The Baseline Workup and Diagnosis

When a doctor suspects PHACE syndrome, they move quickly to look beneath the surface of the skin. Because the hemangioma is just one part of the condition, a thorough baseline workup—a set of initial tests—is necessary to understand how the brain, heart, and eyes have developed ^[1][2].

The 2016 Consensus Criteria

In 2016, experts established a standardized way to diagnose PHACE syndrome. Medical specialists apply these criteria using a combination of the physical exam and imaging results. It is divided into two categories based on what the tests show:

• Definite PHACE: This diagnosis is made when a child has a large characteristic facial hemangioma (larger than 5 cm) plus one “major” internal finding (such as a specific brain or heart abnormality) or two “minor” findings ^[2][3].
• Possible PHACE: This diagnosis applies when a child has the characteristic hemangioma (> 5 cm) plus one “minor” internal finding; OR when a smaller hemangioma or nonfacial segmental lesion is present alongside one “major” criterion; OR when two major criteria are present without a hemangioma ^[2][4].

It is important to remember that these criteria (major and minor) are defined technical categories used by specialists to help doctors organize care; they do not predict exactly how severe the syndrome will affect your child’s daily life.

Why Small or “Deep” Marks Matter

A common misconception is that only very large, bright red hemangiomas are “risky.” However, research shows that even small or deep (subtle, bluish, or under-the-skin) hemangiomas can be associated with PHACE syndrome ^[5][6].

This is especially true for periorbital hemangiomas (those around the eye) ^[7]. In one specific study cohort, nearly 18% of children with these types of marks—including those smaller than 5 cm—were found to have internal findings related to PHACE, though this estimate may not apply to all periorbital hemangiomas ^[5]. If a mark is in a segmental pattern (covering a specific “territory” of the face), it may warrant a full evaluation, but the extent of testing should be individualized according to the location, associated findings, and specialist assessment ^[6][5].

The Essential Baseline Tests

To confirm a diagnosis and check for potential complications, doctors typically order the following “typical baseline evaluations” tests:

1. MRI and MRA of the Brain and Neck: An MRI (Magnetic Resonance Imaging) takes detailed pictures of the brain structure, specifically looking at the posterior fossa (the back of the brain) ^[1]. An MRA (Magnetic Resonance Angiogram) is a specialized scan that focuses specifically on the blood vessels (arteries) to see if they are narrow, twisted, or missing ^[2][8]. Note: MRI in infants often requires sedation and sometimes contrast dye, which carry their own considerations.
2. Echocardiogram: This is an ultrasound of the heart. Doctors use it to look at the aortic arch, the main pipe that carries blood from the heart to the rest of the body, to check for any narrowing or unusual shapes (coarctation) ^[2][9]. Additional cardiac imaging may be needed when the arch cannot be adequately visualized.
3. Targeted Eye Exam: A pediatric ophthalmologist will perform a complete exam to look for structural differences in the eye or the optic nerve ^[10]. They also check for functional issues like ptosis (a drooping eyelid) or strabismus (misaligned eyes), which can affect how a child’s vision develops ^[11][12].

Why Early Diagnosis Is Critical

The goal of these tests is to identify any internal differences before they cause symptoms. For example, knowing about a narrowed heart artery or an unusual brain vessel allows doctors to monitor your child more closely and intervene early if needed ^[2][8]. Early diagnosis also helps the medical team decide if certain common treatments for hemangiomas, such as beta-blockers, are safe for your specific child ^[1].

By completing this workup, you and your medical team move from “watching and waiting” to a proactive plan tailored to your child’s unique anatomy.