Ultrasound assisted versus landmark based intrathecal administration of nusinersen in adults with spinal muscular atrophy disease: A randomized trial.

Introduction/aims: Nusinersen intrathecal administration can be challenging in spinal muscular atrophy (SMA) adults. We aimed to determine if the ultrasound (US)-assistance reduces the number of needle attempts and needle redirections needed for intrathecal drug administration and its impact on the procedure time, the incidence of adverse events (AEs), and patient satisfaction in these patients.

Methods: Fifty-eight patients aged 18 years and older scheduled for intrathecal nusinersen injection were enrolled and randomized (1:1 ratio) into Group 1 (nusinersen infusion with US-assisted technique) or Group 2 (nusinersen infusion with landmark-based technique). The number of attempts, number of redirections, periprocedural time, AEs and patient satisfaction were reported. Continuous variables were compared with the Student t-test or Wilcoxon rank sum test. Categorical variables were evaluated with the Chi-square test or Fisher's exact test in case of expected frequencies <5. The p-values <.05 were considered statistically significant.

Results: There were no statistical differences in the number of attempts, AEs, or patient satisfaction between the two groups. The number of needle redirections was significantly lower in the ultrasound group versus landmark-based group (p < .05) in both the overall group of patients and in the subgroup with difficult spines. The periprocedural time was about 40 seconds longer in US-group versus landmark-based group (p < .05).

Discussion: In SMA adults, US assistance reduces the number of needle redirections needed for intrathecal drug administration. These results suggest that the US assistance may be advantageous for nusinersen therapy to reduce the therapeutic burden of intrathecal infusion.