BACKGROUND: The Wada test is an essential part of the preoperative evaluations in candidates for epilepsy surgery. Impaired reactions (IR) to intracarotid sodium amytal infusions include: confusion, disorientation, and decreased respon-siveness, thereby confounding test results. We retrospectively analyzed the factors affecting the impaired reactions (IR) regarding both individual and methodologic factors. METHODS: Subjects included 202 patients (age;28.5+/-9.48, range:8 to 64 years, M:F=113:89) with intractable epilepsy. Patients with IR (IR group) and those without IR (Non-IR group) were compared with respect to individual factors such as: age, sex, epilepsy syndromes, injected hemispheres, dominan-cy as well as methodologic factors including amobarbital doses. With regards to the dose of amobarbital, the total accu-mulated dose as well as the initial injected dose, were used. RESULTS: IR was observed in 50 patients (24.7%). Compared to the non-IR group, the IR group had more prolonged, contralateral weakness and total test times, but the same duration of EEG changes. IR occurred more frequently with injections into the left hemisphere (p<0.001), the dominant hemi-sphere (p<0.0001), and contralateral hemisphere of epileptic focus (p<0.07). The IR group received significantly higher amounts of amobarbital than the non-IR group (p<0.05). Considering the oversedation as well as the undersedation of amobarbital together, 100mg of amobarbital was the most appropriate dose in the Wada test. CONCLUSIONS: These results suggest that dominant hemisphere injections and usage of higher doses of amobarbital can frequently produce IR in the Wada test. The ideal dose of amobarbital in the Wada test for Korean patients should be 100mg.
Amobarbital ; Electroencephalography ; Epilepsy ; Humans ; Retrospective Studies

BACKGROUND: We studied the accuracy, lateralization criteria of Wada test in patients with temporal lobe epilepsy(TLE). We also evaluated material specific memory and determined the stimulus which can classify best between right and left TLE among four different types of stimuli. METHODS: We examined Wada memory performance in 33 patients(15 left, 18 right) with TLE who underwent surgery and who were good seizure outcome at least 1 year follow-up. Twelve stimuli consited of figures, written words, geometric designs and real objects were presented after Amytal injection. The recognition memory test was performed at 10 minutes after the injection and hemisphere memory performance of each stimulus and total stimuli were obtained by(number of stimuli recognized / number of stimuli presented x 100%). Classification rate, best stimulus for lateralization, and suitable lateralization criteria were determined by discriminant analysis and Chi-square test. Hemispheric memory difference of each stimulus was analyzed by paired-sample Student's t-test in left temporal lobectomy(LTL) and right temporal lobectomy(RTL) groups. RESULTS: No significant difference was observed in pre-Wada memory score and in IQ between LTL and RTL group. The classification rate of Wada test in terms of lateralization by discriminant analysis was 81.82%. The accuracy was 75.8% at 10% and 15% lateralization criteria and was 63.6% and 45.5% at 20% and 25% lateraliza.
Amobarbital ; Classification ; Follow-Up Studies ; Humans ; Memory* ; Seizures ; Temporal Lobe

BACKGROUNDS: To examine the effects of seizure laterality and stimulus type on Wada memory performance in patients with temporal lobe epilepsy(TLE). METHODS: The subjects were 43 patients with medically intractable TLE (left TLE 26, Right TLE 17) who had no or rare seizures after surgery. The memory stimuli were concrete figures for some subjects and abstract figures for the other subjects. RESULTS: A clinical criterion of at least 2-points difference between left and right injections correctly classified 31(72%) patients into left and right TLE groups, with 4(9%) patients falsely classified. A discriminant function analysis(DFA) based on left and right injection scores allowed for a correct classification of 37(86%) patients into left and right TLE groups. When the memory stimuli were concrete figures, the correct classification rate was greater for right than left TLE patients. In contrast, with abstract figures, the correct classification rate was greater for left than right TLE patients. CONCLUSIONS: The Wada memory test is a valuable diagnostic aid in lateralizing temporal epileptogenic foci. Stimulus type as well as seizure lateralization is a major determinant of Wada memory asymmetries.
Amobarbital* ; Classification ; Epilepsy, Temporal Lobe ; Humans ; Memory* ; Seizures ; Temporal Lobe*

Drug-assisted interviews are useful for psychiatric diagnosis and treatment. However, amobarbital, a typical medication used for this purpose, is associated with elevated risk of respiratory depression. Benzodiazepines are good substitutes for amobarbital, with similar therapeutic effects and fewer complications. Although drug-assisted interviews are not widely used, they may be beneficial for selected patients who do not respond to conventional treatments such as supportive psychotherapy or psychopharmacotherapy. We report two cases of dissociative amnesia that were treated using lorazepam-assisted interviews. The use of lorazepam in drug-assisted interviews is effective and safe for resolving dissociative amnesia.
Amnesia ; Amobarbital ; Benzodiazepines ; Humans ; Lorazepam ; Mental Disorders ; Psychotherapy ; Respiratory Insufficiency

BACKGROUND: The interpretation of Wada memory test is various in different epilepsy centers. Four types of Wada memory score (WMS) were defined by four different criteria to determine the best WMS in predicting postsurgical memory outcome. METHODS: Twenty temporal lobe epilepsy patients underwent Wada test before surgery and pre- and post-operative neuropsychological tests. WMS was obtained by four ways; including 1) total stimulating items, 2) items presented between one and two minutes after amobarbital injection, 3) items presented before ipsilateral EEG slowing decreased to 50%, 4) items presented until EEG slowing disappeared. Wada memory asymmetry index (WAI) was determined by [(WMS of normal side ? WMS of epileptic side)/their mean]. Logical and visual memory tests were performed before and after operation. Neuropsychological asymmetry index (NPAI) was defined as [(postsurgical score ? Presurgical score)/their mean]. Spearman correlation coefficients were obtained between WAIs and NPAIs. RESULTS: WAIs obtained by method 2) and 3) showed relatively good correlation with NPAIs. Visual memory outcome was correlated with WMS better than logical memory both in non-dominant and dominant hemisphere epilepsy groups. The lateralizing value of memory dominance in non-dominant hemisphere epilepsy group was greater than that of dominant group. CONCLUSIONS: Early presented stimuli during Wada test had a better predictive value of postoperative memory outcome.
Amobarbital ; Electroencephalography ; Epilepsy ; Epilepsy, Temporal Lobe ; Humans ; Logic ; Memory* ; Neuropsychological Tests

BACKGROUND AND OBJECTIVES: Interhemispheric memory asymmetry & language 'shift' (right hemisphere restitution of originally left hemisphere functions or vice versa) and its lateralizing value in temporal lobe epilepsy (TLE) have been repeatedly reported. We analyzed the factors influencing the memory asymmetry & language 'shift', which, to our knowledge, has rarely been reported. METHODS: The IAP (Intracarotid Amobarbital Procedure) was performed in 94 patients, who were candidates for temporal lobectomy. We determined language dominance (LD) hemisphere and calculated 'memory asymmetry indexes' (difference of percentage of memory recall between left and right hemisphere). We reviewed sex, history of 'risk factors' (episodes of febrile convulsion, head trauma, or meningoencephalitis during period of infant and early childhood), age of epilepsy-onset, duration of epilepsy, and then correlated each of them with the presence of language shift and the degree of memory asymmetry. RESULTS: Atypical LD (bilateral or right hemisphere LD) was significantly more frequent in left TLE group than in right (left TLE: 19%, right: 0%, p=0.009). The 'shift' of LD hemisphere was more frequent in patients with 'risk factors' (p=0.04). The 'shift' of LD hemisphere was seen only in patients with duration of epilepsy of > 10 years, but statistically not significant(p=0.07). Interhemispheric memory asymmetry occurred in most patients. The presence of 'risk factors' (p=0.05), duration of epilepsy of 10-20 years (p=0.04), and female sex (p=0.01) were significantly associated with the memory asymmetry in left TLE group. But in right TLE group, the memory asymmetry was not associated with above factors. CONCLUSION: Only in left TLE group, the presence of 'risk factors' and duration of epilepsy influenced both interhemispheric memory asymmetry & language 'shift', whereas sex influenced memory asymmetry only. In right TLE, we failed to find correlation. These results could be explained that in right TLE, memory might be easily or rapidly shifted to the contralateral hemisphere, even in absence of above factors.
Amobarbital ; Craniocerebral Trauma ; Epilepsy ; Epilepsy, Temporal Lobe* ; Female ; Humans ; Infant ; Memory* ; Meningoencephalitis ; Seizures, Febrile ; Temporal Lobe*

Backgroud : To examine the predictability of regional cerebral glucose metabolism in determining Wada memory dominance and lateralizing epileptic focus. METHODS: 1 8 F-fluorodeoxyglucose positron emission tomography (FDG-PET) and Wada test were performed in 18 patients with temporal lobe epilepsy (TLE). Regions of interest were determined in mesial, polar, anterior-lateral, mid-lateral, and posterior-lateral regions of the temporal lobe. The asymmetry indices of FDG-PET (PET-AI) were calculated in each ROI of temporal lobe, and those of Wada memory test (Wada-AI) were obtained as well. RESULTS: Pearson correlation coefficient showed Wada-AI was significantly correlated with PET-AI in mesial (r=0.67, p=0.001), polar (r=0.55, p=0.010), anterior-lateral (0.55, p=0.009) and mid-lateral (r=0.51, p=0.016) temporal regions. However, after simple linear regression analysis, PET-AI of mesial temporal region alone was significantly correlated with Wada-AI (p=0.008). In localizing epileptic focus, Wada-AI could correctly lateralize the seizure focus in 90% of the left TLE and 75% of the right TLE patients. No false lateralization by Wada-AI was observed except two patients showing prolonged confusion after amobarbital injection who were not included in this study. The PET-AI of the mesial temporal region showed the highest sensitivity of seizure lateralization (100% of left TLE and 87.5% of right RLE). CONCLUSIONS: Although FDG-PET hypometabolism is observed both at mesial and lateral regions of the temporal lobe in mesial TLE, mesial temporal region appeared to be a dominant and leading area for lateralizing Wada memory dominance and epileptic focus.
Amobarbital ; Epilepsy, Temporal Lobe* ; Glucose ; Humans ; Linear Models ; Memory* ; Metabolism ; Positron-Emission Tomography ; Seizures ; Temporal Lobe*

Is superselective embolization of the brain AVMs, the possibilities of adjacent normal brain tissue damage necessitates preembolic evaluation. The authors performed the Sodium Amytal test on 15 patients with brain AVMs. In the AVM patients with negative Amytal test(30 cases), all patients showed normal pattern on EEG and neurologic examinations after embolization Among the five patients with positive Amytal test, three cases showed neurologic deficit and the others two didn't. In eleven patients. Repeated embolization without the Amytal test were done. Among them, 5 cases showed neurlogic deficit and the others were quite normal. In conclusion, the Amytal test is a useful method of evaluation of the risk to damage normal brain tissue which are supplied by superselected feeding vessels. Combining the EEG with this test is a sensitive and objective method in evaluating patients following the Amytal test. And it is essential to performed the Amytal test for repeat embolization procedures.
Amobarbital* ; Arteriovenous Malformations* ; Brain* ; Electroencephalography ; Humans ; Methods ; Neurologic Examination ; Neurologic Manifestations

The Wada test was performed for lateralization of language and memory function, using intracarotid injection of Sodium Amytal. But, the internal carotid artery(ICA) Wada test has some limitations for testing memory function. The posterior cerebral artery(PCA) Wade test has been designed to modify to modify the ICA Wada test for testing memory function selectively. In our study, 10 patients out of 12 patients with intractable seizure underwent only the ICA Wada test and the other 2 patients underwent both are ICA and the selective PCA Wada test In all 12 patients undergoing the ICA Wada test, we succesfully localized speech and language dominace. Four of 12 patients who underwent the ICA Wada test for evaluation of memory function displayed superior memory functions in one hemisphere, but the other hemisphere also significantly contributed to memory. The selective PCA Wada test, performed in 2 patients, showed successful results of memory function test in both patients. Four of 12 patients underwent temporal lobectomy and there was no major post-operative language or memory deficits. We conclude that the ICA and PCA Wada tests are useful for preoperative evaluation of medically intractable epilepsy, and the PCA Wada test is valuable in memory evaluation in some patients who have hight risk of postoperative global amnesia after temporal lobectomy following equivocal results of memory function by the ICA Wada test.
Amnesia ; Amobarbital ; Drug Resistant Epilepsy* ; Humans ; Memory Disorders ; Memory* ; Passive Cutaneous Anaphylaxis ; Seizures

Wada test has been used as the presurgical evaluation method of memory function in epileptic patient. We report experiences with selective posterior cerebral artery sodium amytal test in two intractable temporal lobe epilepsy patients who showed poor performance in conventional Wada test for the presurgical evaluation. Our procedure consisted of injection of sodium amytal via a microcatheter into the P1 distal segment of the posterior cerebral artery and verbal and visual memory test before and after the injection. We also performed Tc-99m ECD SPECT during the procedure. In one patient showed good memory function during the procedure so operation was performed. But the other patient showed poor memory function so we discharged him without operation.
Amobarbital* ; Epilepsy, Temporal Lobe* ; Humans ; Memory ; Posterior Cerebral Artery* ; Sodium* ; Temporal Lobe* ; Tomography, Emission-Computed, Single-Photon