Short summary

Abdominal aortic aneurysms are treated in two ways, either operatively, a method used since 1951, or endovascular, a method used since 1991.

Since the implementation of endovascular abdominal aortic aneurysm repair (EVAR), this procedure has become more widespread, since it is less invasive, has less peri-operative mortality and morbidity as well as shorter postoperative hospital stay.
The major drawback of EVAR is a need for lifelong follow-up usually with contrasts enhanced Computed Tomographic Angiography (CTA), which leads to x-ray exposure and risk for contrast-induced nephropathy as well as the socioeconomic costs. Therefore it is attractive to find alternative diagnostic modalities that does not use radiation, is not nephrotoxic and is cheaper. Contrast enhanced ultrasound is one of the promising modality. The aim of this study is to evaluate if contrast enhanced ultrasound (CEUS)  is a good useable modality and can replace CTA as primary follow up investigation modality for patients that EVAR.

Rationale

EVAR is widely used treatment of AAA. The majorities of patients are older and have renal impairment and long-life surveillance with CTA can further damage renal function. X ray exposure has cumulative effect and rarely can induct carcinoma but is not without danger. Doppler ultrasound and CEUS are alternative modality and is growing evidence that is useful. The contemporary surveillance after EVAR goes into direction that surveillance could be individualized instead of general surveillance program.  The aim of this study is to evaluate if contrast enhanced ultrasound is a good and effective  useable modality and can replace CTA as primary follow up investigation modality for patients that underwent EVAR.

Description of the cohort

The study is retrospective and will include 91 patients who underwent EVAR at Odense University Hospital during Oct 2011-Dec 2014. All these patients at least once were controlled with CEUS during follow-up to diagnose endoleaks and measure maximal diameter of the aneurysm. In the cases of no endoleaks or in a case of endoleak type 2 but unchanged AAA diameter, the patients were controlled with CEUS every year. In the cases of endoleak type 1 or 3 or unclear cases, further diagnosis was made either with CTA or angiography.  The study will analyze how many patients were controlled only by CEUS and how many patients were sent to other diagnostic control. It will be analyzed specificity and sensitivity of CEUS in endoelak detection and endoleak characterisation as well.

Collaborating researchers and departments

Department of Radiology, Thorax- and Angiography section, Odense University Hospital

• Consultant Radiologist and Senior physician Stevo Duvnjak, MD

Department of Radiology, Odense University Hospital, Svendborg

• Specialist Registrar Zaid Al-Dakhiel

Department of Radiology, AAbenraa Hospital

• Specialist Registrar Atatri