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991.
BACKGROUND: High-grade dysplasia of the esophageal mucosa has been shown to be a precursor to adenocarcinoma. In addition to esophagectomy, multiple ablative endoscopic techniques have evolved for the management of this condition. As a surgical alternative to esophagectomy, we describe for the first time a new option in the treatment of high-grade dysplasia. MATERIALS AND METHODS: Two patients with a history of gastroesophageal reflux disease (GERD) underwent upper gastrointestinal endoscopy which demonstrated high-grade dysplasia of the distal esophagus. The first patient had a short segment (0.5-1.0 cm), and the second patient had a longer (2 cm) segment of dysplasia. The patient is placed in the modified lithotomy position. Five trocars are placed as if to perform a fundoplication. A complete circumferential mobilization of the esophagus is performed. The short gastric vessels are divided with the harmonic scalpel, to free up the fundus of the stomach. An anterior horizontal gastrotomy is performed three to four centimeters below the gastroesophageal junction. A solution of epinephrine and normal saline (1:100,000) is injected into the mucosa at the Z-line and, utilizing specially designed hook electrocautery, the mucosa is incised circumferentially around a lighted bougie. Using blunt dissection the mucosa is undermined, elevated, and excised in four quadrants. Three centimeters of the distal esophageal mucosa are resected. The gastrotomy is then closed using a linear stapler, and a 360 degrees fundoplication is performed around a 50 Fr bougie. RESULTS: High-grade dysplasia was identified in the specimens from both patients; however, neither patient was found to have carcinoma in situ or invasive esophageal cancer. Our first patient has been followed for twenty months, the second for ten months. Both patients underwent routine upper gastrointestinal endoscopy for surveillance of the healing process. At eight months, the mucosa of the first patient showed complete regeneration of squamous epithelium. Our most recent patient appears to be progressing without complications and has also demonstrated normal squamous epithelium at ten months postoperatively, without changes of Barrett's epithelium. CONCLUSION: The technique of laparoscopic transgastric esophageal mucosal resection is feasible and may be proven to be an alternative to esophagectomy for the management of high-grade dysplasia.  相似文献   
992.
RATIONALE AND OBJECTIVES: To evaluate the potential use of gadolinium (Gd)-based contrast media, especially that of Gadovist, a 1-molar Gd medium, in computed tomography (CT) and compare our findings with standard iodinated contrast media. MATERIAL AND METHODS: Using a live rabbit and an acrylic CT body phantom for comparative CT imaging of Gd- and I-based media. The images were acquired at 80, 100, and 120 kVp, using fixed standard beam filtration. The phantom study used serial dilutions of the Magnevist and Ultravist 300 (2.4-molar I), whereas the animal study used different volumes of Gadovist, Magnevist (0.5 molar Gd), and Ultravist administered intravenously. RESULTS: At 80 kVp for the same injection volumes of Gadovist and Ultravist, the image contrast enhancement of the aorta with Gadovist was 40% lower than that of Ultravist. In the phantom studies, however, for the same kVp settings the CT image contrast was up to fourfold higher for Gd compared with iodine when comparing the same molar concentrations of the two elements in the solutions. CONCLUSION: These results indicate a potential of Gd-based media for clinical CT angiography and provide incentive for further investigation of this subject.  相似文献   
993.
BACKGROUND: Arthroscopic stabilization for anterior shoulder instability has been reported to result in a higher rate of recurrent instability compared to traditional open techniques. PURPOSE: To test the null hypothesis that there is no difference in the clinical outcomes in patients with recurrent anterior shoulder instability treated with open or arthroscopic stabilization. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A consecutive series of 64 patients with recurrent anterior shoulder instability were randomized to receive either arthroscopic or open stabilization by a single surgeon. Magnetic resonance arthrogram studies were obtained preoperatively. These findings were compared to arthroscopic findings. Postoperative evaluations included range of motion, stability, and subjective assessments including Single Assessment Numeric Evaluation, Simple Shoulder Test, Western Ontario Instability Index, and University of California, Los Angeles evaluation. Failure was defined as a second dislocation, recurrent subluxation, or symptoms precluding return to previous work or unrestricted active military duty. RESULTS: Sixty-one patients, 29 who received open stabilization and 32 who received arthroscopic stabilization, were evaluated at a mean of 32 months postoperatively (range, 24-48 months). Patient demographics were equivalent. Preoperative magnetic resonance arthrogram findings were confirmed at arthroscopic examination. The mean operative time was significantly shorter for the arthroscopic repairs (59 vs 149 minutes; P < .001). There were 3 clinical failures (2 open stabilizations, 1 arthroscopic stabilization) by the established criteria. There was a statistically significant improvement from preoperative to postoperative Single Assessment Numeric Evaluation scores in both groups (P < .001). The mean loss of motion (compared to the contralateral shoulder) was greater in the open shoulders. Subjective evaluations were equal in both groups. Conclusion: Clinical outcomes after arthroscopic and open stabilization were comparable. Preoperative magnetic resonance arthrograms in shoulders with anterior instability allow an accurate diagnosis of intra-articular abnormality that correlates well with operative findings. Arthroscopic stabilization for recurrent anterior shoulder instability can be performed safely; the clinical outcomes are comparable to those after traditional open stabilization.  相似文献   
994.
“Dirty-appearing white matter” (DAWM) in multiple sclerosis (MS) is defined as a region(s) with ill-defined borders of intermediate signal intensity between that of normal-appearing white matter (NAWM) and that of plaque on T2-weighted and proton density imaging. To delineate the histopathology of DAWM, four formalin-fixed cerebral hemisphere slices of three MS patients with DAWM were scanned with T2- weighted and proton density sequences. The myelin water fraction (MWF) was obtained by expressing the short T2 component as a fraction of the total T2 distribution. Hemispheric sections were then stained with Luxol fast blue (LFB) for myelin phospholipids, for myelin basic protein (MBP) and 2’,3’-cyclic nucleotide 3’-phosphohydrolase (CNP) for myelin; Bielschowsky silver impregnation for axons; and for glial fibrillary acidic protein (GFAP) for astrocytes. Compared to NAWM, DAWM showed reduction in MWF, corresponding to a reduction of LFB staining. DAWM also showed reduced Bielschowsky staining. Quantitatively, the change in MWF in DAWM most consistently correlated with the change in LFB staining. The findings of this preliminary study suggest that DAWM is characterized by loss of myelin phospholipids, detected by the short T2 component, and axonal reduction. † Deceased  相似文献   
995.
Functional magnetic resonance imaging (fMRI) represents a useful tool for studying brain functions and the neural basis of cognition in healthy children and in those in disease states. Functional magnetic resonance imaging is a relatively new use of existing magnetic resonance imaging technology that allows scientists and practitioners to observe the brain at work. It is based on the observation that local increases in blood flow are related to neural activity. This review considers principles of functional magnetic resonance imaging, issues relevant to imaging children, and research using functional magnetic resonance imaging to examine cognitive processing in pediatric populations. The focus is specifically on language studies to review strengths, limitations, and practical applications of this technology with children. Future directions for functional magnetic resonance imaging are presented.  相似文献   
996.
997.
PURPOSE: To test the hypothesis that reactive oxygen species contribute to the cerebral hyperperfusion in Fabry disease. MATERIAL AND METHODS: We examined the effect of intravenous injection of ascorbate on cerebral blood flow (CBF) using magnetic resonance arterial spin tagging. Nineteen patients with Fabry disease and 15 control subjects were studied as part of a randomized double-blind placebo-controlled trial of enzyme replacement therapy (ERT). RESULTS: Vertebro-basilar hyperperfusion was observed in patients with Fabry disease. A decrease in systemic ascorbate levels relative to healthy controls was found in the patients. CBF decreased after ascorbate infusion in both control subjects and patients treated with ERT. The placebo group had a significantly delayed decrease in the CBF response after ascorbate infusion. Myeloperoxidase levels were elevated in Fabry patients, consistent with ongoing inflammatory processes in these patients. CONCLUSION: Increased CBF in Fabry disease may be related to increased production of reactive oxygen species, while low plasma ascorbate levels suggests a global redox imbalance. These abnormalities were improved by ERT. These observations have implications regarding oxidative processes contributing to accelerated atherosclerosis in Fabry disease.  相似文献   
998.
The use of contrast-enhanced magnetic resonance angiography (CE-MRA) in screening for suspected renovascular disease may result in increased detection of renal artery aneurysms. We report the CE-MRA findings at diagnosis and follow-up in nine hypertensive patients with unsuspected renal artery aneurysms. A search of renal CE-MRAs of suspected renal artery stenosis at two tertiary referral institutions over 5 1/2 years was performed. All patients underwent CE-MRA using a fast spoiled gradient echo technique (TR/TE/flip 5.1–6 ms/1.6 ms/40°), scan matrix 512×196–224, 1 excitation, FOV 400–450 mm×266–360 mm, 32–50 mm×1.5–2 mm interpolated slices. Gadolinium-enhanced 3D images were obtained during breath holding. Images were evaluated and post-processed on a workstation by a single operator. Nine patients with renal artery aneurysms out of a total of 912 cases were found, all involving the main artery or divisions proximal to the renal hilum. Renal arteries distal to the hilum were not consistently visualized. The aneurysm was bilobed in one patient, multilocular in another and unilocular in all others. Severe stenosis of the renal artery proximal to the aneurysm was present in two. Four patients underwent follow-up showing no change in aneurysm size. CE-MRA reliably identifies aneurysms involving the main renal arteries and proximal branches. Once diagnosed, CE-MRA offers a safe, non-invasive modality for surveillance of aneurysm if active intervention is not planned.  相似文献   
999.
The Patient Knowledge of, and Attitude and Behaviour towards Pressure Ulcer Prevention Instrument (KPUP) was developed and validated using a two‐stage prospective psychometric instrument validation study design. In Stage 1, the instrument was designed, and it is psychometrically evaluated in Stage 2. To establish content validity, two expert panels independently reviewed each item for appropriateness and relevance. Psychometric evaluation included construct validity and stability testing of the instrument. The questionnaire was administered to a convenience sample of 200 people aged more than 65 years, living independently in the community; reliability and stability were assessed by test/retest procedures, with a 1‐week interval. Mean knowledge scores at ‘test’ were 11.54/20 (95% CI = 11.10‐11.99, SD: 3.07), and ‘retest’ was 12.24 (95% CI = 11.81‐12.66, SD: 2.93). For knowledge, correlation between the test/retest score was positive (r=. 60), attitude section‐inter‐item correlations ranged from r = −.31 to r = .57 (mean intraclass correlation coefficient of r = .42), and internal consistency for the retest was the same as the test (α = .41 for the eight items). For health behaviours, individual inter‐item correlations for test items ranged from r = −.21 to r = .41 for the 13 standardised items. Psychometric testing of the KPUP in a sample of older persons in the community provided moderate internal consistency and general high test‐retest stability.  相似文献   
1000.

Purpose

The use of internal iliac artery balloons for prevention of hemorrhage in cases of placenta accreta is increasing. Most described complications of this technique are maternal and thromboembolic in nature. Complications related to vascular rupture are rare, their presentation is not well described, and the resultant neonatal consequences are infrequently reported.

Clinical features

A 35-yr-old term parturient with suspected placenta accreta underwent prophylactic endovascular placement of iliac balloons prior to Cesarean delivery. The patient complained of contraction-like pain during balloon placement, and an arterial wall tear was discovered after abdominal incision. This produced significant maternal bleeding and the birth of a neonate with an umbilical venous pH of 6.95 and Apgar scores of 3 and 7.

Conclusion

In addition to the known maternal risks, fetal risks must be considered when planning the placement of endovascular iliac balloons during pregnancy. We recommend continuous monitoring of maternal and fetal status when performing the procedure. Contraction-like pain during placement should raise the suspicion of arterial disruption.  相似文献   
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