Photostimulable storage phosphor image acquisition: evaluation of three commercially available state-of-the-art systems.

Photostimulable storage phosphor (PSP) image acquisition systems have been available for several years. The technology has had the opportunity to mature; however, there has not been an independent comparison of recently marketed commercial systems. For this study, three computed radiography (CR) systems using PSP technology (Kodak CR System 400 with autoloader [Eastman Kodak, Rochester, NY], Fuji FCR AC-3CS [Fuji Medical Systems, Stamford, CT], and Agfa ADC Compact [Bayer Corp, Ridgefield Park, NJ]) were connected to an IBM RadWorks diagnostic radiology workstation (IBM Corp, White Plains, NY) and evaluated for conformance to their performance specifications using guidance provided in the most recent draft acceptance testing protocol from Task Group No. 10, American Association of Physicists in Medicine. In addition, the physical requirements (e.g., space and power) and connectivity to another manufacturer's diagnostic workstation were examined. X-ray technologist comfort with each PSP imaging system and an assessment by our supporting biomedical equipment maintenance activity of their ability to service each PSP imaging system were also considered.

Technology assessment and requirements analysis: a process to facilitate decision making in picture archiving and communications system implementation.

In a time of decreasing resources, managers need a tool to manage their resources effectively, support clinical requirements, and replace aging equipment in order to ensure adequate clinical care. To do this successfully, one must be able to perform technology assessment and capital equipment asset management. The lack of a commercial system that adequately performed technology needs assessment and addressed the unique needs of the military led to the development of an in-house Technology Assessment and Requirements Analysis (TARA) program. The TARA is a tool that provides an unbiased review of clinical operations and the resulting capital equipment requirements for military hospitals. The TARA report allows for the development of acquisition strategies for new equipment, enhances personnel management, and improves and streamlines clinical operations and processes.

Single-specimen bile cytology: a prospective study of 80 patients with obstructive jaundice.

PURPOSE: To determine the sensitivity, specificity, and charges associated with single-specimen bile cytologic study in patients with obstructive jaundice. MATERIALS AND METHODS: Eighty consecutive patients with presumed malignant biliary strictures underwent percutaneous biliary drainage (PBD). Cytologic evaluation was performed on a single bile specimen from each patient collected at the time of the PBD. Final diagnoses were obtained from either percutaneous (n = 14) or surgical (n = 66) histologic specimens (gold standard). Both data sets were then compared to determine the sensitivity and specificity of bile cytology. The charges associated with bile cytodiagnosis were compared to those for other biopsy procedures utilized in the same setting. RESULTS: Eighty bile specimens were obtained with a mean of 14 mL (range, 3-65 mL) per patient with 79 (99%) specimens adequate for cytologic processing. Eleven (13%) specimens were acellular. The overall sensitivity was 15% and specificity was 100%; these values were not dependent on the volume of the bile specimen (P > .10) or type of malignancy (P = .10). For bile cytodiagnosis, the mean charge was $160 and the successful biopsy rate (true-positive plus true-negative results/total number procedures) was 27%. CONCLUSION: Single-specimen bile cytology has a low sensitivity; however, because of its convenience, simplicity, atraumatic nature, and low relative charge versus comparable procedures, it may be useful as an adjunct to PBD in patients with suspected malignant biliary disease.

Accurate three-dimensional reconstruction of intravascular ultrasound data. Spatially correct three-dimensional reconstructions.

BACKGROUND: The geometrical accuracy of conventional three-dimensional (3D) reconstruction methods for intravascular ultrasound (IVUS) data (coronary and peripheral) is hampered by the inability to register spatial image orientation and by respiratory and cardiac motion. The objective of this work was the development of improved IVUS reconstruction techniques. METHODS AND RESULTS: We developed a 3D position registration method that identifies the spatial coordinates of an in situ IVUS catheter by use of simultaneous ECG-gated biplane digital cinefluoroscopy. To minimize distortion, coordinates underwent pincushion correction and were referenced to a standardized calibration cube. Gated IVUS data were acquired digitally, and the spatial locations of the imaging planes were then transformed relative to their respective 3D coordinates, rendered in binary voxel format, resliced, and displayed on an image-processing workstation for off-line analysis. The method was tested by use of phantoms (straight tube, 360 degrees circle, 240 degrees spiral) and an in vitro coronary artery model. In vivo feasibility was assessed in patients who underwent routine interventional coronary procedures accompanied by IVUS evaluation. Actual versus calculated point locations were within 1.0 +/- 0.3 mm of each other (n = 39). Calculated phantom volumes were within 4% of actual volumes. Phantom 3D reconstruction appropriately demonstrated complex morphology. Initial patient evaluation demonstrated method feasibility as well as errors if respiratory and ECG gating were not used. CONCLUSIONS: These preliminary data support the use of this new method of 3D reconstruction of vascular structures with use of combined vascular ultrasound data and simultaneous ECG-gated biplane cinefluoroscopy.

Tropical pyomyositis.

A 22-year-old male presented with symptoms of diffuse muscle pain and multiple abnormal laboratory findings that were eventually attributed to tropical myositis. Computed tomography scan was more reliable than ultrasound and served as a guide to needle aspiration and pathologic diagnosis.

Colonic sphincters revisited: simulators of organic disease.

Barium enema examinations establish the presence of neoplastic or inflammatory disease in the colon. Areas of narrowing commonly encountered appear to represent organic disease. These areas are in expected locations throughout the colon and have been described. Not much attention had been given to these areas in recent literature, however, which has led to unnecessary colonoscopies and even surgeries. The sphincters of Rossi, Balli, and Payr-Strauss are involved in nerve reflexes; the sphincters of Hirsch, Moultier, and Busi are a thickening of longitudinal and circular muscle fibers. Cannon's sphincter is an overlap of the superior and inferior mesenteric nerve plexuses. When an area of narrowing is encountered where a known sphincter is located, insufflation of more air, changing patient position, administering 2 mg of glucagon intramuscularly or 0.5 mg to 1 mg intravenously will aid in the distinction between a sphincter and organic disease.

Detection and staging of chondromalacia patellae: relative efficacies of conventional MR imaging, MR arthrography, and CT arthrography.

OBJECTIVE: Chondromalacia patellae is a condition characterized by softening, fraying, and ulceration of patellar articular cartilage. We compare the sensitivity, specificity, and accuracy of conventional MR imaging, MR arthrography, and CT arthrography in detecting and staging this abnormality. SUBJECTS AND METHODS: Twenty-seven patients with pain in the anterior part of the knee were prospectively examined with MR imaging, including T1-weighted (650/16), proton density-weighted (2000/20), T2-weighted (2000/80), and spoiled two-dimensional gradient-recalled acquisition in the steady state (SPGR/)/35 degrees (51/10) with fat saturation pulse sequences. All were also examined with T1-weighted MR imaging after intraarticular injection of dilute gadopentetate dimeglumine and with double-contrast CT arthrography. Each imaging technique was evaluated independently by two observers, who reached a consensus interpretation. The signal characteristics of cartilage on MR images and contour abnormalities noted with all imaging techniques were evaluated and graded according to a modification of the classification of Shahriaree. Twenty-six of the 54 facets examined had chondromalacia shown by arthroscopy, which was used as the standard of reference. The sensitivity, specificity, and accuracy of each imaging technique in the diagnosis of each stage of chondromalacia patellae were determined and compared by using the McNemar two-tailed analysis. RESULTS: Arthroscopy showed that 28 facets were normal. Grade 1 chondromalacia patellae was diagnosed only with MR and CT arthrography in two (29%) of seven facets. Intermediate (grade 2 or 3) chondromalacia patellae was detected in two (13%) of 15 facets with T1-weighted and SPGR MR imaging, in three (20%) of 15 facets with proton density-weighted MR imaging, in seven (47%) of 15 facets with T2-weighted MR imaging, in 11 (73%) of 15 facets with CT arthrography, and in 12 (80%) of 15 facets with MR arthrography. Grade 4 was detected in three (75%) of four facets with T1-, proton density-, and T2-weighted MR imaging, two (50%) of four facets with SPGR MR imaging, and four (100%) of four facets with MR and CT arthrography. Thus, all imaging techniques were insensitive to grade 1 lesions and highly sensitive to grade 4 lesions, so that no significant difference among the techniques could be shown. CONCLUSION: All imaging techniques studied had high specificity and accuracy in the detection and grading of chondromalacia patella; however, both MR arthrography and CT arthrography were more sensitive than T1-weighted, proton density-weighted, and SPGR with fat saturation MR imaging for showing intermediate grades of chondromalacia patellae. Although the arthrographic techniques were not significantly better than T2-weighted imaging, the number of false-positive diagnoses was greatest with T2-weighted MR imaging.

Mesenteric cyst with milk of calcium.

A mesenteric cyst with milk of calcium in an adult patient is presented. Preoperative evaluation included plain film, ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). To our knowledge, the presence of milk of calcium in a mesenteric cyst has not been previously described.

Magnetic resonance imaging with computed tomography of a renal leiomyoma.

Renal leiomyoma are rare, benign tumors of the kidney. There is little information about the imaging of these tumors with modern modalities. We present a case of computed tomographic (CT) and magnetic resonance (MR) imaging of a large renal leiomyoma.