We evaluated regional cerebral blood flow (rCBF) during vasospasm after subarachnoid haemorrhage (SAH) using automated voxel-based analysis of brain perfusion single-photon emission computed tomography (SPECT).

The brain is frequently affected by the spread of lung cancer, and haematogenous metastasis is a common route to brain metastasis. We therefore developed an isogenic brain metastasis model of lung cancer to use the Lewis lung carcinoma cell line and analysed dynamics of neoplastic cells after extravasation. Histological analysis revealed two characteristic patterns: metastatic foci exhibiting an angiocentric pattern were designated ‘perivascular proliferations’; neoplastic cells infiltrating the brain parenchyma were designated ‘invasive proliferations’. Electron microscopic observation of perivascular proliferations showed that neoplastic cells were confined to the perivascular space. In invasive proliferations, however, fragments of collagen fibre were observed in the gaps between neoplastic cells, indicating that the neoplastic cells had disintegrated the pia‐glial membrane. We analysed the expressions of matrix metalloproteinase‐2 (MMP‐2) and MMP‐9 by using both immunohistochemical analysis and real‐time polymerase chain reaction analysis. MMP‐2 expression was significantly higher in invasive proliferations. MMP‐9 expression was significantly higher in day 7, but there was no significant difference in day 11. The pia‐glial membrane and perivascular space are the barriers that neoplastic cells must overcome to infiltrate the brain. In conclusion, our findings suggest that brain metastasis requires two distinct processes.

We describe a case of giant cervical internal carotid aneurysm successfully treated by endovascular trapping. A 57-year-old woman with a history of maxillary contusion seven years before presented with pharyngeal discomfort during swallowing. MRI revealed a 4 cm mass in the right parapharyngeal space. A common carotid angiogram revealed a giant aneurysm with a wide neck originating from the cervical internal carotid artery, kinking of the internal carotid artery was noted at a point distal to the carotid bifurcation. Analysis of cerebral blood flow by SPECT during a balloon occlusion test showed no hypoperfusion areas, and the patient underwent endovascular trapping. There were no neurological or other complications after the procedure. A follow-up MRI revealed complete thrombosis of the aneurysm. Our results show that endovascular trapping for pseudoaneurysm of the cervical internal carotid artery can be a reliable and effective treatment in patients who tolerate a balloon occlusion test.

Proximal occlusion of the vertebral artery is regarded as a safe and effective method of treating aneurysms of the vertebral artery or the vertebrobasilar junction unsuitable for treatment by neck clipping. Complications known to develop after this procedure include ischemic lesions of the perforators and other areas. There are only a limited number of reports on early rupture of aneurysm following proximal occlusion of the vertebral artery for the treatment of unruptured aneurysm. We recently encountered a case of large aneurysm of the vertebral artery identified after detection of brainstem compression. This patient underwent proximal occlusion of the vertebral artery with a coil and developed a fatal rupture of the aneurysm ten days after proximal occlusion. The patient was a 72-year-old woman who had complained of dysphagia and unsteadiness for several years. An approximately 20 mm diameter aneurysm was detected in her left vertebral artery. She underwent endovascular treatment, that is, her left vertebral artery was occluded with coils at a point proximal to the aneurysm. Her initial post-procedure course was uneventful. However, she suddenly developed right-side hemiparesis nine days after procedure. At that time, CT scan suggested sudden thrombosis of the aneurysm. Right vertebral angiography revealed a small part of the aneurysm. She was treated conservatively. Ten days after the procedure, she suffered massive subarachnoid haemorrhage. Both the present case and past reports suggest that proximal occlusion of the vertebral artery is effective in treating relatively large aneurysms unsuitable for treatment by neck clipping or trapping. However, when the bifurcation of the posterior inferior cerebellar artery (PICA) is distal to the occluded point in cases where the PICA bifurcates from the aneurysm or the neck region, blood supply to the aneurysm may persist because anterograde blood flow to the PICA may be preserved. Therefore, clinicians must consider the possibility of aneurysm rupture after proximal occlusion in the following cases: 1) when the aneurysm is large or giant, but non-thrombosed; 2) when thrombosis occurs soon after the procedure; 3) when postoperative angiography shows partial filling of the aneurysm with contrast agent through the contralateral vertebral artery of basilar artery or the cervical muscle branches.

We performed balloon dilatation in the carotid artery of WHHL rabbits and examined subsequent morphological alteration over time. The balloon was inserted as far as the carotid bifurcation and observations were made on the morphological alteration after dilatation in the atherosclerotic intimal thickening from immediately after balloon dilatation over a period of ten months. Immediately after balloon dilatation, endothelial cells came of circularly and stretching, fragmentation off elastic fibers and coming off of smooth muscle cells of the media were confirmed. No change in the degree of thickening after dilatation was seen in the atherosclerotic intimal thickening of the carotid bifurcation. Three weeks later, endothelium covering except some parts, circular neointima and fibrosis of the media were observed; foamy cells had accumulated in the upper layer of the atherosclerotic intimal thickening, and that region was not yet covered with endothelial cells. The progress of fibrous intimal thickening so as to keep the lumen smooth was seen up to six months later, but foamy cells were not found in the neointima.

We report scalp arteriovenous fistulas (AVFs) in which we performed embolization and examine the treatment method. The subjects were four cases of scalp AVF treated by embolization. All cases were male and three had a past history of scalp injury. As the feeding artery, we found a single artery in one case and multiple arteries in three cases. In three cases we employed a transarterial approach by cutting down the scalp and embolized the fistula with NBCA (N-butyl-cyanoacrylate). We conducted the embolization procedure as follows in order to securely occlude the fistula; 1) we obtained the precise location of fistula by the superselective angiography; 2) we induced the tip of microcatheter to immediately in front of fistula; 3) when high flow shunt was manifested, we controlled the flow by retaining the balloon catheter in the external carotid artery; 4) and injected NBCA by compressing around the fistula from above the scalp with a cylindrical instrument to prevent the migration of embolic material to the venous side. As a result, all cases were completely cured and there was no major complication except for transient postoperative pain. If the transfemoral approach to fistula is impossible, it is considered effective to cut down near the fistula and embolize the scalp AVF by direct puncture to the feeding artery with NBCA as embolic material.

P-300, an event-related potential (ERP), is believed to reflect the potential for inherent high-dimension information processing. P-300 is generally detected utilizing an active paradigm in conjunction with an oddball paradigm. However, some reports have shown that the passive auditory paradigm also allows evaluation of patients in a vegetative or comatose state. In this study we have investigated the correlation between P-300 and Glasgow coma scale (GCS). The dominant distribution of P300 topography at peak latency shifted from parieto-occipital to the frontal, temporal regions as consciousness deteriorated.

An irrigation system which can easily be applied to the conventional high-speed air drill was developed to allow simultaneous irrigation during micro-drilling. The irrigation system is constructed with a tube of 0.8 mm outer diameter and supporting rings. Irrigation is entirely coordinated with drilling by a single foot switch. The tube of the system ejects normal saline intermittently toward the cutter bar tip. Use of this system in skull base surgery showed that effective irrigation and a clean operative field was achieved even in a narrow space under the operating microscope, saline is ejected exactly on the point of drilling and over-heating does not occur so that heat-related damage to the local nerves and blood vessels is avoided. The system can easily be applied to any type of high-speed air drill by using supporting rings of the correct size. This irrigation system is particularly useful in microneurosurgery using the high-speed air drill.

Regional cerebral blood flow (rCBF) measurement by laser Doppler flowmetry and cortical temperature measurement using thermoencephaloscopy (TES) were performed to investigate the relationship between the changes in rCBF and cortical temperature after induced cortical spreading depression (CSD) in rats. TES showed a gradually expanding thermoresponse like an extending circular wave after CSD induced by application of KCl. Similarly, a transient increase in rCBF spread from the site of stimulation with a velocity of propagation of 2.5 mm/min. Simultaneous monitoring of rCBF and cortical temperature showed that the transient increase in rCBF was associated with an initial decrease in cortical temperature, followed by an increase in cortical temperature. We suggest that the cortical temperature is regulated mainly by neurogenic control of the pial microvascular blood supply that is precisely adjusted to the metabolic needs of the cerebral cortex. Non-injured cortex with the fine vascular architecture must be preserved during neurosurgery to allow heat transfer from deep areas of the cortex.

We will present a case of arteriovenous malformation with a partial stenosis in the parent artery, left middle cerebral artery (MCA), observed during one year This case was treated by intravascular and conventional surgery. At first percutaneous transluminal angioplasty (PTA) was performed for the stenosis and surgical removal of the nidus followed. The patient was discharged in good condition.

The traditional means of localising the sensory motor cortex during surgery is Penfield's procedure of mapping sensory and motor responses elicited by electrical stimulation of the cortical surface. Another method to define the precise location of precentral and postcentral gyri is the recording of somatosensory evoked potentials to contralateral median nerve stimulation. 1 Wood CC Spencer DD Allison T McCarthy G Williamson PD Goff WR Localization of human sensorimotor cortex during surgery by cortical surface recording of somatosensory evoked potentials. J Neurosurg. 1988; 68: 99-111 Crossref PubMed Scopus (310) Google Scholar However, even with these methods, it is very difficult to define the area on the surface of the cortex because many electrodes must be used. In this study, thermography was used to identify the sensory area during surgery for cerebral glioma situated in the motor and sensory cortex.

In the cortical zone surrounding an ischemic or traumatic focus, CSD is a transient phenomenon involving interstitial ions, blood flow and metabolism and is believed to be completely reversible. However, it may extend to secondary brain injuries because CSD releases excitatory amino acids into the extracellular space. In order to prevent secondary brain injuries, it may be effective to block repeated CSD. This study was designed to determine whether hypothermia can block CSD propagation and whether this study is a potentially useful means for preventing secondary brain injuries. Male wistar rats weighing 270 g on average were used for the experiments. The animals were divided into two groups: hypothermic rats (33.5-34 degrees C, rectal temp.) and normothermic rats (37-37.5 degrees C). The changes in rCBF (regional Cerebral Blood Flow) were monitored in order to observe CSD. LDF (Laser Doppler Flowmetry) was used to measure rCBF. The two LDF probes were placed on the parietal cortex (4 mm apart). To elicit CSD, a needle stab injury was made on the cortex or a piece of paper soaked with 10% KCl was applied on the cortex. The velocity of CSD propagation was more prolonged in the hypothermic rats than in the normothermic rats (p < 0.01). There were smaller numbers of repeated CSD in the hypothermic rats than in the normothermic rats. Histological examination of the cerebral cortex revealed shrinkage neurons more distinctly in the normothermic rats than in hypothermic rats. From these results, we can speculate that hypothermic may block CSD propagation and that hypothermic therapy has the potential to prevent secondary brain injuries.

An accurate knowledge of cerebral anatomy is important in order to evaluate the precise location of a cerebral lesion. Cortical structures are identified by knowledge of the adjacent gyri and sulci; however, white matter tracts are difficult to differentiate from one another due to the lack of clear anatomic landmarks. Therefore, even if MRI shows obvious white matter abnormalities, in some cases it is difficult accurately to localize the lesion. The purpose of this study is to evaluate the location of the main white matter tracts by using three-dimensional MR imaging. MRI study was performed by 1.5 Tesla (Signa: General Electric). Computer assisted analysis with Voxtool software (General Electric) was used to generate both surface brain and tomographic images. The exact anatomic basis of white matter signal abnormalities is important when analyzing patients with disconnective syndromes or neuropsychological deficits such as conduction aphasia, visuospatial deficit etc. This preliminary attempt at constructing a three-dimensional MRI white matter atlas of the brain may be helpful for evaluating the anatomico-clinical correlations in these patients, and also as teaching materials for the clinical (neurologic, neurosurgical), anatomic and radiographic disciplines.

A simple noninvasive method for a quantitative measurement of brain perfusion is presented using intravenous radionuclide angiography with 99mTc-hexamethylpropylene amine oxime (HMPAO). Graphical analysis was employed for the evaluation of the unidirectional influx constant (ku) of the tracer from the blood to the brain and the initial distribution volume (Vn) for the tracer, which is the volume of the exchangeable region plus the plasma space. The ku and Vn values were standardized to provide objective and comparable values, brain perfusion indices (BPI) and corrected Vn (Corr. Vn), between subjects by setting the size ratio of ROI(brain) to ROI(aorta) at 10 and 1, respectively. BPI and Corr. Vn of the whole brain were measured before and 20 min after injection of 1 g acetazolamide. After acetazolamide administration, BPI and Corr. Vn increased in all eight subjects with cerebrovascular diseases and one with a pituitary adenoma, by a mean of x 1.26 and 1.24, respectively. Increase of BPI showed a significant correlation with increase of Corr. Vn. This technique is easy to apply as an adjunct to SPECT and may be helpful in the measurement of brain perfusion changes in the acetazolamide test.

A case with vasospasm of the right anterior cerebral artery induced by hyperventilation is presented. Consecutive Tc-99m HMPAO brain SPECT studies at rest and during hyperventilation greatly contributed to the quantitative evaluation of focal perfusion decrease in conjunction with contrast angiography. This technique seems to be useful for the detection of alterations in regional brain perfusion during short duration intervention.

We studied the effect of acetazolamine (DIAMOXR) on vascular response in areas with crossed cerebellar diaschisis (CCD) using consecutive 99mTc-hexamethyl-propyleneamine oxime (HMPAO) SPECT studies before and after DIAMOX administration with a subtraction method. Regions of interest were drawn over the bilateral cerebellar cortices and interhemispheric asymmetry indices (IAI) were obtained. Eleven of 14 patients with CCD at baseline showed decrease of IAI after DIAMOX administration. Although there is a possibility of underestimation of increase in perfusion in unaffected cerebellar hemisphere, this result suggests a greater increase in perfusion in the affected cerebellar hemisphere as compared with in the contralateral unaffected one and suggests more dilatation of the arterioles in areas with CCD post-DIAMOX than in areas without CCD. However nonsignificant correlation between IAI at baseline and difference of IAI from baseline to post-DIAMOX did not support the hypothesis of more dilatation post-DIAMOX of more constricted arterioles.

We have designed a screening system to diagnose unruptured aneurysms, including the use of digital subtraction angiography (DSA). We surveyed 115 patients who had undergone clipping procedures after subarachnoid hemorrhage (SAH) and questioned them with regard to the subjective symptoms. Sixty-eight of 92 patients who returned the questionnaire reported, prior to rupture, headache, eye pain, and neck pain most frequently, and also impairment of extraocular movements, ptosis, visual field defects, and motor and sensory disturbances. Nineteen (47.5%) of 40 patients who had complete pain relief after surgery complained of headache from 1 week to 1 month before SAH. In addition, nine patients (22.5%) complained of headache for several years, and were also pain-free after surgery. For the indication of DSA, we employed an expert system based on fuzzy set theory. Seven groups of parameters are: Group 1, a basic questionnaire concerning age, sex, and past and family histories; Group 2, 15 warning signs selected on the basis of retrospective study; and Groups 3-7, detailed questions concerning each sign. Scoring weights assigned to each condition based on the results of the retrospective study, and threshold values were determined by several neurosurgeons. The certainty factors for intermediate hypotheses were calculated from these weights and threshold values and summed up, from which the conclusion was obtained. Twelve new cases of unruptured cerebral aneurysm were diagnosed using this screening system. This system may improve the ability to diagnose cerebral aneurysms before rupture.

A low energy Nd-YAG laser by using a contact laser scalpel, with a rod made of artificial sapphire, attached to a Nd-YAG laser was employed in a vascular anastomosis experimentally.The common carotid arteries of forty Wister's rats were used in this study. The optimal laser energy for a satisfactory fusion of the cut edge of the common carotid artery was found to be 1.0 watt in power and 1.0 second in duration at 0.2mm diameter of the tip of the rod. After two stay suture done, the laser was irradiated. The duration of the procedure was 3 to 5 minutes.The patency rate of the anastomosed vessels was as high as 87.5%. Histological specimens stained with H.E. and elastica van Giesan were examined until 2 months after the surgery.In histological findings 2 weeks after the surgery, all layers of the vessels were adequately connected by welding of lots of collagen fibers. Subsequently, a granulation which led to stenotic changes was not observed in the chronic stage. In conclusion the reason for the healing of the anastomotic site was not clearly confirmed, however the collagen fibers were grown up like a biological paste by laser heating.

Low powered Ga. Al, As laser is used for the treatment of occipital neuralgia, neck-shoulder-arm pain and lumbaric pain cases. Effect of laser treatment is as follows;“Occipital neuralgia”, excellent 28.1%, good 53.1%, fair 12.5% poor 6.3%,“neck-shoulder-arm pain”, excellent 42.1%, good 36.8%, fair 14.1%, poor 7.0%,“Lumbaric pain”excellent 20.5%, good 29.1%, fair 37.6%, poor 12.8%. The period of pain relief is varid, but at least for more than 4~7 days pain relief is obtained.