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991.
992.
Biliary tract: three-dimensional helical CT without cholangiographic contrast material 总被引:13,自引:0,他引:13
Zeman RK; Berman PM; Silverman PM; Cooper C; Garra BS; Patt RH; Ascher SM 《Radiology》1995,196(3):865
993.
Cunningham JM; Purucker ME; Jane SM; Safer B; Vanin EF; Ney PA; Lowrey CH; Nienhuis AW 《Blood》1994,84(4):1298-1308
994.
Six hundred forty-five cases of transitional cell carcinoma (TCC) of the bladder, ureter, and/or kidney were reviewed retrospectively to determine the frequency of synchronous and metachronous lesions elsewhere in the urinary tract. Among 597 patients with TCC of the bladder, 23 (3.9%) developed an upper-tract lesion, after an average delay of 61 months. Metachronous upper-tract tumors developed in 13% of 38 patients with primary ureteral TCC and in 11% of 63 with renal TCC, after average delays of 28 and 22 months, respectively. Synchronous TCC was found in 2.3% of patients with bladder TCC, 39% of those with ureteral TCC, and 24% of those with renal TCC. Seventeen percent of the subsequent upper-tract lesions would have been demonstrated by intravenous or retrograde urography performed 1 year after the initial onset of primary bladder cancer, and 61% would have been demonstrated by studies performed within 2 years. Therefore, the authors recommend annual radiologic evaluation of the upper urinary tract for 2 years after initial diagnosis and treatment of an upper-tract or bladder TCC. 相似文献
995.
Clinical application of in vitro studies for barium-enema examination following colorectal biopsy 总被引:2,自引:0,他引:2
Harned RK; Williams SM; Maglinte DD; Hayes JM; Paustian FF; Consigny PM 《Radiology》1985,154(2):319-321
A total of 150 colorectal biopsies were performed in 71 patients and correlated with the barium-enema examination (BE). The investigation was divided into two parts. In the first part, involving 19 patients, the depth of each biopsy specimen was determined histologically prior to BE and potential complications related to the biopsy-BE sequence were evaluated. In the second part, involving all 71 patients, the depth of biopsy specimens taken from various colon lesions was determined histologically without regard to the timing of BE. The results confirm previous in vitro findings in pigs and dogs, namely: (a) BE may be performed without delay following a superficial biopsy, but should not be performed until at least 6 days after a deep biopsy; (b) transcolonoscopic biopsies are likely to be superficial, while transproctoscopic biopsies have the potential to be deep; and (c) BE should be delayed at least 6 days following polypectomy or polyp biopsy performed with electrosurgery. 相似文献
996.
Leptomeningeal metastasis: MR imaging 总被引:3,自引:0,他引:3
Seven patients with central nervous system neoplasia and leptomeningeal metastases, proved either at initial diagnosis or on follow-up with contrast material-enhanced computed tomography (CT), were evaluated with magnetic resonance (MR) imaging. In two patients, diffuse sulcal enhancement on CT scans was inapparent on T1- or T2-weighted MR images. Likewise, in four patients diffuse cisternal enhancement on CT scans was not identifiable with MR. Nodular or focal cisternal masses were identified with both CT and MR imaging in three patients; in two, however, MR imaging provided less information. Ependymal and subependymal metastases identified with CT (two patients) were indistinguishable on MR images from periventricular abnormalities of radiation therapy and/or hydrocephalus. These findings suggest that leptomeningeal metastasis may be so subtle or inapparent as to be overlooked with MR imaging alone. Thus, CT and MR imaging should be considered complementary techniques for initial diagnosis and follow-up of tumors with a propensity for leptomeningeal metastasis. 相似文献
997.
998.
Magnetic resonance (MR) images of 28 normal temporomandibular joints were obtained and correlated with respective arthrograms. There was a spectrum in the configuration and thickness of normal articular menisci. The anterior band varied from thin with a flat inferior margin to thick with a bulbous, convex inferior margin. The anatomic configuration of the meniscus as seen with MR correlated directly with normal variations of the anterior recess seen with arthrography. Concavity of the superior aspect of the anterior recess as seen on arthrography was caused by a thick, bulbous anterior band of the meniscus, whereas a flat anterior recess resulted from a thin anterior band without a convex inferior margin. This study emphasizes that the appearance of a concave anterior recess on static arthrograms is not necessarily due to a displaced meniscus. 相似文献
999.
Sharif HS; Aideyan OA; Clark DC; Madkour MM; Aabed MY; Mattsson TA; al-Deeb SM; Moutaery KR 《Radiology》1989,171(2):419-425
Radiographs, scintigrams, computed tomographic scans, and magnetic resonance (MR) images of 17 patients with brucellar spondylitis and 15 with tuberculous spondylitis were analyzed to identify distinguishing features. Characteristic findings of brucellar spondylitis included predilection for the lower lumbar spine (68% of lesions), bone destruction limited to the end plates, disk collapse (16 of 19 disks), and granulation tissue or localized soft-tissue edema (17 of 19 sites). MR imaging showed diffuse increased signal in vertebrae and disks on long repetition time (TR)/echo time (TE) images in four patients and focal increased signal with normal disks in one. Epidural extension was best seen on short TR/TE images in four. Tuberculous spondylitis was characterized by predilection for the midthoracic spine (73%), vertebral destruction with gibbus deformity (60%), disk collapse, and paraspinal abscesses (14 of 15). On MR images signal intensity of affected vertebrae was similar to but more severe than findings in patients with brucellar spondylitis. Scintigraphy was the least helpful in differentiating the two infections. Lesions of tuberculous spondylitis affecting the lower lumbar spine were difficult to differentiate from those of brucellar spondylitis. 相似文献
1000.
Artifacts related to barium flow during double-contrast esophagography may obscure mucosal surface details. Double-contrast esophagograms with flow artifacts of 35 patients were evaluated to determine the effect on radiographic interpretation and to assess the method of examination. Initial radiographs obtained during swallowing of barium were compared with those obtained after a slight delay while patients repeatedly dry swallowed. When severe surface flow artifacts were present, the extent of mucosal disease was underestimated in all cases. Mild surface flow artifacts interfered with the demonstration of the reticular pattern of Barrett esophagus, and luminal flow artifacts caused misinterpretation. The demonstration of strictures was unaffected by flow artifacts. This study suggests that the dry swallowing maneuver and some delay improve depiction of esophageal surface details on double-contrast radiographs and obviate interpretive error from barium flow artifacts. 相似文献