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1.
Ruggieri  PM; Laub  GA; Masaryk  TJ; Modic  MT 《Radiology》1989,171(3):785-791
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study.  相似文献   
2.
R L Telander  M Spencer  J Perrault  D Telander  A R Zinsmeister 《Surgery》1990,108(4):717-23; discussion 723-5
The purpose of this study was to carry out a long-term study of the ileoanal anastomosis (IAA) in children and young adults, comparing the straight IAA to the J pouch. One hundred twenty-one young people who had undergone IAA were studied, with 114 available for long-term follow-up. One hundred one were 18 years and under. Forty-nine patients had a straight IAA and 72 had a J-pouch reservoir. There were no deaths. After surgery, three children had intraabdominal sepsis and one had pelvic sepsis, but it did not lead to excision of the IAA. The mean stool frequency in all 114 patients was 5.0 +/- 2.5 per day and 1.2 +/- 1.1 at night. The mean number of stools for the straight IAA was 6 per day and 2.1 at night. The mean number of stools for the straight IAA with balloon dilations was 5.8 per day and 1.2 at night, and for the J pouch it was 4 per day and 1 at night. Patients with both the J pouch and straight IAA had good to excellent sensation, with patients with the J pouch always able to distinguish flatus from stool in 87% of patients and almost always in 13%. Daytime continence was very good in both groups. Moderate nighttime loss of stool occurred in 10 patients, 6 with a straight IAA and 4 with a J pouch. Ninety-five percent of the 114 patients were satisfied or very satisfied, with most children with a J pouch very satisfied. The J pouch remains the procedure of choice in young people.  相似文献   
3.
Paediatric dacryocystorhinostomy   总被引:1,自引:0,他引:1  
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease.  相似文献   
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Factors influencing women to undergo screening mammography   总被引:2,自引:0,他引:2  
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7.
Background: Inhaled administration of milrinone reduces pulmonary artery pressure. Pulmonary hypertension (PH) and right heart failure are associated with difficult separation from cardiopulmonary bypass (CPB). Therefore, inhaled milrinone could facilitate separation from CPB. Objective: To determine the impact and timing of administration of inhaled milrinone. Methods: A retrospective analysis of our experience on high-risk patients receiving inhaled milrinone was conducted to evaluate the postoperative course after administration of the drug. Results: Seventy-three patients received inhaled milrinone from June 2002 to February 2005. Mean age was 64 ± 13 years, with a mean preoperative Parsonnet score of 27 ± 14. Inhaled milrinone (5 mg) was administered before (n = 30) or after (n = 40) CPB, three patients had off-pump procedures and were excluded. CPB time was 145 ± 78 min with cross-clamping times of 91 ± 56 min without any significant difference between groups. Fifty-four patients (74%) had difficult separation from CPB, 14 patients (19%) required an intra-aortic balloon pump and 10 patients (14%) needed emergency reinitiation of CPB for hemodynamic instability. Ten patients died in the perioperative period (13.7%). Patients receiving inhaled milrinone prior to CPB initiation had a lowering pulmonary artery pressure after CPB (p < .01) and had less emergency reinitiation of CPB after weaning (3% vs 23%, p = .02) as compared to those with administration after CPB. No detectable side effects were directly linked to the administration of the drug. Conclusion: In this high-risk cohort, use of inhaled milrinone was well tolerated. Administration before initiation of CPB could help weaning from CPB.  相似文献   
8.
Objective: Whatever the surgical technique used, false aneurysm formation is one of the long-term complications of repair of aortic coarctation. Conservative management is associated with a 100% rate of rupture. The conventional surgical approach is complex and associated with high morbidity and mortality rates. We report our experience of endovascular management of pseudo-aneurysms after previous surgical repair of congenital aortic coarctation. Methods: Between October 2005 and 2006, stent-grafting of pseudo-aneurysms after previous surgical repair of congenital aortic coarctation was performed in four patients. Median age was 31.5 years (range: 24–38). Two patients had undergone two previous interventions. The last previous surgery consisted of graft interposition (N = 2), subclavian flap aortoplasty (N = 1) and aorto-aortic bypass (N = 1). Median size of the pseudo-aneurysm was 31.5 mm (range: 20–58). Mean time between the last surgery and endovascular treatment was 24 years (range: 3–32). One patient was treated emergently because of hemoptysis in relation with an aorto-bronchial fistula, the three other patients were treated electively. A transfemoral approach was used in all patients. The Zenith TX2® (Cook) thoracic stent-graft was used in all the patients, one patient underwent previous dilatation at the coarctation level. When present, the ostium of the left subclavian artery was always covered (N = 3). Results: No major complication occurred during the procedure and no patient died during the follow-up. One patient presented a type II endoleak which spontaneously healed during the first month. Another patient with his left subclavian artery covered presented claudication of the left arm requiring a carotid-subclavian bypass. After a median follow-up of 7.5 months (range: 1–12.9), the patients were asymptomatic and CT scans demonstrated complete exclusion of all treated postcoarctation aneurysms without recoarctation and without any stent-graft-related complication. Conclusions: The endovascular management of pseudo-aneurysms after previous surgical repair of congenital aortic coarctation is feasible. This approach was safe and effective. Long-term clinic and imaging follow-up is mandatory.  相似文献   
9.
Epithelial coverage of a laryngotracheal wound is an important factor in preventing stenosis, and endoscopic transplantation of a free mucosal graft without stents or sutures would be a significant therapeutic advance. In vitro and in vivo canine studies were performed to explore the feasibility of transplantation with a low-power diode laser (400 mW) enhanced by indocyanine green dye-doped albumin. The tensile strength of graft adherence in 10 cadaver larynges was strong (35.25 ± 10.39 g). Survival studies in live canine models with a specially designed endoscopic instrument set showed excellent healing at 6, 14, and 28 days. Healing was documented with photography and by histologic examination. Successful endoscopic transplantation of a free mucosal graft should improve results of treatment for laryngotracheal stenosis and laryngeal reconstructive surgery.  相似文献   
10.
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