Sensitivity and Specificity of Ultrasonographic Compared with CT Angiography in Detecting Femoropopliteal and Infrapopliteal Arterial Lesions in Lower Extremity Arterial Disease in Dr.

Background: Peripheral artery disease (PAD) is a chronic occlusive arterial disease of the extremities caused by atherosclerosis. 1 It is estimated that 20-30% of the population worldwide suffered PAD. 2 PAD is associated with a 1-year mortality and limb loss rate of 20%. 7 Critical limb ischemia (CLI) is a late stage clinical presentation of PAD. Imaging of the entire artery is possible using CT angiography. However, CT angiography has its drawbacks because the contrast used can be nephrotoxic, the risk of allergies, expensive, and not all health services have it. Ultrasonographic’s (USG) sensitivity, specificity and accuracy were 96.55%, 61.53%, and 78.84% for detecting lower limb distal artery lesions. 11 Ultrasonographic does not require the use of contrast, radiation, low cost and almost all health services have them. 12 However, the Ultrasonographic examination has its limitations depending on the operator's capabilities. It is therefore necessary to conduct research that have never been previously studied in South Sumatra. Methods: This study is a diagnostic test study that examines the sensitivity and specificity of ultrasound in detecting LEAD artery lesions. The samples were Results: At the femoropopliteal level, the results obtained were 91% sensitivity and 86% specificity. At the infrapopliteal level, the results obtained were 95% sensitivity and 87% specificity. Conclusion: Ultrasonographic has high sensitivity and specificity in detecting LEAD’s lesions

and CT angiography scanning provides higher spatial resolution and coverage over 120cm. 10 Imaging the entire artery is possible using CT angiography and has found excellent compatibility with digital subtraction angiography (DSA). However, CT angiography has its drawbacks because the contrast used can be nephrotoxic, the risk of allergies is expensive, and not all health services have it. Ultrasound (USG) is a good method for screening and follow-up, as well as for the definitive diagnosis of peripheral artery disease.
The sensitivity, specificity and accuracy of ultrasound were 96.55%, 61.53%, and 78.84% for detecting lower limb distal artery lesions. 11 Ultrasound is a noninvasive technique that does not require the use of contrast, preparation of the patient before examination, or radiation exposure, low cost and nearly all services health has it. 12 However, ultrasound examination has limitations that is dependent on the ability of the operator.
Several studies on the comparison between ultrasound and CT angiography in detecting lower extremity arterial disease (LEAD) lesions, Ahmed I. Gamal El Dein et al. 62 stated that there was a significant and accurate relationship between ultrasound and CT angiography with the kappa technique. At the level of the common femoral artery, superficial femoral artery, popliteal artery, peroneal artery and anterior tibial artery, the kappa test values were 0.88, 0.82, 0.87, 0.88 and 0.88. In the study of Chidambaram et al. 11 , it was obtained a sensitivity of 89%, specificity of 93%, and accuracy of 92%.
CT angiography has limitations on nephrotoxic contrast agents, cannot be performed on patients with renal dysfunction, is expensive, risks allergies, and not all health services have it. While USG is a sensitive, non-invasive, inexpensive, non-toxic examination to detect LEAD lesions, but ultrasonography is an operator dependent examination. Therefore, it is deemed necessary to conduct research on the sensitivity and specificity of ultrasonography compared to CT angiography in detecting lesions in LEAD which have not been previously studied in South Sumatra.

Methods
This study is a diagnostic test study that examines the sensitivity and speci ficity of ultrasound in detecting LEAD artery lesions compared to CT angiography.
The population was LEAD patients who came to the FK UNSRI / RSMH Vascular and Endovascular Surgery Division. The sample in this study was the entire population that met the inclusion criteria.
The inclusion criteria of this study were LEAD patients who were included in the indication for CT angiography examination and the exclusion criteria were patients who had major amputation 53 prior to CT angiography, patients with impaired kidney function, a history of allergy to contrast substances and pregnant women.
The sample size in this study was 25 people. The variables of this study included gender, age, history of diabetes mellitus, history of hypertension, hyperlipidemia, length of the lesion, location of the lesion, and type of lesion.
The sample data is presented in 2x2 table form and divided into 2 levels, namely femoropoplitea and infrapoplitea.

Demographic characteristics
There were 29 PAD patients who came to RSMH who were willing to participate in the study.
Distribution of samples based on gender, age, DM and hypertension were show in table 1.

Laboratory characteristics
The LDL test results was show in table 1.

CT angiography characteristics
In this study, distribution femoropopliteal and infrapopliteal lesions based on CT angiography and USG were show in table 1.   In the United States, cases of PAD who are more than 60 years old have a greater percentage of those who are less than 60 years old. In line with the research results of Schroll et al, who reported that PAD sufferers were mostly found in respondents who were over 60 years of age. 54 According to Criqui et al.
national health and nutrition examination study), aged over 65 years have a higher risk of PAD. 4 The results of this study are consistent with research by Schroll which shows that diabetes mellitus is a risk factor for the occurrence. 54 This is in line with the results of the study by Ness et al which stated that diabetes mellitus is a predisposing factor. 55 The results of this study are in accordance with the Edinburgh Artery Study, where the prevalence of patients increases. in people with diabetes and poor blood sugar tolerance (20.6%) compared with people with good blood sugar tolerance (12.5%). 56 The results of this study are in accordance with research by Schroll which shows that hypertension is a risk factor for this disease. 54 This is in line with the results of the research of Ness et al which stated that hypertension is a modifiable risk factors. 19 Approximately 50% -92% of sufferers also suffer from hypertension. 24 The risk of claudication increases 2.5-4 times in hypertension patients. 20 The results of this study are inconsistent with the study by Schroll which showed that hyperlipidemia was a risk factor. 54 This is in line with the results of the study by Ness et al which stated that hyperlipidemia is a predisposing factor. 55 Hyperlipidemia increases the incidence of PAD by 10% for every 10 mg / dl increase of total cholesterol. 57 Hyperlipidemia is one of the causes of endothelial dysfunction and increases the production of oxygen free radicals which deactivate nitric oxide, so that LDL-C will accumulate in the intima layer where endothelial permeability increases.
The accumulation of LDL-C in the vascular wall in the intima layer coupled with the chemical changes of fat triggered by free radicals in the artery wall will produce oxidized LDL-C which plays a role and accelerates the formation of atheromatous plaque. 58,59 Growth factors and growth hormones stimulate the proliferation and migration of macrophages and vascular smooth muscle cells to form atherosclerotic plaques. Proliferation of smooth muscle cells and deposition of extra-cell matrix in the intima converts fatty patches to mature fibrofatty atheromas and plays a role in causing the growth of atherosclerotic lesions and forming atherosclerotic plaques. 59,60 This causes a macroangiopathic process in the blood vessels so that the circulation of the tissue occurs. 60 Based on the location of the lesions, a study conducted by Ahmed I. Gamal El Dein et al 62  In a study conducted by Chidambaram et al. 11 , it was found that the sensitivity was 89%, specificity was 93%, and accuracy was 92%. In accordance with the research conducted by Ahmed I. Gamal El Dein et al. 62 , who stated that there was a significant and accurate relationship using CT angiography and ultrasound with the kappa technique. At the level of the common femoral artery, the kappa test value is 0.88. At the level of the superficial femoral artery, the kappa test value was 0.82. In the popliteal artery, the kappa test value was 0.87. The results of this study are in accordance with A. Ali et al., 63 who stated that the sensitivity of Doppler ultrasound was 90.46%, the specificity was 92.05%, and the accuracy was 91.81% compared to CT angiography.
In a study conducted by Chidambaram et al. 11 , it was found that the sensitivity was 96%, specificity was 62%, and accuracy was 79%. In accordance with the research conducted by Ahmed I. Gamal El Dein et al. 62 , who stated that there was a significant and accurate relationship using CT angiography and Doppler ultrasound with the kappa technique. In the peroneal artery, the kappa test value is 0.88. In the anterior tibial artery, the kappa test value was 0.88. The results of this study are in accordance with A. Ali et al., 63