Carotid endarterectomy with external shunt: a new device and indication for use: technical note.

OBJECTIVE: We designed a new external shunt system and evaluated its indications and efficacy in patients undergoing carotid endarterectomy (CEA). METHODS: In 8 of 332 CEA procedures, external shunts were placed between the common carotid artery and the internal carotid artery (ICA). This procedure was implemented for one of two indications: 1) a change in electroencephalographic and/or somatosensory evoked potential readings immediately after ICA occlusion, or 2) elongation of the ICA made safe insertion of an internal shunt impossible. In addition, a shunt was placed between the common carotid artery and the external carotid artery to establish collateral circulation from the external carotid artery to the intracranial circulation, which is essential during ICA occlusion. RESULTS: All external shunts were functional, and electroencephalography and somatosensory evoked potentials demonstrated no significant abnormalities during the CEAs. All patients awoke from surgery without manifestation of new neurological deficits. CONCLUSION: Our new external shunt device proved safe and efficacious in cases that did not permit the placement of an internal shunt.

Application of the distraction technique to scaphocephaly.

The case of a 1-year-old boy who underwent correction of a scaphocephalic deformity using distraction devices is described. Double pi-shaped osteotomies were cut. Bilateral temporal bone flaps were gradually expanded, and the frontal bone was pulled back simultaneously. The patient showed a good skull contour 2 years postoperatively. Although previous distractions were aimed only at expansion of the cranium, we used the distraction technique to successfully shorten the cranial vault in the anteroposterior direction. This case demonstrates that the osteotomized bone flaps can be moved in various directions. This feature of the distraction technique may contribute greatly toward meticulous reconstruction of the cranial vault.

Coronary artery stenosis evaluated by combined carotid and coronary angiography in patients undergoing carotid endarterectomy.

The relationship between coronary artery stenosis and the postoperative outcome was investigated in patients who underwent carotid endarterectomy (CEA). The benefit of combined carotid and coronary angiography was also evaluated. Combined carotid and coronary angiography was performed in 72 patients treated with CEA (mean age 64.0 years). Fourteen patients with a history of ischemic heart disease (IHD) had a higher Gensini score for coronary artery stenosis than patients with no history of IHD (37.9 +/- 36.8 vs. 7.9 +/- 12.5, p < 0.0001). However, 39.7% of patients with no history of IHD had a Gensini score exceeding 6. Patients with diabetes mellitus had a significantly higher Gensini score than nondiabetic patients. Eleven patients (15.3%) underwent percutaneous transluminal coronary angioplasty and three (4.2%) underwent coronary artery bypass grafting during the CEA perioperative period. None of the patients who underwent combined angiography showed signs of IHD during or after CEA (mean follow-up period 30 months). Combined angiography was not performed in 189 previous patients. Of these, two died of acute myocardial infarction in the postoperative period, 11 manifested nonfatal IHD, and 18 succumbed to IHD (mean follow-up period 8 years). Although patients with a history of IHD manifested more severe coronary artery stenosis than patients without such a history, the possibility of coronary artery stenosis must be considered in patients with no history of IHD, especially those with diabetes mellitus. Combined carotid and coronary angiography and careful management of coronary artery stenosis can be expected to decrease the mortality and morbidity in patients treated with CEA.

Hyperperfusion syndrome following carotid endarterectomy: evaluation using diffusion-weighted magnetic resonance imaging--case report.

A 65-year-old female developed hyperperfusion syndrome following carotid endarterectomy for severe stenosis of the left internal carotid artery. Transcranial Doppler monitoring showed a sharp increase in flow velocity in the middle cerebral artery (MCA). Diffusion-weighted magnetic resonance (MR) imaging demonstrated diffuse hyperintensity in the region of the left MCA, which diminished markedly 9 days later. The abnormal hyperintensity decreased as the patient's symptoms improved, suggesting that diffusion-weighted MR imaging can be used for evaluating the course of hyperperfusion syndrome.

Hyperperfusion syndrome after extracranial-intracranial bypass in a patient with moyamoya disease--case report.

A 47-year-old female developed hyperperfusion syndrome after superficial temporal artery-middle cerebral artery (STA-MCA) bypass for moyamoya disease. She presented with right hemiparesis and motor aphasia due to left cerebral infarction. She underwent left STA-MCA bypass. One day after surgery, she manifested neurological deterioration. Magnetic resonance (MR) imaging 4 days after the operation indicated regional edema in the territory supplied by the bypass, and single photon emission computed tomography 17 days after the operation demonstrated hyperperfusion in that area. Symptoms improved within 1 week after surgery, and MR imaging showed disappearance of edema and return to the preoperative appearance. Such events are rare, but hyperperfusion syndrome may occur after STA-MCA bypass for moyamoya disease.

Transient ischemia induces an early decrease of synaptic transmission in CA1 neurons of rat hippocampus: electrophysiologic study in brain slices.

We examined the functionality of hippocampal CA1 neurons at early times after transient global ischemia, by electrophysiologic recordings in brain slices. Transient ischemia was conducted on rats using the method of 15-minute four-vessel occlusion, and brain slices were obtained from these animals at different times after ischemia. Within 24 hours after insult, CA1 neurons showed no substantial damage as identified by morphologic means, but exhibited dramatic decreases in synaptic activities by 12 hours after insult, which became further decreased at more extended times after recovery. Blocking gamma-aminobutyric acid A (GABAA) receptors with bicuculline produced a reversible augmentation of the diminished synaptic responses in slices prepared from 12-hour postinsult animals, but failed to do so in slices obtained from rats 24 hours after insult. Recorded in whole-cell mode, the minimum depolarizing current required to elicit an action potential was about twofold larger in the ischemic CA1 neurons than in sham controls, suggesting that an elevated spiking threshold exists in these neurons. We suggest that decreases in electrophysiologic activities precede the morphologic deterioration in postischemic CA1 neurons. The early decrease in CA1 synaptic activities may be associated with an imbalance between glutamate-mediated synaptic excitation and GABAA-mediated synaptic inhibition, whereas substantial impairments in synaptic transmission likely take place after prolonged post-ischemic recovery.

Transient ischemia differentially increases tyrosine phosphorylation of NMDA receptor subunits 2A and 2B.

Activation of the N-methyl-D-aspartate (NMDA) receptor has been implicated in the events leading to ischemia-induced neuronal cell death. Recent studies have indicated that the properties of the NMDA receptor channel may be regulated by tyrosine phosphorylation. We have therefore examined the effects of transient cerebral ischemia on the tyrosine phosphorylation of NMDA receptor subunits NR2A and NR2B in different regions of the rat brain. Transient (15 min) global ischemia was produced by the four-vessel occlusion procedure. The tyrosine phosphorylation of NR2A and NR2B subunits was examined by immunoprecipitation with anti-tyrosine phosphate antibodies followed by immunoblotting with antibodies specific for NR2A or NR2B, and by immunoprecipitation with subunit-specific antibodies followed by immunoblotting with anti-phosphotyrosine antibodies. Transient ischemia followed by reperfusion induced large (23-29-fold relative to sham-operated controls), rapid (within 15 min of reperfusion), and sustained (for at least 24 h) increases in the tyrosine phosphorylation of NR2A and smaller increases in that of NR2B in the hippocampus. Ischemia-induced tyrosine phosphorylation of NR2 subunits in the hippocampus was higher than that of cortical and striatal NR2 subunits. The enhanced tyrosine phosphorylation of NR2A or NR2B may contribute to alterations in NMDA receptor function or in signaling pathways in the postischemic brain and may be related to pathogenic events leading to neuronal death.

[Management and long-term follow-up results in patients with carotid artery dissection].

The recognized incidence of extra- and intracranial carotid artery dissection has increased concomitantly with the progress and development of diagnostic methods. However, management for this condition is still controversial. We report in the present study the management and long-term follow-up results of 15 patients with carotid artery dissection. Mean age of the patients at onset was 47.8 years old, and male/female ratio was 12:3. Two patients were considered to be traumatic dissections and the other 13 patients were spontaneous dissections. Dissection occurred in 10 patients at the extracranial carotid artery, in 4 at the intracranial carotid artery and in 1 at the middle cerebral artery. Nine of 15 patients demonstrated hemiparesis and 5 complained of headache or facial pain. However, it was not possible to identify a characteristic symptom of dissection. Final diagnosis of dissection was made by cerebral angiography in all patients. Serial angiography was carried out in 10 of those, and 5 of the 10 patients showed some improvements of dissection in the cerebral angiogram. Treatment for those patients was selected according to the neurological and angiographical changes. Five patients were managed conservatively and 10 patients underwent surgical revascularization. During the follow-up period (mean 77.6 months), none of them showed any symptoms of reattack, and all but one, who died of heart failure 193 months after revascularization surgery, have lived independently. Although diagnosis of dissection was difficult because of the lack of characteristic symptom, serial angiography was a useful method for diagnosis and adequate management has led to a good clinical outcome.

Carotid endarterectomy for radiation-induced carotid artery stenosis.

A 60-year-old male presented with radiation-induced left carotid artery stenosis. Carotid endarterectomy was performed successfully without postoperative deficits. Carotid endarterectomy is the therapeutic management of choice for these lesions.

Perifocal brain oedema in experimental brain abscess in rats.

An experimental cerebral abscess model in which staphylococcus aureus was inoculated into the brain parenchyma of rats was evaluated for perifocal brain oedema. Blood-brain barrier permeability was studied using various kinds of tracers; sodium fluorescein as a small molecule and Evans blue and HRP as macromolecular tracers. Brain abscess with clear delineation of fibrous capsule formation were found in all animals. Extravasation of tracers was demonstrated in the capsule (Evans blue), extracellular space (HRP) and white matter (sodium fluorescein). There were two types of oedema formation, so called vasogenic oedema and cytotoxic brain oedema.

Neonatal brain abscess with intracystic hemorrhage--case report.

The authors describe the case of an 11-day-old boy with high fever and signs of meningeal irritation in whom computed tomography demonstrated a large brain abscess with intracystic hemorrhage in the right temporal lobe. Cerebrospinal fluid analysis indicated purulent meningitis caused by Escherichia coli. After aspiration of the abscess contents, the entire ventricular system gradually enlarged. Despite repeated ventricular drainage and ventriculoperitoneal shunting, the lateral horn of the left lateral ventricle remained dilated. The isolation of the lateral ventricle may have resulted from septation due to the inflammatory reaction. This fluid was also shunted to the peritoneal cavity.

Multiple cavernous hemangiomas of the orbits.

Intraocular tumors were detected in both orbits simultaneously by computed tomography scanning in a 45-year-old woman complaining of proptosis of the right eye, decreased visual acuity, and diplopia. The tumor in the right orbit was resected by the subfrontal extradural approach, and that in the left orbit by the Krönlein-Berke method. The right tumor was found on the side of the external ear of the muscle cone and the left tumor was located inferiorly on the side of the external ear of the muscle cone. Both tumors were cavernous hemangiomas with identical macroscopic and histologic features.

[Cavernous hemangioma of the frontal bone].

A 44-year-old woman was admitted to our department because of a painless lump on her forehead. Physical examinations were normal except for this lump. Both laboratory data and neurological findings were normal. Plain skull radiograph showed a 4.5 X 5.0 cm honeycombed radiolucent defect in the frontal bone. CT scan demonstrated this lucent defect as a reticular pattern by means of changing the window levels. Moreover, invasive lesion of the inner table which could not be identified in the plain radiographs, was also demonstrated on CT. A left common carotid angiogram showed irregular pooling of contrast material in the radiolucent area of the frontal bone. Angiographically, blood supplies to this tumor were mainly contributed by the frontal branches of the middle meningeal artery and a meningeal branch of the anterior falx artery from the terminal portion of the ophthalmic artery. A bone scintigram revealed accumulation of radioisotope in the lesion. A highly vascular tumor, which was partially adherent to the underlying dura, was removed as en bloc. Postoperative course was uneventful. The histology revealed thin-walled dilated vessels between the trabeculae, and it was diagnosed as cavernous hemangioma of the bone. Hemangioma of the calvarium is estimated to constitute 0.2% of all osseous neoplasms and 10% of primary benign neoplasms the of the skull. Hemangioma of the skull frequently involves the frontal bone. The condition is often found in middle-aged females. The symptom is only a slowly growing, painless lump in most of the cases.(ABSTRACT TRUNCATED AT 250 WORDS)