How to combine CTA, 99mTc-WBC SPECT/CT, and [18F]FDG PET/CT in patients with suspected abdominal vascular endograft infections?

PURPOSE: We aimed at comparing 99mTc-HMPAO white blood cells (99mTc-WBC) scintigraphy, 18fluorine-fluorodeoxyglucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) and CT angiography (CTA) in patients with suspected abdominal vascular graft or endograft infection (VGEI). Moreover, we attempted to define a new visual score for interpreting [18F]FDG PET/CT scans aiming at increasing its specificity. METHODS: We prospectively compared 99mTc-WBC SPECT/CT, [18F]FDG PET/CT, and CTA in 26 patients with suspected abdominal VGEI. WBC scans were performed and interpreted according to EANM recommendations. [18F]FDG PET/CT studies were assessed with both qualitative (Sah's scale and new visual score) and semi-quantitative analyses. CTA images were interpreted according to MAGIC criteria. Microbiology, histopathology or a clinical follow-up of at least 24 months were used to achieve final diagnosis. RESULTS: Eleven out of 26 patients were infected. [18F]FDG PET/CT showed 100% sensitivity and NPV, with both scoring systems, thus representing an efficient tool to rule out the infection. The use of a more detailed scoring system provided statistically higher specificity compared to the previous Sah's scale (p = 0.049). 99mTc-WBC SPECT/CT provided statistically higher specificity and PPV than [18F]FDG PET/CT, regardless the interpretation criteria used and it can be, therefore, used in early post-surgical phases or to confirm or rule out a PET/CT finding. CONCLUSIONS: After CTA, patients with suspected late VGEI should perform a [18F]FDG PET/CT given its high sensitivity and NPV. However, given its lower specificity, positive results should be confirmed with 99mTc-WBC scintigraphy. The use of a more detailed scoring system reduces the number of 99mTc-WBC scans needed after [18F]FDG PET/CT. Nevertheless, in suspected infections within 4 months from surgery, 99mTc-WBC SPECT/CT should be performed as second exam, due to its high accuracy in differentiating sterile inflammation from infection.

[18F]FDG Uptake in Non-Infected Endovascular Grafts: A Retrospective Study.

Purpose: After endovascular aneurysm repair (EVAR), an increased [18F]FDG uptake may be observed at PET/CT, being common to both vascular graft/endograft infection (VGEI) and sterile post-surgical inflammation. Increased non-specific metabolic activity, due to foreign body reaction, can persist for several years after surgery, thus complicating the interpretation of PET/CT studies. In this paper, we aimed to assess [18F]FDG distribution at different time-points after the implant of abdominal Endurant® endografts in patients without suspicion of infection. Methods: We retrospectively evaluated [18F]FDG/CT in 16 oncological patients who underwent abdominal aortic aneurysm exclusion with Endurant® grafts. Patients had no clinical suspicion of infection and were followed up for at least 24 months after scan. [18F]FDG PET/CT scans were interpreted using both visual and semi-quantitative analyses. Results: The time between the EVAR procedure and [18F]FDG PET/CT ranged between 1 and 36 months. All grafts showed mild and diffuse [18F]FDG uptake without a focal pattern. Mean values of SUVmax were 2.63 ± 0.48 (95% CI 2.38-2.88); for SUVmean 1.90 ± 0.33 (95% CI 1.72-2.08); for T/B ratios 1.43 ± 0.41 (95% CI 1.21-1.65). SUVmax and SUVmean were not correlated to the time elapsed from the procedure, but we observed a declining trend in T/B ratio over time. Conclusions: Endovascular implant of Endurant® grafts does not cause a significant inflammatory reaction. The evidence of faint and diffuse [18F]FDG uptake along the graft can reliably exclude an infection, even in early post-procedural phases. Therefore, in patients with a low probability of VGEI, [18F]FDG PET/CT can also be performed immediately after EVAR.

Surgical treatment of two post-traumatic pseudoaneurysms of genicular artery.

Pseudoaneurysms of the genicular arteries represent an extremely rare clinical occurrence. Nevertheless, young and athletic subjects, who are frequently exposed to direct joint trauma and subsequent reconstructive orthopedic surgery, are especially prone to developing these lesions. The aim of the present report was to describe two cases of a genicular artery pseudoaneurysm observed in young and healthy athletic male patients and successfully managed by surgical excision.

Is Evar Feasible in Challenging Aortic Neck Anatomies? A Technical Review and Ethical Discussion.

BACKGROUND: Endovascular aneurysm repair (EVAR) has become an accepted alternative to open repair (OR) for the treatment of abdominal aortic aneurysm (AAA) despite "hostile" anatomies that may reduce its effectiveness. Guidelines suggest refraining from EVAR in such circumstances, but in clinical practice, up to 44% of EVAR procedures are performed using stent grafts outside their instruction for use (IFU), with acceptable outcomes. Starting from this "inconsistency" between clinical practice and guidelines, the aim of this contribution is to report the technical results of the use of EVAR in challenging anatomies as well as the ethical aspects to identify the criteria by which the "best interest" of the patient can be set. MATERIALS AND METHODS: A literature review on currently available evidence on standard EVAR using commercially available endografts in patients with hostile aortic neck anatomies was conducted. Medline using the PubMed interface and The Cochrane Library databases were searched from 1 January 2000 to 6 May 2021, considering the following outcomes: technical success; need for additional procedures; conversion to OR; reintervention; migration; the presence of type I endoleaks; AAA-related mortality rate. RESULTS: A total of 52 publications were selected by the investigators for a detailed review. All studies were either prospective or retrospective observational studies reporting the immediate, 30-day, and/or follow-up outcomes of standard EVAR procedures in patients with challenging neck anatomies. No randomized trials were identified. Fourteen different endo-grafts systems were used in the selected studies. A total of 45 studies reported a technical success rate ranging from 93 to 100%, and 42 the need for additional procedures (mean value of 9.04%). Results at 30 days: the incidence rate of type Ia endoleak was reported by 37 studies with a mean value of 2.65%; 31 studies reported a null migration rate and 32 a null conversion rate to OR; in 31 of the 35 studies that reported AAA-related mortality, the incidence was null. Mid-term follow-up: the incidence rate of type Ia endoleak was reported by 48 studies with a mean value of 6.65%; 30 studies reported a null migration rate, 33 a null conversion rate to OR, and 28 of the 45 studies reported that the AAA-related mortality incidence was null. CONCLUSIONS: Based on the present analysis, EVAR appears to be a safe and effective procedure-and therefore recommendable-even in the presence of hostile anatomies, in patients deemed unfit for OR. However, in order to identify and pursue the patient's best interest, particular attention must be paid to the management of the patient's informed consent process, which-in addition to being an essential ethical-legal requirement to legitimize the medical act-ensures that clinical data can be integrated with the patient's personal preferences and background, beyond the therapeutic potential of the proposed procedures and what is generically stated in the guidelines.

Incidence and Fate of Refractory Type II Endoleak after EVAR: A Retrospective Experience of Two High-Volume Italian Centers.

Introduction: The aim of the present study is to report the outcome of patients presenting an isolated type II endoleak (TIIEL) requiring reintervention and to identify clinical and anatomical characteristics potentially implicated in refractory TIIEL occurrence and fate. Materials and Methods: A multicenter retrospective study on TIIEL requiring reintervention was conducted between January 2003 and December 2020. Demographic and clinical characteristics, procedural technical aspects, reinterventions, and outcomes were recorded. TIIEL determining sac expansion greater than 10 mm underwent a further endovascular procedure aiming to exclude aneurismal sac. Redo endovascular procedures were performed via endoleak nidus direct embolization and/or aortic side branches occlusion. TIIELs responsible for persisting aneurysmal sac perfusion 6 months after redo endovascular procedures were classified as "refractory" and submitted to open conversion. Results: A total of 102 TIIEL requiring reintervention were included in the final analysis. Eighty-eight (86.27%) patients were male, the mean age was 77.32 ± 8.08 years, and in 72.55% of cases the American Society of Anaesthesiologists (ASA) class was ≥3. The mean aortic diameter was 64.7 ± 14.02 mm, half of treated patients had a patent inferior mesenteric artery (IMA), and 44.11% ≥ 3 couples of patent lumbar arteries (LA). In 49 cases (48.03%) standard endovascular aneurysm repair (EVAR) procedure was completed without adjunctive maneuvers. All enrolled patients were initially submitted to a further endovascular procedure once TIIEL requiring reintervention was diagnosed; 57 patients underwent LAs or IMA embolization (55.87%), 42 transarterial aneurismal sac embolization (41.17%), and three (2.96%) laparoscopic ostial ligations of the inferior mesenteric artery. During a mean follow-up of 15.22 ± 7.57 months (7−48), a redo endovascular approach was able to ensure complete sac exclusion in 52 cases, while 50 patients presented a still evident refractory TIIEL and therefore a surgical conversion or semiconversion was conducted. At the univariate analysis refractory TIIEL patients were significantly different from those who did not develop the complication in terms of preoperative clinical, morphological characteristics, and initial EVAR procedures: coronary artery disease occurrence (p = 0.005, OR: 3.18, CI95%: 1.3−7.2); preoperative abdominal aortic aneurysm (AAA) sac diameter (p = 0.0055); IMA patency (p = 0.016, OR: 2.64, CI95%: 1.18−5.90); three or more patent LAs; isolated standard EVAR without adjunctive procedures (p > 0.0001; OR: 9.48, CI95%: 3.84−23.4). Conclusions: Our experience seems to demonstrate that it is reasonable to try to preoperatively identify those patients who will develop a refractory TIIEL after EVAR and those with a TIIEL requiring reintervention for whom a simple endovascular redo will not be enough, needing surgical conversion.

Factors Affecting the Outcome of Symptomatic Carotid Stenosis Surgical Treatment in a Single Center Series.

BACKGROUND: The aim of this study is to evaluate the role of preoperative ischemic brain lesion (IBL) volume, assessed by Diffusion-weighted magnetic resonance brain imaging (DW-MRI) with RAPID® processing, and surgery timing in predicting post-operative neurological outcomes in symptomatic carotid stenosis (SCS) patients treated with carotid endarterectomy (CEA). MATERIALS AND METHODS: All patients with SCS who underwent CEA between January 2010 and June 2020 were considered. IBLs ipsilateral to the stenosis were identified in the preoperative magnetic resonance brain (MRI). The volume was quantified in mL and correlated with 30-day rates of stroke and stroke/death by χ2 and receiver operating characteristic (ROC) curve. RESULTS: One hundred thirty-four patients were surgically treated for SCS during the entire study period. CEA procedures were defined as emergent, urgent, or elective if performed within 48 hr, between 48 hr and 14 days, or after 14 days from symptoms onset, respectively. Cumulative new ipsilateral stroke rate was 4,5%, with a statistically higher neurological complications in emergent patients compared to urgent and elective patients (10,6%, 1,47% and 0% respectively, P 0,039). ROC curve analysis showed a volume of 10 mL was predictive of postoperative stroke with 100% sensitivity and 80% specificity. An IBL volume >10 mL was an independent risk factor for postoperative stroke. In fact, the perioperative neurological complication rate was significantly different in high-IBL volume patients (>10 mL) compared with low-IBL volume patients (<10 mL) (P 0,003) CONCLUSIONS: The present study suggests that the optimal timing for CEA is between 48 hr and 14 days. Furthermore, the present study suggests that the presence of the IBL, by itself, is not definitively related with an unsatisfactory neurological outcome. However, an IBL higher than 10 mL should be as a reliable threshold value adverse neurological result in SCS patients.

Neutrophil-to-Lymphocyte Ratio Could Predict Outcome in Patients Presenting with Acute Limb Ischemia.

INTRODUCTION: Acute limb ischemia (ALI), classified according to Rutherford's classification (RC), is a vascular emergency burdened by high rates of mortality and morbidity. The need of new and different prognostic values for ALI has emerged, and, among all, the neutrophil-to-lymphocyte ratio (NLR) has been proven as a strong outcome predictor in vascular disease. The aim of this study is to investigate the role of preoperative NLR in predicting clinical outcomes in patients presenting acute limb ischemia. MATERIAL AND METHODS: A single-center retrospective study was conducted between January 2015 and December 2019. Demographic and clinical characteristics, procedural technical aspects, postoperative and early (up to 30-day) outcomes were recorded. All enrolled patients were categorized into low- and high-NLR at baseline, using a cut-off value of 5. Study outcomes were 30-day all-cause mortality and amputation rates. RESULTS: A total of 177 ALI patients were included in the final analysis (6 RC I, 44 RC IIA, 108 RC IIB, and 19 RC III), 115 males (65%), mean age 78.9 ± 10.4 years. Mean NLR at hospital presentation was 6.65 ± 6.75 (range 0.5-35.4), 108 (61.1%) patients presented a low-NLR, 69 (38.9%) a high-NLR. Immediate technical success was achieved in 90.1% of cases. At 30 days, freedom from amputation and freedom from death rates were 87.1% and 83.6%, respectively. At the univariate analysis, amputation (p < 0.0001, OR: 9.65, 95%CI: 3.7-25.19), mortality (p = 0.0001, OR: 9.88, 95%CI: 3.19-30.57), and cumulative event rates (p < 0.001, OR: 14.45, 95%CI: 6.1-34.21), were significantly different between the two groups according to NLR value. Multivariate analysis showed that a high baseline NLR value was an independent predictor of unfavorable outcomes in all enrolled patients. Consistently, at ROC analysis, a preoperative NLR > 5 was strongly associated with all outcome occurrences. CONCLUSION: Preoperative NLR value seems to be strongly related to ALI outcomes in this unselected population. The largest series should be evaluated to confirm present results.