Deciphering Popliteal Artery Aneurysm Patient Diversity: Insights From a Cluster Analysis of the POPART Registry

BACKGROUND

Popliteal artery aneurysms (PAAs) are the most common peripheral aneurysm. However, due to its rarity, the cumulative body of evidence regarding patient patterns, treatment strategies, and perioperative outcomes is limited. This analysis aims to investigate distinct phenotypical patient profiles and associated treatment and outcomes in patients with a PAA by performing an unsupervised clustering analysis of the POPART (Practice of Popliteal Artery Aneurysm Repair and Therapy) registry.

METHODS AND RESULTS

A cluster analysis (using k-means clustering) was performed on data obtained from the multicenter POPART registry (42 centers from Germany and Luxembourg). Sensitivity analyses were conducted to explore validity and stability. Using 2 clusters, patients were primarily separated by the absence or presence of clinical symptoms. Within the cluster of symptomatic patients, the main difference between patients with acute limb ischemia presentation and nonemergency symptomatic patients was PAA diameter. When using 6 clusters, patients were primarily grouped by comorbidities, with patients with acute limb ischemia forming a separate cluster. Despite markedly different risk profiles, perioperative complication rates appeared to be positively associated with the proportion of emergency patients. However, clusters with a higher proportion of patients having any symptoms before treatment experienced a lower rate of perioperative complications.

CONCLUSIONS

The conducted analyses revealed both an insight to the public health reality of PAA care as well as patients with PAA at elevated risk for adverse outcomes. This analysis suggests that the preoperative clinic is a far more crucial adjunct to the patient's preoperative risk assessment than the patient's epidemiological profile by itself.

Bypass Patency and Amputation-Free Survival after Popliteal Aneurysm Exclusion Significantly Depends on Patient Age and Medical Complications: A Detailed Dual-Center Analysis of 395 Consecutive Elective and Emergency Procedures

Background/Objectives: A popliteal artery aneurysm (PAA) is traditionally treated by an open PAA repair (OPAR) with a popliteo-popliteal venous graft interposition. Although excellent outcomes have been reported in elective cases, the results are much worse in cases of emergency presentation or with the necessity of adjunct procedures. This study aimed to identify the risk factors that might decrease amputation-free survival (efficacy endpoint) and lower graft patency (technical endpoint). Patients and Methods: A dual-center retrospective analysis was performed from 2000 to 2021 covering all consecutive PAA repairs stratified for elective vs. emergency repair, considering the patient (i.e., age and comorbidities), PAA (i.e., diameter and tibial runoff vessels), and procedural characteristics (i.e., procedure time, material, and bypass configuration). Descriptive, univariate, and multivariate statistics were used. Results: In 316 patients (69.8 ± 10.5 years), 395 PAAs (mean diameter 31.9 ± 12.9 mm) were operated, 67 as an emergency procedure (6× rupture; 93.8% severe acute limb ischemia). The majority had OPAR (366 procedures). Emergency patients had worse pre- and postoperative tibial runoff, longer procedure times, and more complex reconstructions harboring a variety of adjunct procedures as well as more medical and surgical complications (all p < 0.001). Overall, the in-hospital major amputation rate and mortality rate were 3.6% and 0.8%, respectively. The median follow-up was 49 months. Five-year primary and secondary patency rates were 80% and 94.7%. Patency for venous grafts outperformed alloplastic and composite reconstructions (p < 0.001), but prolonged the average procedure time by 51.4 (24.3-78.6) min (p < 0.001). Amputation-free survival was significantly better after elective procedures (p < 0.001), but only during the early (in-hospital) phase. An increase in patient age and any medical complications were significant negative predictors, regardless of the aneurysm size. Conclusions: A popliteo-popliteal vein interposition remains the gold standard for treatment despite a probably longer procedure time for both elective and emergency PAA repairs. To determine the most effective treatment strategies for older and probably frailer patients, factors such as the aneurysm size and the patient's overall condition should be considered.

Sex disparities in popliteal artery aneurysms

OBJECTIVE

Only 5% of patients with popliteal artery aneurysms (PAAs) are female. Evidence on PAA treatment and outcomes in women is therefore scarce. The POPART Registry provides one of Europe's largest data collections regarding PAA treatment. Data on clinical presentation, aneurysm morphology, and perioperative outcomes after open surgical PAA repair in women will be presented.

METHODS

POPART is a multicenter, noninterventional registry for open and endovascular PAA repair, with 42 participating centers in Germany and Luxembourg. All patients aged >18 years who have been treated for PAA since 2010 are eligible for study inclusion. Data collection is based on an online electronic case report form.

RESULTS

Of the 1236 PAAs, 58 (4.8%) were in women. There were no significant differences in age or cardiopulmonary comorbidities. However, female patients had a lower prevalence of contralateral PAAs and abdominal aortic aneurysms (P < .05). PAAs in women were more likely to be symptomatic before surgery (65.5% vs 49.4%; P = .017), with 19% of women presenting with acute limb ischemia (vs 11%; P = .067). Women had smaller aneurysm diameters than men (22.5 mm vs 27 mm; P = .004) and became symptomatic at smaller diameters (20 mm vs 26 mm; P = .002). Only 8.6% of women and 11.6% of men underwent endovascular aneurysm repair (P > .05); therefore, the perioperative outcome analysis focused on open surgical repair. In total, 23.5% of women and 16.9% of men developed perioperative complications (P > .05). There were no differences in major cardiovascular events (P > .05), but women showed a higher incidence of impaired wound healing (15.7% vs 7.2%; P = .05) and major amputation (5.9% vs 1.1%; P = .027). Female sex was significantly associated with the need for nonvascular reinterventions within 30 days after surgery (odds ratio: 2.48, 95% confidence interval: 1.26-4.88), whereas no significant differences in the odds for vascular reinterventions were observed (odds ratio: 1.98, 95% confidence interval: 0.68-5.77). In the multiple logistic regression model, female sex, symptomatic PAAs, poor quality of outflow vessels, and graft material other than vein graft were independently associated with perioperative reinterventions.

CONCLUSIONS

Women have smaller PAAs, are more likely to be symptomatic before treatment, and are more often affected by nonvascular reinterventions in the perioperative course. As our understanding of aneurysmatic diseases in women continues to expand, sex-specific treatment strategies and screening options for women in well-selected cohorts with modified screening protocols should be continuously re-evaluated.

Endovascular Popliteal Artery Aneurysm Repair Using an "Off-Label" Abdominal Endograft Limb-Module with Nitinol-Ring Structure: A Single Centre Experience

PURPOSE

To evaluate endovascular popliteal artery aneurysm repair using a an "off-label" abdominal endograft limb-module with nitinol-ring structure.

MATERIALS AND METHODS

Retrospective observational study of 14 popliteal artery aneurysms in 12 male patients (mean age 76 years and median ASA grade 3) treated electively using the Anaconda™ endograft limb (Terumo Aortic) at a single teaching hospital. Eight limbs were treated percutaneously and 6 limbs required surgical arterial exposure. The mean popliteal artery aneurysm diameter treated was 3.6 cm (range 2.1-5.3 cm). Stent-graft diameters and lengths used were 10-15 and 60-140 mm, respectively. The median covered stented length was 218 mm (range 160-270 mm) and median duration of follow-up was 3.7 years. Outcomes assessed included technically successful aneurysm exclusion, primary patency, re-intervention and survival.

RESULTS

All patients had successful stent-graft deployment and aneurysm exclusion, with no early complications or mortality at 30 days. Primary stent-graft patency at 1, 3 and 4 years was 93%, 75%, and 64%. By 8 years, patency had declined with 29% (2/14) stent-grafts patent. 7/14 limbs occluded; 3 underwent re-intervention (2 surgical, 1 endovascular). There were no deaths related to the procedure. Freedom from re-intervention and survival at 1/5 years was 93%/84% and 93%/67%, respectively.

CONCLUSION

The Anaconda™ endograft limb for endovascular popliteal artery aneurysm repair offers good mid-term patency and acceptable long-term patency up to 4 years when compared with other grafts and open surgery. It may be considered in older comorbid patients unfit for surgery and can be performed percutaneously under local anaesthesia when anatomically feasible.

Focus on the Most Common Paucisymptomatic Vasculopathic Population, from Diagnosis to Secondary Prevention of Complications

Middle-aged adults can start to be affected by some arterial diseases (ADs), such as abdominal aortic or popliteal artery aneurysms, lower extremity arterial disease, internal carotid, or renal artery or subclavian artery stenosis. These vasculopathies are often asymptomatic or paucisymptomatic before manifesting themselves with dramatic complications. Therefore, early detection of ADs is fundamental to reduce the risk of major adverse cardiovascular and limb events. Furthermore, ADs carry a high correlation with silent coronary artery disease (CAD). This study focuses on the most common ADs, in the attempt to summarize some key points which should selectively drive screening. Since the human and economic possibilities to instrumentally screen wide populations is not evident, deep knowledge of semeiotics and careful anamnesis must play a central role in our daily activity as physicians. The presence of some risk factors for atherosclerosis, or an already known history of CAD, can raise the clinical suspicion of ADs after a careful clinical history and a deep physical examination. The clinical suspicion must then be confirmed by a first-level ultrasound investigation and, if so, adequate treatments can be adopted to prevent dreadful complications.

Apolipoprotein E (ApoE) Rescues the Contractile Smooth Muscle Cell Phenotype in Popliteal Artery Aneurysm Disease

Popliteal artery aneurysm (PAA) is the most frequent peripheral aneurysm, primarily seen in male smokers with a prevalence below 1%. This exploratory study aims to shed light on cellular mechanisms involved in PAA progression. Sixteen human PAA and eight non-aneurysmatic popliteal artery samples, partially from the same patients, were analyzed by immunohistochemistry, fluorescence imaging, Affymetrix mRNA expression profiling, qPCR and OLink proteomics, and compared to atherosclerotic (n = 6) and abdominal aortic aneurysm (AAA) tissue (n = 19). Additionally, primary cell culture of PAA-derived vascular smooth muscle cells (VSMC) was established for modulation and growth analysis. Compared to non-aneurysmatic popliteal arteries, VSMCs lose the contractile phenotype and the cell proliferation rate increases significantly in PAA. Array analysis identified APOE higher expressed in PAA samples, co-localizing with VSMCs. APOE stimulation of primary human PAA VSMCs significantly reduced cell proliferation. Accordingly, contractile VSMC markers were significantly upregulated. A single case of osseous mechanically induced PAA with a non-diseased VSMC profile emphasizes these findings. Carefully concluded, PAA pathogenesis shows similar features to AAA, yet the mechanisms involved might differ. APOE is specifically higher expressed in PAA tissue and could be involved in VSMC phenotype rescue.

Abdominal aortic aneurysm presenting to the orthopedic clinic as posterior hip and low back pain

Abdominal aortic aneurysms (AAAs) are typically asymptomatic. When symptomatic, AAA may present as a chief concern of musculoskeletal hip and low back pain. Assessment in the orthopedic clinic should focus on a holistic examination of the patient.

Reporting lower extremity CT angiography for treatment planning

Diagnostic radiologists play an important role in the evaluation of patients presenting with signs and symptoms of lower extremity peripheral vascular disease, including critical limb ischemia in both acute and chronic settings, and intermittent claudication. The complications associated with tissue and/or limb loss related to acute limb ischemia and critical limb ischemia of the lower extremity make rapid diagnosis and early intervention critical in the management of these patients. Computed tomography angiography (CTA) is an effective, widely available, easily reproducible, non-invasive imaging modality that offers a rapid and accurate means to diagnose and grade the extent of vascular disease. However, CTA run-off reports are usually dictated in free text form, and referring and treating physicians may be unsure whether an anatomic structure has been evaluated if it has not been specifically mentioned in the report. In this article, the vascular anatomy and anatomic variants of the lower extremity, the most common lower extremity vascular pathologies are reviewed and clinically important CTA imaging findings are outlined. This provides a framework for radiologists to accurately evaluate lower extremity vascular pathologies and convey clinically relevant imaging findings for management by vascular surgeons or interventional radiologists.

Natural history, growth rates, and treatment of popliteal artery aneurysms

BACKGROUND

The natural history of a cohort of patients monitored for popliteal artery aneurysms (PAAs) has not been well described. A prevailing uncertainty exists regarding the optimal surveillance strategies and timing of treatment. The primary aim of the present study was to describe the care trajectory of all patients with PAAs identified at two tertiary vascular centers, both in surveillance and eventually treated. The secondary aim was to define the PAA growth rates.

METHODS

A retrospective, multicenter cohort study was performed of all patients with PAAs at two vascular centers in two countries (Sweden, 2009-2016; New Zealand, 2009-2017). Data were collected from electronic medical records regarding the comorbidities, treatment, and outcomes and analyzed on a patient- and extremity-specific level. Treatment was indicated at the occurrence of emergent symptoms or considered at a PAA threshold of >2 cm. The PAAs were divided into small (≤15 mm) and large (>15 mm) aneurysms. The mean surveillance follow-up was 5.1 years.

RESULTS

Most of the 241 identified patients (397 limbs) with a diagnosis of PAAs had bilateral aneurysms (n = 156). Most patients were treated within the study period (163 of 241; 68%), and one half of the diagnosed extremities with PAA had been treated (54%; 215 of 397). Among those who had undergone elective repair, treatment had usually occurred within 1 year after the diagnosis (66%; 105 of 158). More small PAAs were detected in the group that had required emergent repair compared with elective repair (6 of 57 [11%] vs 12 of 158 [8%]; P < .001). No differences were found in the mean diameters between the elective and emergent groups (30.1 mm vs 32.2 mm; P = .39). Growth was recorded in 110 PAAs and on multivariate analysis was associated with a larger index diameter (odds ratio, 1.138; 95% confidence interval, 1.040-1.246; P = .005) and a concurrent abdominal aortic aneurysm (odds ratio, 2.553; 95% confidence interval, 1.018-6.402; P = .046).

CONCLUSIONS

The present cohort of patients represented a true contemporary clinical setting of monitored PAAs and showed that most of these patients will require elective repair, usually within 1 year. The risk of emergent repair is not negligible for patients with smaller diameter PAAs. However, the optimal selection strategy for preventive early repair is still unknown. Future morphologic studies are needed to support the development of individualized surveillance protocols.

The Society for Vascular Surgery clinical practice guidelines on popliteal artery aneurysms

The Society for Vascular Surgery clinical practice guidelines on popliteal artery aneurysms (PAAs) leverage the work of a panel of experts chosen by the Society for Vascular Surgery to review the current world literature as it applies to PAAs to extract the most salient, evidence-based recommendations for the treatment of these patients. These guidelines focus on PAA screening, indications for intervention, choice of repair strategy, management of asymptomatic and symptomatic PAAs (including those presenting with acute limb ischemia), and follow-up of both untreated and treated PAAs. They offer long-awaited evidence-based recommendations for physicians taking care of these patients.

Systematic Review of the Co-Prevalence of Arterial Aneurysms Within the Vasculature

OBJECTIVE

Aneurysms are considered focal manifestations of a systemic vascular condition, and various studies report co-prevalence of aneurysms in different vascular beds. Insight into profiles of patients at risk of multiple aneurysms is lacking, and few clinical algorithms exist if additional screening is indicated. This systematic review assessed the co-prevalence of aneurysms in different vascular beds and analysed putative risk factors for multiple aneurysms.

METHODS

Medline, Embase, and Cochrane libraries were searched up to February 2020 for studies reporting co-prevalence of aneurysms in different vascular beds using the keywords: "aneurysm", "co-prevalence", or synonyms. All studies were reviewed by two authors independently. Studies were excluded if they described concomitant treatment of multi-aneurysms, or if the aneurysm was reported solely bilateral, post-dissection, mycotic, traumatic, iatrogenic, or caused by a connective tissue disease. Radar plots were used to indicate studies that found an association between the investigated features and aneurysm co-prevalence against those that did not.

RESULTS

Thirty-two studies met the inclusion criteria, describing in total 16 353 patients of whom 2 015 had at least one additional aneurysm. The weighted co-prevalence was 16.9% (95% confidence interval [CI] 11.8-22.6), I² > 90%. At least 19 combinations of aneurysms were described, mostly derived from retrospective studies. Seventeen of 32 (53%) studies described concurrent aneurysms in patients with an abdominal aortic aneurysm. Predominantly positive associations were found for higher age, hypertension, stenotic disease, presence of multiple (at least three) aneurysms, and primary aneurysm size.

CONCLUSION

Approximately one in six patients with a primary aneurysm harbours an additional aneurysm, increasing to one in four if the patient has a popliteal artery aneurysm. Higher age, hypertension, stenotic disease, presence of multiple (at least three) aneurysms, and primary aneurysm size were predictive of aneurysm co-prevalence. These clinical predictors may assist when deciding whether a patient with a primary aneurysm needs to be screened for additional aneurysms.

Lower extremity arteries

Lower extremity arteries play vital role of supplying blood to the extremity bone, muscles, tendons and nerves to maintain the mobility of the body. These arteries may get involved with a number of disease processes which restrict the optimal functioning of the limb. The knowledge of various diseases, clinical presentation, appearance on various imaging modalities and segments of involvement helps one to clinch the diagnosis. It is of paramount importance for imaging clinician to apply the correct imaging tool based on the clinical question which is facilitated by know how of the advantages and limitation of each of these imaging modalities. This article focuses on lower extremity arteries, its anatomy, various imaging modalities and common disease conditions affecting the lower limb arteries.

In Vivo Morphological Changes of the Femoropopliteal Arteries due to Knee Flexion After Endovascular Treatment of Popliteal Aneurysm

Purpose: To evaluate morphological changes of the femoropopliteal (FP) arteries due to limb flexion in patients undergoing endovascular treatment of popliteal artery aneurysms (PAAs). Materials and Methods: Seven male patients (mean age 68 years) underwent endovascular treatment of PAA with a Viabahn stent-graft between January 2013 and December 2017. During follow-up, one contrast-enhanced computed tomography angiography (CTA) scan of the lower limbs was acquired for each recruited patient. A standardized CTA protocol for acquisitions in both straight-leg and bent-leg positions was used to visualize changes in artery shape due to limb flexion. Three-dimensional reconstruction of the FP segment was performed to compute mean diameter and eccentricity of the vascular lumen and to measure length, tortuosity, and curvature of the vessel centerline in 3 arterial zones: (A) between the origin of the superficial femoral artery and the proximal end of the stent-graft, (B) within the stent-graft, and (C) from the distal end of the stent-graft to the origin of the anterior tibial artery. Results: After limb flexion, all zones of the FP segment foreshortened: 6% in zone A (p=0.001), 4% in zone B (p=0.001), and 8% in zone C (p=0.07), which was the shortest (mean 4.5±3.6 cm compared with 23.8±5.7 cm in zone A and 23.6±7.4 cm in zone B). Tortuosity increased in zone A (mean 0.03 to 0.05, p=0.03), in zone B (0.06 to 0.15, p=0.005), and in zone C (0.027 to 0.031, p=0.1). Mean curvature increased 15% (p=0.05) in zone A, 27% (p=0.005) in zone B, and 95% (p=0.06) in zone C. In all zones, the mean artery diameter and eccentricity were not significantly affected by limb flexion. Conclusion: Limb flexion induces vessel foreshortening and increases mean curvature and tortuosity of the FP segment both within and outside the area of the stent-graft.

Popliteal Artery Entrapment Syndrome (PAES) in a 17-Year-Old Adolescent

Introduction

Popliteal artery entrapment syndrome (PAES) is caused by compression of the popliteal artery (PA) due to deranged myotendinous structures. It can be asymptomatic or may present with exercise intolerance, claudication, or even limb-threatening ischemia. The clinical picture depends on the anatomy and degree of vascular compromise.

Case Description

We report a case of a 17-year-old Caucasian male with PAES Type II presenting with intermittent claudication and progression towards acute limb ischemia.

Diagnostics

MRI and MRA helped identifying the aberrant anatomy and thrombotic occlusion. Doppler ultrasound and conventional angiography have also been employed in a stepwise approach.

Intervention

The thrombus at the site of occlusion was removed by the use of catheter-directed lysis. Subsequently, popliteal artery release was achieved by myotomy of the aberrant medial head of gastrocnemius muscle (MHGM) and muscle transfer to the medial femoral condyle. A three-month regimen of 60mg edoxaban was recommended after surgery.

Outcome

Surgical correction of the anomalous anatomy and postoperative anticoagulation led to freedom of symptoms.

Lesson

Clinical presentation of PAES mimicking peripheral artery occlusive disease is very rare but potentially limb-threatening. PAES should be considered in young and otherwise healthy individuals.

Prevalence of Synchronous and Metachronous Aneurysms in Women With Abdominal Aortic Aneurysm

BACKGROUND

Abdominal aortic aneurysm (AAA) is three to five times more common among men compared with women, yet up to 38% of all aneurysm related deaths affect women. The aim of this study was to estimate the prevalence of synchronous or metachronous aneurysms among women with AAA, as diagnosis and treatment could improve survival.

PATIENTS AND METHODS

This is a retrospective study of prospectively registered patients. All women operated on, or under surveillance for, AAA were identified at two Swedish hospitals. Aneurysms in different locations were identified using available imaging studies. Aneurysms were defined according to location: thoracic ascending aorta ≥42 mm, descending ≥33 mm, abdominal aorta ≥30 mm, common iliac artery ≥20 mm or 50% wider than the contralateral artery, common femoral artery ≥12 mm, popliteal artery ≥10 mm.

RESULTS

A total of 339 women with an AAA were included. The median follow up was 2.8 (range 0-15.7) years. Thirty-one per cent had an aneurysm in the thoracic aorta (67 of 217 investigated, 84% were located in the descending aorta), 13 (19%) underwent repair. Twelve per cent had a common iliac artery aneurysm (24/259, 76% were investigated). Common femoral artery aneurysms were identified in 4.3% (8/184, 54% investigated). Popliteal artery aneurysms were identified in 4.0% (6/149, 44% investigated). The prevalence of infrainguinal aneurysms was higher among patients with synchronous iliac aneurysms (40% vs. 1.6%, OR 42, 95% CI 6.4-279, p < .001).

CONCLUSIONS

Thoracic aortic aneurysms are common among women with AAA, most commonly affecting the descending aorta, and detection frequently results in repair. Popliteal and femoral aneurysms are not rare among women with AAA, and even common if there is a synchronous iliac aneurysm.

Increasing the Elective Endovascular to Open Repair Ratio of Popliteal Artery Aneurysm

Background:

Open repair (OR) for popliteal artery aneurysm (PAA) has recently been challenged by endovascular repair (ER) as the primary choice of treatment. The aim of the present study was to evaluate time trends in treatment modality and compare outcomes between OR and ER among electively operated patients after start of screening in 2010 for abdominal aortic aneurysm (AAA), a disease highly associated with PAA.

Methods:

Between January 1, 2009, and April 30, 2017, 102 procedures and 36 acute and 66 elective repairs for PAA were identified.

Results:

Over time, a trend ( P = .089) for an increasing elective to acute repair ratio of PAA and an increase in elective ER to OR ratio ( P = .003) was found. Among electively repaired PAAs, the ER group was older ( P = .047) and had a higher ankle–brachial index (ABI; P = .044). The ER group had fewer wound infections ( P = .003), fewer major bleeding complications ( P = .046), and shorter in-hospital stay ( P < .001). After 1 year of follow-up, the ER group had a higher rate of major amputations ( P = .037). Amputation-free survival at the end of follow-up did not differ between groups ( P = .68). Among the 17 patients with PAA eligible for AAA screening, 4 (24%) were diagnosed with PAA through the screening program of AAA.

Conclusion:

The epidemiology of elective repair of PAA has changed toward increased ER, although ER showed a higher rate of major amputations at 1 year. Confounding was considerable and a randomized trial is needed for evaluation of the best therapeutic option.

Vessel wall morphology is equivalent for different artery types and localizations of advanced human aneurysms

Aneurysm formation occurs most frequently as abdominal aortic aneurysm (AAA), but is also seen in other localizations like thoracic or peripheral aneurysm. While initial mechanisms for aneurysm induction remain elusive, observations from AAA samples show transmural inflammation with proteolytic imbalance and repair mechanisms triggered by the innate immune system. However, limited knowledge exists about aneurysm pathology, especially for others than AAA. We compared 42 AAA, 15 popliteal, 3 ascending aortic, five iliac, two femoral, two brachial, one visceral and two secondary aneurysms to non-aneurysmatic controls by histologic analysis, immunohistochemistry and cytokine expression. Muscular and elastic type arteries show a uniform way of aneurysm formation. All samples show similar morphology. The changes compared to controls are distinct and include matrix remodeling with smooth muscle cell phenotype switch and angiogenesis, adventitial lymphoid cell accumulation and M1 macrophage homing together with neutrophil inflammation. Inflammatory cytokines are up-regulated accordingly. Comparative analysis of different disease entities can identify characteristic pathomechanisms. The phenotype of human advanced aneurysm disease is observed for elastic and muscular type arteries, does not differ between disease localizations and might, thus, be a unique response of the vasculature to the still unknown trigger of aneurysm formation.

Uncommon Diseases of The Popliteal Artery: A Pictorial Review

Uncommon diseases of the popliteal artery include cystic adventitial disease, popliteal artery entrapment syndrome (PAES) and popliteal artery aneurysm (PAA). Because all of these conditions may present with pain or intermittent claudication, imaging is crucial for differentiating them and directing management. Delayed diagnosis can lead to major complications, including acute limb ischemia. Our aim is to provide an illustrative overview of these conditions in order to make radiologists aware of them and avoid misdiagnosis for timely appropriate management.

Teaching Points

• Cystic adventitial disease diagnosis is based on evidence of cysts within artery walls.

• A variety of anatomic variations may result in PAES.

• PAES may be bilateral.

• PAA is most commonly encountered in men.

• Acute complications of PAA include acute thrombosis and distal embolization.