How to recognize stent graft infection after endovascular aortic repair: the utility of 18F-FDG PET/CT in an infrequent but serious clinical setting.

OBJECTIVE: To evaluate the diagnostic performance of 18F-FDG PET/CT in the detection of stent graft infection (SGI). METHODS: In a retrospective study, two nuclear medicine physicians have independently analyzed 17 18F-FDG PET/CT examinations performed for clinical suspicion of SGI. The images were evaluated for the uptake pattern and intensity, and by the maximum standard uptake value (SUVmax), the target-to-background ratio with blood pool (TBRBP) and liver uptake (TBRhep) as a reference. The SGI was defined as the presence of focal hyperactivity with an intensity exceeding hepatic uptake. CT images were independently assessed for signs of SGI. Clinical review of all further patients' data served as the standard of reference. RESULTS: Nine cases were established as SGI by the clinical review. PET/CT correctly diagnosed SGI in eight and yielded a sensitivity of 89% and specificity of 100%. The mean SUVmax, TBRBP, and TBRhep values were 9.8 ± 4.0, 6.9 ± 2.6, and 4.6 ± 1.7 in the group of patients with true SGI, and 4.0 ± 1.1, 2.5 ± 0.4 (p < 0.001) and 1.9 ± 0.2 (p < 0.001) in true negative cases, respectively. CT alone showed a sensitivity of 78% and specificity of 100% and was concordant with PET/CT in 14 cases. The best performing threshold values of SUVmax, TBRBP, and TBRhep were 5.6, 3.5, and 2.2, respectively. CONCLUSION: 18F-FDG PET/CT with expert evaluation, semiquantitative and quantitative image analysis with the proposed threshold values for SUVmax, TBRBP, and TBRhep has good diagnostic accuracy in the detection of SGI. We propose that visual grading scale for SGI should use hepatic uptake as a visual reference.

Percutaneous Mechanical Thrombectomy Using Rotarex® S Device in Acute Limb Ischemia in Infrainguinal Occlusions.

PURPOSE: To evaluate the effectiveness of percutaneous mechanical thrombectomy using Rotarex S in the treatment of acute limb ischemia (ALI) in infrainguinal occlusions in a retrospective study of patients treated in our institution. METHODS: In this study, we identified a total of 147 ALI patients that underwent mechanical thrombectomy using Rotarex S at our institution. In 82% of the cases, percutaneous thrombectomy was used as first-line treatment, and for the remainder of the cases, it was used as bailout after ineffective aspiration or thrombolysis. Additional fibrinolysis and adjunctive aspirational thrombectomy were utilized for outflow occlusion when required. Procedural outcomes, amputation rate, and mortality at 30 days were evaluated. RESULTS: Of the 147 patients treated with mechanical thrombectomy, Rotarex S was used as first-line treatment in 120 cases and as second-line treatment in 27 cases. Overall, we achieved 90.5% procedural revascularization success rate when combining mechanical thrombectomy with limited thrombolysis for severe outflow obstruction, and 1 death and 3 amputations were observed. We achieved primary success in 68.7% of the patients with the mechanical thrombectomy only, and in 21.8% of the patients, we successfully used additional limited thrombolysis in the outflow. The overall mortality was 0.7% and amputation rate was 2% at 30 days. CONCLUSION: Percutaneous mechanical thrombectomy as first-line mini-invasive treatment in infrainguinal ALI is safe, quick, and effective, and the performance outcomes can be superior to that of traditional surgical embolectomy.

[A rare case of mobile atherosclerotic plaque with a high embolic potential in the femoral artery]. / Vzácný prípad mobilního aterosklerotického plátu ve femorální tepne s vysokým embolizacním potenciálem.

Atherosclerosis is a diffuse disease which may lead to the development of unstable atherosclerotic plaque. Its rupture can result in acute ischemic event. The atherosclerotic plaques with a mobile component are typical presentations of such instability and patients with these plaques are at high risk of acute ischemic events. In the current literature, substantial data regarding the mobile atherosclerotic plaques in carotid arteries and thoracic aorta is published. However there are almost no data concerning the mobile plaques in the peripheral arteries of the lower limbs. We present a rare case of a patient with generalized atherosclerosis, in whom an asymptomatic mobile atherosclerotic plaque in the common femoral artery with a high embolic potential was diagnosed. This plaque was successfully removed by femoral endarterectomy. On the basis of this case, we review the possibilities and limitations of the current imaging methods in detection of mobile plaques in the peripheral arteries. Moreover optimal therapeutic approaches in such patients are discussed.

Acute Digital Ischemia Associated with Closed Injury.

Injury of an artery has a significantly worse prognosis for the patient than a venous injury. Blunt injuries of lower limb digital arteries with the development of acute ischemia present a very rare phenomenon. A crush mechanism with a defect of the non-wetted surface of vessel's inner part and the development of subsequent thromboischemic lesion is essential for the development of ischemia. We report a blunt injury of the right lower limb in a patient after incorrect stepping with subsequent lesion of digital arteries and the development of acute acral ischemia of the right toes.

[Deep calf vein thrombosis]. / Flebotrombóza lýtkových zil.

Isolated calf vein thrombosis in the population of patients with deep vein thrombosis is found approximately in 10 to 25 % of cases. We present 3 cases of calf vein thrombosis which occurred due to unusual causes. Specific characteristics of this form of thromboembolic disease are discussed and compared to proximal deep vein thrombosis with emphasis to symptoms, risk of complications, prognosis and therapeutic approach.

[Carotid plaque exulcerated]. / Exulcerovaný karotický plát.

The authors report a case of a 77 years old male patient with mild stenosis of the carotid artery caused by an exulcerated plaque in the carotid bifurcation. The patient presented with recurrent ipsilateral strokes which were treated with intravenous thrombolysis. A brief review of the literature related to the management of unstable exulcerated carotid plaque is presented in this article with emphasis on current treatment options. Carotid endarterectomy if often performed in such cases. However, the outcome of the procedure remains still very controversial. In the described case, conservative approach using optimal medical treatment with lipid lowering agents, antiplatelet and antihypertensive therapy was chosen mainly because of patient preference and resulted in favourable outcome.

Magnetic resonance angiography, digital subtraction angiography and Doppler ultrasonography in detection of carotid artery stenosis: a comparison with findings from histological specimens.

BACKGROUND: Patients' life expectancy, clinical symptomatology and the extent of carotid stenosis are the most important factors when deciding whether to perform carotid endarterectomy (CEA) in patients with carotid stenosis. Therefore, the accuracy of measuring carotid stenosis is of utmost importance. METHODS: Patients with internal carotid artery (ICA) stenosis were investigated by digital subtraction angiography (DSA), Doppler ultrasonography (DUS) and magnetic resonance angiography (MRA). Atherosclerotic plaque specimens were transversally cut into smaller segments and histologically processed. The slides were scanned and specimens showing maximal stenosis were determined; the minimal diameter and the diameter of the whole plaque were measured. DSA, DUS and MRA measurements were obtained in 103 patients. A comparison between preoperative and histological findings was performed. In addition, correlation coefficients were computed and tested. RESULTS: Results show a significant correlation for each of the diagnostic procedures. Mean differences in the whole cohort between preoperative measurements and the histological measurements are as follows: angiographic measurement of carotid stenosis underestimated histological measurement by 14.5% and MRA by 0.7%, but DUS overestimated by 6.6%. The results in severe stenosis (> or =70%) are as follows: angiographic measurement underestimated the histological measurements by 2.3%, but MRA overestimated by 12.1% and DUS by 11.3%. The results in moderate stenosis (50-69%): angiographic measurement underestimated the histological measurements by 12.3%, but MRA overestimated by 0.2% and DUS by 7.2%. The results in mild stenosis (30-49%): angiographic measurement underestimated the histological measurements by 24.7% and MRA by 7.6%, but DUS overestimated by 3.3%. CONCLUSIONS: Our study confirms that DSA underestimates moderate and mild ICA stenosis. DUS slightly overestimated moderate ICA stenosis and highly overestimated high-grade ICA stenosis. MRA proved to be accurate in detecting moderate ICA stenosis, but slightly underestimated mild stenosis and overestimated high-grade stenosis. The surgeon should be aware of these discrepancies when deciding whether to perform CEA in patients with ICA stenosis.