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OBJECTIVE: At present, gold-standard technique of cervical cord decompression is surgical decompression and fusion. But, many complications related cervical fusion have been reported. We adopted an extended anterior cervical foraminotomy (EACF) technique to decompress the anterolateral portion of cervical cord and report clinical results and effectiveness of this procedure. METHODS: Fifty-three patients were operated consecutively using EACF from 2008 to 2013. All of them were operated by a single surgeon via the unilateral approach. Twenty-two patients who exhibited radicular and/or myelopathic symptoms were enrolled in this study. All of them showed cervical cord compression in their preoperative magnetic resonance scan images. RESULTS: In surgical outcomes, 14 patients (64%) were classified as excellent and six (27%), as good. The mean difference of cervical cord anterior-posterior diameter after surgery was 0.92 mm (p<0.01) and transverse area was 9.77 mm2 (p<0.01). The dynamic radiological study showed that the average post-operative translation (retrolisthesis) was 0.36 mm and the disc height loss at the operated level was 0.81 mm. The change in the Cobb angle decreased to 3.46, and showed slight kyphosis. The average vertebral body resection rate was 11.47%. No procedure-related complications occurred. Only one patient who had two-level decompression needed anterior fusion at one level as a secondary surgery due to postoperative instability. CONCLUSIONS: Cervical cord decompression was successfully performed using EACF technique. This procedure will be an alternative surgical option for treating cord compressing lesions. Long-term follow-up and a further study in larger series will be needed.
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Humanos , Descompresión , Descompresión Quirúrgica , Estudios de Seguimiento , Foraminotomía , Cifosis , Compresión de la Médula Espinal , EspondilosisRESUMEN
OBJECTIVES: To identify the better option of treatment, we compared the surgical results and efficacy of combined anterior-posterior approach versus posterior fixation alone. METHODS: During a 10 years period from 2002 to 2011, 111 patients with thoracolumbar burst fracture was surgically managed at our institute. 25 patients were managed by a combined anterior-posterior surgery and 86 patients were managed by posterior fusion alone. Radiographs were repeated at 3, 6, 12 and 24 months after operation. Radiologic outcome was evaluated by measuring Kyphotic angulation and vertebral height and the clinical outcome was evaluated by visual analogue scale (VAS) score comparison. RESULTS: The average Cobb's angle difference between immediate post operative and last follow up was 15.0degrees in combined 360-degree fusion group and 7.5degrees in posterior surgery alone group. A corrections of vertebral body height between immediate post operative and last follow up was 2.27 mm in 360-degree fusion group while 0.59 mm in posterior fixation group. The VAS score decreased from 8.4 to 2.2 after post operation 24 months in 360-degree fusion group and the posterior surgery alone group decreased 9.3 to 6.2 after post operation 24 months. CONCLUSION: The combined anterior-posterior approach resulted in less deterioration of the kyphotic angle postoperatively and improvement of vertebral height (sagittal index). Clinical outcome was also better in the combined group.
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Humanos , Estatura , Estudios de SeguimientoRESUMEN
While extruded disc fragments are known to migrate anteriorly, posteriorly, or laterally to the theca sac, posterior migration of the fragments is relatively rare and sudden onset of cauda equina syndrome (CES) caused by the migration is extremely rare. The authors experienced a case of CES that was manifested abruptly with sudden paraplegia caused by posterior migration of the lumbar intervertebral disc. A 74-year old man, who had no prior significant neurologic signs or trauma history, visited our emergency center with paraplegia of both lower extremities occurring suddenly when awakened. On magnetic resonance image (MRI) findings, we could detect ruptured disc herniation with severe lumbar stenosis at the L2-3 level. We performed an emergent decompression, and the right posterior migrated disc fragments at L2-3 were intraoperatively observed. The patient was fully recovered himself on the follow up after 3 months of the operation. In conclusion, early operation can result in better outcome in acute paraplegia caused by the posterior migrated disc fragments.
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Humanos , Cauda Equina , Constricción Patológica , Descompresión , Urgencias Médicas , Estudios de Seguimiento , Disco Intervertebral , Desplazamiento del Disco Intervertebral , Extremidad Inferior , Espectroscopía de Resonancia Magnética , Manifestaciones Neurológicas , Paraplejía , PolirradiculopatíaRESUMEN
OBJECTIVE: Epidural venous varicosity (congestion of the epidural vein) is rarely introduced as an influential factor of clinical symptoms. However, there are several studies suggesting that epidural venous varicosity results in neurologic symptoms. We would like to highlight evidence that epidural venous varicosity results in neurologic symptoms and the relation between epidural venous varicosity and neural structure observed during the surgery. Based on our experiences, we also propose a new classification of epidural venous varicosity. METHODS: 29 patients with symptomatic lumbar stenosis received microsurgical decompression via partial hemilaminectomy. The authors retrospectively reviewed all recorded intraoperative pictures and categorized patterns of venous varicosities with relationship to neural structures. RESULTS: Type A is conditions in which epidural veins are dilated but located parallel to the nerve root on the lateral side of the nerve root and thus do not compress the nerve root. Type B is conditions in which varices are located on the anterior lateral side of the nerve root to compress the nerve root. Type C is conditions in which varices are encircled around the nerve root and compressing the nerve root. CONCLUSION: Epidural venous varicosity is observed in most lumbar stenosis patients with clinical symptoms. Of the types, the types of epidural venous varicosity compressing nerve structures were Type B and Type C. All epidural venous varicosities were removed regardless of classification during operations. Most patients showed relief in clinical symptoms after the operation. We thought to epidural venous varicosity as a factor that causes clinical symptoms of lumbar stenosis.
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Humanos , Constricción Patológica , Descompresión , Descompresión Quirúrgica , Espacio Epidural , Claudicación Intermitente , Manifestaciones Neurológicas , Radiculopatía , Estudios Retrospectivos , Estenosis Espinal , Várices , VenasRESUMEN
OBJECTIVE: The purpose of this study was to evaluate the results obtained in patients who underwent staged 360-degree fusion with posterior fusion following anterolateral fusion for unstable thoracolumbar burst fractures. METHODS: The authors performed 360-degree fusion for thoracolumbar burst fractures in 21 patients between 2006 and 2010. We reviewed the medical records and follow-up data including pre- and postoperative neurological status, spinal canal compromise, segmental kyphotic angulations, complications, visual analogue scale (VAS) pain scores, and revision surgery rates. RESULTS: The mean computed tomography-measured preoperative spinal canal compromise was 55.9+/-20.7%. The segmental kyphotic deformity measured 20.2+/-4.4degrees preoperatively and had been corrected to 4.5+/-2.8degrees postoperatively. The mean vertebral body height loss of 57.4+/-6.9% improved significantly to 1.2+/-0.7% at the final follow-up examination. The mean preoperative VAS pain score of 8.2+/-0.8 improved to 1.5+/-0.6 at discharge. There were no cases of vascular complication, neurological deterioration, or revision surgery. CONCLUSION: Unstable burst fracture of thoracolumbar spine managed by staged posterior fusion and anterolateral interbody fusionis effective for kyphosis correction, significant canal decompression, pain reduction, maintaining stabilization and neurological improvement.
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Humanos , Estatura , Anomalías Congénitas , Descompresión , Estudios de Seguimiento , Cifosis , Registros Médicos , Canal Medular , Fracturas de la Columna Vertebral , Fusión Vertebral , Columna VertebralRESUMEN
OBJECTIVE: The definition of empty sella syndrome is 'an anatomical entity in which the pituitary fossa is partially or completely filled with cerebrospinal fluid, while the pituitary gland is compressed against the posterior rim of the fossa'. Reports of this entities relating to the brain tumors not situated in the pituitary fossa, have rarely been reported. METHODS: In order to analyze the incidence and relationship of empty sella in patients having brain tumors, the authors reviewed preoperative magnetic resonance imaging (MRI) of 72 patients with brain tumor regardless of pathology except the pituitary tumors. The patients were operated in single institute by one surgeon. There were 25 males and 47 females and mean patient age was 53 years old (range from 5 years to 84 years). Tumor volume was ranged from 2 cc to 238 cc. RESULTS: The overall incidence of empty sella was positive in 57/72 cases (79.2%). Sorted by the pathology, empty sella was highest in meningioma (88.9%, p = 0.042). The empty sella was correlated with patient's increasing age (p = 0.003) and increasing tumor volume (p = 0.016). CONCLUSION: Careful review of brain MRI with periodic follow up is necessary for the detection of secondary empty sella in patients with brain tumors. In patients with confirmed empty sella, follow up is mandatory for the management of hypopituitarism, cerebrospinal fluid (CSF) rhinorrhea, visual disturbance and increased intracranial pressure.
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Femenino , Humanos , Masculino , Encéfalo , Neoplasias Encefálicas , Síndrome de Silla Turca Vacía , Estudios de Seguimiento , Hipopituitarismo , Incidencia , Presión Intracraneal , Imagen por Resonancia Magnética , Meningioma , Hipófisis , Neoplasias Hipofisarias , Carga TumoralRESUMEN
OBJECTIVE: The current literature implies that the use of short-segment pedicle screw fixation for spinal fractures is dangerous and inappropriate because of its high failure rate, but favorable results have been reported. The purpose of this study is to report the short term results of thoracolumbar burst and compression fractures treated with short-segment pedicle instrumentation. METHODS: A retrospective review of all surgically managed thoracolumbar fractures during six years were performed. The 19 surgically managed patients were instrumented by the short-segment technique. Patients' charts, operation notes, preoperative and postoperative radiographs (sagittal index, sagittal plane kyphosis, anterior body compression, vertebral kyphosis, regional kyphosis), computed tomography scans, neurological findings (Frankel functional classification), and follow-up records up to 12-month follow-up were reviewed . RESULTS: No patients showed an increase in neurological deficit. A statistically significant difference existed between the patients preoperative, postoperative and follow-up sagittal index, sagittal plane kyphosis, anterior body compression, vertebral kyphosis and regional kyphosis. One screw pullout resulted in kyphotic angulation, one screw was misplaced and one patient suffered angulation of the proximal segment on follow-up, but these findings were not related to the radiographic findings. Significant bending of screws or hardware breakage were not encountered. CONCLUSION: Although long term follow-up evaluation needs to verified, the short term follow-up results suggest a favorable outcome for short-segment instrumentation. When applied to patients with isolated spinal fractures who were cooperative with 3-4 months of spinal bracing, short-segment pedicle screw fixation using the posterior approach seems to provide satisfactory result.
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Humanos , Tirantes , Estudios de Seguimiento , Fracturas por Compresión , Cifosis , Estudios Retrospectivos , Fracturas de la Columna VertebralRESUMEN
OBJECTIVE: Hydrocephalus is one of the major complications following spontaneous subarachnoid hemorrhage (SAH). However, the risk factors of the hydrocephalus after SAH are not still well known. This study was focused on verification of the causal relationships between the development of hydrocephalus and SAH. METHODS: The patients who developed hydrocephalus after rupture of aneurysms were studied. To obtain prognostic factors regarding to hydrocephalus, several parameters such as age, sex, hypertension, location of aneurysm, existence of intraventricular hemorrhage (IVH) and intracerebral hemorrhage (ICH), Glasgow coma scale (GCS), Hunt-Hess SAH classification & Fisher Grade on admission and the ratio of frontal horn of lateral ventricle diameter to skull inner table diameter at this level (FH/ID) were studied retrospectively. RESULTS: The development of hydrocephalus following SAH is multifactorial. The age, IVH, FH/ID ratio were related to hydrocephalus in analysis. There is a low clinical correlation between sex, hypertension, location of aneurysm, existence of ICH, GCS, Hunt-Hess SAH classification, Fisher Grade on admission and hydrocephalus. CONCLUSION: Knowledge on risk factors related to the occurrence of hydrocephalus may help guide neurosurgeons in the long-term care of patients who have experienced aneurysmal SAH.
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Animales , Humanos , Aneurisma , Hemorragia Cerebral , Clasificación , Escala de Coma de Glasgow , Hemorragia , Cuernos , Hidrocefalia , Hipertensión , Ventrículos Laterales , Cuidados a Largo Plazo , Estudios Retrospectivos , Factores de Riesgo , Rotura , Cráneo , Hemorragia SubaracnoideaRESUMEN
OBJECTIVE: Hydrocephalus is one of the major complications following spontaneous subarachnoid hemorrhage (SAH). However, the risk factors of the hydrocephalus after SAH are not still well known. This study was focused on verification of the causal relationships between the development of hydrocephalus and SAH. METHODS: The patients who developed hydrocephalus after rupture of aneurysms were studied. To obtain prognostic factors regarding to hydrocephalus, several parameters such as age, sex, hypertension, location of aneurysm, existence of intraventricular hemorrhage (IVH) and intracerebral hemorrhage (ICH), Glasgow coma scale (GCS), Hunt-Hess SAH classification & Fisher Grade on admission and the ratio of frontal horn of lateral ventricle diameter to skull inner table diameter at this level (FH/ID) were studied retrospectively. RESULTS: The development of hydrocephalus following SAH is multifactorial. The age, IVH, FH/ID ratio were related to hydrocephalus in analysis. There is a low clinical correlation between sex, hypertension, location of aneurysm, existence of ICH, GCS, Hunt-Hess SAH classification, Fisher Grade on admission and hydrocephalus. CONCLUSION: Knowledge on risk factors related to the occurrence of hydrocephalus may help guide neurosurgeons in the long-term care of patients who have experienced aneurysmal SAH.
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Animales , Humanos , Aneurisma , Hemorragia Cerebral , Clasificación , Escala de Coma de Glasgow , Hemorragia , Cuernos , Hidrocefalia , Hipertensión , Ventrículos Laterales , Cuidados a Largo Plazo , Estudios Retrospectivos , Factores de Riesgo , Rotura , Cráneo , Hemorragia SubaracnoideaRESUMEN
We report a case of hyper vascular metastatic thyroid carcinoma of the jugular fora-men simulating a glomus jugulare tumor. Computed tomography(CT) revealed areas of irregular lytic bony destruction of the left jugular foramen, as well as characteristic in vasion routes of a glomus jugulare tumor. Magnetic resonance(MR) imaging and angiography demonstrated a hypervascular mass similar to a glomus tumor.
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Angiografía , Tumor del Glomo Yugular , Glomo Yugular , Tumor Glómico , Neoplasias de la TiroidesRESUMEN
Moyamoya disease is a rare obstructive cerebrovascular disease characterized by a cerebral angiographic picture of bilateral stenosis or occlusion of main cerebral arteries with an abnormal vascular network at the base of the brain. Although its pathogenesis is not clear, there is extensive evidence that this disease has tendency to show inheritance and familial occurrence. We have experinced such two cases of moyamoya disease. One was 4-year-old boy who had a history of TIA and bilateral hemiparesis(CaseI) and another was 8-year-old boy. The older brother of the Case I had unilateral symptom. They were treated with EDAS and split duroence-phalosynangiosis and had good results in their neurologic and postoperative angiographic state.
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Niño , Preescolar , Humanos , Masculino , Encéfalo , Arterias Cerebrales , Constricción Patológica , Enfermedad de Moyamoya , Hermanos , TestamentosRESUMEN
Amajor role in sustaining tumors like gliomas has been attributed to growth factors. Many questions remain unanswered about how such external signals are transduced into a transformed phenotype. Growth factors such as PDGF and epidermal growth factor(EGF) activate PLC, and this activation requires the intrinsic tyrosine kinase activity of the growth factor receptor. There are only a few reports on PKC activity in astrocytoma cells, especially in human glioma cells. We focused on signal transduction of phospholipase C(PLC) and phospholipase D(PLD) in human glioma cells. In this study, using genistein and calphostin C, the regulation of PLC, PLD, and PKC was investigated. The results are as follows; 1) Genistein is a selective inhibitor of PDGF-induced PLC- and PLD activation in T98G glioblastoma cells but not in Hs 683 glioma cells. 2) Calphostin-C stimulates PLC and PLD, possibly through a PKC-independent pathway in both T98G and Hs 683 cells. 3) Both genistein and calphostin-C inhibit glioma cell proliferation, indicating that the pathway for activation of PLC and PLD is not relevant to the pathway of cell proliferation in glioma cells.
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Humanos , Astrocitoma , Proliferación Celular , Genisteína , Glioblastoma , Glioma , Péptidos y Proteínas de Señalización Intercelular , Fenotipo , Fosfolipasas , Proteínas Tirosina Quinasas , Transducción de Señal , Fosfolipasas de Tipo CRESUMEN
Cerebellar hemangioblastoma comprises 2% of all brain tumors and 7% 10% of all posterior fossa tumors. It can arise in isolation("sporadic cases") or as a major manifestation of von Hippel-Lindau(VHL) disease, a well known autosomal dominant inherited tumor syndrome. Only 5-30% of these tumors are due to VHL disease. However, cerebellar hemangioblastoma occurs in younger patients, is often multiple and recurrent, and has a poorer prognosis than sporadic cases. We present a case of a 26-year-old woman with a right cerebellar hemangioblastoma, which recurred from a left cerebellar hemangioblastoma resected four years previously. Further evaluation established the diagnosis of VHL disease by demonstrating a cystadenoma in the pancreas and an omental cyst. Recently, the von Hippel-Lindau disease gene has been identified as a tumor suppressor gene and has been mapped to the short arm of chromosome 3(3p 25-26). Its absence or a defect in its structure is responsible for predisposition to the disease.
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Adulto , Femenino , Humanos , Brazo , Neoplasias Encefálicas , Cistoadenoma , Diagnóstico , Genes Supresores de Tumor , Hemangioblastoma , Neoplasias Infratentoriales , Páncreas , Pronóstico , Enfermedad de von Hippel-LindauRESUMEN
Hemangioblastoma is one of the benign tumors in the central nervous system. It is often associated with von Hippel-Lindau disease(VHL disease), a well known autosomal dominant hereditary tumor syndrome. We have experienced three cases of hemangioblastoma associated with von Hippel-Lindau disease in a same family, mother(case 1, 58 years old), son(case 2,19 years old, dead) and daughter(case 3, 17 years old). All of them had cerebellar hemangioblastomas. Renal cyst was associated in the case of mother, but not in the son or daughter. Hemangioblastoma associated with von Hippel-Lindau disease frequently occurres in multiple regions such as cerebellum, spinal cord, medulla oblongata. Also it is frequently presented with renal cell carcinoma, pheochromocytoma, cyst in pancreas, kidney and liver, and epididymal cystadenoma. The age of onset of von Hippel-Lindau disease in the second generation was younger than that of the first generation in this family.
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Humanos , Edad de Inicio , Carcinoma de Células Renales , Sistema Nervioso Central , Cerebelo , Cistoadenoma , Hemangioblastoma , Riñón , Hígado , Bulbo Raquídeo , Madres , Núcleo Familiar , Páncreas , Feocromocitoma , Médula Espinal , Enfermedad de von Hippel-LindauRESUMEN
A61-year-old head-injured patient exhibited acute onset of paraplegia during hospital in-care. Review of radiographs showed an occult linear transverse fracture line between the T11 and T12 vertebrae. An MRI scan performed after paraplegia showed compression of the spinal cord by a bony fragment. This case report presents a rare but devastating complication of an occult fracture at the T-L junction in patient with ankylosing spondylitis which was considered less significant due to more severe head injury. Thorough clinical and roentgenographic examination of the entire vertebral column is recommended in patients with ankylosing spondylitis who have sustained injury. Even if minor spinal trauma occurs in such clinical setting, the condition should be managed as a spinal fracture with potentially serious neurologic complications.
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Humanos , Traumatismos Craneocerebrales , Fracturas Cerradas , Imagen por Resonancia Magnética , Paraplejía , Médula Espinal , Fracturas de la Columna Vertebral , Columna Vertebral , Espondilitis AnquilosanteRESUMEN
Mesenchymal chondrosarcoma is a rare tumor occurring in both bone and soft tissues and exhibits characteristics of a highly malignant tumor. The authors experienced a case of mesenchymal chondrosarcoma ocurring in a 33-year-old man, which had invaded the soft tissues of the chest wall and had been incompletely removed, and recurred in the adjacent T10 vertebra 4 years later. The patient presented with severe back pain and paraparesis at admission. Radiographic studies of the vertebra showed an aggressive osteolysis of the vertebral body, pedicle, lamina, compression of the spinal cord, and soft tissue invasion. The tumor was totally removed by an anterior and posterior combined approach. The removed vertebral body was replaced with a titanium mesh cage, and the thoracic spine was stabilized by both anterior and posterior fixations with instruments. The pathological and the clinical characteristics of mesenchymal chondrosarcoma are discussed.
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Adulto , Humanos , Dolor de Espalda , Condrosarcoma Mesenquimal , Osteólisis , Paraparesia , Médula Espinal , Columna Vertebral , Pared Torácica , TitanioRESUMEN
We have recently operated directly on two patients with multiple aneurysms including cavernous carotid artery aneurysms(CCAAS). The pterional extradural transclinoidal and intradural transcavernous approach was used for CCAAS in two patients. Both two CCAAS could be clipped in Dolenc's anteromedial triangle between the optic nerve and the IIIrd nerve. There was no surgical mortality and morbidity was minimal. The combined extradural and intradural transcavernous approach was very useful and safe for direct clipping of CCAAS.
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Humanos , Aneurisma , Arterias Carótidas , Mortalidad , Nervio ÓpticoRESUMEN
The case of a 55-year-old male developed high flow carotid-cavernous fistula(ccF) after head trauma was successfully treated by a direct microsurgical approach to the cavernous sinus. The cavernous sinus was approached through Dolenc's anteromedial and paramedical triangle by a combined extradural and subdural route. A single tear in the wall of horizontal segment of the cavernous carotid artery was obliterated using Sugita clip while temporary clips were placed on the supraclinoid and the petrous portion of the internal carotid artery.
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Humanos , Masculino , Persona de Mediana Edad , Arterias Carótidas , Arteria Carótida Interna , Seno Cavernoso , Traumatismos Craneocerebrales , FístulaRESUMEN
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.
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Animales , Gatos , Absorción , Encéfalo , Hidrocefalia , Hidrógeno , Caolín , Valores de ReferenciaRESUMEN
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.