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Objective:The abstraction of characteristics in CT perfusion image is crucial in the clinical diagnosis of brain infarction and cerebral tumor.Methods:After describing the relevant parameters of CT cerebral perfusion imaging,such as cerebral blood flow (CBF),cerebral blood volume (CBV),the mean transition time (MTT) and the permeability surface (PS).With using Visual C ++ programming and CT scan images sequence obtained,the time-density curves of the brain tumor region were visualized.The more accurate hemodynamic parameters were calculated through an improved algorithm basing on the deconvolution and measuring method of the length,angle,area and other parameters.Conclusion:The quantitative analysis of feature parameter is of great benefit to clinical doctor in making timely diagnosis and treatment of brain tumor.
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We carried out a cross sectional study to analyze hemodynamic parameters of single-chamber ventricular pacemaker compared with dual-chamber pacemaker by using thoracic electrical bioimpedance monitoring method (Physio Flow™) - a novel simple non-invasive measurement. A total of 48 consecutive outpatients comprised of 27 single chamber pacemaker and 21 dual chamber were analyzed. We measured cardiac parameters: heart rate, stroke volume index, cardiac output index, estimated ejection fraction, end diastolic volume, early diastolic function ratio, thoracic fluid index, and systemic parameters: left cardiac work index and systemic vascular resistance index. Baseline characteristic and pacemaker indication were similar in both groups. Cardiac parameters assessment revealed no significant difference between single-chamber pacemaker and dual-chamber pacemaker in heart rate, stroke volume index, cardiac index, estimated ejection fraction, end-diastolic volume, thoracic fluid index. There was significantly higher early diastolic function ratio in single-chamber pacemaker compared to dual-chamber pacemaker: 92% (10.2-187.7%) vs. 100.6% (48.7-403.2%); p=0.006. Systemic parameters assessment revealed significantly higher left cardiac work index in single-chamber group than dual-chamber group 4.9 kg.m/m² (2.8-7.6 kg.m/m²) vs. 4.3 kg.m/m² (2.9-7.2 kg.m/m²); p=0.004. There was no significant difference on systemic vascular resistance in single-chamber compared to dual-chamber pacemaker. Single-chamber ventricular pacemaker provides similar stroke volume, cardiac output and left cardiac work, compared to dual-chamber pacemaker. A non-invasive hemodynamic measurement using thoracic electrical bioimpedance is feasible for permanent pacemaker outpatients.
Subject(s)
Biological Clocks , Pacemaker, ArtificialABSTRACT
PURPOSE: Mixed venous oxygen saturation (Smvo2) and other hemodynamic parameters are highly useful in the monitoring of critically ill patients, but the measurement of S m v o2 requires catheterization of the pulmonary artery. In contrast, central venous oxygen saturation (Scvo2) can be easily obtained with a central venous catheter, which is less invasive. To assess if Scvo2 could be a useful value in the treatment of critically ill patients, we evaluated the agreement and the relationship between Scvo2 and Smvo2. Furthermore, the correlations of Scvo2 with other additional parameters were investigated. METHODS: During 18 months, 83 patients in the intensive care unit (ICU) of Ajou university hospital were included. S c v o2, Smvo2, the cardiac index (CI), the oxygen extraction ratio (OER), the oxygen uptake (Vo2), and the oxygen delivery (Do2) were obtained by using a pulmonary artery catheter. RESULTS: There was a difference between Scvo2 and Smvo2 (76.32 +/- 7.86 vs 73.79 +/- 6.31, p < 0.001). The relationship between the two measures showed a meaningful correlation (r=0.700, p < 0.01). Scvo2 also had correlations with the CI (r =0.326, p < 0.05), the OER (r =-0.467, p < 0.01), the Vo2 (r =-0.393, p < 0.01), and the Do2 (r =0.422, p < 0.01). CONCLUSION: Although the Scvo2 value cannot replace the S m v o2 value, it shows a relation with Smvo2 and other parameters. Thus, Scvo2 is suggested as a hemodynamic value for use with critically ill patients.
Subject(s)
Humans , Catheterization , Catheters , Central Venous Catheters , Critical Illness , Hemodynamics , Intensive Care Units , Oxygen , Pulmonary ArteryABSTRACT
Objective To evaluate the diagnostic value of transcranial color duplex sonography for vertebrobasilar arterial insufficiency (VBI). Methods Transcranial color duplex sonography was performed on 30 healthy controls and 30 VBI patients confirmed clinically to examine the flow velocities and wave form parameters of the main supra and infra tentorial basal cerebral arteries. The anterior, middle, and posterior cerebral arteries on either side of the cranium and the vertebrobasilar system were observed using a 2.0 MHz transducer of a computed sonographic system. Results The vertebral artery system resistance index and pulsitive index were significantly higher in VBI patients than those in the controls ( P
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Objective To provide the normal hemodynamic parameters of uterine several arteries in reproductive women.Methods The hemodynamic parameters including peak systolic velocity(PSV),end diastolic velocity(EDV),resistance index(RI),pulsatility index(PI)and systolic/diastolic velocity ratio(S/D) of uterine artery(UTA),arcuate artery(AA),radial artery(RA)and spiral artery (SA) in 66 reproductive women were studied by transvaginal color Doppler(TVCD).The results were analyzed with T test.Results The flow of uterine several arteries in normal reproductive women was all detected well.From UTA to SA,parameters gradually decreased.In the secretory phase of menstrual cycle,the change of SA which EDV value was higher and RI value was lower was the most obviously.Conclusion The uterine hemodynamics in productive period is in close relalionship with menstrual cycle.We can predict the time of menstrual cycle according RI value of SA.