Hepatic perfusion changes in an experimental model of acute pancreatitis: Evaluation by perfusion CT

Purpose

It is known that acute pancreatitis may cause secondary changes in several organs. Liver is one of these involved organs. In different experimental studies hepatic damages were shown histopathologically in acute pancreatitis but there are a few studies about perfusion disorders that accompany these histopathologic changes. Perfusion CT (pCT) provides the ability to detect regional and global alterations in organ blood flow. The purpose of the study was to describe hepatic perfusion changes in experimental acute pancreatitis model with pCT.

Materials and methods

Forty Sprague-Dawley rats of both genders with average weights of 250 g were used. Rats were randomized into two groups. Twenty rats were in control group and 20 in acute pancreatitis group. pCT was performed. Perfusion maps were formed by processing the obtained images with perfusion CT software. Blood flow (BF) and blood volume (BV) values were obtained from these maps. All pancreatic and liver tissues were taken off with laparotomy and histopathologic investigation was performed. Student's t test was used for statistical analyses.

Results

In pCT we found statistically significant increase in blood volume in both lobes of liver and in blood flow in right lobe of the liver (p < 0.01). Although blood flow in left lobe of the liver increased, it did not reach statistical significance.

Conclusion

The quantitative analysis of liver parenchyma with pCT showed that acute pancreatitis causes a significant perfusion changes in the hepatic tissue. Systemic mediators seem to be effective as well as local inflammatory changes in perfusion changes.     

Uncertainty analysis of in-situ gamma spectrometry measurements of air cleaning filter cartridges and 200 L drums by a HPGe detector

This work deals with most significant sources of uncertainty in determination of radionuclides massic activity in 200 L drums with radioactive waste (RAW) from decommissioning of nuclear power plant (NPP) A1 and operational air cleaning filters coming from different parts of NPP's ventilation system. It turned out that the most significant source of uncertainty is determination of photo peak detection efficiency, in particular measurement geometry. The detection efficiency of HPGe detector has been determined by calculation using ISOCS software (In Situ Object Counting System) and detector characteristics delivered by the manufacturer (LABSOCS). The detector efficiency is influenced by various factors like measurement geometry, deviation from standard geometry, environmental characteristics, sample properties (density, material composition), used collimator etc. Mentioned factors and their contributions to the uncertainty of detection efficiency and thus to the total uncertainty of massic activity determination have been individually evaluated in the paper. The main part of the work consists of evaluation of maximum uncertainty factor due to presence of hypothetical point source in measurement volume for both types of measurement geometry.     

Schwannoma of the brachial plexus: cross-sectional imaging diagnosis using CT,sonography, and MR imaging

Primary brachial plexus tumors are rare, usually benign, and in general have a good prognosis after surgical excision. We present a case of a schwannoma in which sonography enabled the correct diagnosis of a probably benign brachial plexus tumor. Key to the diagnosis was the demonstration of a smooth-bordered, longish, and well-defined nodule along a brachial plexus nerve root. Cross-sectional imaging modalities that provide a high degree of soft tissue contrast and spatial resolution, such as sonography and MR imaging, were suitable methods to establish the correct preoperative diagnosis. Findings at CT, sonography, MR imaging, and surgery are discussed.     

电影相位对比与屏气二维相位对比MRI对肝硬化门静脉血流的对照研究

目的探讨MRI电影法相位对比（Cine PC）与屏气二维相位对比（2D PC）在肝硬化患者和正常志愿者门静脉血流测量中的诊断价值。资料与方法对照组为82名志愿者,男45名,女37名,平均年龄26.65岁;肝硬化组24例,男14例,女10例,平均年龄42.00岁。空腹状态下采用CinePC技术对门静脉血流定量测量,同期采用2DPC技术3种不同屏气状态（正常吸气屏气,呼气屏气,平静呼吸屏气）与其进行比较。结果肝硬化患者门静脉血流速度较对照组略减低,除2D PC平静呼吸法,余方法两组差异均无统计学意义,肝硬化组门静脉血流量与对照组比较明显增大（P〈0.01）,但2DPC吸气屏气技术两者差异无统计学意义。采用相关性分析对屏气2DPC（不同呼吸状态）与Cine PC MRI方法定量门静脉血流速度、血流量,显示两种技术相关性很好（r〉0.8;P〈0.01）,但在对照组行相关性分析,仅呼气后屏气2D PC与Cine PC显示中度相关（r〉0.5;P〈0.01）,吸气后屏气与CinePC相关性较差（r〈0.4）。结论MRI Cine PC在正常呼吸情况下对门静脉血流行定量测量,接近人体生理状态,适合门静脉血流测量;正常呼吸状态屏气对肝硬化患者门静脉血流影响较正常人小,在肝硬化血流测量中,MRI Cine PC与屏气2DPCMRI法显示很好相关性。屏气2DPCMRI技术提供了一种简便、实用、相对准确的肝硬化门静脉血流测量方法。     

Laparoscopic management of common bile duct stones

Background While laparoscopic cholecystectomy is widely accepted for therapy of cholecystolithiasis, controversy still exists concerning the management of common bile duct stones. Besides preoperative endoscopic papillotomy followed by laparoscopic cholecystectomy and open common bile duct surgery, management of common bile duct stones can be conducted by laparoscopy, if respective experience is available.Method During laparoscopic cholecystectomy a cholangiography via the cystic duct is routinely performed. If bile duct stones are detected they are retrieved via the cystic duct or via incision of the common bile duct by insertion of a Fogarty catheter or Dormia basket. Exclusion criteria against simultaneous laparoscopic management include suspicion of malignancy, severe pancreatitis, or cholangitis.Results From November 1991 to March 2002, 200 patients primarily underwent laparoscopic therapy of bile duct stones. Retrieval was performed via cystic duct and common bile duct incision in 115 and 85 cases, respectively. Complete removal was achieved in 91%; complication rate and mortality was 7% and 0.5%, respectively. During the same period primary endoscopic papillotomy was necessary in 40 patients because of the above contraindications.Conclusions When correct indications and surgical expertise are observed, simultaneous laparoscopic management of common bile duct stones represents a safe and minimally invasive alternative to a two-procedure approach.     

Minimally invasive management of dysontogenetic hepatic cysts

Background Liver cysts occur with a prevalence of 4%–7% in the general population. Laparoscopic surgery is effective for solitary cysts and in selected patients with polycystic liver disease (PLD). We present our experience in the laparoscopic management of dysontogenetic cysts.Patients and methods Between 1994 and 2002, 36 patients were referred to our centre for the management of dysontogenetic cystic liver disease. Management was laparoscopic in 16 cases. Indications were solitary giant cysts (n=9) and PLD (n=7).Results Laparoscopic procedures were completed in 15 patients. Mean operating time was 90 min. There were no deaths. In one case there was an intraoperative complication: bleeding from a superficial hepatic vein necessitated conversion to an open procedure. There were two postoperative complications: one patient with biliary leakage, which was managed conservatively, and one patient with a pneumothorax caused by the cava catheter installed for anaesthesia. Median follow-up was 36 months. There was no symptomatic recurrence.Conclusion Laparoscopy can be recommended as the procedure of choice for symptomatic solitary giant cysts and PLD Gigot type I.     

The nutrient artery canal of the femur: a radiological study in patients with primary total hip replacement

Objective Plain antero-posterior and lateral radiographs of the femur often show radiolucent lines, which may reflect the canal of a nutrient artery. In patients who have undergone total hip replacement these radiolucent lines must be differentiated from fractures caused by bursting of the shaft during the procedure.Design and patients In a retrospective radiological study 129 extremities of 95 patients with cementless primary hip prostheses were examined for radiolucent lines. Pre- and postoperative antero-posterior and lateral radiographs were analyzed.Results In 34 of 129 extremities (26.4%) radiolucent lines compatible with a nutrient artery canal were detected, 14 of which (10.9% overall) were seen on lateral radiographs. In 11 of 129 extremities (8.5%) a nutrient artery canal was detected only on the antero-posterior views, while in 9 of 129 extremities (7.0%) it was well defined in both projections. One patient (0.8%) presented with a fracture postoperatively, which was radiologically distinct from a nutrient artery canal. The distance between the tip of the greater trochanter and the proximal end of the nutrient artery canal was 170±25 mm; the canal length was 27±9 mm.Conclusion Nutrient artery canals are often seen radiologically on pre- and postoperative radiographs down to the mid-shaft level and should be routinely recorded.     

颈髓血流障碍与脊髓型颈椎病发病机制的实验研究

目的观察脊髓前动脉阻断对颈髓血供、功能的影响及其病理学变化,研究脊髓型颈椎病的发病机制。方法以家兔为实验模型,阻断C2段脊髓前动脉,在术后6h、24h、72h采用改良Tarlov法对动物行为学评级以及检测运动诱发电位的变化,应用激光多普勒血流测定仪测定颈髓血流灌注量,并观察兔颈髓组织细胞形态学、相关免疫组化的变化。结果术后各时相点神经功能减退,血流量下降明显,神经元骨架结构紊乱,细胞器破坏,出现急性缺血性改变。结论脊髓前动脉血流障碍可导致颈髓缺血性病变,引起脊髓的梗死,是脊髓型颈椎病发生不可忽视的重要因素,对其治疗应注意改善局部血液循环。     

Promising role of preoperative neutrophil-to-lymphocyte ratio in patients treated with radical nephroureterectomy

Objective

Several retrospective studies with small cohorts reported neutrophil-to-lymphocyte ratio (NLR) as a prognostic marker in upper tract urothelial carcinoma (UTUC) following radical nephroureterectomy (RNU). We aimed at validating the predictive and prognostic role of NLR in a large multi-institutional cohort.

Methods

Preoperative NLR was assessed in a multi-institutional cohort of 2477 patients with UTUC treated with RNU. Altered NLR was defined by a ratio >2.7. Logistic regression analyses were performed to assess the association between NLR and lymph node metastasis, muscle-invasive and non-organ-confined disease. The association of altered NLR with recurrence-free survival (RFS) and cancer-specific survival (CSS) was evaluated using Cox proportional hazards regression models.

Results

Altered NLR was observed in 1428 (62.8 %) patients and associated with more advanced pathological tumor stage, lymph node metastasis, lymphovascular invasion, tumor necrosis and sessile tumor architecture. In a preoperative model that included age, gender, tumor location and architecture, NLR was an independent predictive factor for the presence of lymph node metastasis, muscle-invasive and non-organ-confined disease (p < 0.001). Within a median follow-up of 40 months (IQR 20–76 months), 548 (24.1 %) patients experienced disease recurrence and 453 patients (19.9 %) died from their cancer. Compared to patients with normal NLR, those with altered NLR had worse RFS (0.003) and CSS (p = 0.002). In multivariable analyses that adjusted for the effects of standard clinicopathologic features, altered NLR did not retain an independent value. In the subgroup of patients treated with lymphadenectomy in addition to RNU, NLR was independently associated with CSS (p = 0.03).

Conclusion

In UTUC, preoperative NLR is associated with adverse clinicopathologic features and independently predicts features of biologically and clinically aggressive UTUC such as lymph node metastasis, muscle-invasive or non-organ-confined status. NLR may help better risk stratify patients with regard to lymphadenectomy and conservative therapy.