Heilberger 1997.

Clinical features and settings	People with aortic aneurysm who received EVAR. Indications for stent‐graft placement were symptomatic thoracic aortic aneurysm in 2 participants, suprarenal AAA in 1 participant, and infrarenal AAAs in remaining 110 participants. Types of endografts used: 9 tube and 34 bifurcate stent‐grafts; Chuter device, Stentor (MinTec, Freeport, Grand Bahama), and EGS aortic endograft (Endovascular Technologies, Menlo Park, CA, USA). Aneurysm diameter: mean: 45.5 mm; range: 32‐72 mm. Setting: department of vascular surgery, Klinikum Nurnberg.
Participants	113 participants; 108 men; mean age: 67.3 years; range: 40‐83 years. Comorbidities: not reported. Geography: Germany.
Study design	Not clear description. Apparently participants were retrospectively identified.
Target condition and reference standard(s)	Target condition: endoleak. Definition of endoleak: persistent blood flow within the aneurysm sac. Primary endoleaks defined as those noted during or immediately after procedure, whereas secondary leaks were detected at follow‐up examinations. Endoleaks that were disclosed only with contrast‐assisted contrast duplex sonography were deemed minor leaks; major endoleaks were those whose flow was detected by routine CDUS. Endoleak (absolute n): 28. Prevalence of endoleak: 24.8% (28/113). Reference standard: helical CT. Image acquisition: "the aorta and iliac arteries were imaged from the celiac trunk to the common femoral arteries using the following parameters: a collimation of 5 mm with a pitch of 1.2, 120 kV, and 240 mA. Fifteen seconds after the end of the arterial phase acquisition, a delayed acquisition was performed using the same parameters as the arterial phase and covering the stented volume. All the images were reconstructed with a 4‐mm increment. A leak was considered present if contrast material was noted outside the stent‐graft in either acquisition." Type of CT scanner: Somatom Plus S or a 4A scanner (Siemens Medical Systems, Erlangen, Germany). Use of contrast: "Either a bolus test injection of 15 mL of contrast medium or a bolus tracking system with a threshold of 100 H was used to determine the optimal start delay (unenhanced CT scans not obtained)."
Index and comparator tests	Index test: CDUS. Image production: 4‐6 standard transverse images of aneurysm sac and stent graft to define their positions. Bifurcated stent‐grafts also examined using pulse Doppler frequency analysis to evaluate flow characteristics in both stent‐graft limbs. Type of US: unclear/not reported. Use of contrast: yes, Levovist: 99.9% of D‐galactose and 0.1% of palmitic acid. Operator: unclear.
Follow‐up	Excluded from follow‐up were: 11 participants (9.7%) who required conversion to open surgical repair either during or shortly after endovascular procedure. Included in this number was 1 participant who died from haemorrhagic shock secondary to a retroperitoneal haematoma at the femoral puncture site; 5 participants died of causes unrelated to procedure: 1 prostate cancer, 1 bronchial carcinoma, and 3 cardiopulmonary disease. Mean follow‐up time: 7.2 months; range: 1‐24 months.
Notes
Table of Methodological Quality
Item	Authors' judgement	Description
Representative spectrum? All tests	Yes	Participants represented average patients who after receiving EVAR are exposed to endoleak surveillance.
Acceptable reference standard? All tests	Unclear	CT scan test with contrast agents performed, but not reported that images evaluated by a radiologist.
Acceptable delay between tests? All tests	Yes	"Computed tomography angiography was performed on the same day."
Partial verification avoided? All tests	Yes	All study participants accounted for and results of reference standard reported for all.
Differential verification avoided? All tests	Yes	All participants who received index test subjected to same reference standard.
Incorporation avoided? All tests	Yes	Index test not part of reference standard.
Reference standard results blinded? All tests	Unclear	Unclear.
Index test results blinded? All tests	Unclear	Unclear.
Relevant clinical information? All tests	Yes	Yes.
Uninterpretable results reported? All tests	Yes	"Among 5 endoleaks due to retrograde side‐branch perfusion, 3 were detected only with contrast‐enhanced duplex scanning; iliac artery occlusion was also documented using duplex, however, 2 stent fractures could not be seen with ultrasound…" "One endoleak originating from the distal iliac limb anchoring site was missed by duplex owing to bowel gas." "Two patients with retrograde aneurysm perfusion via the lumbar arteries remain under observation. In one, a minor leak was documented by duplex with Levovist only; it was not seen on CT scans, even with fractionated injection of contrast agent."
Withdrawals explained? All tests	Unclear	Excluded from follow‐up were 11 participants (9.7%) who required conversion to open surgical repair either during or shortly after endovascular procedure. Included in this number was 1 participant who died from haemorrhagic shock secondary to a retroperitoneal haematoma at the femoral puncture site. 5 participants died during follow‐up of causes unrelated to the procedure: 1 prostate cancer, 1 bronchial carcinoma, and 3 cardiopulmonary disease.