Arsicot 2014.

Clinical features and settings	75 consecutive participants treated with EVAR for infrarenal AAA, representing 116 pairs of examinations (3D US and CTA). Type of stents received: Anaconda (Vascutek) 30, Low Profile (Cook) 4, Zenith (Cook) 28, Endurant (Medtronic) 1, Aneurx (Medtronic) 2, Excluder (WL Gore & Associates) 8, Powerlink (Edwards) 2. Aneurysm diameter: not reported. Setting: academic hospital.
Participants	73 men; age (mean ± SD): 76.3 ± 9.2 years. Comorbidities: diabetes (n = 18), dyslipidaemia (n = 67), BMI ≥ 30 kg/m2 (n = 15), renal insufficiency (n = 24), supra‐aortic trunks lesions (n = 19), angina (n = 42), ASA score III‐IV (n = 56). Geography: France.
Study design	Retrospective cross‐sectional study; participants consecutively enrolled.
Target condition and reference standard(s)	Target condition: endoleak. Definition of endoleak: not reported. Endoleak (absolute n): 14. Prevalence of endoleak: 29.2% (14/48). Reference standard: CTA. Image acquisition: volumetric calculation by CTA carried out by data processing of native sections of CTA; native sections analysed by the free computer software OsiriX. Type of CT scanner: Siemens Medical Solutions Inc (Somatom Definition AS+, Malvern). Use of contrast: "The protocol of imagery included an injection of 100 mL of iodised contrast of 250 concentration, with a 5 mL/s flow IV in the upper limb right." Operators: vascular surgeon.
Index and comparator tests	Index test: 3D US Image production: "The examination was carried out by 1 of the 3 vascular sonographers of our institution with a transperitoneal approach. The ultrasound probe was placed over the umbilicus in the longitudinal axis of the infrarenal abdominal aorta, and side electronic scanning allowed a 3D acquisition of the infrarenal aneurysm to the aortic bifurcation." Type of US: Toshiba Aplio XG ultrasound system (Toshiba Medical Systems, Zoetermeer, the Netherlands) equipped with a marketed 3D 3.5‐MHz dedicated probe. Use of contrast: no. Operator: 1 vascular sonographer.
Follow‐up	No loss to follow‐up, missing data, or adverse events.
Notes	Study aimed to assess if US measurement of volume of aneurysmal sac was comparable with that obtained by CTA (gold standard). Interobserver reproducibility during follow‐up of AAAs after EVAR also investigated. Study conducted between January 2010 and December 2012. "The subgroup analysis on 48 patients that had at least 2 volumetric echography performed during their follow‐up made it possible to highlight a threshold of increase in volume of 6.5 cm3 to suspect an endoleak. This cutoff value of 6.5 cm3 allowed the diagnosis with sensitivity, specificity, predictive positive value, and predictive negative values of 85.7%, 85.3%; 71% and 94%; respectively. The area under the curve was 0.854 (95% CI [0.793‐0.915]."
Table of Methodological Quality
Item	Authors' judgement	Description
Representative spectrum? All tests	Yes	Patients were consecutively enrolled
Acceptable reference standard? All tests	Yes	The reference standard was CTA
Acceptable delay between tests? All tests	No	The average time interval between the achievements of CTA and 3DU for a given patient was 48.18 ± 36.52 days
Partial verification avoided? All tests	Yes	It appears that all patients that received both tests
Differential verification avoided? All tests	Yes	All patients who received the index test were subjected to the same reference standard
Incorporation avoided? All tests	Yes	The index test is not part of the reference standard
Reference standard results blinded? All tests	Yes	“Volumetric calculation by CTA was carried out by a single person, vascular surgeon of formation, by data processing of the native sections of the CTA (Siemens Medical Solutions Inc., Somatom Definition AS+, Malvern). He did not know the results of ultrasound measurements of volume”
Index test results blinded? All tests	Unclear	No description was reported
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