PubMed Health⌕ Search

Biomedical subjects

F Momma

Publications and source records attributed to F Momma.

At least 19 recordsLinked to original sources
PubMed2001

[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.

Diagnosis, Differential↗
PubMed1997

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.

Choroid Plexus↗
PubMed1994

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.

Adult↗
PubMed1992

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.

Adult↗
PubMed1992

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.

Brain Stem↗
PubMed1992

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.

Adult↗
PubMed1990

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.

Arteriovenous Fistula↗
PubMed1988

Assessment of reversible cerebral ischaemia in man: intraoperative monitoring of the somatosensory evoked response.

Central conduction time (CCT) has been monitored in 37 patients undergoing temporary arterial occlusion in aneurysm surgery. 17 patients had internal carotid, 17 had middle cerebral, and 4 had basilar artery occlusion. Internal carotid or middle cerebral artery occlusion lasting less than 12 minutes has not been associated with postoperative morbidity, in any case without appreciable change in CCT after occlusion. Prompt prolongation of CCT was warned the surgeon, but CCT prolongation up to 10 ms could occur without permanent neurological deficit, except in one Grade 4 patient. 10 of 18 patients who lost the N 20 cortical potential showed postoperative neurological deficit, which was promptly recoverable in 7 patients. The speed of loss or recovery of N 20 enabled a patients's prognosis to be predicted. Irrecoverable postoperative deficit is unlikely if the N 20 takes longer than 4 minutes to disappear, to reappears within 20 minutes after recirculation.

Evoked Potentials, Somatosensory↗
PubMed1988

Changes in pyramidal tract conduction with experimental brain-stem ischaemia in the monkey.

The effect of graded ischaemia on intracranial nerve fibre conduction has not previously been studied quantitatively. We measured pyramidal tract (PT) discharges evoked by electrical stimulation of the ipsilateral motor cortex, together with local blood flow (by hydrogen clearance), in the internal capsule and ventral pons of baboons anaesthetised with alpha-chloralose. Changes in conduction time and amplitude of the motor volley were monitored over this PT segment as it was subjected to progressive ischaemia in controlled stages. Conduction time increased significantly, with attenuation of the volley, at average brain-stem tissue flows below 30 ml/100 g/min. Using paired stimuli, we demonstrated relative refractory and supernormal characteristics of PT conduction. In mild ischaemia, the conduction time of the test response decreased, much more than with single stimulation, and in denser ischaemia it increased, relatively more so at smaller inter-stimulus intervals. The data demonstrate the impairment of conduction in a population of CNS axons with reduced local blood flow and indicate that the transmission of relatively rapid sequences of impulses would be the first aspect of conduction to suffer in ischaemia prior to conduction block.

Animals↗
PubMed1988

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.

Animals↗
PubMed1988

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.

Adenosine Triphosphate↗
PubMed1988

The effect of intravenous lidocaine on experimental brain edema and neural activities.

A series of experiments was conducted to clarify the effect of intravenous administration of lidocaine on brain water content, local cerebral blood flow (lCBF), and neural recovery in brain injury induced by exposure of the cat's cerebral surface to the air. The injury produced ischemia and edema in the cortex and white matter without direct damage of the cortex. Lidocaine (3.0 mg/kg) was given intravenously for 30 minutes immediately after air exposure and thereafter at the rate of 2 mg/kg/hour. Twelve hours after exposure, lidocaine significantly suppressed cortical ischemia and edema; however, it had no effects in the white matter. The electrophysiologic activities of the cortex and white matter which were assessed by the direct cortical response and somatosensory evoked response were significantly preserved by lidocaine compared with nontreated animals. The results of this experiment demonstrate that intravenous lidocaine has a significant beneficial effect on cortical ischemia and electrophysiologic activities of the cortex and white matter in injured brain.

Animals↗
PubMed1987

Intra-operative electrocochleography to monitor cochlear potentials during acoustic neuroma excision.

Intra-operative electrocochleography (ECochG) was used in an attempt to monitor the action potential of the cochlear nerve during acoustic neuroma surgery in 14 patients with useful pre-operative hearing. Five patients had ECochG potentials preserved and yet only three could hear when tested audiometrically later. Of those losing the potentials intra-operatively all were subsequently deaf and the pattern of waveform loss allowed determination of the probable cause of hearing loss. Complete excision of the tumour was achieved in each case regardless of the ultimate effect on the AP as it was not felt justified to risk subsequent recurrence. In common with other studies one of the best prognostic factors for these preservation of hearing was found to be the size of the tumour.

Adult↗
PubMed1987

Clinical evidence supporting a subthalamic origin of the P15 wave of the somatosensory evoked potentials to median nerve stimulation.

Both somatosensory (SSEPs) and brain-stem auditory evoked potentials (BAEPs) were recorded in 3 patients with localized lesions in the thalamus or brain-stem. In one patient with a right thalamic cystic tumour there was a significant interhemispheric difference in the central conduction time (CCT), but the N14-P15 interval was not affected on either side and BAEPs showed normal wave latencies and interpeak latencies (IPLs). The second patient had a colloid cyst of the third ventricle in which central herniation had occurred resulting in 'locked-in' syndrome. The P15 peak was absent on one side and markedly prolonged in latency on the other. BAEPs showed neither wave IV nor V on either side. The third patient had compression of the right posterior rostral pons by a metastatic tumour, resulting in significant prolongation of the CCT on the side of the tumour because of increase in the N14-P15 interval. Both I-V and III-V interpeak latencies were significantly prolonged bilaterally without prolongation in I-III IPL in this case. There was a correlation between the electrophysiological abnormalities of P15 and of BAEP wave V. These results suggest that the origin of the P15, which is usually recorded as a far-field potential, may be in the subthalamus or the upper part of the brain-stem.

Adult↗
PubMed1987

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.

Adult↗
PubMed1987

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.

Adult↗