Although myxoid liposarcoma is a subtype of liposarcoma, it may be difficult to establish the correct diagnosis with magnetic resonance (MR) imaging due to the lack of fat signal intensity. Without the administration of gadolinium contrast material, the tumor may even mimic a cystic tumor. A spectrum of MR imaging abnormalities occur in myxoid liposarcoma, depending on the amount of fat and myxoid material, the degree of cellularity and vascularity, and the presence of necrosis. Most myxoid liposarcomas have lacy or linear, amorphous foci of fat. Some myxoid liposarcomas appear to be cystic at nonenhanced MR imaging, although they enhance like other solid masses at contrast material-enhanced MR imaging. The enhancing areas within the tumor represent increased cellularity and vascularity; the nonenhancing areas represent necrosis, reduced cellularity, and accumulated mucinous material. Gadolinium-enhanced imaging is important in differentiating myxoid liposarcoma from benign cystic tumors. Characterization of the tumor with MR imaging plays an important role in the management of myxoid liposarcoma.

Scapholunate advanced collapse (SLAC) is a pattern of wrist malalignment that has been attributed to posttraumatic or spontaneous osteoarthritis of the wrist. Its features, however, also have been observed in patients with idiopathic calcium pyrophosphate dihydrate (CPPD) crystal deposition disease. To determine the frequency and characteristics of SLAC in this disease, the authors reviewed wrist radiographs in 168 well-documented cases of this disorder. Forty-four of the cases (26%) revealed wrist abnormalities typical of SLAC. Associated findings included bilateral involvement (63%); calcification in or near the triangular fibrocartilage (70%); scapholunate widening or dissociation (70%); and arthropathies of the trapezioscaphoid (57%), metacarpophalangeal (second through fifth) (52%), first carpometacarpal (40%), and radiolunate (14%) joints. Results strongly suggest that CPPD crystal deposition disease is one of the major causes of SLAC. Furthermore, radiolunate arthropathy was found in 14% of the patients with SLAC and CPPD crystal deposition disease, which is different from other observations.

The importance of radiographic evaluation of the scapholunate space, which should not be wider than 2 mm, has been well established in cases of wrist injury. Unfortunately, the assessment of this space is not accurately determined with routine posteroanterior (PA) radiographs, because the scaphoid and lunate bones often overlap. Moreover, the exact portion of the scapholunate space that should be measured has never been clearly defined. Nine wrists with a scapholunate space no wider than 2 mm and without chondrocalcinosis were studied by means of plain routine views and special projections, transaxial and coronal computed tomographic scans, and dissection to determine the precise orientation and anatomy of this space. A PA radiograph with 10 degrees of tube angulation from the ulna toward the radius best demonstrated the scapholunate space. This space should be measured at the level of the midportion of the flat lateral facet of the scaphoid.

Although the radiologic manifestations of degenerative disease of the knee have been investigated, the distribution of marginal and central osteophytes has not been defined. This study included (a) 50 consecutive patients with osteoarthritis of the knee in whom routine and specialized projections were obtained prospectively, (b) 25 patients with calcium pyrophosphate dihydrate (CPPD) crystal deposition disease whose knee radiographs were retrospectively reviewed, and (c) four cadaveric knees that were dissected to assess pertinent anatomy. In this study the importance of the tunnel view in the evaluation of osteoarthritis and CPPD crystal deposition disease is demonstrated, the distribution of and the relationship between marginal and central osteophytes are discussed, and two new radiologic signs are described. As both marginal and central osteophytes may simulate intraarticular bodies, the recognition of these outgrowths is of clinical importance.

To evaluate the diagnostic value of MR imaging in ca엄5 of spinal tuberculosis, twenty patients with advanced spinal tuberculosis were examined by MR imaging μ 2.0T (Spectro-20000, GoldStar, Seoul). Eighteen of 20 patients underwent surgery and the diagnosis was confirmed bacteriologically or histologically. Various spinecho p비 se sequences were used in coronal and sagittal planes. lnflammatory tissue showed relatively low singal intensity on TI-weighted images and high signal intensity on T2-weighted images. The bone destruction and disc-space involvement were well visualized in both coronal and sagittal planes. The abscess cavity was distinguish-