Vrije Universiteit Brussel
Extensive cerebral venous sinus thrombosis with subarachnoid densities on NECT:
subarachnoid versus pseudosubarachnoid haemorrhage
Baetslé, Amaury; Wiels, Wietse; Raeymaeckers, Steven; De Mey, Johan
Published in:
European Radiology (Luxembourg)
DOI:
10.35100/eurorad/case.17309
Publication date:
2021
License:
CC BY-NC-SA
Document Version:
Final published version Link to publication
Citation for published version (APA):
Baetslé, A., Wiels, W., Raeymaeckers, S., & De Mey, J. (2021). Extensive cerebral venous sinus thrombosis with subarachnoid densities on NECT: subarachnoid versus pseudosubarachnoid haemorrhage. European Radiology (Luxembourg), 2021. https://doi.org/10.35100/eurorad/case.17309
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Download date: 07. Apr. 2022
Case 17309
Extensive cerebral venous sinus thrombosis with subarachnoid densities on NECT: subarachnoid versus pseudosubarachnoid
haemorrhage
Published on 22.06.2021
DOI: 10.35100/eurorad/case.17309 ISSN: 1563-4086
Section: Neuroradiology
Area of Interest: Artificial Intelligence Emergency Neuroradiology brain
Imaging Technique: CT Imaging Technique: MR Case Type: Clinical Cases
Authors: Amaury Baetslé, Wietse Wiels, Steven Raeymaeckers, Johan de Mey
Patient: 44 years, female Clinical History:
A 44-year-old female patient with no significant medical history presented to the ER with unusual multifocal neurologic manifestations: mild anisocoria, echolalic speech and right-sided facial paresis.
Imaging Findings:
A non-enhanced CT (NECT) of the brain was performed (Figure 1) and demonstrated bilateral sulcal densities without the involvement of the basal cisterns. A commercially available AI program (Aidoc, Intracranial
haemorrhage) also identified these densities as potential haemorrhages. Since we would not expect disseminated bilateral subarachnoid haemorrhages (SAH) without the context of trauma, a contrast-enhanced CT venography was performed (Figure 2). This demonstrated an extensive thrombosis of the sinus sagittalis superior and right-sided sinus transversus and sigmoïdeus (CVST). We concluded this to be proof of a pseudosubarachnoid haemorrhage.
Consequent MRI demonstrated subarachnoid hyperintensities on fluid-attenuated inversion recovery (FLAIR) and associated loss of signal on susceptibility-weighted imaging (SWI) (Figure 3 and 4). These findings then suggested a component of underlying SAH. Contrast-enhanced MR venography confirmed the presence of a CVST in the superior sagittal and transverse sinus (Figure 5).
Discussion:
Background
The extravasation of blood into the subarachnoid space is called a subarachnoid haemorrhage (SAH) and presents as hyperdensities in the subarachnoid space on NECT. A wide range of clinical manifestations aside from
thunderclap headache may occur. Most SAH’s have a traumatic or vasculopathic (often aneurysmal) aetiology.
Aneurysmal bleeding has several distinct patterns, none of which were present in our patient. An increased attenuation within the basal cisterns without the presence of a true SAH is called a pseudosubarachnoid
haemorrhage and can mimic SAH. These densities are usually symmetrical with sparing of the sulcal region. It is caused by the dilatation of superficial venous structures within the subarachnoid space. Pseudosubarachnoid haemorrhage is commonly associated with cerebral oedema, but can also be seen in cases of severe meningitis and CVST [1]. A large bilateral subdural haemorrhage can also be responsible for effacement of sulci and basal cisterns and thus give rise to the false notion of blood in the subarachnoid space [2]. Lastly, intrathecal contrast medium can also mimic a subarachnoid haemorrhage.
Clinical Perspective
Imaging is required for the diagnosis of SAH and mimicking conditions, as both can present a wide spectrum of clinical manifestations.
Imaging Perspective
A SAH will most often be easy to recognize on a NECT. However, identifying the aetiology of the bleeding can be challenging. Antecedents of trauma are usually known to the clinician. Spontaneous cases of SAH are often of vascular origin, which may present typical patterns [3].
When the SAH is confined to parasagittal or dorsolateral cerebral convexity and when the basal cisterns remain normal, pseudosubarachnoid haemorrhage due to CVST or oedema should be considered [4]. On MRI, a recent SAH can be demonstrated as hyperintensities in the subarachnoid space on fluid-attenuated inversion recovery (FLAIR) sequence. SAH and CSVT will also show susceptibility-weighted artefacts [5]. If NECT or MRI can't differentiate a true SAH from a pseudo-SAH, a lumbar puncture can be helpful since elevated xanthochromia in cerebrospinal fluid is pathognomonic for SAH [6].
Outcome
Our patient was treated with anticoagulants and showed full recovery at 6-month follow-up
Take-Home Message / Teaching Points
CVST can be associated both with true SAH as well as pseudosubarachnoid haemorrhage. MRI or lumbar punction can be helpful to distinguish both diagnoses. CVST should immediately be treated with anticoagulants, even if some brain bleeding is present.
Written informed patient consent for publication has been obtained.
Differential Diagnosis List: Extensive cerebral venous sinus thrombosis with subarachnoid haemorrhage, Pseudosubarachnoid haemorrhage, Cerebral oedema, Severe meningitis, Large bilateral subdural haemorrhage, Intrathecal contrast
Final Diagnosis: Extensive cerebral venous sinus thrombosis with subarachnoid haemorrhage References:
Given CA 2nd, Burdette JH, Elster AD, Williams DW 3rd. (2003) Pseudo-subarachnoid hemorrhage: a potential imaging pitfall associated with diffuse cerebral edema. AJNR Am J Neuroradiol. 2003 Feb; 24 (2): 254-6. (PMID:
12591643)
Rabinstein AA, Pittock SJ, Miller GM et-al. (2003) Pseudosubarachnoid haemorrhage in subdural haematoma. J.
Neurol. Neurosurg. Psychiatr. 2003;74 (8): 1131-2. (PMID: 12876252)
Marder CP, Narla V, Fink JR et-al. Subarachnoid hemorrhage: beyond aneurysms. (2014) AJR Am J Roentgenol.
2014;202 (1): 25-37. (PMID: 24370126)
Ali Hassan, Bakhtiar Ahmad, Zahoor Ahmed, Khalid W Al-Quliti. (2015) Acute subarachnoid hemorrhage. An unusual clinical presentation of cerebral venous sinus thrombosis. Neurosciences (Riyadh). 2015 Jan;20(1):61-4.
(PMID: 25630784)
Boukobza, M., Crassard, I., Bousser, MG. et al. (2016) Radiological findings in cerebral venous thrombosis
presenting as subarachnoid hemorrhage: a series of 22 cases. Neuroradiology 58, 11–16 (2016). (PMID: 26376804) Evie Marcolini, Jason Hine (2019) Approach to the Diagnosis and Management of Subarachnoid Hemorrhage. West J Emerg Med. 2019 Mar;20(2):203-211. (PMID: 30881537)
Figure 1
a
Description: Non-contrast-enhanced CT of the brain, axial plane. Sulcal densities in the right parietal lobe (blue arrow). Also, note the discrete hyperdensity of the sinus sagittalis superior (green arrow) Origin: Department of Radiology, UZ Brussel, Jette, 2021
Figure 2
a
Description: Contrast-enhanced CT of the brain, venography, sagittal plane. Note the absent enhancement of the sinus sagittalis superior (red arrows) as opposed to the sinus rectus (blue arrow) Origin: Department of Radiology, UZ Brussel, Jette, 2021
Figure 3
a
Description: Fluid-attenuated inversion recovery (FLAIR) sequence demonstrates hyperintensities in the right frontal and bilateral parietal subarachnoid space Origin: Department of Radiology, UZ Brussel, Jette, 2021
Figure 4
a
Description: Susceptibility-weighted imaging demonstrates loss of signal in the right frontal and parietal subarachnoid spaces (red arrows) as well as in the cerebral sinus (blue arrow)Origin:
Department of Radiology, UZ Brussel, Jette, 2021
Figure 5
a
Description: Contrast MR venography confirms the presence of thrombotic material in the superior sagittal sinus Origin: Department of Radiology, UZ Brussel, Jette, 2021
