Research Presentation Session: Vascular

RPS 415 - Examining portal venous thrombosis: diagnosis and management strategies

February 28, 13:00 - 14:30 CET

7 min
Vascular complications of liver transplantation in children, early diagnosis and management
Andrés Felipe Mejía León, Bogotá / Colombia
Author Block: A. F. Mejía León, L. M. Acosta, L. Acosta, J. E. Chaustre Soledad, S. Trujillo, J. M. Perez, G. Caviedes; Bogotá/CO
Purpose: The aims of this study were to: (1)Describe the most common early vascular complications of liver transplant in the paediatric population. (2) Show the main imaging findings through different case examples of our institution. (3) Compare the radiological findings found in our cohort of patients with those described in the literature.
Methods or Background: The number of paediatric patients undergoing transplantation has grown exponentially in recent years, enhancing the importance of early detection of the different complications related to early and late postoperative stage in the clinical scenario. The radiologist and radiologist-in-training must be aware of these complications and early imaging manifestations.Understanding the findings in different imaging modalities, is essential to a proper approach, with Doppler ultrasound being one of the most important modalities for early detection of complications. Through a multimodality approach we intend to show the importance of each of these modalities for early diagnosis, and likewise, to describe the type of management according to the postoperative time. The management of these complications is not limited to surgical management. The role of interventional radiology is increasingly recognised, depending on the type of complication and the postoperative time being a fundamental pillar in the management of these patients.
Results or Findings: Regarding the main vascular complications in the postoperative period of liver transplants in paediatrics, we found greater prevalence of arterial thrombosis, follow by stenosis of the hepatic artery and hepatic veins. Some of these cases were managed by interventional radiology, obtaining favorable results.
Conclusion: Findings do not differ from those described in literature presenting a similar frequency of appearance. When complications are detected soon in the early postoperative period, this group of patients benefit from earlier interventions, which translates into better clinical outcomes.
Limitations: Only Latin American patients were included limiting the scope of this study.
Funding for this study: No funding was obtained for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: Low risk research hence no ethical approval was required.
7 min
Reliability and accuracy of tomographic 3D ultrasound for grading vessel stenosis: a phantom study
Adel Ahmad Alzahrani, Jeddah / Saudi Arabia
Author Block: A. A. Alzahrani1, M. Aslam2, S. R. Sultan3; 1Makkah/SA, 2London/UK, 3Jeddah/SA
Purpose: The aim of this phantom study was to assess the accuracy of 3-D tomographic ultrasound (t3DUS) for grading stenosis, using the manufacturer's measurements as the gold standard. The percentage of maximum stenosis was obtained using 2-D ultrasound (2DUS) and t3DUS imaging techniques on a peripheral vascular phantom, including channels with 50%, 75% and 90% stenosis.
Methods or Background: A high-resolution premium Philips Elite ultrasound imaging system (Philips Healthcare, Bothell, WA, USA) was used to obtain maximum percentage of stenosis from a peripheral vascular phantom using 2DUS and t3DUS (PIUR Imaging GmbH, Vienna, Austria) imaging techniques. Inter-operator reproducibility and accuracy of DR and AR 2DUS and t3DUS in measuring maximum stenosis percentage were assessed.
Results or Findings: The inter-operator reproducibility of DR and AR 2DUS and t3DUS maximum stenosis measurements between operator A and B (n = 90 for each operator per technique) was excellent (DR 2DUS, ICC = 0.96, 95% confidence interval [CI]: 0.900.98, p < 0.001
Conclusion: Free-hand t3DUS is a reproducible and accurate imaging method for grading stenosis. The inter-operator reproducibility of t3DUS for grading stenosis was excellent with a low coefficient of variation. The mean difference in stenosis measurements from manufacturer reference values for all channels was lower in t3DUS than in 2DUS. There was significant under- and overestimation of 2-D DR and AR, respectively, compared with Tomographic 3-DUS for grading vessel stenosis.
Limitations: Not applicable for this study.
Funding for this study: This study was funded by the King Abdullah Medical City KAMC.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: Not applicable for this study.
7 min
Reducing the radiation doses and contrast volume in CT portal venography for patients with sinusoidal obstruction syndrome on a second-generation dual-layer spectral CT
Yiran Wang, Zhengzhou / China
Author Block: Y. Wang; Zhengzhou/CN
Purpose: The aim of this study was to investigate the feasibility of 60keV virtual monoenergetic images (VMIs) of spectral CT imaging, combined with low contrast dose for patients with sinusoidal obstruction syndrome (SOS) by comparing with polyenergetic CT images.
Methods or Background: In the prospective study, 28 patients who underwent dual-layer spectral CT scanning were divided into two group, group A (control group,120kVp) and group B (experimental group, 100 kVp). 95 mL of 350 mgI/mL iodixanol was administered to the control group, and personalised injection protocol (25 mgI/kg/s with a duration of 17 seconds) was used for group B, respectively. CT numbers of the portal veins (PVs), liver parenchyma, and subcutaneous fat tissue in the abdomen were measured by the region of interest (ROI). The standard deviation of the images was interpreted as the objective image noise (IN). The diagnostic acceptability (DA) and sharpness of PV margins were obtained using a 5-point score.
Results or Findings: Hepatic heterogeneity, puddle-like or micronodular appearance, peripheral distribution of heterogeneity, clover-like sign, splenomegaly, as well as the subjective impression of the observer were significantly associated with SOS diagnosis. The observers' confidence in the diagnosis of SOS increased significantly in group B. The CT value of liver in group B was higher than group A, conversely, SNR and CNR were lower (P<0.05). Compared with group A, the effective radiation dose of group B decreased by 26.6%. The average iodine loads were 33.3 g and 28.3±3.6 g, respectively.
Conclusion: Compared to conventional polychromatic CT images, 60 keV VMIs of 100 kVp improved diagnostic performance of sinusoidal obstruction syndrome in portal venography imaging with reduced contrast media and lower radiation dose.
Limitations: Our sample is small in spite of a long period of study limiting the scope of this study.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was approved by the First affiliated hospital of Zhengzhou university Ethics committee.
7 min
Development and validation of a new score for selecting the best vascular access for liver cancer intra-arterial procedures (trans-femoral or trans-radial access score)
Alessandro Maresca, Rome / Italy
Author Block: A. Maresca, L. Tenore, A. Posa, A. Contegiacomo, M. Lippi, L. Natale, R. Iezzi; Rome/IT
Purpose: Intra-arterial procedures play an important role in the treatment of liver neoplastic lesions. Trans-radial artery access has been considered for IR procedures; the choice of a femoral or radial approach is based on the operator’s experience or preference. This study aims to develop a CT-based scoring system for selecting the best candidates for trans-radial approach.
Methods or Background: All the patients who underwent TACE using a trans-radial approach were included. Patients’ clinical data, pre-procedural CT-image and lesion location were registered and a CT scoring system was developed. Procedural complexity, based on angiographic and procedural variables, was evaluated. The relationship between procedural difficulty and the categorical variables were statistically tested.
Results or Findings: One hundred and eight-two trans-radial TACE procedures were analysed; only 93 patients were retrospectively included in our study due to the adequacy of the data. The parameters which resulted significant (p<0.0001) in determining the procedural difficulty were represented by the aortic arch diameter, the suprarenal aortic diameter, the celiac trunk takeoff angle and the anatomical variants of celiac trunk anatomy. Multivariate regression analysis identified four variables like predictors of procedural complexity: radial caliber < 2.6 mm, left subclavian artery angle < 65 degrees, suprarenal aorta diameter > 33 mm, celiac trunk takeoff angle > 81 degrees. Using these four variables, a 4-point risk score was developed (1-2: easy – 3-4: complex).
Conclusion: TAS (transradial access) score seems to be useful to predict complexity of endovascular interventions through a transradial approach.
Limitations: The most important limitation of the study is that it is focused on the learning curve of a single operator on a single procedure (lobar chemoembolisation). Data are not applicable to all operators and/or other procedures and do not take into account individual operator variabilities and differences in procedure complexity.
Funding for this study: No funding was obtained for this study
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The study was led under the approval of the local ethics committee and the institutional review board (IRB).
7 min
Direct Percutaneous Thrombolysis (DPT): an effective method of salvaging thrombosed native arteriovenous fistula
Vignesh Selvamurugan, Palakkad / India
Author Block: V. Selvamurugan1, R. Prasad2, R. R. Yadav3, P. Hasani4, A. Israr3, H. Lal3, S. Sharma3; 1Madurai, Ut/IN, 2Delhi/IN, 3Lucknow/IN, 4Vadodara/IN
Purpose: Thrombosed arteriovenous fistulas (AVFs) are either treated by thrombectomy or pharmaco-mechanical thrombolysis with or without percutaneous balloon angioplasty. In this study, we have described an effective and economical technique of salvaging these fistulas using a 20–22-gauge spinal needle and urokinase - direct percutaneous thrombolysis (DPT).
Methods or Background: This prospective study comprised of 148 patients out of which 120 patients presented with AVF thrombosis and were divided into two groups; those with no obvious stenosis on ultrasound (n=38) and second with venous stenosis (n=82). Remaining 28 patients developed thrombosis post angioplasty for venous stenosis. Percutaneous injection of urokinase into the thrombus was done under ultrasound guidance, followed by balloon angioplasty if there was associated stenosis.
Results or Findings: In 38 patients who didn’t have any stenosis, 32 AVFs were successfully thrombolysed by DPT, with technical success of 84.2%. Remaining six patients required angioplasty because of chronic nature of clot. In 82 patients who had venous stenosis, 80 cases were treated successfully by DPT followed by angioplasty with technical success of 97.5%. In third group (n=28), who developed thrombosis post angioplasty, 100% success rate was noted. The mean length of thrombus was 31.4 ± 4.6 mm and mean diameter of thrombosed vein was 10.5 ± 1.2 mm. There were no major complications encountered during the procedure.
Conclusion: Ultrasound guided DPT with urokinase is a safe and economical option for salvaging thrombosed AVF without vascular stenosis that does not need angioplasty.
Limitations: The main limitation was inherent selection bias, as we did not enroll patients with very long thrombosed segment and grossly dilated thrombosed venous segment. There was also lack of comparison between the various groups enrolled.
Funding for this study: No funding was obtained for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: All procedures performed in the studies involving human participants were in accordance with the ethical standards of the institutional research committee. Retrospective analysis so ethical approval not taken.
7 min
Relevance of preoperative and early postoperative USG vascular assessment in predicting haemodialysis AV fistula failure in chronic kidney disease patients
Shikhar Gupta, Delhi / India
Author Block: S. Gupta, M. Ahmad; Aligarh/IN
Purpose: The increasing prevalence of chronic kidney disease (CKD), coupled with advancements in the diagnosis and treatment of renal diseases and improvements in life expectancy, has led to a greater number of patients requiring hemodialysis. The preferred method of vascular access for haemodialysis is AV fistula formation; however, it is associated with a high rate of failure.
Methods or Background: In this prospective study, 40 CKD patients planned for initiation of maintainence hemodialysis were selected and preoperative ultrasound vessel mapping and early postoperative ultrasound assessment on day seven were utilised to establish criteria for predicting early fistula failure. Preoperative ultrasound mapping was employed to assess various factors such as cephalic vein diameter, compressibility, and colour flow, radial and brachial artery diameter, peak systolic velocity, and intimal wall calcification. Postoperatively, ultrasound examinations were conducted on day seven and at six weeks to evaluate fistula blood volume and detect any complications.
Results or Findings: A significant association between fistula failure and factors such as cephalic vein diameter, brachial artery diameter, intimal vessel wall calcification, and comorbid conditions like diabetes mellitus was observed. Furthermore, the blood flow at day seven was notably lower in the failure group compared to those with a functioning fistula and any fistula with blood flow <154 ml/min on day 7 may be predictive of early fistula failure.
Conclusion: Preoperative vessel mapping and early postoperative ultrasonography is indispensable for patients who require AV fistula formation for hemodialysis and provide valuable information for selecting suitable vessels in successful fistula creation and enable early intervention to salvage a failing fistula after the surgery. By utilising these, healthcare professionals can make informed decisions and take necessary steps to optimise the outcomes of AV fistula formation in patients undergoing haemodialysis.
Limitations: No limitations were identified in this study.
Funding for this study: No fundings were received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: Institutional Ethics Committee approved this study.
7 min
Imaging of abdominal arteries: intra-individual comparison of Relaxation-Enhanced Angiography without contrast and triggering (REACT) with 4D contrast-enhanced MR angiography at 3T
Jan Paul Janssen, Cologne / Germany
Author Block: J. P. Janssen1, L. Goertz1, K. Kaya1, J-P. Grunz2, T. Persigehl1, K. Weiss3, L. Pennig1, C. H. Gietzen1; 1Cologne/DE, 2Würzburg/DE, 3Hamburg/DE
Purpose: The main aim of this study was to compare a Novel Relaxation-Enhanced Angiography without contrast and Triggering (REACT) sequence with 4D contrast-enhanced magnetic resonance angiography (4D CE-MRA) for imaging of the abdominal arteries.
Methods or Background: Thirty patients (35.7±16.8 years; 10 males) who received abdominal vessel imaging using a standardised protocol at 3T were included in this retrospective, single centre study. The protocol comprised both 4D CE-MRA and flow-independent REACT (Compressed SENSE factor 10, reconstructed voxel size 0.8x0.8x0.9 mm3) sequences. Two radiologists independently evaluated abdominal arteries for the presence of stenosis, variants, and other vascular findings (e.g., dissection). Subjective image quality of arteries was assessed using a 4-point Likert scale (1=non-diagnostic, 4=excellent). Vessels were classified based on size: (1) aorta (supra- and infrarenal segments), (2) large (celiac trunk, superior mesenteric artery, renal arteries), (3) medium (splenic artery, common and proper hepatic artery) and (4) small (gastric arteries, hepatic arteries, inferior mesenteric artery) arteries.
Results or Findings: REACT yielded a median acquisition time of 304 s. Considering 4D CE-MRA as the standard of reference, REACT achieved a sensitivity of 87.5% and a specificity of 100% for relevant (≥50%) stenosis while detecting 89.3% of vascular variants and 100% of other findings. Vessel quality was comparable between both sequences at the aorta (4D CE-MRA: 3.94±0.24, REACT: 3.88±0.44; p<0.044) as well as for medium (4D CE-MRA: 2.93±0.96, REACT: 2.77±0.90; p=0.028) and small arteries (4D CE-MRA: 2.15±0.85, REACT: 2.04±0.86; p=0.032). In contrast, 4D CE-MRA yielded slightly higher scores for large arteries (4D CE-MRA: 3.61±0.61, REACT: 3.35±0.72; p<0.001).
Conclusion: REACT provides a good diagnostic performance for the detection of relevant stenosis, variants, and other findings of abdominal arteries while yielding to 4D CE-MRA comparable image quality, underlining its use for non-contrast evaluation of the abdominal vasculature.
Limitations: No limitations were identified in this study.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: The study is retrospective so no ethical approval was sought.
7 min
Vascular access devices registry as a working tool to improve infection control and thromboembolism management in cancer patients
Mikhail Cherkashin, Saint Petersburg / Russia
Author Block: M. Cherkashin, S. Alexandrov, F. Valieva, A. Nikolaev, T. Bolshakova, E. Ilyukhin, N. Berezina; Saint-Petersburg/RU
Purpose: The aim of this study was to discuss permanent vascular access devices registry development and implementation.
Methods or Background: Vascular access devices (port-systems, peripherally implanted central catheters etc) characterised by thrombotic and infectious complications. After device implantation oncology patient can receive different types of anti-tumour therapy in different hospitals and sometimes it's very hard to obtain clear information - which device was implanted, were there any complications etc. The applicable way to exchange clinically important information between hospitals is creation of electronic registers with access for healthcare providers, involved in patient management. We decided to use online platform "Russian Registry of Treatment of Venous Thromboembolism" (NCT03881345) with some customisation, related to central venous devices, concominante blood stream infections, device malfunctions etc.
Results or Findings: Registry was started with 3 hospitals operating with paediatric oncology in St Petersburg. System development includes relevant steps: level of access (in each hospital should be dedicated owner with total access and each healthcare provider, involved in device management should have rights to upload information); data fields customisation (type of device, place of insertion, technical features during implantation, complications, malfunctions, thrombosis/occlusion, infection, therapy etc). In first month since process was started, 24 cases were uploaded (14 port-a-caths, 8 PICCs, 2 midlines) based on retrospective data we estimate 400-600 cases per year.
Conclusion: Registry is the extremely helpful tool for patient tracking during all stages of cancer treatment. Based on our results, such types of initiatives should be spreaded on city level with all paediatric oncology departments involvement.
Limitations: No information was provided by the submitter.
Funding for this study: This study was funded by the hospital.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was funded approved by Local ethics committee.
7 min
Diagnostic performance of angio-MRI in the evaluation of large vessel vasculitis: preliminary results
Ejona Duka, Varese / Italy
Author Block: E. Duka1, L. Di Meglio1, E. Tombetti1, M. Papa2, G. M. Roda'1, G. Carrafiello1; 1Milan/IT, 2Gragnano Trebbiense/IT
Purpose: The study aims to evaluate diagnostic performance and reproducibility of angio-MRI in the evaluation of patients affected by large vessel vasculitis (Takayasu arteritis and Giant cell arteritis).
Methods or Background: Retrospective analysis of 22 patients affected by large vessel vasculitis that performed angio-MRI in our centre being referred from the Immunology and Rheumatology colleagues. Two readers with five- and two-years’ experience in angio-MRI retrospectively analysed the images. The evaluation regarded the involvement of aorta, supra-aortic trunks, splanchnic vessels and iliofemoral vessels. The inter-observer agreement and reliability was established with Cohen’s kappa test. The diagnostic findings were stated in percentage. The diagnostic performance was expressed in terms of percentage with 95% of interval confidence in terms of sensitivity and specificity.
Results or Findings: Aortic involvement (wall thickening with enhancement) was the commonest finding in 63% of patients. The diagnostic performance was 100% specificity, 80% sensitivity and the inter-reader agreement showed moderate accuracy (κ 0.88).
Conclusion: Angio-MRI represents a valid and reliable tool in the evaluation of patients affected by large cell arteritis, in the diagnosis, management and during follow-up.
Limitations: There is a small number of patients presenting with the pathology since it is a rare disease. More patients could be enrolled in order to develop a more accurate description of MRI signs of this disease.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: No ethics committee approval necessary.
7 min
Usefulness of low-energy virtual monochromatic CT imaging with deep-learning image reconstruction in the delineation of endoleaks after endovascular stent‑graft placement
Takatoshi Higashigawa, Tsu / Japan
Author Block: T. Higashigawa1, Y. Ichikawa1, K. Nakajima2, T. Kobayashi1, K. Domae1, A. Yamazaki1, N. Kato1, H. Sakuma1; 1Tsu/JP, 2Ise/JP
Purpose: The aim of this study was to investigate the usefulness of low-energy virtual monochromatic imaging combined with deep learning image reconstruction (DLIR) in improving the delineation of endoleak after endovascular stent‑graft placement in contrast-enhanced dual-energy CT (DECT).
Methods or Background: Sixty-one consecutive patients (median age, 79 years; 46 men) after endovascular stent-graft placement who underwent contrast-enhanced DECT between December 2021 and February 2023 were studied. Virtual monochromatic 40- and 70-keV images were reconstructed using DLIR (TrueFidelity-H) and conventional hybrid iterative reconstruction (IR) (ASIR-V50%). Contrast-to-noise ratio (CNR) of endoleak on the venous phase CT were calculated. Four different reconstructed image series (hybrid IR and DLIR at two energy levels, 40- and 70-keV) were displayed side-by-side and visually evaluated for endoleak conspicuity on a 5-point comparative scale from 0 (best) to -4 (significantly inferior).
Results or Findings: A total of 30 out of 61 patients had endoleak (type II, 27; type III, 2; type I, 1). CNR of the endoleak were significantly higher in DLIR than in hybrid IR on both 40- and 70-keV images (40-keV, 14.5 ± 7.3 vs 8.6 ± 4.2, p < 0.001; 70-keV, 8.7 ± 4.5 vs 5.5 ± 2.6, p < 0.001). The endoleak conspicuity score for 40-keV DLIR images (Reviewer 1, -0.2 ± 0.4; Reviewer 2, 0.0 ± 0.0) was significantly higher than 40-keV hybrid IR (Reviewer 1, -0.5 ± 0.5; Reviewer 2, -1.0 ± 0.0; p < 0.05), 70-keV DLIR (Reviewer 1, -1.8 ± 0.4; Reviewer 2, -2.0 ± 0.0; p < 0.001) and 70-keV hybrid IR images (Reviewer 1, -1.8 ± 0.4; Reviewer 2, -2.4 ± 0.5; p < 0.001), respectively.
Conclusion: The utilisation of low-energy virtual monochromatic imaging combined with DLIR method improves the delineation of endoleak after endovascular stent-graft placement.
Limitations: Retrospective study limits the scope of this study.
Funding for this study: No funding was was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The current study was conducted with the approval of our institutional review board, and written informed consent was waived because existing clinical CT data were used for this study. The opportunity to opt out of participating in this study was provided by a notice posted on the hospital’s website. No patient indicated an intention to be excluded from this study.

This session will not be streamed, nor will it be available on-demand!