Introduction: Postoperative acute cerebellar swelling (ACS) is a potential life-threatening complication of posterior fossa surgery. ACS pathogenesis has not been fully elucidated yet, but postoperative swollen tissues, especially in case of residual tumor, and venous congestion seem to play a pivotal role leading to a kind of posterior fossa compartment syndrome. Early wide suboccipital decompressive craniectomy (SDC) is proposed as a life-saving procedure that should be considered even for patients in very critical conditions.

Methods: A retrospective analysis included 8 patients that underwent emergency SDC for ACS following posterior fossa surgery. All patients presented rapid onset of worsening sympotms leading to a comatose status (GCS range 3-5). As soon as ACS was diagnosed, both clinically and radiologically, immediate external ventricular drainage positioning (if not already present) and wide SDC (from sigmoid sinus to sigmoid sinus with removal of the posterior arch of C1 and dural opening) were performed.

Results: The 8 patients included underwent posterior fossa surgery for the following pathologies: 3 meningiomas, 2 pineal tumors, 1 cerebellar metastasis, 1 schwannoma, 1 ependymoma. Mortality rate due to ACS was 25% (2/8), while 6/8 (75%) patient survived following emergency SDC. Of these, 1 (12.5%) died due to tumor progression and 1 died due to infection more than 1 month after SDC. Of the other 6 patients, at hospital discharge 3 (37.5% overall) were severely disabled (KPS 30-40, mRS 4-5) and 3 were able to carry on normal activity and to work (KPS 100-80, mRS 1-3).

Conclusions: Once postoperative ACS develops, even in patients in very critical conditions, early and wide SDC is the only therapeutic option that can obtain sudden brainstem decompression, resulting in a life-saving procedure.

Patient Care: The promptly diagnosis of postoperative ACS may lead to very early posterior fossa decompression. This can give a chance of survival, or in some cases even of recover, to patients in desperate clinical conditions

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of postoperative acute cerebellar swelling, 2) Discuss, in small groups, how to promptly recognise ACS 3) Identify an effective treatment for ACS"

References: Bertalanffy H. Avoidance of postoperative acute cerebellar swelling after pineal tumor surgery. Acta Neurochir (Wien). 2016 Jan;158(1):59-62. .