Description
The authors explicitly state that heterogeneity of MNDs and variability across studies necessitate further research to establish specificity and sensitivity. Without these metrics, the clinical utility of this potential biomarker remains uncertain.
Gap type: open_question Source paper: Motor band sign in (2026, Neurologia, PMID:41455589)
Resolution criteria
Resolution requires: (1) meta-analysis of ≥5 independent cohorts (total n≥1000) reporting sensitivity and specificity of motor band sign on 18F-FDG-PET for ALS vs ALS-mimics vs healthy controls; (2) comparison with gold-standard diagnostic markers (Nfl, Cystatin C); (3) prospective study showing motor band sign predicts progression rate or survival. Studies must use harmonized SUVR thresholds and scanner reconstruction parameters.