2015 HSC Section 1 Book of Articles

A. Tekes et al. / Clinical Radiology 69 (2014) 443 e 457

and often times seen in the setting of syndromes such as KT. Even in those patients with KT, LM and VM are seen sepa- rately ( Figs 1 and 10 ). Mixed LVMs are generally found as super fi cial lesions in fi ltrating the skin or tongue ( Fig 11 ). Cavernous malformation-arteriovenous malformation CM-AVM is an autosomal dominant condition that con- sists of cutaneous CMs and high- fl ow arteriovascular mal- formations. These lesions are also formed due to a RASA1 mutation. On physical examination, the CMs, previously described as port-wine stain, are fl at reddish lesions. 42 In contrast to typical CMs, those associated with CM-AVM are usually smaller, multiple, and associated with an encircling pale halo. 43 Treatment usually involves embolization of the underlying AVM. VaMs can also be associated with syndromes ( Table 4 ). In contrast to isolated VaM, limb overgrowth is more common in the syndromal VaM. KT, blue rubber bleb nevus syndrome (BRBNS), unilateral limb VM, mucocutaneous VMs, Stur- ge e Weber, Proteus, Congenital Lipomatous Overgrowth, Vascular Malformations, and Epidermal Nevi (CLOVE) syn- drome, Maffucci, and Gorham e Stout syndromes are all associated with low fl ow-VaM. Parkes e Weber, Rendu e Osler e Weber, Cobb and Wyburn e Mason syn- dromes are associated with high- fl ow VaM. PTENmutations in syndromes such as Bannayan e Riley e Ruvalcaba and Cowden syndromes also result in high- fl ow VaM. 44,45 We will discuss some of the more commonly encountered syn- dromes associated with VaM. Klippel – Trenaunay syndrome KT is characterized by hypertrophy of the affected limb with slow- fl ow VaMs, including CMs of the skin with un- derlying extensive VMs and/or LMs ( Figs 1 and 11 ). Dysplastic/anomalous veins or persistent embryonic veins can be observed. The deep venous system may be atretic, hypoplastic, or abnormal in approximately 50% of patients with KT and must be con fi rmed patent prior to ablation of the super fi cial abnormal veins. These patients can vary from a mild form, to a more severe form with extensive involvement of the pelvis and viscera as well as the legs. Some may have more LMs, others may have more VMs, and some may have enlarged ectatic pelvic and leg veins. KT patients may also be at higher risk for pulmonary embolus and need to be evaluated for potential long-term anticoagulation. 46 Blue rubber bleb nevous syndrome BRBNS is characterized by multiple cutaneous VMs as well as internal VMs, typically involving subcutaneous tis- sues and muscles in numerous locations ( Figs 1 and 12 ). Cutaneous lesions are often present shortly after birth and increase in size and number with growth of the child. Physical examination fi ndings demonstrate small, bluish Syndromes associated with vascular malformations Syndromes associated with venous malformations

raised lesions, which can often be painful. These patients must be followed due to multiple small bowel lesions that frequently bleed, presenting in early adulthood as slow, chronic gastrointestinal bleeding and chronic iron- de fi ciency anaemia. 47,48 Unilateral limb venous malformation Some patients with diffuse VMs in an extremity do not have KT (no hypertrophy, no LM, no port-wine stain) and are classi fi ed as having unilateral limb VM 49 ( Figs 1 and 13 ). The skin may appear bluish due to the VM in the subcu- taneous region. They typically have numerous deeper VMs within muscles from the pelvis to the feet. Mucocutaneous venous malformation This is an autosomal dominant inherited VM with mul- tiple bluish spots that are usually small and punctuate and painful to touch, but may be larger in size. 32 Glomuvenous malformation This is also an autosomal dominant inherited VM in which there are multiple small bluish to purple skin le- sions 32 ( Figs 1 and 14 ). Parkes e Weber syndrome Parkes e Weber syndrome (previously called Klip- pel e Trenaunay e Weber syndrome) is not a VM syndrome, but is characterized by hemihypertrophy of usually the lower limb, CM, and diffuse multiple tiny super fi cial arte- riovenous shunts 50 ( Figs 1 and 15 ). Unlike KT, Par- kes e Weber is a fast- fl ow malformation due to the presence of arteriovenous fi stulas. Pathogenesis is due to a RASA1 gene mutation on chromosome 5q13.1. RASA1 gene encodes for p120-RasGAP protein that promotes signalling of several growth factor receptors involved in proliferation, migration, and survival of vascular endothelial cells. On physical ex- amination, the lesion is usually pinkish to red with diffuse areas of involvement. 51 MRI is helpful in classifying the malformation as a fast fl ow arterial or AVM, which helps differentiate from KT. Treatment usually involves multi- staged embolizations to improve high-output cardiac fail- ure and help save the limb. Syndromes associated with arteriovenous malformations ISSVA classi fi cation not only provides accurate diagnosis, but also provides a common language for clinicians involved the care of the vascular anomalies. SEMVAFC in- corporates the ISSVA classi fi cation to provide a clear visual pathway and a practical multidisciplinary approach to ac- curate classi fi cation of highly complex VA. References 1. Hassanein AH, Mulliken JB, Fishman SJ, et al. Evaluation of terminology for vascular anomalies in current literature. Plast Reconstr Surg 2011; 127 :347 e 51 . Conclusion

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