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T Mihara

Publications and source records attributed to T Mihara.

At least 55 records · Page 3Linked to original sources
PubMed1992

Conditions for omitting invasive long-term monitoring before surgical resection in patients with temporal lobe epilepsy.

The omission of invasive long-term monitoring before surgical resection in patients with epilepsy should be permitted only for those in whom the epileptogenic focus is presumed to localize unilaterally in the mesial aspect of the temporal lobe. The localization may well be confirmed through noninvasive measures. Retrospective analyses of data obtained from noninvasive investigations (scalp-recorded and sphenoidal EEGs, neuroimages, and electroclinical seizure manifestations) were carried out in 58 patients. The localization of their epileptogenic focus was subsequently confirmed by the implantation of both intracerebral and subdural electrodes; the focus had an amygdalohippocampal origin in 41 patients and a lateral temporal origin in 17 patients. From the comparison of noninvasive findings between these two groups, we propose the following indispensable conditions for omitting an invasive evaluation: 1. Appearance of focal epileptic discharges unilaterally in the sphenoidal lead observed during the simple phase of partial seizures, or unilateral discharges with predominancy in the sphenoidal lead during the early phase of complex partial seizures. 2. Interictal spikes on scalp-recorded EEGs localizing unilaterally in the anterior region of the temporal lobe, and if bilaterally independent, presenting with unilateral predominancy in a ratio of greater than 4:1. 3. Presence of autonomic signs in the initial phase of signal symptoms. 4. Neuroimaging findings in the mesial temporal region: elongated T2 on MRI and hippocampal atrophy, or a tumorous lesion. The lateralization conforms to interictal and ictal paroxysmal EEG findings. There were 8 patients with seizure of amygdalohippocampal origin who satisfied all the indispensable condition, but not a single patient with seizures of lateral temporal origin.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Neuropsychological evaluation before and after surgical treatment of temporal lobe epilepsy.

We present the results of pre- and postoperative neuropsychological evaluations of 58 patients with temporal lobe epilepsy who underwent a chronic intracranial EEG monitoring and a subsequent standard anterior temporal lobectomy. Wada's test provided valuable information on the speech dominant side and on the focus localization. Some warning signs as well as verbal automatisms indicated the effect for focus localization and lateralization. The results of interictal neuropsychological tests suggested that each subgroup of TLE performed differently. A postoperative neuropsychological performance has improved in many tests that may be explained by the diminished epileptic bombardment resulting from the resection.

Adolescent↗
PubMed1991

[Treatment of seventy-eight patients with testicular tumors].

Seventy-eight patients with testicular tumors were treated in our clinic between April, 1972 and October, 1990. The average age of patients with seminoma (37.5 yrs) was higher than that (24.5 yrs) of those with non-seminomatous germ cell tumor (NSGCT). Histopathologically, 34 patients had seminoma and 36 patients had NSGCT. The remaining 8 patients had non-germinal cell tumors. The 5-year survival rate was 76.7%, 90.3% and 75.8% for all patients, seminoma group and NSGCT group, respectively. As for seminoma group, the 5-year survival rate was 100%, 50.0% and 33.3% for Stage I, Stage IIb and Stage III, respectively. The survival rate of Stage IIb and Stage III in seminoma group were lower than Stage I statistically. In NSGCT group, the 5-year survival rate was 100% for Stage I and 26.7% for Stage III, between the two groups there was significant difference. The higher serum LDH and HCG levels, the lower the survival rate in NSGCT. Serum AFP, beta-HCG levels and ESR were unrelated to the survival rate. The survival rate for the patients treated by the chemotherapy including CDDP was compared to those treated by the other therapy in germ cell tumor (greater than or equal to Stage IIb). The survival rate of CDDP group was higher than the others (p less than 0.01).

Adult↗
PubMed1990

Surgical treatment of epilepsy in the comprehensive care program: advantages and considerations.

To properly establish the surgical treatment of epilepsy in the comprehensive care program, we planned a surgical strategy mainly for a temporal lobe epilepsy and have performed 60 temporal lobectomies. The surgical candidates were selected from 142 patients who met the initial criteria, and passed the initial evaluation for surgical intervention. Forty-five patients had long-term intracranial EEG recording, and circumscribed organic lesions were disclosed in 27 patients by neuroimaging techniques. The outcome of 23 patients who were followed for 2 years postoperatively was complete freedom from complex partial seizures in 17 patients (74%) and an increase in full employment from 2 to 10 patients. Despite the possible surgical complications, including detrimental effects on the higher cerebral functions, it is essential that the surgical treatment of epilepsy should be established as a part of the comprehensive care program. Our experiences and analyses of the state of the art in surgical intervention also suggest that surgical indications for more intractable patients whose social adjustment is less hopeful should be established and the surgical care system for these patients should also be planned. Furthermore, some patients may be free from recurrent seizures postoperatively, but still have difficulties in social rehabilitation. The problems for such patients remain unsolved.

Adult↗
PubMed1990

Subtypes of temporal lobe epilepsies: a clinical point of view.

We studied 40 patients with temporal lobe epilepsies who had long-term intracranial EEG recordings and temporal lobectomies. They were divided into 3 groups on the basis of the anatomical site of seizure origin. An electrode implantation technique combined intracerebral depth electrodes with subdural strip electrodes. The seizures were of amygdalo-hippocampal origin in 18 patients, lateral temporal in 13 patients, and temporo-basal in 9 patients. The clinical and EEG features were reviewed retrospectively with regard to 3 factors in each patient: localization of interictal spikes in the scalp-recorded EEG, signal symptoms (auras), and presumed etiologies. Epilepsy with amygdalo-hippocampal and lateral temporal seizures was found to be distinguishable by the electroclinical features. It seems practical to classify these 2 subtypes of temporal lobe epilepsies as in the 1989 Classification of Epilepsies and Epileptic Syndromes. Temporal lobe epilepsies thus defined can be regarded as epileptic syndromes rather than a cluster of seizure manifestations.

Adolescent↗
PubMed1990

[Effects of unilateral temporal lobectomy on verbal dichotic listening test].

Verbal dichotic listening test was conducted before and after anterior temporal lobectomy on 25 patients who underwent the operation because of their medication-resistant epileptic seizures. Their speech dominance by Wada test was all left sided. 1. Preoperatively, patients having the epileptogenic focus in the right temporal lobe (R-TLE) and those having the focus in the left (L-TLE) were, as expected, all right-ear dominant. The mean number of correct responses was fewer in L-TLE than in R-TLE group. 2. Postoperatively, no detrimental effects for recognition of verbal auditory stimuli by the ear contralateral to the focus was observed both in L-TLE and in R-TLE group. 3. Postoperatively, the ear-dominance shifted: to the left in patients with L-TLE, and to the right more conspicuously in patients with R-TLE compared to the preoperative scores. In other words, the recognition ability by the ears ipsilateral to the side of focus, or of resected temporal lobe, was ameliorated. Summarizing, the unilateral anterior temporal lobectomy did not cause "lesion effect" but yielded improvement of verbal auditory recognition by ears ipsilateral to the epileptogenic focus. Diminished epileptic bombardment resulted in by the resection surgery may be a possible explanation.

Adult↗
PubMed1990

Feasibility of subclassification of temporal lobe epilepsy (1989): an etiological overview.

Temporal lobe epilepsy with amygdalohippocampal seizures may have episodes of severe convulsions in childhood more frequently and the onset age is significantly lower compared to epilepsy with lateral temporal seizures. To the contrary, tumorous lesions are found more frequently in epilepsy with lateral temporal seizures. In view of the presumed known etiologies in relation to the localization of epileptogenic foci, the Classification of Epileptic Syndrome (1989), subdividing temporal lobe epilepsies into 2 groups, was found to be useful.

Adult↗
PubMed1989

Focal CT abnormality and epileptogenic focus.

In 31 patients with temporal lobe epilepsy, the precise site of epileptogenic focus was determined by means of a depth EEG recording as one of the presurgical evaluations. In 13 patients, a CT scan revealed focal lesions; 7 in the left temporal lobe and 6 in the right temporal lobe. In 5 of the 7 patients and in 5 of the 6 patients the epileptogenic foci were determined in the temporal lobe on the side of a CT lesion. However, in 2 of the patients with a CT lesion in the left temporal lobe, independent epileptogenic foci were found in both the temporal lobes, and in the other patient with a CT lesion in the right temporal lobe, they were found in the right frontal and left temporal lobes. Thus, the CT lesions agreed in lateralization and focality with the epileptogenic foci in 10 of the 13 patients (77%), but they disagreed in 3 (23%). A CT lesion disclosed in the temporal lobe does not necessarily indicate the side and/or site where the epileptogenic focus may be localized. Although exceptions may be made, spatial disagreement was exemplified between the CT lesion and epileptogenic focus. Therefore, extreme caution has to be taken on the side and/or site of the epileptogenic focus when functional surgical indication is to be made.

Adolescent↗
PubMed1989

MRI lesion and epileptogenic focus in temporal lobe epilepsy.

The spatial relationship between a circumscribed lesion in the temporal lobe detected by MRI and an epileptogenic focus identified by ictal depth EEG along with a correlation of the MRI lesion with neuropathological findings were investigated in patients with medically intractable temporal lobe epilepsy but without any focal lesion on CT. Four parameters (an areal ratio of the temporal lobe against the hemisphere, area and calculated T1, T2 values of the hippocampus) were used to determine the abnormal MRI side. An agreement was reached in 67-72% of 18 patients between the abnormal values of the hippocampal area and of calculated T1, T2 and the side of the epileptogenic focus. In 14 of 17 patients, typical hippocampal sclerosis was demonstrated in resected tissue in accordance with the MRI lesions (atrophy and/or prolonged T2 of hippocampus). These results imply: 1) MRI abnormality thus defined may, if not all, indicate the side of the epileptogenic focus, and 2) also the presence of hippocampal sclerosis. It was emphasized that the MRI lesion would be a usable instrument to explore the causal relationship of hippocampal sclerosis to a generation of epileptogenic lesions as well as for presurgical evaluation.

Adolescent↗
PubMed1989

Emotional facial expressions at the onset of temporal lobe seizures: observations on scalp and intracranial EEG recordings.

The initial facial expressions of 195 complex partial seizures of 98 patients with temporal lobe epilepsy were reviewed in relation to the laterality and focality of electroencephalographic (EEG) seizure origin. A neutral expression was observed most often (71) followed in frequency by expressions of disgust (13), happiness (7) and sadness (7). There was no expression of anger, surprise and fear. No correlation was found between the type of facial expression and the side of seizure origin. However, among 27 patients examined by means of intracranial EEG recordings, it was evident that a disgust expression occurred with oro-alimentary automatisms at the beginning of mesial temporal lobe seizures, whereas a happy one occurred without oro-alimentary automatisms at the beginning of lateral temporal lobe seizures. Although the facial expressions were not always related to the concurrent ictal emotion, it appeared that the majority of the patients with the disgust expression had autonomic features, while those of the happy/sad expression had psychic/sensory ones. It was concluded that (1) a disgust expression occurs as an indirect consequence of "crude sensation," while a happy/sad expression occurs as a direct consequence of "elaborate mental state" (Jackson) and (2) facial expressions must be reviewed in relation to focality rather than laterality in temporal lobe seizures.

Adolescent↗
PubMed1989

A correlative study between hippocampal atrophy quantified by tomo-pneumoencephalography and epileptogenic focus in temporal lobe epilepsy.

It appeared certain that we can quantify the rate of hippocampal atrophy by utilizing the sagittal cuts in tomo-pneumoencephalography. This is a reliable method to infer the side of the epileptogenic focus in temporal lobe epilepsy since a close correlation was disclosed between the side with more atrophic features of the hippocampus and that of the epileptogenic focus explored by depth EEG, in particular, in the mesial temporal focus group. On the other hand, it seems to be plausible that the hippocampal atrophy could be secondarily induced by epileptic discharges in the lateral temporal group. Namely, controversies dealing with the casual relationship of hippocampal atrophy should be discussed based on the epileptogenic focus localization in temporal lobe epilepsy.

Amygdala↗