Feasibility of single-voxel MRS measurement of apparent diffusion coefficient of water in breast tumors.

We report initial results with single voxel spectroscopy (SVS) using diffusion weighting and localization by adiabatic selective refocusing (LASER) in breast tumors to measure the apparent diffusion coefficient of water (ADCw). This is a quick (30 s) and relatively easy method to implement compared with image-based diffusion measurements, and is insensitive to lipid signal contamination. The ADCw and concentration of total choline containing compounds [tCho] were evaluated for associations with each other and final pathologic diagnosis in 25 subjects. The average (+/- SD) ADCw in benign and malignant lesions was 1.96 +/- 0.47 mm(2)/s and 1.26 +/- 0.29 x 10(-3) mm(2)/s, respectively, P< 0.001. Receiver operating characteristic curve analysis showed an area under the curve of 0.92. Analysis of the single voxel (SV) ADCw and [tCho] showed significant correlation with a R(2) of 0.56, P< 0.001. Compared with more commonly used image-based methods of measuring water ADC, SV-ADCw is faster, more robust, insensitive to fat, and potentially easier to implement on standard clinical systems.

Ruptured or intact: what can linear echoes within silicone breast implants tell us?

OBJECTIVE: During sonographic evaluation of silicone breast implants for possible rupture, we have frequently encountered several patterns of linear echoes within the implants. To our knowledge, the significance of this finding has not been established in the literature. The purpose of this study was to determine whether internal echoes are significant in predicting implant rupture. SUBJECTS AND METHODS: Thirty-three patients with 64 silicone implants were prospectively entered into a study that included gray-scale sonography of the implants and subsequent surgical removal. Echo patterns within the implants were retrospectively evaluated on hard-copy films and compared with the integrity of the implant at surgery. RESULTS: Three categories of internal echo patterns were identified: "thick linear echoes." "thin linear echoes," and "commas." One or more of these echo patterns were seen in 57 (89%) of the 64 implants. Thick linear echoes were seen in 23 (36%) of the 64 implants, thin linear echoes were seen in 33 (52%) of the 64 implants, and commas were seen in 47 (73%) of the 64 implants. All echo patterns were seen in intact and ruptured implants with nearly equal frequency. We found no statistical significance for any echo pattern in predicting whether an implant was ruptured or intact. Of the 64 implants, four were entirely free of internal echoes. All four implants were intact. CONCLUSION: A variety of linear echoes can be seen in most silicone breast implants on gray-scale sonography. The presence or absence of linear echoes is not useful in predicting implant rupture. Complete absence of internal echoes, while highly predictive of an intact implant, is infrequently seen.

Hyperextension strain or "whiplash" injuries to the cervical spine.

PURPOSE: To define "whiplash" radiologically. MATERIAL AND METHODS: A full cervical spine radiographic series (including flexion and extension views) was reviewed in 40 patients with clinically proven "whiplash" injuries and compared to the radiographs in 105 normal controls. The level and degree of kinking or kyphosis, subluxation, and the difference in the amount of fanning between spinous processes on flexion and extension films were measured in each patient. RESULTS: Localized kinking greater than 10 degrees and over 12 mm of fanning, often occurring at the level below the kinking or kyphosis, occurred mainly in the group of whiplash patients (sensitivity 81%, specificity 76%, accuracy 80%). CONCLUSIONS: Localized kinking greater than 10 degrees and fanning greater than 12 mm are useful measurements by which to separate patients with true whiplash injuries from those with minor ligamentous tears. Flexion and extension views are essential to help define whiplash and other ligamentous injuries of the cervical spine.

The radiology of total shoulder replacement.

The indications for total shoulder replacement and the radiologic evaluation prior to the operation are discussed in depth in this article. Different approaches to clinical problems are also discussed and illustrated, as are normal findings. This is followed by a discussion of the complications of shoulder reconstruction, including infection, fractures, and heterotopic bone formation. A review of the results is also given followed by a brief mention of a number of other orthopedic shoulder devices and plates.

Diagnosis of breast implant rupture: imaging findings and relative efficacies of imaging techniques.

OBJECTIVE: The purpose of this study was to compare the efficacies of mammography, sonography, CT, and MR imaging in the detection of breast implant rupture and to analyze the imaging findings. SUBJECTS AND METHODS: Thirty-two women with 63 silicone breast implants participated in the study. All but one had signs and symptoms suggestive of rupture, and all had requested that their implants be removed before they were enrolled in this imaging study. All patients had film-screen mammography, sonography, CT, and MR imaging. Twenty-two ruptures were found at surgery; 21 were intracapsular and one was extracapsular. The relative efficacies of the imaging studies were determined, and the imaging findings were compared with the surgical results. RESULTS: Of the 32 women with 63 implants, mammographic sensitivity for detecting implant rupture was only 23% but the specificity was 98%. Sonography had a higher sensitivity (59%), but its specificity was significantly lower (79%). CT had a sensitivity of 82% and a specificity of 88%. MR was the only imaging technique that consistently provided evidence that enabled the evaluation of intracapsular and extracapsular ruptures. The sensitivity and specificity of MR imaging were 95% and 93%, respectively. CONCLUSION: Our results show that MR imaging is more sensitive and specific for the detection of breast implant rupture than is mammography, CT, or sonography.

Staging of musculoskeletal tumors.

Staging of musculoskeletal neoplasms is important for planning chemotherapy and surgical procedures. Accurate staging has increased in importance with advancements in limb salvage procedures. This article outlines concepts, techniques, and potential problems with staging of neoplasms. It is important to remember that biopsy should be preformed after consultation with an orthopedic surgeon specialized in tumor surgery.

Radiologic case study. MRI in the diagnosis of synovial disease.

Fourteen patients with various synovial diseases were imaged using conventional radiographic techniques and MRI. We had five patients with synovial tumors, including two each with PVNS and synovial osteochondromatosis. We had five patients with infections and four patients with various other forms of arthritis. Although MRI was found to be a useful means to visualize the synovium, the findings were nonspecific except in the case of PVNS.

Peripheral (extracranial) nerve tumors: correlation of MR imaging and histologic findings.

Magnetic resonance (MR) images of 16 peripheral nerve tumors (14 patients) were correlated with histopathologic appearance. Thirteen patients had surgically proved neuro-fibromatosis. There were 10 neurofibromas, four schwannomas, and two neurofibrosarcomas. Seven of the 10 neurofibromas showed a target pattern of increased peripheral signal intensity and decreased central signal intensity on T2-weighted images. This pattern appeared to correspond to a distinctive zonal histologic appearance that was found only in the neurofibromas. This pattern was not seen on MR images of the other peripheral tumors.

Bursitis in association with solitary osteochondromas presenting as mass lesions.

Three patients with solitary osteochondromas which were increasing in size have been recently examined. Plain films were available on all patients; two patients had MR studies, and two had CT scans. In all three cases, malignant transformation of the osteochondroma was suspected from the cross-sectional imaging studies, but pathologic examination proved that these patients all had bursa formation without any evidence of malignancy. The incidence of this rare complication of solitary osteochondroma is discussed. Ultrasound is also recommended for the evaluation of enlarging solitary osteochondromas.