Lapalme-Remis Samuel, Cascino Gregory D
Continuum (Minneap Minn). 2016 Oct;22(5, Neuroimaging):1451-1479. doi: 10.1212/CON.0000000000000370.
This article discusses structural and functional neuroimaging findings in patients with seizures and epilepsy. The indications for neuroimaging in these patients and the potential diagnostic utility of these studies are presented.
Patients presenting with new seizures typically require urgent imaging to rule out a critical underlying cause. MRI is the structural neuroimaging procedure of choice in individuals with epilepsy. Specific epilepsy protocols should be considered to increase the diagnostic yield of neuroimaging in patients with structural lesions associated with focal or generalized seizures. Common epileptogenic pathologic processes include mesial temporal sclerosis, malformations of cortical development, focal encephalomacia, primary brain tumors, vascular malformations, and neurocysticercosis. Functional neuroimaging studies are usually restricted to the evaluation of patients with drug-resistant focal epilepsy who are being considered for surgical treatment.
The role of neuroimaging in epilepsy depends on the appropriate clinical indication. In patients without known epilepsy presenting with acute seizures, structural imaging is essential to rule out an underlying etiology (eg, subdural hematoma) that may require a specific therapeutic intervention. In individuals with new or previously uninvestigated epilepsy, MRI serves multiple purposes, including identifying a causative focal lesion and helping to diagnose the epilepsy type. In a significant number of patients with epilepsy, the MRI results are normal or reveal indeterminate findings. For patients with drug-resistant focal epilepsy, functional neuroimaging techniques, such as fludeoxyglucose-positron emission tomography (FDG-PET), ictal single-photon emission computed tomography (SPECT), or functional MRI (fMRI), may assist in surgical planning, especially in patients with MRI-negative epilepsy, whose prognosis for a seizure-free outcome after surgery is worse than for patients with an epileptogenic lesion on structural MRI.
本文讨论癫痫发作和癫痫患者的结构和功能神经影像学研究结果。介绍了这些患者进行神经影像学检查的适应证以及这些研究的潜在诊断价值。
新发癫痫发作的患者通常需要紧急影像学检查以排除潜在的关键病因。MRI是癫痫患者首选的结构神经影像学检查方法。对于与局灶性或全身性癫痫发作相关的结构性病变患者，应考虑采用特定的癫痫检查方案以提高神经影像学的诊断率。常见的致痫性病理过程包括内侧颞叶硬化、皮质发育畸形、局灶性脑软化、原发性脑肿瘤、血管畸形和神经囊尾蚴病。功能神经影像学研究通常仅限于评估考虑手术治疗的药物难治性局灶性癫痫患者。
神经影像学在癫痫中的作用取决于适当的临床适应证。对于无已知癫痫病史而出现急性癫痫发作的患者，结构影像学对于排除可能需要特定治疗干预的潜在病因（如硬膜下血肿）至关重要。对于新发或既往未进行过检查的癫痫患者，MRI具有多种用途，包括识别病因性局灶性病变并有助于诊断癫痫类型。在大量癫痫患者中，MRI结果正常或显示不确定的发现。对于药物难治性局灶性癫痫患者，功能神经影像学技术，如氟脱氧葡萄糖正电子发射断层扫描（FDG-PET）、发作期单光子发射计算机断层扫描（SPECT）或功能MRI（fMRI），可能有助于手术规划，特别是对于MRI阴性癫痫患者，其术后无癫痫发作的预后比结构MRI上有癫痫病灶的患者更差。
