Manifestation And Clinical Significance Of64-slice Spiral CT Angiography By Test-bolus In Peripheral Arterial Occlusive Disease

Objective:To1) determine the superiority of64-slice spiral CT Angiography (CTA) by test-bolus in Peripheral arterial occlusive disease (PAOD);2) discuss the diagnostic value of CTA in various kinds of PAOD;3) investigate the association between CTA value and clinical symptom in various kinds of diseases.Methods:Sixty-one suspected patients with Peripheral arterial occlusive disease were enrolled in this study, and randomly divided into two study groups including38subjects underwent CTA by bolus-tracking (group I) and26subjects underwent CTA by Test-bolus (group II). For the test-bolus technique a small volume of contrast15ml is injected, then according to abdominal aorta and bilateral anterior tibial artery or the posterior tibial artery (ankle level) dynamic scanning time to peak to determine the CTA scan delay point and scan duration. The CTA value was determined based on4parameters, such as Abdominal aorta under paragraph to paragraph iliac artery, Femoral and popliteal artery, Leg artery segment and Foot artery segment, respectively. Finally, compared the quality of images based on CT value in both groups. Patients can be divided into3major categories (1) diabetic and non-diabetic group;(2) hypertensive and non-hypertensive group;(3) diabetes mellitus alone, hypertension alone, diabetes mellitus combined with hypertension group and without diabetes mellitus or hypertension group. Clinical manifestations can be divided into four levels:level I) no pain; level Ⅱ) intermittent claudication; level Ⅲ) rest pain; level IV) combine the cutaneous gangrene.Results:As shown by small dose of contrast agent pre-test, under the abdominal a orta level (L3/4level), the average peak time is (26.54±7.39) s and the image qu ality of contrast agent pre-test is100%; In ankle level (anterior tibial artery or post erior tibial artery), the average peak time is (46.76±10.07) s and the image quality of contrast agent pre-test is100%. The quality of CTA image below the knee joint (Leg artery segment and Foot artery segment) was significantly higher in group II compared with groups I (P<0.05). The stenotic level of4segment was significan tly higher in diabetes mellitus group compared with non-diabetes mellitus group (P <0.05); The level of lower abdominal aorta-iliac arteries segment, Femoral and po pliteal artery segment and Leg artery segment was significantly higher in hypertensi on group compared with non-hypertension group (P<0.01). The statistical significa nce was found by the analysis artery stenotic level based on4segment in each group, including diabetes mellitus group, hypertension group, diabetes mellitus combine d with hypertension group and normal group,(P<0.05). The statistical significance f ound by analysis of relationship between clinical classification and artery stenotic level i n femoral and popliteal artery segment, leg artery segment and footartery segment (P<0.05). The stenotic level was significantly higher in diabetes mellitus combined hypert ension group compared with diabetes mellitus group (P<0.05). The stenotic level was significantly higher in diabetes mellitus combined hypertension group compared with h ypertension group (P<0.05). Clinical classificationand lower extremity artery stenosis1evel were positively correlated (P<0.01). Theoccurrence of lower limb artery stenosis i n patients with diabetes mellitus was significantly associated with foot arteries (P<0.05), and the occurrence of lower limb artery stenosis in patients with hypertension was significantly associated with abdominal aorta under paragraph to paragraph iliac artery, femoral-popliteal artery and Leg artery segment (P<0.05)Conclusion:The method of Test-bolus can get high quality image of CTA compared with bolus-tracking, which may provide a potential therapeutic strategy for clinical diagnosis and treatment of PAOD. Clinical symptoms of PAOD are associate with an increase of incidence and level of bilateral leg artery stenosis. Finally, the pathological changes of PAOD is majorly involved in small blood vessels in patient with diabetes mellitus and is majorly involved in larger blood vessels in patient with hypertension.