Enhancing subdural effusions mimicking acute subdural hematomas following angiography and endovascular procedures: report of 2 cases

J Neurosurg. 2015 Nov;123(5):1184-7. doi: 10.3171/2014.10.JNS142172. Epub 2015 Apr 24.


Hyperdense enhancing subdural effusion due to contrast extravasation has been recently described as a potential mimicker of acute subdural hematoma following a percutaneous coronary procedure. Herein, the authors report on 2 patients who presented with subarachnoid hemorrhage from ruptured cerebral aneurysms and who developed enhancing subdural effusions mimicking acute subdural hematomas after angiography and endovascular coil placement. In 1 case, the subdural effusions completely cleared but recurred after a second angiography. CT attenuation values higher than expected for blood, as well as the evolution of the effusions and density over time, allowed for differentiation of enhancing subdural effusions from acute subdural hematomas.

Keywords: HU = Hounsfield unit(s); aneurysm; mimic; rupture; subarachnoid hemorrhage; subdural effusion; subdural hematoma; trauma; vascular disorders.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Aneurysm, Ruptured / complications
  • Aneurysm, Ruptured / surgery
  • Cerebral Angiography
  • Diagnosis, Differential
  • Disease Progression
  • Endovascular Procedures / adverse effects
  • Endovascular Procedures / methods*
  • Fatal Outcome
  • Female
  • Hematoma, Subdural, Acute / diagnosis
  • Hematoma, Subdural, Acute / etiology*
  • Hematoma, Subdural, Acute / surgery*
  • Humans
  • Male
  • Middle Aged
  • Postoperative Complications / diagnosis
  • Postoperative Complications / etiology
  • Postoperative Complications / surgery
  • Stents
  • Subarachnoid Hemorrhage / complications
  • Subarachnoid Hemorrhage / surgery
  • Subdural Effusion / diagnosis
  • Subdural Effusion / etiology*
  • Subdural Effusion / surgery*
  • Treatment Outcome