrenal rests diagnosed by ultrasound.

Adrenal rest tumors of the testes may occur in conditions associated with increased circulating adrenocorticotropic hormone (ACTH), including congenital adrenal hyperplasia (CAH) and Addison disease. Sonographically, these tumors appear as multiple round, hypoechoic nodules near the testicular hilus and are usually bilateral. They may undergo extensive fibrosis and become hyperechoic with acoustic shadowing. In the absence of excess ACTH or characteristic ultrasound findings, biopsy is recommended to exclude malignancy. Because malignant degeneration is very rare, close clinical and sonographic follow-up without biopsy is generally sufficient. Serial sonograms are useful to document stability or regression of tumor size during glucocorticoid replacement therapy.

Adrenal Rest Tumor↗
PubMed1985

Digital processing of film radiographs.

Initial clinical experience with a system for the digitization, processing, and display of film radiographs is described. Film is digitized using a high-intensity laser scanner; the recorded image data may then be subjected to a wide variety of processing options, with display of processed images on television monitors. The possibilities of clinical applications to processing and display of chest radiographs and film mammograms are described. A comparison of conventional analog subtraction and digitized film subtraction angiography indicated equivalent diagnostic capability, with the advantage of flexible, interactive image processing with the digital technique. A specially designed, energy-selective cassette permits dual-energy imaging from two films effectively exposed to different x-ray energy spectra. Dual-energy imaging may be capable of the characterization of body materials, including lung nodules, and useful for eliminating obscuring radiographic shadows overlying regions of interest.

Angiography↗
PubMed1985

[Digital radiology. Clinical experience].

The authors report the experience achieved at the Stanford University (USA) with a digital radiography system which allows the digitization of the film and of the images collected with photostimulable phosphors. The phosphor is essentially an intensifying screen where a latent image is stored after exposure to X-rays and is extracted by a laser scanning. The images collected with the digitized film and with the phosphor (chest, breast, bone) have been analyzed. The digitized film offers potential diagnostic advantages over the conventional film, because of the contrast manipulation and many other processing options. The possibility to recover the information of overexposed films appears very attractive. The photostimulable phosphors allow to get good quality images, with a consistent reduction of dose and costs. These plates offer the possibility, in the next future, to replace the conventional screen-film systems.

Female↗
PubMedDate not supplied

Computed tomography of amiodarone pulmonary toxicity.

Amiodarone, an antiarrhythmic agent, is known to induce pulmonary toxicity in some patients. Previously described radiographic findings include alveolar and interstitial infiltrates. We report a patient who developed biapical infiltrates on chest X-ray film and demonstrated an unusual, symmetric appearance on CT. Correlative postmortem histologic findings are presented. Amiodarone-induced pulmonary toxicity should be considered in the differential diagnosis of pulmonary parenchymal infiltrates seen on CT of patients receiving this medication.

Amiodarone↗