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11.
Background and study aims  Stent migration occurs in about 5–10% of patients undergoing biliary stenting. The aim of this study was to analyze the risk factors for stent migration in patients with benign and malignant strictures. Patients and methods  We retrospectively analyzed records of 524 biliary plastic stent placement procedures. Details noted included the cause and localization of stricture, characteristics and number of stents, direction of stent migration, presentation of patient with migrated stent, and the methods used for retrieval of migrated stents. Results  Two hundred and four (38.9%) of the procedures were performed for benign biliary strictures (BBS) and 320 (61.1%) for malignant biliary strictures (MBS). Thirty-four patients had 45 migrated biliary stents. The rate of migration was 8.58% (proximal 4.58% and distal 4.00%). Migration frequency was higher in BBS compared with MBS (13.7% versus 5.3%, p = 0.001). In BBS, the rate of stent migration was higher in cases with one (19.3%) and two stents (20.9%) when compared with cases with multiple stents (2.7%) (p = 0.001; p = 0.001, respectively). Migration occurred more frequently (10.9%) in cases with two stents when compared both to cases with one stent (3.0%) and those with multiple stents (0%) in MBS (p = 0.008; p = 0.020, respectively). In BBS, short stents migrated more frequently proximally (77%) and long stents more frequently distally (73%) (p = 0.008). In BBS, migration in cases with proximal stricture occurred more frequently distally (76.9%), while in those with distal stricture, migration was more frequently proximal (73.3%) (p = 0.008). All of the proximally migrated stents could be successfully retrieved endoscopically. Conclusions  The risk of stent migration is higher in BBS compared with in MBS. The cases with multiple stents had significantly lower stent migration. In BBS, long stent, proximal and postcholecystectomy strictures were associated with distal migration, while short stent, distal and non-postcholecystectomy strictures were associated with proximal migration.  相似文献   
12.
The present study evaluated99mTc(V) DMSA as an agent for the visualization of inflammatory lesions in comparison to99mTc(HI) DMSA and99mTc-HIG. All three radiopharmaceuticals were prepared with commercial kits.99mTc(V) DMSA was prepared at neutral pH by the addition of first bicarbonate and then pertechnetate to the kit contents. The labeling efficiency was 99% as determined by ITLC. Abscesses were induced by i.m. injection of 50 μl turpentine into the right thighs of 36 Swiss albino mice. Six days later 3.7 MBq of each radiopharmaceutical was i.v. administered to 12 mice. The mice were sacrificed at 1,3,6 and 24 h later. Scintigrams were obtained with a gamma camera. The abscesses were better visualized on scintigrams with99mTc(V) DMSA compared to99mTc(III) DMSA, starting at 1 h. The animals were dissected and the organs were removed, weighed and the radioactivity determined with a gamma counter. The abscess to other tissue ratios were higher with99mTc(V) DMSA than the other radiopharmaceuticals. The max. abscess/muscle ratios were 9.46 ± 3.20 (24 h), 4.19 ± 1.39 (6 h) and 5.98 ± 1.17 (24 h) and max. abscess/blood ratios were 6.22 ± 1.41, 4.09 ± 0.84 and 0.914 ± 0.351 all at 24 h for99mTc(V) DMSA,99mTc(III) DMSA and99mTc-HIG, respectively. Experimental arthritis was produced in 6 New Zealand white rabbits by intra-articular injection of ovalbumin. Four days later 37 MBq of99mTc(V) DMSA and99mTc-HIG were each i.v. administered to 3 rabbits. Scintigrams obtained at 1, 3, 6, and 24 h clearly demonstrated arthritic joints. ROFs over arthritic joints were compared to contralateral normal joints (A/C). The max. A/C ratios were 2.10 ± 0.31 (3 h) and 2.92 ± 0.99 (24 h) for99mTc(V) DMSA and99mTc-HIG, respectively. Our results indicated the feasibility of imaging inflammatory lesions with99mTc(V) DMSA.  相似文献   
13.
Thumb hypoplasia represents a major disability requiring sophisticated reconstructive procedures. One of the basic criteria of the pollicization to construct a functional thumb is scar free web reconstruction. In this article, a technique to avoid excessive scarring in the first web space reconstruction by filleting out the hypoplasic thumb combining with a triangular flap is presented. A 5-year-old girl was presented. She had a Back-Gramcko type IV thumb hypoplasia. A triangular flap was planned on radial border of the long finger. Floating thumb was filleted out with preservation of the neurovascular bundle and transferred to the first web space while cooperating with triangular flap. Patient was followed up for 18 months. No early or late major complication was seen. Flap healed without any necrosis. The ratio of active motion in pollicized finger was measured 60% after cerebral reorientation. A satisfactory grip and pinch were seen in pollicized finger. Patient as well as her parents was satisfied with the results. Filleting out the floating thumb and combining with a triangular flap harvested by a V-Y flap design is a good option to avoid excessive scarring in reconstruction of the first web space in pollicization. It is strongly recommended that floating thumb should be preserved for future pollicization, and any attempt to amputate it in early years of life should be postponed till the time of definitive surgery.  相似文献   
14.
Cardiovascular abnormalities are observed in most children with end-stage renal disease (ESRD). The aim of this study was evaluation of left-ventricular (LV) myocardial performance using tissue-Doppler imaging (TDI) in patients with ESRD. Twenty-five patients with ESRD and 25 healthy gender- and age-matched control subjects were assessed with conventional M-mode echocardiography, pulsed-wave Doppler (PWD), and TDI. Myocardial Performance Index (MPI) and LV mass index (LVMI) were calculated. MPI and conventional echo-Doppler indices were compared in the ESRD and control groups. Significant differences were present in the mean systolic and diastolic blood pressure (BP) between children with ESRD and healthy children (p = 0.007 and p < 0.001, respectively). The mean LVMI was significantly greater in the patient group (p < 0.001). The tissue-Doppler MPI of patients was significantly higher than that in healthy children (p < 0.001). LVMI was significantly correlated with systolic and diastolic BP. MPI obtained by TDI was significantly correlated with LVMI. Our study confirms that LV dysfunction is present in patients with ESRD and hypertension is an important risk factor.  相似文献   
15.
BACKGROUND CONTEXT: Intraradicular lumbar disc herniation is rare, having been reported to date in only three postoperative patients. The diagnosis is typically made intraoperatively. PURPOSE: To report a fourth case of intraradicular disc herniation, to emphasize its radiological characteristics and operative findings. STUDY DESIGN: Case report. PATIENT SAMPLE: A 41-year-old female. METHODS: Retrospective case review. RESULTS: The patient underwent a second operation and intraradicular disc fragment was removed. She was completely well at her 9-month check up. CONCLUSIONS: The diagnosis, mechanism, and surgical treatment of intraradicular lumbar disc herniation are reviewed. The round shape of the sequestrated fragment, as seen on magnetic resonance imaging, may help to establish the correct diagnosis.  相似文献   
16.
As a potent vasoconstrictor, epinephrine is used ubiquitously in plastic surgery. It is typically delivered subcutaneously in very low concentrations over a brief time interval. We are aware of no reports describing the long-term release of epinephrine as an independent agent to the soft tissues for the purpose of causing prolonged local vasoconstriction. This study was designed to address two goals: first, to investigate the effect of long-term local release of epinephrine from a drug delivery system on rat abdominal skin vasculature; secondly, to evaluate the pharmacological properties of this drug delivery system (DDS). Thirty male Sprague-Dawley rats, weighing 300-400 g, were included in the study. Animals were subdivided into two groups of 15 each. Group A (control group) and Group B (experimental group) were treated with saline and epinephrine-loaded microspheres (msps), respectively. The manufacturing process and formulation studies of the DDS are described. In vivo assays revealed a 7-day sustained release of epinephrine. After 7 days, neither residual nor supraphysiologic release of epinephrine was shown with high-performance liquid chromatography (HPLC). Histological studies with hematoxylin-eosin and periodic acid Schiff revealed a statistically significant increase in number of vessels as well as their diameter and wall thickness (P <0.05). Epinephrine release via this msp/DDS predictably induces local vasoconstriction over a time sequence known to be optimally associated with hypoxia and promotion of vascular augmentation. This model can be valuable in sustaining hemostasis during long-lasting (more than a few hours) surgical procedures by its long-acting vasoconstructive effect. The system's ability to intentionally cause vascular augmentation also bodes great potential in flap and graft surgery.  相似文献   
17.
Heterotopic pancreas is a relatively common variant of foregut embryologic dystopia that can be described as pancreatic tissue found outside the normal anatomic location, being independent from vascular supply of normal pancreas. Having all features of pancreatic tissue except for the major duct structures, this ectopic tissue may be clinically recognized when pathologic changes take place. Inflammation, hemorrhagic or obstructive states, and eventually malignancy-related problems may become a diagnostic challenge for clinician and finally lead to consequences of misdiagnosis. In this article we will discuss a case of heterotopic pancreatic tissue located in gastric cardia, which was diagnosed preoperatively as gastrointestinal stromal tumor.Key words: Ectopic pancreas, Pseudocyst, Gastrointestinal stromal tumor, MisdiagnosisHeterotopic (ectopic) pancreas is defined as the presence of pancreatic tissue in an aberrant site that is not anatomically and vascularly connected to the pancreas proper.1,2 Ectopic pancreatic tissue is most commonly found in the duodenum (particularly the second portion), ampulla, stomach (prepyloric antrum), and upper jejunum; it can also occur in the liver, biliary tract, Meckel''s diverticulum, and several other sites such as large bowel, spleen, omentum, mediastinum, lung, thyroid, and even brain.16 The heterotopic pancreatic tissue is usually located in the submucosa and/or the muscularis or subserosa.1,2,4Practically any pancreatic pathology can also occur in the heterotopic pancreatic tissue including acute pancreatitis and neoplastic transformation.1,4,7,8 Episodes of acute pancreatitis may cause local inflammation and typical pancreatitis-related complications in the host organ. The ectopic pancreatic tissue can lead to ulceration and bleeding in the cases located beneath a mucosa. Being a mass-forming lesion, it may also result in luminal obstruction (particularly in the prepyloric antrum).1,4Although it is a relatively common congenital anomaly (0.5% to 13% in autopsy series), in most cases heterotopic pancreas remains clinically silent and is found incidentally during surgery or an endoscopic and/or radiological investigation.1,9 Heterotopic pancreas may be confused with other solid tumors of the host organ.Heterotopic pancreas in the stomach is usually located in the prepyloric area.10 We report here an unusual case of heterotopic pancreas with a pseudocyst formation in the gastric cardia mimicking gastrointestinal stromal tumor.  相似文献   
18.
Neurosurgical Review - “Benign” metastatic leiomyomas (BML) are indolently growing metastatic tumors which mostly associate with uterine leiomyomas in women in reproductive ages. The...  相似文献   
19.
The objective of this investigation was to evaluate the reliability of classification systems by determining inter- and intraobserver agreement in displaced distal radius fractures. Radiographs of 32 patients (21 men and 11 women with a mean age of 41.6 years) who presented with a displaced distal radius fracture were classified by 9 orthopedic surgeons (5-25 years experience) using 5 different classification systems (Fernandez, AO, Frykman, Melone, and Universal Classification systems) twice with 20-day intervals. The results were processed with kappa statistics and used in assessment of inter- and intraobserver agreement of the classification systems. When classification systems were compared, the highest kappa coefficient in intraobserver agreement was determined in Universal classification (0.621). Fernandez (0.474), AO (0.309), Frykman (0.305), and Melone classification systems (0.262) followed the Universal system respectively. Kappa statistical results were evaluated using the Landis Koch score system for the assessment of interobserver agreement. According to the Landis Koch score system, the results were insufficient in all classification systems. Fernandez classification system had the highest interobserver agreement (0.235) and Melone classification system had the lowest interobserver agreement (0.056). According to the results of our study, the systems used to classify the displaced distal radial fractures are insufficient. A new classification system that ensures the 3-dimensional assessment of the fracture is more user-friendly and a high inter- and intraobserver agreement is necessary.  相似文献   
20.
OBJECTIVE: The aim of this study is to investigate dose-dependent effect of the topical application of methotrexate (MTX) in rats on the normal nasal mucosa, liver tissue, liver enzymes, and hemoglobin levels. STUDY DESIGN: Preclinical animal study. SETTING: Twenty male adult wistar albino rats were randomly divided into 4 groups (n=5). A single puff of MTX (2.5 microg) was applied to both nasal cavities 2 times a day. The animals were given MTX 1 day a week in group 1, 3 days a week in group 2, and 5 days a week in group 3. Control group animals were given 1 puff of physiologic saline to both nasal cavities 5 days a week and 2 times a day. After 28 days, liver biopsies, blood samples, and 5 nasal mucosal biopsies were taken. Histological examination was made with respect to certain parameters semiquantitatively (grade 0-3). The aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and hemoglobin counts were studied from blood samples. RESULTS: There are no statistically significant differences with respect to histopathological parameters between the control group and the groups 1-3 (P>0.05). Histopathological examination of liver tissue did not reveal any evident difference between the control and study groups. Mean AST and ALT as liver function tests and hemoglobin counts were within normal limits. Topical application of MTX at these doses has no toxic effect on the nasal mucosa, the liver tissue, AST and ALT levels, and hemoglobin level. CONCLUSIONS: These results have been encouraging to investigate use of the topical application of MTX in nasal manifestation of autoimmune disease or addition of the topical application of MTX to the steroid treatment in cases with massive nasal polyposis resistant to steroids and prone to recurrence.  相似文献   
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