الفهرس 
Pathology, Pathogenesis & Clinical PictureOnly 14 pages are availabe for public view
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Abstract
The treatment of vascular anomalies is a relatively new and rapidly developing discipline
that requires a broad interface between several surgical and medical specialities. (Kubiena H et
al., 2007)
In 1982, Glowacki and Mulliken proposed a “biological” classification of vascular anomalies
based on clinical behavior, histology, and histochemistry. Following this classification, which
has been accepted by the International Society for the Study of Vascular Anomalies (ISSVA) in
1996, vascular anomalies are divided into vascular tumors (e.g., hemangiomas), in which the
etiology is one of endothelial cell proliferation, and vascular malformations, in which a
developmental error has caused abnormally formed vascular channels. Vascular malformations
are subdivided based on the channel type and on flow characteristics. This classification has
helped resolve the confusion regarding terminology in the field of vascular anomalies. (Kubiena
H et al., 2007)
Congenital vascular malformations (CVMs), including arteriovenous malformations
(AVMs), remain an enigma despite efforts during the last century to improve their care. They
have a wide range of clinical presentation and an unpredictable course. Complicated
anatomical, pathological, physiological, embryonic and hemodynamic characteristics must be
evaluated. High morbidity has been related to both surgical and nonsurgical treatments. There
has been an associated high recurrence rate. (Lee BB et al., 2004)
Among CVMs, AVMs have been particularly confusing because of their unpredictable
nature. AVMs behave aggressively as a primitive type of CVM because the majority belong to
the extratruncular form as the residual remnants of a developmental arrest in the early stage of
embryonic life. They have a tendency to progress with a more destructive potency. (Lee BB et
al., 2004)
Introduction & Aim of the Work 2
The primary effect of an AVM on the surrounding tissues is by the lesion itself, with
compression and erosion. Secondary hemodynamic effects include a potential arterial steal
phenomenon. The heart can be affected by high-output cardiac failure. Peripheral tissues can be
affected in a wide range of changes from distal ischemia to gangrene, venous stasis dermatitis,
and ulcer or gangrene caused by venous hypertension. (Lee BB et al., 2004)
AVM, especially its infiltrating extratruncular form, has a high recurrence rate because of
its origin from the mesenchymal cells at an early stage of embryogenesis. It retains the
evolutional potential to grow, which is often represented clinically as a recurrence. Its behavior,
therefore, is totally unpredictable, often responding to various stimulations such as injury or
surgical intervention, as well as a systemic hormone effect. The result can be explosive growth.
Improper treatment often stimulates dormant AVM to grow rapidly, making the condition
worse. This recurrence and unbridled growth are the trademarks of AVM. (Lee BB et al., 2004)
As no single specialist has sufficient knowledge to diagnose and treat vascular
malformations in all organ systems, interdisciplinary teams have formed to exchange their
knowledge and to elaborate specific evaluation standards. This is fundamental for proper
diagnosis, prognosis, and treatment.(Kubiena H et al., 2007)
Vascular malformations are best managed by a vascular anomalies team in a facility
equipped and experienced in the management of vascular anomalies. Such a vascular
anomalies team might include a vascular interventionalist, dermatologist, plastic surgeon,
orthopedic surgeon and/or neurosurgeon, pediatrician, and physiotherapist.(Marshalleck F and
Johnson MS, 2006)
Complete eradication of the nidus of an AVM is the only potential “cure.” But this, however,
is often difficult if not impossible. Radical resection to remove the lesion completely has been
described as “demolishing surgery.” It is often accompanied by excessive blood loss in addition
to serious complications. Thus, incomplete removal of the AVM is a frequent result of attempts
to avoid the high morbidity associated with total excision. (Lee BB et al., 2004)
Chapter 1 3
New diagnostic technology, including less invasive imaging, has aided the differential
diagnosis of CVM to provide a more precise diagnosis of AVM developed in different stages of
embryogenesis. Contemporary diagnosis, based on the Hamburg classification, provides an
opportunity for implementation of the new concept of a multidisciplinary team approach for
managing AVM. This approach is based on a new classification scheme and diagnostic
technology.(Lee BB et al., 2004)
Embolo/sclerotherapy is a new therapeutic modality that is accepted as independent
therapy, especially for surgically inaccessible lesions. It has also been implemented as
preoperative or postoperative adjunct therapy. It has helped improve surgical results and to
expand the role of surgical therapy. (Lee BB et al