In order to observe the effects of various click polarity and stimulus rate on brainstem auditory evoked potentials (BAEPs), we measured the absolute latency, interwave latency and amplitude. Variations of IV-V wave complex in different stimulus rate and polarity were also observed. Observations were made on 50 normal subjects(32 males and 18 females) aged 8 to 56. The results are summarized as follows, 1. With rarefaction click stimulation, the absolute latencies of wave I and wave V were shortest, and wave I and wave III amplitudes were most increased as compared with condensation or alternating-polarity. 2. The absolute latencies of wave I and wave V were most prolonged and wave V amplitude was highest with condensation clicks. 3. I - III, III -V and I - V interwave latencies were not significantly changed between any of polarities. 4. By increasing stimulus rate from 10 click / sec to 50 click / sec, absolute and interwave latencies were significantly prolonged. Except wave V amplitude at condensation and alter-nating-polarity clicks, all wave amplitudes were decreased significantly. 5. The waveforms were classified into 5 types according to configuration of IV - V wave complex. At any conditions, type A and B were present most frequently. We proposed that if one is to employ only a single stimulus polarity, rarefaction clicks should be used because this will produce the earliest and largest wave I. Condensation can be used in those cases in whom rarefaction does not produce clar waveforms, or when wave V appears absent. The use of alternating-polarity clicks as the only mode of stimulation is discouraged because of the possibility of phase cancellations.
Brain Stem* ; Evoked Potentials, Auditory, Brain Stem* ; Humans ; Male

Recent studies have revealed that mossy fiber(MF) axons of dentate granule cells undergo synaptic reorganization in both electrical kindling models of temporal lobe epilepsy (TLE) and human TLE. This synaptic reorganization has been demonstrated by Timm histochemistry which selectively labels synaptic terminals of MF because of unusually high zinc content. Of MF. In electrical kindling model and human TLE Timm granules were distributed throughout the supragranular layer of dentate gyrus where they are not normally present. These supragranular Timm granules are regarded as MF synaptic reorganization. Kindling model of generalized epilepsy can be made by repeated intraperitoneal injections of subconvulsive dosage of pentylenetetrazol (PTZ). The present study is designed to test the hypothesis that MF synaptic reorganization might be developed in PTZ kindling model In this study, the supragranular Timm granules by Timm histochemistry were scored and depth EEG was recorded in dentate gyrus of various stages of PTZ kindling rats. The scores of supragranular Timm granules were 0. 33+0.17 in stage I seizure (n=9) ; 0. 38 + 0. 14 in stage II seizure (n=13) ; 0. 44 + 0. 18 in stage III seizure (n=9) ; 1. 40+0.16 in 3 consecutive or total 5-7 stage TV or V seizure (n=10) ; 1. 86+ 0.26 in 7-10 consecutive or total 10-15 stage IV or V seizure (n=7) ; 2.50+0.22 in 1215 consecutive or total 20-30 stage IV or V seizure (n=6) ; and 0. 30+0.15 in salinen controls (n=lo). Statistical analysis showed the supragranular Timm scorwere significantly higher in stage IV or V seizure than in control and in stage 1, I or, I seizure (p<0.05 ), and tended to increase with increasing numbers of stage IV or V seizure. Depth EEG recording from dentate gyrus showed 6-9Hz rhythmic waves in saline injected control, single or polyspikes or normal waves during stage I seizure, 4-6Hz slow waves or spike-waves complexes lasting 1-2 seconds during stage II seizure, 4-6Hz slow waves or spike-waves complexes lasting 3-6 seconds during stage III seizure, 8-15Hz spikes lasting over 10 seconds during stage IV seizure and 10-30HZ spikes lastmg over 20 seconds durmg stage V seizure The results demonstrate the development of MF synaptic reorganization and a sound correlation between MF synaptic reorganization and the progression of the kindlmg phenomenon in PTZ kindling models. These findings suggest that MF synaptic reorganization might be a critical event underlying the development and . Maintenance of kindling phenomenon and epileptic state.
Animals ; Axons ; Dentate Gyrus* ; Electroencephalography ; Epilepsy, Generalized ; Epilepsy, Temporal Lobe ; Humans ; Injections, Intraperitoneal ; Pentylenetetrazole* ; Presynaptic Terminals ; Rats* ; Seizures ; Zinc

The development of pentylenetetrazol (PTZ) kindling has been controversial, authors confirmed the development of kindling phenomenon in experimental rats following every second or third day intraperitoneal administration of PTZ(20-25mg/kg) to experimental rats and same amount of saline to control rats. The developmental stage of motor seizure could be categorized into five stages (stage I; clonic seizure of face and neck, stage II; clonic seizure of face, neck and forelimbs, stage III; clonic seizure of forelimbs and body with brief rearing, stage IV; falling and generalized clonic seizure, stage V; falling and generalized tonic-clonic seizure with tonic extension of hindlimbs). Linear regression analysis showed that the stages of motor seizure were increased with the number of PTZ injections (Y=0.1361X + 0.1943, p < 0.05). The persistence of kindling state was also observed after a 5-months pause of PTZ injection. This study suggested that PTZ kindling model in rats could be a good animal model of generalized epilepsy.
Animals ; Epilepsy, Generalized ; Forelimb ; Linear Models ; Models, Animal ; Neck ; Pentylenetetrazole* ; Rats* ; Seizures

BACKGROUND: The clinical and electroencephalographic differentiation of the mesial temporal lobe epilepsy (MTLE) and neocortical temporal lobe epilepsy (NTLE) may have a practical value. Until now, a few comparative studies reported some relatively minor differences between the two groups. We investigated the clinical history, interictal and ictal electroencephalographic (EEG) patterns to differentiate NTLE from MTLE. METHODS: Twenty two patients with medically refractory MTLE and fourteen patients with isolated neocortical lesions were recruited. The interictal and ictal scalp EEG patterns were compared in terms of the interictal EEG distribution patterns of epileptiform discharges, focal slow waves (ipsilateral/contralateral refers to side of pathology), and the frequencies of ictal discharges on EEG at seizure onset. RESULTS: Interictal EEG patterns of epileptiform discharges and focal slow waves were recorded most often at the ipsilateral or bilateral sphenoidal electrodes in both groups without significant differences. Ictal EEG onset with rhythmic theta waves was significantly more frequent in MTLE (72.3%) than in NTLE (36.7%), but ictal EEG onset with rhythmic alpha waves and those with rhythmic beta waves were significantly more frequent in NTLE (33.3%, 20.0%, respectively) than in MTLE (10.8%, 1.2%, respectively). Initial ictal EEG patterns appeared more frequently at the sphenoidal electrodes in both groups (MTLE:73.5%, NTLE:60.0%). Initial ictal EEG patterns of the bilateral hemisphere, ipsilateral hemisphere or ipsilateral diffuse temporal area were seen only in NTLE (16.7%, 3.3%, 10% respectively), but not in MTLE. CONCLUSIONS: This study showed that the initial ictal patterns and the frequency of ictal onset were significantly different in MTLE and NTLE. These differences could give a practical help in diagnosing MTLE and NTLE.
Electrodes ; Electroencephalography ; Epilepsy, Temporal Lobe* ; Humans ; Scalp* ; Seizures ; Temporal Lobe*

Niopam is a newer, nonionic, watersoluble contrast medium used predominately in cisternographic and myelographic studies with metrizamide lately. The former has fewer, less severe and shorter adverse reactions than the latter. Until now there were no reports on meningitis complicating Niopam CT cisternography or myelography. Now we present a case of aseptic purulent meningitis complicating Niopam CT cisternography.
Iopamidol* ; Meningitis* ; Metrizamide ; Myelography

Although some cases of benign positional vertigo are associated with a chronic ipsilateral sensorineural hearing loss, an association with simultaneous ipsilateral sudden deafness is rare. We report a 53-year old woman with sudden deaf-ness with simultaneous positional vertigo in the same ear characterized by benign paroxysmal positional vertigo of pos-terior semicircular canal type. After a modified Epley particle-repositioning maneuver, the patient's vertigo was resolved. Clinical and neuro-otologic evaluations suggested that the lesion responsible for this patient was probably located within inner ear rather than within the vestibulocochlear nerve. (J Korean Neurol Assoc 19(4):410~412, 2001)
Ear ; Ear, Inner ; Female ; Hearing Loss, Sensorineural ; Hearing Loss, Sudden* ; Humans ; Middle Aged ; Semicircular Canals ; Vertigo* ; Vestibulocochlear Nerve

BACKGROUND: Information on the long-term fate of patients with prosthetic valve is limited. Cerebral embolism is a major cause of late morbidity and mortality in patients with prosthetic valves even though recent prostheses are less thrombogenic and anticoagulants are administered. We investigated the long-term risk of the first ischemic and hemorrhagic stroke and effect of presumed risk factors on the development of stroke in patients with prosthetic valves. METHODS: In a retrospective study, 554 patients who survived the 30-days after cardiac valve replacement between June, 1985 and May, 1995 were included. End points were attacks of ischemic and hemorrhagic stroke. Risk of stroke at end points was calculated according to Kaplan-Meier method. The influence of several clinical variables on these stroke events was analyzed by univariate and mutivariate analyses. RESULTS: Thirty seven of 554 patients had 42 stroke events(34 ischemic stroke, 8 hemorrhagic stroke) during follow-up periods(mean: 52.9months). Six of these patients died from stroke. The cumulative stroke-free probability was 92.4% at 5years and 87.7% at 10years. The cumulative ischemic stroke-free probability was 93.7% at 5years and 89.4% at 10years. No or irregular use of anticoagulants was the only significant independent predictor(RR:4.99, 95%CI:2.01-12.41, p<0.01) of ischemic stroke. The cumulative hemorrhagic stroke-free probability was 98.7% at 5years and 98.1% at 10years. CONCLUSION: Regardless of the type of prostheses, patients with prosthetic valves, notably those without anticoagulants, are at high risk for ischemic stroke.
Anticoagulants ; Follow-Up Studies ; Heart Valves ; Humans ; Intracranial Embolism ; Mortality ; Prostheses and Implants ; Retrospective Studies ; Risk Factors ; Stroke* ; Thromboembolism

BACKGROUND: There exist considerable debates concerning about the effects of epilepsy surgery on cognitive function. To evaluate the effects of tailored anterior temporal lobectomy with amygdalohippocampectomy (ATLAH) on intelligence and memory, we compared the pre- and post-operative cognitive function in patients with mesial temporal lobe epilepsy (MTLE). METHODS: Thirty six patients who received unilateral tailored ATLAH from 1993 to 1997 and had been seizure-free for at least two years postoperatively were selected. Mean age at the time of surgery was 26.8 years and mean period of postoperative follow-up was 47 months. The change of cognitive function was assessed pre-and post-operatively using Korean Wechsler Adult Intelligence Scale (K-WAIS) and Rey memory test. We also assessed the correlation between the extent of hippocampal and lateral temporal cortical resection and cognitive changes respectively. RESULTS: In total patients (N=36), there was statistically significant improvement in performance IQ (PIQ, p<0.05), full scale IQ (FIQ, p<0.05), and auditory verbal learning test (AVLT). In the right temporal lobectomy group (N=16), improvement in PIQ, FIQ, and AVLT reached to statistical significance (p<0.05). In the left temporal lobecto-my group (N=20), improvement in PIQ was significant (p<0.05). In terms of the size of resection, there were tendencies that the cognitive function is more improved in patients with larger hippocampal resection (>2 cm) and in patients with smaller temporal cortical resection (4 cm). CONCLUSIONS: Patients became seizure free after tailored ATLAH may have improvement in performance IQ and full scale IQ. Right side resection, larger hippocampal resection, and smaller lateral temporal resection show better postoperative cognitive function. (J Korean Neurol Assoc 19(2):116~124, 2001)
Adult ; Anterior Temporal Lobectomy* ; Epilepsy ; Epilepsy, Temporal Lobe* ; Follow-Up Studies ; Humans ; Intelligence* ; Memory* ; Seizures ; Temporal Lobe* ; Verbal Learning

BACKGROUND: There exist considerable debates concerning about the effects of epilepsy surgery on cognitive function. To evaluate the effects of tailored anterior temporal lobectomy with amygdalohippocampectomy (ATLAH) on intelligence and memory, we compared the pre- and post-operative cognitive function in patients with mesial temporal lobe epilepsy (MTLE). METHODS: Thirty six patients who received unilateral tailored ATLAH from 1993 to 1997 and had been seizure-free for at least two years postoperatively were selected. Mean age at the time of surgery was 26.8 years and mean period of postoperative follow-up was 47 months. The change of cognitive function was assessed pre-and post-operatively using Korean Wechsler Adult Intelligence Scale (K-WAIS) and Rey memory test. We also assessed the correlation between the extent of hippocampal and lateral temporal cortical resection and cognitive changes respectively. RESULTS: In total patients (N=36), there was statistically significant improvement in performance IQ (PIQ, p<0.05), full scale IQ (FIQ, p<0.05), and auditory verbal learning test (AVLT). In the right temporal lobectomy group (N=16), improvement in PIQ, FIQ, and AVLT reached to statistical significance (p<0.05). In the left temporal lobecto-my group (N=20), improvement in PIQ was significant (p<0.05). In terms of the size of resection, there were tendencies that the cognitive function is more improved in patients with larger hippocampal resection (>2 cm) and in patients with smaller temporal cortical resection (4 cm). CONCLUSIONS: Patients became seizure free after tailored ATLAH may have improvement in performance IQ and full scale IQ. Right side resection, larger hippocampal resection, and smaller lateral temporal resection show better postoperative cognitive function. (J Korean Neurol Assoc 19(2):116~124, 2001)
Adult ; Anterior Temporal Lobectomy* ; Epilepsy ; Epilepsy, Temporal Lobe* ; Follow-Up Studies ; Humans ; Intelligence* ; Memory* ; Seizures ; Temporal Lobe* ; Verbal Learning

This study was performed to observe the effectiveness of thymectomy in the management of myasthenia gravis. Twenty-seven myasthenic patients were undergone thymectomy at Keimyung University Dongsan Hospital between January 1981 and December 1990. The most prevalent age group was the 3rd decade and the myasthenic syrnptom developed below thirty in most. Seven patients had remission and 10 patients fared better after thymectomy. There was no significant effect with age and duration of the disease in the result of thymectomy. Those with less severe group had better response than more severe group and non-thymoma group had higher remission rate without statistical significance than thymoma group. There were better response and more complications in the group with maximal thymectomy than simple thymectomy. This study demonstrated that the effect of thymectomy was better in less severe, nontymoma and maximal thymectomy group in myasthenia gravis.
Humans ; Myasthenia Gravis* ; Thymectomy* ; Thymoma