Culturing Successfully Adult Schwann Cells from Peripheral Nerve of Rats

PURPOSE: Schwann cells are difficult to isolate from adult mammalian peripheral nerves because of the abundant connective tissue and the highly differentiated state of the cells, particularly those involved in the formation of myelin. It has been shown that in vivo, both neurons and Schwann cells are conditioned by a nerve lesion, speeding up the Schwann cell proliferation and the neuronal regeneration. In this study with adult rat peripheral nerves, we report that a conditioning lesion increases Schwann cells and of cells which successfully attach to a tissue culture striatum. METHODS: The study was done with Sprague-Dawley male rats(250-300 g). Their left sciatic nerves were exposed, severed at the sciatic notch and deflected. After 14 days, with 20 mm segments the nerves were excised from the distal stump of the conditioned sciatic nerves. Schwann cells were cultured in RPMI-1640 media. The identity of the cells was verified with antibody staining using S-100. RESULTS: The lesion evoked a progressive and significant increase in the number of cells obtained as early as 48 hr of the plating, until day 12. Decreasing the duration of enzyme digestion to 3 and 4 hrs markely increased the number of attached Schwann cells. The peak numbers of attached Schwann cells was observed between day 12 and day 14 of the plating. Most attached Schwann cells had typical oval-shaped cell bodies, with prominent nuclei and bipolar cell extensions, resulting in overall spindle shapes. CONCLUSION: Our findings indicate that a conditioning lesion enables us to isolate and culture adult Schwann cells successfully from the peripheral nerves of rats.

Temperature Difference Between the Brain and Axilla in Patients Under Hypothermia

OBJECTIVE: The brain temperature is about 0.4-1 degrees C higher than that of the other peripheral body area. But most of these results have been obtained in normothermic condition. The objective of this study is to evaluate the temperature difference between the brain and axilla, in patients under hypothermia. METHODS: Sixty-three patients(37 women and 26 men) who underwent craniotomy with implantation of the thermal diffusion flowmetry sensor were included in this study. The temperature of the cerebral cortex and axilla was measured every 2 hours, simultaneously. The patient group was divided according to axillary temperature hyperthermia(over 38 degrees C), normothermia(36-38 degrees C) and hypothermia(under 36 degrees C). Total 1671 paired sample data were collected and analyzed. RESULTS: The temperature difference between the cerebral cortex and the axilla was 0.45+/-1.04 degrees C in hyperthermic patients, 0.97+/-1.1 degrees C in normothermic patients and 1.04+/-0.81 degrees C in hypothermic patients. The temperature difference has statistical significance in each group(unpaired t-test, p<0.05). CONCLUSION: From our study the temperature difference between the brain and the axilla in hypothermic condition increased more than that of normothermic state. And in hyperthermic condition, the temperature difference decreased.

Percutaneous Vertebroplasty with Polymethymethacrylate in the Treatment of Osteoporotic Vertebral Body Compression Fractures: Preliminary Report

No abstract available.

A Clinical Analysis of the Ventriculoperitoneal Shunt with Programmable Shunt Divice

CSF shunting procedures are widely employed in the treatment of hydrocephalus and other disturbances of the dynamics of CSF such as a rachnoid cyst and syrinx. The relative simplicity of this operation with respect to other neurosurgical procedures is matched by a high incidence of complications. Many kinds of shunt devices have been developed to reduce complications. Yet, this operation frequently requires surgical revision. Traditional shunts were primarily designed to manage hydrocephalus by regulating intracranial pressure. Those devices, in some circumstances, can cause to underdrain or overdrain CSF and may need a surgical revision to adjust the pressure Authors have treated 28 patients with the disturbaces of CSF dynamics using pressuread justable valve system (Codman-Medos p rogrammable Hakim valve system). Two patients had arachnoid cysts and the others had hydrocephalus with various etiologies. Subdural hygroma was developed in 5 patients and underdrainage was observed in 9 patients on CT scan. By adjusting the pressure, Authors achieved clinical improvements without a need for surgical revision. The optimum pressure was 97.4+17.4mmHO for the patients with hydrocephalus with various etiologies in adults. In conclusion, the incidence of shunt revision by using this shunt device for the treatment of hydrocephalus and arachnoid cysts was decreased.

Anterior Ceervical Interbody Fusion: Comparison Study between Simple Fusion, Locked and Non-locked Plating Systems

The use of metallic plate and screws in the anterior cervical fusion has become generally acceptable and popular. Mainly, there are two different plating systems available. However, there has been few attempts to compare their clinical results with and without a plating system or between two different systems in a single series of clinical study. The authors reviewed 117 patients who underwent anterior cervical fusion during the period of January 1992 to September 1996. Simple fusion without a plating system was applied in 55 cases(group 1), a bicortical non-locked plate screw system in 25(group 2), and a monocortical locked plate screw system in 37(group 3). The average follow-up period was 13. 2 months. In group 1, twenty-two patients(40%) with fracture-dislocation or corpectomy required a rigid brace such as halo brace and Minerva cast for 3 months postope ratively and seven patients(13%) experienced graft complications, mainly graft extrusion. In group 2 and 3, the patients required only soft b races for 4 to 8 weeks and no patients experienced serious graft complications like ones in group 1 but, instead two patients with screw breakages, two back-outs and one non-union were observed. In comparison of the clinical complications such as hoarsness, there were no significant differences between the groups. In conclusion, the plating system in anterior cervical fusion appears to be safe despite the facts that mo re technical demands are required during surgery. It also provides better postoperative stability in the spine and permits earlier ambulation without a rigid brace. A monocortical locked plate screw system appears to have less hardware failures and better su rgical results than a bicortical non-locked plate screw system.

A Clinical Comparison between Epidural Pressure Measurements and Intraventricular Pressure: Technical Note

OBJECTIVE: Measurement of intracranial pressure(ICP) is important in patients at risk of raised ICP. To evaluate the usefulness of measuring epidural pressure measurements for the estimation of intracranial pressure, we studied the relationship between epidural pressure and ventricular pressure. PATIENTS AND METHODS: From Nov. '97 to Jul. '98, 10 patients of extraventricular drainage(Group A) and 12 patients of decompressive craniectomy(Group B) are included in this study. Simultaneous recording of intracranial pressure (ICP) from an air-pouch epidural pressure monitoring system and a ventricular catheter was compared. RESULTS: The epidural pressure group(Group A) showed marked high epidural pressure(32.6+/-13.4mmHg) compared with those of intraventricular pressure, but in decompressive craniectomy group(Group B) shows nearly the same values(2.1+/-6.9mmHg). CONCLUSIONS: On the basis of the available comparison between these two methods of measuring intracranial pressure, in the light of the data we had established and the importance of ICP monitoring in neurosurgical critical care, intradural monitoring technique appears to be our measuring method of choice.

Continuous Monitoring of Regional Cortical Blood Flow in Aneurysm Surgery

OBJECTIVE: The tolerance and the safety of temporary arterial occlusion in aneurysm surgery are variable among patients because of individual variations of their collateral circulation. We recorded continuous intraoperative regional cortical blood flow(rCoBF) with thermal diffusion flowmetry(TDF) in patients with aneurysmal subarachnoid hemorrhage to determine a safe time limit for temporary occlusion in relation to rCoBF. PATIENTS AND METHODS: From Oct. '97 to Sep. '98, 40 patients with cerebral aneurysm at anterior cerebral artery(ACA) or middle cerebral artery(MCA) were included in this study. The TDF probe was placed over the cortex which was supplied by corresponding arteries. For data analysis, we included only the patients with Hunt-Hess grade I or II on admission. RESULTS: The total occlusion time of the proximal parent artery in 24 patients was on average 21.8 minutes, ranging between 9 minutes and 68 minutes. The lowest rCoBF in relation to temporary occlusion time in patient with excellent outcome was as follows: 0ml/100mg/min for 13 minutes and 6ml/100mg/min(11% of basal rCoBF) for 18 minutes in the middle cerebral artery and bilateral anterior cerebral arteries, respectively. The multiple regression equation regarding safe time for temporary clipping was as follows: safe time = 5.5 + 0.06 X rCoBF intra + 0.25 X rCoBF pre. And reperfusion time for the full recovery of rCoBF was within 4 minute in most cases, except some no-reflow cases. CONCLUSION: In our study with proper brain protection, a safe time limit for temporary occlusion was calculated 18 minutes even at 0ml/100mg/min in the MCA and this technique seems to be very useful to detect a continuous real time change of rCoBF during aneurysm surgery.

Wernicke's Encephalopathy Induced by Hyperemesis Gravidarum: Steroid Therapy and FLAIR MR Technic

A 39-year-old woman developed Wernicke's encephalopathy in the sixteenth week of her pregnancy after eight weeks of severe nausea and vomiting. Because of her protracted severe vomiting, she had inpatient treatment with intravenous dextrose and electrolytes without thiamine. In her fourteenth week of pregnancy, she began showing neurologic symptoms such as dizziness, tinnitus, hearing impairment, nystagmus and ataxia. To rule out possibility of brain stem lesions, MRI of brain was performed. MRI showed tectal lesions as well as bilateral symm-etric midline lesions along the third ventricle and cerebral aqueduct. Further evaluate for these lesions, FLAIR(fluid-attenuated inversion-recovery) MR imaging was performed. Based on her clinical symptoms and FLAIR MR imaging, she was diagnosed as Wernicke's encephalopathy. Combined therapy with vitamin B1(50mg/day) and steroid(met-hylprednosolone 1g/day) was immediately started. Two days later, her neurologic symptoms improved. FLAIR imaging technique allows easier identification of specific periventricular distribution of the lesions. The preventive steroid therapy may have resulted in beneficial outcome on Wernicke's encephalopathy.

Estrogen and Progesterone Receptors and Cell Proliferative Activities in Meningiomas

It has been suggested that hormonal manipulation may be proved to be an alternative mode of therapy, especially in cases of unresectable or recurrent meningiomas, and the effect of the endocrinological therapy may be influenced by the presence or absence of hormone receptors in meningiomas. The assessment of biological behavior of the tumors is important to plan postoperative adjuvant therapy and follow-up schedules, and the evaluation of cell proliferative activities has been known to be valuable in prediction of recurrence and aggressiveness of meningiomas. The purpose of this study was to investigate the status of hormone receptors and cell proliferative activities, and to determine the relationship between nucleolar organizer regions(AgNORs) and flow-cytometric methods in evaluating cell kinetics of meningiomas. Cytosolic estrogen receptors(ER) and progesterone receptors(PR) were studied in meningiomas removed from 43 patients. Cell proliferative index(PI) based on tumor cell-cycle stage(%S+%G2M) was calculated by flow-cytometic studies of paraffin- embedded meningioma tissue blocks, and the mean number of AgNORs per cell was measured by silver-colloid staining technique. Evaluable results of hormone receptors, PI, and AgNORs could be obtained in 40, 37, and 41 of original meningiomas, respectively. Significant levels of ER(ER+) were found in 27.5% of the patients, while significant PR levels(PR+) were detected in 40%, PR+ were found in 14(40%) of 35 benign meningiomas but in all of the one atypical and one malignant meningiomas. It appeared with the anaplastic histological features of necrosis or brain infiltration had higher incidence of PR+ than the tumors without them, and the higher the cell proliferative activities, the higher the incidence of PR+PI of two atypical and one malignant menigiomas were rather higher but the number of AgNORs of them were significantly higher than thoes of thirty benign meningiomas(p<0.05). The tumors with the histological feature of mitotic figures had proliferative activities than those without mitotic figures(p<0.05). Thirty-three percent of the benign meningiomas had the PI value higher than 30%, and about twelve percent of the benign meningiomas had the AgNORs greater than 2.5 per cell. a linear correlation was demonstrated between PI and the number AgNORs(r=0.71, p<0.001). These results suggest that antiprogesterone therapy may be of use in treatment of highly proliferative or aggressive meningiomas, and the number of AgNORs showing correction with PI may reflect the cell kinetics well and be of value in predicting recurrence of meningmas and in planning postoperative adjuvant therapy.

Supraclavicular Approach to a Lesion in the Cervico-Thoracic Junction

A lesion in the cervico-thoracic junction can be of interest to neurosugeons, not only because its incidence is quite low, but also because there is not a published proper anterior approach. Currently the authors have experienced two cases of degenerative disease and one case of traumatic dislocation of the cervico-thoracic junction, in which the main lesions were located in the interspace or posterior portion of vertebral bodies at the junction between the cervical and thoracic spines and an anterior approach to the lesions should be considered. A supraclavicular approach has applied to these cases, by which a good surgical field was obtained. Furthermore the surgical results were good without any serious complication.

A case of Unusual Trigeminal Neurinoma

We reported a case of huge cystic trigeminal neurinoma. The patient was 35 year old female with trigeminal nerve dysfunction and hemiparesis. The computed tomography disclosed a huge cystic low density mass at the temporal base and suprasellar cistern that extended to cerebellopontine cistern through the tentorium, and enlargement of Meckel's cave on coronal scan. Through the infratemporal and retromastoid suboccipital approach, the cystic content was aspirated and cyst wall was removed. The cystic change of neurinoma may be due to mucoid degeneration and liquifaction.

Diffuse Axonal Injury : Changes of Cerebral Blood Flow, Intracranial Pressure and Evoked Potentials

Fifteen cases of diffuse axonal injury(DAI) brought about by nonmissile head injury in humans are analyzed. All cases were subjected to comprehensive clinical studies such as measurement of cerebral blood flow by SPECT, continuous intracranial pressure monitoring and multimodality evoked potentials(MEPs). In the patients with DAI, a high incidence of low cerebral perfusion and abnormal MEPs. especially auditory evoked potentials, were found, with high incidence of high velocity traffic accident injury mechanism. On the other hand, a low incidence of increased intracranial pressure was found and dehydrating agents such as glycerol and mannitol did not exert a beneficial influence upon the clinical courses or the outcomes. The outcome of the patients with DAI depended upon the duration of coma and whether or not brain stem signs were noted.

Somatosensory Evoked Potentials in Ventricular Enlargement of Experimental Hydrocephalus

We investigated the somatosensory evoked potentials(SEPs) changes and subsequent changes of the ventricular enlargement in different stages of kaolin-induced hydrocephalus. 8 week-old fifty five cats weighing 900g to 1300g, were studied in this experiment. These animals were divided into 2 groups ; a normal control(5 cats), kaolin-induced hydrocephalic groups(50 cats). The kaolin-induced hydrocephalic groups were subdivided into 5 subgroups of 10 cats each ; kaolin induced 1,2,4,6 and 8 weeks hydrocephalic groups after an intracisternal injection of the kaolin. At the each stage of the kaolin-induced hydrocephalic animals, the following parameters were obtained ; somatosensory evoked potentials(SEPs) and the size of enlargement of the ventricles at the each stage of 1,2,4,6 and 8 weeks after intracisternal kaolin injection. The results were as follows: 1) A significant elevation of the intracranial pressure(ICP) was observed in 2 weeks after kaolin injection and peak value(ICP : 10.2+/-0.9mmHg) in 4 weeks after kaolin injection. 2) The mean latencies of these wave components in somatosensory evoked potentials(SEPs) responses were 6.27+/-0.12 msec in Po, 8.41+/-0.25 msec in No, and 12.55+/-0.36 msec in P1 and the mean central conduction time(P1-P0) was 6.10+/-0.16 msec in the normal control animals. 3) Changes of amplitude and latency in SEPs were more prominent in 4 weeks after kaolin injection and progressively prolonged latencies of each wave components and CCT were resulted in 6 and 8 weeks after kaolin injection. 4) In hydrocephalic animals, the size of the ventricle(septum pellucidum (SP)-caudate nucleus(CN) distance) was moderately increased to 5.19+/-0.43mm in 1 week after kaolin injection and continued to increased in maximum size up in the 4th week after injection. However there was no further increase in ventricular size after 4th weeks. 5) A close correlation was found between SEPs and ventricular enlargement at the each stage of kaolin-induced hydrocephalic animals. In conclusion, it is assumed that the detection of SEPs in hydrocephalus is a quite valuable prognostic tool to evaluate the functional integrity of the nerve conduction system near the paraventricular area which might be involved in ventricular enlargement.

Effect on the Regional Cerebral Blood Flow and Biomechanical Factors in Ventricular Enlargement of Experimental Hydrocephalus

To evaluate the biomechanical changes and cerebral blood flow in hydrocephalic brain, this study was designed to determine the regional cerebral blood flow(rCBF; frontal cortex and periventricular area), the pressure volume index(PVI) and the resistance to the absorption of cerebrospinal fluid(Ro) in different stages of the kaolin-induced hydrocephalus. Fifty five 8 week-old cats, weighing 900g to 1300g were used in this experiment. The experimental animals were divided into 2 groups ; a normal control(5 cats), and kaolin-induced hydrocephalic groups(50 cats). The kaolin-induced 1,2,4,6 and 8 weeks hydrocephalic groups after intracisternal injection of the kaolin. The rCBF was measured by hydrogen clearance technique and the PVI and Ro were determined by the technique of bolus manipulation of CSF. A significant elevation of the intracranial pressure(ICP) was observed in 2 weeks after kaolin injection and peak value(ICP=10.2+/-0.9mmhg) was obtained in 4 weeks after Kaolin injection. The significant decrease in rCBF were revealed in both frontal cortex and periventricular area of kaolin-induced hydrocephalic cats. The PVI was significantly increased from the normal value 0.77+/-0.02ml to 1.60+/-0.16ml at 4 weeks after kaolin injection and increased to 2.12+/-0.34ml at 6 weeks after kaolin injection. Ro was significantly decreased from the normal value 90.6+/-1.3mmHg/ml/min to 36.8+/-4.3mmHg/ml/min at 4 weeks after kaolin injection and further decreased to 6.2+/-1.9mmHg/ml/min at 8 weeks after kaolin injection. In Hydrocephalic cats, the size of the ventricle(septum pellucidum-caudate nucleus distance) continued to increase in size up to 9.40+/-0.7mm at the 4th week. However, there was no further increase in ventricular size after the 4th week. This study indicated that kaolin-induced hydrocephalic cats led to dramatic changes in volume-buffering capacity expressed as PVI, coupled a reduction in the Ro. The absorptive defect and also loss of volume-buffering capacity are not sufficient to cause progressive ventricular enlargement. It is assuming that some microcirculatory impairment in the brain parenchyma is playing an important role which facilitates ventricular expansion with changes of biomechanical property of the brain.

The Pre-operative Assesment for Shunt Surgery in Normal Pressure Hydrocephalus

Normal pressure hydrocephalus(NPH) is defined as a combination of dementia, gait disturbance and/or urinary incontinence, hydrocephalus on C-T scan, with a normal intracranial pressure. The clinical effect of CSF shunting in patients with this syndrome is sometimes striking but generally only 50-60% of the shunted patients benefit from the treatment. So many pre-operative investigations are performed including clinical examination, computed tomography, R-I cistrnography, T1/2 calculated from ventricular volume pressure curve and lumbar drainage. Among the pre-operative investigations, the effect of preoperative lumbar drainage was the most reliable indicator of NPH. The possible mechanisms of improved case are proposed. The differential diagnosis of primary brain atrophy and NPH can be made by the effect of pre-operative lumbar drainage.

Evaluated Value of Multimodality Evoked Potential in Vascular Lesions of the Thalamus

We reviewed the cases of 9 patients with vascular lesions in thalamus, 5 hemorrhage and 4 infarctions that were confirmed clinical and CT findings. Generally CT scan and clinical datas proved to be helpful to the diagnosis and prognosis to thalamic lesion. However, these findings are not exactly correlated to prognosis of patients. We can gain more informative factors to our patients for Multimodal evoked potential examination (MEP) to analysis. Especially in our cases, MEP findings proved to be the most effective results in the determinations of the prognosis. We review the literature and discuss the treatment and discuss the treatment and prognosis in thalamic lesion. Emphasis is placed on the current and optimal method of the evaluation of prognosis in thalamic lesions using MEP combined with the finding of CT scan and clinical status.