be seen. The diagnosis of hemangioma can best be confirmed by MRI with gadolinium contrast and Doppler ultrasound. But, in rare instances, when the diagnosis of a malignancy cannot be ruled out by imaging or when clinical evolution is atypical, a biopsy becomes mandatory [9].

Summary for the Clinician

■Knowing the three phases of the natural history of IH will help in the diagnosis and management.

■Large segmental IHs may point toward the diagnosis of PHACE(S) syndrome.

■In deep lesions, diagnosis must be confirmed either by imaging or more rarely by biopsy to rule out other potentially lethal lesions.

11.2Ocular Complications

The most frequent ocular complications associated with IHs are related to amblyopia. Amblyopia is most often secondary to astigmatism but can also be due to strabismus or occlusion of the pupil. Risk factors for development of amblyopia are dependent on size and location. In a study of 129 patients by Schwartz et al., lesions measuring less than 1 cm in its greatest diameter were not associated with amblyopia, while lesions of more than 1 cm induced amblyopia in 40 of 75 patients (53%). Fourteen of 18 patients (78%) with large di use lesions had amblyopia [12, 35].

Location of the lesion also plays a significant role. In a study looking at the location of IHs, palpebral lesions induced amblyopia or astigmatism in 13 of 32 patients (40%). When the lesion was orbital with or without intraconal involvement, these findings were present in 27 of 31 patients (87%) [12]. The depth of the lesion also appears to be related to the length of the growth phase, with deeper lesion having a more prolonged period of growth. Lesions involving the lid, nasal location, involvement of the lid margin, or presence of a ptosis appear to have a higher incidence of amblyopia [40].

Hemangiomas can also cause strabismus either by a mass e ect causing misalignment of the eye or by direct involvement of the extraocular muscles causing anomalies in the movement of the involved eye. In a series of 51 cases of hemangiomas of the eyelids, the most common complications were amblyopia (43%) and strabismus (33%). It was felt that milder forms of amblyopia in the

11.3Investigation 163

range of 6/12 to 6/30 were caused by anisometropia or strabismus [42]. In another study, strabismus was present in 15% of cases with eyelid or orbital lesions, but when large lesions part of PHACES syndrome were present, the strabismus incidence was much higher (71%). Visual loss can also be secondary to optic nerve involvement either by direct compression or by ischemic changes due to compression of the optic nerve supply. In rare cases, exposure and scarring of the corneal surface can also cause visual impairment and contribute to refractory amblyopia. Ulcerations are rare in the periocular areas; they typically occur in the proliferative phase and are more common in areas of mechanical trauma. They can be painful and may become infected. Some degree of scarring occurs when they heal [8].

Summary for the Clinician

■Amblyopia is the most important risk for the patient with IH.

11.3Investigation

When a periocular lesion is present and a threat for interference with visual development is suspected, periodic ocular examinations are performed. Measures include visual acuity assessment, evaluation of lid fissures and movement, ocular alignment, and eye movements. Refraction with cycloplegia is performed. The lesion is measured, and photographs are taken for future comparison. Initially, the ophthalmologic evaluation is repeated every 3–6 weeks.

Imaging is needed in cases of deep hemangiomas with normal overlying skin, cases of clinically atypical soft tissue masses, when the evaluation of extension of obvious hemangiomas is necessary, in cases of alarming hemangiomas, and for guiding therapy. Doppler ultrasonography is often the first modality used to delineate and characterize vascular lesions. Its main advantages are its flexibility, availability, cost, and ability to be repeated frequently over time [11]. Dubois and Garel defined the Doppler characteristics of hemangiomas as showing a variable echogenicity mass with increased color flow (Fig. 11.1).

The lesion displays high vessel density (>5 vessels/ cm2) with a high Doppler shift (>2 kHz) and low resistance. Typically, there is little or no evidence of arteriovenous shunting (i.e., most veins within the lesion remain monophasic) [11]. From a previous study, they showed,

11

Fig. 11.1 Doppler ultrasound showing high vessel density and high peak arterial Doppler shift characteristic of infantile hemangioma

Fig. 11.2 Child with nasal infantile hemangioma and moderate astigmatism

by using the two criteria of high vessel density and high peak arterial Doppler shift for the diagnosis of hemangioma, a sensitivity of 84%, specificity of 98%, and positive predictive value of 97% and negative predictive value of 82% of the Doppler examination [13]. During the involution phase, the lesion will show regression in size and number of vessels, although the remaining vessels will show a persistence of the high systolic flow.

On computed tomographic (CT) scan, proliferative hemangiomas present a lobular pattern of homogeneous masses. They show intense and persistent enhancement with infusion. When undergoing involution, they lose this intense staining and appear as heterogeneous masses with fibrofatty changes. CT scan is a modality of imaging that is used sparingly in infants to limit unnecessary exposure to radiation.

On MRI, hemangiomas are typically of intermediate signal intensity on T1-weighted sequences and increased signal intensity on T2-weighted sequences. The presence of

Fig. 11.3 After gadolinium injection on T1, the lesion is enhanced and shows intraorbital involvement nasally

flow voids within and around the soft tissue mass is an important feature on MRI.Increased signal intensity on both T1and T2-weighted sequences correlates with hemorrhage or fatty deposition histologically [3, 11] (Fig. 11.1–11.3).

11.3.1 Angiography

Angiography is indicated in cases of heart failure resistant to medical treatment (e.g., secondary to hepatic involvement) and in cases of the Kasabach–Merritt syndrome for endovascular treatment. It is almost never used in periocular hemangioma of infancy except in rare instances where a vascular malformation is suspected [12].

Summary for the Clinician

■Doppler ultrasound is the first imaging modality for IH.

■MRI is used for larger or deeper lesions.