MING-JANG CHIUYEUN-CHUNG CHANGTZU-YU HSIAO2021-03-192021-03-1920040179-051Xhttps://scholars.lib.ntu.edu.tw/handle/123456789/554042Cricopharyngeus (CP) muscle spasm can lead to severe dysphagia. Myotomy of the CP muscle was the treatment of choice. Recently, botulinum toxin type A (BtxA) has been used for CP spasm. It usually brings improvement in deglutition but most patients require reinjection in 3-5 months. We report a 35-year-old man who had an arteriovenous malformation hemorrhage in the brain stem resulting in CP spasm and consequently severe dysphagia. He received BtxA injection and deglutition and nutrition remained good one year after treatment. A literature review analyzing 28 patients and our patient showed negative correlations between age and BtxA dose and between age and duration. Efficacy was positively correlated with duration and BtxA dose was positively correlated with pretreatment severity. In conclusion, physicians would use higher doses on patients with more severe cases but use lower doses on older patients. Those who obtained better posttreatment results would enjoy longer effective duration. Thus, the effective duration of the BtxA is multifactorial.[SDGs]SDG3botulinum toxin A; adult; aged; article; brain arteriovenous malformation; brain hemorrhage; case report; clinical feature; clinical trial; correlation analysis; cricopharyngeal dysphagia; cricopharyngeus muscle; disease course; dose response; drug efficacy; dysphagia; female; human; major clinical study; male; muscle spasm; neurologic examination; pharynx disease; priority journal; treatment indication; treatment outcome; Adult; Aged; Aged, 80 and over; Botulinum Toxins; Deglutition Disorders; Female; Humans; Injections, Intramuscular; Laryngoscopy; Male; Middle Aged; Neuromuscular Agents; Spasm; Tomography, X-Ray Computedjournal article10.1007/s00455-003-0029-3147456472-s2.0-0842327994