Functional Outcomes After Decompressive Surgery in Patients with Malignant Space-Occupying Cerebellar Infarction

<b>Background and Purpose</b>: Decompressive surgery is a potentially life-saving treatment in patients with malignant space-occupying cerebellar infarction. However, there is only limited literature on functional outcomes and complications after surgery. Our aim was to establish markers which predict poor outcome. <b>Methods</b>: We retrospectively analyzed data of all patients who underwent surgery due to malignant swelling of a space-occupying cerebellar infarction in our hospital between 2005 and 2023. Statistical analyses were conducted on multiple parameters to identify predictors of poor functional outcome (mRS 4-6) 90 days after surgery. Complications during hospitalization were reviewed for each patient. <b>Results</b>: In total, 58 patients received decompressive surgery. The 90-day mortality rate was 27.6% (n = 16). A good functional outcome (mRS 0-3) 90 days after surgery was achieved in 24 patients (41.4%). Multivariable analysis revealed multiple factors associated with a poor outcome on day 90 (mRS 4-6): a higher premorbid mRS score (OR 2.715 [95% CI, 1.166-6.323]; <i>p</i> = 0.021), higher NIHSS score on admission (OR 1.088 [95% CI, 1.014, 1.168]; <i>p</i> = 0.019) and the presence of an additional brainstem infarction (OR 7.035, [95% CI, 1.255, 39.424], <i>p</i> = 0.027). Hyperactive delirium was associated with good clinical outcome (OR 0.020 [95%CI, 0.001-0.623]; <i>p</i> = 0.026). Aspiration pneumonia (n = 22, 37.9%), urinary tract infection (n = 15, 25.9%), and hyperactive delirium (n = 8, 13.8%) were the most common complications during hospitalization. <b>Conclusions</b>: Decompressive surgery is a safe, life-saving treatment for malignant space-occupying cerebellar infarction. Higher premorbid mRS, higher NIHSS score on admission and the presence of brainstem infarction are associated with a poor functional outcome.