PubMed Health⌕ Search

Biomedical subjects

H Touho

Publications and source records attributed to H Touho.

At least 73 records · Page 4Linked to original sources

Long-term follow-up study after extracranial-intracranial bypass surgery for anterior circulation ischemia in childhood moyamoya disease.

Between May, 1974, and March, 1991, 104 patients with moyamoya disease, all under 16 years old at the time of first surgery, underwent superficial temporal-to-middle cerebral artery anastomosis and/or encephalomyosynangiosis. The mean follow-up period was 9.6 years (range 4.8 to 16.0 years). Hemiplegia was the most frequent symptom before the first operation. Transient ischemic attacks (TIA's) were noted in 57 patients and minor stroke with hemiplegia in 44. The most frequent type of cortical dysfunction was aphasia (21 cases). Postoperatively, the incidence of TIA's and/or completed stroke with motor weakness of the extremities was markedly decreased, but visual disturbance progressed and major or minor stroke with visual disturbance was found in two cases. In patients under the age of 3 years, a major stroke prior to surgery resulted in a poor outcome in 36% of cases. Preoperative major stroke in patients between the ages of 3 and 7 years was less frequent, and poor outcomes were seen in 17% of this group. There were no major preoperative strokes in patients with surgery after the age of 7 years, and no poor outcomes were recorded in this group. A major preoperative stroke prior to surgery had adverse impact on the ultimate patient intelligence quotient (IQ) following surgery. All patients operated on after the age of 7 years had a normal or borderline IQ at follow-up examination.

Adolescent↗

Continuous alprenolol infusion for control of hypertension in the acute stage of ruptured intracranial aneurysms.

The clinical benefits and hemodynamic effects of continuous alprenolol infusion for control of hypertension in the acute stage of ruptured cerebral aneurysms were investigated. Twenty-five patients manifesting systemic hypertension (greater than 160/100 mmHg) were treated with alprenolol, a beta-adrenergic antagonist, phentolamine, an alpha-adrenergic antagonist, and trimethaphan camsilate, a ganglionic blocker, given intravenously. All drugs decreased the mean arterial blood pressure significantly. However, alprenolol decreased the heart rate and cardiac index while phentolamine increased them. Alprenolol also decreased arterial catecholamine and renin activity, but caused no change in central venous pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, and systemic vascular resistance. The results indicate the usefulness of continuous alprenolol infusion for the control of acute hypertension in hemorrhagic cerebrovascular disease. The mode of action of alprenolol is also discussed.

Adult↗

Neurosurgical application of a flow-directed oximetry thermodilution catheter for evaluation of cerebral blood flow--technical note.

The neurosurgical application was evaluated of a flow-directed oximetry thermodilution catheter for measurement of oxygen saturation in the jugular vein, which reflects cerebral blood flow (CBF). The catheter allows estimation of changes in CBF during carotid endarterectomy and therapeutically induced hypertension in the management of delayed vasospasm after subarachnoid hemorrhage.

Catheterization, Swan-Ganz↗

Direct calorimetry using Swan-Ganz catheter for evaluation of general metabolic expenditure in acute cerebrovascular disease--comparison between direct Fick method and indirect calorimetry technique.

Oxygen consumption calculated by the direct Fick method using a Swan-Ganz catheter (D-VO2) and indirect calorimetry using a metabolic computer (ID-VO2), carbon dioxide production calculated by the latter method, and respiratory quotient were determined pre- and postoperatively in 12 patients with acute hypertensive intracerebral hemorrhage and eight patients with acute ruptured intracranial aneurysm. The mean D-VO2 value was slightly lower than the mean ID-VO2 value, but had a significantly positive correlation. The regression curve was very close to the line of identity. The total metabolic expenditure can be calculated from D-VO2 and daily urinary nitrogen excretion. Direct calorimetry using a Swan-Ganz catheter is a simple method to evaluate metabolic expenditure in acute hemorrhagic cardiovascular disease.

Acute Disease↗

Cerebral blood flow measurements using stable xenon CT with very short inhalation times.

A noninvasive, simplified method using inhalation of stable xenon (Xe(s)) and computed tomographic (CT) scanning to estimate regional cerebral blood flow (rCBF) and regional partition coefficient (r lambda) is described. Twenty-four patients with cerebrovascular occlusive disease and six volunteer controls inhaled 30% Xe(s) and 70% oxygen for 180 seconds and exhaled for 144 seconds during serial CT scanning without denitrogenation. The end-tidal Xe(s) concentration was continuously monitored with a thermoconductivity analyzer to determine the build-up range (A value) and build-up rate constant (K value) for arteries with the curve fitting method. The time-CT number (Hounsfield unit) curve for cerebral tissue during the Xe(s) washin and washout phases was used to calculate r lambda and rCBF using least squares curve fitting analysis. The resultant r lambda and rCBF map demonstrated a reliable distribution between the gray and white matter, and infarcted areas. rCBF was high in gray matter, low in white matter, and much lower in infarcted areas than in white matter, r lambda was high in white matter, low in gray matter, and much lower in infarcted areas. Xe(s) CT-CBF studies with very short inhalation of 180 seconds is a clinically useful method for evaluation of rCBF in patients with cerebrovascular diseases.

Administration, Inhalation↗

Successful excision of a juvenile-type spinal arteriovenous malformation following intraoperative embolization. Case report.

The case of a 57-year-old woman with a 14-year history of progressive paraparesis is presented. Selective spinal angiography revealed a juvenile-type spinal arteriovenous malformation (AVM) with a typical large size and rapid flow. The AVM was located primarily in the retromedullary space at the cervicothoracic junction. The AVM was successfully obliterated by intraoperative embolization using isobutyl-2-cyanoacrylate and surgical excision.

Arteriovenous Malformations↗

Vertebrobasilar insufficiency: stable xenon computed tomography-cerebral blood flow study in posterior circulation revascularization.

Preoperative and postoperative local cerebral blood flow were measured by the stable xenon computed tomography-cerebral blood flow technique in 15 patients with vertebrobasilar insufficiency. The surgery included end-arterectomy or angioplasty of the vertebral artery (five cases), superficial temporal artery-superior cerebellar artery anastomosis (eight cases), and superficial temporal artery-posterior cerebral artery anastomosis (two cases). Fourteen (93.3%) of the 15 patients improved in the post-operative period. Low local cerebral blood flow in the ischemic area without infarction manifested a constant and significant increase postoperatively. In summary, the stable xenon computed tomography-cerebral blood flow technique is thought to be a simple and useful method for assessing local cerebral blood flow in posterior circulation perioperatively.

Aged↗

Hemodynamic evaluation in patients with superficial temporal artery-middle cerebral artery anastomosis--stable xenon CT-CBF study and acetazolamide.

Sixteen patients with minor completed stroke in the chronic stage underwent superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. The acetazolamide-activated regional cerebral blood flow (rCBF) was measured 20 minutes after the injection using inhalation of stable xenon and computed tomographic scanning (Xes CT-CBF study) pre- and postoperatively. Eleven patients (Group 1) showed immediate improvement in neurological state within a few days of the operation, while five (Group 2) showed no improvements. Preoperative rCBF in the ischemic areas without infarction was 30.8 +/- 3.0 ml/100 gm/min in Group 1 and 53.0 +/- 5.2 ml/100 gm/min in Group 2. Preoperative vasodilatory capacity with acetazolamide in Group 1 was 5.7 +/- 8.6 and significantly increased to 19.8 +/- 4.9 after surgery. In Group 2, pre- and postoperative vasodilatory capacity was 12.7 +/- 3.1 and 14.9 +/- 2.9, respectively, and there was no significant change. These results suggested that minor stroke patients with moderate decrease of affected side rCBF (less than 40 ml/100 gm/min) and with hemodynamic impairment may have the surgical indication for STA-MCA anastomosis.

Acetazolamide↗

Measurement of energy expenditure in acute stage of cerebrovascular diseases.

Oxygen consumption (VO2), carbon dioxide production, respiratory quotient, urinary nitrogen excretion (UN), resting energy expenditure (REE), REE rate (%REE) and consumption rates of carbohydrate (%C), fat (%F) and protein (%P) were pre- and postoperatively measured in the acute stage of 17 patients with cerebrovascular diseases. They included six of ruptured intracranial aneurysms, six of cerebrovascular occlusion, and five of hypertensive intracerebral hemorrhage. Preoperative VO2, UN, REE, and %REE were 185.1 ml/min, 7.1 gm/day, 1280 cal/day, and 132.6, respectively. %C, %F, and %P were 40.9, 38.5, and 20.6, respectively. Especially the preoperative %P had markedly increased. Postoperatively, %C significantly decreased to 28.3, and %P showed a significant increase up to 30.3. Patients with ruptured intracranial aneurysms manifested a significant increase of %P and %F and a decrease of %C, postoperatively. In summary, the catabolism of fat and protein increases in the acute stage, especially postoperatively, and this hypermetabolic state should be considered when caring for patients with cerebrovascular diseases as malnutrition might prevent wound healing and cause weight loss and a decrease in immunity.

Acute Disease↗

Clinical application of stable xenon CT-CBF studies without denitrogenation.

Noninvasive and simplified methods for estimating regional cerebral blood flow (CBF) and regional partition coefficient (lambda) using the inhalation of stable xenon (Xes) and computed tomographic (CT) scanning are described. Thirty percent Xes in 70% oxygen was inhaled for 240 seconds and exhaled for 160 seconds during serial CT scanning without denitrogenation in 26 patients with cerebrovascular diseases and four volunteer controls. During the investigation, the end-tidal Xes concentration was continuously monitored with a thermoconductivity analyzer to determine the build-up range (A value) and build-up rate constant (K value) of the artery by the curve fitting method. Calculated A and K values were corrected by the following formulae reported previously: for patients aged 0-20 years, Ae = 0.75Aa + 2.15, Ke = 0.67Ka + 0.69; 21-40 years, Ae = 0.56Aa + 3.24, Ke = 0.38Ka + 1.12; 41-60 years, Ae = 0.91Aa + 1.95, Ke = 0.38Ka + 1.32; over 61 years, Ae = 0.52Aa + 3.81, Ke = 0.31Ka + 1.55 (Ae and Ke were calculated with end-tidal Xes concentration, Aa and Ka were calculated by direct sampling of arterial blood). A CBF map (f map) and lambda map made with corrected A and K values demonstrated reliable distribution. The CBF was high in the gray matter, low in the white matter, and much lower in the infarcted area. lambda was high in the white matter, low in the gray matter, and much lower in the infarcted area. Eight patients were examined with and without denitrogenation. Both the f map and lambda map with denitrogenation were compatible with those without denitrogenation.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Inhalation↗

Addition computed tomography with stable xenon--special reference to ischemic cerebrovascular diseases.

Stable xenon (Xes) is used as a contrast agent because it freely diffuses to cerebral tissues through the blood-brain barrier. In this study, 2 axial levels for Xes enhancement analysis were selected from a baseline series of computed tomographic (CT) scans and 6 serial CT scans were obtained every 20 seconds for each scan level during the 240 seconds inhalation period of 30% Xes in 10 volunteer controls and in 52 patients with ischemic cerebrovascular diseases (ICVD). The serial CT scans were added and averaged in each pixel. This was used to make a new CT picture (addition CT scan). The CT scans before the Xes inhalation, the scan at the end of the Xes inhalation, and the addition CT scan were compared to see whether gray matter and ischemic areas could be differentiated from white matter. The addition CT scans could differentiate the three structures very well in both the acute and chronic stages of ICVD. This technique is thought to be a very simple and useful method to detect the small infarcted areas and low perfusion areas that cannot be visualized on precontrast CT scans.

Administration, Inhalation↗

Hemodynamic evaluation before and after the STA-MCA anastomosis--with special reference to measurement of regional transit time with intra-arterial digital subtraction angiography.

Twenty-seven patients with minor completed and major stroke in the chronic stage underwent superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. The regional cerebral blood flow (rCBF), using inhalation of stable xenon and computed tomographic scanning (Xes CT-CBF study), and the mode of transit time (MTT) in the MCA territory using intra-arterial digital aortography were measured. Activated rCBF and MTT was measured 20 minutes after the administration of acetazolamide (10 mg/kg) in 14 patients. Nineteen of the 23 patients with minor stroke (Group 1) showed immediate improvement in their neurological state within a few days of the operation, while four patients with minor stroke (Group 2) and four patients with major stroke (Group 3) showed no improvement. Based on the rCBF obtained with the Xes CT-CBF study, affected side rCBF/unaffected side rCBF and %f [(peak DSA number/affected side MTT)/(peak DSA number/unaffected side MTT)] were compared. There was a significant positive correlation. Affected side MTT in Group 1 was 6.41 +/- 1.16 sec, preoperatively, and significantly decreased to 5.13 +/- 0.91 sec after the operation. On the other hand, preoperative MTT in Group 2 was 4.40 +/- 0.81 sec and 4.76 +/- 0.89 sec, postoperatively. Preoperative %f in Group 1 was 0.514 +/- 0.143 and significantly increased to 0.739 +/- 0.154, postoperatively. Group 2 showed no change. Vasodilatory capacity with acetazolamide showed a marked improvement in Group 1, postoperatively. Our study indicated that if MTT is moderately lengthened, %f is moderately decreased, and vasodilatory capacity is impaired, in patients with minor ischemic stroke will benefit from STA-MCA anastomosis.

Angiography, Digital Subtraction↗

Mechanism of the re-buildup phenomenon in moyamoya disease--analysis of local cerebral hemodynamics with intra-arterial digital subtraction angiography.

The authors investigated the mechanism of the re-buildup phenomenon on electroencephalogram in 14 patients of moyamoya disease with superficial temporal artery-middle cerebral artery anastomosis. Visualization of the lateral view of the common carotid angiography was performed with intra-arterial digital subtraction angiography (IA-DSA), using a 4/sec x 3 sec + 2/sec x 5 sec + 1/sec x 5 sec film sequence. The catheter tip was inserted into C5/6 level and 250 mgI/ml of iopamidol was used as the contrast agent; 6 ml in total was injected over 1.5 seconds. Circulation times of the common carotid artery (C3 portion)-ascending parietal vein (delta TTPs) and common carotid artery-internal cerebral vein (delta TTPD) were measured before hyperventilation (HV), immediately after HV, and 3 minutes after HV during pre- and postoperative periods. delta TTPD in the preoperative period was prolonged by HV and was normalized at 3 minutes after HV but delta TTPs were prolonged immediately after and 3 minutes after HV. In the postoperative period, however, these values did not change significantly immediately after and 3 minutes after HV. These findings indicate that delayed cerebral blood flow response to HV is a pathogenetic factor of the re-buildup phenomenon in moyamoya disease.

Adolescent↗

Hypermetabolism in the acute stage of hemorrhagic cerebrovascular disease.

Oxygen consumption (VO2), carbon dioxide production (VCO2), urinary nitrogen excretion, respiratory quotient, resting energy expenditure (REE), %REE, and the consumption rates of carbohydrate, fat, and protein (%CHO, %Fat, %Prot, respectively) were determined pre- and postoperatively by indirect calorimetry in 13 patients with ruptured intracranial aneurysms and 11 patients with hypertensive intracerebral hemorrhage in the acute stage. The preoperative VCO2, VO2, urinary nitrogen excretion, respiratory quotient, REE, and %REE were, respectively (mean +/- standard deviation): 171 +/- 46 ml/min, 203 +/- 56 ml/min, 10.3 +/- 1.7 gm/day, 0.84 +/- 0.01, 1397 +/- 389 Cal/day, and 129% +/- 8%. The values for VCO2, VO2, REE, and %REE were all increased above normal levels. The %Prot was increased to 26.1% +/- 9.1%. In the postoperative period, the VCO2, VO2, urinary nitrogen excretion, REE, and %REE significantly increased to: 186 +/- 44 ml/min, 229 +/- 56 ml/min, 14.8 +/- 2.9 gm/day, 1557 +/- 384 Cal/day, and 141% +/- 21%, respectively. The %Fat and %Prot also increased significantly, but the %CHO significantly decreased. Preoperatively, in the patients with ruptured intracranial aneurysms, there was a greater increase in %Prot in eight patients classified (according to Fischer) as having a Group 3 or 4 subarachnoid hemorrhage (SAH) on computerized tomography than in five patients classified as having a Group 1 or 2 SAH. In summary, increased metabolic expenditure, especially increased catabolism of protein and fat, is characteristic of accompanying hemorrhagic cerebrovascular disease, and there is an increase in consumption of fat and protein in the postoperative period. Lack of precise knowledge about the cause and consequences of these metabolic responses makes it impossible at present to judge the optimal extent of nutritional replacement. The hypermetabolic state should be taken into consideration when caring for these patients as it may cause weight loss, poor wound healing, and susceptibility to infection.

Acute Disease↗

[Transbrachial artery approach for selective cerebral angiography].

Transaxillary or transbrachial approaches to the cerebral vessels have been reported, but selective angiography of all four vessels has not been possible through one route. In this report, a new technique for selective cerebral angiography with transbrachial approach is described. One hundred and twenty three patients with cerebral infarction, vertebrobasilar insufficiency, intracerebral hemorrhage, epilepsy, or cerebral tumor were examined. Those patients consisted of 85 outpatients and 38 inpatients whose age ranged from 15 years old to 82 years old. The patients were examined via the transbrachial approach (97 cases via the right brachial, 29 cases via the left). Materials included a DSA system (Digital Fluorikon 5000, General Electric Co.), a 4 French tight J-curved Simmons 80-cm catheter, a 19-gauge extra-thin-wall Seldinger needle, and a J/Straight floppy 125-cm guidewire. Generally, the volume of the contrast agent (300 mgI/ml iopamidol) used in the common carotid artery angiogram was 6 ml, while that used in the vertebral artery angiogram was 4ml. If catheterization of the vertebral artery or right common carotid artery was unsuccessful, about 8ml of the contrast agent was injected into the subclavian or brachiocephalic artery. Definitive diagnosis and a decision on proper treatment of the patients can be easily obtained, and the results were clinically satisfactory. Moreover, no complications were encountered in this study. This new technique making a transbrachial approach to the cerebral vessels using the DSA system is introduced here. Neurosurgeons can use this technique easily, and they will find that it provides them with all the information they need about the patient.

Adolescent↗

Neurogenic pulmonary edema in the acute stage of hemorrhagic cerebrovascular disease.

Extravascular lung water (EVLW) was measured by the double-indicator dilution method in 25 patients with hemorrhagic cerebrovascular diseases. EVLW had a significantly positive correlation with both alveolar-arterial oxygen difference (AaDO2) and intrapulmonary shunt. The value of EVLW in the acute stage in 15 patients with increased AaDO2 more than 20 mm Hg was 7.8 +/- 2.2 ml/kg and that in the chronic stage 4 weeks after onset significantly decreased to 4.6 +/- 0.7 ml/kg (P less than 0.001). The value of EVLW in the acute stage in 10 patients with normal AaDO2 less than 20 mm Hg was 4.7 +/- 1.1 ml/kg and that in the chronic stage 4 weeks after onset was 4.5 +/- 0.2 ml/kg. There was no significant difference between them. Pulmonary arterial blood pressure, pulmonary capillary wedge pressure, central venous pressure, cardiac index, systemic vascular resistance index, and pulmonary vascular resistance index in the acute stage in the 25 patients were all within the normal range. Three patients with neurogenic pulmonary edema had markedly increased EVLW without abnormalities in pulmonary arterial blood pressure, pulmonary capillary wedge pressure, central venous pressure, cardiac index, systemic vascular resistance index, and pulmonary vascular resistance index. From these facts, the main cause of the increase in EVLW cannot be explained by left ventricular failure, but can be explained by high permeability pulmonary edema.

Adult↗

[Hypoxemia in the acute stage of hypertensive intracerebral hemorrhage, with special reference to increased extravascular lung water].

Respiratory responses to acute brain damage have been well documented. Severe hypoxemia of unknown origin has often been seen in the acute stage of intracerebral and subarachnoid hemorrhage. Neurogenic pulmonary edema is a particular concern in the neurosurgical intensive care setting. In this study, the extravascular lung water volume (EVLW), alveolar-arterial oxygen difference (AaDO2), and intrapulmonary shunt (QS/QT) were measured in 17 patients with hypertensive intracerebral hemorrhage in the acute stage. The mean AaDO2, QS/QT, and EVLW values were 19.1 mmHg, 7.7%, and 5.49 ml/kg, respectively. The mean pulmonary arterial, central venous, and pulmonary capillary wedge pressures were all within the normal ranges. Eight patients with an AaDO2 of 20 mmHg or more manifested abnormal increases in QS/QT and EVLW, the mean values of which were 10.3% and 6.52 ml/kg, respectively. Nine patients with an AaDO2 of less than 20 mmHg exhibited normal QS/QT and EVLW, with mean values of 5.4% and 4.57 ml/kg, respectively. There was a significant, direct correlation between AaDO2 and EVLW. AaDO2 and EVLW in 11 measured cases either stayed normal or normalized within 4 weeks. These results suggest that acute congestive heart failure and/or pulmonary hypertension were not the main causes of the increase in AaDO2 and EVLW; the increase in EVLW might be explained by increased permeability of pulmonary vessels. The results of this study suggest that an increase in EVLW is causally related to hypoxemia. Further studies of lung water are necessary if we are to better understand respiratory abnormalities associated with acute-stage hypertensive intracerebral hemorrhage.

Cerebral Hemorrhage↗