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991.
Direct transoral approach to C2 for percutaneous vertebroplasty   总被引:8,自引:0,他引:8  
Percutaneous vertebroplasty was performed via a transoral route in a 70-year-old woman with a C2 metastasis of thyroid origin involving anterior vertebral elements. Complete pain relief was obtained after an uncomplicated minimally invasive procedure. This preliminary experience demonstrates that a transoral approach under fluoroscopic control can provide safe access to the upper cervical spine at C2 level.  相似文献   
992.
OBJECTIVE: Endoscopic adrenalectomy represents the "New Golden Standard" in the surgical treatment of benign adrenal lesions up to 6 cm. Open adrenalectomy is recommended for patients with suspected malignant disease and tumors larger than 6 cm. METHODS AND MATERIAL: The surgical technique of trans- and retroperitoneal adrenalectomy is described. Reviewing literature the importance of the endoscopic approach and its role in the surgical treatment of adrenal lesions is analyzed. RESULTS: As in open adrenalectomy different endoscopic approaches to the adrenals were developed: adrenal tumors can be removed endoscopically using a transperitoneal (patient in a supine or lateral decubitus position) or extraperitoneal route (patient in a lateral decubitus or prone position). Reviewing literature the endoscopic transperitoneal adrenalectomy is documented in 1425 patients. 4.6% (66 patients) had to be converted to an open procedure. Five hundred and forty-four tumors were removed by an extraperitoneal access. The conversion rate was 4.4% (24 patients). CONCLUSION: The basis of excellent results are careful patient selection, evaluation and preoperative preparation in a center with experience in the open techniques and at least 20 endoscopic adrenalectomies per year.  相似文献   
993.
PURPOSE: To evaluate the feasibility and efficacy of the local application of a replication-defective adenovirus construct for the expression of the antiinflammatory protein I kappa B alpha, inhibitor of nuclear factor kappa B (NF-kappa B), to reduce neointimal formation after stent placement. MATERIALS AND METHODS: Nitinol stents were implanted in the iliac arteries of hypercholesterolemic rabbits, followed by balloon dilation (30 seconds at 6 atm). Local adenovirus-mediated transfer of I kappa B alpha (3 mL of 10(9) plaque-forming units per milliliter at 6 atm) was performed and compared with three control groups: stent alone, stent plus local delivery of phosphate-buffered saline (PBS) (3 mL at 6 atm), and stent plus local delivery of control adenovirus coding for green fluorescent protein (GFP) (3 mL of 10(9) plaque-forming units per milliliter at 6 atm). A multichannel balloon was used for local drug delivery and balloon dilation. Animals were sacrificed 1 or 4 weeks after treatment. Effective transfection was demonstrated with immunofluorescence staining. Angiographic patency and luminal diameter were evaluated at quantitative angiography. Luminal and neointimal areas were measured on surface-stained ground sections with methylmethacrylate embedding and the cutting-grinding technique. RESULTS: All vessels with stents were patent at angiography. Neointimal area was negligible in all groups 1 week after stent placement (range, 0.42-0.52 mm(2); P =.44; analysis of variance). Neointimal formation was demonstrated in all groups 4 weeks after implantation but was significantly reduced with I kappa B alpha treatment compared with treatment with stent alone (by 22%, from 2.80 mm(2) +/- 0.20 to 2.28 mm(2) +/- 0.14, P =.05), stent plus PBS (by 43%, from 3.26 mm(2) +/- 0.25 to 2.28 mm(2) +/- 0.14, P =.005), and stent plus GFP (by 53%, from 2.32 mm(2) +/- 0.19 to 1.51 mm(2) +/- 0.08, P <.005). CONCLUSION: Local adenovirus-mediated I kappa B alpha gene transfer has the potential to reduce intimal hyperplasia after stent placement.  相似文献   
994.
PURPOSE: Interventional magnetic resonance (MR)-guided transcatheter embolization could potentially limit radiation exposure and improve visualization of target organs. The feasibility of monitoring injection and distribution of embolic agents was assessed in a dynamic flow model with real-time MR imaging. MATERIALS AND METHODS: MR-compatible flow models were constructed with use of clear plastic chambers containing 170-microm polyethylene tubular filters. Gadolinium (Gd)-impregnated polyvinyl alcohol (PVA) particles (355-500 and 500-710 microm in size) and Gd-impregnated microspheres (Embospheres, 300-500 and 500-700 microm in size) were injected into the flow circuit under real-time dynamic T1-weighted fast field echo guidance at four images per second. A dynamic steady-state free precession sequence at four images per second was used to monitor the injection of unmodified Embo-Gold 700-900- microm particles. High-resolution scans were obtained before and after each particle injection. RESULTS: MR signal enhancement on the dynamic T1-weighted fast field echo sequence was visible during the injection of Gd-impregnated microspheres. Gd-impregnated PVA particles were not detected by this sequence. After injection, microsphere and PVA localization to the filter chambers was confirmed by the high-resolution scans. On the high-resolution sequences, relative MR signal enhancement of the microspheres was higher than that of the PVA particles. The Embo-Gold particles were minimally detectable on the dynamic sequence and undetectable by the high-resolution scan. After particle injection, direct inspection of the filter chamber showed trapping of all particle types and sizes. CONCLUSION: Real-time MR tracking of Gd-impregnated embolic agents is possible in vitro.  相似文献   
995.
BACKGROUND AND PURPOSE: Rotational angiography (RA) and digital subtraction angiography (DSA) together may depict more intracranial aneurysms than DSA alone. We compared the diagnostic value of 3D RA and biplanar DSA in detecting, classifying, and planning treatment for ruptured intracranial aneurysms. METHODS: A total of 53 patients with acute subarachnoid hemorrhage (Hunt and Hess grades I-V) underwent angiography with both methods. DSA was performed in two to six standard projections in every vascular territory. Three-dimensional RA datasets were evaluated by using surface-shaded display and maximum intensity projection. The usefulness of DSA images and 3D datasets in detecting aneurysms (number, configuration) and treatment planning were retrospectively analyzed in a blinded manner. RESULTS: In 42 patients, 56 aneurysms were detected, (one to five per patient; size, 0.6-20.4 mm); no aneurysm was found in 11 patients. RA revealed seven aneurysms not seen at conventional DSA. RA failed to depict one aneurysm visible only in a compression series. Delineation of the aneurysmal neck improved with RA in 71% of cases; the parent vessel and its relationship to adjacent vessels was demonstrated better with RA than with DSA in 45% and 50%, respectively. Endovascular treatment was proposed in nine patients; microsurgical therapy, in 26. In seven patients, both options were rated as being equal. Actual treatment consisted of eight endovascular procedures and 30 neurosurgical operations. Four patients died before therapy. CONCLUSION: Compared with DSA, 3D RA allows more exact depiction of anatomic details that are important in planning surgery and interventional therapy for intracranial aneurysms. RA depicted more aneurysms.  相似文献   
996.
The Department of Defense Familial Breast/Ovarian Cancer Research Project has offered genetic counseling and testing for BRCA1 and BRCA2 on a research basis to patients meeting specific diagnostic criteria, with risk for BRCA1 and BRCA2 mutations calculated based on the Couch model. In 2.5 years, 250 patients were evaluated and 101 patients met criteria requirements, including 33 who met criteria in more than one category. Ninety patients elected to undergo DNA testing. In this group of 90 patients, 14 mutations (15.5%) and 16 unclassified variants (17.7%) were identified. The most common inclusion criteria were onset of breast/ovarian cancer before age 45 years (n = 32) and onset of breast/ovarian cancer before age 45 years with strong family history (n = 21). However, when number of mutations and unclassified variants found were compared separately across all diagnostic criteria (including those of more than one capacity) using the chi 2 statistic, no significant differences were seen among the categories to suggest that one criterion was more predictive of mutations or variants than another. Couch risk values for patients with mutations showed a mean of 14% and ranged from 3.2 to 43.5% (range for all patients, 1.2-69.7%). These findings emphasize the importance of using multiple diagnostic criteria and suggest that a Couch risk value of > 3% may be useful in selecting patients for testing. The data also underscore the necessity of genetic counseling in the testing process, particularly given the large number of unclassified variants diagnosed and their uncertain status for disease predisposition.  相似文献   
997.
The reproducibility of quantitative cerebral blood flow (CBF) measurements using MRI with arterial spin labeling and acetazolamide challenge was assessed in 12 normal subjects, each undergoing the identical experimental procedure on two separate days. CBF was measured on a 1.5T scanner using a flow-sensitive alternating inversion recovery (FAIR) pulse sequence, performed both at baseline and 12 min after intravenous administration of acetazolamide. T(1) was measured in conjunction with the FAIR scan in order to calculate quantitative CBF. The CBF maps were segmented to separate gray matter (GM) from white matter (WM) for region-of-interest (ROI) analyses. Post- acetazolamide CBF values (ml/100 g/min, mean +/- SD) of 87.5 +/- 12.5 (GM) and 46.1 +/- 10.8 (WM) represented percent increases of 37.7% +/- 24.4% (GM) and 40.1% +/- 24.4% (WM). Day-to-day differences in baseline CBF were -1.7 +/- 6.9 (GM) and -1.4 +/- 4.7 (WM) or, relative to the mean CBF over both days for each subject, -2.5% +/- 11.7% (GM) and -3.8% +/- 13.6% (WM) Day- to-day differences in absolute post-ACZ CBF increase were -2.5 +/- 6.8 (GM) and 2.7 +/- 9.4 (WM) or, relative to the mean CBF increase over both days for each subject, -4.7% +/- 13.3% (GM) and 9.1% +/- 26.2% (WM). Thus, FAIR- based CBF measurements show satisfactory reproducibility from day to day, but with sufficient variation to warrant caution in interpreting longitudinal data. The hemispheric asymmetry of baseline CBF and post-acetazolamide CBF increases varied within a narrower range and should be sensitive to small changes related to disease or treatment.  相似文献   
998.
PURPOSE: Important criteria for optimized stent implantation are high radial force and complete apposition of the stent itself. The aim of this study was to develop a simple method to assess these parameters under controlled experimental conditions and to compare vascular stents of different designs with regard to these parameters. MATERIALS AND METHODS: Five balloon-expandable stents of different designs (Jostent Flex, MAC stent, ML-Tristar, ML-Ultra, and S670) were tested. Fourteen stents of each type were implanted in a curved plastic vessel model (curve radius, 10 mm; lumen diameter, 3.5 mm) with use of a balloon inflation pressure of 12 atm. Part of the model was a nonflexible eccentric stenosis which was 2 mm or 8 mm in length. After stent implantation, a stenosis of 10%-70% was induced and radial force of the stent struts was measured at the site of the stenosis. The apposition of the stent to the vessel wall was imaged by high-resolution radiography. RESULTS: Analysis of variance showed significant differences of radial force between the tested stents (P <.001). The ML-Tristar and ML-Ultra stents had the highest radial force with maximum mean values of 687 cN and 846 cN at a stenosis of 70% in the model with the long stenosis. The radial force of the S670 stent was the lowest whereas the MAC stents showed an intermediate radial force. Radial force of the ML-Ultra stent was as much as 3.8 times higher than the force of the S670 stent (P <.001). Fifty percent of the ML-Tristar and ML-Ultra stents did not expand sufficiently to touch the vessel surface at the outer curvature. With an inflation pressure of 17 atm, complete apposition of these stents was achieved. The highest number of apposition irregularities was found in the S670 group (13 of 14 stents), whereas the MAC stents revealed the lowest number of irregular appositions (three of 14 stents). A significant correlation was found between the number of interconnecting struts and the number of irregular apposition events (P <.01). CONCLUSIONS: This model allows an accurate in vitro evaluation of different stent parameters, such as apposition to the vessel wall and radial force. None of the investigated stents showed optimal results with respect to both parameters. The apposition behavior was significantly influenced by the architecture of the stents.  相似文献   
999.
The purpose of the present study was to examine the effect of ad libitum ingestion of a carbohydrate-electrolyte solution (CES) with 150 mg x L (-1) caffeine (CAF) on urinary CAF concentration after 4 h of endurance exercise. Fifty-eight healthy and well-trained male subjects ingested ad libitum a 7 % CES with 150 mg x L (-1) CAF during 4 h cycling at 50 % of maximal work capacity. Total fluid consumption (mean +/- SE) was 2799 +/- 72 mL and CAF intake was 420 +/- 11 mg (5.7 +/- 0.2 mg x kg (-1) body weight). The post-exercise urinary CAF concentration (4.53 +/- 0.25 microg x mL (-1)) was below the doping level of the International Olympic Committee (12 microg x mL (-1)) in all subjects (range 1.20 - 10.84 microg x mL (-1)). A highly positive correlation was observed between CAF intake and post-exercise urinary CAF concentration (r = 0.68, p < 0.001). It is concluded that ad libitum ingestion of a CES with 150 mg x L (-1) CAF during 4 h cycling resulted in post-exercise urinary concentration below the doping level in all subjects.  相似文献   
1000.
We aimed to assess the prevalence, incidence, age-of-onset and diagnostic stability of threshold and subthreshold anorexia nervosa (AN) and bulimia nervosa (BN) in the community. Data come from a prospective-longitudinal community study of 3021 subjects aged 14–24 at baseline, who were followed up at three assessment waves over 10 years. Eating disorder (ED) symptomatology was assessed with the DSM-IV/M-CIDI at each wave. Diagnostic stability was defined as the proportion of individuals still affected with at least symptomatic eating disorders (EDs) at follow-ups. Baseline lifetime prevalence for any threshold ED were 2.9 % among females and 0.1 % among males. For any subthreshold ED lifetime prevalence were 2.2 % for females and 0.7 % for males. Symptomatic expressions of EDs (including core symptoms of the respective disorder) were most common with a lifetime prevalence of 11.5 % among females and 1.8 % among males. Symptomatic AN showed the earliest onset with a considerable proportion of cases emerging in childhood. 47 % of initial threshold AN cases and 42 % of initial threshold BN cases showed at least symptomatic expressions of any ED at any follow-up assessment. Stability for subthreshold EDs and symptomatic expressions was 14–36 %. While threshold EDs are rare, ED symptomatology is common particularly in female adolescents and young women. Especially threshold EDs are associated with a substantial risk for stability. A considerable degree of symptom fluctuation is characteristic especially for subthreshold EDs.  相似文献   
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