To Determine the Frequency of Concordance Between Duplex Ultrasound Scan and Ct Scan in Detection of Endo-leak in Patients Following EVAR

Abstract

Objective: To determine the frequency of concordance between Duplex ultrasound scan and
CT scan in detection of endo-leak in patients following EVAR.
Methods: This retrospective, descriptive study was conducted at Department of Vascular
Surgery, Mater Misericordiae University Hospital Dublin, Ireland. The study was conducted
from14thJuly, 2014 to13th July, 2016. Age range 50-70 years were included in the study. All
patients who had Endovascular Aneurysm repair (EVAR) were followed up in six months' time
using Duplex ultrasound scan and Computerized Tomography (CT). The detection of endo-leak
on Duplex ultrasound scan and confirmed by Computerized Tomography (CT).The concordance
between the two investigations was estimated by calculating the overall percentage of agreement
(concordance) and the κ coefficient. The follow up imaging results were collected by using PACS
(Picture archiving and communication system). All the data entered and analyzed using computer
software SPSS version 17. Mean and standard deviation was calculated for quantitative variables
like Age and BMI. Frequency and percentages were calculated for qualitative variables like
gender, co morbidities like hypertension, DM, smoking status and concordance. Effect modifiers
gender, BMI and co morbidities DM and HTN were controlled by stratification of data.
Results: Total 113 patients were enrolled in this study. In the study, mean age was 68yeatrs with
the standard deviation of 3.09. 70.8% of patients were males and 29.2% were females. 46.9% of
patients had BMI of 26-30 BMI and 34.5% had BMI >30. Among the total patients, 64.6% patients
were diabetic, 77% hypertensive and 88.5% patients were smokers. 70.8% of endo-leaks were
diagnosed by Duplex ultra-sound scan, while 77.8% of endo-leaks were diagnosed by CT scan.
Cohens kappa value is 0.91 which shows strong association. Concordance between Duplex
ultra-sound scan and CT scan calculated as 95.6%.
Conclusions: This study concluded that Duplex ultra-sound scan can safely replace CT scan
as a surveillance modality. Duplex ultra-sound scan can be used as a primary long-term
surveillance imaging modality for patients with post EVAR and it will be more economical for
patients without any loss of scan accuracy.