Clinically localized seizure focus maybe not exactly the position of abating seizures: a computational evidence

Fluency tests are frequently used in clinical practice to asses executive functions. The literature data are not unequivocal although in a great number of papers is pointed out the importance of the left hemisphere, specially of the left frontal lobes in the mediation of phonological fluency and the right hemisphere in the mediation of nonverbal fluency. This paper considers the suitability of fluency tests for the detection of left versus right seizure laterality. The sample consisted of thirty-two epilepsy patients divided into two groups: LHF-participants with the seizure focus in the left hemisphere (n=16), and DHF-participants with the seizure focus in the right hemisphere (n=16), and K-the control group of t age-matched healthy children (n=50) aged 7-11 years. The qualitative and quantitative comparison of the phonological and nonverbal fluency performance was carried out in consideration of the seizure laterality as well as compared to the healthy controls. The results of phonological fluency performance revealed that the performance of the LHF group was significantly reduced as compared to both DHF and K group. The analysis of nonverbal fluency performance revealed that the performance of the DHF group was significantly reduced as compared to both LHF and K group The qualitative analysis obtained valuable data, which could additionally contribute to the neuropsychological evaluation of the left versus right seizure laterality.

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Post-ictal recognition memory predicts laterality of temporal lobe seizure focus: Comparison with post-operative data

Neuropsychologia ◽

10.1016/0028-3932(90)90111-z ◽

1990 ◽

Vol 28 (9) ◽

pp. 957-967 ◽

Cited By ~ 31

Author(s):

D.G. Andrewes ◽

A. Puce ◽

P.F. Bladin

Keyword(s):

Recognition Memory ◽

Temporal Lobe ◽

Seizure Focus ◽

Operative Data ◽

Temporal Lobe Seizure

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Stimulation of the Hippocampus and the Seizure Focus

Textbook of Stereotactic and Functional Neurosurgery ◽

10.1007/978-3-540-69960-6_169 ◽

2009 ◽

pp. 2839-2852

Author(s):

A. L. Velasco ◽

F. Velasco ◽

M. Velasco ◽

G. Castro ◽

J. D. Carrillo-Ruiz ◽

...

Keyword(s):

Seizure Focus ◽

Stimulation Of

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How to Inject Ictal SPECT? From Manual to Automated Injection

10.21203/rs.3.rs-255385/v1 ◽

2021 ◽

Author(s):

Xavier Setoain ◽

Francisco Campos ◽

Antonio Donaire ◽

Maria Mayoral ◽

Andres Perissinotti ◽

...

Keyword(s):

Injection System ◽

Control Group ◽

Epileptogenic Zone ◽

Drug Resistant ◽

Injection Time ◽

Tracer Injection ◽

Ictal Spect ◽

Seizure Focus ◽

Drug Resistant Epilepsy ◽

Automated Injection

Abstract BackgroundSuccessful surgery depends on the accurate localization of epileptogenic zone before surgery. Ictal SPECT is the only imaging modality that allows identification of the ictal onset zone by measuring the regional cerebral blood flow at the time of injection. The main limitations of ictal SPECT in epilepsy are the complex methodology of the tracer injection during a seizure. To overcome these limitations, we present the main features of the first automated injector for ictal SPECT (epijet, LemerPax; La Chapelle -sur-Erdre; France). In this study we compared traditional manual injection with automated injection for ictal SPECT in122 patients with drug-resistant epilepsy. MethodsThe study included 55 consecutive prospective patients with drug-resistant epilepsy undergoing injection with the automated injector. The control group was our retrospective database of a historic pool of 67 patients, injected manually from 2014-2016. Calculated annual exposure/radioactive dose for operators was measured. Injection time, seizure focus localization with ictal SPECT, as well as repeated hospitalizations related to fails injections were compared in these two groups of patients. ResultsThere were no differences in the average injection time with epijet (13 s) compared with the traditional manual injection (14s). The seizure focus was successfully localized with ictal SPECT with epijet in 44/55 (80%) patients and with manual injection in 46/67 (68%) patients (p=0.694). Repeated studies were required in 16/67 (23%) patients in the manual injection group compared to 4 patients (7%) in the epijet group (p=0.022). Calculated annual exposure/dose for operators of 0.39 mSv/year and administered dose error inferior to 5% are other advantages of epijet. ConclusionThe first results using epijet are promising in adjustment of the injection dose, reducing the rate of radiation exposure for patients and nurses, maintaining the same injection time and allowing high SPECT accuracy. These preliminary results support the use of an automated injection system to inject radioactive ictal SPECT doses in epilepsy units.

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Epilepsy Surgery Evaluation

Clinical Neurophysiology ◽

10.1093/med/9780190259631.003.0013 ◽

2016 ◽

pp. 196-208

Author(s):

Joseph F. Drazkowski

Keyword(s):

Surgical Resection ◽

Surgical Approach ◽

Medical Management ◽

Gold Standard ◽

Evaluation Process ◽

Precise Localization ◽

Intracranial Eeg ◽

Seizure Focus ◽

Surgical Evaluation ◽

Medically Refractory Epilepsy

Epilepsy can be a devastating illness for those afflicted. Unfortunately, approximately one-third of people diagnosed with epilepsy are not effectively treated with standard medical management. People with medically refractory epilepsy can be treated and possibly cured of their disease utilizing a surgical approach. The electroencephalogram currently remains the “gold standard” for characterizing and localizing the ictal onset zone. Standard surface and sometimes intracranial EEG, when appropriate, are typically utilized in the evaluation process. The epilepsy surgical evaluation is sometimes enhanced with the utilization of SPECT/SISCOM imaging to further help confirm the seizure focus. Data gathered during the evaluation process guide the surgical resection, with improved remission rates correlating with precise localization of the ictal onset zone. This chapter describes the current presurgical epilepsy evaluation using the EEG and SPECT scanning.

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