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81.

Purpose

The most common pituitary tumors are adenomas, which however may be mimicked by other tumors that can show a very similar appearance in plain MRI. The aim of our study was to evaluate the usefulness of perfusion weighted MR imaging (PWI), including signal-intensity curves analysis in the differential diagnosis of sellar/parasellar tumors.

Methods

Forty-one patients with sellar/parasellar tumors (23 macroadenomas, 10 meningiomas, 5 craniopharyngiomas, 1 intrasellar hemangioblastoma, 1 intrasellar prostate cancer metastasis, 1 suprasellar glioma), underwent plain MRI followed by PWI using a 1.5T unit. In each tumor, the mean and maximum values of relative cerebral blood volume (rCBV), as well as the relative peak height (rPH) and the relative percentage of signal intensity recovery (rPSR) were calculated.

Results

The high perfusion tumors were: macroadenomas, meningiomas, squamous-papillary type of craniopharyngiomas, hemangioblastoma, glioma and metastasis. The low perfusion neoplasms included adamantinomatous type of craniopharyngiomas. By comparing adenomas and meningiomas, we found statistically significant differences in the mean and maximum rCBV values (p = 0.026 and p = 0.019, respectively), but not in rPH and rPSR. The maximum rCBV values >7.14 and the mean rCBV values >5.74 with the typical perfusion curve were very suggestive of the diagnosis of meningioma. There were differences between adenomas and other high perfusion tumors in rPH and rPSR values.

Conclusions

PWI can provide additional information helpful in differential diagnosis of sellar/parasellar tumors. In our opinion PWI, as an easy to perform and fast technique should be incorporated into the MR protocol of all intracranial neoplasms including sellar/parasellar tumors.  相似文献   
82.

Objective

To evaluate DW MR tumour volumetry and post-CRT ADC in rectal cancer as predicting factors of CR using high b values to eliminate perfusion effects.

Methods

One hundred rectal cancer patients who underwent 1.5-T rectal MR and DW imaging using three b factors (0, 150, and 1,000 s/mm2) were enrolled. The tumour volumes of T2-weighted MR and DW images and pre- and post-CRT ADC150–1000 were measured. The diagnostic accuracy of post-CRT ADC, T2-weighted MR, and DW tumour volumetry was compared using ROC analysis.

Results

DW MR tumour volumetry was superior to T2-weighted MR volumetry comparing the CR and non-CR groups (P?<?0.001). Post-CRT ADC showed a significant difference between the CR and non-CR groups (P?=?0.001). The accuracy of DW tumour volumetry (Az?=?0.910) was superior to that of T2-weighed MR tumour volumetry (Az?=?0.792) and post-CRT ADC (Az?=?0.705) in determining CR (P?=?0.015). Using a cutoff value for the tumour volume reduction rate of more than 86.8 % on DW MR images, the sensitivity and specificity for predicting CR were 91.4 % and 80 %, respectively.

Conclusion

DW MR tumour volumetry after CRT showed significant superiority in predicting CR compared with T2-weighted MR images and post-CRT ADC.

Key Points

? Diffusion-weighted MR (DWMR) imaging offers new information about rectal cancer. ? DWMR helps to predict complete remission after chemoradiotherapy in patients with advanced rectal cancer. ? DWMR provides more accurate diagnostic information than T2-weighted MRI. ? Apparent diffusion coefficients can predict CR, but they have certain clinical limitations.  相似文献   
83.
Background. It has been suggested that the sympathetic nervous system might play an important role in the development of coronary artery spasm. However, no cardiac imaging modality has been able to demonstrate abnormal sympathetic innervation in patients with coronary artery spasm. The purpose of this study was to assess the presence and location of abnormal sympathetic innervation using iodine 123-metaiodobenzylguanidine (123I-MIBG) single photon emission computed tomography (SPECT) and to evaluate the clinical efficacy of 123I-MIBG SPECT as a noninvasive screening test in patients with coronary artery spasm.Methods and Results. Coronary arteriography and a provocative test with intravenous administration of ergonovine maleate were performed in 26 patients (20 men, 6 women, mean age 48.2 ± 12.0 years, range 20 to 67 years) who were suspected of having a coronary artery spasm. The subjects were divided into 2 groups: group 1 (n = 18) comprised subjects with a positive provocative test result, and group 2 (n = 8) comprised subjects with negative provocative test results. Ten healthy subjects served as controls. No abnormal MIBG uptake was observed in the control subjects. Abnormal sympathetic nervous innervation using 123I-MIBG SPECT was observed either as a reduced uptake or a defective pattern in the perfused areas in 13 of the 18 regions supplied by vessels of ergonovine-induced vasospasm. Normal sympathetic innervation, as evidenced by normal 123I-MIBG uptake, was noted in all of the 60 segments of normal vessel territories. Reduced uptake of 123I-MIBG was not detected in the perfused areas of 5 vasospasm-induced vessels (perfusion territory of left anterior descending coronary artery [LAD] and the right coronary artery [RCA] in 2 and 3 patients, respectively). The sensitivity and specificity of 123I-MIBG for detection of coronary artery spasm were 72.2% (95% confidence interval [CI] 55 % to 89 %) and 100 %, respectively. The positive predictive and negative predictive values were 100% and 92.3% (95% CI 91% to 93%), respectively.Conclusion. 123I-MIBG SPECT is a feasible method to evaluate noninvasively and localize the territories of coronary arteries with spasm. Invasive diagnostic coronary arteriography with ergonovine provocation test may be unnecessary for diagnosis of coronary artery spasm in patients with typical resting pain, negative exercise test or normal thallium perfusion scan results, but showing abnormalities in 123I-MIBG SPECT.  相似文献   
84.
Background  It has been suggested that the sympathetic nervous system might play an important role in the development of coronary artery spasm. However, no cardiac imaging modality has been able to demonstrate abnormal sympathetic innervation in patients with coronary artery spasm. The purpose of this study was to assess the presence and location of abnormal sympathetic innervation using iodine 123-metaiodobenzylguanidine (123I-MIBG) single photon emission computed tomography (SPECT) and to evaluate the clinical efficacy of 123I-MIBG SPECT as a noninvasive screening test in patients with coronary artery spasm. Methods and Results  Coronary arteriography and a provocative test with intravenous administration of ergonovine maleate were performed in 26 patients (20 men, 6 women, mean age 48.2±12.0 years, range 20 to 67 years) who were suspected of having a coronary artery spasm. The subjects were divided into 2 groups: group 1 (n=18) comprised subjects with negative provocative provocative test result, and group 2 (n=8) comprised subjects with negative provocative test results. Ten healthy subjects served as controls. No abnormal MIBG uptake was observed in the control subjects. Abnormal sympathetic nervous innervation using 123I-MIBG SPECT was observed either as a reduced uptake or a defective pattern in the perfused areas in 13 of the 18 regions supplied by vessels of ergonovine-induced vasospasm. Normal sympathetic innervation, as evidenced by normal 123I-MIBG uptake, was noted in all of the 60 segments of normal vessel territories. Reduced uptake of 123I-MIBG was not detected in the perfused areas of 5 vasospasm-induced vessels (perfusion territory of left anterior descending coronary artery [LAD] and the right coronary artery [RCA] in 2 and 3 patients, respectively). The sensitivity and specificity of 123I-MIBG for detection of coronary artery spasm were 72.2% (95% confidence interval, [CI] 55% to 89%) and 100%, respectively. The positive predictive and negative predictive values were 100% and 92.3% (95% CI 91% to 93%), respectively. Conclusion   123I-MIBG SPECT is a feasible method to evaluate noninvasively and localize the territories of coronary arteries with spasm. Invasive diagnostic coronary arteriography with ergonovine provocation test may be unnecessary for diagnosis of coronary artery spasm in patients with typical resting pain, negative exercise test or normal thallium perfusion scan results, but showing abnormalities in 123I-MIBG SPECT. Presented in part at the European Association of Nuclear Medicine Congress, September 1996, Copenhagen, Denmark.  相似文献   
85.
Ha Y  Lee JE  Kim KN  Cho YE  Yoon DH 《Acta neurochirurgica》2003,145(6):483-487
  相似文献   
86.
目的探讨西地那非对高原移居青年血流动力学的影响。方法把进驻海拔3700m半年的20名青年随机分为两组,每组10人,一组为服药组,另一组为对照组。两组在服药1h后分别用XG-Ⅲ型血液循环功能自动测试仪检测血流动力学。结果服药组较对照组P、TPR、ALT、η、PAWP、CCP降低,差异有统计学意义(P(0.05);SV、mAP、BK、BV增高,差异有统计学意义(P(0.05)。结论服用西地那非对高原移居青年血流动力学有明显的改善作用。  相似文献   
87.
富氧水对高原移居半年青年运动后肾功的影响   总被引:1,自引:1,他引:1  
目的探讨在高原口服富氧水对移居半年青年运动后肾功的影响。方法在海拔3700 m选择10名已习服半年的健康男性青年,采用口服富氧水前(对照组)后(实验组)的自身对比运动负荷双盲实验。实验组口服富氧水,对照组口服5%葡萄糖注射液,每次500 ml,2次/d,连续服用3 d。运动结束后检测血中肌酐(CRE)、尿素氮(BUN)及尿酸(UA)在口服富氧水前后的变化。结果实验组较对照组CRE、BUN和UA均降低,有显著性差异(P<0.01)。结论富氧水可改善低氧环境下肾组织的损害,对高原低氧环境下的肾脏有保护作用。  相似文献   
88.
BACKGROUND: Laparoscopic approaches have become increasingly used in selected patients with either colorectal or liver cancer. However, the feasibility of laparoscopic-assisted combined colon and liver resection in primary colorectal cancer with synchronous liver metastases remains unknown. The aim of the present study was to determine the feasibility of laparoscopic-assisted combined colon and liver resection for primary colorectal cancer with synchronous liver metastases. METHODS: Laparoscopic surgery involving intestinal anastomosis was performed for primary colorectal cancer. The liver was then mobilized with the assistance of a hand inserted through the upper midline incision. For minor resections, the parenchymal transection was performed laparoscopically. For major resection involving a hilar dissection, transection was performed according to the standard open techniques under direct vision through the incision. Resected specimens were retrieved directly through the midline incision. RESULTS: Ten patients with primary colorectal cancer and synchronous liver metastases underwent the above procedure between September 2006 and April 2007. Surgical procedures for colorectal cancer included 5 low anterior resections, 3 anterior resections, 1 right hemicolectomy, and 1 subtotal colectomy. Combined hepatic surgery included 6 major hepatectomies, 3 segmentectomies, and 1 tumorectomy. All procedures were successful, with no conversions to open surgery required. The median operation time was 439 min (range: 210-690 min), and the median estimated blood loss was 350 ml (range: 300-1,200 ml). There was no surgical mortality or major morbidity, except in one patient in whom postoperative bleeding at the site of para-aortic node dissection was promptly controlled. CONCLUSIONS: Laparoscopic-assisted combined colon and liver resection is a feasible and safe procedure for the treatment of primary colorectal cancer with synchronous liver metastases.  相似文献   
89.
We describe a new and effective arthroscopic physeal sparing repair of the tibial eminence avulsion fracture using all an inside repair technique. The treatment of ACL avulsion is controversial, especially in skeletally immature patients, with concerns about physeal damage, and a more reliable way of fixation is still being pursued for small or comminuted fragments. Screw fixation and suture cerclage has some limitations, especially in the small fragment or skeletally immature patients. We fixed avulsion fragment using all inside repair between the distal portion of the ACL and transverse ligament and periosteum. A crescent suture hook loaded with NO. 0 PDS is introduced and the suture hook pierces the transverse intermeniscal ligament and periosteum. The half length of the PDS is now advanced out through the hook and the end is brought out to the anterolateral portal. With the suture hook located intra-articularly and loaded with half the length of the original PDS, the suture hook repierces the transverse intermeniscal ligament at 5 mm on the side and the remaining half length of PDS is now advanced out through the hook and the end is brought out to the anterolateral portal. After that procedure, the suture hook loaded with NO. 0 absorbable Maxon is introduced through the anteromedial portal for the role of shuttle relay. The suture hook pierces the ACL just above the superior border of the avulsion fragment, the Maxon is now advanced out through the hook and the end is brought out to the anterolateral portal. Subsequently, the suture hook is removed and a suture retriever is introduced through the anterolateral portal. PDS and Maxon are held together and retrieved out of the anterolateral portal by the suture retriever at the same time. Our technique has advantages in small comminuted fractures and skeletally immature patients.  相似文献   
90.
BACKGROUND: Epoxyeicosatrienoic acids (EETs) are endothelium-derived hyperpolarizing factors that contribute renal protective actions. The aim of this study was to identify the association between genetic variations in soluble epoxide hydrolase (EPHX2, EET-metabolizing enzyme) and kidney allograft dysfunction. MATERIALS AND METHODS: Data from 204 kidney transplant donor-recipient pairs were examined for polymorphisms of exon 8 (R287Q, rs751141 G/A) and 3' untranslated region (3' UTR, rs1042032 A/G) of the EPHX2 gene and correlated with clinical data. RESULTS: The mean duration of follow-up for recipients was 58 +/- 45.3 months who were 39 +/- 11.8 years old at the time of operation and displayed estimated glomerular filtration rate (eGFR) of 68 +/- 16.5 mL/min/1.73 m2 at 1 month after transplantation. AA, AG, and GG genotype frequencies in 3' UTR were 28%, 55%, and 16%, respectively. Twenty-one recipients experienced allograft dysfunction with eGFR <30 mL/min/1.73 m2; 10 had AA genotype of rs1042032 polymorphism (chi-square test; A/A vs A/G+G/G; P = .04). Recipients without rs1042032 polymorphism variant allele showed a significant risk for allograft dysfunction (A/A vs A/G+G/G; P = .04; odds ratio, 2.65; 95% confidence interval [CI], 1.03-6.81). Multivariate analysis of the characteristics of patients using a Cox proportional hazard model showed that the AA genotype of rs1042032 polymorphism was predictive of allograft dysfunction (Hazard Ratio = 3.26; P = .04; 95% CI, 1.08-9.59). CONCLUSION: The present study suggested that the presence of the rs1042032 variant allele in EPHX2 was associated with a protective role for allograft function.  相似文献   
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