Application of Continuous ICP Monitoring in Deciding Shunt Surgery in Patients with Hydrocephalus

The authors present their experience with continuous intracranial pressure(ICP) measurements in 6 adult patients suffering from hydrocephalus. The patients showed atypical symptoms and signs and/or were in complicated situations to decide CSF shunt surgery. The role of ICP measurements in a decision of shunt surgery has been found in those cases. The ICP pattern of plateau waves in conjunction with B-waves could be regarded as an indication of shunt therapy in the light of clinical results.

Brain Tumor Immunology: Part II : Immunotherapy of Malignant Brain Tumors

The prognosis of patients with malignant brain tumors has improved only slightly despite the combined use of surgery, radiation therapy, and chemotherapy. Immunotherapy offers some possibilities and hopes as a fourth modality for the treatment of cancers although it is still in the early stages of development. It is possible to classify immunotherapy within four generally accepted modalities : 1) restorative or nonspecific immunotherapy 2) adoptive immunotherapy 3) passive immunotherapy 4) active immunotherapy. The techniques of recombinant DNA, genetic engineering, cell fusion and hybridoma production, and molecular biology will make these therapeutic approaches more successful and as the clinical applications expand the skillful cancertherapist will become increasingly familiar with these treatments and the problems associated with their use.

Effect of Rapid and Slow Infusions of the Mannitol on Regional Cerebral Blood Flow and Brain Edema in Focal Brain Compression of Cats

The aim of the present study has been to examine the effect of mannitol on regional cerebral blood flow(rCBF) and brain edema both at normal and increased intracranial pressure and to determine which of two infusion methods, rapid infusion or slow infusion of mannitol, has better effect on brain compression. Thirty five adult cats weighting between 2.7 and 4.2 kg were used in this study. The animals were divided into four groups: Mannitol administered normal control(n=5), brain compression(n=10), rapid mannitol treated-brain compression(n=10) and slow mannitol treated-brain compression groups(n=10) respectively. A small balloon connected to a fine polyethylene tube was placed in the epidural space of the right frontal region through a small burr hole and inflated with on ml of distilled water in increment of 0.2 ml to simulate the expanding mass. The measurements of rCBF and electroencephalography(EEG) activity were carried out in each animal. Mannitol was given in bolus of 1g/kg body weight via the femoral vein and two methods of mannitol infusion were used as rapid infusion which was infused the mannitol within 3 min and slow infusion, infused within 15min. The rCBF was measured by hydrogen clearance method and the brain edema was measured by gravimetric technique. In brain compression group, the ICP rose immediately following brain compression to 133.00+/-9.49 mmH2O from 78.00+/-11.35 mmH2O and maintained the elevation during the experiment. Treatment with mannitol in brain compression animals, decreased the ICP at 5 min after infusion of mannitol, and the decreased ICP was maintained for one hour. Brain compression animals showed a significant reduction of rCBF by 38% and 46% in right parietal lobe at the 60 min and 120 min after brain compression, respectively. In mannitol treated brain compression animals, the administration of mannitol made the reduced rCBF increase to baseline value at 30 min after treatment and the increased rCBF value was maintained for one hour. There was generalized brain edema, as judged by a decreased specific gravity in the brain compression, which was maximal close to the brain compression site. The severity of the brain edema was less in the mannitol treated brain compression group than in brain compression group. This study demonstrated that there was no significant different effects between rapid and slow infusion of mannitol in brain compression.

Clinical Analysis of 27 Cases of Metastatic Spine Tumors

The authors analyzed 27 cases of metastatic spine tumors who had been treated at the Department of Neurosurgery of Catholic University Medical College during last 5 years. The results were summarized as follows: 1) The tumor was most common in 6th decade of age(40.7%), and the male to female ratio was equal. 2) The level of the involved spine was thoracic(51.9%), lumbosacral(25.9%), cervical(22.2%) in orders. 3) The most common histopathologic type of the primary focus was lung cancer(25.9%), and nexts were gastric cancer, cervix cancer, breast cancer in frequency. 33.3% of all cases were histologically undetermined. The level of the involved spine was not related to the primary cancer type. 4) The common clinical features were pain(70.4%), motor disturbance(33.3%), sensory disturbance(25.9%) and sphincter symptom(11.1%). In plain X-ray examination, pedicle destruction was most commonly found(40.7%), and all 4 cases of bone scanning showed multiple hot area. In myelography, extradural complete block of dye co lumn was found in 9 cases(60%), and a case showed finding of intradural-extramedullary block. Computerized tomography with water soluble contrast media, which can give a most accurate diagnostic information, showed destruction of the vertebral body(61.5%), pedicle(39.5%) and shadows of tumor compressing the spinal cord(38.5%). 5) 4 cases were receivd surgical treatment only and 8 cases were treated with radiation therapy. Surgery with radiation therapy was performed in 8 cases and 7 cases were treated with radiation therapy and chemotherapy. The results of treatment in 19 survivals were analyzed according to the neurologic function between before and after treatment. 8 cases(42.1%) were improved and 7 cases(36.8%) showed no change, and 4 cases(21.1%) were more worsened comparing to pre-treatment state.

Further Experience of Stereotaxic Urokinase Treatment in Spontaneous Intracerebral Hematoma

According to the general principle that a surgical procedure should be as atraumatic as possible several authors proposed stereotaxic urokinase treatment in spontaneous intracerebral hematomas. Authors presented 29 cases of spontaneous intracerebral hematomas which were managed with stereotaxic urokinase treatment including 10 cases of preliminary report on Journal of Korean Neurosurgical Society June 1986. 19 cases were basal ganglia hematomas with or without ventricular rupture, 4 cases were thalamic hematomas with ventricular rupture, 3 cases were subcortical hematomas and 3 cases were intraventricular hematomas. The outcome of the treatment was analysed by the location and amount of hematomas, and the degree of disability of patient on admission and discharge. The outcome was worst in thalamic hematomas than putaminal or subcortical hematomas, and poorer as the amount of hematoma increased. The outcome was bad also in the patient who showed poor neurologic condition on admission. Time requiring hematoma dissapperance with urokinase treatment was estimated by the short term follow up CT scanning. All of the patient except moribund cases showed complete disappearance of hematomas within 10 days after treatment, and mean period was 6.7 days. Rebleeding after the urokinase treatment was noted in 4 cases, which was 2 putaminal, one thalamic and one ventricular hematoma. The cause of rebleeding might be mechanical injury of catheter insertion or too strong negative pressure on aspiration. But in 1 case of intraventricular hematoma, the possible causative factor should be anticoagulant effect of urokinase on the injured vessel. With above result, we concluded that this procedure may be better and safer than conventional craniotomy especially in cases of high risky or elderly patient with deep seated intracerebral hematomas. But the efficacy and safety must be studied further with the exact experimental model of spontaneous intracerebral hematomas.

Effective of Naloxone on Cerebral Blood Flow in the Acute Stage of Experimentally Induced Subarachnoid Hemorrhage in Cat

The immediate fall in cerebral blood flow(CBF) and the early clinical picture following subarachnoid hemorrhage(SAH) correlate well with the prognosis of most of the patients. But the cause of this fall in CBF is not fully understood. Recently attention has been focused on the role of endogenous opiates in the pathogenesis of cerebral ischemia. This research was planned to observe the acute change of regional cerebral blood flow(CBF) in experimentally induced SAH, to investigate whether endogenous opiate plays a role in the mechanism of the acute reduction in CBF following SAH, and to document the therapeutic value of naloxone. We have studied the effects of naloxone, an opiate antagonist, on CBF, cardiovascular system, intracranial pressure (ICP) and electroencephalography(EEG) in pentobarbital anesthetized cats. Twenty - five adult cats were divided into four groups as follows : control group (group I; 5 caes), naloxone-treated control group (group II; 5 cats), SAH group (group III; 7 cats) and naloxone-treated SAH group (group IV; 8cats). The measurement of CBF was done by hydrogen clearance methods, and carried out every 20 minutes from the beginning to 140 minutes following SAH. Naloxone(10 mg/kg) was intravenously administered to cats, three times : 40, 80 and 120 minutes following SAH. The results were as follows : 1) We have induced SAH in 18 cats, in which 15 cats showed the immediate reduction in CBF following SAH(incidence rate : 83%). 2) Significant elevations in the mean arterial blood pressure(MABP : 141+/-10.7 to 146+/-12.3 mmHg) and ICP(19+/-3.5 to 21+/-3.9mmHg) were observed immediately after SAH, followed by reduction respectively to the levels of baseline value within 40 minutes after SAH. Naloxone had no significant influence on the changes in MABP and ICP. 3) Baseline values of CBF in group I and II were 44.5+/-6.9 to 50.1+/-5.4 ml/100g/min, and were not changed by naloxone. 4) Induction of SAH resulted in a significant reduction of blood flow to 34.8+/-5.9 to 38.4+/-5.6ml/100g/min(p<0.05), and the reduced value was not significantly changed through the experiment. Reduction in CBF was usually greater on the side of the lesion. 5) In group IV, the initial administration of naloxone made the reduced CBF increase to about 46 ml/100g/min(p<0.05), and the increased CBF value was maintained by the additional injections of naloxone. 6) Cats subjected to SAH exhibited progressive loss of amplitude and decreased frequency in EFG, which were improved by the administration of naloxone. These data suggest that endogenous opiate, which may cause decrease of cerebral metabolic rate and vasoconstriction, can play an important role in the mechanism of the acute reduction in CBF following SAH. Naloxone may induce increase in CBF by reversing the effects of endogenous opiate and its direct cerebral vasodilator properties.

A Case of Thoracic Disc Herniation Treated by Transthoracic Transpleural Approach

Thoracic disc herniation is uncommon and only represents 0.25% to 0.75% of all symptomatic disc lesions. The difficulty in diagnosis has been the one of the major problems in the treatment of thoracic disc herniation. But at now, the use of computed tomography with or without water soluble contrast media makes the diagnosis more acurate. Recently, we diagnosed a case of T4, T5 disc herniation by computed tomography with iopamidol. Operation by transthoracic, transpleural approach was done with microsurgical technique, and the result was good. The case is reviewed and other surgical techniques on the literature is discussed.

Effect of Focal Brain Retraction on the Regional Cerebral Blood Flow and the Electroencephalographic Activity in the Cat

The use of brain retractors, unavoidable method in operation of deep intracranial lesions, may lead to focal cerebral ischemia and thereby cause brain infarction. In such operation, the surgical microscope is commonly used to get good surgical field. However, as the time of operation becomes lengthened, it results in longer retraction of the brain and probable greater ischemic infarction. To estimate the risk of ischemic damage, the authors investigated the regional cerebral blood flow(rCBF) and the electroencephalographic(EEG) activity at different forces and durations of the brain retraction in the cat models simulating the frontal approach of the pituitary surgery. Twenty-six adult cats weighing from 2.4 to 4.5 kg were used in this study. The animals were divided into 3 groups : control(n=6), 20g-retraction(n=10), and 30g-retraction groups(n=10) respectively. The brain retraction was produced by applying the lead weight with the stainless steel retractor on the right frontal lobe through a craniectomy over the right frontal bone. The weight(20g or 30g) was supported with the pulley so that its long axis was perpendicular to the cortical surface, The measurements of rCBF activity were carried out in each animal before and immediately after brain retraction at 30 min, 60 min, 90 min, 120 min and 180 min after retraction. The results were as follows ; 1) After brain retraction, there were rise in intracranial pressure, bradycardia, elevation in blood pressure and alteration in respiration at 60 min after brain retraction. 2) Normal control flows(rCBF, ml/100g/min) were 39.7+/-6.1 in the right frontal, 37.8+/-2.6 in the left frontal, 37.5+/-3.6 in the right parietal and 38.8+/-4.1 in the left parietal lobes. 3) A considerable reduction in rCBF was demonstrated at 60 min after brain retraction. A reduction of rCBF to 40% of control flow(19.5+/-7.5ml/100g/min) was found at 60 min after retraction in the right frontal with the 20g-retractor. With the 30g-retractor, rCBF were reduced to 64% of control flow(13.3+/-6.8ml/100g/min) at 60 min and 90% of control flow(4.0+/-2.1 ml/100g/min) at 180 min after retraction in the right frontal lobe. 4) A close correlation was found between EEG activity and rCBF changes, suggesting a threshold relationship. The changes of EEG activity began to be noted at the rCBF value of less than 20.0 ml/100g/min. A 50% suppression of the EEG activity appeared at the rCBF value of 4.0+/-1.2 ml/100g/min. It is concluded that EEG activity is secondarily is secondarily suppressed by reduction in local blood flow which is caused by local compression. It is advisable to retract the brain with the least force necessary and for the shortest time possible. It is also suggested to resect the brain partially before retraction to avoid irreversible ischemic infarction of the brain in consequence of forceful, longtime retraction in exploration of deep intracranial lesions.

Analysis of Operative Results in Pituitary Adenoma

The authors have reported on 34 patients with pituitary adenoma who underwent surgical treatment. The preoperative and postoperative clinical manifestations, size, and extension of tumor, therapeutic modalities and changes of endocrinological symptoms and hormonal values. In a series of 34 adenomas, 7(25%) were non-secreting and 27(79%) produced a hypersecretion syndrome; human growth hormone(5), prolactin(17), mixed GH and PRL type(3), corticotropic adenoma(2). The principal symptoms were endocrinological symptoms(74%), visual disturbance(59%) and headache(50%) on a admission. Vision improved in 90% of the patients. Normal menstruation returned in 35.3% of the prolactinoma. Endocrine cure was possible in 24% of prolactin-secreting and 40% of GH-secreting and 33% of mixed GH, PRL adenomas and not improved in corticotropic adenomas. The mortality rate was 0.6%. Postoperative radiation therapy appeared to play a greater role.

3 Cases of Intracranial Lipoma: Case Report

Intracranial lipomas are rare tumor which are usually found at or near the mid saggital plane, especially in the corpus callosum. 3 cases of intracranial lipomas, diagnosed by CT scanning, are presented. The first case was a lipoma involving the midline of occiput to the bilateral occipital lobes through the skull defect. There was a calcified area in this tumor. The second case presented a generalized convulsive seizure as clinical manifestation, and the lipoma was found to be located in the corpus callosum. In the third case, the lipoma was located near the third ventricle and the tumor was found incidentally after head trauma. The first case was operated and the tumor was completely removed, the others were managed with symptomatic treatment. The literature on this rare tumor is reviewed and discussed.

Intraoperative Visual Evoked Potential Responses to Preserve Vision in Operation with Sellar and Parasellar Lesions

Damage to the visual system is an unfortunate complication of surgery in the area of the optic nerve and chiasm. It is now possible to monitor the functional status of the visual system intraoperatively at regular intervals. We studied the patients during parasellar surgery to determine if this technique could be used to indicate potential danger to the visual system. Our objective was to determine if the visual evoked response was sensitive and dynamic enough to detect premoibid changes in the function of the visual system. This is accomplished by recording the Visual Evoked Potential Response to flash of light from light-emitting diodes goggle. 1) We studied two patients during sellar and parasellar surgery to determine if this technique could be used to indicate potential danger to the visual system. 2) It was benefit to determine if the intraoperative VEP was sensitive and dynamic enough to detect premorbid changes in the function of the visual system. 3) The VEP showed conduction was blocked when the optic nerve was manipulated and restored when the optic nerve was decompressed. 4) After the optic nerves were decompressed, VEP of nearly normal latency, amplitude and form was recorded. 5) Changes in the VEP pararell improvement of function after surgical removal of sellar and parasellar tumors. 6) Determination of improved nerve conduction permitted the prediciton of visual recovery during surgery.

Classification of Spontaneous Thalamic Hemorrhagy for Management and Prediction of Prognosis

65 patients with spontaneous thalamic hemorrhage(TH) diagnosed by CT scan were treated in Catholic Medical Center. Of total 340 patients with spontaneous intracerebral hemorrhage from 1980 to 1983, TH occured in 19.1%. In order to analyse prognosis and guideline of management we classified TH into 4 types with the topographic involvement of thalamus : Type I-the anteromedial TH in 3 cases(4.8%) showed no specific correlation between symptoms and site of hematoma. The prognosis was good with medical treatment alone. Type II-the posterolateral TH in 23 cases(35.2%), mainly spreaded into the internal capsule and the midbrain. Aphasia was one of the main clinical features and the prognosis was worse with both conservative and surgical treatment than those of type I and III. Type III-the dorsal TH in 26 cases(40%), often extended to the lateral ventricle and were localizing in the thalamic area. Emotional change was more occasionally indicated. Type IV-the massive TH in 13 cases(20%), was extensively involved in the thalamus and spreaded to all direction. Symptoms and signs were various and surgery was not indicated because the prognosis was poor. Aphasia was noted in the left TH, but right-hemisphere cortical dysfunction were found mainly in the right TH. The prognoses of the patients with aphaia and/or right hemisphere cortical dysfunction were poorer than those of the patients without. We consider that the patients in type II or III with aphasia and/or right-hemisphere cortical dysfunction should be managed with EVD or stereotaxic urokinase therapy for better neurological outcome.

Cerebral Blood Flow and Somatosensory Evoked Potentials Following Cerebral Hemispheric Injury and Effect of Mannitol: An Experimental Cat Model

Since every component of the evoked responses are considered to be related to topographically specific neural structures, it is possible that the location and severity of brain dysfunction could be accurately defined by careful analysis of evoked responses. The main objective of this experiment was to replicate some of the mechanisms involved in human brain injuries in cat and observe the effect of focal hemispheric brain injury on regional cerebral blood flow(rCBF) and somatosensory evoked potential(SEP) and to evaluate the effects of mannitol on them. Thirty adult cats weighing 2.5 to 4.2kg, were used in this study. The animals were divided into 3 groups of 10 cats each:(1) mild injury, (2) severe injury and (3) mannitol treated severe injury group. A mild injury was produced by moving the drill along a predetermined pathway through the right parietal hole at 50 cycle per minute for 2 seconds and a severe injury was produced in a similar fashion at 200 cycle per minute for 3 seconds. A mannitol treated group was produced in a same method as the severe injury group. The rCBF and SEP measurements were performed immediately after injury in each animal, at 30 minutes, 60 minutes and the final flow at 90 minutes by Pasztor(1973) hydrogen clearance technique. The results obtained were as follows. 1) After focal cerebral hemispheric injury, there were rapid rise in intracranial pressure, bradycardia, changes in blood pressure and marked alteration in respiration which are neurogenically mediated. 2) Normal control flows(rCBF, ml/100g/min) were 30.7+/-5.9 in right frontal, 35.2+/-6.7 in right parietal, 27.9+/-6.8 in left frontal, and 35.2+/-7.3 in left parietal lobes. 3) Sequential changes of the rCBF after focal cereral hemispheric injury were as follows. (1) Mild focal hemispheric injury resulted in a reduction of flow to 30% of control flow(RF:18.8+/-3.7, RP:25.0+/-7.8ml/100g/min) at injury resulted in a reduction of flow to 30% of control folw(RF:18.8+/-3.7, RP:25.0+/-7.8ml/100g/min) at injury site after immediate injury. (2) Severe focal hemispheric injury resulted in a reduction of flow to 50% of control flow(RF:20.4+/-10.9, RP:18.8+/-7.6ml/100g/min) at injury site after immediate injury. (3) Mannitol-treated severe injury resulted also in a reduction of flow to 50% of control flow at the injury site after immediate injury, but at 90 minutes the flow was 75% of the control flow. 4) A close correlation was found between cortical-evoked potentials and flow, suggesting a threshold relationship both on injury and non-injury areas. (1) The SEP was present shortly after injury though markedly altered in shape and the early components(No, N1) of the SEP were suppressed first. (2) It was also noted that the amplitude of the SEP was much smaller, perhaps due to direct ijury on the injured area. (3) The SEP disappeared if the rCBF in either hemisphere fell below 15ml/100gm/min. 5) It might be inferred from these results that adequate flow was vital for the preservation and return of electrical activity following brain injury.

Regional Spinal Cord Blood Flow on Cord Traction:An Experimental Cat Model

The tethered cord syndrome is a clinical entity manifested by progressive motor and sensory changes in the legs, incontinence, back or leg pain, and scoliosis in young children. Based on remarkable neurological improvement after release of cord tension by sectioning the filum, it might be concluded that the neurological deficit was effected by cord tethering. The main objective of this experiments was to elucidate the pathophysiology involved in the tethered cord by observing the effect of tethered cord on regional spinal cord blood flow(rSCBF) and somatosensory evoked potentials(SEPs) and define a threshold relationship between SEP and rSCBF. Thirty adult cats, weighing 2.7 to 4.2kg were used in this study. The cats were divided into three groups as follows: Control group=non-tethered(10 cats), 5g-traction group=cord traction with 5g weight(10 cats). 10g-traction group=cord traction with 10g weight(10 cats). The rSCBF and SEP measurements were performed immediately after cord traction in each animal, at 30, 60, 90, 120 minutes and the final rSCBF at 3 hours by the hydrogen clearance technique. The results obtained were as follows: 1. Traction and resulted in a reduction of flow to 30%(6.0+/-1.4ml/100g/min) of normal control spinal cord flow(18.2+/-1.6ml/100g/min) at adjacent area of traction(L1) in 5g-traction group and 18%(3.5+/-0.7ml/100g/min) of normal control flow in 10g-traction group during the cord traction for 3 hours. 2. From 30 minutes to 3 hours following the cord traction, there was a tendency toward marked reduction of the blood flow at the adjacent area(L1, T10) in 10-traction group. 3. The rostral area of spinal cord away from traction was less influenced in a reduction of blood flow following the cord traction. 4. A close correlation was found between spinal evoked potentials and flow suggesting a threshold relationship. 1) The SEP was present shortly after traction though marked by altered in shape and suppressed. 2) The SEP responses progressively decreased in latency at the adjacent distal area of the cord during traction, however less changed in shape at the rostral area of the cord. 3) The SEP suppressed in shape if the blood flow in spinal cord was below 14ml/100g/min. 4) The neuronal dysfunction caused by tethered cord could be due to impairment of blood flow. It is assumed that prolonged neuronal dysfunction may lead to structural damage of the neuron.

CT Guided Stereotaxic Biopsy for the Differential Diagnosis of Brain Lesions

Some intracranial masses are usually treated following a presumptive diagnosis based on the clinical picture and neurological studies but in some instances a proven histological diagnosis might alter the method of treatment as well as affect the prognosis. Open surgical biopsy however might cause serious neurological deficit in many of these patients however a stereotaxic approach might avoid such problems. For the correct three dimensional target localization on CT scan we developed nearly artifact free simplified CT interface frame that accurately interface between the CT scanner and the stereotasic instrument makes it possible to take biopsies at exact and with low risk. In 10 patients CT interfaced stereotaxic biopsy of brain lesions were performed. 100% accurate histological diagnosis was obtained and helped considerably in planning further therapy. The localization error was less than 0.04mm and no significant complications occured in these patients.

A Case of Frontoethmoidal Meningoencephalocele

Meningoencephalocele in the anterior part of the cranium is a rare congenital anomaly and has been sparsely reported in the neurologic literature. Recently we encountered a case of bilateral frontoethmoidal meningoencephalocele in a 3-year-old otherwise healthy boy. The cranial ends of the tumors were amputated by bifrontal craniotomy and dural defect was tightly repaired with Neodura. The external portions of the tumors were excised at the second stage and double-limbed YV shaped canthoplasty was performed. Postoperatively, the patient recovered uneventfully without any complication.