Substantia nigra (SN) hyperechogenicity can be demonstrated by transcranial ultrasonography (TCS) as a typical, stable finding in about 90% of patients with Parkinson's disease (PD). SN hyperechogenicity is also observable in about 10% of normal healthy controls, irrespective of age. TCS of the SN is likely to be useful for the differential diagnosis of PD and related disorders, because SN hyperechogenicity is observed less frequently in patients with atypical parkinsonism, such as multiple system atrophy and progressive supranuclear palsy. Unfortunately, in Japanese patients, the rate of successful recording of the SN by TCS decreases prominently with advancing age. particularly in females. The cause of SN hyperechogenicity remains undetermined. However, there is a hypothetical concept that SN hyperechogenicity is a biomarker of vulnerability of the nigrostriatal dopaminergic system associated with increased iron levels in the SN. We propose that TCS is a useful tool for not only the clinical evaluation of patients with PD or related disorders, but also the preclinical evaluation of subjects at risk of developing PD. We hope that this brief review will contribute to a better understanding of the potential of TCS of the SN in patients with PD.

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Power Doppler imaging (PDI) is a useful modality for identifying slow-flow and small vessels. The present study was an attempt to evaluate the peripheral cerebral circulation using PDI and pulsed Doppler ultrasonography (PD) . The peripheral circulation was assessed at the lenticulostriate artery (LSA) in 25 normal-term neonates and six preterm neonates (gestational age 28-33 weeks) without neurological symptoms. In all subjects, PDI clearly visualized the flow images in three components of the LSA in coronal sections through the anterior fontanel. The blood flow velocity was measured at three points in the most lateral component of the LSA by PD. In term and preterm neonates, the values of peak systolic velocity (SV) were almost lOcm/s, and those of the resistance index (RI) were approximately 0. 5 on the first postnatal day at the three points in the LSA. The values of sv and RI at the LSA were chronologically steady in term and preterm neonates during the seven days after birth. Case studies of five pathological neonates suggested that the deviation of RI values in the LSA on the first postnatal day was related to severe neurological sequelae. PDI can be used successfully to image and map the LSA and contributes to confirmation of steady peripheral perfusion in the basal ganglia supplied by the LSA.

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Purpose : Temporal arteritis (TA) involves granulomatous inflammation with giant cells in arteries of the external carotid system. Prompt diagnosis and treatment are important to avoid irreversible neurological damage. We examined the temporal arteries in patients with TA using ultrasonography and evaluated the clinical usefulness of this modality for diagnosis of TA.
Subject : The subjects comprised six patients (one man. five women) diagnosed as having TA according to the criteria of the American College of Rheumatology. The patients were studied periodically using ultrasonography after steroid treatment.
Results : The long-axis view of the temporal artery showed narrowing of blood vessel diameter. hyperplasia of intima-media thickness (IMT), segmetital dilatation, or intravascular occlusion. Short-axis imaging revealed a hypoechoic halo around the temporal artery in all cases. Serial observations of the temporal artery showed disappearance of the hypoechoic halo after two or three months of steroid therapy in all cases. After six months. four patients showed normal results of temporal artery ultrasonography.
Discussion and Conclusion : A hypoechoic halo around the temporal artery on ultrasonography represents a characteristic finding of TA. Ultrasonography is a useful. non-invasive tool for diagnosis of TA and evaluating the efficacy of treatment.

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A portable ultrasound scanner and a small transducer with a straight. untapered head were used to observe intracranial lesion at the burr-hole surgery. After opening a standard burr-hole, the transducer was inserted to the burr-hole and intracranial lesion was examined. Common indications for this technique included guidance for placement of catheters and ventriculoperitoneal shunts, localization of masses, guidance for aspiration of cysts and other fluid collections, and confirmations of removal tumors. Intraoperative ultrasonography provided immediate ongoing information about the anatomy and pathological lesion. Distance and trajectory to the best location for the catheter were determined and the catheter was inserted with ultrasound monitoring. No procedure related complication was noted and pitfall was minimal. Furthermore, result of postoperative CT scan was consistent with findings of intraoperative ultrasonography. In conclusion, ultrasonography using burr-hole transducer has proved useful in a variety of procedures during burr-hole operation.

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Purpose : The mean flow velocity of the middle cerebral artery (MCA-MFV) on transcranial color-coded sonography (TCCS) and blood pressure was monitored after carotid stenting (CAS) and carotid endarterectomy (CEA),and we investigated the correlation between MCA-MFV and mean blood pressure.
Subjects and methods : Twenty patients who underwent CAS and CEA were studied. MCA-MFV using TCCS and blood pressure were monitored daily.
Results : Two patients developed cerebral hyperperfusion syndrome (CHS). In CHS cases, the ipsilateral MCA-MFV showed a sudden 1. 7-fold increase in the early postoperative phase. and the ipsilateral MCA-MFV was correlated with mean blood pressure until l week (case 1) or 2 weeks (case 2) after surgery. Ipsilateral MCA-MFV and mean blood pressure then showed no correlation at 2 weeks (case 1) or 3 weeks (case 2) after surgery. In non-CHS cases, the ipsilateral MCA-MFV was stable and blood pressure-independent. In both CHS and non-CHS cases. contralateral MCA-MFV was stable and blood pressure-independent.
Discussion : Changes in ipsilateral MCA-MFV and blood pressure appear to be related to transient dysfunction of auto-regulation. Strict blood pressure management should be maintained until the ipsilateral MCA-MFV becomes stable and independent of blood pressure.
Conclusions : In the treatment of CHS, serial TCCS and blood pressure monitoring after CAS and CEA may be useful for management of blood pressure.

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Randomized trials have established that treatment with statin (3-hydroxy-3-methylglutaryl-CoA reductase inhibitor) can reduce the progression of vulnerable carotid plaque. However, detection and evaluation of carotid plaque using conventional 2D (two-dimensional) carotid ultrasonography is not sufficient to evaluate the three-dimensional extent of carotid plaque. We experienced a case of carotid plaque in which the use of statin and 3D (three-dimensional) ultrasonography was proved to be superior to the conventional 2D method for evaluation and quantitative measurement of carotid plaque with high reliability.
The patient was a 43-year-old man with hypertension. atrial fibrillation and a history oflacunar infarction. He was referred to our hospital because of left carotid bruit. 3D ultrasonography revealed vulnerable plaque in the left common carotid artery. The volume of the plaque was calculated to be 0.31mm³.Huvastatin, 20 mg daily, was started.Three months later. the plaque volume had diminished to 0.12 mm³ and the 2D characteristics of the plaque were improved. although the serum LDL cholesterol level was not changed before (157mg/dL) and after (152mg/dl) fluvastatin. These data suggest that 3D ultrasonography is a valid and useful tool that is superior to the conventional 2D method for evaluation and quantitative measurement of carotid plaque with high reliability.
The present study indicates that fluvastatin improves the morphology of atherosclerotic carotid plaque. reducing its volume within 3 months.

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