Skip to main content
Advertisement

Main menu

  • Home
  • Content
    • Current Issue
    • Publication Preview--Ahead of Print
    • Past Issue Archive
    • Case of the Week Archive
    • Classic Case Archive
    • Case of the Month Archive
    • COVID-19 Content and Resources
  • For Authors
  • About Us
    • About AJNR
    • Editors
    • American Society of Neuroradiology
  • Submit a Manuscript
  • Podcasts
    • Subscribe on iTunes
    • Subscribe on Stitcher
  • More
    • Subscribers
    • Permissions
    • Advertisers
    • Alerts
    • Feedback
  • Other Publications
    • ajnr

User menu

  • Subscribe
  • Alerts
  • Log in

Search

  • Advanced search
American Journal of Neuroradiology
American Journal of Neuroradiology

American Journal of Neuroradiology

  • Subscribe
  • Alerts
  • Log in

Advanced Search

  • Home
  • Content
    • Current Issue
    • Publication Preview--Ahead of Print
    • Past Issue Archive
    • Case of the Week Archive
    • Classic Case Archive
    • Case of the Month Archive
    • COVID-19 Content and Resources
  • For Authors
  • About Us
    • About AJNR
    • Editors
    • American Society of Neuroradiology
  • Submit a Manuscript
  • Podcasts
    • Subscribe on iTunes
    • Subscribe on Stitcher
  • More
    • Subscribers
    • Permissions
    • Advertisers
    • Alerts
    • Feedback
  • Follow AJNR on Twitter
  • Visit AJNR on Facebook
  • Follow AJNR on Instagram
  • Join AJNR on LinkedIn
  • RSS Feeds
EditorialEDITORIAL

Death by Nondiagnosis: Why Emergent CT Angiography Should Not Be Done for Patients with Subarachnoid Hemorrhage

David F. Kallmes, Kennith Layton, William F. Marx and Frank Tong
American Journal of Neuroradiology November 2007, 28 (10) 1837-1838; DOI: https://doi.org/10.3174/ajnr.A0809
David F. Kallmes
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Kennith Layton
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
William F. Marx
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Frank Tong
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • Article
  • Info & Metrics
  • References
  • PDF
Loading

As angiographers, we often feel stabs of inadequacy when first reading the many articles promoting the use of CT angiography (CTA) for aneurysm detection. On the basis of the apparently outstanding accuracy of the technique, many centers routinely apply CTA for evaluating patients presenting with subarachnoid hemorrhage.1–3 Management decisions are based on the CTA findings, with direct progression to craniotomy in some or many cases. This imaging and treatment algorithm seems efficient and state-of-the-art for everyone involved. The one individual apparently left out of consideration in this streamlined new-millennium approach is the patient, as far as we can tell.

The most urgent consideration for patients presenting with the suspicion of a ruptured aneurysm is to avoid rehemorrhage, which carries a mortality rate of 80%.4 Unsecured ruptured aneurysms will bleed again frequently. Rates of rehemorrhage are 4% at 24 hours, 20% at 2 weeks, and 50% at 6 months.5 These clinical facts mandate minimizing false-negative rates for any diagnostic examination proposed for imaging patients with suspected ruptured aneurysm. With this in mind, we read with great interest 2 abstracts presented at the 2006 annual meeting of the American Society of Neuroradiology, detailing suboptimal sensitivity of CTA for intracranial aneurysms.6,7 A quick back-of-the-envelope decision analysis, by using the 10% false-negative rate reported in those abstracts applied to a population with 75% prevalence of aneurysms, results in 2.5 additional deaths per 100 patients from rehemorrhage of undiagnosed ruptured aneurysms. Conventional angiography, with near-perfect accuracy and a mortality rate of 0.06%, would result in 0.06 deaths per 100 patients, or less than one fiftieth of the CTA rate.8 For our money, we’ll take conventional angiography any day over CTA.

One could argue that sending all patients with negative findings on CTA on to conventional angiography could “fix” the deficiency of CTA caused by its imperfect sensitivity. We would welcome such a practice pattern. However, we can easily argue that all patients with positive findings on CTA should also go to conventional angiography; this recommendation would mean that every patient with a CTA, positive or negative, should go to conventional angiography.

Patients with CTA examination findings positive for aneurysms should undergo conventional angiography for several reasons. First, most centers now offer endovascular therapy as first-line treatment for ruptured aneurysms. In our opinion, it is difficult or impossible to determine, on the basis of CTA, whether an endovascular approach would be feasible in many cases, and we routinely apply 3D rotational angiography to triage patients to surgery or endovascular treatment. From a purely technical perspective, CTA has a maximum spatial resolution of between 0.35 and 0.5 mm, whereas 3D rotational angiography can resolve vessels between 0.2 and 0.3 mm and conventional digital subtraction angiography (DSA) can resolve vessels as small as 0.1 mm (personal communication, H. Schmitt, PhD, Philips Medical Systems, May 2006). In our opinion, better spatial resolution will naturally lead to improved neck characterization. Recent literature seems to support our bias. Nearly 20% of cases initially thought to be amenable to coiling on the basis of CTA were instead referred for surgery following DSA.2 Furthermore, rates of coiling from series proposing the use of CTA in place of DSA are fairly low, ranging from 20% to 35% of patients being treated with coils rather than surgery.1–3 These low rates of coiling suggest that some patients sent directly to surgery without DSA may have been amenable to coil embolization.

In addition, small important arteries, such as the anterior choroidal artery or the recurrent artery of Heubner, are not identified on CTA. Finally, it remains possible that patients with 1 aneurysm detected on CTA will harbor other undetected aneurysms that were the true source of hemorrhage. Sending such patients directly to surgery, without conventional angiography, leaves these patients at risk for future hemorrhage.

Although we believe CTA is of limited value in a tertiary referral center, there may be reasonable uses for CTA in the other practice environments. For example, if one’s rotational angiography equipment is suboptimal, CTA may assist in determining a working projection for coiling. Also, unstable patients with large intraparenchymal hematomas would benefit from CTA before going directly to surgery. Patients with relatively low pretest probability for aneurysm, such as those with minor trauma, or patients with relative contraindications to angiography, such as patients on warfarin (Coumadin), may reasonably be studied with CTA. In some cases, the choice of anesthesia, either neuroleptic or general, may be based on the probability of detecting an aneurysm, and antecedent CTA may be of benefit. Physicians in hospitals without endovascular therapists might be tempted to perform CTA before transferring patients to appropriate clinical centers that have endovascular capabilities, but even these patients almost certainly will undergo conventional angiography. However, we would argue that all of these instances in which CTA may be reasonable are not usually present in a tertiary care setting.

To review, in the setting of subarachnoid hemorrhage, a negative finding on CTA mandates subsequent conventional angiography on the basis of unacceptable false-negative rates for CTA. Further, a positive finding on CTA also mandates subsequent conventional angiography to further assess aneurysm morphology for triage between endovascular therapy and surgery as well as to detect other aneurysms. If everyone with subarachnoid hemorrhage needs conventional angiography after CTA, then maybe perhaps we should dispense with the CTA all together and just get on with the appropriate test.

References

  1. ↵
    Karamessini MT, Kagadis GC, Petsas T, et al. CT angiography with three-dimensional techniques for the early diagnosis of intracranial aneurysms: comparison with intra-arterial DSA and the surgical findings. Eur J Radiol 2004;49:212–23
    CrossRefPubMed
  2. ↵
    Hoh BL, Cheung AC, Rabinov JD, et al. Results of a prospective protocol of computed tomographic angiography in place of catheter angiography as the only diagnostic and pretreatment planning study for cerebral aneurysms by a combined neurovascular team. Neurosurgery 2004;54:1329–40
    CrossRefPubMed
  3. ↵
    Dehdashti AR, Rufenacht DA, Delavelle J, et al. Therapeutic decision and management of aneurysmal subarachnoid haemorrhage based on computed tomographic angiography. Br J Neurosurg 2003;17:46–53
    CrossRefPubMed
  4. ↵
    Rosenom J, Eskesen V, Schmidt K, et al. The risk of rebleeding from ruptured intracranial aneurysms. J Neurosurg 1987;67:329–32
    PubMed
  5. ↵
    Eskesen V, Rosenorn J, Schmidt K. The impact of rebeleeding on the life time probabilities of different outcomes in patients with ruptured intracranial aneurysms: a theoretical evaluation. Acta Neurochir (Wien) 1988;95:99–101
    CrossRefPubMed
  6. ↵
    Wang LC, Colen T, Cohen W, et al. Evaluation of nontraumatic subarachnoid hemorrhage: CT angiography versus digital subtraction angiography. Presented at: 44th annual meeting of the American Society of Neuroradiology, San Diego, Calif, May 1–5,2006
  7. ↵
    Lane BF, Zoarski GH, Husain MA, et al. Sensitivity of multidetector CT angiography for the detection of intracranial aneurysms. Presented at: 44th annual meeting of the American Society of Neuroradiology, San Diego, Calif, May 1–5,2006
  8. ↵
    Hankey GJ, Warlow CP, Sellar RJ. Cerebral angiographic risk in mild cerebrovascular disease. Stroke 1990;21:209–22
    Abstract/FREE Full Text
  • Copyright © American Society of Neuroradiology
PreviousNext
Back to top

In this issue

American Journal of Neuroradiology: 28 (10)
American Journal of Neuroradiology
Vol. 28, Issue 10
November 2007
  • Table of Contents
  • Index by author
Advertisement
Print
Download PDF
Email Article

Thank you for your interest in spreading the word on American Journal of Neuroradiology.

NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.

Enter multiple addresses on separate lines or separate them with commas.
Death by Nondiagnosis: Why Emergent CT Angiography Should Not Be Done for Patients with Subarachnoid Hemorrhage
(Your Name) has sent you a message from American Journal of Neuroradiology
(Your Name) thought you would like to see the American Journal of Neuroradiology web site.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Citation Tools
Death by Nondiagnosis: Why Emergent CT Angiography Should Not Be Done for Patients with Subarachnoid Hemorrhage
David F. Kallmes, Kennith Layton, William F. Marx, Frank Tong
American Journal of Neuroradiology Nov 2007, 28 (10) 1837-1838; DOI: 10.3174/ajnr.A0809

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
Share
Death by Nondiagnosis: Why Emergent CT Angiography Should Not Be Done for Patients with Subarachnoid Hemorrhage
David F. Kallmes, Kennith Layton, William F. Marx, Frank Tong
American Journal of Neuroradiology Nov 2007, 28 (10) 1837-1838; DOI: 10.3174/ajnr.A0809
Reddit logo Twitter logo Facebook logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Google Plus One
Purchase

Jump to section

  • Article
    • References
  • Info & Metrics
  • References
  • PDF

Related Articles

  • No related articles found.
  • PubMed
  • Google Scholar

Cited By...

  • Use of the 2.8 French Progreat microcatheter in diagnostic cerebral angiography
  • Evaluation of cerebral arteriovenous malformation using 'dual vessel fusion' technology
  • Diagnostic yield of delayed neurovascular imaging in patients with subarachnoid hemorrhage, negative initial CT and catheter angiograms, and a negative 7 day repeat catheter angiogram
  • Use of CT Angiography and Digital Subtraction Angiography in Patients with Ruptured Cerebral Aneurysm: Evaluation of a Large Multihospital Data Base
  • Should American Journal of Neuroradiology Commentary Be Evidence-Based?
  • Cerebral Angiography: Not Yet Ready to Join the Dinosaurs
  • Diagnostic Yield of Catheter Angiography in Patients with Subarachnoid Hemorrhage and Negative Initial Noninvasive Neurovascular Examinations
  • Reply:
  • Reporting standards for endovascular repair of saccular intracranial cerebral aneurysms
  • Reporting Standards for Endovascular Repair of Saccular Intracranial Cerebral Aneurysms
  • Reporting Standards for Endovascular Repair of Saccular Intracranial Cerebral Aneurysms
  • Multi-Detector Row CT Angiography with Direct Intra-Arterial Contrast Injection for the Evaluation of Neurovascular Disease: Technique, Applications, and Initial Experience
  • Coil Embolization of Very Small (2 mm or Smaller) Berry Aneurysms: Feasibility and Technical Issues
  • Crossref
  • Google Scholar

This article has not yet been cited by articles in journals that are participating in Crossref Cited-by Linking.

More in this TOC Section

  • The No Surprises Act: What Neuroradiologists Should Know
  • Call to Action: Women in Neuroradiology’s Group (WINNERS)—Is There a Need?
  • The Z-Shift: A Need for Quality Management System Level Testing and Standardization in Neuroimaging Pipelines
Show more EDITORIAL

Similar Articles

Advertisement

News and Updates

  • Lucien Levy Best Research Article Award
  • Thanks to our 2022 Distinguished Reviewers
  • Press Releases

Resources

  • Evidence-Based Medicine Level Guide
  • How to Participate in a Tweet Chat
  • AJNR Podcast Archive
  • Ideas for Publicizing Your Research
  • Librarian Resources
  • Terms and Conditions

Opportunities

  • Share Your Art in Perspectives
  • Get Peer Review Credit from Publons
  • Moderate a Tweet Chat

American Society of Neuroradiology

  • Neurographics
  • ASNR Annual Meeting
  • Fellowship Portal
  • Position Statements

© 2023 by the American Society of Neuroradiology | Print ISSN: 0195-6108 Online ISSN: 1936-959X

Powered by HighWire