Chiari Formation or Malformation? Trends in the Pathophysiology and Surgical Treatment of an Ever-Elusive Entity.

: Chiari malformation type 1 (CM1) remains a complex neurosurgical condition with ongoing debate regarding its optimal management. : This narrative review examines key controversies surrounding the pathophysiology, surgical indications, and treatment strategies for CM1. : We highlight the challenges posed by the wide spectrum of CM variants and the evolving understanding of its association with syringomyelia, basilar invagination, and craniovertebral instability. Emerging surgical techniques, including minimally invasive approaches and the use of new technologies such as endoscopes and exoscopes, are evaluated for their potential to improve outcomes. Recent consensus guidelines are also discussed. : The need for individualized treatment plans for CM1 is emphasized, with special focus put on the connection between novel pathophysiological insights, technological advancements and opportunities for a more nuanced surgical management. Further research is necessary to establish solid foundations for more individualized treatments.