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Combined operation of coronary artery bypass grafting (CABG) and carotid endarterectomy (CEA) was performed for a 77-year-old man who had triple vessel with left main trunk coronary artery disease and severe left carotid artery stenosis. The left internal thoracic artery and three saphenous vein grafts were bypassed with a single proximal anastomosis as CABG, and CEA was done with vein patch plasty under selective cerebral perfusion using a cardiopulmonary bypass circuit. He recovered without complications and did not require no homologous blood transfusion. We consider elderly CABG patients high risk to be at arteriosclerotic complications, so careful management is needed for individual cases.

Superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis is a common procedure for neurosurgeons. The surgery necessarily requires accurate and speedy manipulation of microscope, for which a specific training is needed. Unexpected bypass occlusion sometimes happen during surgery. Generally, conventional interrupted or continuous suture has been used for vascular anastomosis, despite various ideas have been attempted in the other surgery fields. We propose a horizontal mattress suture technique for intracranial microvascular bypass surgery. This is the first report ever published on intracranial vascular anastomosis. We had four patients of STA-MCA bypass surgery with “mattress anastomosis” from March to May of 2012. During the procedure, there was no bypass occlusion and good patency was confirmed in all cases. Intimae of the recipient and the donor blood vessel contact each other precisely with this technique. Although a long-term assessment of patency is needed, it is useful for the intracranial bypass surgery.

The case is presented of a 45-year-old man who suffered from a sudden attack of unconsciousness with right hemiplegia and later developed a spastic hemiparesis accompanied by involuntary movement of the right upper limb. CT scan revealed an old putaminal hemorrhage and almost intact thalamus, but neural noise recordings during the stereotactic thalamotomy of this case showed marked decrease of the neural activity in the thalamus suggesting some functional changes.

In the course of stereotactic thalamotomy, the neural noise level of subcortical structures was estimated quantitatively with the aid of two semimicro-electrodes. The neural noise showed several characteristic features in terms of its amplitude and discharge pattern so that it was correlated with the possible anatomical substrate, thus providing the functional anatomy of the subcortical structures. The study on sagittal plane revealed a systematic difference of the noise level between VL and Vim-Vc that could be explained by the different cell size in respective nucleus. Several exceptional cases were also presented, emphasizing the neural noise study in stereotactic surgery.

An attempt has been made to visualize beforehand a brain section through which an electrode would pass to reach the target point in stereotactic thalamotomy for the treatment of tremor. On the basis of several craniometric measurements of a plain craniogram (lateral view), the level of the intercommissural line could be approximately estimated and a tentative target point set on the craniogram. Then, a line is drawn to connect this target point and the bregma. Extrapolating this line, an angle between the Reid baseline and this line could be measured in order to transfer the line to the scalp. With the aid of a GE scanner (GE-CT/T-X2), several 5-mm thick sections are made parallel to this line including the tentative target point. Among these images of CT scan thus made, referring to the foramen of Monro and the aqueduct (either of which might be visualized) one of the sections would be chosen as a tentative plane through which the electrode would pass. On the operation day, a burr hole should be made on or near the line used for CT scanning and drawn on the scalp, so the electrode tract will coincide with the CT scan image. GE scan images are clear enough to estimate the range of gray matter, white matter, caudate nucleus and thalamus. The neural activities of the deep structures recorded during the operation by stepping displacement of the electrode are correlated with this CT scan image. So far, the coincidence of both findings are satisfactory and of great value in this kind of blind operation.

In the course of stereotaxic thalamotomy by Leksell's open system in 20 cases of abnormal movement, recording and stimulation of the subcortical structures have been performed by means of two semimicro-electrodes introduced parallel to the frontal plane. Taking advantage of simultaneous recording and electrical stimulation through these two electrodes, several critical points in the caudate nucleus and thalamus have been clearly delineated. Thus in each individual case an outline of the thalamic configuration in the frontal plane could be obtained, so that the final therapeutic lesion was placed with good precision at the lower-most border of VL or Vim nucleus. It has been shown that the physiologically determined minimum lesion resulted in satisfactory alleviation of the abnormal movements without notable untoward effects.

✓ The authors report the results of a long-term follow-up study of the effects of the physiologically defined selective VIM (nucleus ventralis intermedius)-thalamotomy on tremor of Parkinson's disease in 27 patients and essential tremor in 16 patients. The follow-up period ranged from 3.25 to 10 years (mean 6.58 years). In 43 patients a total of 50 operations (including four bilateral operations and three reoperations) were carried out. The early (2 to 4 weeks after surgery) and late effects on the tremors were determined clinically and electromyographically. Fourteen parkinsonian cases were treated with minimal lesions (about 40 cu mm). Their late results were very similar to the early results: in 10, the tremors were completely abolished, three had a slight residual tremor, and one underwent reoperation 3 months after the first surgery. Eleven essential tremor cases were treated with minimal lesions. Six of these tremors were completely abolished, four patients had slight residual tremors, and one patient with a recurrence underwent reoperation 2 years after the initial surgery. In these 23 successful operations with minimal lesions (excluding two cases with reoperation), the tremor was abolished without discernible long-lasting side effects. The other 23 operations on 16 patients with Parkinson's disease (including one reoperation) and on seven with essential tremor (one of whom also had a minimal lesion on the other side) involved relatively large lesions. In this group, the surgery was successful in almost every case. It was concluded that radiographically and physiologically monitored selective VIM-thalamotomy for parkinsonian and essential tremor is effective even when lesioning is minimal. Moreover, the beneficial effect is maintained over a long period of time.

A case of primary cerebral ganglioneuroblastoma of the anterior skull base was reported. The patient, a 19-year-old male, suffered from visual disturbance and fatigability. Obesity, hypogonadism, disturbance of visual acuity, visual field defect, and bilateral choked discs were revealed and moderate panhypopituitarism was found. Plain craniograms showed signs of increased intracranial pressure and demineralization of the anterior skull base. Left carotid angiograms showed a left to right displacement of the anterior cerebral artery and an oval vascular stain in the left frontal region. EEG revealed a polyphasic slow wave focus in the left frontal region. Partial removal of the tumor was performed and Linac therapy with a tumor dose of 4, 000 rads was given. The histological dignosis was ganglioneuroblastoma, which showed small, uniform, spherical cells with abundant nuclear chromatin and large cells with some processes and Nissl granules. At follow-up studies 3, 5, and 6 years after the operation, only a slight decrease of visual acuity was noted and no enlargement of the tumor was found in CT scans or cerebral angiograms. A histological maturation of this tumor may have occurred.

In 51 cases (6 cases with bilateral operations) with various kinds of tremor, stereotaxic ventralis intermedius (Vim) thalamotomies were performed using Leksell's apparatus and the results of operation evaluated. Several characteristics of the tremor, including clinical features and EMG, were correlated with the assumed location and volume of the coagulative lesion. In 54 of the 57 operations, the thalamic Vim nucleus was identified physiologically and a therapeutic lesion placed at a site that included the Vim neurons. In all these cases, except one in which the lesion was estimated to be too small, tremor was immediately abolished by a relatively small lesion. The estimated volume of the lesion was about 40 to 200 mm3 and the effect persisted over a long follow-up period (maximum ten years). The size of the lesion that was necessary apparently depended on several features of the tremor. A larger lesion was required in cases of movement type tremor, tremor with a low rate (less than 4 Hz), tremor of high amplitude (more than 600 microV), and tremor involving proximal muscles or with a wide distribution. Tremor following a cerebrovascular lesion and post-traumatic tremor were characterized by coarse oscillation (high amplitude and low frequency) involving proximal muscles. A relatively larger coagulative lesion was therefore necessary to relieve this type of tremor. In contrast, parkinsonian and essential tremor were usually of low amplitude and distal in distribution. For the relief of such tremor, the lesion could be very small: if aided by electrophysiological methods to identify Vim neurons, the minimal effective volume of the lesion was estimated as about 40 mm3 and restricted to the Vim nucleus. Based on these results, the importance of the Vim nucleus in tremor mechanisms is discussed.

6 cases with tremor-athetotic type cerebral palsy and 2 cases with moderate dystonia-tremor type cerebral palsy were treated by selective stereotactic thalamotomy. In the former group, postural-movement type tremor in the upper limb gradually progressed with age while athetosis remained unchanged. In the latter group, dystonia in the truncal muscles predominated over the irregular tremulous movement of the upper limbs. In all cases, the intelligence was almost normal. Stereotactic selective thalamotomy (Vim for tremor athetosis, VL-Vim for dystonia tremor) was performed under local anesthesia with the aid of radiological and neurophysiological control methods. The results of the operations were satisfactory in regard to the tremor relief and concomitant improvement of motor performances in most of the cases. Stereotactic treatment might be an effective way to make possible a one-step progress in these handicapped cases. The importance of postoperative physical therapy is also emphasized.