Neuroendoscopic technique, less invasive than conventional methods, has been recently introduced for the fenestration of the cystic lesions of the brain in pediatric neurosurgery. However, real-time monitoring is desirable for endoscopic surgery in patients with congenital malformations where anatomical structure are distorted, aberrant blood vessels are often found and, the intracranial volume goes on changing during the procedure.
Two cases of neuroendoscopic fenestration guided by color-coded sonography were presented. The first case was a 20-day-old boy who had interhemispheric multilocular arachnoid cysts. Neuroendoscopic fenestration of the cyst wall was performed at the age of 20 days and 5 months respectively. The second case was a fourteen-year-old boy with the cyst of cavum septi pellucidi and ventric lar dilatation. During endoscopic surgery color-coded sonography showed the direction of the endoscope, the position and motion of the tip of the endscope and the site of perforation performed. The blood vessels between or around cysts were also visualized. In both cases, cystic walls were perforated successfully and cysts were shrunken.
It was indicated that color-coded sonography was useful for real-time monitoring in neuroendoscopic surgery particularly in neonates and infants.

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We tried to estimate the usefulness of intraoperative ultrasonography in neurosurgical field.
The subjects were 20 patients with intracranial lesions and 9 patients with spinal lesions. The intraoperative ultrasound studies were performed after exposing the dura with a real-time ultrasound sector scanner and a 7 MHz probe (SSA-260A: Toshiba Medical Co, Ltd.) . Ultrasonography showed brain tumors as high intensity mass lesions. Major intracranial vessels were visualized well using color-coded sonography. Brain edema estimated by CT scan and MRI was not clearly identified. In Patients with spinal lesions, localizaton of lesions were identified clearly and operations were done with minimal myelotomy. The B-mode imaging is not so clear as CT scan and MRI. However, it is available intraoperatively and shows real-time localizations of vessels and intracranial or spinal lesions. This intraoperative sonography is beneficial for safe surgery of intracranial and spinal lesions.

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In order to investigate the mechanism of cervical bruits which developed at the origin of the internal carotid arteries degrees of stenosis and blood velocity of the carotid arteries were studied. Materials were 521 arteries in 273 patients who were admitted for cerebral infarction.
Angiography was performed with 140 arteries. A bruit was detected in 2.2% of the normal group, 31.3% of the group with stenosis of 49% or less, 14.3% of the group with stenosis of 50-99%, and 16.7% of the group with occlusion.
In carotid ultrasonography, stenotic lesions was measured in B-mode and color doppler, blood velocity in puls doppler. Carotid ultrasongraphy was performed with 406 arteries.
A bruit was detected in 25.8% of the non-stenosis group, 39.4% of the stenosis without turbulence group, 75.0% of the stenosis with turbulence group, and 33.3% of the occlusion group. The results demonstrated that turbulence played a role in the development of a bruit. Arteries with bruit among the non-stenosis group, increased systolic velocity and differences between systolic and diastolic may correlate with the etiology of the bruits.

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The usefulness of Doppler sonography (DS) of the ophthalmic artery (OA) for the screening of occlusive internal carotid artery (ICA) diseases was discussed and analyzed. [Materials and Methods] Forty-seven cases with abnormal findings of DS of OA were examined by cerebral angiography. There were 36 males and 11 females, Mean age was 59 years. Doppler sonography of the OA was performed using Bidirectional Doppler D-10. [Results] 1) The abnormal DS findings were classified into two patterns; an arch stenosis pattern (SP) in 21 cases and a reversed flow pattern (RP) in 26 cases. 2) On the angiograpm, SP cases showed ICA stenosis or occlusion with collateral flow through the intracranial vessels, while RP showed occlusive ICA lesions with collateral flow through the extracranial vessels. 3) In the most of the SP cases, the OA was filled normogradely, and in the most of the RP cases, the OA was filled retrogradely. [Conclusion] DS of the OA is a non-invasive examination and shows good correlation with the angiographical findings of ICA and OA. Therefore, DS of the OA could be useful for the screening of ischemic internal carotid artery diseases.

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