Abstract:ObjectiveTo observe the efficacy and side effects of Nusinersen in the treatment of spinal muscular atrophy (SMA). Methods A retrospective analysis was made for the clinical data of 12 SMA children admitted to Department of Neurology of Schneider Children′s Medical Center in Israel from September 2017 to March 2018.By gene detection,all the children were confirmed to suffer from the deletion of exon 7 of survival motor neuron gene (SMN1) and no mutation of SMN1 heterozygote.Nusinersen (12-mg loading dose) intrathecal injection via lumbar puncture was performed.The first four intrathecal injections were given at 1-,15-,30- and 60- day respectively,and the maintenance doses(12 mg) were given every 4 months.On 181 days,the improvement of motor function were evaluated by Children′s Hospital of Philadelphia Infant Test of Neuromuscular Disorders(CHOP-INTEND) and Hammersmith Functional Motor Scale Expanded (HFMSE). Results After 181 days of treatment,in 4 patients with early onset SMA-I,CHOP-INTEND score increased by 3 and 5 points in 2 patients,and muscle tension improved in other 2 patients significantly;in 8 patients with late onset SMA-Ⅱ,SMA-Ⅲ and SMA-Ⅳ,HFMSE score increased in different extent with an average increase of 4.1 points (3.1-5.2).Adverse reactions were less and mild. Conclusion Nusinersen is effective and safe in the treatment of spinal muscular atrophy.