CONGENITAL ANOMALIES AND VASCULAR BIRTHMARKS OF THE LOWER EXTREMITIES

Soft Tissue Vascular Anomalies of the Extremities: A Proposed Diagnostic Approach

This narrative review aims to summarise the classification of vascular anomalies, their clinical presentation, and their radiological features to propose a diagnostic algorithm to approach patients with suspected soft tissue vascular anomalies of the extremities. The management of vascular anomalies necessitates a multidisciplinary approach. Clinical presentation and physical examination are sufficient in most cases to achieve a correct diagnosis. This is especially true for small congenital lesions of the skin and subcutaneous tissue. Imaging is used for accurate characterization of these lesions, especially in cases of atypical or vague clinical presentation, and to assess extension in cases of lesions that are larger and localized in deeper tissues.

Bleomycin for Head and Neck Venolymphatic Malformations: A Systematic Review

BACKGROUND

Venolymphatic malformations are rare benign vascular lesions of the head and neck. Sclerotherapy has become the first-line therapy of these lesions with bleomycin being a sclerosing agent commonly used.

PURPOSE

To perform a systematic review of the published literature to synthesize evidence on the safety and efficacy of bleomycin for the treatment of head and neck venolymphatic malformations.

DATA SOURCES

A systematic review of the literature (January 1995-May 2019) was performed in PubMed, Embase, and Cochrane Library databases to identify studies on sclerotherapy of venolymphatic malformations of the head and neck.

STUDY SELECTION

A total of 32 studies with participants met the inclusion criteria among which 1121 patients were included in the systematic review.

DATA ANALYSIS

Two reviewers independently screened and extracted data and assessed the risk of bias. The primary outcome was the subjective or objective reduction of lesion size as well as minor and major complications.

DATA SYNTHESIS

The bleomycin/pingyangmycin sclerotherapy achieved subjective or objective lesion size reduction in 96.3% (95% CI 94.1%-98.5%) of patients. Minor complications were observed in 16.2% and major complications in 1.1%.

CONCLUSION

Bleomycin is a highly effective treatment of venolymphatic malformations of the head and neck with a low rate of major adverse events. This study represents an update on the "available" evidence, but only low-to-moderate quality studies were available.

LIMITATIONS

This study reviewed 32 studies performed in different parts of the world, but there was heterogeneity of the study designs and interventions.

Percutaneous treatment of orofacial vascular malformations

The aim of this study was to evaluate the efficacy of fluoroscopy-guided percutaneous injection of bleomycin as the primary treatment for low-flow vascular malformations. A total of 34 patients (mean (range) age 24 (8-51) years) with orofacial vascular lesions were treated in the Department of Interventional Radiology and Maxillofacial Surgery. There were 20 low-flow venous malformations, 11 lymphatic malformations, and three of mixed type. All patients were treated by fluoroscopy-guided percutaneous injection of a mixture of bleomycin (mean (range) 15 (5-15)mg) and a radio-opaque agent (Ultravist^® (iopromide), Bayer)/session. The number of sessions ranged from one to six. The clinical response was complete in 21 patients, obvious in nine, and of clinical benefit in four. Patients were reviewed within the first week, third week, and at three-month periods until 24 months. There were no serious complications such as pulmonary fibrosis. Fluoroscopy-guided intralesional injection of bleomycin should be considered as the first-line treatment for lymphatic malformations because it is effective and reliable with few complications.

Soft-tissue vascular malformations and tumors. Part 2: low-flow lesions

Vascular malformations and tumors, also known as "vascular anomalies", comprise an extensive variety of lesions involving all parts of the body. Due to a lack of a complete understanding of the origin and histopathology of such lesions, this field has been traditionally obscured by the use of an unclear nomenclature. Knowledge of the classification and clinical and imaging characteristics of this group of lesions is paramount when managing these patients. The objective of this series of two articles is to review the current classification of vascular anomalies, to describe the role of imaging in their diagnosis, to summarize their distinctive histopathologic, clinical and imaging features, and to discuss the treatment options. High-flow lesions were discussed in the first article of this series. In this second article, we will focus on low-flow lesions, including complex syndromes with associated low-flow malformations.

Klippel-trénaunay syndrome with intracranial arteriovenous malformation: a rare presentation

Klippel-Trénaunay syndrome (KTS) is a rare vascular congenital anomaly affecting less than 200,000 people in the United States. Vascular malformations associated with KTS tend to affect slow flow systems: venous, capillary, and lymphatic systems. The nature of the syndrome leads to a higher risk for the development of arteriovenous malformations. Our case presentation describes a patient with KTS and an associated rare presentation of intraventricular arteriovenous malformation (AVM).

Ten frequently asked questions about MRI evaluation of soft-tissue vascular anomalies

OBJECTIVE

The objective of this article was to address 10 frequently asked questions that radiologists face when planning, performing, and interpreting an MRI study in a patient with a soft-tissue vascular anomaly.

CONCLUSION

MRI permits a comprehensive assessment of vascular anomalies. It is important for radiologists to be familiar with the classification and correct nomenclature of vascular anomalies as well as the MRI protocol and distinct imaging findings of the different vascular malformations and tumors.

Klippel-Trenaunay Syndrome Causing Life-Threatening GI Bleeding: A Case Report and Review of the Literature

Klippel-Trenaunay syndrome (KTS) is a rare congenital syndrome of vascular malformations and soft tissue and bone hypertrophy. Vascular malformations can affect multiple organ systems. Involvement of the gastrointestinal (GI) tract is uncommon in KTS, but it can be a source of life-threatening bleeding. We report a case of a 32-year-old male with a known diagnosis of KTS who presented with a life-threatening rectal bleeding and was treated with proctosigmoidectomy and massive blood products transfusion. He expired after a long hospitalization. We then review the literature on KTS and management of some of its complications.

MR imaging of soft-tissue vascular malformations: diagnosis, classification, and therapy follow-up

Vascular malformations and tumors comprise a wide, heterogeneous spectrum of lesions that often represent a diagnostic and therapeutic challenge. Frequent use of an inaccurate nomenclature has led to considerable confusion. Since the treatment strategy depends on the type of vascular anomaly, correct diagnosis and classification are crucial. Magnetic resonance (MR) imaging is the most valuable modality for classification of vascular anomalies because it accurately demonstrates their extension and their anatomic relationship to adjacent structures. A comprehensive assessment of vascular anomalies requires functional analysis of the involved vessels. Dynamic time-resolved contrast material-enhanced MR angiography provides information about the hemodynamics of vascular anomalies and allows differentiation of high-flow and low-flow vascular malformations. Furthermore, MR imaging is useful in assessment of treatment success and establishment of a long-term management strategy. Radiologists should be familiar with the clinical and MR imaging features that aid in diagnosis of vascular anomalies and their proper classification. Furthermore, they should be familiar with MR imaging protocols optimized for evaluation of vascular anomalies and with their posttreatment appearances. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.315105213/-/DC1.

Pediatric soft-tissue tumors and pseudo-tumors: MR imaging features with pathologic correlation: part 1. Imaging approach, pseudotumors, vascular lesions, and adipocytic tumors

A wide spectrum of entities may give rise to soft-tissue masses in children, including benign and malignant tumors, pseudotumors, and both neoplastic and nonneoplastic vascular lesions. Because of its excellent tissue contrast, multiplanar capability, and lack of ionizing radiation, magnetic resonance (MR) imaging has become the modality of choice in the evaluation of deep and large soft-tissue masses in children. In the vast majority of cases, however, accurate interpretation of the MR imaging findings requires correlation with the clinical findings. For example, in most posttraumatic and inflammatory pseudotumors, the clinical history is fundamental to establishing the diagnosis. In the evaluation of periarticular cysts, the location of the mass and its relationship to a joint are crucial for diagnosis, whereas in the evaluation of vascular lesions, including hemangiomas and vascular malformations, clinical findings combined with MR imaging findings are needed for accurate diagnosis in most cases. The identification of fat within adipocytic tumors is useful, but tissue biopsy may be required for final diagnosis. Nevertheless, MR imaging is useful in determining the origin and character of pediatric soft-tissue masses, defining their extent and their relationship to adjacent structures, and performing posttherapy follow-up.

MRI characteristics and classification of peripheral vascular malformations and tumors

Vascular malformations and tumors comprise a broad spectrum of lesions that can cause significant morbidity and even mortality in children and adults. Classification of vascular malformations into high flow and low flow has significant impact on management since the main treatment of the former is transarterial embolization and the later percutaneous sclerotherapy. Magnetic resonance imaging (MRI) is a noninvasive effective tool for imaging and classification of vascular malformations based on the presence of lobulated masses, signal voids, and hemodynamic flow characteristics. MRI also provides details about anatomic extent of the lesion, proximity to vital structures, and involvement of multiple tissue planes. The prototype of vascular tumors is infantile hemangioma with its typical involution after a proliferative phase during infancy. Hemangioma appears as a distinct intensely enhancing soft tissue mass with enlarged feeding arteries and draining veins. Less common vascular tumors include congenital hemangioma, kaposiform hemangioendothilioma, angiolipoma, angiosarcoma, and hemangiopericytoma.

Venous malformations: MR imaging features that predict skin burns after percutaneous alcohol embolization procedures

OBJECTIVE

To examine the value of magnetic resonance (MR) imaging for predicting the occurrence of skin burns in patients with venous malformations who undergo percutaneous alcohol embolization was the objective of the study.

MATERIALS AND METHODS

Pre-procedural MR imaging at 1.5 T from 40 patients with venous malformations who had undergone percutaneous alcohol embolization was retrospectively reviewed by two observers for these features: anatomic location, definition (well-defined or ill-defined), and the presence of skin, subcutaneous tissue, muscle, tendon, bone, joint, and deep venous system involvement. One observer recorded the length of skin involvement and volume of the malformation. Univariate and multivariate analysis tests were used to determine whether an association between the occurrence of skin burns and MR imaging features existed.

RESULTS

The anatomic locations of the venous malformations were the lower extremity (20 out of 40), upper extremity (11 out of 40), trunk (four out of 40), head/neck (three out of 40) and pelvis (two out of 40). Of the 40 subjects, 15% (six out of 40) experienced skin burns. There was a significant association between the absence of muscle involvement (p = 0.0198) as well as the length of skin involvement (p = 0.027), with the occurrence of skin burns. Malformation size and all other features were not significantly associated with skin burns.

CONCLUSION

Skin burns in patients with venous malformations treated with alcohol embolization are associated with the length of skin involvement and with the absence of deeper tissue involvement, as depicted on MR imaging.

Role of MRI in paediatric musculoskeletal conditions

The aim of this review is to discuss the indications and use of MR imaging (MRI) in the paediatric musculoskeletal system. After briefly reviewing basic technical considerations the MRI appearance of the most relevant congenital, inflammatory, infectious, ischemic, and posttraumatic skeletal conditions, as well as benign and malignant bone and soft tissue tumours that are typical for the paediatric age group will be presented.

Klippel-Trenaunay syndrome: a multisystem disorder possibly resulting from a pathogenic gene for vascular and tissue overgrowth

Klippel-Trenaunay syndrome is characterized by a triad of varicose veins, cutaneous capillary malformation, and hypertrophy of bone and soft tissue. Appropriate evaluation and treatment of children displaying features of the disease may minimize morbidity. The clinical appearance, etiology, genetics, diagnostics, and treatment of Klippel-Trenaunay syndrome are herein explored.

Vascular malformations in the extremities: emphasis on MR imaging features that guide treatment options

Vascular malformations can be classified into high-flow arteriovenous malformations (AVM) and low-flow venous or lymphatic malformations (VM/LM). VMs and LMs have the ability to cross multiple tissue boundaries. Not only is subcutaneous tissue often involved, but multiple muscle groups, tendons, bone cortex and bone marrow are also not uncommonly violated. Magnetic resonance imaging (MRI) provides valuable information for the assessment and treatment of malformations. Firstly, MRI can characterize the flow pattern of these malformations to guide treatment towards trans-arterial embolization for AVMs and percutaneous embolization for low flow malformations. MRI is essential to define the anatomic extent and involvement of various tissue layers (a distinct advantage over ultrasound), and to correlate treatable components of the malformation with patient symptoms. Treatment is decided by the need to alleviate clinical symptoms, and is dependent on the extent of the malformation as defined by MRI. We present MRI features of vascular malformations to demonstrate the potential spectrum of involvement of these lesions, illustrating the value of MRI in treatment planning.

Magnetic resonance imaging findings of vascular malformations of the lower extremity

Vascular malformations are congenital lesions resulting from a defect during embryogenesis. Magnetic resonance imaging (MRI) is a very effective method for demonstrating detailed information regarding involved structures, extent, and flow characteristics of vascular malformations. In previous MRI studies, most of the emphasis is laid on the difference between high- and low-flow lesions, whereas little detailed information is available about the extent of local tissue involvement. These additional characteristics may influence the approach in treating these malformations and improve understanding of the pathogenesis. We retrospectively reviewed MRI scans of 40 patients with vascular malformations of the lower extremity. Thirty-four patients had low-flow lesions, and six had high-flow lesions. Of the low-flow lesions, 23 patients (67.6 percent) had muscle infiltration, with four of the six high-flow lesions having muscle infiltration. Nine of the 11 male patients (81.8 percent) with low-flow lesions had associated muscle infiltration, in comparison with 14 of the 23 female patients (60.9 percent) with low-flow lesions (p = 0.206). Eighty percent of the vascular malformations located on the thigh with muscle involvement had involvement of the anterior muscle group, whereas 86.6 percent of the patients with a vascular malformation located on the leg and with associated muscle involvement had at least the posterior muscle group involved (p = 0.0049). Ten patients (25 percent) of the whole group had bone infiltration. Low-flow lesions often had multifocal lesions (20.6 percent), whereas associated muscle atrophy was visible in 10 low-flow lesions and in two high-flow lesions. In low-flow lesions with muscle infiltration (n = 23), 43 percent (n = 10) had associated surrounding muscle atrophy (p = 0.009). Hypertrophy of the subcutaneous tissue was visible in 11 low-flow patients (32.4 percent). The high amount of muscle and bone involvement in vascular malformations of the lower extremity is emphasized with this study. Of particular interest was the difference in affected muscle groups. The angiosome concept is used to explain this preponderance, and we feel the angiosome concept could also be used when assessing possible intervention. The surrounding muscle atrophy and multifocal nature of these anomalies are further important considerations when assessing the possibility of intervention.

Use of magnetic resonance imaging for the evaluation of vascular malformations of the lower extremity

Vascular malformations are anatomically subdivided according to the predominant channel anomaly into either capillary, arterial, venous, lymphatic, or combinations. They can be further subdivided into high- or low-flow malformations. Any lesion that has an arterial component is considered a high-flow malformation. Once the diagnosis of a vascular malformation is made, it is of paramount importance to define not only the flow characteristics but also the full range of extension, because the prognosis and appropriate treatment vary substantially for each type of anomaly. The two most useful noninvasive imaging techniques for assessing vascular malformations are magnetic resonance imaging (MRI) and ultrasonography. The aim of this review is to give surgeons involved in treating patients with vascular malformations an opportunity to gain some background on MRI scans when assessing vascular malformations. Although MRI is a powerful modality for assessing vascular malformations, we will also discuss some of the limitations of MRI. We further suggest a diagnostic flow chart developed on the basis of MRI features designed to help determine the composition of a vascular birthmark when intervention is anticipated.