Posterior reversible encephalopathy syndrome after trigeminal microvascular decompression: A case report.

Background: Reversible posterior encephalopathy syndrome (PRES) is a clinical and radiological entity resulting from cerebral vascular dysregulation and disruption of the blood-brain barrier. It is characterized by neurological symptoms such as seizures, headaches, altered mental status, and visual disturbances. Although PRES is usually reversible when identified promptly and treated appropriately, delays in recognition may lead to severe complications or permanent deficits. The syndrome is considered uncommon as a postoperative complication and, within neurosurgery, has mostly been described after posterior fossa procedures. Case Description: We present the case of a patient who developed PRES following microvascular decompression of the trigeminal nerve root, performed for classical trigeminal neuralgia. To the best of our knowledge, this is the first reported occurrence of PRES after this specific surgical intervention. The patient developed acute neurological changes in the immediate postoperative period, leading to the diagnosis of PRES. Radiological findings supported the clinical impression, and appropriate management led to gradual neurological recovery. Conclusion: In this case, several postoperative factors likely contributed to the onset of PRES, including acute arterial hypertension, insufficient pain control, and potential manipulation of structures adjacent to the brainstem during surgery. This highlights the multifactorial nature of PRES and the importance of considering it in the differential diagnosis when unexplained neurological symptoms occur after cranial surgery. Increasing awareness of PRES as a possible complication of microvascular decompression may allow for earlier recognition, prompt management, and ultimately improved outcomes for patients undergoing such procedures.