Régis J, Bartolomei F, Hayashi M, Chauvel P
Stereotactic and Functional Neurosurgery Department, Neurophysiology/Neuropsychology INSERM 9926, Timone Hospital, Marseilles, France.
Acta Neurochir Suppl. 2002;84:37-47. doi: 10.1007/978-3-7091-6117-3_4.
The more classical approach for Epilepsy surgery is the removal of the epileptogenic zone (ZE). We present a critical review of information in favor of a possible non-destructive effect of radiosurgery in epilepsy surgery.
Clinical material of patients with epilepsies related to a lesion in highly functional areas subjected to radiosurgery with relief of the seizures and no functional worsening is available. We applied direct treatment of the EZ with good efficacy in the absence of destructive aspects on the MR and no functional deterioration (e.g. hypothalamic hamartomas). Experimental studies have shown biochemical differential effect of radiosurgery on the striatum, glial cell elimination, stem cell migration toward the target area, sprouting,... Plasticity phenomenon are induced by radiosurgery when using non necrotizing dosemetry.
There is clinical and experimental evidence of Gamma Knife capability to induce modulation in the neural system. Detailed mechanism of this modulation and dosemetric parameters enabling to induce such plasticity with no necrosis are still unknown. Subpial transection turning out actually to be quite disappointing, there is a specific rationale to test radiosurgery capability to treat EZ cortex while preserving the underlying function of this cortex when the functional risk for cortectomy is too high.
癫痫手术更为经典的方法是切除致痫区(ZE)。我们对有关放射外科手术在癫痫手术中可能产生非破坏性作用的信息进行了批判性综述。
有与高功能区病变相关的癫痫患者的临床资料,这些患者接受了放射外科手术,癫痫发作得到缓解且功能未恶化。我们对致痫区进行了直接治疗,疗效良好,磁共振成像(MR)上无破坏性表现且无功能恶化(如下丘脑错构瘤)。实验研究表明,放射外科手术对纹状体有生化差异效应、可消除胶质细胞、促使干细胞向靶区迁移、促进轴突发芽等。使用非坏死剂量测定法时,放射外科手术可诱导可塑性现象。
有临床和实验证据表明伽玛刀有能力在神经系统中诱导调节作用。这种调节的详细机制以及能够诱导这种无坏死可塑性的剂量测定参数仍然未知。由于软膜下横切术实际上效果相当令人失望,当皮质切除术的功能风险过高时,有特定的理由来测试放射外科手术治疗致痫区皮质同时保留该皮质潜在功能的能力。