The main aims of public health care are the prevention of cardiovascular disease and management of malignant disease. For the prevention of cardiovascular disease, risk factor control such as treatment of hypertension, hyperlipidemia, diabetes mellitus, and cessation of tobacco smoking are important. In Japan, financial support for extra health care checks aimed at the prevention of cardiovascular disease was started in April 2001. Carotid and cardiac ultrasonography were nominated as second-line examinations in patients with high blood pressure, high blood lipid levels, high blood sugar, and obesity.
Carotid atherosclerosis is known to be a useful indicator of ischemic cerebrovascular disease and ischemic heart disease. Noninvasive ultrasonic examination is a standard method for assessment of carotid artery disease. In this paper, I explain the present consensus for evaluating carotid atherosclerosis by ultrasonography in line with the Japanese guidelines. If a patient is found to have obvious carotid atherosclerosis, it is necessary to conduct more intensive control of the risk factors. More severe control is needed for reduction of blood pressure and cholesterol, recovery of insulin resistance, and so on.

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As the significance of the HITS count in patients undergoing heart valve replacement is still unknown, we compared the normal functioning of the St. Jude Medical (SJM) valve and the Advance The Standard (ATS) valve in the aortic position to evaluate any effects of differences in valve structure on the HITS count.
Fifty-seven patients after aortic valve replacement (40 with the SJM and 17 with the ATS) were examined by transcranial Doppler (TCD) monitoring for 15min. All the patients showed normal prosthetic valve function by echocardiography and cineradiography, and had no history of stroke or carotid stenosis. There were 42 males and 15 females with a mean age of 58.2 years. The mean duration after surgery was significantly longer in patients with the SJM (77.3 months) than in those with the ATS (39.3 months) .
The average HITS count was 1.55 per 15 min for the SJM and 0.59 per 15 min for the ATS, although the difference was not significant. These results suggest that the difference in the hinge structure and opening angle between the two valves may cause a slight difference in the HITS count. Therefore, in patients with valve replacement, the type of prosthesis should be considered when examining TCD.

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Thirty-six patients who had undergone carotid endarterectomy (CEA) were evaluated to determine the effect of CEA on ophthalmic artery flow.
The internal carotid artery in all the patients was more than 50% stenotic at its origin. The ophthalmic artery ipsilateral to the CEA was evaluated by color Doppler flow imaging before surgery and then at one week, one month, and three months after surgery.
(1) Before CEA, 10 patients showed reversed ophthalmic artery flow. In the other 26 patients with antegrade ophthalmic artery flow, the average peak systolic flow velocity was 0.17 m/s. (2) At one week after CEA, the reversed ophthalmic artery flow was resolved in every patient. The average peak systolic flow velocity in the patients with preoperative antegrade flow rose significantly to 0.26m/s (p<0.05) . (3) At one month and three months after CEA, the average peak systolic flow velocities showed no significant change compared to the value at one week after CEA.
CEA corrected the reversed ophthalmic artery flow and increased the peak systolic flow velocity of the ipsilateral ophthalmic artery immediately after surgery.

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A new mode of sonography termed B-flow has been developed to provide direct visualization of blood streams. The present study was done to evaluate flow abnormality in patients with cervical carotid artery stenosis after carotid endarterectomy using B-flow sonography. Eight consecutive patients with cervical carotid artery stenosis underwent carotid artery B-flow sonography after the treatment using a LOGIQ 700 unit (General Electric, Yokogawa Medical Systems; Tokyo, Japan) equipped with a wide-bandwidth (5-10 MHz) linear-array transducer. We were able to detect the blood flow and plaque morphology in all cases simultaneously. Using B-flow, all flow patterns were visualized clearly without blooming, as is often the case in color flow imaging and power Doppler imaging. The intima-media complex was visualized clearly 4 weeks after the carotid endarterectomy in all cases. Turbulent flow which was not evident in the DSA was visualized at the proximal edge postoperatively in 5 cases. This was significantly decreased 12 weeks later, and the flow patterns were normalized. Reverse flow and stasis of the blood stream at the carotid bulb were observed in one case, where a thrombus was detected at the endarterectomized site. Detection and evaluation of postoperative blood flow patterns are important for evaluating thrombus formation and intimal hyperplasia after carotid endarterectomy.

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We studied 1, 282 persons (age range: 29 to 83 years; mean age ± S.D: 45.8± 14.7 years; male: female ratio: 678: 604) who underwent routine health check-ups at our hospital for detection of asymptomatic brain diseases. According to the presence or absence of arteriosclerosis (AS) on MRA, the subjects were divided into an AS group (564 subiects) and a non-AS group (718 subjects), and then (1) mean age, (2) systemic blood pressure, including systolic blood, pressure (SBP), diastolic blood pressure (DBP), and pulse pressure (PP), and (3) mean blood flow velocity (mFV) and PI value (PI) obtained at the common carotid artery (CA) and middle cerebral artery (MCA) using transcranial Doppler ultrasonography (TC2-64; Rikoh Shoji) were compared between the two groups.
(1) The mean age in the AS group (66.8±8.9 years) was significantly higher than in the non-AS group (47.9±13.4 years) (p<0.02) . (2) The mean values of SBP, DBP, and PP were found to be 156.5 ± 9.8 mmHg, 77.5 ± 10.2mmHg, and 67.5 ± 7.4mmHg, respectively, in the AS group, and 132.25 ± 12.6mmHg, 72.5 ± 7.8mmHg, and 47.5 ± 8.0mmHg, respectively, in the non-AS group, revealing significantly higher SPB and PP values in the AS group (p<0.05 and p<0.02, respectively) . (3) mFV at the CA and MCA did not differ significantly between the AS and non-AS groups. PI at the CA and MCA was determined be 1.01 ± 0.28 and 0.81 ± 0.32, respectively, in the AS group, and 0.67 ± 0.19 and 0.58 ± 0.24, respectively, in the non-AS group, revealing significantly higher PI in the AS group (p<0.02, p<0.05) . It was noteworthy that all subjects having a PI of 1.0 or higher were included in the AS group.

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Cerebral embolism is one of the major complications associated with hepatic arterial chemotherapy using percutaneous catheter placement with an implantable port. We report a case of “basilar top syndrome” after insertion of a heparin-coated catheter from the left subclavian artery for treatment of multiple liver metastases.
A 47-year-old woman with hepatic metastases from sigmoid colon cancer was treated by hepatic artery infusion of 5-FU. The patient developed neurologic signs and symptoms including disorientation, aphasia and motor weakness in her right hand on July 4th, 2000. CT scan detected small low-density areas in the bilateral thalamus. B-mode (color duplex) ultrasonography displayed the catheter in the left subclavian artery. The catheter showed to-and-fro movement pulsatively synchronized with her respiration and heartbeat. Fast Fourier Doppler images detected the sounds of the catheter beating against the vessel wall. The patient recovered after treatment with low-dose heparin and aspirin.
In this case, it is possible that the thrombus migrated into the left vertebral artery from the surface of the catheter and/or the atheromatous plaque in the subclavian artery. B-mode ultrasonography was useful for diagnosing the etiology of the thrombus.

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I review the history of my neurosonological work and my personal communication with many members of JAN.
My first project was to apply a miniature Doppler probe to a cerebral aneurysm to investigate intra-aneurysmal hemodynamics, and the data were published in 1974. Power spectrum analysis showed three peaks of wave frequency in the aneurysmal turbulence. Even today, the intraoperative Doppler flow method is very useful in the surgical treatment of aneurysms and AVMs, facilitating correct clipping of the aneurysm neck and total excision of AVM.
Secondly, the transcranial Doppler (TCD) method was used for evaluating the severity of vasospasm (VS) in patients with ruptured aneurysm. TCD findings indicated a clear relationship between increasing blood flow velocity and development of VS, and allowed prediction of VS before the appearance of ischemic neurological symptoms.
Thirdly, B-mode ultrasonography was applied to patients with carotid occlusive disease. The correlation between B-mode Doppler and angiographical data was good. Overall accuracy was about 90%, permitting the identification of several characteristics of plaque before carotid endarterectomy.
Finally, I give my opinion on the history and future of neurosonology with reference to the papers presented at previous meetings of NRGW in Taipei in 1999, and in Lisbon in 2001.

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