Abbas 2014.

Clinical features and settings	23 consecutive participants attending for CTA and 3D CEUS imaging who were thought to have an endoleak following an EVAR. Type of stents received: bifurcated: 87% (n = 20); uni‐iliac: 13% (n = 3). Aneurysm diameter (mean ± SD): CTA measure: 6.6 ± 1.1 cm; US measure: 6.0 ± 0.97 cm. Setting: tertiary referral vascular centre.
Participants	23 participants; 20 men; age (mean ± SD): 77.4 ± 6 years. Comorbidities: not reported. Geography: UK.
Study design	Retrospective cross‐sectional study; participants were consecutively enrolled.
Target condition and reference standard(s)	Target condition: endoleak. Definition of endoleak: "The 3D reconstruction enables the operator to view the path of the endoleak. The ability to manoeuvre the 3D reconstruction and view the images in sagittal, coronal, and transverse planes simultaneously without moving the probe, enables the operator to accurately identify if flow is within or outside the aneurysm sac." Endoleak (absolute n): 17. Prevalence of endoleak: 56.7% (17/30). Reference standard: CTA. Image acquisition: contrast‐enhanced images obtained on a 16‐slice helical scanner with a 1‐mm slice thickness; CTA from diaphragm to femoral heads performed with participant supine; diameter measured antero‐posterior inner to inner. Type of CT scanner: Siemens Sensation (Siemens Medical, Germany). Use of contrast: 100 mL of iodinated contrast medium Omnipaque 240 (iohexol, 240 mg/mL) administered at flow rate of 3 mL/s. Operator: consultant interventional radiologist.
Index and comparator tests	Index test: 3D CE‐CDUS. Image production: with participants supine, AAA and stent‐graft visualized and traced to proximal neck, which was measured in cross‐section and interrogated for potential endoleak using low colour flow velocity or power Doppler colour flow settings. Type of US: Curefab 3D system comprises tracking sensors installed in transducer of a high‐definition duplex Doppler US system (IU22‐C5) and an electromagnetic box. This technology uses motion tracking mini‐GPS with magnetic field emitter and 2 tracking sensors that transform standard 2D CEUS images into high‐definition 3D format (Curefab, Munich, Germany). Use of contrast: yes, "SonoVue, Bracco, Milan, Italy." Operator: all images reviewed by a research fellow and reported by either an accredited vascular or laboratory technologist. Comparator: 2D CE‐CDUS. Image production: with participants supine, AAA and stent‐graft visualized and traced to proximal neck, which was measured in cross‐section and interrogated for potential endoleak using low colour flow velocity or power Doppler colour flow settings. Type of US: DUS instrument (Philips IU22) with C5‐1 curved array transducer. Use of contrast: yes, "SonoVue, Bracco, Milan, Italy." Operator: all images reviewed by research fellow and reported by either an accredited vascular laboratory technologist.
Follow‐up	No loss to follow‐up, missing data, or adverse events.
Notes	Study based on paired images rather than individual participants. Therefore, 30 paired images from 23 participants analyzed. Participants recruited from South Manchester EVAR surveillance programme between May 2012 and May 2013. Interval between paired images 3.9 ± 2.7 (mean ± SD) weeks. Endoleaks detected in 17 images with CTA, 18 with 2D CEUS, and 18 with 3D CEUS. 2D and 3D CEUS had the same accuracy for the simple detection of an endoleak.
Table of Methodological Quality
Item	Authors' judgement	Description
Representative spectrum? All tests	Yes	Participants consecutively enrolled.
Acceptable reference standard? All tests	Yes	Reference standard was CTA.
Acceptable delay between tests? All tests	No	"The interval between paired images was 3.9 ± 2.7 (mean ± SD) weeks. Range: same day to 8 weeks."
Partial verification avoided? All tests	Yes	Appeared all participants received both tests.
Differential verification avoided? All tests	Yes	All participants who received index test subjected to same reference standard.
Incorporation avoided? All tests	Yes	Index test was not part of the reference standard.
Reference standard results blinded? All tests	Unclear	No description provided.
Index test results blinded? All tests	Unclear	No description provided.
Relevant clinical information? All tests	Yes	Yes.
Uninterpretable results reported? All tests	Yes	No apparent uninterpretable data occurred.
Withdrawals explained? All tests	Yes	No explicit report concerning loss to follow‐up, missing data, or adverse events.