Angiomas and vascular malformations are tumors or developmental malformations originating from the vascular system, collectively known as vascular anomalies, and about 60% of them occur in the head and neck. (A) Classification and naming In the past, the classification and naming of hemangioma and vascular malformation were relatively confusing, mostly called hemangioma or lymphoma, and named mainly according to the morphology of the lesion. For example, capillary hemangioma, cavernous hemangioma and vascular hemangioma are included in hemangioma, and capillary, cavernous and cystic types are included in lymphadengioma. In 1982, Mulliken and Glowacki proposed a new classification in terms of cell biology and pathology to clearly distinguish between tumors and malformations. These two types of lesions. Since then, Jackson et al. (1993), the International Society for the Study of Vascular Anomalies (ISSVA, 1998), Waner and Suen (1999) have added to and improved on Mulliken et al. In 2002, at the National Symposium on Treatment and Research of Oral and Maxillofacial Hemangiomas held by the Specialized Committee of Oral and Maxillofacial Surgery of the Chinese Society of Oral Medicine, the participants agreed that the concept, classification and nomenclature of hemangiomas and vascular malformations should be redefined, and unanimously recommended the application of Waner and Suen’s classification and nomenclature: 1. hemangioma). 2.Vascular malformation (vascular malformation). (1) Microvenous malformation (venular malformation): including two types of midline microvenous malformation and microvenous malformation. (2) Venous malformation (venous malformation). (3) Arteriovenous malformation (arteriovenous malformation). (4) lymphatic malformation: it is divided into two categories: microcystic and macrocystic. (5) Mixed malformation: including venous-lymphatic malformation and venous-venular malformation. If the above classification is compared with the traditional classification, the following characteristics are roughly shown: 1. Strawberry-like hemangioma in the traditional classification is a true tumor, i.e. hemangioma, while all others are vascular malformations. 2.Microvenous malformations are added from histopathological point of view. Microvenous is finer than capillary vein (50-200μm), the wine-colored spots in the traditional classification belong to microvenous malformations, and the cavernous hemangioma in the traditional classification should be venous malformations. 3.Microcystic type of lymphatic duct malformation includes capillary type and cavernous type of lymphatic duct tumor in traditional classification, while macrocystic type is equivalent to cystic type or cystic hydatid tumor in traditional classification. 4. The veno-lymphatic malformation in the mixed type is the spongy type lymphangioangioma in the traditional classification and common in clinical practice, while the microcystic type refers to the capillary type lymphangioangioma or lymphangioangioma in the traditional classification. (B) Hemangioma Hemangioma, also known as infantile hemangioma (IH), is the most common benign tumor of vascular origin in infants and children, most often seen at birth (about 1/3) or within 1 month after birth. Its origin and pathogenesis are unknown. It is more common in females (male to female ratio of 1:3-5) and is associated with factors such as prematurity, low birth weight, progesterone use during pregnancy, and chorionic villus puncture examination during pregnancy. The histopathological features of hemangiomas are tumors rich in proliferating active vascular endothelial cells, with angiogenesis and mast cell aggregation. Hemangiomas occurring in the oral and maxillofacial region account for approximately 60% of all hemangiomas in the body, most of which occur in the skin and subcutaneous tissues of the face and neck, and a few are found in the oral mucosa. Deep and intra-mandibular hemangiomas are currently considered to be vascular malformations. The biological behavior of hemangiomas is characterized by spontaneous regression. The course of the disease can be divided into three phases: the proliferative phase, the regressive phase and the complete regressive phase. According to the depth of tumor invasion, it can be divided into superficial, deep and compound types. The proliferative stage is initially characterized by capillary dilatation surrounded by a halo-like white area; it quickly turns into erythema and rises above the skin, resembling a prune with uneven height. With the first growth period of infants, it grows rapidly after about 4 weeks, and this is often the most urgent period for parents to seek treatment. If it grows on the head and neck, it may not only cause deformity, but also affect the function, such as sucking, breathing, vision, etc.; some cases may also be complicated by infection, ulceration, bleeding, etc. Rapid proliferation is also seen during the second growth spurt of infants, i.e., at 4 to 5 months of age. It usually enters the regressive phase after 1 year. The process of regression is slow, and the lesions change from bright red to dark purple and brown, and the skin can be florid. According to statistics, the fading rate is about 50% to 60% at the age of 5, 75% at the age of 7, and 90% at the age of 9. However, there is no method to determine whether and to what extent hemangioma can be receded. The complete receding rate is only 40%, and most of them are incomplete. (C) Vascular malformation 1.Venous malformation. Traditionally classified as cavernous hemangioma, it is composed of numerous blood sinuses lined with endothelial cells. The blood sinuses vary in size and shape, like sponge structures. The blood in the sinus cavity coagulates into a thrombus and can calcify into a vein stone. Venous malformations are found in the cheek, neck, eyelid, lip, tongue, or floor of the mouth. The location varies in depth, with normal skin or mucosal color if the location is deep; superficial lesions appear blue or purple. The borders are indistinct, soft to palpate, compressible, and sometimes venous stones can be palpated. When the head is below the level of the heart, the area of the lesion is engorged and enlarged; when the normal position is restored, the swelling then shrinks and returns to its original state, which is called a positive postural shift test. Venous malformations are often undetected at birth, and some are brought to the patient’s attention in early childhood or even in adulthood when symptoms appear. When the venous malformation is small in size, there are usually no conscious symptoms. If the blood sinuses continue to dilate, the lesions may develop and become larger, causing deformities and dysfunction of the face, lips, and tongue. If infection occurs, it can cause pain, swelling, surface skin or mucous membrane ulcers and risk of bleeding. 2.Microvenous malformation. It is commonly known as wine stain. It is mostly found on the skin of face and face, often distributed along the distribution area of trigeminal nerve, and rare in oral mucosa. It is bright red or purplish red, flat with skin surface and clear boundary. Its shape is irregular and its size varies, from small spots to several centimeters, and large ones can extend to one side of the face or cross the midline to the opposite side. When the lesion is compressed with fingers, the surface color recedes; when the pressure is released, blood immediately fills the lesion area and restores the original size and color. According to the size of microvein diameter, microvein malformation is divided into 4 grades, and most of the lesions show a gradual development trend from grade I to grade IV, and the clinical symptoms become more and more severe, from simple skin erythema to cobblestone-like nodules. Microvenous malformation is often a manifestation of certain syndromes, with Sturge-Weber syndrome being the most common. In addition to facial microvenous malformations, patients may have glaucoma and cerebrovascular malformations. Midline microvenous malformations are mainly lesions located in the midline, most commonly in the collar, followed by interfrontal, interbrow, and upper lip areas. Unlike wine stains, 60% of the lesions can fade on their own. 3. Arteriovenous malformation. This is the traditional classification of trabecular hemangioma. It is a curved, irregular and pulsating vascular malformation. It is mainly formed by the direct anastomosis of arteries and veins with significantly dilated vessel walls, during which there is a lack of capillaries, so it is actually a capillary malformation. Arteriovenous malformations are more common in adults and less common in young children. It often occurs in the temporal or subscalp tissues where the superficial temporal arteries are located. The lesions are elevated and rosaceous, with a higher surface temperature than normal skin. Patients may feel the pulsation themselves; there is a tremor on palpation and a blowing murmur on auscultation. The pulsation and murmur in the lesion disappears if all of the blood supplying arteries are pressed shut. The lesion may erode the bone at the base or may protrude into the skin, causing thinning and even necrosis and bleeding. Jugular vein anger is common in the neck. 4.Lymphatic duct malformation. It is formed by the abnormal development of lymphatic vessels. It is common in children and adolescents. It is commonly found in the tongue, lips, cheeks and neck. According to its clinical characteristics and tissue structure, it can be divided into two types: microcystic type and macrocystic type. (1) Microcystic type: It includes capillary type and spongy type lymphangiectasia. It is formed by the expansion of lymphatic vessels lined with endothelial cells. The lymphatic vessels are extremely dilated and curved, forming a multi-housed cystic cavity, which resembles a sponge. The lymphatic vessels are filled with lymphatic fluid. They present as isolated or multiple scattered small round cystic nodular or punctate lesions on the skin or mucosa, which are colorless, soft, generally non-compressible, and have indistinct lesion borders. Lymphadenopathy of the oral mucosa sometimes coexists with microvenous malformations and presents with small yellow or red blister-like protrusions called lymphadenopathy-microvenous malformations. Deep microvenous malformations occurring in the face, lips, and submandibular region often result in significant hypertrophy and deformity of the affected area. If it occurs in the tongue, it often appears as megalingualism, causing jaw deformity, open zaozi001, reverse zaozi001, tooth displacement, and occlusal disorder. The surface of the tongue mucosa is rough, nodular or vein-like, with small yellow blisters protruding. On the basis of long-term chronic inflammation, the tongue body can become hard. (2) Large cystic type: the cystic type or cystic hydatidiform tumor (hydroma) in the traditional classification. It occurs mainly in the neck and supraclavicular region, but also in the submandibular region and the upper neck. The lesions are usually multi-compartmental cystic cavities, spaced apart from each other and containing clear, yellowish, watery fluid. The lesions vary in size, have normal skin color, are filled, and are soft and volatile on palpation. Unlike deep hemangioma, the body movement test is negative, but the transillumination test is positive. 5.Mixed type of vascular malformation. When there is more than one type of vascular malformation, it can be called mixed type of vascular malformation. Such as the aforementioned microvenous malformation and microcystic lymphatic malformation coexist, angioma and vascular malformation, microvenous malformation and venous malformation coexist, etc. (iv) Diagnosis The diagnosis of superficial hemangioma or vascular malformation is not difficult. Deeper angiomas or vascular malformations should be determined by postural mobility testing and puncture examination. For arteriovenous malformations as well as venous malformations in deep tissues and large cystic lymphatic malformations, ultrasound, arteriography, lesion lumpectomy, CT angiography (CTA), magnetic resonance angiography (MRI or MRA) can be used to assist in the diagnosis in order to determine their location, size, extent and their anastomotic branches (for details of the methods, see Diagnostic Oral and Maxillofacial X-Ray and related reference books) and to provide a provide a basis for treatment and efficacy evaluation. From the point of view of cell biology classification, vascular lesions in adults are basically vascular malformations. Immunohistochemical studies have confirmed that glucose transporter protein 1 (Glut-1) is positively expressed in infantile hemangioma tissues, while vascular malformations are negatively expressed, which is the most significant difference between hemangiomas and vascular malformations. In addition, the levels of vascular endothelial growth factor (VEGF) and estradiol in serum and basic fibroblast growth factor (bFGF) in urine were significantly elevated in patients with proliferative hemangioma; and the apoptotic gene bcl-2 was highly expressed in vascular malformations, which can be used as a reference in the diagnosis. Arteriovenous malformations are somewhat different from aneurysms (aneurysm) or acquired arteriovenous fistula. An aneurysm is an aneurysmal dilatation of the arterial wall caused by a lesion of the middle elastic fibers; an acquired arteriovenous fistula is a localized dilatation of the artery after injury, or even rupture into the accompanying vein, usually located deeper and more limited. False aneurysm can also occur after trauma to the maxillofacial neck, mostly in the parotid area or upper neck, and is a pulsatile lesion formed by a ruptured artery with blood stored in the soft tissue; pathological examination reveals fibrous walls and blood clots. The diagnosis can be confirmed by arteriogram. (E) Treatment The treatment of hemangioma and vascular malformation should be decided according to the type of lesion, location and age of the patient. Commonly used treatment methods include drug therapy, laser therapy, surgical excision, and for complex cases, comprehensive treatment is advocated. Except for small and medium-sized lesions that grow in non-aesthetic areas, are stable and do not affect aesthetics and function, which can be treated with a “wait and see” strategy, infants and children should be treated actively to control the growth of hemangioma, accelerate its regression and minimize complications. The use of freezing, radionuclides, and superficial x-rays to treat hemangiomas in the past has been abandoned because of their inaccurate efficacy and complications. Endothelial cells of hemangioma are in embryonic state and are more sensitive to hormone treatment. For proliferative hemangioma, oral high-dose prednisone was preferred for treatment in the past and certain effect was achieved, but the adverse effect of hormone treatment is obvious. Since the good effect of propranolol (Takayasu) on hemangioma was discovered by chance in 2008, oral propranolol has become the first-line drug for the treatment of proliferative hemangioma, with more and more applications and reports. Its advantages are that it has few and mild adverse effects and is also useful in the treatment of receding hemangiomas. A small number of large hemangiomas that involve important areas (e.g., nose, eyelids) or affect function (e.g., breathing, vision) can also be treated surgically at an early stage. The goal of surgical treatment is to improve aesthetics and function, and the pursuit of surgical completeness is not advocated. For hemangiomas that can only be partially removed surgically, other treatments, such as medication and laser treatment, can be used after surgery. Atrophic scars left after hemangioma fading or treatment can be treated with CO2 fractional laser. For capillary dilatation that remains after regression or treatment, 0.25% polyglaucine or 0.2% sodium tetradecyl sulfate injection can be injected locally, and diode laser treatment can also be used. Residual lesions or skin erythema after treatment can be treated with pulsed dye laser. The laser treatment is repeated for 4 to 6 weeks. Venous malformations do not fade on their own and require a clear diagnosis and classification and timely treatment accordingly. Microvenous malformations are mainly treated with the pulsed dye laser, while photodynamic treatment with copper vapor or krypton laser is used in China. Radionuclides, X-rays, and freezing were used in the past to treat microvenous malformations, but they are no longer used because of poor efficacy and complications. Venous malformations can be treated by laser therapy, sclerotherapy and surgery, with sclerotherapy as the main treatment, and commonly used sclerosing agents are 5% sodium cod liver oil acid, pinyamycin and anhydrous ethanol. After the injection within the lesion, the vascular endothelial cells are destroyed, and the lesion tissue is gradually fibrotic and occluded, and eventually shrinks or disappears. When injected, the surrounding tissues can be temporarily compressed to block the blood return flow; the injection is given once in 3-4 weeks, and the dosage depends on the size of the lesion and the speed of venous return flow. Arteriovenous malformations used to be treated mainly by surgery, but the recurrence rate after treatment is high and the damage to the shape and function is great. With the development of interventional radiology, transcatheter arterial embolization (TAE, TCAE) has been successfully used to treat arteriovenous malformations and has become the mainstay of treatment. Diffuse arteriovenous malformations of soft tissue are usually treated with anhydrous ethanol embolization followed by surgical excision of the lesion and revision of the shape. The aim of embolization therapy is to reduce intraoperative bleeding, and the commonly used effective and safe embolization material is anhydrous ethanol. It should be noted that attempts have been made to treat arteriovenous malformations with external carotid ligation alone, but empirical and experimental studies have shown that it is not only ineffective, but also promotes the formation of unopened collateral circulation, making later treatment difficult. The application of external carotid artery ligation for arteriovenous malformations is not only practically ineffective, but also theoretically wrong. In the past, most of the arteriovenous malformations of jaws were treated by jaw resection, but nowadays, we tend to use interventional treatment as much as possible, i.e. “double interventional” treatment combining anhydrous ethanol and metal ring, which can not only cure the lesion, but also preserve the continuity and function of jaws, and should be the first choice of treatment. The treatment of lymphatic duct deformity is based on sclerotherapy injection, which can be combined with surgical treatment, lesion reduction, jaw deformity correction, etc., in order to improve the aesthetics and function, and improve the quality of survival of patients. In recent years, there are more and more clinical reports of using Pingyangmycin to treat hemangioma and vascular malformation, and its main indications are venous malformation and lymphatic vascular malformation, and its efficacy has been confirmed. Since Pingyangmycin is an anticancer drug, its long-term adverse effects remain to be observed. [MS1] Although there are more methods for the treatment of hemangioma and vascular malformation, the problem of treatment for large hemangioma and vascular malformation has not been completely solved and needs to be explored in depth. Multidisciplinary collaboration and the combined application of multiple tools are proven methods for the management of complex cases.