Large ependymal cyst of the cerebello-pontine angle in a child

Most ependymal cysts occur intracerebrally, with a few cases situated in the subarachnoid space. The cerebellopontine angle is a common site for arachnoid cysts, but a very rare site for ependymal cysts. A case is described here of a large ependymal cyst in the cerebellopontine angle. A 12-year-old girl with left hearing disturbance was admitted. CT and MRI revealed a cystic tumor in the left cerebellopontine angle. At operation, we obtained a discrete thin-walled cyst which had arisen from a continuation of the choroid plexus of the lateral foramen of Luschka, which had no connection with the arachnoid. The cyst proved to be an ependymal cyst.

Emergency X ray-guided nasotracheal intubation in a patient with a spinal epidural haematoma

A patient with a spinal epidural haematoma who developed tetraparesis and respiratory insufficiency is described. Nasotracheal intubation was successfully and rapidly undertaken with the aid of continuous fluoroscopy.

[Preoperative sedation for childhood moyamoya disease--clinical evaluation of rectally administered midazolam]

We evaluated the effectiveness of rectally administered midazolam for preoperative sedation in 26 cases of childhood moyamoya disease. The patients, aged 5.0 +/- 1.8 yr (mean +/- SD), received 1 mg.kg-1 of midazolam 30 min prior to induction of anesthesia. The patient's level of sedation, tolerance of anesthesia face mask, and amnesia were evaluated. In 22 of 26 patients induction via face mask was performed smoothly, and excellent anterograde amnesia was observed. Remarkable complications, including hemodynamic and/or respiratory depression, were not noted. The level of sedation was significantly related to the patient's age. Although further investigation to evaluate proper dose are needed, 1 mg.kg-1 of rectally administered midazolam is useful for childhood moyamoya disease, in which crying can worsen the neurological symptoms.

The "turn-over" technique for selective cerebral angiography

In older patients with severe aortic atherosclerosis or pronounced tortuosity of the brachiocephalic vessels, selective catheterisation may be impossible. In order to overcome this difficulty we introduced a new "turn-over" technique. This involves introduction of a long guidewire through the catheter, advancing it and turning it over just above the aortic valves and finally introducing it into each major vessel, followed by the catheter. Selective catheterisation was completely achieved with the turn-over technique in 13 patients. Turning over the catheter just above the aortic valves and introducing it into the vessels was very easy.

Effect of thiopentone on motor evoked potentials induced by transcranial magnetic stimulation in humans

We have studied the effect of repeated doses of thiopentone on motor evoked potentials (MEP) after transcranial magnetic stimulation in 13 patients. Thiopentone was administered i.v. in an initial dose of 2 mg kg-1, followed by repeated doses (1 mg kg-1 every 3 min) until the appearance of burst suppression on the EEG. The total dose administered was mean 10.7 (SD 2.6) mg kg-1. The magnetic coil was placed over the MEP scalp stimulation region and evoked electromyographic responses were recorded from the contralateral abductor pollicis brevis. After an initial dose of thiopentone, reproducible MEP responses were recorded in all patients, but amplitudes were reduced to 42.8% of baseline values. Further administration of repeated doses of thiopentone produced a dose-dependent decrease in success rate of MEP recordings and a significant reduction in MEP amplitude (P < 0.01). Latency did not change significantly, although there was a tendency to increase. During burst suppression on the EEG, MEP was not recorded successfully in all patients. We conclude that MEP recording during the administration of thiopentone is feasible only at a minimum dose, with a marked reduction in MEP amplitude.

[Spike discharge detected by intra-arterial electroencephalography from intra-arterial guide wire in temporal lobe epilepsy]

The implantation of electrodes for intracranial electroencephalography (EEG) recording as presurgical evaluation of patients with intractable epilepsy is at present most important for planning epilepsy surgery. This method is most effective in temporal lobe epilepsy. We carried out intracranial EEG by means of insulated micro guide wire for endovascular surgery in two temporal lobe epilepsy cases, and spike discharges could be detected in lesional medial temporal lobe. Case 1 is a 29 year-old-male suffered from intractable complex partial seizure (CPS) for 18 years. He was diagnosed as left temporal lobe epilepsy and performed removal of amygdala, hippocampus, parahippocampal gyrus and fusiform gyrus. Case 2 is a 16 year-old-lady suffered from drug resistant CPS for 4 years. Under the diagnosis of right temporal lobe epilepsy, temporal lobectomy was performed. As the presurgical evaluation, under the implantation of subdural strip electrode in both cases, we carried intra-arterial EEG after angiography. Seeker Lite-10 guide wire was insulated with Tracker-10 unibody infusion catheter at sphenoidal portion of middle cerebral artery, and frequent interictal spike discharge was detected in lesional medial temporal lobes by two methods simultaneously.

Transbrachial approach with turn over technique for selective cerebral angiography--technical note

A new technique to obtain selective internal carotid, external carotid and vertebral artery angiograms through the transbrachial route using a special 4-Fr long catheter and long guidewire positioned by a turn over technique is described. The technique was used in 25 geriatric patients to obtain angiograms without persistent complications.

Long-term follow-up study of "epileptic type" moyamoya disease in children

Twenty-three patients with epileptic type moyamoya disease are reviewed among 200 moyamoya disease patients. Ten boys and 13 girls aged 5 months to 12 years were followed over 6 months to 17.3 years. Six had generalized seizure and 17 had focal seizure. Operations were performed within 1 year in eight patients, within 1-3 years in five, and more than 3 years after onset in 10. Nineteen patients improved and suffered no seizure without receiving antiepileptic drugs, but four patients developed true epilepsy and three of these suffered cerebral infarction. Multivariate analyses showed that toddlers aged less than 1 year and mild or severe abnormal computed tomographic (CT) findings correlated with a bad outcome. This study showed that epileptic type moyamoya disease has the same clinical features as transient ischemic attack or infarction type. Age under 1 year and CT abnormalities indicate a poor prognosis and necessity for early reconstructive surgery.

Cerebral revascularization using omental transplantation for childhood moyamoya disease

Between January, 1986, and October, 1990, 30 children with moyamoya disease, aged from 2 to 17 years, underwent omental transplantation to either the anterior or the posterior cerebral artery territory. The mean follow-up period was 3.8 years, ranging from 1.6 to 6.4 years. Seventeen patients had symptoms of monoparesis, paraparesis, and/or urinary incontinence and were treated using unilateral or bilateral omental transplantation to the anterior cerebral artery territory. Eleven patients had visual symptoms and were treated with unilateral or bilateral omental transplantation to the posterior cerebral artery territory. Two patients had symptoms associated with both the anterior and the posterior cerebral arteries, and were treated with dual omental transplantations. All 19 patients treated with omental transplantation to the anterior cerebral artery and 11 (84.6%) of the 13 treated with omental transplantation to the posterior cerebral artery showed improvement in their neurological state. Patients with more collateral vessels via the omentum had more rapid and complete improvement in their neurological state. Patients with severe preoperative neurological deficits associated with the posterior cerebral artery had persistence of their symptoms.

Anastomosis of occipital artery to anterior inferior cerebellar artery with interposition of superficial temporal artery. Case report

A 56-year-old man with vertebrobasilar insufficiency and associated findings including quadriparesis, dysarthria, cerebellar ataxia, nystagmus, and somnolence underwent left occipital artery (OA) to anterior inferior cerebellar artery (AICA) anastomosis with interposition of a superficial temporal artery (STA) graft. This procedure was chosen because cerebral angiograms demonstrated occlusion of the right vertebral artery (V3) and severe stenosis of the V4 segment of the left vertebral artery, with perfusion of the territory of the left posterior inferior cerebellar artery via the ipsilateral AICA, and because dissection of the OA is a relatively difficult and time-consuming procedure. Dissection of the STA, on the other hand, is much easier. Preoperative measurements of local cerebral blood flow in the vertebrobasilar circulation before and after intravenous administration of acetazolamide (500 mg) were obtained, and demonstrated low flow and hemodynamic compromise in the posterior circulation. The patient's hemodynamic and neurological status improved following surgery. In this report, we present a new and simplified method of OA-AICA anastomosis with interposition of STA graft.

Surgical reconstruction of failed indirect anastomosis in childhood Moyamoya disease

Thirty-one patients with moyamoya disease, who had been treated for encephaloduroarteriosynangiosis (EDAS), encephalomyosynangiosis (EMS) or EMS with encephaloarteriosynangiosis (EAS) in other hospitals, were admitted to Osaka Neurological Institute from January 1985 to September 1991. Twenty-seven of 57 sides treated by indirect anastomosis showed good filling of the middle cerebral artery (MCA) territory via the anastomosis, whereas 16 and 14 showed fair and poor collaterals via the anastomosis, respectively. Twenty-eight cerebral hemispheres treated by indirect anastomosis underwent further surgery and received superficial temporal artery-MCA anastomosis with or without EMS for still-existent recurrent transient ischemic attacks or completed stroke even after the indirect anastomosis. One patient still had recurrent transient ischemic attacks with quadriparesis after bilateral encephaloduroarteriosynangiosis, which had produced no effective collaterals in the MCA territory; the patient then underwent omental transplantation to the bilateral anterior cerebral artery and MCA territories, resulting in the cessation of the transient ischemic attacks. Clinical improvement after superficial temporal artery-MCA anastomosis with or without EMS was noted in all patients, except on one side, where a completed stroke had resulted in fixed neurological deficits. We do not know the reasons for the uncertainty of the development of collaterals via the indirect anastomosis, but there are many patients who still need direct reconstruction of the indirect anastomosis.

[Clinical application of calculation software of the four rules of arithmetic on computed tomography]

Calculation program software of the four rules of arithmetic in computed tomography (CT) has been introduced for clinical purposes since 1990. Evaluation of hemodynamic reserve and cerebral autoregulation can be calculated using this software in ischemic cerebrovascular diseases and delayed cerebral vasospasm after ruptured intracranial aneurysms. Eight hemodynamic maps can be entered and calculation based on the four rules of arithmetic can be performed between them and shown visually. For example, delta CBF [CBF after administration of acetazolamide (B)-CBF before its administration(A)] and % CBF [(B - A)/A x 100] maps are useful in evaluation of the capacity of hemodynamic reserve in ischemic cerebrovascular diseases. And delta CBF [CBF before induced hypertension using intravenous dopamine administration (B)-CBF during induced hypertension (A)] and % CBF [(B - A)/A x 100] also can be used in evaluation of cerebral autoregulation and decision concerning indication of the need for induced hypertension during the period of delayed cerebral vasospasm after subarachnoid hemorrhage.

[Surgical excision of a huge olfactory groove meningioma by extensive transfrontal approach]

A case with a huge olfactory groove meningioma was cured surgically by extensive transfrontal approach. A 46-year-old female was admitted with complains of left visual disturbance. CT revealed a large high-density mass in the base of the frontal fossa which was enhanced homogenously. Hyperostosis was seen in the planum sphenoidale. MRI showed a relatively low intensity with a peritumoral low-intensity rim on T1WI and high intensity on T2WI. The brain stem had shifted dorsally. Rich feeding to the lesion from the ethmoidal artery was seen on angiography. An operation was performed using an extensive transfrontal approach. After bifrontal craniotomy, orbitofrontal osteotomy was performed. This approach enabled us to minimize frontal lobe retraction, to interrupt the blood supply to the tumor early, and to remove the tumor completely from the frontal base and to present invasion of the sinuses. The postoperative course was uneventful without cosmetic problems.

[Multiple subpial transection after lesionectomy in an intractable epilepsy case]

A Sixty-one-year-old man was admitted to our hospital because of generalized convulsion. He had suffered from intractable epilepsy for 26 years. CT and MRI showed the right frontal cavernous angioma. On operation, intraoperative electrocorticography was performed after lesionectomy including surrounding glial scar and hemosiderin laden tissue. It showed epileptiform potentials in neighbor gyrus of the lesion. Because the removed sphere would be so broad, and we performed multiple subpial transection (MST). After MST, depression of background electrical activity and disappearance of spike discharge are seen. One and half year after operation, seizure was controlled by only phenobarbital administration.

[Surgical excision of a cavernous angioma of the cerebral peduncle by orbito-fronto-malar approach]

A case with cavernous angioma at the left cerebral peduncle was cured surgically. A 36-year-old male was admitted with complaints of right facial palsy, right motor disturbance and cheiro-oral syndrome. CT revealed a round high-density mass in the left cerebral peduncle and thalamus. Angiography showed no abnormality. MRI showed a round high-intensity mass on T1-and T2-weighted image in the left thalamus, which meant hematoma at a subacute stage and mixed-intensity core in the left cerebral peduncle, which was cavernous angioma. Symptoms disappeared, and high-density also disappeared gradually, but rebleeding occurred. Because of this, an operation was performed by the orbitofrontmalar approach. Hematoma and angioma were removed under ABR and SEP monitor, which showed no abnormality during the operation. Histological examination of the surgical specimen revealed that the abnormal vessels were cavernous angioma. The postoperative course was uneventful without cosmetic problems.

Comparison of dynamic CT and stable xenon CT in ischemic cerebrovascular disease

PURPOSE

To investigate a new hemodynamic parameter that can be obtained by dynamic CT and that reflects cerebral blood flow (CBF), in patients with ischemic cerebrovascular disease.

METHODS

CBF and hemodynamic parameters including the area under the time-dependent contrast-medium dilution curve (A) and mean transit time (MTT) were measured in 23 patients with ischemic cerebrovascular disease. They included 17 patients in the chronic stage (more than 1 month after onset) and six with acute occlusion of the internal carotid or middle cerebral artery (within 24 hours of onset). CBF measurement was conducted by inhalation of stable xenon during CT scan and the hemodynamic study was performed using dynamic CT.

RESULTS

CBF in the territory of the middle cerebral artery had an inverse correlation with MTT. (A) divided by (MTT) defined as (f) had a significantly positive correlation with CBF (MTT = 18.66 - 0.495.CBF + 0.005.CBF2, r = .730, P < .001).

CONCLUSION

This parameter (f) is thought to represent a relative CBF and it can be used in evaluation of the hemodynamic status in ischemic cerebrovascular disease.

Superselective embolization of spinal arteriovenous malformations using the Tracker catheter

Eighteen patients with spinal arteriovenous malformations had been treated with conventional embolization, surgical removal, feeder ligation, and/or feeder coagulation between February 1985 and March 1990. The lesions included six glomus, four juvenile, three extramedullary, and five dural arteriovenous malformations or fistulas. Embolic therapy was conducted in 14 patients by introducing the tip of a catheter into the segmental arteries and injecting polyvinyl alcohol strips (500-1000 microns) (conventional embolization). Follow-up spinal angiography disclosed recanalization in 10 patients (71.4%) and the appearance of new feeding arteries in five patients (35.7%). We introduced the Tracker vascular access system in April 1990. Eight patients (four glomus, one juvenile, and three dural arteriovenous malformations) were treated with the minicatheter and Ivalon particles (150-350 microns). Five patients showed neurological improvement immediately after treatment. The other three patients had severe paraparesis before treatment and did not show any improvement. One patient with a glomus-type arteriovenous malformation showed transient neurological deterioration just after embolization with the Tracker-10 to occlude a lesion fed by the posterior spinal artery, because the Ivalon particles migrated into the anterior spinal artery via the anterior spinal canal artery. In one patient with a juvenile arteriovenous malformation, the Tracker-18 catheter perforated the radiculomedullary artery originating from the right vertebral artery, and subarachnoid hemorrhage occurred. However, the Tracker-10 could later successfully occlude the arteriovenous malformation. The rates of recanalization and appearance of the new feeding vessels were 4/8 (50.0%) and 2/8 (25%), respectively.

Evaluation of therapeutically induced hypertension in patients with delayed cerebral vasospasm by xenon-enhanced computed tomography

Serial cerebral blood flow (CBF) measurements were made with stable xenon-enhanced computed tomography in 20 patients with angiographically confirmed ruptured intracranial aneurysms, before and during induced hypertension with continuous infusion of dopamine. All patients showed angiographic vasospasm during their course. Twelve patients without symptomatic vasospasm (Group 1) had the lowest hemispheric CBF on the craniotomy side of 31.6 +/- 6.8 ml/100 gm/min on days 4-9 (control value, 40.1 +/- 2.0 ml/100 gm/min), while the other eight patients with symptomatic vasospasm (Group 2) had the lowest hemispheric CBF on the craniotomy side of 25.0 +/- 7.6 ml/100 gm/min on days 10-14. The critical hemispheric CBF inducing neurological deficits was about 20 ml/100 gm/min in Group 2. Dysautoregulation was usually present in Groups 1 and 2, but therapeutically induced hypertension could reverse the delayed neurological deficits, if begun early at the stage of delayed vasospasm.

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.

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.

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.

[Anesthetic management of revascularization for moyamoya disease]

Anesthetic management during 85 STA-MCA anastomoses with or without encephalo-myosynangiosis for 64 patients with Moyamoya disease was evaluated retrospectively. Anesthetic agents included nitrous oxide-NLA (GONLA), nitrous oxide-halothane (GOF), nitrous oxide-enflurane (GOE), and their combinations. Slight hypercarbia (40 mmHg less than PaCO2 less than 50 mmHg) was essential to avoid cerebral ischemia. Several procedures to control heart rate by beta blockade or to control hypertension by nitroglycerin were required, because tachycardia and hypertension interfered with fine surgical procedure. During microsurgery HR of GONLA anesthetized patients was significantly lower. Postoperatively the patients anesthetized by GOE showed significantly lower PaCO2 compared with the GONLA anesthetized patients. So we recommend GONLA for anastomosis in patients with Moyamoya disease.

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.