Diabetes Mellitus is an important factor in aggravation of atherosclerosis. Common carotid arterial wall properties and hemodynamics in healthy (H) and in diabetes mellitus (DM) groups were measured by an ultrasonic quantitative flow measurement system. Each group was divided into 3 classes according to age, class 1: 45-54, class 2: 55-64 and class 3: 65-74 y.o. Wall properties examined were vessel diameter (D) and stiffness parameter (β), while hemodyamics examined were maximum blood velocity (Vbmax), blood flow volume (Qb), and carotid and cerebral vascular resistance (Zo) . These indices, measured before and after a 5-year interval, were compared. Statistical analysis: the results were analyzed using student-t test; p-value less than 5% was defined as significant (*) . Results obtained were as follows: The increases in D (mean value) were -1.1, 4.3, 0.2% in the H group and 6.3*, 5.2*, 4.5*% in the DM group in classes 1, 2 and 3 respectively. The increases in mean/βwere 2.9, 3. 0, 9.1% in the H and 23.7*, 13.0 24.3*% in the DM group. Vbmax decreased -7.4, 6.9, -0.6% in the H group and 18.6*, 9.3*, 14.3*% in the DM group. Qb decreased 0.5, -3.1, 0.6% in the H group and 3.4, 2.0, 6.8% in the DM group. The changes in each index after 5 years were larger and more significant in the DM group as compared with the H group. In conclusion, atherosclerosis of the carotid and cerebral arteries would aggravate more rapidly in the DM group than in H group from middle age together with dilatation, stiffening and hemodynamic disorders.
We recorded the change of blood flow velocity before, during and after hyperventilation (HV) in bilateral Internal Carotid Arteries (ICA) and Vertebral Arteries (VA) simultaneously and continuously of 4 healthy males. The MULTI-DOPPLER-SYSTEM (HAYASHI ELECTRIC, Inc. Kawasaki, JAPAN) and four ultrasonic probes fixed by a cervical brace (KAWAMURA ARTIFICIAL LIMB, Inc.Osaka, JAPAN) were used to obtain data. We calculated Averaged Maximum Velocity (AMV) for every heart beat as the Index of blood flow and visualized them in 4 subjects. AMV repeatedly increased and decreased every several seconds. HV induced a statistically significant AMY decrease. The AMY interrelations between any two vessels in each subject were all statistically significant. The coefficients of correlation were largest during HV and smallest before HV.
We performed 78 color Doppler examinations to demonstrate intracranial vasculature in 61 infants; 30 cases with normal and 19 with abnormal central nervous system anatomy. Developmental abnormalities such as hydrocephalus, hydranencephaly, holoprosencephaly, absent corpus callosum, and Dandy-Walker syndrome were demonstrated. Serial scans were obtained in sagittal, coronal, and axial plains. Most of the major intracranial arteries and veins could be clearly demonstrated in real-time. In patients with hydrocephalus, color Doppler imaging demonstrated a widely streched and elevated sweep of the anterior cerebral arteries, straightening of the middle cerebral arteries by the enlarged ventricles. The internal cerebral veins, great cerebral vein, straight sinus were straighted and displaced posteriorly and inferiorly. In infants with absent corpus callosum, anterior cerebral arteries and their branches appeared to be wavy. However, in patients with developmental abnormalities, visualizations of the vasculature were relatively poor. In conclusion, the color Doppler examination is a useful and practical method of imaging of cerebral vessels in infants, because of its non-invasiveness and portability.
Using Doppler color flow mapping, intracranial hemodynamics were evaluated for 65 normal neonates as well as 7 neonates with symptomatic patent ductus arteriosus (sPDA) . The pre-ejection period (PEP), ratio of PEP to ejection time (PEP/ET) in the ascending aorta, as well as both the middle cerebral artery (MCA) and the basilar artery (BA) were measured. For normal neonates, there were no significant postnatal changes in the PEP and the PEP/ET of the aorta, MCA and BA. However, for neonates with sPDA, the PEP had shortened and the PEP/ET had decreased in the aorta, MCA and BA as compared to those of normal neonates. The time difference between the PEP of the aorta and that of the cerebral artery (EPEP) were also calculated. The OPEP of both MCA and BA were considered to have been affected by the characteristics of the vessel between the aorta and the cerebral artery. In normal neonates, the ΔPPEP of BA showed no significant postnatal changes. However, the ΔPEP of MCA shortened significantly after birth (p<0.05) .
Flow patterns of the velocity measured by transcranial Doppler (TCD) were compared with the changes of intracranial pressure (ICP) in patient with subarachnoid hemorrhage and severe head trauma in our department. The flow velocities in the middle cerebral artery or internal carotid atrery were measured using TCD in 12 patients who developed brain death due to progressive increased ICP. Our studies demonstrated that flow patterns were influenced in response to increased ICP. The flow pattern showed a low resistance high flow profile in physiological state. On the other hand, TCD demonstrated a high resistance low flow in reply to increase in ICP.In the stage of marked increase in ICP, TCD revealed progressive reduction of mean flow velocity and diastric negative flow. Finally an oscillating flow pattern or spiky systolic flow pattern was estimated by TCD in brain death patients. TCD is beneficial to evaluate the arrest of intracranial circulation in brain death.