Vascular Anomalies Flashcards
(23 cards)
What are vascular anomalies?
Congenital anomalies caused by abnormal growth of blood vessels, forming masses of variable shapes filled with blood.
Where do vascular anomalies commonly occur?
Head and neck region
What complications can vascular anomalies cause?
1) Cosmetic issues
2) Hemorrhage
+ Other serious complications
How do vascular anomalies differ in appearance from congenital nevi?
Vascular anomalies appear in blood-colored shades, while nevi appear in melanin-colored shades.
What is the key clinical importance of distinguishing vascular anomalies from congenital nevi?
Congenital nevi are premalignant, whereas vascular anomalies are not premalignant
What are the two main groups of vascular anomalies in Mulliken and Glowacki’s classification?
1) Hemangiomas
2) Vascular malformations
Why is Mulliken and Glowacki’s biological classification preferred today?
1) It is based on clinical behavior and endothelial cell characteristics
2) The two subtypes differ in prognosis, outcome, and management!!
Why does the term “hemangioma” include the suffix “-oma”?
Because hemangiomas behave like tumors, though they are not true neoplasms and are not premalignant.
What is the most common tumor of the head and neck in infancy and childhood?
Hemangiomas
Hemangiomas are vascular anomalies caused by:
Endothelial cell proliferation
What are the characteristics of endothelial cells in hemangiomas?
1) Plump
2) Active
3) High mitotic activity
4) Many mitotic figures = indicates rapid division
Endothelial cells have receptors to mediate ___ cellular proliferation.
Cellular proliferation
In between the endothelial cells there are ___.
Mast cells
Endothelial cells in hemangiomas are considered as:
Embryonic cells with short doubling time
When do hemangiomas typically first appear?
Around 3–4 weeks of age
How do hemangiomas appear at first?
Starting de novo or as tiny lesions
When do vascular malformations typically first appear?
At birth
What are the 2 phases of hemangiomas?
1) Proliferative phase
2) Involution or regression phase
The proliferative phase of hemangiomas is characterized by:
Relatively rapid early growth until 6 to 12 months of age.
The proliferative phase of hemangiomas is characterized by:
How long does the Involution or regression phase last?
Until 5 to 9 years of age
Why does the hemangioma expand and grow rapidly in the proliferative phase?
Mast cells increase in number = playing a role in neoangiogenesis
