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51.
An algorithm was developed in this study, using rule-based fuzzy logic, to enable masses that are hard to recognize or detect in mammograms to become more readily perceptible. Small lesions, such as microcalcifications and other masses that are hard to recognize, especially on film scan mammograms, were processed through segmentation. A total of 40 mammograms were used and they were classified by radiologists into three groups: those with microcalcifications (n=15), those with tumours (n=15), and those with no lesions (n=10). Five mammograms were taken as training data sets from each of the groups with microcalcifications and tumours. The algorithm was then applied to data not taken for training. The algorithm achieved a mean accuracy of 99% compared with the findings of the radiologists.  相似文献   
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European Journal of Orthopaedic Surgery & Traumatology - This retrospective study aimed to compare the clinical and radiological outcomes of patients who underwent biplane chevron medial...  相似文献   
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Purpose

The aim of this study was to compare partial cystectomy and internal drainage of the cyst cavity with cystojejunostomy for the surgical treatment of giant hepatic hydatid cysts.

Methods

Patients who underwent any type of surgical treatment between March 2009 and May 2013 for giant hepatic hydatid cysts were retrospectively evaluated. The data collected included demographic variables, diagnostic methods, surgical procedures, morbidity and mortality rates.

Results

Twenty-eight patients who underwent surgery for giant hepatic hydatid cysts were included. There were 16 (57 %) female patients, with a mean age of 32.8 years. The diagnostic methods primarily included abdominal ultrasonography and computed tomography, which were performed in 62 % of the patients. The patients were divided into two groups with respect to the treatment modality: Group A (n = 13) treated with cystojejunostomy and Group B (n = 15) treated with partial cystectomy. The overall rate of cavity-related complications was 25 % in Group B, whereas none of the patients in Group A had a cavity-related complication during the follow-up period (p < 0.05).

Conclusion

Cystojejunostomy is an effective and safe surgical approach for the treatment of giant hepatic hydatid cysts, with a lower rate of morbidity than partial cystectomy, and thus may be the surgical treatment of choice for giant hepatic hydatid cysts.  相似文献   
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Eighteen patients underwent surgery for traumatic mitral regurgitation following percutaneous mitral valvuloplasty (PMV). Three patients required emergency surgery (delay less than 6 hours). In the remaining cases, the operation was performed one week after PMW (n = 11) or delayed for up to 3 months (n = 4). The operative findings were: ruptured papillary muscle (n = 1); torn anterior leaflets (n = 4), torn posterior leaflet (n = 1), anterior paracommissural tear (n = 3), posterior paracommissural tear (n = 9). Associated lesions included left atrial thrombosis (n = 2) and greater than 1 cm atrial septal defect (n = 4). Conservative mitral valve surgery was possible in over half the cases (n = 10), including two extensive tears of the anterior leaflet. The other patients required mitral valve replacement (n = 8). There were no postoperative complications in any of the patients.  相似文献   
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The results of percutaneous mitral valvuloplasty in 5 adult patients with mitral stenosis are presented. The average age was 55 years (37-72 years); 4 patients were in functional Class III and 1 in Class IV. The three oldest patients were in atrial fibrillation, and 2 of them had severe valvular and subvalvular lesions. Valvuloplasty was carried out with a "Trefoil" balloon (3 X 12 mm; effective cross sectional area at maximal inflation: 3.8 cm2). The procedure was successful in 4 patients. In the other patient, it was not possible to position the balloon across the stenotic valve. After valvuloplasty, the mean mitral gradient decreased (14 +/- 5 to 6 +/- 2 mmHg, p less than 0.05) without a significant change in cardiac index (2.9 +/- 0.5 vs 2.7 +/- 0.4 l/mn/m2; NS): this indicated an increased mitral valve surface area (1.1 +/- 0.2 to 1.8 +/- 0.05 cm2, p less than 0.05). In parallel, echocardiographic measurements of mitral valve surface area increased from 0.9 +/- 0.2 to 1.8 +/- 0.3 cm2, p less than 0.05, and Doppler pressure halt time fell from 220 +/- 50 to 116 +/- 13 ms, p less than 0.05. There were no operative complications and, in particular, no resulting angiographic mitral regurgitation. These preliminary results suggest that percutaneous mitral valvuloplasty may be a valuable alternative therapeutic procedure to surgery in selected patients.  相似文献   
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The benefits of surgical correction of mitral incompetence were assessed in 51 patients by comparing pre and postoperative catheter and quantitative angiographic results. The mean age of the patients was 43.5 +/- 12.3 years. The mitral lesions were elongation or ruptured chordae (27 cases), valvular perforation due to endocarditis (1 case) and the usual rheumatic disease in 23 cases. Hemodynamic investigation was carried out on average 2 months before operation and 29 +/- 22 months after surgery. The following angiographic parameters were measured : indexed end diastolic and end systolic volumes (EDV and ESV), ejection fraction (EF), myocardial mass (MM) and its ratio to EDV (hypertrophy coefficient : HC) and the geometry of the ventricle as assessed by diastolic and systolic coefficients of excentricity (DE and SE). Surgery comprised 13 mitral valvuloplasties and 38 valve replacements. Patients who suffered perioperative myocardial infarction or who had a residual valvular lesion were excluded from the study. After surgery, the hemodynamic state was considerably improved with a significant decrease in pulmonary capillary pressures (11 +/- 5 compared to 17 +/- 6 mmHg, p less than 0.09) and mean pulmonary artery pressures (19 +/- 7 compared to 27 +/- 11, p less than 0.01) and increase in cardiac index (2.8 +/- 0.7 compared to 2.3 +/- 0.6 l/min/m2, p less than 0.01). There was an associated decrease in ventricular volumes (EDV : 115 +/- 44 compared to 165 +/- 43, p less than 0.01) (ESV : 60 +/- 39 compared to 77 +/- 22, p less than 0.001). The reduction in myocardial mass was less spectacular (129 +/- 40 compared to 148 +/- 32, p less than 0.01) with a resulting increase in the HC (1.10 +/- 0.26 compared to 0.88 +/- 0.17, p less than 0.001). The geometry of the LV was less spherical in diastole (DE 0.76 +/- 0.08 compared to 0.70 +/- 0.08, p less than 0.001) and in systole (SE = 0.83 +/- 0.06 compared to 0.77 +/- 0.08, p less than 0.001). The EF fell slightly but this was not statistically significant (0.51 +/- 0.13 compared to 0.53 +/- 0.09 NS). The surgical result of 14 patients with PCP greater than or equal to 13 mmHg was considered hemodynamically incomplete, and this was confirmed by a lower cardiac index than in the remaining 37 patients (2.4 +/- 0.5 compared to 3.0 +/- 0.7, p less than 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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