Ultrasound assisted lumbar intrathecal administration of nusinersen in adult patients with spinal muscular atrophy: A case series

Introduction/Aims Intrathecal nusinersen administration can be challenging in certain adult spinal muscular atrophy (SMA) patients with difficult spinal anatomy who require imaging techniques (fluoroscopy or computed tomography scans) or invasive approaches (catheter placement, laminotomy) to identify the intrathecal space. We used ultrasound (US) assistance to access the lumbar intrathecal space in patients with SMA who experienced previous difficulties or failures with intrathecal dosing. Methods Eighteen adult patients with difficult spines were enrolled. We used US assistance, and we recorded the successful administrations, number of attempts, procedure times, and "patient satisfaction." Results There were 57 consecutive successful nusinersen spinal administrations in all patients enrolled. In 50% of patients, two or fewer attempts were needed to obtain a successful administration, with four or fewer attempts in 83.3%; only three patients reported more than four attempts because of both severe scoliosis and severe spine rotation (two patients) and obesity (one patient). The mean procedure time was 11.8 min (range, 1.7-28.9). Patient satisfaction was 4.97/5 (range, 4-5; median, 5) on Likert scale at 5 min and at 72 h. No major adverse events were reported, and two post dural puncture headaches were managed with medical therapy and with complete resolution within 72 h. Discussion US assistance seems to be a valid option among treatment choices for intrathecal nusinersen administration in patients with difficult spine. The absence of radiation exposure and the lack of need for intravenous sedation or general anesthesia are additional potential advantages to US assisted administration.