Emergency burr-hole evacuation for subacute SDH with uncal herniation: a case report of near-complete neurological recovery despite bilateral occipital infarction

Introduction and importance: Subacute subdural hematoma (SDH) can remain clinically silent before progressing to fatal herniation. Bilateral fixed dilated pupils in the setting of SDH are traditionally regarded as a near-terminal sign, associated with poor outcomes. Reports of near-complete neurological recovery despite established uncal herniation remain exceedingly rare. This case highlights the importance of rapid decompression as a “brain code” intervention in potentially reversible mass lesions. Case presentation: A previously healthy 47-year-old woman presented with a 2-week history of worsening headaches and intermittent confusion. Initial CT imaging revealed a left frontoparietal subacute SDH with a significant midline shift. While preparing for emergent evacuation, she experienced an abrupt neurological collapse, developing a Glasgow Coma Scale of 3 and bilateral fixed dilated pupils. Immediate burr-hole evacuation resulted in rapid brain relaxation. Postoperatively, she regained full consciousness with a near-complete neurological recovery; however, an MRI confirmed bilateral occipital infarctions resulting in permanent cortical visual impairment. Clinical discussion: This case emphasizes that timely intervention can reverse the physiology of herniation before irreversible brainstem ischemia occurs. While bilateral fixed pupils have been regarded as a sign of futility, aggressive early decompression may provide meaningful recovery in carefully selected patients, especially when deterioration is witnessed and the time to surgery is minimal. Conclusion: Rapid burr-hole evacuation can reverse impending uncal herniation from subacute SDH and result in unexpected but meaningful neurological outcomes in selected patients when deterioration is witnessed and decompression is performed ultra-early. Fixed dilated pupils should not automatically preclude aggressive intervention when the underlying cause is promptly treatable.