Plastic Surgery for Capillary Malformations 

Updated: Oct 21, 2020
Author: Rohit Seth, MD, PhD, MRCS(Edin); Chief Editor: Gregory Gary Caputy, MD, PhD, FICS 

Overview

Practice Essentials

Capillary malformations are a form of vascular anomaly that present in patients at birth. Vascular anomalies make up a spectrum of disorders involving the endothelium and can be classified broadly into vascular tumors and vascular malformations. As elucidated by Mulliken and Glowacki, these categories, representing the only two major types of vascular birthmarks, reflect differences in clinical, histologic, hematologic, and radiologic/skeletal features. Their analysis of 49 specimens highlighted a number of key differentiating factors, with the histologic features considered to be the most important. Indeed, plump endothelia, increased mast cells, and multilaminated basement membranes characterize hemangiomas, while flat endothelia, normal mast cell numbers, and a thin basement membrane distinguish vascular malformations.[1]  It is imperative to understand the key differences between these malformations in order to determine the most appropriate management.[1]

A 12-year-old boy presenting with bluish discolora A 12-year-old boy presenting with bluish discoloration of the right thenar eminence and index finger. The lesion has been present since birth and changes in size when he raises his arms or exercises strenuously. Upon physical examination, the mass is soft and rubbery. No palpable thrill or audible bruit is present.
An image from an MRI study of the right hand of th An image from an MRI study of the right hand of the patient in the image above, detailing the vascularity of the lesion.
Intraoperative view of the lesion in the first and Intraoperative view of the lesion in the first and second images shown above. Note the irregular mass of vessels that are adherent to the digital neurovascular bundles, tendons, and lumbrical muscle belly.
The excised specimen from the patient in the previ The excised specimen from the patient in the previous images.

Hemangiomas

Subsequent to Mulliken and Glowacki's report, Enjolas and Mulliken described congenital hemangiomas as separate from infantile hemangiomas, being present at birth (as opposed to infantile hemangiomas, which most commonly appear within the first month of life). They described two varieties: rapidly involuting congenital hemangiomas (RICH) and noninvoluting congenital hemangiomas (NICH).[2]

North et al highlighted the presence of human glucose transporter 1 (GLUT-1) isoform as a useful differentiating factor between infantile hemangiomas and other vascular anomalies. GLUT-1 is uniquely expressed on the endothelial cells of hemangiomas and is not seen in congenital hemangiomas (RICH, NICH), vascular malformations, pyogenic granulomas, or granulation tissue.[3]  Leon-Villapalos et al confirmed these findings in a cohort of patients with vascular anomalies over a 7-year period and found 19 cases of juvenile/infantile hemangiomas, all but one positive for GLUT-1 expression; two cases of NICH that were negative for GLUT-1 expression; 29 cases of vascular malformations (8 capillary, 11 lymphatic, 7 venous, 3 arteriovenous), all negative for GLUT-1; and eight negative controls (4 pyogenic granulomas and 4 granulation tissue samples), all negative for GLUT-1.[4]

Vascular malformations

Vascular malformations result from faulty embryogenesis, resulting in structural and morphologic anomalies. Their appearance can fluctuate in response to changes in blood pressure gradients and flow, collateral formation development, shunting, and changes in hormonal status.[5] Most lesions are mixed, and the predominant vessel is used to describe the lesion. They are not considered neoplastic lesions and are commonly associated with skeletal deformities and hypertrophy. These lesions are commonly present at birth and grow proportionally as the child grows. They also grow with puberty, infection, or trauma and do not involute or regress. They tend to be difficult to remove, as the edges are diffuse and may infiltrate important nerves and vessels.

The natural history of the lesion is dictated by its hemodynamic and lymphodynamic characteristics, ie, whether the lesions are high (fast) flow or low (slow) flow. The low-flow group is composed of capillary malformations, venous malformations, and lymphatic malformations or a combination of these. High-flow lesions include arterial malformations and arteriovenous malformations and are typically associated with bruits, thrills, pulsations, and increased temperature. They expand with increased blood pressure/increased flow and secondary to trauma/surgery by collateral blood vessel formation.[1]

Epidemiology

Frequency

The prevalence at birth of capillary malformations is reported at 0.3% without predisposition to either sex.

Etiology

Genetic studies have mapped capillary malformations to chromosome 5q14-21, showing a defect in the RASA1 gene. The RASA1 gene encodes p120 Ras GTPase-activating protein. When mutated, p120 Ras GTPase-activating protein binds to Krev-1/rap1a, an integrin β1–mediated cell adhesion and angiogenesis protein. The pathogenesis of capillary malformations is not understood.[6]

Pathophysiology

Capillary malformations

Unlike a hemangioma, which is a vascular neoplasm, a port wine stain (which is technically an outdated term) is a capillary malformation with progressive dilation of superficial dermal vessels. It is almost always present at birth and appears equally among males and females.

Port wine stains appear mainly on the face and upper trunk but can also develop on the extremities. While 45% of facial port wine stains are contained in one dermatome, 55% cross over.[7] Lesions can vary in shade, depending on the underlying vessels (see the classification below), and grow in proportion to the growth of the child. Over time, if not treated, the lesions may become nodular, taking on a "cobblestone" appearance, and can also undergo hypertrophy, as can the surrounding soft tissue.[8] This may affect psychological well-being and personal development.[9]

Most port wine stains are clinically harmless but may be associated with Sturge-Weber, Klippel-Trenaunay, or Parkes-Weber syndrome. Periocular involvement can result in glaucoma, necessitating the need for treatment, and midline cephalic or spinal capillary malformations could indicate possible encephalocele or spinal dysraphism.[10, 11]

Wagner Classification [12] (Open Table in a new window)

Grade 1

 

Sparse, pale, nonconfluent discoloration

Grade 2

Denser pink, nonconfluent discoloration

Grade 3

 

Red, discrete, ectatic vessels

Grade 4

 

Confluent patch

Grade 5

 

Nodular lesion

Prognosis

A literature review by van Raath et al looking at an approximately three-decade–long period starting in 1986 reported that treatment outcomes for port wine stains did not improve over these 30 years. The investigators found that 75-100% clearance was obtained in 21% of patients but that mean clearance did not demonstrate an upward trend over time.[13]

 

Workup

Approach Considerations

Cases should be discussed in a formal multidisciplinary meeting involving plastic surgery, pediatrics, dermatology, interventional radiology, hematology, physiotherapy, and histopathology.

Imaging Studies

Most lesions do not require investigation; for concerning lesions, however, appropriate imaging studies include ultrasonography (US), computed tomography (CT) scanning, magnetic resonance imaging (MRI), and spinal radiography.[14]

Magnetic resonance angiography can be used to help document the presence or absence of enlarged vessels in vascular anomalies.

Doppler studies can be used to evaluate the flow pattern of the lesion. Arterial malformations demonstrate high flow; this is a noninvasive method of differentiating them from capillary malformations

Histologic Findings

Ultrastructural characteristics and endothelial mitotic activity are normal in capillary malformations. Typical Weibel-Palade bodies, smooth endoplastic reticulum, and fenestrated postcapillary venules may be observed using electron microscopy. Capillary malformations do not stain for GLUT-1, a marker for infantile hemangiomas, so this test can be used to distinguish between the two lesions.[3, 4]

Other Tests

Ophthalmologic examination should be performed if there is periocular involvement, being carried out every 6 months for the first 3 years and then annually.[11]

 

Treatment

Medical Therapy

Medical therapy includes monitoring the lesion with appropriate imaging if an associated syndrome is suspected. Regular ophthalmologic review is also necessary when there is periocular involvement.[11]

Uncommonly, capillary malformations bleed after minor trauma, and the bleeding can be difficult to stop. Compression of the area and immediate medical assistance may be necessary. Topical timolol can be used to help stop bleeding.

Attempts can be made to conceal the lesion using specially designed water-resistant makeup. The use of superficial tattooing has also been described.

Compression garments and physiotherapy may be required for patients with associated limb edema.

Surgical Therapy

Laser therapy

The current treatment of choice for capillary vascular malformations is the flashlamp-pumped pulsed-dye laser, although only 15-20% of lesions clear completely.[15, 16]  The 585 nm wavelength is most commonly used for a duration of 450 μsec, which is long enough to heat the vessels but not the surrounding tissue.[17] The anatomy of the malformation, however, ultimately guides the physician's choice of laser parameters.

Photothermolysis, using ultrashort pulses of yellow light, targets superficial vessels, improving the appearance of the lesion by lightening the color. Immediately following therapy, skin can develop edema and purpura. The safety of pulsed-dye laser therapy can be enhanced by cooling the skin during treatment. Skin cooling also allows the use of higher wavelengths and fluences. Cooling strategies include the use of convective air cooling, ice cubes, cold gels, cryogen spray cooling, and aluminum rollers.[18, 19, 20, 21, 22, 23]

The therapeutic response is better in the head and neck region compared with the extremities, with superior outcomes seen for lesions in the periorbital region, neck, and temple. Small and/or lighter lesions and patients with skin types I-III also respond better.[10]

The outcome for treatment with pulsed-dye laser is better when administered at a younger age, as response is improved and fewer treatments are thus required.[10]  This therapy is not as effective in patients with skin types IV and V and is associated with more complications such as hypertrophic scarring. Skin lesions can recur, but not to the extent seen prior to the initiation of treatment. Recurrence rates are reported to be 11-50%.

Topical imiquimod has reportedly been used following laser therapy to aid involution of the lesion.[24]  However, this is not yet considered an accepted treatment, although there is ongoing research into this and the use of angiogenesis inhibitors.

Other, less commonly used lasers are KTP (potassium-titanyl-phosphate), Nd:YAG (neodymium-doped yttrium aluminium garnet), and IPL (intense pulsed light), but these are associated with greater side effects.[25]

Surgical treatment

Patients with extensive port wine stains who have not responded adequately to laser therapy or who have been left with hypertrophic lesions, scarring, or hyperpigmentation may require surgical excision and reconstruction with the most appropriate technique. Soft tissue hypertrophy occurs most commonly in the upper lip, and bone hypertrophy occurs most often in the maxillary bone (and can also be treated with surgery). [8]

Cerrati et al described a systematic approach to the surgical treatment of head and neck port wine stains. The main aim of excision is to restore facial symmetry and contour. The authors described techniques of primary resection performed in staged procedures, advising that the bulk of the lesion be resected in the first procedure, while the second procedure be focused more on accurate aesthetic analysis.[7]

Preoperative and postoperative laser therapy can be used to minimize the amount of tissue that needs to be removed. Soft tissue hypertrophy of underlying tissue can cause difficulty in predicting how the overlying skin flap will heal, as it will not be of the same uniformity and depth throughout the lesion; this is another reason that a staged approach is preferred.[7]

Flaps

If the deficit after resection is going to be too large to close primarily using the skin flap, then local flaps, rotational flaps, free flaps, or full-thickness skin grafts may be used. However these are often more noticeable than local skin faded with laser, and with time, skin grafts can also become infiltrated by the port wine stain.

Local flaps may be used with or without tissue expansion. Expansion flaps can be induced to cover the skin deficit left by excision, while causing minimal donor site morbidity and providing a better match for texture and color than full-thickness skin grafts.[26] Tissue expanders are placed in the skin adjacent to the lesion, with the base of the expander being as close as possible to the size of defect. The expanders are then filled every 2-3 weeks, with this being continued until an area of tissue twice the size of the defect has been produced.

Use of free flaps in successful deficit reconstruction has been described. In a series of five patients, thoracodorsal artery perforator free flaps were used for reconstruction, with all flaps surviving without the recurrence of the port wine stain within them.[27]  This option may be used for patients when local flaps are not appropriate.

Orthognathic procedures

When mandibular prognathism or occlusal canting from hemimaxillary vertical overgrowth occurs, orthognathic procedures are indicated. Maxillary overgrowth can be surgically reduced by contouring.

Follow-up

Provide monthly follow-up care to neonates with birthmarks. Hemangiomas begin proliferating within the first month, while capillary malformations enlarge commensurately with the child’s growth. Invasion of important anatomic structures, cosmetic deformity, pain, and swelling may prompt surgical treatment. Monitor patients for recurrence after lesions are resected.

Future and Controversies

Classification of vascular malformations remains controversial. Findings by Breugem et al suggest that the pathologic abnormalities of capillary malformations appear to be located in postcapillary venules rather than in the capillaries themselves.[28] Thus, port wine stains may need to be redefined from their original classification under capillary malformations.

Future advancements in the treatment of capillary malformations include improved selective laser ablation and gene therapy. However, gene therapy remains experimental, with target cells still being evaluated. The use of angiogenesis inhibition is also being researched.