Predicting outcomes in Dandy-Walker malformation: a retrospective cohort study

Dandy-Walker malformation (DWM) is a disorder that most neurologists and neurosurgeons will manage at some point during their careers. It is characterized by partial or complete dysgenesis of the cerebellar vermis. Outcomes are highly variable and range from functionally normal to severely disabled. Predicting these outcomes has classically been focused on the radiological findings that constitute DWM. Other anomalies that can be commonly found in these patients are potentially more indicative of outcome than the tenet markers of DWM. Furthermore, hydrocephalus is an ever-present danger in these patients, many of whom will be admitted to the hospital due to this condition. This study aims to identify these items as potential predictors of outcome.

All referrals from antenatal anatomy scans between 1992 and 2013 that were suspicious for DWM were reviewed. Neurosurgery archives were reviewed for outpatient letters and other correspondence. The number of DWM diagnoses was quantified. Outcomes were judged based on patient status, ranging from death to attending normal school. The presence of any other anomalies was quantified and measured against patient outcomes.

Cyst size and the presence of another CNS anomaly were shown to portend worse outcomes. Non-CNS anomalies and hydrocephalus were not predictive of worse outcomes. Furthermore, of all the treatments assessed, ventriculoperitoneal shunts were shown to be the most effective in this data set.

Results from this study suggest a pivot in how prognoses in DWM should be established and how parents should be counseled, along with a view of hydrocephalus and its treatment that challenges the current literature.