Department of Neurology and Psychiatry, Assiut University Hospital, Assiut, Egypt.
J Clin Neurophysiol. 2019 Sep;36(5):385-388. doi: 10.1097/WNP.0000000000000592.
The "A" wave is a compound action potential evoked consistently from a muscle by submaximal electric stimulation to the nerve. "A" waves were usually associated with the presence of conduction block and abounded in lower limbs more than in upper limbs. Guillain Barre syndrome is an autoimmune polyradiculoneuropathy that usually follows respiratory or gastrointestinal infections.
To study the prognostic value of "A" waves in patients with Guillain Barre syndrome with different recovery patterns.
In this study, 50 patients with GuillainBarreSyndrome were enrolled. They were divided into two groups based on the presence or absence of "A" waves in their neurophysiologic study at onset of illness. Strength of limb muscles of the involved patients was assessed at onset of the study and 6 weeks later (short-term clinical recovery) using the Medical Research Council Scale.
Patients with waves (29 patients: 58%) showed poorer short-term follow-up parameters than those without "A" waves (21 patients: 42%).
Presence of "A" waves is usually associated with conduction block and marked degree of demyelination. "A" waves carry poor prognostic value in short-term follow-up parameters in patients with Guillain Barre syndrome.
“A”波是一种复合动作电位，通过对神经进行亚最大电刺激，可从肌肉中持续引出。“A”波通常与传导阻滞有关，在下肢比在上肢更为常见。格林-巴利综合征是一种自身免疫性多发神经根神经病，通常继发于呼吸道或胃肠道感染。
研究不同恢复模式的格林-巴利综合征患者“A”波的预后价值。
本研究纳入了 50 例格林-巴利综合征患者。根据疾病发病时神经生理研究中是否存在“A”波，将他们分为两组。在研究开始时和 6 周后（短期临床恢复），使用医学研究委员会量表评估受累肢体肌肉的力量。
存在“A”波的患者（29 例：58%）短期随访参数比不存在“A”波的患者（21 例：42%）差。
“A”波的存在通常与传导阻滞和明显的脱髓鞘程度有关。在格林-巴利综合征患者的短期随访参数中，“A”波具有较差的预后价值。
