A new method for intraoperative localization of epilepsy focus by means of a gamma probe

Filho, Omar Carneiro; Filho, Osvaldo Vilela; Ragazzo, Paulo C.; Fonseca, Léa Mirian Barbosa da

doi:10.1590/s0100-39842014000100010

Cited by 2 publications

(1 citation statement)

References 8 publications

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“…The gold standard in seizure focus localization is intracranial implantation of an electrode, such as electrocorticography (ECoG) or stereoelectroencephalography (SEEG). Among them, ECoG detects the electrical signals on the surface of the brain to identify the lesion locations [ 3 – 5 ]. Because the resolution of ECoG is only 10 mm, removing some areas during surgery is often accompanied by excessive excision leading to surgical failure.…”

Section: Introductionmentioning

confidence: 99%

Multimodal Detection for Cryptogenic Epileptic Seizures Based on Combined Micro Sensors

Shen

Jiao

et al. 2020

BioMed Research International

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The cryptogenic epilepsy of the neocortex is a disease in which the seizure is accompanied by intense cerebral nerve electrical activities but the lesions are not observed. It is difficult to locate disease foci. Electrocorticography (ECoG) is one of the gold standards in seizure focus localization. This method detects electrical signals, and its limitations are inadequate resolution which is only 10 mm and lack of depth information. In order to solve these problems, our new method with implantable micro ultrasound transducer (MUT) and photoplethysmogram (PPG) device detects blood changes to achieve higher resolution and provide depth information. The basis of this method is the neurovascular coupling mechanism, which shows that intense neural activity leads to sufficient cerebral blood volume (CBV). The neurovascular coupling mechanism established the relationship between epileptic electrical signals and CBV. The existence of mechanism enables us to apply our new methods on the basis of ECoG. Phantom experiments and in vivo experiments were designed to verify the proposed method. The first phantom experiments designed a phantom with two channels at different depths, and the MUT was used to detect the depth where the blood concentration changed. The results showed that the MUT detected the blood concentration change at the depth of 12 mm, which is the position of the second channel. In the second phantom experiments where a PPG device and MUT were used to monitor the change of blood concentration in a thick tube, the results showed that the trend of superficial blood concentration change provided by the PPG device is the same as that provided by the MUT within the depth of 2.5 mm. Finally, in the verification of in vivo experiments, the blood concentration changes on the surface recorded by the PPG device and the changes at a certain depth recorded by the MUT all matched the seizure status shown by ECoG. These results confirmed the effectiveness of the combined micro sensors.

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Section: Introductionmentioning

confidence: 99%

Multimodal Detection for Cryptogenic Epileptic Seizures Based on Combined Micro Sensors

Shen

Jiao

et al. 2020

BioMed Research International

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Tailoring Materials for Epilepsy Imaging: From Biomarkers to Imaging Probes

Zhao

Sun

2022

Advanced Materials

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Epilepsy is a recurrent, episodic, and complex neurological syndrome characterized by an enduring predisposition to epileptic seizures and consequent neurological, cognitive, psychological, and social problems. [1] An epileptic seizure is a transient occurrence of symptoms (such as temporary confusion, staring spells, uncontrollable jerking, and loss of awareness) caused by abnormal neuronal electrical activities. [2] As a serious health problem, epilepsy affects ≈1% of the global population, [3] and nearly 5 million people worldwide are diagnosed with epilepsy every year. Although there are now more than 20 antiseizure medications (ASMs) in active clinical use, [4] ≈20-30% of epilepsy patients fail to achieve sustained seizure freedom after adequate trial of two appropriately chosen ASMs. [5] These drugresistant epilepsy (DRE) patients are at an increased risk of injury and death, [6] unbearable medication burden and adverse effects, increased psychiatric and neurocognitive comorbidities, [7] and socioeconomic disadvantage. Therefore, the management of DRE in the clinic is a major challenge.Resection of the epileptic foci (EF), defined as the minimum area of the brain tissue that must be resected or disconnected for the abolishment of seizures, [8] is the most efficient approach for the treatment of DRE patients. [9] First, epilepsy surgery increases the prospects of patients being seizure-free. [10] Approximately 52% of the patients have no disabling seizures for 5 years after surgery, and nearly half of the patients remain free from seizures for 10 years. [11] Second, surgical treatment reduces DRE patients' mortality by two to three times [12] and extends life expectancy by an average of 5 years in comparison to patients who have received drug therapy. [13] Third, epilepsy surgery reduces individual medical expenditures for families. [14] Overall, these results suggest that DRE is potentially curable with surgical intervention. Accurate identification of the EF is a prerequisite for achieving satisfactory postsurgical outcomes. [15] However, only a small percentage of patients is recommended for surgical treatment because of the difficulty in defining EF. First, an initial clinical assessment, including history of epilepsy, semiology information, drug history, and comorbidity, will be performed in the clinic to confirm whether the patients are suitable for surgery. Next, high-resolution structural magnetic resonance imaging (MRI) and long-term inpatient video electroencephalography (EEG) are conducted. [16] If MRI shows Excising epileptic foci (EF) is the most efficient approach for treating drugresistant epilepsy (DRE). However, owing to the vast heterogeneity of epilepsies, EF in one-third of patients cannot be accurately located, even after exhausting all current diagnostic strategies. Therefore, identifying biomarkers that truly represent the status of epilepsy and fabricating probes with high targeting specificity are prerequisites for identifying the "concealed" EF. However, no systematic summary of thi...

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A new method for intraoperative localization of epilepsy focus by means of a gamma probe

Cited by 2 publications

References 8 publications

Multimodal Detection for Cryptogenic Epileptic Seizures Based on Combined Micro Sensors

Multimodal Detection for Cryptogenic Epileptic Seizures Based on Combined Micro Sensors

Tailoring Materials for Epilepsy Imaging: From Biomarkers to Imaging Probes

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