633 Dysregulated REM Sleep in Children with Moebius syndrome

Abstract

Abstract Introduction Moebius syndrome (MBS) is a rare disorder characterized by failure of development of the 6th and 7th cranial nerve nuclei located in the pons. Though the congenital lesion abuts the pontine tegmentum, sleep architecture has not been evaluated in MBS. Methods We report the clinical features of three children with MBS, and discuss implications for “developmental” RBD. Results Three clinically and MRI brain scan-confirmed MBS children, age 0.5 to 16 years, mean 8.5 ± 6.3 years, were evaluated for disrupted sleep, with repetitive crying (1/3), yelling (2/3), agitation in sleep (2/3), and injuring a co-sleeping sibling (1/3); 3/3 had REM sleep without atonia while 2/3 had RBD. REM sleep was reduced in all three: 21.7% in the infant (reference REM percentage value in infancy is about 40%), 11.4% in subject 2 and 3% in subject 3. Treatment with clonazepam (patients 2 and 3) or melatonin (patient 1) had variable results. Conclusion Children with Moebius syndrome have both quantitative (reduced percentage) and qualitative abnormalities of REM sleep (RSWA/RBD). The association of MBS with RSWA/RBD suggests more extensive involvement than published in literature, with extension into the sub-laterodorsal pontine tegmentum and “REM-off” neurons. Moebius syndrome might serve as a model for study of “developmental” REM sleep behavior disorder. Support (if any):