In situ freezing of the brain for metabolic studies: evaluation of the "box" method for large experimental animals.

The box method of freezing the brain in situ was assessed in baboons. The cooling rate of the tissue was monitored in several regions located at various depths from the skull surface. These measurements allowed us to examine the time required for the tissue to reach 0 degree C, in relation to its depth measured from the top of the skull. To define brain regions with proven ischaemia, frozen tissue sections were surveyed for areas of decreased pH. In addition, concentrations of ATP, phosphocreatine, and lactate were determined in gray matter located at various depths from the top of the brain surface. Normal tissue pH and low lactate concentration, without any significant decrease in high-energy phosphate levels, were found in regions at a depth less than approximately 10 mm from the brain surface. Deep structures including the inferiomedial aspect of the temporal lobe, the lateral geniculate body, and the limbic system (hippocampus) consistently showed mild tissue acidosis, indicating that these regions were subjected to some degree of ischaemia before they were reached by the freezing front. In some cases, acidosis was also detectable in the thalamus, basal ganglia, and in the deeper part of some sulci. We conclude that, with baboons, in situ freezing using the box method is valid for metabolic studies of the cerebral cortex and structures located at a depth less than approximately 10 mm from the top of the brain surface.

Brain tissue concentrations of ATP, phosphocreatine, lactate, and tissue pH in relation to reduced cerebral blood flow following experimental acute middle cerebral artery occlusion.

Local CBF (LCBF) was compared with the corresponding local tissue concentration of ATP, phosphocreatine (PCr), and lactate in anaesthetized baboons subjected to focal ischaemia produced by middle cerebral artery occlusion (MCAO). LCBF hydrogen electrodes were implanted in cortical regions where MCAO had been previously shown to produce severe and penumbral ischaemia and in posterior regions where blood flow is not altered. Metabolites were assayed in small tissue samples collected either by cryoprobe biopsy in the regions where LCBFs were measured (series 1) or by sampling appropriate regions of the rapidly frozen brain (series 2). Subsequent topographical study of brain tissue pH with umbelliferone was performed in this latter series. The results from these two series are compared and discussed in terms of the more appropriate way to perform simultaneous electrode measurements and analysis of tissue samples for studying focal ischaemia in the primate brain. They confirm that the concentrations of ATP and PCr decrease, and that lactate level increases, with decreasing blood flow. These metabolites tended to change more rapidly below a blood flow threshold, rather than showing a steady decrease as the blood flow was reduced, although the variability of the data precluded us from establishing this with confidence. Topographical study of tissue pH often showed sharp boundaries between zones of very low pH and regions with normal pH.

Acute intracranial hypertension and brain-stem blood flow. An experimental study.

This study has been carried out to evaluate the effect of supratentorial mass lesions on the local cerebral blood flow (CBF) of the brain stem. Local CBF of the thalamus, inferior colliculus, and medulla oblongata, and supra- and infratentorial pressure were serially measured in 52 cats with intracranial hypertension produced by supratentorial balloon expansion. The mean control local CBF's in the thalamus, inferior colliculus, and medulla oblongata were 37.5, 42.1, and 30.7 ml/100 gm/min, respectively. At 20 to 30 mm Hg of supratentorial pressure, the local CBF of the thalamus started to decrease, and at 20 mm Hg of infratentorial pressure, the local CBF of the inferior colliculus began to decrease. Finally, at 40 to 60 mm Hg of infratentorial pressure, the local CBF of the medulla oblongata was affected. At the beginning of uncal herniation, indicated by anisocoria, the mean local CBF of the inferior colliculus abruptly decreased from 33.7 to 19.6 ml/100 gm/min in 16 cats. The Cushing response was evoked at a mean supratentorial pressure of 93.4 mm Hg and infratentorial pressure of 49.9 mm Hg in 16 cats. When the systemic arterial pressure was increased to the highest level in 13 cats, the mean local CBF of the medulla oblongata did not show significant change (a decrease from 22.8 to 20.9 ml/100 gm/min). The results suggest that at the beginning of uncal herniation, the local CBF of the upper brain stem markedly decreased. During the Cushing response, the local CBF of the medulla oblongata did not change significantly.

The clinical significance of the P15 wave of the somatosensory evoked potential in tentorial herniation.

Somatosensory evoked potentials (SEPs) to median nerve stimulation and auditory brainstem evoked potentials (BAEPs) were recorded in 16 comatose patients who had suffered transtentorial herniation (TH) due to intracranial haematoma, hydrocephalus or tumour. An attempt was made to correlate the changes in the N14-P15 component of the central conduction time (CCT) and the I-V interpeak latencies (IPLs) of the BAEP with the clinical severity of TH. The N14-P15 component was not affected in seven patients at the diencephalic or early third-nerve stage, and six of these seven showed normal I-V IPLs. All six patients at the late third-nerve/midbrain stage or worse, however, showed abnormalities in the N14-P15 components. Interestingly, five patients showed dissociation of SEP and BAEP abnormalities suggesting a differential sensitivity of the medial and lateral lemnisci in the brainstem to ischaemia and/or compression. All five patients in whom the P15 potential was absent on either side had a poor outcome and there was a correlation between the electrical failure in the N14-P15 component and the degree of brainstem damage caused by TH as assessed clinically. Reversible loss of the P15 potential by brainstem retraction has been shown in intraoperative SEP monitoring during aneurysm surgery. Prolonged compression of the upper brainstem seems to cause irreversible loss of the P15 which should be regarded as being due to irrecoverable brainstem dysfunction.

Effects of temporary arterial occlusion on somatosensory evoked responses in aneurysm surgery.

Changes in the central conduction time (CCT) during the application of temporary clips were studied in 40 patients who had undergone operations for intracranial aneurysms in relation to postoperative neurological outcome. Ten of these 40 patients (25%) showed postoperative morbidity, although promptly recoverable in 5. None of the patients whose CCTs did not change following temporary occlusion of major vessels showed any postoperative morbidity, except in one case of anterior cerebral artery aneurysm. In 6 patients, temporary vascular occlusion caused a considerable transient prolongation in CCT of up to 10 msec. Two of these 6 patients were associated with postoperative neurological deficit (which was recoverable in 1). The cortical response became flat in 15 patients. Seven of these 15 patients showed hemispheric deficits postoperatively, although recoverable in 4. There was a correlation between the change in the somatosensory evoked response and postoperative outcome. Disappearance of the N20 potential following occlusion is regarded as a danger signal, but postoperative, irrecoverable neurological deficit seems to be unlikely if its disappearance takes more than 3-4 minutes. Even if the cortical response disappears, the clinical outcome is expected to be good if the N20 potential recovers within 20 minutes after recirculation.

Intracranial aneurysm due to metastatic choriocarcinoma.

The case of a woman with an episode of subarachnoid hemorrhage 2 days after delivery is presented. An emergency operation was performed, and an intracerebral clot from a ruptured aneurysm was removed. Histologic examination of the resected aneurysm showed metastasis from a choriocarcinoma to the aneurysmal wall. Six cases of intracranial aneurysm due to metastasis of choriocarcinoma are reviewed.

Ossifying fibroma of the thoracolumbar spine: a case report and review of the literature.

A 43-year-old woman with ossifying fibroma of the thoracolumbar vertebrae was presented with a 6-month history of progressive radiculomyelopathy. The symptoms were successfully treated by laminectomy and partial resection of the lesion. This is the first reported case of ossifying fibroma involving the thoracolumbar spine. The clinical significance and management of this rare lesion are discussed with a review of the literature.

Brain abscess associated with congenital pulmonary arteriovenous fistula.

A case of brain abscess associated with congenital pulmonary arteriovenous fistula was presented and 52 reported cases were reviewed. The brain abscess was successfully treated with repeated aspiration and drainage, and the pulmonary arteriovenous fistula, located in the right lower lobe, was resected. The arteriovenous fistula occurs as a common pulmonary manifestation of hereditary hemorrhagic telangiectasia; however, no symptoms suggesting these two were noted in this case. Brain abscesses can be an initial clinical manifestation in asymptomatic pulmonary arteriovenous fistula. This possible association should be borne in mind in cases of brain abscesses of unexplained etiology.

Prediction and evaluation of brainstem function by auditory brainstem responses in patients with uncal herniation.

Serial measurements of auditory brainstem-evoked responses (BERs) were conducted in 15 patients with supratentorial mass lesions. Significant prolongation of the latency of wave V BERs, which originates in the inferior colliculus, occurred when the intracranial pressure (ICP) approached 30 mmHg. In four of five patients whose BERs were measured before pupillary changes, a significant lengthening of wave V latency was observed prior to clinical manifestation of uncal herniation. These results suggest that immediate medical or surgical decompression of ICP should be performed when ICP approaches 30 mmHg with significant prolongation of wave V latency.

Persistent trigeminal artery associated with brainstem infarct--case report.

A 47-year-old male presented with a sudden onset of right hemiparesis and numbness of the left face. Magnetic resonance imaging demonstrated a lacunar infarct in the ventral pons. Cerebral angiography demonstrated a persistent trigeminal artery (PTA) anastomosing the left internal carotid artery to the distal basilar artery. Bilateral vertebral arteries and the basilar artery below the PTA junction were extremely hypoplastic. The bilateral posterior communicating arteries were embryonic. The posterior fossa circulation was almost independent from the circle of Willis. The poor vascular supply to the posterior fossa probably caused the brainstem infarct.

Aneurysm of the cervical internal carotid artery associated with Marfan's syndrome--case report.

An aneurysm of the internal carotid artery associated with Marfan's syndrome occurred in a 23-year-old female with a 2-year history of a pulsating lesion in the left neck, which progressively increased in size. Left carotid angiography demonstrated a giant saccular aneurysm at the origin of the internal carotid artery. The aneurysm was excised and end-to-end anastomosis performed without postoperative morbidity.

Fatal subarachnoid hemorrhage due to ruptured infundibular widening of the posterior communicating artery--case report.

A 57-year-old male suffered a fatal subarachnoid hemorrhage due to ruptured infundibular widening of the internal carotid-posterior communicating artery junction, confirmed by autopsy. Infundibular widening is a preaneurysmal or aneurysmal lesion and indicates angiographic follow-up and control of blood pressure when identified.

Primary choroid plexus papilloma of the foramen magnum--case report.

A 50-year-old male presented with a choroid plexus papilloma in the foramen magnum manifesting as dysesthesia in the right hand and severe headache. Magnetic resonance imaging clearly showed that the tumor was located in the cerebellomedullary cistern, without extension into the fourth ventricle. However, differentiation from hemangioblastoma or foramen magnum tumor was difficult by neuroimaging. Intraoperative observation found the tumor was located extraventricularly and attached to the choroid plexus of the foramen of Magendie. The tumor was grossly totally resected. Histological examination proved the tumor was a choroid plexus papilloma without malignancy. His neurological deficits resolved almost completely.

Emerging symptoms of growing skull fracture after secondary trauma in an adult--case report.

A 20-year-old female presented with dysphasia and slight hemiparesis following a head trauma, who had a non-treated growing skull fracture which had remained asymptomatic for about 18 years, despite an encephalocele in the left parietal region. Neuroimaging demonstrated secondary brain damage and herniated brain resulting in gliosis. Electroencephalography revealed epileptic discharge in the affected region. Dural repair and cranioplasty resolved her neurological deficits. Early corrective surgery should be performed for growing skull fracture to prevent secondary brain damage.

Intramedullary spinal cord arteriovenous malformation with hematomyelia without subarachnoid hemorrhage--case report.

A 36-year-old male presented with an intramedullary spinal cord arteriovenous malformation with hematomyelia but without subarachnoid hemorrhage, manifesting as lower body sensory impairments and leg weakness. Magnetic resonance imaging was used to localize the lesion. Myelotomy allowed excision of the lesion and his sensory impairments improved.

[Spontaneously cured carotid-cavernous fistula verified by angiography--report of a case (author's transl)].

A case of spontaneously cured carotid-cavernous fistula has been reported in details with a review of literatures. Seven cases verified by angiography have been described so far in the literature. Spontaneous cure has been revealed within 6 months after the initial examination in 5 out of 7 cases by follow up angiography, and has occurred in five women of middle age. The presented case was a 45 year-old female who has suffered from the exophthalmos associated with disturbed eye movements of two months duration. On January 2, 1977, the carotid angiography demonstrated a c--c fistula and an oval aneurysm of the middle cerebral artery on the right side. The exopthalmos was slowly decreased with the conservative treatment after two months. The c--c fistula was not demonstrated by the angiography carried out on March 10, 1977, and was not revealed thereafter by follow up studies.

[The role of brain-stem vasomotor centers on the neurogenic control of the neurogenic control of cerebrovascular tonus. Part 1: In special reference to cerebral blood volume and intracranial pressure].

An increase in cerebral blood volume (CBV) due to a decrease in cerebrovascular tonus has been though to be a major factor in the cause of acute brain swelling. It has been reported that the dorsomedial nucleus of the hypothalamus (DM), one of the brain-stem vasomotor centers, regulates cerebrovascular tonus. The DM and other vasomotor centers, such as the midbrain reticular formation (MBRF) and the reticular formation of the medulla oblongata (MORF), are connected through a series of nerve fibers. This experiment was designed to clarify the neurogenic control of the DM, MBRF, and MORF on cerebrovascular tonus. Using fifty-six cats, unilateral and bilateral DM(A 1.2, L2.0, H-10.0), MBRF (A4.0, L4.0, H0), and MORF (P10.0, L2.5, H-9.0) were coagulated stereotaxically with the condition of 15-10 mA for 1 minute. The lesions in the DM and MBRF were enlarged by increasing the current intensity of electrical coagulation. The effects of the increase on a number of simultaneously coagulated lesions were examined. Changes in systemic blood pressure (BP), intracranial pressure (ICP), and CBV were continuously recorded. Temporary increases in ICP (mean increase 16 mmHg, n = 14) and CBV were observed after unilateral coagulation of the DM. These increases were associated with transient systemic hypotension. The changes lasted only for approximately 5 minutes. The changes that occurred in ICP and CBV as a result of unilateral coagulation in the MBRF were almost the same as those that occurred after coagulation of the DM. In the latter case, the duration of the change was approximately 6 minutes with a mean increase of 12 mmHg (n=12).(ABSTRACT TRUNCATED AT 250 WORDS)

[The effect of brain-stem vasomotor centers on the neurogenic control of cerebrovascular tonus--Part 3. The effects of destruction and stimulation of the brain-stem on intracranial pressure in acute subarachnoid hemorrhage].

The purpose of the present study is to clarify the effects of destruction and stimulation of the brain-stem on intracranial pressure (ICP) in experimentally induced subarachnoid hemorrhage (SAH). Using 23 cats, blood pressure (BP), ICP and local cerebral blood volume (CBV) were continuously measured. Acute SAH was produced by injection of autogenous blood (3 to 7 ml) into the cisterna magna. The animals were divided into two groups. Group A: those in which hypothalamic dorsomedial nucleus (DM) and reticular formation of the midbrain (MBRF) were coagulated bilaterally one hour after SAH and Group B: in addition to the procedure of Group A, reticular formation of the medulla oblongata (MORF) was electrically stimulated bilaterally. In 19 out of 23 cats of both groups, transient small increases in ICP and CBV were observed during coagulation and/or stimulation of DM, MBRF and MORF respectively in the animals whose ICP remained approximately 20 mmHg or below and progressive increase in ICP was never evoked. In 3 animals of Group A whose ICPs remained high at more than 20 mmHg, sequential destruction of DM and MBRF induced stepwise increase in ICP to 40 to 80 mmHg and consequently resulted in acute brain swelling. In 1 animal of Group B whose ICP fluctuated around 20 to 40 mmHg, biphasic increase in ICP to 100 mmHg was repeatedly evoked by stimulation of MORF. It is concluded that in the condition of increased ICP produced by SAH, lesions in the DM and MBRF and stimulating condition of MBRF may result in acute brain swelling.

[The role of brain-stem vasomotor centers on the neurogenic control of cerebrovascular tonus. Part 2: The effect of stimulation of the medullary reticular formation on cerebrovascular tonus].

Acute brain swelling has been proposed to be caused by vasomotor paralysis secondary to disruption of metabolic and/or neurogenic control of cerebrovascular tone. In previous experiments, acute brain swelling was produced by stimulation of the reticular formation of the medulla oblongata (MORF) with destruction of the dorsomedial nucleus of the hypothalamus (DM) and the reticular formation of the midbrain (MBRF) in 2 (out of 56) animals. The purpose of the present study is to clarify the effect of stimulation of the MORF on cerebrovascular tone. Using 32 cats, blood pressure (BP), intracranial pressure (ICP) and cerebral blood volume (CBV) were continuously measured. The animals were divided into 4 groups: those in which the ICP was normal (Group A), those in which the ICP increased after subarachnoid hemorrhage (Group B), those which underwent superior cervical ganglionectomy (Group C) and those in which the spinal cord was transected at the C2 level (Group D). In all animals, the MORF was stimulated after the DM and MBRF were destroyed. Thirty minutes after cessation of stimulation, the BP was increased again by injection of angiotensin II until it reached the same level as with MORF stimulation. The vasomotor index (VI), defined by delta ICP/delta BP, was calculated and compared between the two situations. BP, ICP and CBV increased simultaneously immediately after MORF stimulation. In 29 out of the 32 animals, ICP increased abruptly from 2 to 48 mmHg and after ten seconds or more decreased gradually. The BP rose about 50 mmHg more slowly than the ICP. After cessation of MORF stimulation, BP, ICP and CBV returned to the control value.(ABSTRACT TRUNCATED AT 250 WORDS)

[Angioimmunoblastic T-cell lymphoma with hyperplastic germinal centers].

We report a case of angioimmunoblastic T-cell lymphoma (AITL) in a 48-year-old Japanese male. Characteristic clinical manifestations of AITL such as fever, weight loss, skin rash, general lymphadenopathy, Coombs test positivity, and polyclonal hypergammaglobulinemia were present. Histopathologically, the nodal architecture was preserved and germinal centers were, if anything, hyperplastic, which was unusual for AITL. Diagnostic clear cells were absent. Intrafollicular tingible-body macrophages were markedly increased. In the interfollicular zone, proliferation of UCHL-1 + immunoblasts was evident, and high-endothelial postcapillary venule-type vessels were increased. The T-cell receptor gene (C beta 1) was clonally rearranged. Based on these findings, a diagnosis of AITL with hyperplastic germinal centers was made. Six courses of CHOP were administered and no signs of relapse were noticed about two years after diagnosis.