Comparing diagnostic accuracy of 18F-FDG-PET/CT, contrast enhanced CT and combined imaging in patients with suspected vascular graft infections

Lars Husmann, Martin W Huellner, Bruno Ledergerber, Alexia Anagnostopoulos, Paul Stolzmann, Bert-Ram Sah, Irene A Burger, Zoran Rancic, Barbara Hasse, and the Vasgra Cohort, Lars Husmann, Martin W Huellner, Bruno Ledergerber, Alexia Anagnostopoulos, Paul Stolzmann, Bert-Ram Sah, Irene A Burger, Zoran Rancic, Barbara Hasse, and the Vasgra Cohort

Abstract

Background: To evaluate the diagnostic accuracy of positron emission tomography/computed tomography with 18F-fluorodeoxyglucose (PET/CT), contrast-enhanced CT (CE-CT), and a combined imaging approach (CE-PET/CT) in patients with suspected vascular graft infection (VGI).

Methods: PET/CT and CE-CT were performed prospectively in 23 patients with suspected VGI. Diagnostic accuracy for PET/CT was assessed by using previously suggested cut-off points for maximum standardized uptake values (SUVmax) measured in the vicinity of the graft. Using a new 4-point scale for visual grading, two readers independently assessed the diagnostic accuracy for CE-CT and combined CE-PET/CT. Microbiological culture, obtained after open biopsy or graft explantation, and clinical follow-up of the patients served as the standard of reference.

Results: Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and accuracy of PET/CT for the diagnosis of VGI was 100%, 50%, 100%, 72.2%, and 78.3%, using the most favorable SUVmax cut-off ≥ 4.9. Respective values for CE-CT were 100%, 50%, 100%, 72.2%, and 78.3% for reader 1, and 92.3%, 80%, 88.9%, 85.7%, and 86.9% for reader 2; while respective values for combined CE-PET/CT were 100%, 70%, 100%, 81.3%, and 86.9% for reader 1, and 100%, 80%, 100%, 86.7%, and 91.3% for reader 2. Additionally, imaging provided a conclusive clinical diagnosis in patients without graft infection (i.e., other sites of infection): five of ten patients with CE-CT, six of ten patients with PET/CT, and seven of ten patients with combined CE-PET/CT.

Conclusion: The diagnostic accuracy of combined CE-PET/CT in patients with suspected VGI is very high. The combination of the high sensitivity of PET/CT in detecting metabolically active foci in infection, and the high specificity of CE-CT in detecting anatomic alterations, appears to be the reason why combined imaging outperforms stand-alone imaging in diagnosing VGI and may be supportive in future decision-making of difficult cases of suspected VGI. Clinical Trials.gov Identifier: NCT01821664.

Keywords: CT; Diagnostic accuracy; FDG; PET/CT; Vascular graft infection.

References

    1. Eur J Nucl Med. 2000 Jul;27(7):822-32
    1. J Vasc Surg. 2005 Nov;42(5):919-25
    1. Br J Radiol. 2007 Jun;80(954):437-45
    1. J Nucl Med. 2007 Aug;48(8):1230-6
    1. Eur J Nucl Med Mol Imaging. 2009 May;36(5):850-8
    1. Eur J Vasc Endovasc Surg. 2010 Sep;40(3):348-54
    1. Semin Vasc Surg. 2011 Dec;24(4):182-90
    1. Radiology. 1990 Apr;175(1):157-62
    1. Eur J Cardiothorac Surg. 2013 Jun;43(6):1183-7
    1. Swiss Med Wkly. 2013 Jan 24;143:w13754
    1. Semin Nucl Med. 2013 Sep;43(5):396-402
    1. J Nucl Med. 2014 Mar;55(3):392-5
    1. J Clin Oncol. 2014 Sep 20;32(27):3059-68
    1. J Vasc Surg. 2015 Apr;61(4):965-71
    1. Eur J Vasc Endovasc Surg. 2015 Apr;49(4):455-64
    1. Circulation. 2015 Sep 22;132(12):1113-26
    1. Circulation. 2016 Nov 15;134(20):e412-e460
    1. Eur J Vasc Endovasc Surg. 2016 Dec;52(6):758-763
    1. J Nucl Med. 2017 Nov;58(11):1827-1830
    1. Zentralbl Chir. 2017 Oct;142(5):502-505
    1. J Vasc Surg. 1997 Feb;25(2):277-84; discussion 285-6

Source: PubMed

3
Předplatit