Machine Learning and Omics Analysis in Aortic Aneurysm

Aortic aneurysm is a life-threatening condition and mechanisms underlying its formation and progression are still incompletely understood. Omics approach has brought new insights to identify a broad spectrum of biomarkers and better understand cellular and molecular pathways involved. Omics generate a large amount of data and several studies have highlighted that artificial intelligence (AI) and techniques such as machine learning (ML)/deep learning (DL) can be of use in analyzing such complex datasets. However, only a few studies have so far reported the use of ML/DL for omics analysis in aortic aneurysms. The aim of this study is to summarize recent advances on the use of ML/DL for omics analysis to decipher aortic aneurysm pathophysiology and develop patient-tailored risk prediction models. In the light of current knowledge, we discuss current limits and highlight future directions in the field.

Editor's Choice - Long Term Outcomes After Invasive Treatment of Carotid Artery Stenosis: a Longitudinal Study of German Health Insurance Claims

OBJECTIVE

There is a paucity of observational data including long term outcomes after invasive treatment for carotid artery stenosis.

METHODS

This retrospective study used nationwide insurance claims from the third largest provider in Germany, DAK-Gesundheit. Patients who underwent inpatient carotid endarterectomy (CEA) or carotid artery stenting (CAS) between 1 January 2008 and 31 May 2017 were included. The Elixhauser comorbidity scores from longitudinally linked hospital episodes were used. Kaplan-Meier analysis and the log rank test were used to determine long term stroke free survival. Multivariable regression models were developed to adjust for confounding.

RESULTS

A total of 22 637 individual patients (41.6% female, median age 72.5 years) were included, of whom 15 005 (66.3%) were asymptomatic and 17 955 (79.3%) underwent CEA. After a median of 48 months, 5 504 any stroke or death events were registered. The mortality rate varied between 0.4% (CEA for asymptomatic stenosis) and 2.1% (urgent CAS for acute stroke patients) at 30 days, and between 4.1% and 8.4% at one year, respectively. The rate for any stroke varied between 0.6% (CEA for asymptomatic stenosis) and 2.5% (CAS for symptomatic patients) at 30 days, and between 2.5% and 6.4% at one year, respectively. The combined rate for any stroke and mortality at one year was 6.3% (CEA for asymptomatic stenosis), 8.7% (CAS for asymptomatic stenosis), and 12.5% (urgent CAS for acute stroke patients). After five years, the overall stroke rate was 7.4% after CEA and 9.0% after CAS. In adjusted analyses, both older age and van Walraven comorbidity score were associated with events, while treatment of asymptomatic stenosis was associated with lower event rates.

CONCLUSION

The current study revealed striking differences between previous landmark trials and real world practice. It further suggested excess deaths among invasively treated asymptomatic patients.

Comprehensive Review of Natural Language Processing (NLP) in Vascular Surgery

Objective

The use of Natural Language Processing (NLP) has attracted increased interest in healthcare with various potential applications including identification and extraction of health information, development of chatbots and virtual assistants. The aim of this comprehensive literature review was to provide an overview of NLP applications in vascular surgery, identify current limitations, and discuss future perspectives in the field.

Data sources

The MEDLINE database was searched on April 2023.

Review methods

The database was searched using a combination of keywords to identify studies reporting the use of NLP and chatbots in three main vascular diseases. Keywords used included Natural Language Processing, chatbot, chatGPT, aortic disease, carotid, peripheral artery disease, vascular, and vascular surgery.

Results

Given the heterogeneity of study design, techniques, and aims, a comprehensive literature review was performed to provide an overview of NLP applications in vascular surgery. By enabling identification and extraction of information on patients with vascular diseases, such technology could help to analyse data from healthcare information systems to provide feedback on current practice and help in optimising patient care. In addition, chatbots and NLP driven techniques have the potential to be used as virtual assistants for both health professionals and patients.

Conclusion

While Artificial Intelligence and NLP technology could be used to enhance care for patients with vascular diseases, many challenges remain including the need to define guidelines and clear consensus on how to evaluate and validate these innovations before their implementation into clinical practice.

Natural Language Processing for Literature Search in Vascular Surgery: A Pilot Study Testing an Artificial Intelligence Based Application

Introduction

The use of natural language processing (NLP) for a literature search has been poorly investigated in vascular surgery so far. The aim of this pilot study was to test the applicability of an artificial intelligence (AI) based mobile application for literature searching in a topic related to vascular surgery.

Technique

A focused scientific question was defined to evaluate the performance of the AI application for a literature search and compare the results with the ground truth provided via a traditional literature search performed by human experts. Using pre-defined keywords, the literature search was performed automatically by the AI application through different steps, including quality assessment based on evaluation of the information available and quality filters using indicators of level of evidence, selection of publications based on relevancy filters using NLP, summarisation, and visualisation of the publications via the mobile app. A traditional literature search performed by human experts required 10 hours to check 154 original articles, among which 26 (16.9%) were truly related to the question, 63 (40.9%) related to the field but not to the specific question, and 65 (42.2%) were unrelated. The AI based search was performed in less than one hour, and, compared with traditional search, the method identified 17 original articles (48.6%) truly related to the question (p < .010), 18 (51.4%) related to the field but not to the specific question (p = .26), and no unrelated publications (p < .001). Fifteen truly related articles (88.2%) were identified jointly by the two methods. No significant difference was observed regarding the median number of citations, year of publications, and impact factor of journals.

Discussion

The AI based method enabled a targeted, focused, and time saving literature search, although the selection of publications was not completely exhaustive. These results suggest that such an AI driven application is a complementary tool to help researchers and clinicians for continuous education and dissemination of knowledge.

Artificial intelligence in vascular surgical decision making

Despite advances in prevention, detection, and treatment, cardiovascular disease is a leading cause of mortality and represents a major health problem worldwide. Artificial intelligence and machine learning have brought new insights to the management of vascular diseases by allowing analysis of huge and complex datasets and by offering new techniques to develop advanced imaging analysis. Artificial intelligence-based applications have the potential to improve prognostic evaluation and evidence-based decision making and contribute to vascular therapeutic decision making. In this scoping review, we provide an overview on how artificial intelligence could help in vascular surgical clinical decision making, highlighting potential benefits, current limitations, and future challenges.

Artificial intelligence-based predictive models in vascular diseases

Cardiovascular disease represents a source of major health problems worldwide, and although medical and technical advances have been achieved, they are still associated with high morbidity and mortality rates. Personalized medicine would benefit from novel tools to better predict individual prognosis and outcomes after intervention. Artificial intelligence (AI) has brought new insights to cardiovascular medicine, especially with the use of machine learning techniques that allow the identification of hidden patterns and complex associations in health data without any a priori assumptions. This review provides an overview on the use of artificial intelligence-based prediction models in vascular diseases, specifically focusing on aortic aneurysm, lower extremity arterial disease, and carotid stenosis. Potential benefits include the development of precision medicine in patients with vascular diseases. In addition, the main challenges that remain to be overcome to integrate artificial intelligence-based predictive models in clinical practice are discussed.

Nationwide Study in France To Predict One Year Major Bleeding and Validate the OAC3-PAD Score in Patients Undergoing Revascularisation for Lower Extremity Arterial Disease

OBJECTIVE

Antithrombotic strategies are currently recommended for the treatment of lower extremity artery disease (LEAD) but specific scores to assess the risk of bleeding in these patients are scarce. To fill the gap, the OAC3-PAD bleeding score was recently developed and validated in German cohorts. The aim of this study was to determine whether this score performs appropriately in another real world nationwide cohort.

METHODS

This 10 year retrospective, multicentre study based on French national electronic health data included patients who underwent revascularisation for LEAD between January 2013 and June 2022. The OAC3-PAD score was calculated and from this, the population was classified into four groups: low, low to moderate, moderate to high and high risk. A binary logistic regression model was applied, with major bleeding occurring at one year (defined using the International Classification of Diseases ICD-10) as the dependent variable. The performance of the OAC3-PAD bleeding score was investigated using a receiver operating characteristic curve.

RESULTS

Among 161 205 patients hospitalised for LEAD treatment in French institutions, the one year incidence of major bleeding was 13 672 patients (8.5%). The distribution of the population according to the OAC3-PAD bleeding score was: 88 835 patients (55.1%), 34 369 (21.3%), 27 914 (17.3%), and 10 087 (6.3%) in the low, low to moderate, moderate to high, and high risk groups, respectively; with an incidence of one year major bleeding of 5.0%, 9.8%, 13.2%, and 21.3%. The OAC3-PAD model achieved an AUC of 0.650 to predict one year major bleeding following LEAD repair (95% CI 0.645 - 0.655), with a sensitivity of 0.67 and a specificity of 0.57.

CONCLUSION

This nationwide analysis confirmed the accuracy of the OAC3-PAD model to predict one year major bleeding and served as external validation. Although further studies are required, it adds evidence and perspectives to further generalise its use to guide the management of patients with LEAD.

Automatic Detection of Visceral Arterial Aneurysms on Computed Tomography Angiography Using Artificial Intelligence Based Segmentation of the Vascular System

Introduction

Visceral arterial aneurysms (VAAs) are life threatening. Due to the paucity of symptoms and rarity of the disease, VAAs are underdiagnosed and underestimated. Artificial intelligence (AI) offers new insights into segmentation of the vascular system, and opportunities to better detect VAAs. This pilot study aimed to develop an AI based method to automatically detect VAAs from computed tomography angiography (CTA).

Methods

A hybrid method combining a feature based expert system with a supervised deep learning algorithm (convolutional neural network) was used to enable fully automatic segmentation of the abdominal vascular tree. Centrelines were built and reference diameters of each visceral artery were calculated. An abnormal dilatation (VAAs) was defined as a substantial increase in diameter at the pixel of interest compared with the mean diameter of the reference portion. The automatic software provided 3D rendered images with a flag on the identified VAA areas. The performance of the method was tested in a dataset of 33 CTA scans and compared with the ground truth provided by two human experts.

Results

Forty-three VAAs were identified by human experts (32 in the coeliac trunk branches, eight in the superior mesenteric artery, one in the left renal, and two in the right renal arteries). The automatic system accurately detected 40 of the 43 VAAs, with a sensitivity of 0.93 and a positive predictive value of 0.51. The mean number of flag areas per CTA was 3.5 ± 1.5 and they could be reviewed and checked by a human expert in less than 30 seconds per CTA.

Conclusion

Although the specificity needs to be improved, this study demonstrates the potential of an AI based automatic method to develop new tools to improve screening and detection of VAAs by automatically attracting clinicians' attention to suspicious dilatations of the visceral arteries.

Applications of artificial intelligence for patients with peripheral artery disease

OBJECTIVE

Applications of artificial intelligence (AI) have been reported in several cardiovascular diseases but its interest in patients with peripheral artery disease (PAD) has been so far less reported. The aim of this review was to summarize current knowledge on applications of AI in patients with PAD, to discuss current limits, and highlight perspectives in the field.

METHODS

We performed a narrative review based on studies reporting applications of AI in patients with PAD. The MEDLINE database was independently searched by two authors using a combination of keywords to identify studies published between January 1995 and December 2021. Three main fields of AI were investigated including natural language processing (NLP), computer vision and machine learning (ML).

RESULTS

NLP and ML brought new tools to improve the screening, the diagnosis and classification of the severity of PAD. ML was also used to develop predictive models to better assess the prognosis of patients and develop real-time prediction models to support clinical decision-making. Studies related to computer vision mainly aimed at creating automatic detection and characterization of arterial lesions based on Doppler ultrasound examination or computed tomography angiography. Such tools could help to improve screening programs, enhance diagnosis, facilitate presurgical planning, and improve clinical workflow.

CONCLUSIONS

AI offers various applications to support and likely improve the management of patients with PAD. Further research efforts are needed to validate such applications and investigate their accuracy and safety in large multinational cohorts before their implementation in daily clinical practice.

Automatic measurement of vascular calcifications in patients with aorto-iliac occlusive disease to predict the risk of re-intervention after endovascular repair

OBJECTIVE

There is currently a lack of consensus and tools to easily measure vascular calcification using computed tomography angiography (CTA). The aim of this study was to develop a fully automatic software to measure calcifications and to evaluate the interest as predictive factor in patients with aorto-iliac occlusive disease.

METHODS

This study retrospectively included 171 patients who had endovascular repair of an aorto-iliac occlusive lesion at the University Hospital of Nice between January 2011 and December 2019. Calcifications volumes were measured from CT-angiography (CTA) using an automatic method consisting in 3 sequential steps: image pre-processing, lumen segmentation using expert system and deep learning algorithms and segmentation of calcifications. Calcification volumes were measured in the infrarenal abdominal aorta and the iliac arterial segments, corresponding to the common and the external iliac arteries.

RESULTS

Among 171 patients included with a mean age of 65 years, the revascularization was performed on the native external and internal iliac arteries in respectively: 83 patients (48.5%); 107 (62.3%) and 7 (4.1%). The mean volumes of calcifications were 2759 mm³ in the infrarenal abdominal aorta, 1821 mm³ and 1795 mm³ in the right and left iliac arteries. For a mean follow up of 39 months, TLR was performed in 55 patients (32.2%). These patients had higher volume of calcifications in the right and left iliac arteries, compared with patients who did not have a re-intervention (2274 mm³ vs 1606 mm³, p=0.0319 and 2278 vs 1567 mm³, p=0.0213).

CONCLUSION

The development of a fully automatic software would be useful to facilitate the measurement of vascular calcifications and possibly better inform the prognosis of patients.

Incidence of Contrast-Induced Nephropathy and Post-Operative Outcomes in Patients Undergoing Chimney Endovascular Aortic Aneurysm Repair

Chimney endovascular aortic aneurysm repair (ch-EVAR) has become a valid alternative to treat complex aneurysms but the occurrence of contrast-induced kidney injury (CI-AKI) is poorly known. This study investigated the incidence and the impact of CI-AKI on post-operative outcomes after ch-EVAR. Consecutive patients who underwent ch-EVAR between July 2010 and 2021 were retrospectively included. CI-AKI was defined based on plasma creatinine levels within 7 days after the intervention according to the "Kidney Disease Improving Global Outcomes" (KDIGO) classification. Among 102 patients included, CI-AKI occurred in 14 cases (13.7%). The 30-day post-operative mortality and complications were significantly higher in patients who developed CI-AKI compared with those who did not (50 vs 9.1%, P = .001 and 57.1 vs 20.5%, P = .007). Over a median follow-up of 24 months (3-39), overall mortality was also significantly higher (78.6 vs 33.0%, P = .002). The pre-operative platelet-to-lymphocyte ratio (PLR) was significantly higher in patients who developed CI-AKI (224.5 vs 147.6, P = .008). CI-AKI is frequent after ch-EVAR and is associated with worse post-operative outcomes. This should increase awareness of clinicians to optimize preventive and therapeutic strategies.

Mycotic aortic and left iliac ruptured aneurysm due to Escherichia Coli: a case report and literature overview

Mycotic aneurysm is a life-threatening disease often caused by Salmonella, Staphylococci and Streptococci species. Interestingly, Escherichia Coli (E. Coli) is described as a rare causative agent. We report the case of a patient who developed a mycotic aortic and ruptured left iliac aneurysm due to E. Coli. The patient developed a secondary aortic graft infection due to a mesenteric ischemia with fecal peritonitis. A literature overview of the current knowledge on mycotic aortic aneurysms specifically due to E. Coli is discussed including the clinical characteristics of patients, the management of the disease and the post-operative outcomes.

Diabetes-Induced Changes in Macrophage Biology Might Lead to Reduced Risk for Abdominal Aortic Aneurysm Development

Type 2 diabetes patients are less likely to develop an abdominal aortic aneurysm (AAA). Since macrophages play a crucial role in AAA development, we hypothesized that this decrease in AAA risk in diabetic patients might be due to diabetes-induced changes in macrophage biology. To test this hypothesis, we treated primary macrophages obtained from healthy human volunteers with serum from non-diabetic vs. diabetic AAA patients and observed differences in extracellular acidification and the expression of genes involved in glycolysis and lipid oxidation. These results suggest an increase in metabolism in macrophages treated with serum from diabetic AAA patients. Since serum samples used did not differ in glucose content, these changes are not likely to be caused by differences in glycemia. Macrophage functions have been shown to be linked to their metabolism. In line with this, our data suggest that this increase in macrophage metabolism is accompanied by a shift towards an anti-inflammatory state. Together, these results support a model where diabetes-induced changes in metabolism in macrophages might lead to a reduced risk for AAA development.

Applications of Artificial Intelligence in Non-cardiac Vascular Diseases: A Bibliographic Analysis

Research output related to artificial intelligence (AI) in vascular diseases has been poorly investigated. The aim of this study was to evaluate scientific publications on AI in non-cardiac vascular diseases. A systematic literature search was conducted using the PubMed database and a combination of keywords and focused on three main vascular diseases (carotid, aortic and peripheral artery diseases). Original articles written in English and published between January 1995 and December 2020 were included. Data extracted included the date of publication, the journal, the identity, number, affiliated country of authors, the topics of research, and the fields of AI. Among 171 articles included, the three most productive countries were USA, China, and United Kingdom. The fields developed within AI included: machine learning (n = 90; 45.0%), vision (n = 45; 22.5%), robotics (n = 42; 21.0%), expert system (n = 15; 7.5%), and natural language processing (n = 8; 4.0%). The applications were mainly new tools for: the treatment (n = 52; 29.1%), prognosis (n = 45; 25.1%), the diagnosis and classification of vascular diseases (n = 38; 21.2%), and imaging segmentation (n = 38; 21.2%). By identifying the main techniques and applications, this study also pointed to the current limitations and may help to better foresee future applications for clinical practice.

Short-term outcomes and survival of pyrocarbon hemiarthroplasty in the young arthritic shoulder

HYPOTHESIS

The purpose was to report the short-term outcomes and survival of hemiarthroplasty with a pyrocarbon head (HA-PYC) for the treatment of shoulder osteoarthritis in patients aged ≤ 60 years. We hypothesized that HA-PYC could be an alternative to hemi-metal (avoiding the risk of rapid glenoid erosion) and total shoulder arthroplasty (TSA) (avoiding the risk of rapid glenoid loosening) in an active patient population.

METHODS

Sixty-four consecutive patients (mean age, 53 years) who underwent HA-PYC for glenohumeral osteoarthritis were included. The primary outcome was revision to TSA or reverse shoulder arthroplasty. Secondary outcome measures included functional outcome scores; return to work and sports; and radiographic evaluation of humeral reconstruction quality using the "circle method" of Mears, as well as glenoid erosion severity and progression using the Sperling classification. Patients were reviewed and underwent radiography at an average follow-up of 33 months (range, 24-60 months).

RESULTS

At last follow-up, the rate of survival of the HA-PYC prosthesis was 92%. Revision was performed in 5 patients, with a mean delay of 24 months (range, 15-37 months): 1 conversion to TSA and 4 conversions to reverse shoulder arthroplasty. The Constant score and Subjective Shoulder Value increased from 36 points (range, 26-50 points) to 75 points (range, 69-81 points) and from 35% (range, 20%-50%) to 80% (range, 75%-90%), respectively (P < .001). Postoperatively, 91% of the patients (42 of 46) returned to work and 88% (15 of 17) returned to sport. The severity of preoperative and postoperative glenoid wear (Sperling grade 3 or 4) had no influence on the functional results. Patients who underwent associated concentric glenoid reaming (n = 23) had similar Constant scores and Subjective Shoulder Values (P = .95) to other patients and did not show more progression of glenoid wear. Nonanatomic reconstruction of the proximal humerus (center of rotation of the prosthesis > 3 mm from the anatomic center) occurred in 29% (18 of 62 patients) and was associated with significantly lower functional and subjective results, more complications (subscapularis insufficiency and/or symptomatic glenoid erosion), and a higher risk of revision. The additional 1.5-mm thickness of the metal disc under the pyrocarbon head was found to be the main reason for oversizing of the prosthetic head.

CONCLUSION

HA-PYC is a reliable procedure to treat shoulder osteoarthritis and allows return to work and sports in a young (≤60 years) and active patient population. The severity of glenoid bone erosion or the association with glenoid reaming does not affect functional outcomes and failure risk. By contrast, nonanatomic reconstruction of the proximal humerus after HA-PYC (because of humeral head oversizing) occurred in one-third of the cases and is associated with lower functional outcomes, as well as higher risks of complications and revision.

Incidence of contrast-induced acute kidney injury in patients with acute mesenteric ischemia and identification of potential predictive factors

OBJECTIVE

Contrast-enhanced computed tomography angiography (CTA) is commonly used to investigate acute abdominal conditions, but the risk of contrast-induced acute kidney injury (CI-AKI) has been poorly investigated in patients with acute mesenteric ischemia. The aim of the present study was to evaluate the incidence of CI-AKI in these patients and identify potential predictive factors.

METHODS

Patients admitted for acute mesenteric ischemia who had a diagnostic CTA with contrast medium and a follow-up of creatinine concentration were retrospectively included.

RESULTS

Among 53 patients included, 9 (16.9%) developed CI-AKI. The prevalence of chronic kidney disease did not differ significantly between those who developed CI-AKI and those who did not (33.3 vs 18.2%, p=.372). Plasma total bilirubin and conjugated bilirubin levels were significantly higher in patients who developed CI-AKI (17.5 vs 8.0 μmol/L, p=.013 and 8.0 vs 3.0 μmol/L, p=.031, respectively). The proportion of patients who had revascularization was similar between patients who developed CI-AKI and those who did not (11.1 vs 20.5%, p>.999). No significant difference was observed for 30-day mortality and all-cause mortality for a median follow-up of 168 days (22.2 vs 13.6%, p=.611; and 33.3 vs 61.4%, p=.153, respectively).

CONCLUSION

This study reports the incidence of CI-AKI in patients with acute mesenteric ischemia after diagnostic CTA with contrast medium. Plasma bilirubin levels were a predictive factor of CI-AKI in these patients. The administration of contrast media during revascularization was not associated with an increased risk of CI-AKI.

TREM-1 orchestrates angiotensin II-induced monocyte trafficking and promotes experimental abdominal aortic aneurysm

The triggering receptor expressed on myeloid cells 1 (TREM-1) drives inflammatory responses in several cardiovascular diseases but its role in abdominal aortic aneurysm (AAA) remains unknown. Our objective was to explore the role of TREM-1 in a mouse model of angiotensin II-induced (AngII-induced) AAA. TREM-1 expression was detected in mouse aortic aneurysm and colocalized with macrophages. Trem1 gene deletion (Apoe-/-Trem1-/-), as well as TREM-1 pharmacological blockade with LR-12 peptide, limited both AAA development and severity. Trem1 gene deletion attenuated the inflammatory response in the aorta, with a reduction of Il1b, Tnfa, Mmp2, and Mmp9 mRNA expression, and led to a decreased macrophage content due to a reduction of Ly6Chi classical monocyte trafficking. Conversely, antibody-mediated TREM-1 stimulation exacerbated Ly6Chi monocyte aorta infiltration after AngII infusion through CD62L upregulation and promoted proinflammatory signature in the aorta, resulting in worsening AAA severity. AngII infusion stimulated TREM-1 expression and activation on Ly6Chi monocytes through AngII receptor type I (AT1R). In human AAA, TREM-1 was detected and TREM1 mRNA expression correlated with SELL mRNA expression. Finally, circulating levels of sTREM-1 were increased in patients with AAA when compared with patients without AAA. In conclusion, TREM-1 is involved in AAA pathophysiology and may represent a promising therapeutic target in humans.

Contrast-induced nephropathy in non-cardiac vascular procedures, a narrative review: Part 2

This is Part 2 of a narrative review summarizing the literature on CIN after non-cardiac vascular diagnostic or therapeutic procedures, focusing on peripheral artery disease (PAD) and renal artery stenosis (RAS). Part 1 discussed CIN in relation to aortic aneurysms and carotid stenosis. We comment on the incidence, biomarkers, risk factors, and consequences of CIN in patients with PAD or RAS, as well as on strategies to prevent CIN. Future perspectives in the field of CIN in relation to non-cardiac vascular procedures are also considered.

Contrast-induced nephropathy in non-cardiac vascular procedures, a narrative review: Part 1

Contrast-induced nephropathy (CIN) is an important complication of iodinated contrast medium (CM) administration, which is associated with both short- and long-term adverse outcomes (e.g., cardiorenal events, longer hospital stay, and mortality). CIN has been mainly studied in relation to cardiac procedures, but it can also occur following non-cardiac vascular interventions. This is Part 1 of a narrative review summarizing the available literature on CIN after non-cardiac vascular diagnostic or therapeutic procedures for aortic aneurysm and carotid stenosis. We discuss the definition, pathophysiology, incidence, risk factors, biomarkers, and consequences of CIN in these settings, as well as preventive strategies and alternatives to limit iodinated CM use. Physicians and vascular surgeons should be aware of CM-related adverse events and the potential strategies to avoid them. Clearly, more research in this important field is required.

Feasibility of the Application of Holographic Augmented Reality in Endovascular Surgery Using Microsoft HoloLens Head-Mounted Display

OBJECTIVES

Advances in virtual, augmented (AR) and mixed reality have led to the development of wearable technologies including head mounted displays (HMD). The aim of this study was to investigate the feasibility to use HMD during endovascular surgery.

METHODS

We propose an adaptation of AR-HMD using Microsoft HoloLens. Software was developed to enable visualization of the vascular system during endovascular procedures. A video was performed to present an overview of the device and show its use in real conditions.

RESULTS

The device allowed a successful visualization of perioperative angiography during peripheral angioplasty, carotid angioplasty and aortic aneurysm endovascular repair. The device was operated on voice command, preserving the environment sterility.

CONCLUSION

This video illustrated the feasibility of the application of holographic AR during endovascular intervention and brings perspectives to use artificial-intelligence derived tools for image-guided surgery.

Applications of Head-Mounted Displays and Smart Glasses in Vascular Surgery

OBJECTIVES

Advances in virtual, augmented and mixed reality have led to the development of wearable technologies including head mounted displays (HMD) and smart glasses. While there is a growing interest on their potential applications in health, only a few studies have addressed so far their use in vascular surgery. The aim of this review was to summarize the fundamental notions associated with these technologies and to discuss potential applications and current limits for their use in vascular surgery.

METHODS

A comprehensive literature review was performed to introduce the fundamental concepts and provide an overview of applications of HMD and smart glasses in surgery.

RESULTS

HMD and smart glasses demonstrated a potential interest for the education of surgeons including anatomical teaching, surgical training, teaching and telementoring. Applications for pre-surgical planning have been developed in general and cardiac surgery and could be transposed for a use in vascular surgery. The use of wearable technologies in the operating room has also been investigated in both general and cardiovascular surgery and demonstrated its potential interest for image-guided surgery and data collection.

CONCLUSION

Studies performed so far represent a proof of concept of the interest of HMD and smart glasses in vascular surgery for education of surgeons and for surgical practice. Although these technologies exhibited encouraging results for applications in vascular surgery, technical improvements and further clinical research in large series are required before hoping using them in daily clinical practice.

Management of Vascular Complications during Anterior Lumbar Spinal Surgery Using Mini-Open Retroperitoneal Approach

BACKGROUND

Anterior retroperitoneal spine exposure has become increasingly performed for the surgical treatment of various spinal disorders. Despite its advantages, the procedure is not riskless and can expose to potentially life-threatening vascular lesions. The aim of this review is to report the vascular lesions that can happen during anterior lumbar spinal surgery using mini-open retroperitoneal approach and to describe their management.

METHODS

A systematic literature search was performed according to PRISMA to identify studies published in English between January 1980 and December 2019 reporting vascular complications during anterior lumbar spinal surgery with mini-open retroperitoneal approach. Three authors independently conducted the literature search on PubMed/Medline database using a combination of the following terms: "spinal surgery", "anterior lumbar surgery (ALS)", "anterior lumbar interbody fusion (ALIF)", "lumbar total disc replacement", "artificial disc replacement", "vascular complications", "vascular injuries". Vascular complications were defined as any peri-operative or post-operative lesions related to an arterial or venous vessel. The management of the vascular injury was extracted.

RESULTS

Fifteen studies fulfilled the inclusion criteria. Venous injuries were observed in 13 studies. Lacerations and deep venous thrombosis ranged from 0.8% to 4.3% of cases. Arterial lesions were observed in 4 studies and ranged from 0.4% to 4.3% of cases. It included arterial thrombosis, lacerations or vasospasms. The estimated blood loss was reported in 10 studies and ranged from 50 mL up to 3000 mL. Vascular complications were identified as a cause of abortion of the procedure in 2 studies, representing respectively 0.3% of patients who underwent ALS and 0.5% of patients who underwent ALIF.

CONCLUSION

Imaging pre-operative planning is of utmost importance to evaluate risk factors and the presence of anatomic variations in order to prevent and limit vascular complications. Cautions should be taken during the intervention when manipulating major vessels and routine monitoring of the limb oxygen saturation should be systematically performed for an early detection of arterial thrombosis. The training of the surgeon access remains a key-point to prevent and manage vascular complications during anterior lumbar spinal surgery with mini-open retroperitoneal.