Computerized analysis of lesions in US images of the breast

RATIONALE AND OBJECTIVES: Breast sonography is not routinely used to distinguish benign from malignant solid masses because of considerable overlap in their sonographic appearances. The purpose of this study was to investigate the computerized analyses of breast lesions in ultrasonographic (US) images in order to ultimately aid in the task of discriminating between malignant and benign lesions. MATERIALS AND METHODS: Features related to lesion margin, shape, homogeneity (texture), and posterior acoustic attenuation pattern in US images of the breast were extracted and calculated. The study database contained 184 digitized US images from 58 patients with 78 lesions. Benign lesions were confirmed at biopsy or cyst aspiration or with image interpretation alone; malignant lesions were confirmed at biopsy. Performance of the various individual features and output from linear discriminant analysis in distinguishing benign from malignant lesions was studied by using receiver operating characteristic (ROC) analysis. RESULTS: At ROC analysis, the feature characterizing the margin yielded Az values (area under the ROC curve) of 0.85 and 0.75 in distinguishing between benign and malignant lesions for the entire database and for an "equivocal" database, respectively. The equivocal database contained lesions that had been proved to be benign or malignant at cyst aspiration or biopsy. Linear discriminant analysis round-robin runs yielded Az values of 0.94 and 0.87 in distinguishing benign from malignant lesions for the entire database and for the equivocal database, respectively. CONCLUSION: Computerized analysis of US images has the potential to increase the specificity of breast sonography.     

Artificial liver

Without transplantation, approximately 90% of patients with fulminant hepatic failure die. If patients receive a liver transplant, there is often a lag between the need for and the availability of a donor liver. Therefore, there is a definite need for a liver support system to support the patient's own liver function in fulminant hepatic failure and while awaiting transplantation. We have developed an artificial liver system that not only eliminates lipophilic toxins such as phenols, fatty acids, and mercaptans, but also hydrophilic ones such as ammonia. This artificial liver system consists of a monitor, an extracorporeal blood circuit that uses a hydrophilic polysulfone high-flux dialyzer to remove water-soluble metabolites, and a novel hydrophilic liquid membrane filter to remove lipophilic toxins. In more than 100 in vitro experiments using porcine (5 I) blood, the system was evaluated for its ability to remove toxins that are normally increased in hepatic failure. We found that phenol, cresol, and short- and medium-chain fatty acids can be almost completely eliminated from the blood within 5 h. In animal experiments using pigs, we also found no significant changes of blood gases, liver parameters, electrolytes, and blood cell counts.     

The valvo-pump, an axial blood pump implanted at the heart valve position: concept and initial results

The valvo-pump, an axial nonpulsatile blood pump implanted at the heart valve position, has been developed. The valvo-pump consists of an impeller and a motor, which are encased in a housing. An impeller with 5 vanes (22.0 mm in diameter) is used. The impeller is connected to a samarium-cobalt-rare earth magnet direct current (DC) brushless motor measuring 21.3 mm in diameter and 18.5 mm in length. Sealing is achieved by means of a ferrofluidic seal. A pump flow of 10.5 L/min was obtained at a pump differential pressure of 3.3 kPa (25 mm Hg), and a flow of 4.9 L/min was obtained at 7.0 kPa (53 mm Hg). Sealing was kept perfect against a pressure of 29.3 kPa (220 mm Hg) at 9,000 rpm.     

Elimination of an artificial immune complex by plasmapheresis in rabbits

The behavior of an artificial immune complex was investigated in 15 rabbits. The immune complex was labeled with iodine-125 (125I). The advantage was that the immune complex could not be metabolized without being eliminated by the kidney. This artificial immune complex was injected in a dosage of 0.8 microgram, in 2 rabbits, 5.0 micrograms in 4 rabbits, 10 micrograms in 3 rabbits, 20 micrograms in 2 rabbits, and 40 micrograms in 4 rabbits on two consecutive days. One group (n = 9) was treated with plasmapheresis: the other (n = 6) was a control group that did not undergo plasmapheresis. A miniaturized plasmapheresis system eliminated the immune complex very effectively with an average exchange volume of 95.7 ml per treatment. The increasing concentration of the immune complex in the blood before the next plasmapheresis treatment was probably an expression of mobilization of the immune complex from different organs. The animals of the plasmapheresis group were in better condition than the control group.     

Biventricular Bypass: Alternative to Univentricular Bypass and Total Artificial Heart–Bridge

Left ventricular and biventricular bypasses (LVBs, BVBs) were performed in 102 experiments in sheep, goats, and donkeys. Biventricular bypass was performed in the assisted circulation mode or in the paracorporeal artificial heart bridge (PCAHB) mode when the natural heart fibrillates. During implantation of artificial ventricles instead of a heart-lung bypass, counterpulsation was used. Several types of connective conduits were developed and tested in experiments. The conduits included bifurcational connective pipes that permit "intake" of blood into artificial ventricles from atria and ventricles of the natural heart simultaneously and consequently provide effective blood flow through shunts not depending on the state of the natural heart (acute cardiac weakness or asystole). Monitoring gas content (PO2, PCO2, and pH) in the myocardium of both ventricles suggested development of right ventricular failure under conditions of LVB before hemodynamic changes occurred and confirmed the preferability of BVB over other methods of assisted circulation, as it is most effective and capable of normalizing short-term cardiac disturbances in the course of the 1st 2 days. Survival time of experimental animals (2-3 days for dogs, 5-12 days for sheep, goats, and donkeys) is sufficient to overcome acute cardiac insufficiency. This suggests that BVB in the assisted circulation mode or PCAHB mode can serve as a bridge for cardiac transplantation for the time of search for the available organ.     

Changes in patterns of left ventricular hypertrophy after aortic valve replacement for aortic stenosis and regurgitation with St. Jude Medical cardiac valves

In this study, we analyzed the extent and pattern of regression of left ventricular (LV) hypertrophy after aortic valve replacement in patients with aortic stenosis (AS) and compared the results with those of another group of patients with aortic regurgitation (AR). Seventy patients who underwent isolated aortic valve replacement were divided into 2 groups. Group 1 was comprised of 29 patients who underwent aortic valve replacement for aortic stenosis, and Group 2 of 41 patients who underwent aortic valve replacement for aortic regurgitation. A third group of 10 healthy subjects served as a healthy control group. Echocardiographic studies were done before the operation and 5 years postoperatively. At follow-up, a significant reduction in the left ventricular mass was found in both groups, but it remained significantly greater than in the healthy control group. The ratio of LV wall thickness to radius (th/r) in Group 1 decreased significantly, and at follow-up it was within the normal value. In Group 2, the th/r ratio increased, and at follow-up it was within the normal value. After aortic valve replacement, the wall thickness remained significantly greater than normal for patients with AS, and the chamber radius remained significantly greater than normal for patients with AR. For these reasons, LV hypertrophy still existed in both groups at postoperative follow-up. The actuarial survival rate was 85.3% at 16 years for Group 1 and 83.4% at 18 years for Group 2. There was no significant difference in the long-term survival rates between the 2 groups. Actuarial freedom from valve-related events was 91.9% at 16 years for Group 1 and 82% at 18 years for Group 2. There was no significant difference in the valve-related event free curves between groups. After 5 years of follow-up, th/r reached normal for both groups, indicating remodeling of the LV geometry after aortic valve replacement.     

Development of a miniature undulation pump for the distributed artificial heart

Research of the distributed artificial heart is important not only to acquire the means of individual organ perfusion but also to clarify the characteristics of the organ and the mechanism of blood distribution. To investigate the distributed artificial heart, the miniature undulation pump was developed. The outer diameter and the thickness of the developed pump were 38 mm and 11 mm, respectively. The priming volume of the pump was 3.2 ml. The total size including the motor unit was 38 mm in diameter and 32 mm in length. The total weight was 67.5 g. The total volume was 27.5 ml. The pump was driven with pulse width modulation by using a 1 chip motor controller. More than 5 L/min of continuous output could be obtained. The results showed that the developed miniature undulation pump system had enough performance for individual organ perfusion.     

硅油支持眼的人工虹膜膈植入

目的 总结硅油支持眼的人工虹膜膈植入的临床效果。方法 回顾性研究11例硅油支持眼人工虹膜膈植入手术适应症，手术效果及手术并发症。结果 11例人工虹膜膈植入眼原发眼病中，7例(7／11，64％)为严重外伤眼，2例(2／11，18％)为增埴期糖尿病性视网膜病变合并牵引性视网膜脱离眼，1例(1／11，9％)为严重PVR后复发性视网膜脱离眼，1例(1／11。9％)为Coats病眼；7例(／11，64％)人工虹膜膈有效地防止了硅油接触角膜，11例人工虹膜膈植入眼。均未引起视力的进一步下降；其手术后并发症主要为低眼压和人工虹膜膈表面的纤维膜形成。结论 硅油支持眼的开放性人工虹膜膈植入可通过自然隔断，建立房水循环来维持眼压，有效地防止硅油接触角膜引起并发症。     

A comparison of Rasch with Likert scoring to discriminate between patients' evaluations of total hip replacement surgery

The purpose of this study was to examine whether there are advantages in terms of outcome assessment of using Rasch methods of scoring the 12-item Oxford Hip Score (OHS) questionnaire over conventionally Likert scores. As part of a prospective cohort study of total hip replacements in five former regions of England the OHS was sent to patients pre-operatively, at 3 months and 1 year post-operatively. Post-operative data was collected on over 5000 cases. Based on the level of satisfaction with surgery, patients were divided into satisfied and dissatisfied. Analyses were performed to test the relative precision (RP) of Rasch scoring vs. conventionally Likert scores in discriminating the groups experiencing different level of satisfaction. Considerable gains in precision were achieved with Rasch scoring methods when groups were compared 3 and 12 months post-operatively. The results from the current study suggest that in some situations there may be substantial gains in measuring health related outcomes using Rasch-based scoring methods.     

酶制剂Cerezyme治疗高雪氏病效果观察

目的　酶制剂cerezyme替代疗法治疗高雪氏病 4年小结。方法　 Cerezyme初剂量 6 0U/kg ,每 2周 1次静脉滴注 ,2年后疗效好转剂量改为 30U/kg。结果 　 1 5例用药 4年以上的患者 ,血红蛋白平均增加 2 1g/L ,1 4例血小板近 1 2月恢复正常 ;脾功能亢进得到改善 ,肝脾回缩 9.3%和 6 0 .6 % ,肝功能治疗 6个月后大多恢复正常 ;身高平均增长 2 5 6厘米 ,体重平均增加 1 4 5公斤 ,生活质量明显提高。结论　 在基因治疗尚未广泛应用之前 ,酶替代疗法仍是唯一改善症状的有效措施