Neuroimaging in deteriorating patients with cerebellar infarcts and mass effect

Background and Purpose - The decision to proceed with surgery in cerebellar infarct with mass effect (CIMASS) in deteriorating patients is based on clinical features. The potential role of neuroimaging in predicting deterioration has not been systematically studied. In this study we determine the role of neuroimaging in predicting deterioration in CIMASS. Methods - We retrospectively reviewed the clinical and neuroimaging features in 90 patients with cerebellar infarcts. We selected for detailed analysis CIMASS in 35 patients. Results - Eighteen patients remained stable and 17 deteriorated. Of these 17 patients, 8 were treated conservatively and 9 had surgery. Radiological features indicative of progression were more common in deteriorating patients compared with stable patients: fourth ventricular shift (82.3% versus 50%, P=0.075, OR=4.67), hydrocephalus (76.5% versus 11.1%, P=0.0001, OR=26), brain stem deformity (47% versus 5.6%, P=0.0065, OR=15.1), and basal cistern compression (35.3% versus 0%, P=0.0076, OR=20.91). Differences in upward displacement of the aqueduct and pontomesencephalic junction from Twining's line, tonsillar descent on sagittal MRI, and infarct volumes between stable and deteriorating patients were not statistically significant. Conclusions - Hydrocephalus, brain stem deformity, and basal cistern compression may herald deterioration in CIMASS. Admission to a neurological-neurosurgical intensive care unit and consideration of preemptive surgery are warranted in these patients. Vertical displacement of tonsils or aqueduct, demonstrated by MR imaging, did not predict deterioration.