Two Cases of Delayed Post-radiation Lower Cranial Nerve Palsies

J Korean Neurol Assoc > Volume 26(1); 2008 > Article

Journal of the Korean Neurological Association 2008;26(1): 55-58.

방사선 치료 후의 지연성 하부뇌신경마비 2예

박형준, 권기한a 민양기a 서범천b 심동석 김승민 선우일남

연세대학교 의과대학 신경과학교실, 한림대학교 의과대학 신경과학교실a, 성균관대학교 의과대학 강북삼성병원 신경과학교실b

Two Cases of Delayed Post-radiation Lower Cranial Nerve Palsies

Hyung Jun Park

Department of Neurology, Yonsei University College of Medicine; Department of Neurology, Hallym University College of Medicinea; Department of Neurology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicineb, Seoul, Korea

Abstract

Radiation-induced lower cranial neuropathy shows a clinical presentation similar to tumor recurrence or amyotrophic lateral sclerosis. We experienced two patients with bulbar palsies several years after radiotherapy for nasopharyngeal cancer. Brain magnetic resonance imaging showed no evidence of tumor recurrence. Electrophysiologic studies demonstrated mild denervation changes and myokymic discharges in muscles innervated by cranial nerves. Bulbar palsies progressed for 1 year then became stable. We emphasize the importance of myokymic discharges in the differential diagnosis of radiation-induced cranial neuropathy as radiation plexopathies.KeyWords:Radiation, Cranial nerve disease, Myokymia