The aim of this study was to evaluate the use of intraoperative navigation in combination with ultrasonography. Between December 2008 and June 2009, 19 patients with brain mass lesions underwent surgery with the aid of a TREON navigation system (Medtronic) along with SonoSite ultrasonography. The ultrasonographic image was directly integrated into the navigation system, and the findings were compared. Intraoperative ultrasonography provided immediate ongoing information about the anatomy and pathological lesions. Image overlay of the sonographic display and corresponding topographic scans using this system was able to provide an estimate of brain shift. Thus, Doppler ultrasonography demonstrated flow signals from the surrounding vessels. Using this type of assistance, gross total removal of the lesion was performed in all cases. Intraoperative ultrasonography supported by a navigation system resulted in satisfactory removal of the lesions.

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One of the most problematic complications of STA-MCA bypass is cerebral hyperperfusion (CHP). We studied the benefit of intraoperative mFV measurement for prediction of CHP after bypass surgery. A total of g patients with occlusive cerebrovascular disease (6 males and 3 females, mean age 61 years) underwent intraoperative measurement of STA mFV. In 2 patients, the mFV showed a significant 9-fold increase compared to the preoperative mFV, and postoperative SPECT also showed asymptomatic CHP on day 3. These results suggest the benefit of measurement of STA mFV for prediction of CHP.

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Background and Objectives: Detection and evaluation of carotid plaque using conventional two-dimensional (2D) carotid ultrasonography is not sufficient for evaluating the three-dimensional extent of the plaque. We have therefore been applying the latest technique of three-dimensional (3D) ultrasonography to observe the three-dimensional aspects of carotid plaque. The present study was performed to compare morphological changes in plaque before and during treatment with fluvastatin using 3D ultrasonography.
Methods: The subjects were 13 patients with carotid plaque (M:F = 9:4,65 ± 11 years old). Serum LDL cholesterol levels in these patients exceeded 140mg/dl. 3D plaque images were acquired using a VOLUSON 730 expert (GE Healthcare) with a 3D/4D probe. Volume of plaque, axial plaque area and maximum intima-media thickness (Max-IMT) were measured and compared every 3 months during administration of fluvastatin at 20mg/day.
Results: Carotid plaque volume (0.509 ± 0.576cm³) was reduced at 3 months after the start of fluvastatin administration (0.426 ± O.537cm³ p = 0.001). Axial plaque area (0.251 ± 0.145cm²) was reduced at g months (0.229 ± 0.158cm², p = 0.039), and Max-IMT (2.649 ± 1.036mm) was reduced at 12 months (2.469 ± 0.997mm, p=0.010).
Conclusions: 3D ultrasonography is useful for monitoring the three-dimensional aspects of carotid plaque with high reliability. The present findings indicate that fluvastatin improves the morphology of atherosclerotic carotid plaque by reducing its volume.

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The aim of this study was to investigate the usefulness of acceleration time (AcT) determined by sonography for evaluation of severe stenosis in the internal carotid artery (iCA). We evaluated 127 ICAs and common carotid arteries (CCAs). Linear- and convex-array probes were used for sonographic assessment, and the peak systolic flow velocity (PSV) at the carotid bulb was evaluated by the pulsed Doppler method. The linear-array probe was set in the CCA 2cm above the carotid sinus, and the convex-array probe was set in the ICA 3cm above its origin to measure the Doppler waveform. The Act ratio was calculated as ICA/AcT of the ipsilateral CCA and correlated with the PSV. Simple regression analysis and the receiver operating characteristic curve were used to examine the relationship between the AcT ratio and PSV. There was a significant relationship between the PSV and AcT ratio. Based on the receiver operating characteristic curve, the sensitivity and specificity of the AcT ratio using a cutoff level of 2.0 were 90.0% and 96.6%, respectively, for diagnosis of a PSV exceeding 200cm/s. These results suggest that an AcT ratio of 2.0 reflects a degree of stenosis exceeding 70%.

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We report an 81-year-old man who suddenly felt weakness of the right upper and lower extremities. He was admitted to our hospital within 1 hour after onset Neurological examination revealed consciousness disturbance and right hemiparesis. The National Institutes of Health Stroke Scale (hflHSS) score in the emergency room was 7. As the neurological impairment was completely resolved in the emergency room, we diagnosed the patient as having a transient ischemic attack. However, 5 hours after admission, aphasia and right hemiparesis recurred with a NIHSS score of 5, and MR angiography demonstrated occlusion of the left internal carotid artery (ICA) corresponding to hyper-intense lesions in the left frontal lobe on diffiasion-weighted imaging. We treated the patient with intravenous tissue plasminogen activator (IV t-PA) while monitoring the left ICA using carotid ultrasonography. Initially, the blood flow velocity in the left ICA showed an occluded pattern, and then 30 minutes after starting IV t-PA, the left ICA demonstrated diastolic flow velocity. After several minutes, the flow pattern in the left ICA changed to a normal one. The neurological manifestations showed dramatic improvement, with a NfflSS score of 1. Carotid duplex ultrasonography appears to be a promising tool for observation of recanalization after ICA occlusion.

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