Arterial injuries: a sonographic approach

Clinical Features and Endovascular Management of Iliac Arteriovenous Fistulas: A 10-Year Single Center Experience

Objective

Iliac arteriovenous fistulas (IAVFs) are rare abnormalities with limited reported cases. This study aimed to summarize the clinical features and experiences on the diagnosis and endovascular treatment of IAVFs.

Methods

A single-center retrospective study of IAVFs from 2010 to 2019 was performed. Data including demographics, clinical characteristics, radiological images, surgical details, and follow-up were collected.

Results

A total of 16 patients diagnosed with IAVFs were identified. The female to male ratio was 3:1. The mean age was 47.7 ± 10.4 years (range: 35–73 years). Leg swelling and cardiac insufficiency, especially heart failure, were the most common primary symptoms in this series, which were revealed in 68.8 and 37.5% of patients, respectively. Iatrogenic, traumatic, and congenital IAVFs were diagnosed in 62.5, 12.5, and 25.0% of patients, respectively, among which hysterectomy was thought to be the main cause for female iatrogenic IAVFs (31.3%). Anatomic analysis found that internal iliac vessels were the predilected sites of IAVFs. All the patients were treated by endovascular procedures composed of transarterial embolization (50.0%), transarterial and stage II transvenous embolization (31.3%), stage I transarterial and transvenous embolization (12.5%), and transarterial embolization plus stent implantation (6.3%). The clinical success rate was 93.8%. Minor complications including fever (18.8%) and exudation at the puncture point (6.25%) were noted and well-treated. During a follow-up period of 51.3 ± 41.9 months after operations, only one patient experienced re-emergence of heart failure because of recurrence of leiomyosarcoma; other patients recovered uneventfully with symptoms relief and no severe embolization-related complications was encountered.

Conclusion

IAVFs are rare disorders and correct diagnosis requires careful history taking and physical examination, combined with proper imaging investigation. The primary goal for treatment of IAVFs was to relieve associated symptoms. Based on the results of this study, endovascular approach is safe and effective for treatment of IAVFs.

A Rare Cause of Post-traumatic Right Lower Extremity Swelling in an Adolescent Male

Unilateral extremity swelling after trauma usually results from acute musculoskeletal or orthopedic injuries. Worsening of swelling raises concern for compartment syndrome or vascular injury. Time-sensitive diagnosis and interventions are needed to avoid life- or limb-threatening consequences. In this report, we highlight the case of a 16-year-old male who presented with unilateral lower extremity pain and swelling, one week after a motor vehicle accident. Thorough evaluation and appropriate imaging detected the presence of an abnormal communication between the muscular branch of the anterior tibial artery and the vein. Arteriovenous fistulas (AVFs) are usually acquired and caused by penetrating trauma or iatrogenic procedures. They are rarely associated with blunt trauma. It is important to determine the degree of flow within the communication, as high flow lesions are associated with severe complications such as limb ischemia and heart failure. This report highlights the evaluation and management of a patient with delayed post-traumatic unilateral extremity swelling that eventually resulted in the diagnosis of a low-flow AVF amenable to conservative management, resulting in complete resolution of his symptoms.

A dual-plane approach for surgical treatment of pseudoaneurysm with arteriovenous fistula in hemodialysis patients

Background

We report the efficacy of a dual-plane approach using a Dufourmentel skin flap with a purse-string suture of the de-epithelized dermis to manage pseudoaneurysm at the vascular access site for hemodialysis.

Methods

A retrospective analysis was conducted of 61 patients from 2013 to 2018 with pseudoaneurysms at the arteriovenous fistula or graft who were treated with rhomboid excision, vessel repair with a purse-string suture, and a full-thickness Dufourmentel skin flap. The success rate was defined as the probability of complete wound closure and intact vascular access patency without infection or other complications.

Results

The success rate was 93.4% at 6 months postoperatively. Complications included newly occurring pseudoaneurysms (n=2), wound dehiscence (n=1) and bleeding (n=1). There were no complications such as stenosis or thrombosis from the procedure.

Conclusions

A dual-plane approach using a Dufourmentel skin flap with a purse-string suture for vessel repair was shown to be a favorable option for managing stable, small (diameter <2 cm) pseudoaneurysms without infection, rapid expansion, or patency issues of the vascular access.

Emergency color Doppler sonography of the extremity artery: A pictorial essay

Arterial color duplex sonography (CDUS) of the extremities is routinely analyzed in the field of emergency radiology. A retrospective review of 500 consecutive arterial CDUS extremity studies was performed in our emergency department. Abnormal CDUS examinations were classified into two groups according to their primary etiology: 1) traumatic arterial injuries (accidents or post-operative complications) and 2) acute arterial ischemia (thrombosis or embolism outside of the setting of acute trauma). This article reviews common CDUS imaging findings in a busy emergency radiology division including traumatic pseudoaneurysm, secondary pseudoaneurysm, arteriovenous fistula, acute ischemic arterial disease and chronic peripheral arterial disease. This essay highlights the crucial role of CDUS in the diagnosis of vascular abnormalities in the emergency setting. CDUS provides several advantages over other imaging modalities including high accuracy, rapid results, portability, lack of radiation, and low cost.

"To-and-fro" waveform in the diagnosis of arterial pseudoaneurysms

Medical ultrasound imaging with Doppler plays an essential role in the diagnosis of vascular disease. This study intended to review the clinical use of “to-and-fro” waveform at duplex Doppler ultrasonography (DDU) in the diagnosis of pseudoaneurysms in the arterial vessels of upper and lower extremities, abdominal aorta, carotid and vertebral arteries as well as to review our personal experiences of “to-and-fro” waveform at DDU also. After receiving institutional review board approval, an inclusive literature review was carried out in order to review the scientific foundation of “to-and-fro” waveform at DDU and its clinical use in the diagnosis of pseudoaneurysms in various arterial vessels. Articles published in the English language between 2000 and 2013 were evaluated in this review study. Pseudoaneurysms in arterial vessels of the upper and lower extremities, abdominal aorta, carotid and vertebral arteries characterized by an extraluminal pattern of blood flow, which shows variable echogenicity, interval complexity, and “to-and-fro” flow pattern on color Doppler ultrasonography. In these arterial vessels, Duplex ultrasonography can demonstrate the degree of clotting, pseudoaneurysm communication, the blood flow patterns and velocities. Spectral Doppler applied to pseudoaneurysms lumen revealed systolic and diastolic turbulent blood flow with traditional “to-and-fro” waveform in the communicating channel. Accurate diagnosis of pseudoaneurysm by spectral Doppler is based on the documentation of the “to-and-fro” waveform. The size of pseudoaneurysm determines the appropriate treatment approach as surgical or conservative.

Physical exam myths: listening for carotid artery bruits in stroke patients

When a patient presents to the emergency department with a neurologic deficit and a cerebrovascular event is included in the differential diagnosis, the classic recommendation is to examine the carotid artery and assess for the presence of a bruit. The diagnostic yield and utility of this practice has seldom been called into question. This critical appraisal will review the practice of listening for a carotid artery bruit (CAB) in suspected stroke patients and analyze its clinical utility, including the sensitivity and specificity of a CAB for detecting a significant lesion and the potential impact a CAB may have on the investigation and disposition of such patients.

A novel decision tree approach based on transcranial Doppler sonography to screen for blunt cervical vascular injuries

OBJECTIVES

Early detection and treatment of blunt cervical vascular injuries prevent adverse neurologic sequelae. Current screening criteria can miss up to 22% of these injuries. The study objective was to investigate bedside transcranial Doppler sonography for detecting blunt cervical vascular injuries in trauma patients using a novel decision tree approach.

METHODS

This prospective pilot study was conducted at a level I trauma center. Patients undergoing computed tomographic angiography for suspected blunt cervical vascular injuries were studied with transcranial Doppler sonography. Extracranial and intracranial vasculatures were examined with a portable power M-mode transcranial Doppler unit. The middle cerebral artery mean flow velocity, pulsatility index, and their asymmetries were used to quantify flow patterns and develop an injury decision tree screening protocol. Student t tests validated associations between injuries and transcranial Doppler predictive measures.

RESULTS

We evaluated 27 trauma patients with 13 injuries. Single vertebral artery injuries were most common (38.5%), followed by single internal carotid artery injuries (30%). Compared to patients without injuries, mean flow velocity asymmetry was higher for single internal carotid artery (P = .003) and single vertebral artery (P = .004) injuries. Similarly, pulsatility index asymmetry was higher in single internal carotid artery (P = .015) and single vertebral artery (P = .042) injuries, whereas the lowest pulsatility index was elevated for bilateral vertebral artery injuries (P = .006). The decision tree yielded 92% specificity, 93% sensitivity, and 93% correct classifications.

CONCLUSIONS

In this pilot feasibility study, transcranial Doppler measures were significantly associated with the blunt cervical vascular injury status, suggesting that transcranial Doppler sonography might be a viable bedside screening tool for trauma. Patient-specific hemodynamic information from transcranial Doppler assessment has the potential to alter patient care pathways to improve outcomes.

Emergency bedside sonographic diagnosis of subclavian artery pseudoaneurysm with brachial plexopathy after clavicle fracture

Clavicle fractures are common; however, complications are unusual. Two such complications, subclavian artery pseudoaneurysm and brachial plexopathy, are rare events that can cause significant morbidity and mortality. We report the case of a 53-year-old man who presented with shoulder swelling and right arm weakness for 1 week. Three weeks before, he had fallen and fractured his right clavicle. On presentation to our emergency department, his examination revealed a brachial plexopathy and a large supraclavicular mass. An emergency bedside triplex sonogram was performed to characterize the mass and revealed a swirling pattern within a fluid collection anterior to the subclavian artery, suggestive of a pseudoaneurysm. After computed tomography-angiography, the patient was taken to the operating room, where he underwent hematoma washout and subclavian artery stent-graft placement. This case illustrates how bedside point-of-care sonography can rapidly assist in the initial assessment of subclavian artery injury.

Spontaneous internal carotid artery pseudoaneurysm in a patient with behçet disease

We describe the uncommon case of a patient with Behçet disease who developed a giant spontaneous cervical internal carotid artery pseudoaneurysm confirmed at surgery. We also discuss the implications of this rare complication.

Traumatic brachial artery pseudoaneurysm diagnosed in the emergency department with point-of-care bedside ultrasound

Case

A 55-year-old gentleman was referred to the emergency department for penetrating trauma of his left upper arm. X-rays identified a metallic foreign body. Clinical examination revealed a swollen left upper arm with a pulsatile mass. Point-of-care bedside ultrasound in the ED confirmed a traumatic brachial artery pseudoaneurysm.

Discussion

The features of a peripheral pseudoaneurysm and its ultrasonographic appearance in both B-mode, and color Doppler imaging.

Sonographic evaluation of vascular injuries

OBJECTIVE

The purpose of this presentation is to highlight the color Doppler duplex sonographic features of procedure-related and blunt or penetrating trauma-related vascular injuries.

METHODS

Different kinds of vascular complications such as pseudoaneurysms, arteriovenous fistulas, dissection, and thrombosis are discussed. Cases of vascular injuries in the extremities, neck, and abdomen are presented to illustrate the spectrum of sonographic appearances.

RESULTS

Color Doppler duplex sonography is valuable in the diagnosis and monitoring of most vessel injuries and in the treatment of pseudoaneurysms. It is useful for flow analysis and for follow-up after treatment. However, because of limitations inherent to sonography, such as bones, air, casts, skin burns, and relatively slow performance of the test, magnetic resonance imaging, computed tomography, and angiography are necessary for further evaluation in selected cases.

CONCLUSIONS

Color Doppler duplex sonography is a widely available, noninvasive, and accurate technique for evaluating vascular injuries and should be the first-line imaging modality in most patients.

Pulsatile flow phantom for ultrasound image-guided HIFU treatment of vascular injuries

A pulsatile flow phantom was developed for studies of ultrasound image-guided high intensity focused ultrasound (HIFU) application in transcutaneous hemostasis of injured blood vessels. The flow phantom consisted of a pulsatile pump system with instrumented excised porcine carotid artery, which was imbedded in a transparent agarose gel to model structural configuration of in vivo tissues. Heparinized porcine blood was circulated through the phantom. The artery was injured using an 18-gauge needle to model a penetrating injury in human peripheral vasculature. A HIFU transducer with the diameter of 7 cm, focal length of 6.3 cm and frequency of 3.4 MHz was used to seal the puncture. Ultrasound imaging was used to localize and target the puncture site and to monitor the HIFU treatment. Triphasic blood flows present in the human arteries were reproduced, with flow rates of 50 to 500 mL/min, pulse rates of 62 to 138 beats/min and peak pressures of 100 to 250 mm Hg. The penetrating injury of an artery was mimicked successfully in the flow phantom setting and was easily visualized both optically through the transparent gel and with power Doppler ultrasound imaging. Hemostasis was achieved in 55 +/- 31 s (n = 9) of HIFU application. Histologic observations showed that a HIFU-sealed puncture was filled with clotted blood and covered with a fibrin cap. The pulsatile flow phantom provides a controlled and repeatable environment for studies of transcutaneous image-guided HIFU application in hemostasis of a variety of blood vessel injuries.

Ultrasonic interrogation of tissue vibrations in arterial and organ injuries: preliminary in vivo results

Soft tissues surrounding vascular injuries are known to vibrate at audible and palpable frequencies, producing bruits and thrills. We report the results of a feasibility study where Doppler ultrasound (US) was used to quantitatively estimate the tissue vibrations after induced trauma in an animal model. A software-programmable US system was used to acquire quadrature-demodulated ensembles of received US echoes bypassing clutter filtering and other conventional Doppler processing stages. The waveforms of tissue velocity surrounding the injury site were then estimated from the clutter data using autocorrelation and analyzed to determine vibration characteristics. Six New Zealand white rabbits and two juvenile pigs were used for the study. The femoral artery of the anesthetized animal was punctured with an 18-gauge needle to model a peripheral arterial trauma, and the liver was surgically exposed and incised to model organ trauma. Two types of oscillatory tissue motion were observed: "vibrations" with high frequency (>50 Hz) and low peak-peak amplitude (<1 microm) and "flutter" with low frequency (<50 Hz) and high peak-peak amplitude (>1 microm). Active bleeding in femoral artery punctures produced tissue vibrations at the frequency of 323 +/- 214 Hz (mean +/- standard deviation, pooled for both rabbits and pigs) and the amplitude of 0.24 +/- 0.15 microm. Active bleeding in liver incisions produced vibrations at the frequency of 120 +/- 47 Hz and the amplitude of 0.33 +/- 0.25 microm. Flutter was observed in punctured arteries at the frequency of 28 +/- 13 Hz the amplitude of 2.92 +/- 1.75 microm, and in incised livers at the frequency of 26 +/- 6 Hz and the amplitude of 1.53 +/- 0.76 microm. In a punctured artery, the vibration frequency and phase of tissue surrounding the artery were highly correlated between neighboring locations in tissue (correlation coefficient = 0.98), and with the flow oscillations in the lumen (correlation coefficient = 0.96). This preliminary study indicates that tissue vibrations could provide additional physiologic information for detecting, localizing and monitoring internal bleeding using US.