肌阵挛失神癫癎临床及脑电图特征

目的 肌阵挛失神癫癎(epilepsy with myoclonic absences,EMA)是一种以肌阵挛失神(myoclonic absences,MA)为主要发作类型的儿童癫癎综合征.本研究旨在探讨EMA的临床及神经电生理特征.方法 对6例EMA患儿均进行视频脑电图(VEEG)监测,2例同步监测双侧三角肌肌电图(EMG).对EMA的临床、神经电生理特征、治疗及预后进行分析.结果 6例中女3例,男3例.起病年龄为2岁3个月～11岁,平均5岁2个月.5例以MA为惟一发作类型,1例以全身强直-阵挛发作起病,后转变为MA.MA临床表现为:不同程度意识改变,上肢为主的节律性肌阵挛抽搐、常伴强直性收缩、有时可见头及身体的偏斜或不对称抽搐,持续时间为2～30 s,发作突发突止,发作频繁时每日可达数次～30余次,过度换气常可诱发.所有患儿发作期EEG为双侧对称同步的3 Hz棘慢波节律性暴发,2例双侧三角肌EMG记录到与发作期放电频率一致的节律性肌电暴发,其中1例还记录到伴随的持续强直性肌电活动.所有患儿发作间期EEG均有醒睡各期全导棘慢波发放,部分存在少量局灶性放电.治疗主要采用丙戊酸单药或联合其他抗癫癎药.随访时年龄为6岁4个月～19岁,4例发作控制8个月～3年;1例因开始治疗晚、1例未及时正规治疗并伴病程中全身强直-阵挛发作,分别随访2年半及5年,目前仍有发作,且有智力受损.结论 EMA为一种少见的儿童癫癎性疾病,发作类型主要为MA.临床表现结合发作期VEEG及同步EMG可确诊MA.早期恰当的选用丙戊酸或联合其他抗癫癎药对EMA有效.治疗不及时或伴有全身强直-阵挛发作时预后相对不良.

Clinical and electroencephalographic characteristics of epilepsy with myoclonic absences

Objective Epilepsy with myoclonic absences (EMA) is a type of childhood epilepsy characterized by a specific seizure type, i.e. myoclonic absences (MA). This study aimed to investigate the clinical and electrophysiological characteristics of EMA. Method Video-EEG monitoring was carried out in 6 patients with EMA, and 2 of them were examined with simultaneous deltoid muscle surface electromyogram (EMG). The clinical and EEG characteristics, treatment and prognoses of EMA were analyzed. Result Of the 6 patients, 3 were female, and 3 were male. The age of onset was from 2 years and 3 months to 11 years (average 5 years and 2 months). MA was the sole seizure type in 5 patients. One patient presented generalized tonic clonic seizures (GTCS) at the onset and then switched to MA. The manifestations of MA included an impairment of consciousness of variable intensity, rhythmic myoclonic jerks with evident tonic contraction mainly involving the upper extremities, a deviation of head and body to one side or asymmetrical jerks observed in some cases, a duration ranging from 2 to 30 s, an abrupt onset and termination, a high frequency of attacks, at least several times to over 30 times per day, and easily provoked by hyperventilation. The ictal EEG consisted of rhythmic 3 Hz spike and wave discharges that were bilateral, synchronous and symmetrical in all patients. The deltoid muscle EMG recording in 2 patients showed rhythmic myoclonus at the same frequency as the spike and waves. The interictal EEG showed generalized spike and wave discharges in all patients, and focal discharges in some patients. Valproate was the drug of choice, which was often combined with other antiepileptic drugs. The ages at follow up ranged from 6 years and 4 months to 19 years. Seizures were controlled from 8 months to 3 years in 4 cases. The treatment at the onset was late in one case and was irregular in another who had GTCS during the course of the disease. These two cases were followed up for 2 years and 6 months and 5 years, respectively. Seizures could not be controlled in the 2 patients with intellectual impairment. Conclusion EMA was a rare type of childhood epilepsy characterized by MA. Clinical observation and ictal video-EEG and EMG were essential to diagnose EMA. Valproate alone or combined with other antiepileptie drugs given early could have a favorable effect to EMA. Delayed therapy and the presence of GTCS might suggest poor prognosis.