Radiographic predictors of deterioration in patients with lumbosacral lipomas

Abstract

OBJECTIVE Although patients with lumbosacral lipomas may be asymptomatic at presentation, most develop neurological symptoms over time. Given the challenges in examining infants, the authors sought to determine whether MRI would be helpful in identifying patients who are more likely to deteriorate early in life and who would potentially benefit from early surgical intervention. METHODS A retrospective review of all patients with lumbosacral lipomas who were seen at the authors' institution between 1997 and 2013 and who were managed without prophylactic surgery was performed. The clinical history and imaging results for each patient were reviewed in detail and then correlated to the pattern of and age at clinical deterioration. RESULTS Twenty-four patients were identified. Nine worsened within the first 18 months of life (early deterioration), and 15 patients deteriorated or remained stable after 30 months (late deterioration/stable). No patients worsened between 18 and 30 months of age. Patients who deteriorated early were more likely to have large intradural lipomas that filled the canal, increased during the 1st year of life, and compressed neurological structures. Some had a syrinx extending above the neural-lipoma interface. Syrinxes in patients with early deterioration were large and expanded in infancy. Patients with early deterioration had motor deficits at the time of deterioration, whereas patients with late deterioration developed mixed urological and motor dysfunction. CONCLUSIONS Patients with large lipomas displacing the cord and an enlarging syrinx have a propensity for early clinical deterioration. Given this, their families may be counseled that 1) the risk of deterioration in infancy may be higher than in infants without these features, and 2) they require more diligent observation. Intervention before deterioration in these infants should also be considered. Patients without these features may be safely observed to a lesser extent.