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Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献
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Rosenberg ZS; Jahss MH; Noto AM; Shereff MJ; Cheung Y; Frey CC; Norman A 《Radiology》1988,167(2):489-493
Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture. 相似文献
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M Durdu† S Gökçe‡ M Bagirova§ M Yalaz‡ AM Allahverdiyev§ S Uzun† 《Journal of the European Academy of Dermatology and Venereology》2007,21(2):214-218
OBJECTIVE: Although cutaneous leishmaniasis (CL) occurs mostly in the facial area, periocular involvement accounts for 2-5% of the facial lesions. CL lesions localized in the periocular region can easily be confused with various other diseases. The aim of this study was to examine the frequency of periocular involvement in CL in the Cukurova region of Turkey, as well as the clinical characteristics, diagnosis and methods of treatment of this disease. METHODS: Between December 1998 and December 2004, patients who were diagnosed with CL were evaluated prospectively with respect to periocular involvement. RESULTS: From the 2066 patients evaluated with CL, 2622 lesions were identified. In 59 (2.9%) of these patients, a total of 66 (2.5%) lesions were located in the periocular area. Thirty-two (48.5%) of these lesions were of the papular type, 15 (22.7%) the nodulo-ulcerative type, 10 (15.2%) the plaque type, and nine (13.6%) the nodular type. Dacryocystitis was identified in four patients with periocular involvement. Over the follow-up period, no ocular or periocular deformities or complications developed in these patients. CONCLUSION: Patients suspected of CL should be evaluated and treated early in the course of their disease to prevent any permanent ocular or periocular deformities. 相似文献
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R Dixon AM Hughes K Nairn M Sellers JV Kemp RA Yates 《Cephalalgia : an international journal of headache》1998,18(7):468-475
Zolmitriptan (ZomigTM ) is a 5HT1B/1D agonist which has the ability to cross the intact blood-brain barrier to access central as well as peripheral receptors. Because of the potential for central nervous system side effects, this randomized, double-blind, placebo-controlled, 6-period crossover study evaluated the effects of 2.5 and 5 mg doses of zolmitriptan on psychomotor performance and investigated any pharmacodynamic or pharmacokinetic interaction with diazepam. Twelve healthy volunteers received the following "treatments" as single doses: zolmitriptan 2.5 mg, zolmitriptan 5 mg, diazepam 10 mg, zolmitriptan 2.5 mg+diazepam 10 mg, zolmitriptan 5 mg+diazepam 10 mg and placebo. Pre-dose and at 1, 4, 8, and 24 h post-dose, the following validated battery of psychomotor tests was performed: Bond-Lader visual analogue scales (calmness, contentedness, and alertness factors), critical flicker fusion test, choice reaction time (recognition, motor, and total reaction times), finger-tapping test, number cancellation test and digit symbol substitution test. Plasma concentrations of zolmitriptan, its active metabolite, and diazepam and its active metabolites were measured at the same timepoints. Zolmitriptan 2.5 and 5 mg had no effect on psychomotor function when given alone. In contrast, diazepam 10 mg had profound effects, consistent with its sedative properties, but there was no synergism on concomitant administration of either dose of zolmitriptan. Plasma concentrations of zolmitriptan, diazepam, and their respective active metabolites were similar when the two drugs were given alone or in combination. 相似文献