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Sigita Gelman rius Sakalauskas Romanas Zykus rius Pranculis Rytis Jurkonis Irma Kuliavienė Arūnas Lukoševičius Limas Kupčinskas Juozas Kupčinskas 《World journal of gastroenterology : WJG》2020,26(38):5836-5848
BACKGROUND Degree of portal hypertension(PH) is the most important prognostic factor for the decompensation of liver cirrhosis and death, therefore adequate care for patients with liver cirrhosis requires timely detection and evaluation of the presence of clinically significant PH(CSPH) and severe PH(SPH). As the most accurate method for the assessment of PH is an invasive direct measurement of hepatic venous pressure gradient(HVPG), the search for non-invasive methods to diagnose these conditions is actively ongoing.AIM To evaluate the feasibility of parameters of endogenously induced displacements and strain of liver to assess degree of PH.METHODS Of 36 patients with liver cirrhosis and measured HVPG were included in the casecontrol study. Endogenous motion of the liver was characterized by derived parameters of region average tissue displacement signal(dantero, dretro, d RMS) and results of endogenous tissue strain imaging using specific radiofrequency signal processing algorithm. Average endogenous strain μ and standard deviation σ of strain were assessed in the regions of interest(ROI)(1 cm × 1 cm and 2 cm × 2 cm in size) and different frequency subbands of endogenous motion(0-10 Hz and 10-20 Hz).RESULTS Four parameters showed statistically significant(P 0.05) correlation with HVPG measurement. The strongest correlation was obtained for the standard deviation of strain(estimated at 0-10 Hz and 2 cm × 2 cm ROI size). Three parameters showed statistically significant differences between patient groups with CSPH, but only dretro showed significant results in SPH analysis. According to ROC analysis area under the curve(AUC) of the σROI[0…10 Hz, 2 cm × 2 cm] parameter reached 0.71(P = 0.036) for the diagnosis of CSPH; with a cut-off value of 1.28 μm/cm providing 73% sensitivity and 70% specificity. AUC for the diagnosis of CSPH for μROI[0…10 Hz, 1 cm × 1 cm] was 0.78(P = 0.0024); with a cut-off value of 3.92 μm/cm providing 73% sensitivity and 80% specificity. Dretro parameter had an AUC of 0.86(P = 0.0001) for the diagnosis of CSPH and 0.84(P = 0.0001) for the diagnosis of SPH. A cut-off value of-132.34 μm yielded 100% sensitivity for both conditions, whereas specificity was 80% and 72% for CSPH and SPH respectively.CONCLUSION The parameters of endogenously induced displacements and strain of the liver correlated with HVPG and might be used for non-invasive diagnosis of PH. 相似文献
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Peter Kokol Marjan Mernik Jernej Završnik Kurt Kancler Ivan Malčić 《Journal of medical systems》1994,18(4):201-206
Computerized information systems, especially decision support systems, have become an increasingly important role in medical applications, particularly in those where important decision must be made effectively and reliably. But the possibility of using computers in medical decision making is limited by many difficulties, including the complexity of conventional computer languages, methodologies and tools. Thus a conceptual simple decision making model with the possibility of automating learning should be used. In this paper we introduce a cardiological knowledge-based system based on the decision tree approach supporting the mitral valve prolapse determination. Prolapse is defined as the displacement of a bodily part from its normal position. The term mitral valve prolaps (PMV), therefore, implies that the mitral leaflets are displaced relative to some structure, generally taken to be the mitral annulus. The implications of the PMV are the following: disturbed normal laminar blood flow, turbulence of the blood flow, injury of the chordae tendinae, the possibility of thrombus's composition, bacterial endocarditis, and finally hemodynamic changes defined as mitral insufficiency and mitral regurgitation. Uncertainty persists about how it should be diagnosed and about its clinical importance. It is our deep belief that the echocardiography enables properly trained experts armed with proper criteria to evaluate PMV almost 100%. But unfortunately, there are some problems concerned with the use of echocardiography. In that manner we have decided to start a research project aimed at finding new criteria and enabling the general practitioner to evaluate PMV using conventional methods and to select potential patients from the general population. To empower one to perform needed activities we have developed a computer tool called ROSE (computeRised prOlaps Syndrom dEtermination) based on algorithms of automatic learning. This tool supports the definition of new criteria and the selection of potential PMV-patients. 相似文献
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L Krapac A Krmpoti? L Pavi?evi? Z Domljan 《Arhiv za higijenu rada i toksikologiju》1992,43(3):255-262
The subjects in the study were 114 persons receiving a disability pension or referred for disability assessment. They were placed in two groups of 57 persons each, one with marked cervicobrachial syndrome and the other without. The latter group was chosen by the method of equivalent pairs with regard to sex and age. All subjects underwent a clinical examination and a standardized questionnaire was completed. The questionnaire pertained to the state of health, focussing on the amount and type of physical burdening at the workplace and on activities outside the workplace. Sixty-five percent of the subjects were aged from 51 to 60 years. A statistically significant difference was established between earlier occupation and cervicobrachial syndrome. Cervicobrachial syndrome was found in 31.6% of unskilled workers and 12.3% of the controls (P < 0.05). A forced body posture during work was recorded in 74% of the subjects with the syndrome and in 50% of the control subjects (P < 0.05). Repetitive movements at work were reported by a large number of subjects with cervicobrachial syndrome (71.9:49.1%; P < 0.05) who also claimed to strain the arms (84.2:61.4%; P < 0.05) and burden the cervical spine (68.5:40.4%; P < 0.05) during household activities to a significantly greater extent than the controls. A possible preventive approach to the occurrence and progression of cervicobrachial syndrome is discussed. 相似文献
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In the neurosurgical approach to intracranial aneurysms which are often accompanied by arterial spasm and cortical ischaemia, monitoring procedures aim to obtain useful information on cerebral function. SEPs evoked by stimulation of the median nerve at the wrist and of the tibial nerve at the medial malleolus were registered in 45 patients with intracranial aneurysms during neurosurgical procedures. Our results show SEP abnormalities during different stages of neurosurgical procedures in 36 patients out of the monitored 45. Significant abnormalities of SEPs with respect to the control group were decrease of the amplitude of N 20-P 25 complex, lengthening of the absolute latency of the waves N 20- and P 25 and lengthening of the central conduction time (CCT) (N 13-N 20). The greatest SEP abnormalities were registered during the neurosurgical approach to aneurysm and during the clipping procedure. However, the changes were reversible in the majority of the patients. The aim of this paper was to focus on early detection of some cerebral function disturbances during the neurosurgical procedure as well as the prevention of possible brain damage. 相似文献
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Ivan Bojanić Alan Ivković Igor Borić 《Knee surgery, sports traumatology, arthroscopy》2006,14(5):491-496
The aim of this paper is to report on three cases of symptomatic osteochondritis dissecans of the humeral capitellum in adolescent
gymnasts, two females and one male. In all the cases arthroscopic surgery was performed. During arthroscopy, loose osteochondral
fragments were removed, the defect was debrided and microfractures were performed. All the three patients regained the full
range of motion of the affected elbow, and returned to the high-level gymnastics within a period of 5 months. At 12 months
follow-up, all the three patients remained symptomless and were participating in high-level gymnastics. A combination of arthroscopy
and the microfracture technique is a reliable method with excellent short-term results in the treatment of the osteochondritis
dissecans of the elbow. 相似文献