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931.
Bahn E Wiltfang J Nolte W Ramadori G Steinhoff B Rüther E Kurth C 《Metabolic brain disease》2005,20(1):1-6
We examined a 41-year-old female with a subacute Budd-Chiari Syndrome (BCS) before and after implantation of a transjugular intrahepatic portosystemic stent shunt (TIPSS) by means of digital electroencephalography (EEG). After TIPSS implantation hepatic decompression had been achieved and the liver function as well as the clinical status improved daily. Simultaneously, the digital EEG showed a decrease in the power of the theta band and an increase in the physiological alpha frequency band. The theta/alpha ratio decreased after TIPSS, despite an elevated arterial ammonia level. The patient had a well-preserved liver parenchyma before the occurrence of the BCS. After portal decompression by TIPSS, the liver function normalized and the liver resumed efficient synthesis and parts of its detoxification task. This regeneration capacity was documented by a rise in cholinesterase after TIPSS. After temporary substitution of albumin the serum albumin concentration returned to normal. Thus, some neurotoxic substances with high albumin-binding capacity may not be absorbed by the central nervous system (CNS). Furthermore, it appears likely that the length of time the brain is exposed to neurotoxic substances plays a role in the clinical and electroencephalographic changes. Compared to the conventional EEG the theta/alpha ratio reflected better metabolically conditioned electroencephalographic changes after TIPSS. 相似文献
932.
Navarro S Del Hoyo P Campos Y Abitbol M Morán-Jiménez MJ García-Bravo M Ochoa P Grau M Montagutelli X Frank J Garesse R Arenas J de Salamanca RE Fontanellas A 《Experimental dermatology》2005,14(1):26-33
Mitochondrial dysfunction might play a role in the pathogenesis of liver damage in erythropoietic protoporphyria (EPP). Changes in mitochondrial respiratory chain activities were evaluated in the Fech(m1pas)/Fech(m1pas) mouse model for EPP. Mice from different strains congenic for the same ferrochelatase germline mutation manifest variable degrees of hepatobiliary injury. Protoporphyric animals bred into the C57BL/6J background showed a higher degree of hepatomegaly and liver damage as well as higher protoporphyrin (PP) accumulation than those bred into the SJL/J and BALB/cJ backgrounds. Whereas mitochondrial respiratory chain activities remained unchanged in the liver of protoporphyric mice C57BL/6J, they were increased in protoporphyric mice from both SJL/J and BALB/cJ backgrounds, when compared to wild-type animals. Mitochondrial respiratory chain activities were increased in Hep G2 cell line after accumulation of PP following addition of aminolevulinic acid. As a direct effect of these elevated mitochondrial activities, in both hepatic cells from mutant mouse strains and Hep G2 cells, adenosine 5'-triphosphate (ATP) levels significantly increased as the intracellular PP concentration was reduced. These results indicate that PP modifies intracellular ATP requirements as well as hepatic mitochondrial respiratory chain enzymatic activities and further suggest that an increase of these activities may provide a certain degree of protection against liver damage in protoporphyric mice. 相似文献
933.
Multi-detector computed tomography angiography of the hepatic artery in liver transplant recipients 总被引:5,自引:0,他引:5
Boraschi P Donati F Cossu MC Gigoni R Vignali C Filipponi F Bartolozzi C Falaschi F 《Acta radiologica (Stockholm, Sweden : 1987)》2005,46(5):455-461
Purpose: To evaluate the ability of multi-detector row computed tomography angiography (CTA) in detecting hepatic artery complications in the follow-up of liver transplant patients, performing volume-rendering as reconstruction technique.
Material and Methods: The anatomy of hepatic artery was studied in 27 liver transplant recipients with a four-row CT scanner using the following parameters: collimation, 1 mm; slice width, 1 mm; table feed, 6-8 mm/s; spiral reconstruction time, 0.5 s; reconstruction interval, 0.5 mm; mAs, 160; kVp, 120. Before the study, the patients received 1000 ml of water as oral contrast agent to produce negative contrast in the stomach and the small bowel. A non-ionic contrast medium was infused intravenously at a rate of 5 ml/s with a bolus tracking system. Volume-rendering of hepatic artery was performed with the 3D Virtuoso software.
Results: The celiac trunk, the hepatic artery, and the right and left hepatic arteries were successfully displayed in high detail in all patients. Side branches, including small collaterals, and hepatic artery anastomosis could also be readily visualized. Volume-rendered CTA detected six hepatic artery stenoses, two hepatic artery thromboses, and two intrahepatic pseudoaneurysms. In two cases, CT detected hepatic artery stenosis with a diameter reduction of less than 50%, while digital subtraction angiography showed a normal artery.
Conclusion: Volume-rendered multi-detector CTA is a promising non-invasive technique, since it allows images of high quality to be generated with excellent anatomical visualization of the hepatic artery and its complications in liver transplant recipients. 相似文献
Material and Methods: The anatomy of hepatic artery was studied in 27 liver transplant recipients with a four-row CT scanner using the following parameters: collimation, 1 mm; slice width, 1 mm; table feed, 6-8 mm/s; spiral reconstruction time, 0.5 s; reconstruction interval, 0.5 mm; mAs, 160; kVp, 120. Before the study, the patients received 1000 ml of water as oral contrast agent to produce negative contrast in the stomach and the small bowel. A non-ionic contrast medium was infused intravenously at a rate of 5 ml/s with a bolus tracking system. Volume-rendering of hepatic artery was performed with the 3D Virtuoso software.
Results: The celiac trunk, the hepatic artery, and the right and left hepatic arteries were successfully displayed in high detail in all patients. Side branches, including small collaterals, and hepatic artery anastomosis could also be readily visualized. Volume-rendered CTA detected six hepatic artery stenoses, two hepatic artery thromboses, and two intrahepatic pseudoaneurysms. In two cases, CT detected hepatic artery stenosis with a diameter reduction of less than 50%, while digital subtraction angiography showed a normal artery.
Conclusion: Volume-rendered multi-detector CTA is a promising non-invasive technique, since it allows images of high quality to be generated with excellent anatomical visualization of the hepatic artery and its complications in liver transplant recipients. 相似文献
934.
Frezza EE 《Digestive diseases and sciences》2004,49(5):866-871
The treatment of hepatic tumors in cirrhotic and noncirrhotic patients still represents a major issue in decision making for oncologists and surgeons. The high mortality of open liver surgery, particularly in cirrhotic patients, has pushed physicians to research new modalities. In this review paper we summarize the available and alternative methods for the treatment of liver masses using new modalities and a minimally invasive approach, which will benefit the quality of life of the patients. We also outline therapeutic plan options. 相似文献
935.
Numerous studies over the past decade have shown that magnetic resonance imaging (MRI) has great potential for detecting and quantifying the distribution of iron in the body. With MRI, tissue iron is indirectly identified by the paramagnetic effects of iron on the shortening of water proton MR relaxation times. However, these effects are complex and involve a number of factors, such as tissue hydration, distribution of iron and water within the tissue, and the amount of iron loading within the iron storage molecules. A coherent understanding of how these factors influence the MRI signal is still lacking. The dependence on experimental conditions, such as magnet field strength, pulse sequences, and data acquisition parameters, further complicates iron quantification with MRI. To date, there is no generally accepted MRI approach available for clinical application. In this review, we first explain the basic MR relaxation mechanisms underlying the detection of iron with MRI. We then review the literature on empirical MRI studies of hepatic iron. Finally, we summarize the critical issues that need to be addressed to develop MRI techniques for non-invasive iron detection in the body. 相似文献
936.
Nakagawa Y Matsumura K Iwasa M Kaito M Adachi Y Takeda K 《Annals of nuclear medicine》2004,18(2):123-129
OBJECTIVE: The early diagnosis and treatment of cognitive impairment in cirrhotic patients is needed to improve the patients' daily living. In this study, alterations of regional cerebral blood flow (rCBF) were evaluated in cirrhotic patients using statistical parametric mapping (SPM). The relationships between rCBF and neuropsychological test, severity of disease and biochemical data were also assessed. METHODS: 99mTc-ethyl cysteinate dimer single photon emission computed tomography was performed in 20 patients with non-alcoholic liver cirrhosis without overt hepatic encephalopathy (HE) and in 20 age-matched healthy subjects. Neuropsychological tests were performed in 16 patients; of these 7 had minimal HE. Regional CBF images were also analyzed in these groups using SPM. RESULTS: On SPM analysis, cirrhotic patients showed regions of significant hypoperfusion in the superior and middle frontal gyri, and inferior parietal lobules compared with the control group. These areas included parts of the premotor and parietal associated areas of the cortex. Among the cirrhotic patients, those with minimal HE had regions of significant hypoperfusion in the cingulate gyri bilaterally as compared with those without minimal HE. CONCLUSIONS: Abnormal function in the above regions may account for the relatively selective neuropsychological deficits in the cognitive status of patients with cirrhosis. These findings may be important in the identification and management of cirrhotic patients with minimal HE. 相似文献
937.
The authors report the case of a grade 4 liver laceration caused by blunt abdominal trauma. The liver injury was managed nonoperatively, both initially and after an episode of delayed hemorrhage. The patient suffered 2 additional as yet unreported complications of pediatric liver injury: a right pleural effusion causing respiratory embarrassment followed by duodenal obstruction; the latter was caused by hypertrophy of the left lobe of the liver. Although numerous reports suggest that delayed hemorrhage after pediatric liver injury should be managed operatively, the mortality of such intervention remains high, reaffirming the dictum that one must treat the patient and not the injury. 相似文献
938.
Significance of total vascular exclusion for hepatic cryotherapy: an experimental study 总被引:3,自引:0,他引:3
Jungraithmayr W Szarzynski M Neeff H Haberstroh J Kirste G Schmitt-Graeff A Farthmann EH Eggstein S 《The Journal of surgical research》2004,116(1):32-41
BACKGROUND: In the liver, efficacy of cryosurgical ablation of tumors located near the retrohepatic vena cava is impaired by the heat-sink effect. This could be overcome by total vascular exclusion (TVE) of the liver. In this study, the effect of TVE on cryosurgical ablation of liver tissue close to the retrohepatic vena cava was investigated with regard to the extent of the cryolesion and complications arising from necrosis of the caval wall. METHODS: Of a total of 28 pigs, 14 underwent cryotherapy with TVE compared to 14 without TVE, both involving the vena cava. 7 animals in each group were subjected to one freeze cycle and 7 in each group to two freeze cycles. Temperatures in the cryolesion were monitored and cryolesions were documented sonographically. Laboratory parameters were determined pre- and postoperatively. Follow-up was 14 days. Morphology, extent of the cryolesion, damage to the vena cava and complications were assessed after autopsy. RESULTS: With TVE, freezing rates were increased and cryolesions were significantly larger than without TVE. Transmural necroses of the vena cava with complete necrosis of the intima occurred significantly more frequently after TVE. Macro- and microscopically, the damage to the caval wall was considerably more marked after cryotherapy under TVE but in all cases the continuity of the vessel wall remained intact. There were no ruptures, thrombosis, or strictures of the vena cava. CONCLUSIONS: The combination of cryotherapy and TVE increases the effectiveness of cryoablation in the liver involving the retrohepatic vena cava without any severe vascular complications occurring in the pig. 相似文献
939.
Use of a branch patch with the cystic artery in living-related liver transplantation 总被引:2,自引:0,他引:2
Di Benedetto F Lauro A Masetti M Cautero N Quintini C Dazzi A Ramacciato G Risaliti A Miller CM Pinna AD 《Clinical transplantation》2004,18(4):480-483
Technical aspects in living-related liver transplantation are still under debate: the main pitfall is the arterial reconstruction due to the small diameter and the discrepancy between stumps, with a subsequent increased risk of arterial thrombosis. The gold standard is the microsurgical technique, that reports the lowest risk of thrombosis, but it is a time consuming procedure requiring a long training. Our method of choice reconstructing hepatic artery in right lobe is the use of the cystic artery as a branch patch with the recipient hepatic artery by loop magnification, saving time and with a low incidence of hepatic artery thrombosis. 相似文献
940.
Clinical Hepatic Impairment after the Duodenal Switch 总被引:1,自引:0,他引:1
Background: Nonalcoholic steatohepatitis (NASH) is the most common histological finding in morbidly obese patients undergoing
liver biopsy. Biliopancreatic diversion has been widely used for the treatment of morbid obesity and hepatic steatosis, and
very few cases of liver impairment as a complication of this operation have been reported. Methods: During the last 9 years,
470 morbidly obese patients were operated by means of a biliopancreatic diversion with duodenal switch ( BPD-DS), and 93 of
them were performed laparoscopically. Results: 10 cases of clinical hepatic impairment occurred after the BPD-DS. The clinical
course of these patients ranged from transient subclinical alterations of liver function tests to severe cases of jaundice
and one death from liver failure. Conclusion: Randomized prospective studies with standardization of BPD-DS are needed, to
know the real incidence of hepatic impairment and the proper treatment for this condition. Careful follow-up and correction
of possible malnutrition should be addressed to avoid hepatic impairment and/or progression of liver disease. 相似文献