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101.
Eric K. Outwater Katsuyoshi Ito Evan Siegelman C. Edwin Martin Manoj Bhatia Donald G. Mitchell 《Journal of magnetic resonance imaging : JMRI》1997,7(6):1033-1039
The purpose of this study is to describe a subset of atypical hepatic hemangiomas that enhance rapidly and diffusely and to determine whether heavily T2-weighted images could distinguish between atypically enhancing liver hemangiomas and hypervascular malignancies. A retrospective search of MR records identified seven patients with liver hemangiomas that demonstrated diffuse early enhancement and 23 patients with biopsy-proven malignant liver lesions that were hypervascular on dynamic gadolinium-enhanced MR images. Quantitative analysis of signal intensity measurements was performed on the T2-weighted images, heavily T2-weighted (TE < 140), and dynamic gadolinium-enhanced images. Blinded reader comparison of the T2-weighted images and gadolinium-enhanced images was performed. Hypervascular hemangiomas enhanced to a greater degree than hypervascular malignant liver lesions on the early phase gadolinium-enhanced images. Perilesional parenchymal enhancement was demonstrated in five cases of rapidly enhancing hemangiomas. Signal intensity and contrast-to-noise ratios on the heavily T2-weighted images of the hemangiomas were significantly greater than that of the hypervascular malignant lesions (P < .05). Hemangiomas were differentiated from the hypervascular malignant liver lesions with high accuracy (97–100%) by three blinded readers based on the T2-weighted images. A subset of hemangiomas have atypical rapid diffuse enhancement on dynamic gadolinium-enhanced images. These atypical hemangiomas can be distinguished from hypervascular malignant liver lesions on T2-weighted MR images. 相似文献
102.
瘤体骨切除灭活再植治疗四肢长骨巨细胞瘤 总被引:21,自引:0,他引:21
体内刮除及灭活植骨治疗骨巨细胞瘤(GCT)的复发率高。我科从1986年6月~1996年2月治疗四肢长骨GCT24例。随访11个月~8年4个月。其中7例采用局部切刮体内灭活植骨和(或)骨水泥充填治疗。结果1例感染,6例复发,1例恶变后死于肺转移。作者自1991年1月采用瘤体骨切除,离体灭活再植,与骨残端体内灭活相结合,骨缺损采用自家腓、髂骨移植,L-梯形加压钢板(L-TCP)或梯形加压钢板(TCP)固定治疗17例,其中12例保留关节,5例做膝关节融合。本组无菌创口感染1例,1例复发。在保留关节的12例中9例关节功能恢复优良,1例尚可,2例差。充分说明瘤段骨切除体外灭活再植术疗效确实,复发率低。保留关节术式适于关节破坏较轻(<=1/2)者,结合关节残端体内灭活和有效的骨结构重建,有利于恢复关节功能。如关节面累及>1/2,宜做骨关节端切除,灭活再植,下肢宜做关节融合或人工关节置换术。 相似文献
103.
F. D. Knollmann J. C. Bck S. Teltenktter W. Wlodarczyk A. Mühler Th. J. Vogl R. Felix 《Journal of magnetic resonance imaging : JMRI》1997,7(1):191-196
The purpose of our research was to determine the effects of superparamagnetic iron oxide on MR imaging of the portal venous system. Eight piglets were examined in deep anaesthesia and respiratory arrest using a time-of-flight magnetic resonance fast low angle shot, two-dimensional angiography sequence at 1.5T. MR angiograms were acquired precontrast and after intravenous administration of a cumulative dose of 10, 20 and 40 μmol/kg SHU 555A, a superparamagnetic iron oxide contrast agent for MR imaging with a particle size of 60 nm. For each dose, two subsequent sets of scans were obtained and reconstructed by a maximum-intensity-projection algorithm. Hepatic parenchymal and portal venous signal intensities were measured, and portal vein contrast calculated for each set of scans. All examinations were visually rated as to portal vein contrast and homogeneity by two blinded observers. Receiver operating characteristics of both observers were analyzed. The contrast agent reduced hepatic parenchymal signal in a dose-dependent way. After a cumulative dose of 10 μmol iron oxide, hepatic parenchymal signal intensity decreased to 63 ± 6% (average of measurements at 4 and 14 minutes, mean ± standard error of the mean), after 20 μmol to 24 ± 3%, and after 40 μmol to 12 ± 1% of control. Intra-vascular signal in the left main portal vein branch increased to 117 ± 6%, 127 ± 10%, and 133 ± 9% of control, respectively. The contrast-to-noise ratio of the portal vein improved (521 ± 90%, 891 ± 178%, and 995 ± 201% of control in the left portal vein main branch). Intravascular signal intensities increased slightly. The combined effect improved contrast of the portal vein stem and its branches. Receiver operating characteristics analysis documented dose-dependency of contrast medium effects on portal venous contrast and intravascular homogeneity. Visual rating also indicated a positive effect on portal venous contrast. The superparamagnetic iron oxide agent improved portal venous contrast with surrounding hepatic parenchyma in this normal animal model, and could potentially result in more accurate diagnosis of portal venous pathology. 相似文献
104.
Andrea Veltri Simona Capello Barbara Faissola Francesco Spalluto Sergio Farinet Maurizio Grosso 《Cardiovascular and interventional radiology》1994,17(3):133-137
Purpose The goal of the study is to evaluate utility of contrast enhanced ultrasound (US) with carbon dioxide microbubbles in evaluation of hepatic lesions.Methods Twenty eight patients with single or multiple t hepatic lesions (11 hepatocellular carcinoma, 8 hemangiomas, 5 metastases, 1 adenoma, 1 focal nodular hyperplasia, 2 regenerative nodules) were examined. US exam was performed during intraarterial injection of 10 ml of CO2 through the same catheter employed for liver arteriography. The US exam was videotaped in its salient phases. Characteristics of enhancement were evaluated and correlated with histological findings or patient follow up.Results Sonographic angiography clearly demonstrated vascularization of the lesions. Hepatocellular carcinoma, hemangioma, metastases, focal nodular hyperplasia, and regenerative nodules had very characteristic patterns. The injection of CO2 allowed detection of small additional nodules.Conclusion Sonographic angiography can improve characterization and staging of hepatic tumors. Low cost and the simplicity of the technique should encourage further experimentation. 相似文献
105.
Richard Simpson Catherine Kennedy Hugh Carmalt Brian McCaughan David Gillett 《ANZ journal of surgery》1997,67(10):717-719
Background : A patient with a solitary pulmonary metastasis who had breast cancer in the past may benefit from pulmonary resection. Methods : Between 1984 and 1996, 17 patients underwent metastatectomy for metastatic breast cancer. There were 15 females and two males whose average age was 59 (range: 40–74 years). The median tumour-free interval after the primary breast-cancer operation was 5.1 years (range: 8 months-18.2 years). Sixteen patients had complete resections, which included six lobectomies and 10 lesser resections. Results : The postoperative mortality was nil and the morbidity rate was 6%. Follow-up was complete in all patients. Recurrent disease developed in four patients and two patients died of their disease. The 5-year survival was 62%. Conclusion : An aggressive surgical approach is warranted in patients with isolated resectable pulmonary metastases from breast cancer. 相似文献
106.
Toshifumi Gabata Osamu Matsui Masumi Kadoya Jun Yoshikawa Kazuhiko Ueda Yasuhiro Kawamori Tsutomu Takashima 《Journal of magnetic resonance imaging : JMRI》1997,7(5):855-857
The purpose of this study was to determine the relationship between segmental hyperintensity of the liver on T1-weighted images and segmental cholestasis in patients with obstructive jaundice. T1-weighted and T2-weighted MR images were obtained of 73 patients with obstructive jaundice caused by various diseases. Fat-suppressed T1-weighted images were also obtained of 10 patients. Eleven patients with segmental intra-hepatic bile duct dilatation (cholestasis) showed segmental hyperintensity on T1-weighted images and/or fat-suppressed T1-weighted images and no signal intensity difference on T2-weighted images. Sixty-two patients with widespread intrahepatic bile duct dilatation showed no intensity difference on T1-weighted and T2-weighted images (P < .01). Segmental hyperintensity on T1-weighted images was correlated with intrahepatic cholestasis. 相似文献
107.
生长激素在肝硬变门脉高压低蛋白血症手术前的应用研究 总被引:1,自引:1,他引:0
目的:研究生长激素(rhGH)对肝硬变门脉高压低蛋白血症患者手术前的治疗价值。方法:肝硬变门脉高压抑行脾切除、门奇静脉断流手术患者60例,Child分级B级,随机分为rhGH治疗组30例,对照组30例。rhGH组术前5d每天皮下注射rhGH 4IU,对照组给予安慰剂生理盐水。两组术前均行相同肠外营养支持。测定治疗前、治疗后3d、4d、5d血浆白蛋白、球蛋白、前白蛋白及空腹血糖。结果:rhGH组治疗后3d前白蛋白较治疗前及对照组明显升高(P<0.05),治疗后4d、5d仍维持较高水平;治疗后5d白蛋白较治疗前及对照组明显升高(P<0.05)。rhGH组患者一般情况改善,生活质量提高。对照组白蛋白、前白蛋白无明显变化。两组空腹血糖、球蛋白无明显改变。结论:rhGH联合肠外营养支持对纪正肝硬变门脉高压低蛋白血症患者术前低蛋白状态,改善生活质量有良好疗效,由于rhGH起效慢,应早期、足量、足疗程应用。 相似文献
108.
Radhika Srinivasan Raje Nijhawan Upasana Gautam Pradeep Bambery 《Diagnostic cytopathology》1994,10(4):383-384
A case of primary amyloidosis, initially detected by fine-needle aspiration of the liver, is reported here. Amorphous acellular metachromatic material was seen extracellularly in between the hepatocytic cords compressing them. This material showed typical apple-green birefringence under crossed bipolars after alkaline Congo-red staining proved its amyloid nature. It was resistant to potassium permanganate pretreatment, indicating it to be of the AL type. © 1994 Wiley-Liss, Inc. 相似文献
109.
Katsunobu Kawahara Takeshi Shiraishi Kan Okabayashi Akinori Iwasaki Yasuteru Yoshinaga Kouji Hayashi Jyunichi Yamashita Takayuki Shirakusa 《Surgery today》1997,27(2):163-165
A patient with a recurrent tumor in the trachea adjacent to the right main bronchus was treated by surgical resection 19 months
after undergoing surgery for the primary cancer. The patient had previously undergone right upper lobectomy for T1N0M0 stage
I squamous cell carcinoma. A carinal resection was performed which included 4 rings of the trachea, 2 rings of the righ main
bronchus, and 1 ring of the left main bronchus. Reconstruction consisted of an end-to-end anastomosis of the trachea and left
main bronchus, and an end-to-side anastomosis of the right and left main bronchi. The postoperative course was uneventful,
and at present the patient is healthy 12 months following reoperation. 相似文献
110.
David S. K. Lu Shantanu Sinha John Lucas Keyvan Farahani Robert Lufkin Klaus Lewin 《Journal of magnetic resonance imaging : JMRI》1997,7(2):303-308
The purpose of this study was to test the feasibility of MR-guided percutaneous ethanol ablation of liver tissue on a .2-T open MR scanner. Needles were placed by MR guidance first into an ex vivo sheep liver and then into livers of three anesthetized pigs, and injection of 10 ml of 96% alcohol was performed. T1 fast low-angle shot (FLASH), T2 turbo spin echo (TSE), and T1 spin echo (SE) images were obtained after incremental volumes of injection. In one pig, simultaneous injection of saline into normal liver was also performed with subsequent pathological correlation. Ethanol-infiltrated liver was hypointense to liver on all sequences, whereas saline caused no tissue signal changes on T1 SE and either isointense or hyperintense changes on T2 TSE images. Pathological examination confirmed ethanol-induced acute liver changes as compared with the control. MR guidance of needle placement and monitoring of ethanol effects on liver tissue is feasible. This may have implications for potential MR-guided hepatic tumor ablation. 相似文献