ABSTRACT
BACKGROUND: Current techniques to evaluate computed tomography (CT) foot perfusion in patients with critical limb ischemia use high contrast doses and cannot be used during endovascular procedures. CT perfusion of the foot with intra-arterial contrast injection during endovascular treatment in a hybrid angiography CT suite might solve these problems. PURPOSE: The main objective of this study was to evaluate whether intra-arterial CT foot perfusion using a hybrid CT angiosystem is feasible during endovascular treatment for critical limb ischemia. MATERIAL AND METHODS: This prospective pilot study investigated intraprocedural, intra-arterial CT perfusion of the foot using a hybrid CT angiosystem in 12 patients before and after endovascular treatment for critical limb ischemia. Time to peak (TTP) and arterial blood flow were measured before and after treatment and compared using a paired t test. RESULTS: All 24 CT perfusion maps could be calculated adequately. The contrast volume used for one perfusion CT scan was 4.8 ml. The mean TTP before treatment was 12.8 seconds (standard deviation [SD] 2.8) and the mean TTP posttreatment was 8.4 seconds (SD 1.7), this difference being statistically significant (p=.001). Tendency toward increased blood flow after treatment, 340 ml/min/100 ml (SD 174) vs 514 ml/min/100 ml (SD 366) was noticed (p=.104). The mean effective radiation dose was 0.145 mSv per scan. CONCLUSION: Computed tomography perfusion of the foot with low contrast dose intra-arterial contrast injection during endovascular treatment in a hybrid angiography CT suite is a feasible technique. CLINICAL IMPACT: Intra-arterial CT foot perfusion using a hybrid CT-angiography system is a feasible new technique during endovascular therapy for critical limb ischemia to assess the results of the treament. Future research is necessary in defining endpoints of endovascular treatment and establishing its role in limb salvage prognostication.
ABSTRACT
INTRODUCTION@#Image-guided thermal ablation, preferably with ultrasonography (US), is increasingly used for treatment of small liver tumours. Perfluorobutane-contrast-enhanced US (pCEUS) is a promising tool that may allow for targeting of tumours that are otherwise imperceptible on greyscale US. Although pCEUS has been reported to be effective, the literature has been limited outside of Japan and South Korea. We aimed to provide data that supports the use of pCEUS in the thermal ablation of sonographically occult liver tumours.@*METHODS@#We conducted a retrospective single-centre study of 35 consecutive patients who underwent pCEUS-guided ablation of 48 liver tumours with a median size of 1.2 cm. Periprocedural, one-month post-treatment and relevant follow-up imaging studies were reviewed. Electronic records were also obtained, with long-term follow-up data of 12-28 months being available for 32 patients.@*RESULTS@#36 (75%) tumours that were imperceptible on greyscale US became visible with pCEUS. Overall, complete tumour ablation at one month was 89%. 1 (3%) patient developed a major complication following treatment, while 6 (17%) had minor post-treatment complaints. The local tumour progression rate was 17%, with a median time of 14 months.@*CONCLUSION@#pCEUS has a role in US-guided thermal ablation of liver tumours, offering a high technical success rate that is comparable to reported data. Additional benefits may include improved procedural time and freedom from ionising radiation.
