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Shigeki Kameyama - One of the best experts on this subject based on the ideXlab platform.

  • Asymmetric Gelastic Seizure as a lateralizing sign in patients with hypothalamic hamartoma.
    Epilepsy & behavior : E&B, 2019
    Co-Authors: Shigeki Kameyama, Hiroshi Shirozu, Hiroshi Masuda
    Abstract:

    Abstract Gelastic Seizure (GS) is a cardinal symptom of hypothalamic hamartoma (HH), which is intractable but surgically remediable. Although facial asymmetry with GS has not been extensively discussed, asymmetric GS has been frequently recognized in our large series. We hypothesized that asymmetric GS represents a lateralizing sign caused by the epileptic propagation from the attachment of the HH. To examine this hypothesis, the positive predictive value (PPV) and diagnostic odds ratio (DOR) of asymmetric GS were validated to predict the side of HH attachment. In 103 cases registered to the present analysis, asymmetric GS was recognized in 71 patients and symmetric GS in 32. Asymmetric GS with a lopsided grimace was exclusively observed on the side contralateral to unilateral HH in 39 patients and to the dominant attachment of 23 HHs with bilateral attachment (true positive, n = 62). In contrast, asymmetric GS was exhibited independently on both sides in 4 patients with bilaterally attached HH and on the side ipsilateral to the dominant attachment in the other 4. Symmetric HH attachments were identified in 1 patient (false negative, n = 9). Asymmetric GS was a reliable lateralizing sign with high DOR (6.08) and PPV (78%) to predict the side of epileptic propagation. Furthermore, the present study demonstrated the probability of Seizure propagation from bilateral attachment, and this evidence provides a new rationale to the surgical strategy of bilateral disconnection for HH with bilateral attachment.

  • Ictogenesis and symptomatogenesis of Gelastic Seizures in hypothalamic hamartomas: an ictal SPECT study.
    Epilepsia, 2010
    Co-Authors: Shigeki Kameyama, Hiroshi Masuda, Hiroatsu Murakami
    Abstract:

    Summary Purpose:  To topographically localize the ictogenic zone within hypothalamic hamartomas (HHs) and the symptomatogenic zone for Gelastic Seizure (GS), we analyzed data from both interictal and ictal single photon emission computed tomography (SPECT). Methods:  Ictal SPECT was performed immediately after GS onset in 21 patients with HH (aged 2–36 years, mean 13.8 years) who underwent stereotactic radiofrequency thermocoagulation (SRT). SPECT data were statistically analyzed by means of subtraction ictal SPECT coregistered to magnetic resonance imaging (MRI) (SISCOM) and statistical parametric mapping (SPM). Topographic localization of ictal hyperperfusion areas was evaluated. Results:  SISCOM obtained in 27 studies demonstrated ictal hyperperfusion in the HH interface zone in 16 studies of 13 patients (hot HH group). In these patients, HHs were significantly larger than those without hyperperfusion of HH in 11 studies of 8 patients (21.4 ± 10.3 vs. 12.3 ± 7.3 mm in diameter, p 

  • Stereotactic radiofrequency thermocoagulation for hypothalamic hamartoma with intractable Gelastic Seizures.
    Epilepsy Research, 2007
    Co-Authors: Junpei Homma, Shigeki Kameyama, Hiroshi Masuda, Takehiko Ueno, Ayataka Fujimoto, Makoto Oishi, Masafumi Fukuda
    Abstract:

    Management of hypothalamic hamartoma with intractable Gelastic epilepsy remains controversial. We have used stereotactic thermocoagulation for treatment of hypothalamic hamartoma with intractable Gelastic epilepsy since 1997. Herein, we review our experience in five cases to clarify the usefulness of this treatment. A total of five patients with hypothalamic hamartoma were treated by stereotactic thermocoagulation at our hospital during the period October 1997 through February 2004. In all patients, the hamartoma was less than 10mm in diameter and was located on the floor of the third ventricle with sessile attachment to the wall. To identify ictal onset, chronic intracranial electroencephalography was performed in three patients with the use of a depth electrode implanted in the hamartoma. Attempts were made to induce Gelastic Seizure by electrical stimulation of the hamartoma in three patients. After magnetic resonance imaging-guided targeting, radiofrequency thermocoagulation of the boundary between the hamartoma and normal hypothalamus was performed to achieve disconnection effects. Marked reductions in Seizure frequency were obtained in all cases, with three patients becoming Seizure-free after the procedure. No intraoperative complications occurred except in one patient who experienced acute and transient panidrosis with hot flushes during coagulation. Our results suggest that stereotactic thermocoagulation of hypothalamic hamartoma is an acceptable treatment option for patients with intractable Gelastic Seizures.

Hiroshi Masuda - One of the best experts on this subject based on the ideXlab platform.

  • Asymmetric Gelastic Seizure as a lateralizing sign in patients with hypothalamic hamartoma.
    Epilepsy & behavior : E&B, 2019
    Co-Authors: Shigeki Kameyama, Hiroshi Shirozu, Hiroshi Masuda
    Abstract:

    Abstract Gelastic Seizure (GS) is a cardinal symptom of hypothalamic hamartoma (HH), which is intractable but surgically remediable. Although facial asymmetry with GS has not been extensively discussed, asymmetric GS has been frequently recognized in our large series. We hypothesized that asymmetric GS represents a lateralizing sign caused by the epileptic propagation from the attachment of the HH. To examine this hypothesis, the positive predictive value (PPV) and diagnostic odds ratio (DOR) of asymmetric GS were validated to predict the side of HH attachment. In 103 cases registered to the present analysis, asymmetric GS was recognized in 71 patients and symmetric GS in 32. Asymmetric GS with a lopsided grimace was exclusively observed on the side contralateral to unilateral HH in 39 patients and to the dominant attachment of 23 HHs with bilateral attachment (true positive, n = 62). In contrast, asymmetric GS was exhibited independently on both sides in 4 patients with bilaterally attached HH and on the side ipsilateral to the dominant attachment in the other 4. Symmetric HH attachments were identified in 1 patient (false negative, n = 9). Asymmetric GS was a reliable lateralizing sign with high DOR (6.08) and PPV (78%) to predict the side of epileptic propagation. Furthermore, the present study demonstrated the probability of Seizure propagation from bilateral attachment, and this evidence provides a new rationale to the surgical strategy of bilateral disconnection for HH with bilateral attachment.

  • Ictogenesis and symptomatogenesis of Gelastic Seizures in hypothalamic hamartomas: an ictal SPECT study.
    Epilepsia, 2010
    Co-Authors: Shigeki Kameyama, Hiroshi Masuda, Hiroatsu Murakami
    Abstract:

    Summary Purpose:  To topographically localize the ictogenic zone within hypothalamic hamartomas (HHs) and the symptomatogenic zone for Gelastic Seizure (GS), we analyzed data from both interictal and ictal single photon emission computed tomography (SPECT). Methods:  Ictal SPECT was performed immediately after GS onset in 21 patients with HH (aged 2–36 years, mean 13.8 years) who underwent stereotactic radiofrequency thermocoagulation (SRT). SPECT data were statistically analyzed by means of subtraction ictal SPECT coregistered to magnetic resonance imaging (MRI) (SISCOM) and statistical parametric mapping (SPM). Topographic localization of ictal hyperperfusion areas was evaluated. Results:  SISCOM obtained in 27 studies demonstrated ictal hyperperfusion in the HH interface zone in 16 studies of 13 patients (hot HH group). In these patients, HHs were significantly larger than those without hyperperfusion of HH in 11 studies of 8 patients (21.4 ± 10.3 vs. 12.3 ± 7.3 mm in diameter, p 

  • Stereotactic radiofrequency thermocoagulation for hypothalamic hamartoma with intractable Gelastic Seizures.
    Epilepsy Research, 2007
    Co-Authors: Junpei Homma, Shigeki Kameyama, Hiroshi Masuda, Takehiko Ueno, Ayataka Fujimoto, Makoto Oishi, Masafumi Fukuda
    Abstract:

    Management of hypothalamic hamartoma with intractable Gelastic epilepsy remains controversial. We have used stereotactic thermocoagulation for treatment of hypothalamic hamartoma with intractable Gelastic epilepsy since 1997. Herein, we review our experience in five cases to clarify the usefulness of this treatment. A total of five patients with hypothalamic hamartoma were treated by stereotactic thermocoagulation at our hospital during the period October 1997 through February 2004. In all patients, the hamartoma was less than 10mm in diameter and was located on the floor of the third ventricle with sessile attachment to the wall. To identify ictal onset, chronic intracranial electroencephalography was performed in three patients with the use of a depth electrode implanted in the hamartoma. Attempts were made to induce Gelastic Seizure by electrical stimulation of the hamartoma in three patients. After magnetic resonance imaging-guided targeting, radiofrequency thermocoagulation of the boundary between the hamartoma and normal hypothalamus was performed to achieve disconnection effects. Marked reductions in Seizure frequency were obtained in all cases, with three patients becoming Seizure-free after the procedure. No intraoperative complications occurred except in one patient who experienced acute and transient panidrosis with hot flushes during coagulation. Our results suggest that stereotactic thermocoagulation of hypothalamic hamartoma is an acceptable treatment option for patients with intractable Gelastic Seizures.

Masafumi Fukuda - One of the best experts on this subject based on the ideXlab platform.

  • Stereotactic radiofrequency thermocoagulation for hypothalamic hamartoma with intractable Gelastic Seizures.
    Epilepsy Research, 2007
    Co-Authors: Junpei Homma, Shigeki Kameyama, Hiroshi Masuda, Takehiko Ueno, Ayataka Fujimoto, Makoto Oishi, Masafumi Fukuda
    Abstract:

    Management of hypothalamic hamartoma with intractable Gelastic epilepsy remains controversial. We have used stereotactic thermocoagulation for treatment of hypothalamic hamartoma with intractable Gelastic epilepsy since 1997. Herein, we review our experience in five cases to clarify the usefulness of this treatment. A total of five patients with hypothalamic hamartoma were treated by stereotactic thermocoagulation at our hospital during the period October 1997 through February 2004. In all patients, the hamartoma was less than 10mm in diameter and was located on the floor of the third ventricle with sessile attachment to the wall. To identify ictal onset, chronic intracranial electroencephalography was performed in three patients with the use of a depth electrode implanted in the hamartoma. Attempts were made to induce Gelastic Seizure by electrical stimulation of the hamartoma in three patients. After magnetic resonance imaging-guided targeting, radiofrequency thermocoagulation of the boundary between the hamartoma and normal hypothalamus was performed to achieve disconnection effects. Marked reductions in Seizure frequency were obtained in all cases, with three patients becoming Seizure-free after the procedure. No intraoperative complications occurred except in one patient who experienced acute and transient panidrosis with hot flushes during coagulation. Our results suggest that stereotactic thermocoagulation of hypothalamic hamartoma is an acceptable treatment option for patients with intractable Gelastic Seizures.

Yoshio Nakajima - One of the best experts on this subject based on the ideXlab platform.

  • Different patterns of dipole source localization in Gelastic Seizure with or without a sense of mirth.
    Neuroscience research, 2002
    Co-Authors: Hiroto Iwasa, Tadahiko Shibata, Seiichiro Mine, Keijirou Koseki, Kimiko Yasuda, Yasufumi Kasagi, Motohiro Okada, Hirooki Yabe, Sunao Kaneko, Yoshio Nakajima
    Abstract:

    Dipole source localization corresponding to interictal spikes were estimated using EEG dipole tracing with a realistic three-shell head model in three patients with cryptogenic Gelastic epilepsy. The dipole sources in two patients, whose Gelastic Seizures were accompanied by a subjective feeling of mirth, were estimated in the right or left medio-basal temporal regions. In the other patient, with Gelastic Seizures without a sense of mirth, the dipole sources were localized in the right frontal region corresponding to the anterior cingulate. The results suggest that the neural activities in hippocampal regions are involved with the generation of Gelastic Seizures with a sense of mirth and those in the cingulate might be associated with the motor act of laughter.

Hiroto Iwasa - One of the best experts on this subject based on the ideXlab platform.

  • Different patterns of dipole source localization in Gelastic Seizure with or without a sense of mirth.
    Neuroscience research, 2002
    Co-Authors: Hiroto Iwasa, Tadahiko Shibata, Seiichiro Mine, Keijirou Koseki, Kimiko Yasuda, Yasufumi Kasagi, Motohiro Okada, Hirooki Yabe, Sunao Kaneko, Yoshio Nakajima
    Abstract:

    Dipole source localization corresponding to interictal spikes were estimated using EEG dipole tracing with a realistic three-shell head model in three patients with cryptogenic Gelastic epilepsy. The dipole sources in two patients, whose Gelastic Seizures were accompanied by a subjective feeling of mirth, were estimated in the right or left medio-basal temporal regions. In the other patient, with Gelastic Seizures without a sense of mirth, the dipole sources were localized in the right frontal region corresponding to the anterior cingulate. The results suggest that the neural activities in hippocampal regions are involved with the generation of Gelastic Seizures with a sense of mirth and those in the cingulate might be associated with the motor act of laughter.

  • a study on neurophysiological mechanism of the Gelastic Seizure estimations of electrical source generators by means of the dipole tracing
    Journal of The Japan Epilepsy Society, 1994
    Co-Authors: Keijiro Koseki, Hiroto Iwasa, Tadahiko Shibata, Toshihiko Ito, Toshio Sato
    Abstract:

    てんかん性笑い発作の発現機序を検討する目的で, 笑い発作のみを発作症状とする1例に, 双極子追跡法 (Dipole Tracing: DT) および123I-IMP SPECTを施行した。この症例の発作間欠期脳波は, 発作の初発から間もない時期では, 右前側頭部優位の棘徐波結合であったが, 後期においては多棘徐波結合が頻発するようになった。これらの突発波のDT分析を行った結果, 早期の棘波では右側頭葉内側部に等価電流双極子 (equivalent current dipole: ECD) が推定され, 後期の多棘波の先行棘波成分は早期の棘波と同様に右側頭葉内側部に, 後発棘波成分は前頭葉内側部にそれぞれECDが推定された。また, 同時期の123I-IMP SPECTでは, 右前側頭葉および前頭葉内側部に血流増加が認められた。これらの結果は, 笑い発作の発現には側頭葉内側部のみならず隣接の大脳辺縁系が関与していることを示唆している。