Search PubMed⌕ Search

Biomedical subjects

A A Moss

Publications and source records attributed to A A Moss.

At least 73 records · Page 4Linked to original sources

Uriniferous pseudocyst: computed tomographic findings.

The computed tomographic (CT) scans of nine consecutive patients with proved uriniferous pseudocyst (UP) were analyzed retrospectively. Analysis disclosed perirenal space tumefaction in seven patients, tumefaction outside the perirenal space in two patients, cystlike uniformity of attenuation (with specific exceptions) in all nine patients, contrast medium-opacified urine extravasating into the UP in three patients, contrast material within the dependent portion of the UP in one patient, anterior and superior displacement of the kidney in seven patients, hydronephrosis in all nine patients, and associated findings suggesting the underlying cause of UP in five patients. Although these CT findings appear to be quite specific, consideration of this uncommon entity in the CT differential diagnosis requires knowledge of its reported causes, the patient's medical history, and the clinical presentation.

Aged↗

Pleuropancreatic fistula: endoscopic retrograde cholangiopancreatography and computed tomography.

The complementary use of endoscopic retrograde cholangiopancreatography and computed tomography in the diagnosis and management of pleuropancreatic fistulas is described in relation to four cases in which computed tomography revealed the thoracic extension of a pancreatic fistula not demonstrable by endoscopic retrograde cholangiopancreatography, although the latter indicated an abnormal pancreatic duct. The complementary use of both techniques may be necessary to define the pathologic anatomy so that the appropriate therapy, particularly the surgical approach, can be decided.

Adult↗

Magnetic resonance imaging of the thyroid, thymus, and parathyroid glands.

Magnetic resonance (MR) images of the neck were obtained in 16 patients with use of a variety of spin echo and inversion recovery pulse sequences. Anatomic resolution was best with high-resolution spin echo images obtained with the pulse sequence repetition rate equal to 2.0 seconds and the echo delay equal to 28 msec because this imaging technique offered excellent contrast between normal tissues and had the highest signal noise ratio. The spatial resolution of MR was nearly as good as state of the art computerized tomography (CT). However, streak artifacts caused by motion and x-ray beam hardening often limited CT but did not affect MR. Tumors and lymph nodes were more easily differentiated from muscle and blood vessels with MR than with CT because of the superior soft-tissue contrast of MR. Tissue characterization allowed MR differentiation of thyroid nodules, thyroid cysts, and parathyroid tumors from normal thyroid tissue. Thyroid cyst fluid had the greatest water content and longest T1 and T2 relaxation times of all tissues studied. However, nonspecifically increased T1 and T2 relaxation times overlapped for a variety of neoplastic and inflammatory conditions. With further experience, MR imaging is likely to become a useful technique for the evaluation of neck masses.

Adenoma↗

How accurate are computed tomographic scans in assessment of changes in tumor size?

The computed tomographic scan plays an integral part in the diagnosis and management of tumors; however, its potential has not yet been fully exploited. With a computer-assisted volume determination method, the reproducibility of derived volume calculations was assessed, and radiologists' standard interpretations of interval change on serial scans were compared with the investigators' calculations of tumor volume change. Interobserver reproducibility of tumor volume calculations of the mean of two repeated volume determinations was satisfactory (mean of 3 percent, median of 1 percent). There were 29 comparisons (47 scans of 19 patients with liver tumors) of computed tumor changes with the radiologists' computed tomographic reports of consecutive scans. In only 41 percent (12 of 29) of the cases did the radiologists' interpretations and the computer-assisted volume determinations agree. It is concluded that objective computer-assisted volume determination provides a potentially more sensitive assessment of tumor change and that such precise, specific, reproducible determination of tumor volume should further clinical research and improve patient care.

Adult↗

Clinical nuclear magnetic resonance imaging of the body.

NMR promises great advances in diagnosis and has delivered so much already that it is expected that in the future it will replace many applications of the currently used imaging modalities. Although x-ray computed tomography is continuing to advance in speed of scanning and resolving power, NMR will most likely soon eliminate its use in many studies of the central nervous system and also in many other areas of the body. The promise of combining topical spectroscopy with imaging is also exciting and should provide further information about metabolic processes of various organs. Progress in NMR is so rapid and the future is so bright that one of the great problems will be to develop a new breed of radiologists who are versatile in biochemistry, mathematics, and computers, as well as competent in morphologic anatomy and pathologic physiology. As time goes on, advances in NMR will be achieved only by teams of clinical and basic scientists encompassing multiple disciplines.

Aortic Aneurysm↗

CT demonstration and guided aspiration of unusual adrenal metastases.

Certain malignant neoplasms commonly metastasize to the adrenal glands, whereas others do so only infrequently. In the latter circumstance, an adrenal mass is likely to be benign. We report 3 patients with malignant neoplasms (hepatoma, transitional cell carcinoma of the bladder, and squamous cell carcinoma of the vulva) that do not commonly metastasize to the adrenals in whom computed tomographic (CT) demonstration and guided aspiration of adrenal masses significantly affected patient management. CT guided aspiration of adrenal masses is safe and accurate and is recommended whenever a diagnosis of adrenal metastasis would alter the staging or therapy of the primary neoplasm.

Adrenal Gland Neoplasms↗

Malignant histiocytosis in a patient with sickle cell anemia: CT findings.

Malignant histiocytosis is a rare systemic disorder, characterized by progressive, invasive proliferation of atypical histiocytes. It is synonymous with the disease entity "histiocytic medullary reticulosis" initially described by Scott and Robb-Smith (Lancet 1939;194-8). To date, there have been slightly more than 100 cases reported in the literature. Although the radiographic features of malignant histiocytosis have been reported, to our knowledge there has not been any computed tomography (CT) description of the findings of this disease entity. The purpose of this report is to describe the serial CT findings of an unusual case of malignant histiocytosis in a patient with sickle cell anemia, presenting with weight loss and hepatosplenomegaly.

Adolescent↗

Value of computed tomography in interstitial 125I brachytherapy of prostatic carcinoma.

Computed tomography (CT) was performed in 20 patients with localized prostatic carcinoma before and after interstitial implantation of 125I seeds. Scans were analyzed to determine prostate volume, seed location, tumor response, and periprostatic tumor spread. CT volumes were an average of 25-30% greater than clinical estimates. In addition, CT demonstrated errors in implantation, including inhomogeneous distribution and extraprostatic seeds, in 17 patients (85%). Serial post-implantation scans showed no change in prostate volume in 12 patients (60%), a decrease in 7 (35%), and an increase in 1 (5%), concurring with clinical assessment of response to therapy. In 2 patients, clinically unsuspected tumor spread was identified on the CT scan.

Aged↗

Nuclear magnetic resonance imaging of the adrenal gland: a preliminary report.

Nuclear magnetic resonance (NMR) imaging characteristics of the normal and abnormal adrenal gland were evaluated and compared with findings on computed tomography (CT). Forty-two patients were examined: 36 had normal adrenal glands and 6 had adrenal disease (3 metastatic lesions, 1 pheochromocytoma, and 2 cortical hyperplasia). NMR clearly showed all 42 left adrenals (100%) and 36 right adrenals (86%). In some patients, it appeared to differentiate the adrenal cortex from the medulla. The ability of NMR to detect adrenal disease was similar to that of CT in 6 cases examined. CT demonstrated superior spatial resolution in most cases, but NMR provided superior soft-tissue contrast. Since NMR does not involve ionizing radiation and provides excellent soft-tissue differentiation without contrast material, it has advantages over CT and appears to be a promising modality for imaging of the adrenal gland.

Adrenal Gland Diseases↗

The role of single and double-contrast radiography in the diagnosis of reflux esophagitis.

Sixty-seven patients with endoscopically proved esophagitis and 25 patients who had no esophageal disease were examined by double-contrast esophagography, followed by a single-contrast examination. The radiographs were evaluated separately and as a combined examination technique by three independent radiologists in a blind analysis. The respective sensitivities were 77% for the single-contrast examination, 80% for the double-contrast examination, and 88% for the combined examination method with no significant statistical difference (P = 0.05). The sensitivity increased for all methods with an increased severity of esophagitis. False positives more frequently occurred with double-contrast radiography, leading to similar accuracy rates for all methods (74% to 77%). The double-contrast examination technique showed an advantage over single-contrast radiography only if a granular pattern and erosions were the only radiographically detectible features of esophagitis. The use of the combined examination technique is recommended.

Adult↗

Nuclear magnetic resonance imaging of the kidney: renal masses.

Fifteen patients with a variety of renal masses were examined by nuclear magnetic resonance (NMR), computed tomography, ultrasound, and intravenous urography. NMR clearly differentiated between simple renal cysts and other renal masses. On spin echo images, the simple renal cyst appeared as a round or slightly oval, homogeneous low-intensity mass with characteristically long T1 and T2 values. The thickness of the cyst wall was not measurable. The cyst had a smooth outer margin and a distinct, sharp interface with normal parenchyma. Hemorrhagic cysts were seen as high-intensity lesions. Renal cell carcinomas displayed a wide range of intensity. The T1 and T2 values of the tumors were always different from those of the surrounding renal parenchyma. Tumor pseudocapsule was identified in four of five patients examined. All carcinomas were accurately staged by NMR and extension of the tumor thrombus into the inferior vena cava was demonstrated. The authors predict that if these preliminary results are confirmed by data from a larger number of patients, NMR will play a significant role in renal imaging.

Adenocarcinoma↗

Neuroblastoma: diagnostic imaging and staging.

Results of computed tomography (CT), scintigraphy, excretory urography, and other imaging tests used to diagnose and stage 38 cases of neuroblastoma prior to treatment were reviewed. Findings of these examinations were correlated with clinical data, laboratory data, results of biopsy, and surgical findings. CT was the most sensitive single test (100%) for the detection and delineation of the primary tumor. Calcifications that suggested the histologic diagnosis of neuroblastoma were present in 79% of the cases. Rim calcifications, the most specific pattern for neuroblastoma, were identified in 29% of all cases. CT alone accurately staged 82% of cases; when complemented by bone marrow biopsy, staging accuracy was 97%. CT alone was more accurate than any combination of imaging tests that excluded CT. An algorithm using CT is presented for the diagnosis and staging of neuroblastoma at reduced cost and with increased efficiency.

Bone Marrow↗

Recurrent neuroblastoma: the role of CT and alternative imaging tests.

One hundred twelve CT scans of 52 patients who were receiving treatment for neuroblastoma were reviewed for accuracy, and findings were correlated with data obtained from other imaging tests, physical examinations, laboratory tests, biopsies, surgery, and long-term clinical follow-up. CT was the most sensitive imaging test for tumor recurrence (85% detection rate), and it was also the most versatile in the ability to define recurrent disease in the retroperitoneum, liver, cranium, mediastinum, lymph nodes, and skeleton. All 30 tumor recurrences were detected by the combination of CT, bone-marrow biopsy, and selected spot radiographs at the sites of pain. CT was accurate and clinically useful both for assessing tumor response to therapy and for predicting findings at "second look" surgery (accuracy, 94%). CT is relatively cost effective by substituting for a more expensive but less accurate combination of competitive imaging studies.

Adrenal Gland Neoplasms↗

Parathyroid scanning by computed tomography.

Conventional parathyroid computed-tomographic scanning detected 51% (29/57) of tumors averaging 1.5 X 1.0 X 0.8 cm in size at surgery. Forty-six per cent (7/43) of the scans were uninterpretable due to shoulder-streak artifacts. Using a specially designed patient positioning device and a new imaging protocol involving dynamic scanning and the intravenous administration of a bolus of contrast material, 14 patients were scanned; 78% (18/23) of tumors averaging 1.4 X 1.0 X 0.8 cm in size were detected. All 14 scans were interpretable, and image quality was markedly improved.

Contrast Media↗