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Biomedical subjects

K Houkin

Publications and source records attributed to K Houkin.

At least 55 records · Page 3Linked to original sources
PubMed1998

Vascular reconstruction using interposed small vessels.

OBJECTIVE: This study presents the relationship between the patency of short-vessel graft bypasses and their diameter/length. METHODS: The authors performed interposed graft bypass operations using small vessels for four patients with moyamoya disease, six patients with cerebral thrombosis, and one patient with aortitis syndrome. The donor artery was the superficial temporal artery (10 patients) or the occipital artery (1 patient), and the recipient artery was the cortical branch of the middle cerebral artery (8 patients) or the cortical branch of the anterior cerebral artery (3 patients). The interposed graft used between these donor and recipient vessels was the superficial temporal vein (seven patients), the superficial temporal artery (three patients), or the epigastric artery (one patient). RESULTS: Good patency of the graft was confirmed for 7 of these 11 patients. Regarding the relationship between the diameter/length and the patency, we found that long-term patency could not be expected when the discriminant function of y = (15.39 x diameter) - (0.35 x length) - 14.37 was below zero. CONCLUSION: Short-vessel graft bypass is a practical option for cerebral revascularization surgery when short large vessels are used.

Adult↗
PubMed1998

Multiple dural arteriovenous fistulas.

Four patients with multiple intracranial dural arteriovenous fistulas (DAVFs) at separate sites were treated by endovascular techniques (transarterial and/or transvenous embolization), surgery (excision or isolation), radiotherapy, or combinations, according to the pathophysiological condition. All lesions in two patients were obliterated completely without neurological deficit. There were residual fistulas after the treatment in two patients, but these were low-grade lesions without retrograde cortical venous drainage, and marked clinical improvement was obtained. Planning of treatment strategies for multiple DAVFs requires careful analysis of the venous drainage from the affected sinuses and cerebral hemodynamics.

Aged↗
PubMed1997

Metabolic and neurological patterns in chronic cerebral infarction: a single-voxel 1H-MR spectroscopy study.

The details of brain metabolism in chronic cerebral infarcts have not been clarified. Using proton MR spectroscopy (1H-MRS) at 1.5 T, we measured biochemical changes in 16 patients with large infarcts involving the motor cortex in the chronic phase (median 293.9 days) and related the findings to clinical data. Localised spectra were obtained using point-resolved spectroscopy, with an echo time of 270 ms. Regions of interest were placed on the frontal lobe, including the precentral gyrus and central sulcus. Motor function was assessed by the manual muscle power test at the time of the 1H-MRS study. Only three patients with severe paresis had no signal in the lesions and a lactate signal was obtained in 13 cases. N-acetyl aspartate (NAA) was observed in 4 cases with recanalisation of an occluded vessel. Motor function correlated strongly with the NAA/choline-containing compounds (Cho) ratio (P < 0.01) and lactate/Cho ratio (P < 0.01). We found various metabolic patterns, reflecting residual neurological function.

Adult↗
PubMed1997

Combined revascularization surgery for childhood moyamoya disease: STA-MCA and encephalo-duro-arterio-myo-synangiosis.

We present surgical techniques for optimal revascularization in childhood moyamoya disease. During the past 10 years we performed revascularization surgery for childhood moyamoya disease using direct revascularization with superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis and indirect revascularization of encephalo-duro-arterio-myo-synangiosis (EDAMS) 43 times. Points of this surgery are as follows: (1) craniotomy and dural opening for the most extensive possible exposure of the brain surface, (2) protective manipulation of the STA, temporal muscle and middle meningeal artery, (3) STA-MCA anastomosis to the frontal branch of the MCA to improve cerebral circulation of the frontal lobe using a small branch of the STA, and (4) a small opening in the arachnoid membrane and watertight closure.

Brain Ischemia↗
PubMed1997

Induction of cytokines, chemokines and adhesion molecule mRNA in a rat forebrain reperfusion model.

Cellular damage secondary to reperfusion following ischemic insult has been hypothetically attributed to an inflammatory cascade concerted by cell-to-cell interactions. While the role of several cytokines and adhesion molecules in reperfusion injury of the brain has been explored to a certain extent, their regulatory and temporary profiles remain unclear. We have addressed the temporal features of the induction of mRNA for proinflammatory cytokines, adhesion molecules and chemokines at an acute phase subsequent to reperfusion in rat forebrain. Semiquantitatively calibrated reverse transcription-polymerase chain reaction analysis was employed to assess the relative expression of mRNA for intercellular adhesion molecule (ICAM)-1, interleukin (IL)-1 alpha, IL-1 beta, 1L-2, 1L-6, tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, monocyte-chemoattractant protein (MCP)-1, and macrophage migration inhibitory factor (MIF). The increase in mRNA from the basal levels after reperfusion followed one of two different patterns; an increase occurring as early as 1 h, or a slight increase continuing up to 24 h after reperfusion. The former pattern was seen for ICAM-1, IL-1 alpha, IL-1 beta, TNF-alpha, and MCP-1, and the latter for IL-6 and MIF. These results were consistent with the proinflammatory properties of the immediately induced cytokines, which may be involved in the initiation step of the inflammatory cascade, causing the secondary cellular responses and finally leading to further brain damage.

Animals↗
PubMed1997

Vasoreconstructive surgery for radiation-induced vasculopathy in childhood.

BACKGROUND: Cerebral vasculopathy associated with the appearance of netlike vessels can develop following irradiation therapy for parasellar brain tumors, especially in children. However, little is known regarding the clinical course of this disease or the appropriate therapy for it. CASE REPORTS: We experienced two surgically-treated patients with radiation-induced vasculopathy and reviewed the previously reported cases. Both of our patients were treated with encephalo-duro-arterio-myo-synangiosis combined with superficial temporal artery to middle cerebral artery (STA-MCA) bypass. Their ischemic symptoms improved following the surgery, associated with a good angiographic neovascularization from the STA-MCA bypass, as well as dural and muscular arteries. CONCLUSION: Our findings and the review of the previous reports suggested that surgical therapy may be beneficial for the patients with radiation-induced vasculopathy with the appearance of netlike vessels.

Brain Ischemia↗
PubMed1997

Low cerebral blood flow and perfusion reserve induce hyperperfusion after surgical revascularization: case reports and analysis of cerebral hemodynamics.

BACKGROUND: Hyperperfusion syndrome after surgical revascularization is a rare complication and there has not been any systematic study on factors that induce hyperperfusion after surgery. In this paper, we retrospectively analyzed the factors related to this syndrome. PATIENTS AND METHODS: We performed 46 cases of surgical revascularization including 33 cases of carotid endarterectomy (CEA) and 13 cases of superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis during the past 5 years. Among these, we encountered three cases of hyperperfusion syndrome despite well-controlled blood pressure postoperatively. To evaluate factors related to the occurrence of hyperperfusion syndrome, we examined four parameters: (1) regional cerebral blood flow (rCBF), (2) the increase in the ratio of the postoperative rCBF compared to the preoperative rCBF (increase ratio), (3) cerebral perfusion reserve presented by the increase of rCBF after acetazolamide administration (delta rCBF), and (4) the difference in mean blood pressure between the preoperative and postoperative state (delta BP). RESULTS: Preoperative rCBF was significantly lower in cases of hyperperfusion syndrome than the control cases (p < 0.01 Mann-Whitney U-test). Moreover delta rCBF was evidently lower in the hyperperfusion cases than the control (p < 0.05 Fisher's exact method). However, there was no significant difference in the delta BP between the hyperperfusion cases and the control cases. CONCLUSION: In cases of marked low perfusion (low rCBF) with poor perfusion reserve (low delta rCBF), hyperperfusion after surgical revascularization can occur even if blood pressure is adequately controlled.

Aged↗
PubMed1997

Evaluation of cytokines in cerebrospinal fluid from patients with moyamoya disease.

We investigated the levels of angiogenic growth factors in cerebrospinal fluid (CSF) from patients with Moyamoya disease and from those with atherosclerotic occlusive disease to evaluate the relationship of these factors to the pathogenesis of Moyamoya disease. CSF from Moyamoya patients contained significantly higher concentrations of basic fibroblast growth factor (b-FGF) (P < 0.05). The b-FGF level was apparently elevated in patients with well developed neovascularization after indirect revascularization surgery (P < 0.01). The other angiogenic factors were not significantly elevated compared with those of the control group.

Adult↗
PubMed1997

Familial occurrence of moyamoya disease.

There is extensive evidence that Moyamoya disease has a tendency for multifactorial inheritance, although the pathogenesis of Moyamoya disease is not clear. The authors report five cases showing familial occurrence of Moyamoya disease and analyse its clinical characteristics. In the past 15 years, we have encountered 68 cases of Moyamoya disease. Among these, 14 cases (10 females and four males, five family pedigrees, asymptomatic 1 case) of familial occurrence were observed. In this series, mother-to-child inheritance was observed in five cases, although there were no cases showing father-to-child inheritance. Ten patients were children with an initial onset of cerebral ischemia, at a mean age of 9.7 years. One mother was asymptomatic and two mothers had a past history of cerebral ischemia. Only one patient was a 37-year-old woman with clinical onset of intracerebral hemorrhage. There were no specific clinical characteristics in familial Moyamoya disease compared with those in sporadic Moyamoya disease.

Adult↗
PubMed1997

Direct and indirect revascularization for moyamoya disease surgical techniques and peri-operative complications.

We have performed surgical treatment for Moyamoya disease using the superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis and encephalo-duro-arterio-myo-synangiosis (EDAMS). In this paper, the surgical technique of combined revascularization for Moyamoya disease as well as peri-operative complications are discussed. Craniotomy and dural opening were extensively carried out to expose the brain surface as widely as possible. Dissection of the STA, which is the most powerful resource of direct revascularization, should be carefully carried out using a surgical microscope. The temporal muscle and middle meningeal artery, which have the most potential as sources of indirect revascularization, must be preserved. STA-MCA anastomosis to the frontal branch of the middle cerebral artery is indispensable for improving cerebral circulation of the frontal lobe. A small arachnoid membrane opening and water-tight closure are also important to avoid post-operative subdural and subcutaneous fluid collection. Ischemic events disappeared immediately after surgery in most cases. However, in several cases, transient ischemic attacks recurred for several months after the surgery. Chronic subdural hematoma was seen in two cases.

Adolescent↗
PubMed1997

Induction of macrophage migration inhibitory factor messenger ribonucleic acid in rat forebrain by reperfusion.

OBJECTIVE: Macrophage migration inhibitory factor (MIF) is a cytokine that has the potential to immobilize and activate monocytes/macrophages. To examine whether MIF may potentially be involved in the pathogenesis of reperfusion injury of the brain, we investigated the expression of MIF in a rat model of reperfusion. METHODS: A four-vessel occlusion procedure was performed for 30 minutes using male Wistar rats to obtain a moderate reperfusion in the forebrains. Semiquantitatively calibrated reverse-transcription polymerase chain reaction analysis was conducted to examine temporal profiles of messenger ribonucleic acid (mRNA) expression for MIF and macrophage chemoattractant protein 1. MIF protein assays expression was assessed with specific Western blot analysis. For anatomic mapping of MIF, an immunohistochemical study was performed. RESULTS: Reverse-transcription polymerase chain reaction demonstrated that the mRNA level of MIF increased depending on the duration of reperfusion (< or = 24 h) subsequent to global ischemia. The macrophage chemoattractant protein 1 mRNA was also observed to increase after reperfusional stress, but its maximum expression was reached earlier (1 h after the stress) than was MIF mRNA. Increase of MIF protein was also shown by Western blot. MIF-positive staining was observed in the neuronal processes (neuropil) in the cortex and basal growth ganglia of a rat forebrain. CONCLUSION: This protein is up-regulated and may modulate immunological reaction in secondary brain damage after ischemia and reperfusion stress.

Animals↗
PubMed1997

Pathological consideration of a "blister-like" aneurysm at the superior wall of the internal carotid artery: case report.

OBJECTIVE AND IMPORTANCE: Although the incidence is low, a very small aneurysm with a thin wall and no neck arises at the superior wall of the supraclinoid portion of the internal carotid artery and is called a "blister-like" aneurysm. However, the pathogenesis of such a vascular lesion remains uncertain. CLINICAL PRESENTATION: A 57-year-old man developed a fatal subarachnoid hemorrhage caused by the rupture of a blister-like aneurysm at the superior wall of the internal carotid artery. An autopsy was performed, and the lesion was pathologically examined. RESULTS: The internal elastic lamina and media had disappeared at the border between the eccentrically sclerotic and normal carotid wall. The gap in the internal elastica was covered with normal adventitia and fibrinous tissue. This portion was not composed of collagenous tissue as ordinarily seen in an aneurysmal wall. Neither infiltration of inflammatory cells nor dissection of the artery were observed. CONCLUSION: The blister-like aneurysm appeared to be a laceration of the carotid wall based on degeneration of the internal elastic lamina.

Aneurysm, Ruptured↗
PubMed1997

Effects of surgical revascularization on outcome of patients with pediatric moyamoya disease.

BACKGROUND AND PURPOSE: We reviewed surgically treated patients with pediatric moyamoya disease and examined whether vasoreconstructive surgeries reduced the risk of recurrent ischemic attacks and changed overall outcomes in terms of the patients' performance and intellectual status. METHODS: Sixty-four hemispheric sides in 34 pediatric moyamoya disease patients who received surgical treatment were examined. We performed superficial temporal artery to middle cerebral artery (STA-MCA) bypass and encephalo-duro-arterio-myo-synangiosis (EDAMS) on 48 sides (combined group) and indirect bypass surgery such as EDAMS on 16 sides (indirect group). These 34 patients were observed postoperatively from 1 to 14 years (mean +/- SD, 6.6 +/- 3.8 years) and were examined for the incidence of recurrent ischemic attack. Of the 34 patients, 23 were followed up for > 5 postoperative years, and their overall outcomes in terms of their performance and intellectual status were determined. RESULTS: Perioperative ischemic events (< or = 2 weeks after surgery) occurred in 5 surgeries (31%) of the indirect group and in 6 (13%) of the combined group (P = NS). The incidence of postoperative ischemic events (> 2 weeks after surgery) was significantly reduced in the combined group (10%) compared with the indirect group (56%; P < .01). Of the 23 patients observed > 5 years, 7 patients (30%) were mentally retarded and regarded as having a fair outcome. CONCLUSIONS: Combined surgery (STA-MCA bypass with EDAMS) for pediatric moyamoya disease was effective in reducing the risk of postoperative ischemic attacks compared with indirect surgery. Surgical revascularization may be effective in preventing intellectual deterioration and improving overall outcome.

Adolescent↗
PubMed1997

Differentiation of cerebral radiation necrosis from tumor recurrence by proton magnetic resonance spectroscopy.

Proton magnetic resonance spectroscopy (1H MRS) was evaluated for distinguishing between radiation necrosis and recurrent glioma in 11 patients after high-dose radiotherapy. Six patients had a histological diagnosis of recurrent glioma. Four patients had a histological diagnosis of radiation necrosis and one had a clinical course consistent with the diagnosis of radiation necrosis. 1H MRS showed cases of radiation necrosis had two characteristic 1H MRS patterns: markedly increased lactate/creatine and phosphocreatine (Cr) ratio and decreased choline-containing compounds/Cr ratio compared to that of recurrent glioma; or all the major metabolites were completely diminished. The N-acetyl aspartate signal was not helpful for differential diagnosis. 1H MRS is a potentially useful method for differentiating tumor recurrence from radiation necrosis in patients treated for malignant glioma.

Adult↗
PubMed1997

Childhood ischemic stroke caused by fibromuscular dysplasia of the intracranial artery--case report.

An 8-year-old girl presented with fibromuscular dysplasia of the intracranial vessels manifesting as ischemic stroke. Neuroimaging showed infarction of the right putamen and ipsilateral frontal white matter. Angiography revealed "string of beads" sign involving the terminal portion of the right internal carotid artery and the horizontal segment of the ipsilateral middle cerebral artery. She was treated conservatively. Magnetic resonance angiography at 2 months post ictus showed similar findings in the middle cerebral artery but improvement of the stenosis of the internal carotid artery. Her neurological deficits had almost resolved. Fibromuscular dysplasia should be part of the differential diagnosis of ischemia in children.

Brain Ischemia↗
PubMed1997

Aneurysm of the anterior communicating artery associated with accessory middle cerebral artery--case report.

A 63-year-old female presented with an anterior cerebral artery aneurysm associated with accessory middle cerebral artery. The aneurysm was located on one of the duplicate anterior communicating arteries, and the accessory middle cerebral artery originated from the anterior cerebral artery adjacent to this aneurysm. The recurrent artery of Heubner was not recognized. The accessory middle cerebral artery may have been involved in the genesis of the aneurysm by changing the hemodynamics in the anterior cerebral arteries.

Cerebral Angiography↗
PubMed1997

Effectiveness of fibrin glue for preventing postoperative extradural fluid leakage.

Cerebrospinal fluid (CSF) leakage through dural sutures after craniotomy increases the risk of complications such as persistent CSF fistulas, meningitis, and subcutaneous, graft bone, or epidural infections. The effectiveness of fibrin glue for preventing CSF leakage through dural closure was investigated in 183 patients who underwent frontotemporal craniotomy for unruptured aneurysm. Fibrin glue was used in 138 patients, but not in the other 45. Computed tomography was used to evaluate postoperative extradural fluid collection as a minimal volume of low-density area. Postoperative computed tomography demonstrated transient increases in extradural fluid collection in 55 patients. However, none of these patients received a second surgery for dural repair. Fluid collection occurred in 19 of 45 patients (42%) in whom fibrin glue was not used, and in 36 of 138 patients (26%) in whom fibrin glue was used. The fibrin sealant on the dural suture was a significant factor in reducing the incidence of the fluid leakage (p < 0.05, chi-square test). Fibrin glue is a useful surgical tool for the prevention of postoperative extradural fluid collection through the dural sutures.

Cerebrospinal Fluid↗