Pseudosubarachnoid hemorrhage

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A pseudosubarachnoid hemorrhage is an apparent increased attenuation on CT scans within the basal cisterns that mimics a true subarachnoid hemorrhage. [1] This occurs in cases of severe cerebral edema, such as by cerebral hypoxia. It may also occur due to intrathecally administered contrast material, [2] leakage of high-dose intravenous contrast material into the subarachnoid spaces, or in patients with cerebral venous sinus thrombosis, severe meningitis, leptomeningeal carcinomatosis, [3] intracranial hypotension, cerebellar infarctions, or bilateral subdural hematomas. [4]

In a true subarachnoid hemorrhage, there is higher attenuation on CT scans of the basal cisterns, and blood that has leaked from a vessel or formed a hematoma is more highly attenuated due to the absorption of plasma. [5] Pseudosubarachnoid hemorrhages have been observed in as much as 20% of patients resuscitated from non-traumatic cardiopulmonary arrest. Patients with pseudosubarachnoid hemorrhages may have worse prognoses than those with true subarachnoid hemorrhages because of underlying disease processes and decreased cerebral perfusion with elevated intracranial pressure. [6] The identification of a pseudosubarachnoid hemorrhage as opposed to a true subarachnoid hemorrhage may therefore change a patient's treatment plan.[ citation needed ]

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Joshua B. Bederson is an American neurosurgeon, Leonard I. Malis, MD/Corinne and Joseph Graber Professor of Neurosurgery, and Chair of Neurosurgery at the Mount Sinai Health System in New York City. He is a Fellow of the American College of Surgeons and an attending neurosurgeon at The Mount Sinai Hospital and Elmhurst Hospital in Elmhurst, Queens.

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References

  1. Dixon, Andrew. "Pseudosubarachnoid hemorrhage | Radiology Reference Article | Radiopaedia.org". Radiopaedia.
  2. Given, Curtis A.; Burdette, Jonathan H.; Elster, Allen D.; Williams, Daniel W. (1 February 2003). "Pseudo-Subarachnoid Hemorrhage: A Potential Imaging Pitfall Associated with Diffuse Cerebral Edema". AJNR. American Journal of Neuroradiology. 24 (2): 254–256. PMC   7974121 . PMID   12591643.
  3. Marder, Carrie P.; Narla, Vinod; Fink, James R.; Tozer Fink, Kathleen R. (26 December 2013). "Subarachnoid Hemorrhage: Beyond Aneurysms". American Journal of Roentgenology. 202 (1): 25–37. doi:10.2214/AJR.12.9749. PMID   24370126.
  4. Coulier, Bruno (1 March 2018). "Pseudo-subarachnoid Hemorrhage". Journal of the Belgian Society of Radiology. 102 (1): 32. doi: 10.5334/jbsr.1509 . PMC   6032606 . PMID   30039044.
  5. Ramanathan, Ramnath Santosh (2018). "Pseudo-subarachnoid Hemorrhage Sign". Annals of Indian Academy of Neurology. 21 (1): 83–84. doi: 10.4103/aian.AIAN_152_17 . PMC   5909155 . PMID   29720807.
  6. "Pseudo-Subarachnoid Hemorrhage after Cardiac Arrest". The Western Journal of Emergency Medicine. 31 May 2020.

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