Interpretation of upper extremity arteriography: vascular anatomy and pathology [corrected]

Super Selective Embolization and Immediate Resection of a High-flow Arteriovenous Malformation in the Hand

A significant proportion of high-flow arteriovenous malformations (AVMs) in the hand are complex to treat due to their multicentricity, size, and risk of jeopardizing distal circulation. Therefore, AVMs are frequently considered "inoperable." We present the case of a multifocal recurrent AVM treated in conjunction with the interventional radiology department, with intra-arterial embolization and excision followed by immediate distal revascularization to replace the resulting arterial deficit. This is a case of a 24-year-old woman with a high-flow multifocal AVM in her right hand, partially excised 2 years ago, showing a pulsatile mass in the palm and dorsum of the right hand, and a reporting pain of 8 of 10 on the visual analogue scale. The procedure was performed in our hybrid operating room. This procedure lasted 4 hours, with intraoperative bleeding of 75 mL. Three weeks after the procedure, patency and good circulation of the three revascularized fingers was demonstrated using arteriography and no evidence of vascular anomalies were found. No skin loss occurred, and no reintervention was required. For radical excision of this complex high-flow recurrent AVM, detailed intraoperative documentation of its afferent and immediate embolization with gelatin-based hemostatic agents allowed its obliteration with a low reactive material. We consider that this approach might be an option to treat AVMs that are currently considered inoperable.

Magnetic Resonance Angiography of the Hand Vasculature in Patients With Systemic Sclerosis and Systemic Lupus Erythematosus

BACKGROUND

When patients with systemic sclerosis (SSc) and systemic lupus erythematosus (SLE) develop digital ischemia, conventional angiography (CA) is traditionally used to assess hand vasculature. Recently, Chang et al described an angiographic classification system for patients with SSc. Conventional angiography uses intravascular contrast agents that are nephrotoxic and vasoconstrictive. Owing to these limitations, this study assesses the use of contrast-enhanced magnetic resonance angiography (MRA) as an alternative to CA to evaluate hand vasculature in patients with digital ischemia.

METHODS

This retrospective case series reports on 38 contrast-enhanced MRAs of hand vasculature from 30 symptomatic patients with SSc (N = 21) or SLE (N = 9). The radial and ulnar arteries (RA, UA) and the superficial and deep palmar arches were evaluated at standard reference points both quantitatively and qualitatively for their diameter, patency, and Chang classification.

RESULTS

In SSc MRAs (n = 26), the UA was significantly smaller than the RA and was occluded in 46%. In SLE MRAs (n = 12), the UA and RA had no difference in diameter and the UA was occluded in 25%. In SSc, the most common Chang classification was type 2 (UA involvement) in 44%. In SLE, the most common Chang classification was type 4 (UA and RA involvement) in 45%, with 18% classified as type 2.

CONCLUSIONS

Contrast-enhanced MRA used to assess hand vasculature in SSc patients with digital ischemia shows similar patterns of vascular involvement as previously demonstrated by CA. While vascular involvement in SSc predominantly involves the UA, the RA is also frequently involved in SLE.

Acute ischemia of the upper and lower limbs: Tailoring the treatment to the underlying etiology

Acute limb ischemia (ALI) can be a devastating clinical emergency with potentially limb- or life-threatening consequences. It is defined as a quickly developing or sudden decrease in limb perfusion producing new or worsening symptoms and signs, often threatening limb viability. ALI is commonly related to an acute arterial occlusion. Rarely, extensive venous occlusion can lead to upper and lower extremities ischemia (ie, phlegmasia). The incidence of acute peripheral arterial occlusion causing ALI is approximately 1.5 cases per 10,000 people per year. The clinical presentation depends on the etiology and whether the patient has underlying peripheral artery disease. Except for traumas, the most common etiologies are embolic or thrombotic events. Peripheral embolism, likely related to embolic heart disease, is the most common cause of acute upper extremity ischemia. However, an acute thrombotic event may occur in native arteries, at the site of a pre-existing atherosclerotic plaque, or as a failure of previous vascular interventions. The presence of an aneurysm may predispose to ALI for both embolic and thrombotic mechanisms. Immediate diagnosis, accurate assessment of limb viability, and prompt intervention, when needed, play important roles in salvaging the affected limb and preventing major amputation. Severity of symptoms is usually dependent on the amount of surrounding arterial collateralization, which may often reflect a pre-existing chronic vascular disease. For this reason, early recognition of the underlying etiology is crucial for choice of best management and definitely for treatment success. Any error in the initial evaluation may negatively affect the functional prognosis of the limb and endanger the patient's life. The aim of this article was to discuss diagnosis, etiology, pathophysiology, and treatment of patients with acute ischemia of the upper and lower limbs.

Traumatic arterial injuries in upper and lower limbs: what every radiologist should know

Traumatic arterial injuries of the extremities are a rare but potentially fatal event. Computed tomography (CT) angiography of the extremities has become the technique of choice and can provide rapid accurate detection and characterization of vascular lesions. Vascular injuries can be classified in active hemorrhage, vasospasm, occlusion, post-traumatic arteriovenous fistula, pseudoaneurysm, and patterns of intimal injuries. The learning objectives of this pictorial essay are to review the normal arterial anatomy of the upper and lower limbs, describe the technique of CT angiography in vascular trauma of the extremities, describe and illustrate the CT-angiography findings of traumatic arterial injuries, and know the potential pitfalls when interpreting a CT-angiography of the extremities.

Upper Extremity Angiographic Patterns in Systemic Sclerosis: Implications for Surgical Treatment

PURPOSE

Conventional angiography is often used in the preoperative work-up of hand surgery patients with systemic sclerosis. The goal of this study was to propose a classification system based on the pattern of arterial involvement in a series of upper extremity angiograms. The authors hypothesized that this classification system would demonstrate high inter- and intrarater reliability.

METHODS

A retrospective review of 110 upper extremity angiograms in patients with systemic sclerosis (obtained between 1996 and 2017) was performed. Images were classified into 4 types based on the patency of the radial and ulnar arteries at the wrist, and into 3 subtypes based on the patency of the superficial and deep palmar arches. Classification reliability was compared with Fleiss' Kappa (for inter-rater) and Cohen's (for intrarater) coefficient between 4 fellowship-trained hand surgeons and a hand fellow.

RESULTS

The inter-rater reliability between all 5 observers using types alone was 0.83 (0.80-0.85), whereas the inter-rater reliability using subtypes was 0.64 (confidence interval [CI] 95%, 0.62-0.65). The intrarater reliability using types alone ranged from 0.80 to 0.95, whereas intrarater reliabilities using subtypes were 0.81 (CI 95%, 0.72-0.90), 0.78 (CI 95%, 0.69-0.87), 0.87 (CI 95%, 0.80-0.95), 0.64 (CI 95%, 0.53-0.75), and 0.92 (CI 95%, 0.86-0.98) for the 4 attendings and a hand fellow, respectively. Fifty-seven percent of angiograms were interpreted as having loss of ulnar artery patency at the wrist (type 2) with 77% having additional loss of superficial palmar arch patency (type 2A).

CONCLUSIONS

This large series of angiograms in patients with systemic sclerosis demonstrates a classification system for conventional angiography that shows high inter-rater and intrarater reliability using type alone. When subtypes were used, the inter-rater and intrarater reliabilities decreased to moderate and moderate-to-high, respectively.

CLINICAL RELEVANCE

This study represents the first step in establishing a classification system that, by grouping patients with similar angiogram findings, may allow for targeted research into risk stratification, monitoring, and treatment in systemic sclerosis.

CT and MR imaging of the upper extremity vasculature: pearls, pitfalls, and challenges

Imaging is needed for diagnosis, treatment planning, and follow-up of patients with pathologies affecting upper extremity vasculature. With growth and evolution of imaging modalities [especially CT angiography (CTA) and MR angiography (MRA)], there is need to recognize the advantages and disadvantages of various modalities and obtain the best possible imaging diagnostic test. Understanding various limitations and pitfalls as well as the best practices to minimize and manage these pitfalls is very important for the diagnosis. This article reviews the upper extremity arterial vascular anatomy, discusses the CTA and MRA imaging, various pitfalls, and challenges and discuss imaging manifestations of upper extremity arterial pathologies.

Anatomical Variation of the Radial Artery Associated With Clinically Significant Ischemia

PURPOSE

The purpose of this retrospective review was to investigate the incidence of radial artery anatomical variations in patients with clinically significant distal upper extremity (UE) ischemia. Available anatomical studies report that high takeoff of the radial artery occurs in up to 15% of the population. We hypothesized that there is a higher incidence of high origin of the radial artery in patients with clinically significant ischemia compared with the reported frequency in the general population.

METHODS

We performed a retrospective review of all patients who underwent UE angiography for clinically significant hand and digital ischemia in our institution from 2012 to 2016. Data collected included patient age, sex, comorbidities, and modality of treatment.

RESULTS

Twenty-six angiograms were performed for UE ischemia meeting inclusion criteria. Eight patients had Raynaud disease or scleroderma. Ten patients (38%) had high radial artery takeoff with radial artery origin proximal to the antecubital fossa. The need for surgical intervention was similar in patients with normal anatomy and those with high takeoff of the radial artery.

CONCLUSIONS

Incidence of high radial artery takeoff was found more frequently in patients with distal UE ischemia requiring angiogram than in reported population data.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic IV.

Deep tissue photoacoustic computed tomography with a fast and compact laser system

Photoacoustic computed tomography (PACT) holds great promise for biomedical imaging, but wide-spread implementation is impeded by the bulkiness of flash-lamp-pumped laser systems, which typically weigh between 50 - 200 kg, require continuous water cooling, and operate at a low repetition rate. Here, we demonstrate that compact lasers based on emerging diode technologies are well-suited for preclinical and clinical PACT. The diode-pumped laser used in this study had a miniature footprint (13 × 14 × 7 cm³), weighed only 1.6 kg, and outputted up to 80 mJ per pulse at 1064 nm. In vitro, the laser system readily provided over 4 cm PACT depth in chicken breast tissue. In vivo, in addition to high resolution, non-invasive brain imaging in living mice, the system can operate at 50 Hz, which enabled high-speed cross-sectional imaging of murine cardiac and respiratory function. The system also provided high quality, high-frame rate, and non-invasive three-dimensional mapping of arm, palm, and breast vasculature at multi centimeter depths in living human subjects, demonstrating the clinical viability of compact lasers for PACT.

Nonoperative Management of Acute Upper Limb Ischemia

BACKGROUND

Acute upper limb ischemia (AULI) is an uncommon emergency warranting immediate evaluation and treatment. The role of nonsurgical therapies including endovascular techniques, thrombolytics, and anticoagulation remains undefined. The authors systematically reviewed the current literature on the nonsurgical treatment of acute ischemia of the upper extremity.

METHODS

A PubMed and Embase search was conducted, and articles were screened using predetermined criteria. Data collected included patient demographics, cause of upper limb ischemia, type of nonsurgical treatment used, treatment outcomes, and complications. Patients were divided into 4 treatment groups: catheter embolectomy, catheter-directed thrombolysis, endovascular stenting, and anticoagulation/medical therapy alone.

RESULTS

Twenty-three retrospective studies met the search criteria. Of 1326 reported occlusions, 92% (1221) were attributed to thromboembolic disease. The second most common cause was iatrogenic (1.5%). Overall limb salvage rates were excellent with catheter embolectomy (862 of 882 cases, 97.7%) and catheter-directed thrombolysis (110 of 114 cases, 96.5%). Limb salvage rates were also high with anticoagulation/medical therapy (158 of 165 cases, 95.8%), but poor functional outcomes were more often reported.

CONCLUSIONS

High-quality evidence to guide the nonsurgical treatment of AULI is lacking. Retrospective studies support the utility of catheter-based embolectomy and thrombolysis for distal ischemia. Whether a surgical or nonsurgical approach is taken, anticoagulation therapy remains a mainstay of both treatment and prevention of AULI. Because AULI patients often have underlying cardiac and/or systemic disease, a multidisciplinary approach is essential to minimize complications and prevent future occurrences.

Upper Extremity Runoff: Pearls and Pitfalls in Computed Tomography Angiography and Magnetic Resonance Angiography

Upper extremity vasculature can be affected by various traumatic and nontraumatic pathologies; however, the evaluation of these arteries can be challenging for the radiologists as well as for the clinicians. After an accurate history and clinical examination, imaging plays a vital role in the diagnosis and treatment planning of these patients. Depending on the urgency and the indication, upper extremity arteries may be evaluated by ultrasonography with color Doppler, computed tomography (CT), magnetic resonance imaging (MRI), or digital subtraction angiography. This review article discusses relevant imaging anatomy of the upper extremity arteries, presents CT and MRI protocols, briefly describes the state-of-the-art CT and MRI of various pathologies affecting the upper extremity arteries, and summarizes the important pearls needed for busy practicing radiologist.