Creating a Sustainable Foundation for IR Services and Training in Sub-Saharan Africa: 5-Year Update on the Road2IR Initiative.

PURPOSE: To evaluate the growth and quality of an interventional radiology (IR) training model designed for resource-constrained settings and implemented in Tanzania as well as its overall potential to increase access to minimally invasive procedures across the region. MATERIALS AND METHODS: IR training in Tanzania began in October 2018 through monthly deployment of visiting teaching teams for hands-on training combined with in-person and remote lectures. A competency-based 2-year Master of Science in IR curriculum was inaugurated at the nation's main teaching hospital in October 2019, with the first 2 classes graduating in 2021 and 2022. Procedural data, demographics, and clinical outcomes were collected and analyzed throughout the duration of this program. RESULTS: From October 2018 to July 2022, 1,595 procedures were performed in Tanzania: 1,236 nonvascular and 359 vascular, all with local fellows as primary interventional radiologists. Of these, 97.2% were technically successful, 95.2% were without adverse events, and 28.9% were performed independently by Tanzanian fellows and faculty with no difference in adverse event and technical success rates (P = .63 and P = .90, respectively), irrespective of procedural class. Ten IR physicians graduated from this program during the study period, followed by another 3 per year going forward. Partner training programs in Uganda and Rwanda mirroring this model commenced in 2023 and 2024, respectively. CONCLUSIONS: The reported training model offers a practical and effective solution to meet many of the challenges associated with the lack of access to IR in sub-Saharan Africa.

Virtual vascular surgery interest group during the coronavirus disease 2019 pandemic.

OBJECTIVES: Early exposure to vascular surgery at the medical student level positively influences one's decision to apply into an integrated vascular surgery residency program. Vascular surgery interest groups (VSIGs) are student-run and aim to facilitate such exposure, traditionally via in-person events. Social distancing during the coronavirus disease 2019 pandemic disrupted these interactions. This is a description of the virtual activities of a VSIG group during the 2020-2021 academic year and highlights their impact among medical students. METHODS: The virtual activities of the VSIG at the Yale School of Medicine were reviewed. Students received surveys prior and after activities to assess their impact. Preactivity and postactivity surveys using Likert scale (1 = completely disagree; 5 = completely agree) were administered and compared. Statistical significance was achieved with a P value of less than .05. RESULTS: A total of five virtual events were held: an Introductory Session (October 2020), a Simulation Session (November 2020), a Research Night (January 2021), a Journal Club (February 2021), and a National Match Panel (April 2021). The surveys of three events (Introductory Session, Simulation Session, and National Match Panel) were analyzed. Attendance at these events were 18, 55, and 103 respectively. The average presurvey response rate was 51.2% and the average postsurvey response rate was 27.46%. Students agreed that the Introductory Session increased their knowledge about vascular surgery as a subspecialty (4.22 ± 0.67) and that the session was valuable to their time (4.33 ± 1.00). The Simulation Session increased student's comfort with knot tying from 1.73 ± 0.89 to 3.21 ± 1.25 (P < .001). Students reported an increased understanding of residency program selection (2.39 ± 1.10 vs 3.21 ± 1.12; P = .018), the Electronic Residency Application Service application (2.16 ± 1.01 vs 3.00 ± 0.88; P = .007), and letters of recommendation (2.45 ± 1.07 vs 3.14 ± 1.17; P = .04). Students particularly had a significant increase in the understanding of the logistics of residency interviews, which were held virtually that year for the first time (1.84 ± 0.96 vs 3.29 ± 1.20; P < .001). CONCLUSIONS: Virtual VSIG activities were feasible and effective during the pandemic in promoting student engagement and interest in vascular surgery. Despite lifting social distancing measures, the virtual format could become a valuable tool to expand outreach efforts of the vascular surgery community to recruit talented medical students.

Utility of Hook Sign in the Diagnosis of Median Arcuate Ligament Syndrome.

BACKGROUND: Median arcuate ligament syndrome (MALS) is a clinical syndrome caused by compression of the celiac artery by the median arcuate ligament that often manifests with nonspecific abdominal pain. Identification of this syndrome is often dependent on imaging of compression and upward bending of the celiac artery by lateral computed tomography angiography, the so-called "hook sign." The purpose of this study was to assess the relationship of radiologic characteristics of the celiac artery to clinically relevant MALS. METHODS: An institutional review board-approved retrospective chart review from 2,000 to 2,021 of 293 patients at a tertiary academic center diagnosed with celiac artery compression (CAC) was performed. Patient demographics and symptoms of 69 patients who were diagnosed with symptomatic MALS were compared to 224 patients without MALS (but with CAC) per electronic medical record review. Computed tomography angiography images were reviewed and the fold angle (FA) was measured. The presence of a hook sign (defined as a visual FA < 135°), as well as stenosis (defined as >50% of luminal narrowing on imaging) were recorded. Wilcoxon rank-sum test and Chi-squared test were used for comparative analysis. Logistic model was run to relate the presence of MALS with comorbidities and radiographic findings. RESULTS: Imaging was available in 59 patients (25 males, 34 females) and 157 patients (60 males, 97 females) with and without MALS, respectively. Patients with MALS were more likely to have a more severe FA (120.7 ± 33.6 vs. 134.8 ± 27.9, P = 0.002). Males with MALS were also more likely to have a more severe FA compared with males without MALS (111.1 ± 33.7 vs. 130.4 ± 30.4, P = 0.015). In patients with body mass index (BMI) >25, MALS patients also had narrower FA compared with patients without MALS (112.6 ± 30.5 vs. 131.7 ± 30.3, P = 0.001). The FA was negatively correlated with BMI in patients with CAC. The hook sign and stenosis were associated with diagnosis of MALS (59.3% vs. 28.7%, P < 0.001, and 75.7% vs. 45.2%, P < 0.001, respectively). In logistic regression, pain, stenosis, and a narrow FA were statistically significant predictors of the presence of MALS. CONCLUSIONS: The upward deflection of the celiac artery in patients with MALS is more severe compared with patients without MALS. Consistent with prior literature, this bending of the celiac artery is negatively correlated with BMI in patients with and without MALS. When demographic variables and comorbidities are considered, a narrow FA is a statistically significant predictor of MALS. Regardless of MALS diagnosis, a hook sign was associated with narrower FA. While demographics and imaging findings may inform MALS diagnosis, clinicians should not rely on a visual assessment of a hook sign but should quantitatively measure the anatomic bending angle of the celiac artery to assist with the diagnosis and understand the outcomes.

Sex differences in long-term outcomes of patients with deep vein thrombosis.

OBJECTIVE: Sex differences in short-term outcomes of patients with deep vein thrombosis (DVT) have been reported, but differences in long-term outcomes remain poorly characterized. This study aimed to evaluate sex differences in long-term mortality, venous thromboembolism (VTE)-related mortality, and bleeding-related mortality in patients with DVT at a tertiary care center. METHODS: A retrospective chart review from 2012 to 2018 of all consecutive patients diagnosed with DVT was performed. Patients were grouped by sex, and baseline characteristics and treatment modalities were compared. Long-term outcomes of recurrent VTE, bleeding, and related mortalities were analyzed. Multivariable regression analysis was performed to determine factors associated with overall mortality. RESULTS: A total of 1043 (female = 521 and male = 522) patients with DVT were captured in this study period. Female patients were older (64.7 vs 61.6 years old, p = 0.01) and less likely to be obese (68.2% vs. 71.1%, p = 0.04),but had a higher average Caprini score (6.73 vs 6.35, p = 0.04). There was no difference in anatomic extent of DVT, association with PE, and severity of PE between sexes. Most patients (80.5%) were treated with anticoagulation, with no differences in choice of anticoagulant or duration of anticoagulation between females and males. Male patients were more likely to undergo catheter-directed thrombolysis (CDT) for DVT (4.2% vs 1.7%, p = 0.02) and PE (2.7% vs 0.9%, p = 0.04). Female patients were more likely to receive systemic thrombolysis for PE (2.9% vs 1.1%, p = 0.05). After an average 2.3 years follow-up, there was significantly higher bleeding complications among females (22.2% vs 16.7%, p = 0.027). The overall mortality rate was 33.5% and not different between males and females. Females were more likely to experience VTE-related mortality compared to males (3.3% vs 0.6%, p = 0.002). On regression analysis, older age (OR = 1.04 [1.03-1.06]), cancer (OR = 7.64 [5.45-10.7]), and congestive heart failure (OR = 3.84 [2.15-6.86]) were independently associated with overall mortality. CONCLUSIONS: In this study, there was no difference in overall long-term mortality between sexes for patients presenting with DVT. However, females had increased risk of long-term bleeding and VTE-related mortality compared to males.

Revisiting the Exhibits-Medical Student Reflections on Changes to the Institutional Portraiture at a US Medical School.

BACKGROUND: Yale School of Medicine's (YSM) Sterling Hall of Medicine (SHM) has historically been lined with large oil paintings of mostly White men, despite over a century of Black and female enrollment. These spaces can be seen as exclusionary to students underrepresented in medicine, and may result in decreased well-being and adversely affect academic performance. Student-led activism has resulted in recent changes to these walls, including the addition of images of women faculty, and artwork by students, faculty, and staff. OBJECTIVE: We aimed to evaluate how recent changes to longstanding historical portraiture in SHM affected students' reflections on being in that space. DESIGN: This was a qualitative study based on semi-structured interviews conducted virtually. PARTICIPANTS: Second- to fourth-year YSM medical students were interviewed. APPROACH: Qualitative interviews were used to gauge students' impressions of how they perceived both the original and updated artwork and portraiture, as well as the overall physical environment. KEY RESULTS: Nine interviews were conducted, with interviewees describing the portraiture as reflective of YSM's institutional values. They related this to other aspects of an exclusionary environment, and noted that they created belonging at YSM within smaller communities. Students recognized and expressed appreciation for the changes to the portraiture, particularly the increase in diverse representation, and they noted stark contrasts to the prior space. While they describe positive attitudes regarding changes in SHM's exhibited portraiture and art, they also expressed skepticism about whether these changes were performative or whether they reflected true commitment to reform. CONCLUSIONS: This study depicts how the portraiture and physical environment of a medical school affects medical students, and that interventions to reform institutional portraiture can have considerable impact on students' attitudes regarding their medical school experiences.

Cryoablation of Venous Malformations: A Systematic Review.

This study aimed to review systematically the efficacy, safety, and technical aspects of cryoablation in the treatment of venous malformations (VMs) and to provide the groundwork for future studies. A literature search for clinical studies utilizing percutaneous cryoablation of VMs was performed. All clinical studies related to primary or secondary treatment of VMs with percutaneous cryoablation were included in this review. These selected studies were evaluated for patient characteristics, cryoablation technique, technical success, lesion size and pain scores before and after cryoablation, and adverse outcomes. Random effects analysis of postprocedural changes in lesion volume and pain scores was performed. There were 54 patients with 55 cases of cryoablation of VMs. Of these cases, 27 recorded changes in lesion volume and 31 recorded changes in pain scores. The weighted mean postprocedural decrease in lesion size was 92.0% (raw average, 71.7%). The weighted mean reduction in pain score was 77% (raw average, 78.2%). Considering all treated cases (55), complete resolution of symptoms was seen in 35 cases (63.6%) and overall (complete or partial) improvement in 52 cases (94.5%). Common postprocedural symptoms included pain, bruising, swelling and numbness lasting less than 2 weeks. There were two major adverse events (3.7%), with both cases due to persistent dysesthesia. Patients with a history of prior sclerotherapy demonstrated lower preprocedural and postprocedural pain scores (4.7 and 1.3) than patients without prior treatments (5.8 and 2.8). Cryoablation of VMs appears to be potentially safe and effective on limited short-interval follow-up.

Image-guided percutaneous strategies to improve the resectability of HCC: Portal vein embolization, liver venous deprivation, or radiation lobectomy?

Despite considerable advances in surgical technique, many patients with hepatic malignancies are not operative candidates due to projected inadequate hepatic function following resection. Consequently, the size of the future liver remnant (FLR) is an essential consideration when predicting a patient's likelihood of liver insufficiency following hepatectomy. Since its initial description 30 years ago, portal vein embolization has become the standard of care for augmenting the size and function of the FLR preoperatively. However, new minimally invasive techniques have been developed to improve surgical candidacy, chief among them liver venous deprivation and radiation lobectomy. The purpose of this review is to discuss the status of preoperative liver augmentation prior to resection of hepatocellular carcinoma with a focus on these three techniques, highlighting the distinctions between them and suggesting directions for future investigation.

Disparities in access to endovenous treatment options in chronic lower extremity superficial venous insufficiency: A national 7-year analysis.

OBJECTIVE: The goal of this study was to analyze trends in treatment access for chronic superficial venous disease and to identify disparities in care. METHODS: This retrospective study was exempt from institutional review board approval. The American College of Surgeon National Surgical Quality Improvement Program database was used to identify patients who underwent vein stripping (VS) and endovenous procedures for treatment of chronic superficial venous disease. Endovenous options included radiofrequency ablation (RFA) and laser ablation. Data was available from 2011 to 2018 and demographic information was extracted for each patient identified by Current Procedural Terminology codes. For all racial and ethnic groups, trend lines were plotted, and the relative rate of change was determined within each specified demographic. RESULTS: There were 21,025 patients included in the analysis. The overall mean age was 54.2 years, and the majority of patients were female (64.8%). In total, 27.9%, 55.2%, and 16.9% patients underwent VS, RFA, and laser ablation, respectively. Patients who received laser ablation were older (P < .001). Hispanic ethnicity was associated with significantly lower odds of receiving endovascular thermal ablation (EVTA) over VS (odds ratio [OR], 0.71; 95% confidence interval [CI], 0.64-0.78; P < .001). American Indian/Alaska Native patients were more likely to receive EVTA over VS (OR, 4.02; 95% CI, 2.48-6.86); similarly, Native Hawaiian/Pacific Islander patients were more likely to receive EVTA over VS, although this difference was not statistically significant (OR, 1.44; 95% CI, 0.93-2.27). On multinomial regression, Hispanic patients were less likely to receive RFA over VS, whereas American Indian/Alaskan Native patients were more likely to receive RFA over VS. In all racial and ethnic groups, the percentage of endovenous procedures increased, whereas vein stripping decreased. CONCLUSIONS: Based on a hospital-based dataset, demographic indicators, including age, sex, race, and ethnicity, are associated with differences in endovenous treatments for chronic superficial venous insufficiency suggesting disparities in obtaining minimally invasive treatment options among certain patient groups.

ClotTriever system for mechanical thrombectomy of deep vein thrombosis.

There is increasing evidence that early and comprehensive removal of thrombus in deep vein thrombosis is associated with improved outcomes, including decreased incidence of post-thrombotic syndrome and debilitating long-term symptoms. Catheter-directed thrombolysis is effective for the rapid removal of clot, but it is associated with high bleeding risk. Percutaneous mechanical thrombectomy is a highly effective method for the removal of clot without the use of systemic or catheter-directed thrombolytic therapy. The Inari ClotTriever system (Inari Medical Inc., CA, USA) is a thrombectomy device, which is approved for deep vein thrombosis by the US FDA in 2017. Herein we review the current treatment strategies using the ClotTriever system, its specifications, indications and current state of literature.

Deep venous thrombosis is a common disease that causes blood clots in the veins. Complete removal of clot is associated with better outcomes, including decreased incidence of post-thrombotic syndrome (symptoms including leg heaviness, pain, cramping, swelling and discomfort). The ClotTriever system (Inari Medical, Inc., CA, USA) is a device approved for the removal of clot in veins without using clot-busting medications that increase bleeding risk. This review describes the types of devices, indications and current research.

Twenty-Seven-Year Retrospective Review of Hemoptysis from Systemic Collaterals Following Pulmonary Arteriovenous Malformation Embolization.

OBJECTIVE: To determine the prevalence of hemoptysis secondary to post-embolization systemic collaterals and review the recurrence rate and treatment outcomes. METHODS: The records of 930 patients with PAVM (801 with known or possible HHT), from a single HHT center between July 2, 1996 and July 22, 2021, were searched for a single lifetime episode of hemoptysis secondary to post-embolization systemic collaterals. Embolization was performed with permanent particles or gelatin slurry. Clinical features and treatment outcomes of identified patients were reviewed. RESULTS: Twenty-eight embolization procedures have been performed in 9 patients with post-PAVM embolization systemic artery collateral reperfusion. This included 8 patients with known HHT. Permanent particles were used in 5 cases and gelatine slurry was used in 19 cases. Due to the recurrence of hemoptysis, four patients required four embolizations each, two patients required three embolizations and two patients required two embolizations. Chronic unresolving hemoptysis was the presentation in 5 patients and massive hemoptysis requiring ICU admission in 4. The lifetime prevalence and incidence of hemoptysis secondary to systemic artery reperfusion in HHT patients was estimated to be 1.0% and 0.05%, respectively. Bronchial artery origin was most common (8 patients). In the first patient treated at this center, a major adverse event resulting in myocardial infarct and stroke occurred with the use of 300-500-micron permanent particles. This was presumed to be due to left-to-right shunting and subsequent systemic embolization. Subsequent patients were treated with gelatin sponge slurry without adverse events. This patient ultimately expired due to large volume hemoptysis, in the setting of bilateral diffuse PAVMs. A second patient, with history of childhood bronchial artery coil embolization, expired from large volume hemoptysis while awaiting lobectomy. In two cases, patients underwent surgery, including one lobectomy and one pneumonectomy, for recurrent hemoptysis (requiring at least five hospital admissions). The remaining five patients achieved prolonged resolution of hemoptysis with endovascular treatment alone. CONCLUSION: Lifetime prevalence of hemoptysis secondary to PAVM post-embolization systemic collaterals is rare, but recurrence is high. In this limited series, embolization with gelatin sponge slurry appeared safe, although surgical resection may ultimately be required in refractory and multifocal disease.

Inferior Mesenteric Artery Snorkel for Endovascular Treatment of a Large Degenerating Saccular Aneurysm.

Objective: Preservation of the inferior mesenteric artery (IMA) during endovascular aortic aneurysm repair (EVAR) is necessary for prevention of mesenteric ischaemia in the case of chronically occluded coeliac and superior mesenteric arteries (SMA). This case report presents an approach in a complex patient. Methods: A 74 year old man with hepatitis C cirrhosis and recent non-ST elevation myocardial infarction presented with an infrarenal degenerating saccular aneurysm (58 mm), chronically occluded SMA and coeliac artery, and 9 mm IMA with high grade ostial stenosis. He also had concomitant atherosclerosis of the aorta with a narrow distal aortic lumen of 14 mm, which tapered to 11 mm at the aortic bifurcation. Endovascular attempts to cross long segment occlusions of the SMA and coeliac artery were unsuccessful. Thus, EVAR was performed using the unibody AFX2 endograft and chimney revascularisation of the IMA using a VBX stent graft. One year follow up demonstrated regression of the aneurysm sac to 53 mm with patent IMA graft and no endoleak. Conclusion: Few reports have described techniques for endovascular preservation of the IMA, which is a necessary consideration in the context of coeliac and SMA occlusion. Because open surgery was not a good option for this patient, available endovascular options had to be weighed up. An added challenge was the exceptionally narrow aortic lumen in the context of aortic and iliac atherosclerotic disease. It was decided that the anatomy was prohibitive for a fenestrated design and extensive calcification was too limiting for gate cannulation of a modular graft. Thus a bifurcated unibody aortic endograft with chimney stent grafting of the IMA was successfully used as a definitive solution.

The role of preoperative toxicology screening in patients undergoing bariatric surgery.

BACKGROUND: Some programs and insurers may require patients to undergo toxicology screening despite lack of evidence that this practice affects postoperative outcomes. OBJECTIVES: To understand the prevalence of screening positive on toxicology testing in the bariatric surgical population and to examine the association between testing positive and important surgical outcomes. METHODS: We performed a retrospective review of patients who underwent laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass from an academic health system from 2017-2020. We described the rate of preoperative toxicology positivity as determined by serum and urine testing. We examined the association between toxicology positivity and outcomes of preoperative length, 30-day complications (bleeding, venous thromboembolism, leak, wound infection, pneumonia, urinary tract infection, and myocardial infarction), readmissions, and 1-year weight loss using chi-square and t-test analysis. RESULTS: Of 1057 patients, there were 134 patients (12.7%) who had positive toxicology testing. Of these, 37 (28%) were positive for opiates and 21 (16%) were positive for cotinine. Mean preoperative length was 381.8 days (standard deviation [SD], 222.5) for patients with positive testing versus 287.8 days (SD, 151.5; P = 1.00) for negative testing. Toxicology positivity was not associated with readmissions (5.2% versus 4.3%, X2 = 0.22; P = .64). The loss to follow-up at 1 year was 32.5%. There was no association with 1-year mean change in body mass index (mean of loss 12.23kg/m2 [SD, 5.61]) versus mean of loss 12.74 (SD, 6.44; P = .20)]. CONCLUSIONS: Our study is the first to describe preoperative toxicology positivity rates. We found no association between toxicology positivity and preoperative length, readmissions, or weight loss. Given its lack of impact on outcomes, toxicology testing prior to bariatric surgery may be an unnecessary burden on patients and healthcare, with regard to cost and wait times.

Comparative Analysis of Percutaneous Drainage versus Operative Drainage of Intra-Abdominal Abscesses in a Resource-Limited Setting: The Tanzanian Experience.

Background: Intra-abdominal abscesses (IAAs) are a major cause of morbidity and mortality worldwide. While image-guided percutaneous abscess drainage (PAD) has become the standard of care in many countries, over half of the global population does not have access to interventional radiology (IR) and are left with surgery as the only option for source control. Objective: The purpose of this study is to evaluate the development, implementation, and role of a PAD service in a resource-limited setting. Method: A retrospective cohort study was performed on all patients who underwent percutaneous or surgical abscess drainage (SAD) of IAAs at Tanzania's national referral hospital from 10/2018 to 4/2021. Patients were identified through a match case search of institutional records and inclusion was confirmed through manual chart review. Demographics, patient presentation, procedural data, and clinical outcomes were recorded in a password-encrypted database and compared between groups. Findings: Sixty-three patients underwent abscess drainage: 32 percutaneously and 31 surgically. In the PAD group, there was a 100% technical success rate and a 0% complication rate. In the SAD group, there was a 64.5% technical success rate and ten deaths within 30 days (32.3%), and one additional complication requiring major therapy (3.2%) (p < 0.001). Conclusion: Results from this study demonstrate that PAD can be performed with high technical success and without complication by trained IR physicians in Tanzania. The development of a successful PAD program exemplifies the drastic need to support the growth of IR services in this setting.

Prevalence and Characteristics of Patients with Median Arcuate Ligament Syndrome in a Cohort Diagnosed with Celiac Artery Compression.

BACKGROUND: Median arcuate ligament syndrome (MALS) is a frequent differential diagnosis in patients with postprandial abdominal symptoms, but diagnosis remains challenging. The aim of this study was to identify characteristics of patients who had MALS compared with non-MALS patients among a cohort of patients diagnosed with celiac artery compression (CAC). STUDY DESIGN: An IRB-approved retrospective chart review (2000 to 2021) of patients at our institution with a discharge diagnosis of CAC was performed. Medical record review for clinical symptoms and findings consistent with MALS was performed. RESULTS: Two hundred ninety-three patients with a diagnosis of CAC were identified; 59.7% were women, and average age was 63.9 ± 20.2 years. Sixty-nine (23.5%) patients with CAC had MALS. There were no significant differences in sex or race between MALS and non-MALS patients, but MALS patients were younger (55.7 vs 68.1, p < 0.001). There was no significant difference in gastrointestinal comorbidities between the 2 groups. Patients with MALS were less likely to have diabetes (12.5% vs 26.9%), renal disease (4.6% vs 8.2%), hypertension (41.5% vs 70.3%), mesenteric atherosclerotic disease (14% vs 61.9%), and peripheral artery disease (15.0% vs 39.7%). CONCLUSIONS: We demonstrate a novel observation that MALS patients tend to have fewer atherosclerotic characteristics than non-MALS patients with CAC. Patients in our study with MALS were more likely to be younger, women, and presenting with epigastric pain. MALS patients had a significantly lower incidence of diabetes, hypertension, renal disease, mesenteric artery disease, and peripheral arterial disease compared with the non-MALS group. An important clinically relevant feature of MALS patients may be their lack of atherosclerotic phenotype compared with non- MALS patients with CAC.

A narrative review on the application of high-intensity focused ultrasound for the treatment of occlusive and thrombotic arterial disease.

Objectives: High-intensity focused ultrasound (HIFU) is a noninvasive therapeutic modality with a variety of applications. It is approved for the treatment of essential tremors, ablation of prostate, hepatic, breast, and uterine tumors. Although not approved for use in the treatment of atherosclerotic arterial disease, there is a growing body of evidence investigating applications of HIFU. Currently, percutaneous endovascular techniques are predominant for the treatment of arterial pathology; however, there are no endovascular techniques of HIFU available. This study aims to review the state of current evidence for the application of HIFU in atherosclerotic arterial disease. Methods: All English-language articles evaluating the effect of HIFU on arterial occlusive and thrombotic disease until 2021 were reviewed. Both preclinical and human clinical studies were included. Study parameters such as animal or clinical model and outcomes were reviewed. In addition, details pertaining to settings on the HIFU device used were also reviewed. Results: In preclinical models, atherosclerotic plaque progression was inhibited by HIFU, through decreases in oxidized low-density lipoprotein cholesterol and increases in macrophage apoptosis. Additionally, HIFU promotes angiogenesis in hindlimb ischemic models by the upregulation of angiogenic and antiapoptotic factors, with increased angiogenesis at higher line densities of HIFU. HIFU also promotes thrombolysis and conversely induces platelet activation at low frequencies and higher intensities. Various clinical studies have attempted to translate some of these properties and demonstrated positive clinical outcomes for arterial recanalization after thrombotic stroke, decreased atherosclerotic plaque burden in carotid arteries, increase in tissue perfusion and a decrease in diameter stenosis in patients with atherosclerotic arterial disease. Conclusions: In current preclinical and clinical data, the safety and efficacy of HIFU shows great promise in the treatment of atherosclerotic arterial disease. Future focused studies are warranted to guide the refinement of HIFU settings for more widespread adoption of this technology.

Cryptogenic acute lower extremities and multiorgan ischemia in an 8-year-old girl.

Pediatric acute limb ischemia is rare but can have devastating effects on children. The most common causes of acute limb ischemia in the pediatric age group are iatrogenic injury during cardiac catheterization and traumatic vessel injury. Embolic events have been described less often. We present the case of an 8-year-old girl with cryptogenic extensive bilateral lower extremity ischemia and embolization to multiple visceral organs. Our findings have highlighted the importance of interdisciplinary workup, timely intervention, and the advantage of intraoperative imaging for revascularization.