Iliac vein obstruction: accuracy of Direct Multidetector Computed Tomographic Venography and duplex ultrasound.

OBJECTIVES: To evaluate the accuracy of direct computed tomographic venography (DCTV) and duplex ultrasound (DUS) in the identification of iliac vein obstruction in highly symptomatic patients with severe chronic venous disease (CVD) compared with intravascular ultrasound (IVUS). METHODS: this study involved patients who had advanced CVD (CEAP C3-6). All patients underwent DCTV, venous duplex scanning, and IVUS. The presence of iliac vein obstruction was detected, and degree of obstruction was classified into 3 grades (grade I, 0% to 49%; grade II, 50% to 79%; and grade III, 80% or greater). The sensitivity, specificity, PPV, NPV, and accuracy were calculated for each modality compared with IVUS. Inter-observer agreement was assessed using the κ coefficient. RESULTS: of 94 patients with CVD, IVUS identified iliac vein obstruction in 55 (58.5%) patients (25.5% was grade 1, 27.3% was grade 2, 47.3% was grade 3). The sensitivity, specificity of DCTV in diagnosing obstruction was (96%, 95% in grade 1; 100%, 100% grade 2; 100%, 100% in grade 3, respectively). The sensitivity, specificity of DUS was (63.9%, 65% in grade 1; 68%, 82% in grade 2, and 70%, 85% in grade 3, respectively). The overall agreement of DUS was 0.73 (95% CI, 0.70-0.79), and DCTV was 0.96 (95% CI, 0.91- 0.97). CONCLUSIONS: DUS is a reasonable initial imaging modality for the identification of significant iliac vein obstruction. DCTV provides an accurate reproducible imaging for accurate estimation needed for treatment planning. ADVANCES IN KNOWLEDGE: Direct CT Venography provides accurate reproducible radiological information required for treatment planning of patients with Iliac vein obstruction including accurate assessment of site of obstruction, its morphology, and degree of obstruction and it can replace the use of indirect CT venography using smaller amount of contrast media with accurate diagnosis.

Effect of physical activity breaks during prolonged sitting on vascular outcomes: A scoping review.

Emerging evidence claims the vascular benefits of varied frequency and duration of physical activity (PA) breaks, whereas the efficacy of varied intensity remains unexplored. We aimed to collate and summate the studies investigating the PA breaks at various intensities on vascular protection. Seven electronic databases were searched for potential studies till Jan 31, 2022. The eligible studies should have administered PA breaks of differing intensities in prolonged sitting postures and explored regional vascular changes [flow mediated dilation (FMD), shear stress, diameter, and blood flow] using ultrasound and novel outcome markers. Two independent reviewers assessed the studies for eligibility after abstract and full-text screen, and appropriate data were extracted to summarise vascular protective effects with PA breaks. Our findings reveal adverse regional vascular outcomes with prolonged sitting (FMD ≈ -1.5%, diameter ≈ -0.06 mm), whereas PA breaks of any intensity were found to improve endothelial functions (FMD ≈ +0.5%, diameter ≈ +0.1 mm, shear ≈ +13 s-1) and mitigate the adverse effects associated with prolonged sitting. Compared with high-intensity activity, low-intensity PA breaks alleviate arterial stiffness and endothelial dysfunction risks.

Penile curvature severity in patients with Peyronie's disease does not correlate with dynamic color doppler duplex ultrasound parameters: findings from a real-life cross-sectional study.

INTRODUCTION: There is inconsistent data regarding the possible inaccuracies in dynamic penile color Doppler duplex ultrasound (CDDU) measurements in men with penile curvature because of Peyronie's disease (PD). We sought to explore the relationship between the degree of penile curvature and CDDU parameters in men with PD. MATERIALS AND METHODS: Comprehensive data from 154 consecutive men presenting with PD as their primary complaint at a single academic center were prospectively collected and analyzed. All men underwent CDDU. Penile curvature was measured using a goniometer at time of maximum erection during CDDU. Patients were grouped based on CDDU parameters into-normal (average peak systolic velocity [PSV] ≥ 35 cm/s and resistance index [RI] ≥ 0.85) and pathological CDDU (average PSV < 35 cm/s and/or RI < 0.85). Descriptive statistics was used to compare the two subcohorts. Linear regression models were fitted to explore the association between the degree of penile curvature and dynamic CDDU parameters. RESULTS: Overall, the median interquartile range (IQR) age was 56 (48-63) years. The median (IQR) PSV and degree of penile curvature were 48.8 cm/s (37.9-58.5) and 40 degrees (30-60), respectively. At CDDU, the degrees of penile curvature were as follows: 10-30 degrees in 63 (40.9%) men, 30-70 degrees in 70 (45.5%) men, and 70-90 degrees in 21 (13.6%) men, respectively. Of all, 116 (75.3%) patients showed a PSV > 35 cm/s and RI ≥ 0.85. Patients with pathologic vs. normal CDDU parameters did not differ in median (IQR) curvature (32.5° [30°-58.7°] vs. 40° [30°-65°], p = 0.5) or in the distribution across curvature range groups. Linear regression analysis revealed that the degree of penile curvature did not significantly correlate with PSV at CDDU (coefficient: 0.06, p = 0.3). CONCLUSIONS: Our study confirms the lack of a significant correlation between the severity of penile curvature and CDDU parameters in men presenting with PD. These findings emerge to be relevant in terms of a more accurate management work-up for PD patients and hold insightful medicolegal implications and in the real-life setting.

Practice-Based Management Data of Consecutive Subjects Assessed for the Median Arcuate Ligament Syndrome at a Single Tertiary Institution.

BACKGROUND: The pathophysiology of median arcuate ligament syndrome (MALS) is poorly understood. The diagnostic process remains inadequately standardized, with an absence of precise criteria to guide therapeutic management. METHODS: We studied consecutive subjects referred to the Department of Angiology at the University Hospital of Zurich over the past 17 years due to suspected MALS. We focused on (1) the imaging criteria that led to diagnosis, notably the results of color duplex ultrasound and the consistency with different imaging tests; (2) the clinical consequences focusing on symptom resolution. RESULTS: We included 33 subjects; in 8 subjects (24.2%), the diagnosis of MALS was retained. The median expiration peak systolic velocity (PSV) on ultrasound was 3.05 (Q1; 2.1-Q3; 3.3). To confirm the sonographic results, either a CT or MRI was performed on all patients, with consistent findings confirming a significant stenosis. Seven patients underwent surgery, all involving arcuate ligament release. Four procedures were laparoscopic, one was via laparotomy, and two were robot-assisted. Additionally, two patients required angioplasty with stenting as a secondary intervention. Only two (28.6%) of the seven operated patients experienced a relief of symptoms. None experienced a relief of symptoms following secondary angioplasty, despite stent patency. The prevalence of psychiatric disorders was comparable between patients with retained and rejected diagnoses, 38% and 36%, respectively. CONCLUSIONS: Our study confirmed sonography and CT/MRI consistency. However, most patients with MALS did not benefit from invasive treatment. The majority (83%) of patients without MALS were diagnosed with alternative conditions, mainly functional disorders.

Unusual Evidence of Fat Embolism in the Subclavian Vein Detected by High-Intensity Transient Signals.

Fat emboli may occur in patients after traumatic fractures or orthopedic procedures; however, their clinical detection is a very rare finding. Here, we describe a 77-year-old female who was admitted to the emergency department with a fracture of the right humerus. We diagnosed fat embolism after an ultrasound of the right subclavian vein. The embolism was detected by high-intensity transient signals present on the spectral Doppler. While these signals are well known for microembolization in transcranial Doppler, to our knowledge this is the first case report in the medical literature to observe and describe high-intensity transient signals seen in the upper extremities by spectral Doppler. Although it is unusual to detect a fat embolism in transit, we believe clinicians should be aware of this finding, particularly when evaluating high-risk patients.

Maximal Systolic Acceleration and Near-Infrared Fluorescence Imaging With Indocyanine Green as Predictors for Successful Lower Extremity Revascularization.

BACKGROUND: Patients with lower extremity arterial disease (LEAD) frequently require revascularization procedures. Currently used diagnostic methods are insufficient in predicting successful outcomes and focus on macrovascular rather than microvascular state. Several promising modalities to increase diagnostic accuracy are emerging, including maximal systolic acceleration (ACCmax), measured by duplex ultrasound (DUS). For the assessment of tissue perfusion, near-infrared fluorescence (NIR) imaging using indocyanine green (ICG) demonstrates promising results. This study aims to identify the usefulness of combining these two methods for macrovascular and microvascular perfusion assessment to predict successful clinical outcomes. METHODS: A retrospective study was performed collecting preinterventional and postinterventional DUS and ICG NIR fluorescence imaging measurements from LEAD patients undergoing revascularization. The correlation between the preinterventional and postinterventional perfusion parameters, described as the delta (Δ) ACCmax and ΔICG NIR fluorescence parameters, were analyzed. Improvements in perfusion parameters were compared to clinical outcomes, defined as improvement in pain-free walking distance, freedom from rest pain, or tendency toward wound and ulcer healing. RESULTS: A total of 38 patients (42 limbs) were included. ACCmax and ICG NIR fluorescence perfusion parameters improved significantly after revascularization (p<0.001). Patients with a poor clinical outcome had a significantly lower improvement of both parameters after revascularization (p<0.001-0.016). Lack of correlation was found between the delta of ACCmax and ICG NIR fluorescence imaging. Multiple non-congruent improvements of macrovascular parameters (ACCmax) and perfusion (ICG NIR fluorescence) were seen within patients. However, for all patients with a successful clinical outcome, at least one parameter improved. CONCLUSION: Combining ACCmax and ICG NIR fluorescence imaging revealed improvement in at least one parameter within all patients with a successful clinical outcome. This study highlights the potential of assessing both the macrovascular state and tissue perfusion following lower extremity revascularization, as both appear to reflect different aspects of vascularization. CLINICAL IMPACT: Numerous techniques have been developed to assess tissue perfusion to predict clinical outcomes following revascularization in patients with peripheral artery disease. However, none are widely implemented in clinical practice. This study emphasized the importance of employing multiple modalities from different perspectives for more accurate prediction. By focusing on both the macrovascular state and tissue perfusion, clinicians can better guide themselves in their treatment strategies.

Current Diagnostic and Therapeutic Challenges in Superficial Venous Thrombosis.

Superficial venous thrombosis (SVT) is a fairly common disorder, characterized by the formation of thrombi inside superficial veins, with or without an associated inflammatory reaction. Its evolution is frequently self-limited. However, serious complications may change this clinical course with extension to deep vein thrombosis (DVT) and pulmonary embolism (PE). SVT shares similar risk factors with DVT and is frequently associated with the presence of varicose veins. However, the occurrence of non-varicose veins could conceal risk factors such as malignancies, thrombophilia, or Buerger's disease. While the clinical diagnosis is generally straightforward, additional diagnostic evaluations are often necessary. Duplex ultrasound (DUS) is an invaluable tool that provides the location of SVT, the proximity to the sapheno-femoral junction, and the clot length, all of which influence the decision for optimal management. The treatment of SVT should be symptomatic, pathogenic (limiting the extension of thrombosis), and prognostic (to prevent complications). There are several guidelines that provide recommendations, and despite the need for more consensus and for further studies, the treatment of SVT should be mainly medical, including anticoagulation in specific clinical situations and symptom relief, with invasive treatment in a minority of cases. Initiation, intensity, and length of anticoagulant treatment should be based on the eventual risk of progression to DVT or PE, which can be high, intermediate, or low, based on the location of SVT and the clot length. Our review summarizes the evaluation and proper management of SVT and highlights the importance of a shared decision within the heart team regarding this condition in order to prevent further complications.

High-frequency ultrasound with superb microvascular imaging: a potential tool for ultrasound assessment in patients with giant cell arteritis.

Objective: The objective of this study was 2-fold: first, to evaluate whether superb microvascular imaging (SMI) could be used to visualize neovascularization in temporal arteries, and, second, to evaluate the diagnostic performance of high frequency ultrasound with SMI using an extended protocol in patients with suspected giant cell arteritis (GCA). Methods: This retrospective study comprised 120 patients consecutively examined with an extended CDU protocol (temporal, facial, axillary, subclavian, brachiocephalic, and carotid arteries) between 2020 and 2022. Of all patients, 107 had no previous GCA diagnosis and 13 had a previous GCA diagnosis. SMI was used to evaluate neovascularization in the temporal arteries. Arteritis were characterized as low- or medium-echogenic, homogeneous wall thickening, with or without a positive compression sign in the temporal arteries. The Halo count, i.e., the number of temporal and axillary artery segments with signs of arteritis, was evaluated. The reference was clinically diagnosed GCA confirmed after ≥6-month follow-up. Results: Of the eligible 107 patients with new suspected GCA, 33 (31%) received a clinical GCA diagnosis. Neovascularization was detected in 14 patients (43%). Patients with neovascularization displayed a higher halo count [median 6 (25th-75th percentile 4.75-7) vs. 3 (2-4-4), p = 0.005]. CDU of only the temporal arteries showed sensitivity and specificity (95% confidence intervals) of 94% (80-100%) and 100% (95-100%), respectively. The addition of extra-cranial arteries increased the sensitivity to 100%. Of the 13 patients investigated for suspected relapse, three had a clinically confirmed relapse. One of them displayed neovascularization together with other signs of inflammation. Conclusions: We show for the first time that inflammatory neovascularization of the temporal arteries can be detected by SMI. Neovascularization is associated with a more-widespread cranial disease. The value of neovascularization should be further investigated, especially for the detection of GCA relapse.

Advances in Vascular Imaging: A Comparative Analysis of Doppler Ultrasound and Multidetector CT for Lower Limb Peripheral Arterial Disease Diagnosis.

Background This study explores the comparison between Doppler ultrasound and multidetector CT angiography (MDCTA) in diagnosing peripheral arterial disease (PAD), emphasizing the urgent need for precise and minimally invasive methodologies in vascular medicine. PAD, stemming from atherosclerosis, manifests as reduced blood flow and symptoms, such as claudication, requiring timely and accurate diagnosis for optimal treatment outcomes. Doppler ultrasound emerges as an option, offering a non-invasive and cost-effective approach. Conversely, MDCTA provides intricate images, albeit with associated risks, such as radiation exposure and potential complications from contrast agents. This research rigorously evaluates the efficacy, safety, and cost-efficiency of these modalities, aiming to provide clinicians with valuable insights for informed decision-making, ultimately enhancing standards of patient care. Methodology In this prospective study conducted at Saveetha Medical College, Chennai, 34 patients diagnosed with PAD were enrolled to compare the efficacy of duplex ultrasound and MDCTA in identifying arterial lesions. Statistical analysis comprised kappa statistics and contingency tables to evaluate the concordance between the modalities, with sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) being calculated. Exclusions were made for patients with contraindications to MDCTA, those under 18 years of age, severe renal impairment, and allergies to contrast agents. This research examined the diagnostic accuracy of both imaging techniques, aiming to provide valuable insights into their effectiveness in identifying arterial lesions associated with PAD. Statistical analysis This investigation studied the efficacy of Doppler ultrasound and MDCTA in diagnosing PAD, with a particular focus on comparing the accuracy of Doppler ultrasonography (DUS) against MDCTA using sensitivity, specificity, and Cohen's kappa coefficient. Through segmental analysis, valuable insights were garnered into the diagnostic precision of DUS across various arterial segments. The results underscored the significance of DUS as a safe, cost-effective, and non-invasive alternative that complements the utility of MDCTA. This comprehensive assessment sheds light on the comparative strengths of both modalities, offering invaluable guidance for clinicians in selecting optimal diagnostic approaches for PAD assessment. Statistical analysis was conducted using the Statistical Package for the Social Sciences (IBM SPSS Statistics for Windows, IBM Corp., Version 24.0, Armonk, NY). Results The sensitivity of ultrasonography (USG) arterial Doppler in evaluating the supra-inguinal, femoropopliteal segments, and infrapopliteal segments was 87.5%, 100%, and 75.32%, respectively. The specificity in evaluating supra-inguinal, femoropopliteal segments, and infrapopliteal segments was 100%, 96.01%, and 83.06%, respectively. The agreement between the two modalities (USG arterial Doppler and CT angiography) obtained by Cohen's kappa analysis with respect to the aortoiliac region and femoropopliteal region was very good (0.91). For infrapopliteal vessels, it was only moderate (0.76). Conclusion Duplex ultrasound emerges as an indispensable tool in the investigation of PAD, offering safety, affordability, and non-invasiveness alongside high diagnostic accuracy and substantial concordance with MDCTA.

Long-Term Results of Surgical Treatment for Popliteal Artery Entrapment Syndrome.

INTRODUCTION: Popliteal artery entrapment syndrome (PAES) is a rare disease of the lower limbs, mainly affecting young patients, due to extrinsic compression of the neurovascular bundle at the popliteal fossa. The aim of this study was to describe our experience during a median 15-year period. METHODS: Patients treated for PAES in our institution from 1979 to 2024 were included. Preoperative, intraoperative, and postoperative data were analyzed. RESULTS: A total of 47 patients with a total of 78 limbs were treated. Duplex ultrasound with active maneuvers was performed in all limbs (100%). Angiography was performed in almost all patients (97.4%), computed tomography angiography in 56 (71.8%), and magnetic resonance angiography in 22 (28.2%). Concerning surgical treatment, musculotendinous section was performed in 60 limbs (76.9%), and autologous venous bypass was achieved in 18 limbs (23.1%). The rates for freedom from target lesion revascularization-meaning that no significant stenosis or occlusion during follow-up required revascularization-and 15-year primary patency were 92.4% and 98%, respectively. CONCLUSION: Long-term results of surgical treatment for PAES seem to be very satisfying. Myotomy with or without arterial reconstruction using venous bypass can lead to good patency at 15 years of follow-up.

Clinical outcomes after treatment of incompetent saphenous vein combined with segmental popliteal vein reflux.

OBJECTIVE: This study aimed to evaluate whether differences exist in the quality of life changes and complication rates after treatment of incompetent saphenous vein (ISV) based on the presence of segmental popliteal vein reflux (SPVR). METHODS: Patients who underwent treatment for ISV from July 2016 to July 2021 were included and divided into two groups: patients without deep venous reflux (DVR) and patients with SPVR. Patients with axial DVR, a history of deep vein thrombosis, a history of orthopedic surgery, previous venous treatment, and no postoperative follow-up were excluded from the study. Duplex ultrasound examination was performed preoperatively and at 6 and 12 months postoperatively. RESULTS: The study included 233 patients (398 limbs), and 50 (64 limbs) had SPVR. Differences were not observed in gender, age, body mass index, distribution of clinical class according to Clinical-Etiology-Anatomy-Physiology classification, laterality, treatment method, and preoperative Venous Clinical Severity Score or Aberdeen Varicose Vein Questionnaire scores between the two groups with SPVR or without DVR. Furthermore, the Venous Clinical Severity Score and Aberdeen Varicose Vein Questionnaire scores at 6 and 12 months postoperatively were improved in both groups, although without significant differences. A significant difference was not observed in the rate of postoperative complications between the groups based on the presence of SPVR (1.8% vs 1.6%: P = .896). The SPVR improvement rate after ISV treatment was 25% (16/64), and patient-reported outcomes in patients combined with SPVR improved independent of treatment modality, saphenous vein treatment section, and postoperative SPVR improvement. CONCLUSIONS: Complication rates and clinical outcomes after ISV treatment did not differ in the presence of SPVR. In patients with SPVR, after ISV treatment, quality of life improved regardless of treatment modality, saphenous vein treatment section, and postoperative SPVR improvement.

Pedal Acceleration Time An Alternative Tool To Ankle-Brachial Index In Peripheral Arterial Disease.

INTRODUCTION: Ankle-Brachial Index (ABI) is a well-established diagnostic tool for evaluating peripheral arterial disease (PAD). Limitations in its application led to the development of alternative diagnostic methods, including Toe-Brachial Index (TBI) and Transcutaneous Pressure of Oxygen (TcPO2), yet these are not as widely available as ABI. Recently, Pedal Acceleration Time (PAT), has gained popularity as a new tool to assess PAD, requiring only an ultrasound. This study seeks to further establish the correlation between ABI and PAT, determining whether PAT can be a reliable alternative for diagnosing and assessing the severity of PAD. METHODS: ABI and PAT were measured in patients attending our consult with no history of vascular or endovascular surgery. Limbs with unmeasurable ABI were excluded. Patients were categorized into groups based on their PAD stage according to the Fontaine classification. Patient demographics, comorbidities and respective ABI and PAT were analysed. RESULTS: Sixty-nine patients (114 limbs) were included in the study. Mean age 68 ± 11.7 years, 78.3% male and 33.3% diabetic patients. Fifty-three claudicant limbs (46.5%) and 26 limbs (22.8%) with chronic limb threatening ischemia. Pearson correlation coefficient between ABI and PAT, showed a strong negative correlation (r= -0.78; p<0.01). Mean ABI and PAT for limbs in Fontaine stage I were 0.94 ± 0.17 and 82.0 ± 27.4 ms; Fontaine stage IIa 0.69 ± 0.21 and 141.3 ± 57.8 ms; Fontaine stage IIb 0.54 ± 0.14 and 173.4 ± 65.1 ms; Fontaine stage III 0.43 ± 0.15 and 216 ± 33.2 ms; Fontaine stage IV 0.49 ± 0.17 and 206.7 ± 78.1 ms, respectively. CONCLUSION: Our study suggests an inverse correlation between ABI and PAT, in accordance with the findings published in the literature, thus supporting the use of PAT as an easily reproducible and efficient alternative to ABI for evaluating the severity of PAD.

Should all critical care patients with a central venous catheter in situ be screened for central catheter related thrombosis?

There are many studies on central catheter related thrombosis (CCRT), however, there are significantly fewer studies focusing on the incidence and evolution of CCRT in the adult critical care population. This article reviews data collected from observational studies that have performed bedside duplex ultrasound for surveillance of CCRT and discuss if we should routinely screen for CCRT. The reported CCRT incidence is 17-38%, with most thrombus being detectable on ultrasound within seven days of line placement. Nearly all CCRT are designated as asymptomatic (no associated pulmonary embolism (PE) or deep vein thrombosis (DVT)) and no significant changes in mortality rates amongst patients that develop CCRT were reported. Based on the evidence reviewed, we do not recommend screening routinely for CCRT in the adult critical care population.

Pelvic vein thrombosis in patients with pelvic venous disorders.

OBJECTIVE: To assess the incidence of pelvic vein thrombosis (PVT) and outcomes of anticoagulant therapy for PVT in patients with pelvic venous disorders (PeVDs). METHODS: This prospective cohort study included 588 female patients with PeVDs underwent clinical examination followed by duplex ultrasound of the pelvic veins in 2021-2023. Patients with PVT were administered with anticoagulant therapy in an outpatient setting using low molecular weight heparins at a therapeutic dose. RESULTS: PVT was detected in 7.6% of patients with PeVDs and was symptomatic in 28.8% of them. The majority of asymptomatic patients had thrombosis in only one of the parametrial veins (90.6%). Anticoagulant therapy resulted in the PVT symptoms relief in all patients within 10 days and recanalization of the pelvic veins in 1-3 months. CONCLUSION: In our study, PVT was diagnosed in 7.6% of patients with PeVDs. Anticoagulant therapy is effective and safe in resolving PVT symptoms.

The sonographic features of lymph node venous networks and flow patterns in patients with primary chronic venous disease.

BACKGROUND: Our study aims to enhance the understanding of lymph node venous networks (LNVNs) by summarising their anatomical, sonographic features, and reflux patterns. METHOD: We examined 241 legs from 141 patients with primary chronic venous disease (CVD) using duplex ultrasound. RESULTS: The findings indicated variations in the shape, size, vascularity, and echogenicity of LNVN. The superficial inguinal lymph node with reflux appeared slightly larger, exhibiting higher velocities in the hilar artery. Regarding connections, venous flow within LNVN was predominantly drained through the saphenofemoral junction (SFJ), anterior accessory great saphenous vein (AAGSV), and great saphenous vein (GSV). A significant number of LNVNs were observed to be associated with anterolateral thigh tributaries. The study also identified valve cusps within LNVN. CONCLUSION: This study revealed a 12% prevalence of primary LNVN. Understanding the anatomical and haemodynamic features of LNVN informs treatment strategies and potentially helps prevent the recurrence of varicose veins.

Predicting future occlusion or stenosis of lower extremity bypass grafts using artificial intelligence to simultaneously analyze all flow velocities collected in current and previous ultrasound examinations.

Objective: Routine surveillance with duplex ultrasound (DUS) examination is recommended after femoral-popliteal and femoral-tibial-pedal vein bypass grafts with various intervals postoperatively. The presently used methodology to analyze bypass graft DUS examination does not use all the available data and has been shown to have a significant rate for missing impending bypass graft failure. The objective of this research is to investigate recurrent neural networks (RNNs) to predict future bypass graft occlusion or stenosis. Methods: This study includes DUS examinations of 663 patients who had bypass graft operations done between January 2009 and June 2022. Only examinations without missing values were included. We developed two RNNs (a bidirectional long short-term memory unit and a bidirectional gated recurrent unit) to predict bypass graft occlusion and stenosis based on peak systolic velocities collected in the 2 to 5 previous DUS examinations. We excluded the examinations with missing values and split our data into training and test sets. Then, we applied 10-fold cross-validation on training to optimize the hyperparameters and compared models using the test data. Results: The bidirectional long short-term memory unit model can gain an overall sensitivity of 0.939, specificity of 0.963, and area under the curve of 0.950 on the prediction of bypass graft occlusion, and an overall sensitivity of 0.915, specificity of 0.909, and area under the curve of 0.912 predicting the development of a future critical stenosis. The results on different bypass types show that the system performs differently on different types. The results on subcohorts based on gender, smoking status, and comorbidities show that the performance on current smokers is lower than the never smoker. Conclusions: We found that RNNs can gain good sensitivity, specificity, and accuracy for the detection of impending bypass graft occlusion or the future development of a critical bypass graft stenosis using all the available peak systolic velocity data in the present and previous bypass graft DUS examinations. Integrating clinical data, including demographics, social determinants, medication, and other risk factors, together with the DUS examination may result in further improvements. Clinical Relevance: Detecting bypass graft failure before it occurs is important clinically to prevent amputations, salvage limbs, and save lives. Current methods evaluating screening duplex ultrasound examinations have a significant failure rate for detecting a bypass graft at risk for failure. Artificial intelligence using recurrent neural networks has the potential to improve the detection of at-risk bypass graft before they fail. Additionally, artificial intelligence is in the news and is being applied to many fields. Vascular surgeons need to know its potential to improve vascular outcomes.

Penetrating injury of the common femoral vein followed by local deep vein thrombosis: A case report.

This case report discusses a unique scenario in which a 19-year-old patient with a penetrating wound in the common femoral vein developed deep vein thrombosis in response to life-threatening bleeding. The report highlights our thoughts on managing an isolated truncal venous injury leading to deep vein thrombosis, emphasizing the significance of surgical exploration in vascular trauma and the feasibility of employing non-invasive imaging diagnosis in preoperative planning.

A Study of Valvular Incompetencies in the Lower Limb Veins Using Doppler Ultrasound Findings.

INTRODUCTION: Varicose veins (VV) are one of the most common pathologies associated with the venous system of the lower limb. In the Indian population, its incidence is higher, and it is one of the most commonly encountered cases in the hospital. The study aimed to note the widely affected anatomical structure in male and female varicose patients using Doppler ultrasound (DU) examination findings. METHODS: A total of 200 Doppler ultrasound reports of varicose patients were retrospectively analyzed and categorized based on the affected structure. The demographic data of all cases, such as age, sex, brief history, signs, symptoms, and affected side of the lower limb, was noted. Anatomical structures causing venous refluxes in the saphenous systems, junctions, and perforating venous systems were noted. Pearson's correlation coefficient was applied to find out its association. RESULTS: Out of 200 Doppler reports studied, 133 (67%) were male and 67 (33%) were female patients. The majority, 180 (90%) cases, belonged to C1-C3 stages according to the Clinical, Etiology, Anatomy, and Pathological (CEAP) classification, while 20 (10%) were in C4-C5 stages. Male patients aged between 31 and 40 years were predominantly affected, with their left side being affected most commonly. In female patients, the older age group of 50-60 years was predominantly affected. Great saphenous reflux in the groin due to incompetent terminal valve was noted in 126 (63%) cases. In the perforator venous (PV) system, defects in the medial leg perforator (189 (95%)), posterior leg (92 (46%)), and thigh perforator (20 (10%)) were noted. CONCLUSION: In the present study, the occurrence of varicose veins is due to the involvement of superficial, deep, and perforator veins with varying percentages. Among the structures, the medial leg perforator was predominantly involved, followed by other perforators. Since most patients were in C1-C3 stages, the involvement of deep veins was noted minimally.

Intra-operative duplex ultrasound scanning in renal transplantation: protocol and service requirements.

Intra-operative duplex ultrasound in renal transplantation was first described in 1998 and whilst reported in problematic cases, there are few reports of its routine use and no current published protocols. Since 2013, we have used intra-operative ultrasound in all renal transplants. The formal protocol used since August 2020 is presented as a reference document for other transplant centres. A Canon Aplio 800 ultrasound system with an i22LH8 hockey-stick transducer is used to image the renal cortex and major vessels, and an i8CX1 matrix transducer to image the graft during and after fascial closure. These transducers are fully sterilised with Sterrad and no sheathing of transducers is required. The transplant surgeon scans within the sterile field with the sonographer guiding imaging and adjusting machine settings. Ultrasound findings are discussed between team members including any requirement for interventions. Ultrasound is performed at three stages of the operation: Stage 1: after clamp release identifying issues of graft vascularity including otherwise unrecognised major vessel and anastomotic abnormalities. Stage 2: following ureteric implantation identifying compromised perfusion due to graft rotation or vessel kinking. Stage 3: after fascial closure identifying compromised perfusion due to external compression. Post-operative scanning, including assessment of the collecting system and bladder, is performed routinely on days 1, 3, 7 and 30. The intervention is effective with no early graft losses or peri-operative vascular thromboses. The requirements for service provision are significant including the availability of additional transducers, and sonographers with expertise in intra-operative scanning able to attend after-hours for extended periods.