Postural Sway Predicts Growth in Untreated Vestibular Schwannoma: A Retrospective Volumetric Study.
One in three vestibular schwannomas (VS) will grow within 3 years after diagnosis, but no reliable baseline parameter has been found to predict such growth.To determine if postural sway is associated with growth of untreated VS.Patients with newly diagnosed sporadic VS assigned to a wait-and-scan protocol were identified from a prospectively maintained database. Postural sway was measured by posturography at baseline and patients were classified as steady or unsteady. Observer-blinded volumetric tumor measurements were performed on the diagnostic MRI and a 3-year control MRI. Tumor growth quantified as relative growth (%) and volume-doubling time (VDT and VDT-1) were investigated as dependent variables against baseline parameters.Out of 204 VS patients, 53 (26%) were classified as unsteady on the platform at baseline. Median tumor volume was 0.32 cm3 (range 0.02-4.79), and 51% demonstrated significant growth within 3 years. Unsteady patients had significantly faster-growing tumors, with a mean relative growth of 172.5% compared to 79.5% in steady patients (p 20% volume increase, compared to 42% in steady patients (p