What is Wyburn-Mason Syndrome?
Wyburn-Mason syndrome, also known as racemose angioma, is a birth defect that doesn’t run in families. It is a type of disorder that affects both the nervous system and the skin, causing growths called arteriovenous malformations (AVMs). AVMs are tangled blood vessels that can lead to a variety of health issues. While Wyburn-Mason syndrome can affect different parts of the body, it most commonly affects the face and brain. This syndrome was first identified by three people – Bonnet, Dechaume, and Blanc in 1937, and then described more thoroughly by a person named Wyburn-Mason in 1943. As such, it is sometimes referred to as Bonnet-Dechaume-Blanc syndrome or Wyburn-Mason syndrome.
AVMs can range in size, often growing large, and when they are in the brain, they usually appear in an area called the midbrain. Doctors use neurological imaging techniques to check for potentially threatening or harmful lesions in this area. In the eye, a doctor can see these AVMs as swollen and twisted vessels that start at the optic nerve and extend out into the rest of the retina. The severity of vision problems can vary widely, depending on related eye complications. A person with Wyburn-Mason syndrome might also have abnormal blood vessels in other parts of their body. Aside from instances of tiny facial angioma (a collection of blood vessels that form a benign tumor) on the face, visible skin manifestations of Wyburn-Mason syndrome are rare.
What Causes Wyburn-Mason Syndrome?
Wyburn-Mason syndrome is a condition that someone is born with. It’s not hereditary, meaning it can’t be passed on from parents to children. At the moment, doctors aren’t sure what exactly causes it, but it’s thought to occur because of an abnormality during the development of organs in a baby’s body. This might lead to the spread of vascular lesions, or damages to blood vessels, originating from the head and spreading along the path before the cells from the blood vessels actually reach their final destination.
This condition is part of a system known as cerebrofacial arteriovenous metameric syndrome (CAMS), a system that describes different variations of AVM, or abnormal connections between arteries and veins, in the brain, eyes, and face region. CAMS consists of three types:
– CAMS1 involves the corpus callosum (a band of nerve fibers in the brain), hypothalamus (a small region of the brain that controls many bodily functions), olfactory tract (involved in the sense of smell), forehead, and nose.
– CAMS2 includes parts of the cortex (an outer layer of the brain), diencephalon (an area at the base of the brain), optic chiasma (where optic nerves cross), optic nerve, retina (the light-sensitive layer of tissue at the back of the eye), sphenoid (a bone at the base of the skull), maxilla (upper jaw bone), and cheek. Wyburn-Mason syndrome falls into this category.
– CAMS3 involves the cerebellum (a part of the brain that controls movement), temporal bone (one of the bones that make up the side of the skull), and mandible (lower jaw bone).
Risk Factors and Frequency for Wyburn-Mason Syndrome
Wyburn-Mason is a very rare condition, with less than 100 cases recorded globally. This condition doesn’t affect any particular gender or race more than others. Research suggests that around 30% of patients who show symptoms in their eyes (retinal findings) also have signs in their brain. Meanwhile, about 8% of patients with brain symptoms show signs in their eyes as well.
- Large arteriovenous malformations (issues in the blood vessels) in the retina often lead to vision or nervous system problems and are usually diagnosed early in life.
- Smaller arteriovenous malformations might not cause symptoms, or they might only be discovered later in life.
Signs and Symptoms of Wyburn-Mason Syndrome
Wyburn-Mason syndrome is characterized by a variety of neurological symptoms, which usually depend on where the arteriovenous malformations (abnormal connections between arteries and veins) are located and their size. Common symptoms can include seizures, headaches, partial paralysis, visual problems, cranial nerve disorders, and hydrocephalus (a condition where there is an accumulation of cerebrospinal fluid in the brain).
Arteriovenous malformations located outside the brain can lead to blood in urine, coughing up blood, nosebleeds, or severe bleeding. The syndrome usually affects one eye, but in rare cases, it could involve both eyes. Tiny arteriovenous malformations within the eye may not cause any visual symptoms, while larger ones can lead to serious loss of vision.
- Seizures
- Headaches
- Partial paralysis
- Visual problems
- Cranial nerve disorders
- Hydrocephalus
- Blood in urine
- Coughing up blood
- Nosebleeds
Eye-related from this syndrome can include droopy eyelid, bulging of the eye, irregular eye movement, bleeding in the retina or vitreous humor (the clear gel filling the inside of the eye), retinal detachment, blockage of the veins in the retina, swelling of the optic disc, and wasting away of the optic nerve. Abnormal blood vessels in the eye socket can also cause pulsating bulging of the eye along with unusual sounds, known as bruits.
Most individuals show signs related to the eye at a young age and can have serious visual impairment. Early diagnosis of arteriovenous malformations can indicate a high risk for the involvement of the entire body.
Testing for Wyburn-Mason Syndrome
Wyburn-Mason syndrome is a condition that gets diagnosed through a clinical exam. One notable feature of this syndrome is that the blood vessels in the retina (the layer at the back of the eye that senses light) are abnormally connected, which is referred to as retinal arteriovenous malformations. These malformations typically get identified using a procedure called ophthalmoscopy, which involves examining the inside of the eye. A test called fluorescein angiography might be necessary for spotting smaller malformations. This test uses a special dye to highlight the blood vessels in the retina. It’s essential to note that most of these malformed blood vessels do not “leak” when viewed during the test.
Other tools like ultrasound and a method called optical coherence tomography (OCT) can also be used to confirm the presence of Wyburn-Mason syndrome, and to track changes in the nerve fiber layer, the macula (the small area in the retina that provides our sharpest vision), and the rest of the retina over time. OCT can be particularly handy for diagnosing other related conditions like swelling in the macula (macular edema) and fluid buildup under the retina (serous retinal detachment).
If the condition causes the eyes to bulge, which is called proptosis, a tool called an exophthalmometer can be used to measure the severity of the bulging.
Wyburn-Mason syndrome can also feature malformed blood vessels in the brain, or intracranial arteriovenous malformations. These can be identified using imaging techniques like computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance angiography (MRA), or cerebral arteriography. A procedure called catheter angiography, which uses a dye and special x-rays to see inside the blood vessels, is considered the best way to understand the precise structure of the abnormal blood vessels. This method can provide details about the size, location, and features of these vessels.
Though rare, this syndrome can sometimes include lesions on the skin. Typically, malformations in the brain’s blood vessels are found on the same side as the eye that’s affected. Most often, these malformations are found in the midbrain, which is the part of the brain responsible for motor control, vision, hearing, and temperature regulation.
Treatment Options for Wyburn-Mason Syndrome
If you are diagnosed with Wyburn-Mason syndrome, the treatment that you receive depends on the exact location of the arteriovenous malformations in your body and the symptoms you’re experiencing. Arteriovenous malformations are abnormal connections between arteries and veins. If these malformations have not ruptured and you’re not having symptoms, your doctor might choose to just monitor your condition.
There are different treatment options to consider. These include radiation therapy, which uses high-energy waves to destroy the abnormal vessels; embolization, where a substance is injected to block the blood vessels; or surgical resection, which means surgically removing the malformations. In some cases, a combination of these approaches is used.
Intracranial arteriovenous malformations are located in your brain. These are usually watched carefully because there is a 2.2% risk per year that they could rupture. However, brain surgeries carry higher risk of complications, so if you only have mild symptoms like mild bulging of the eye or mild drooping of eyelid, doctors usually recommend observation and managing symptoms.
Retinal arteriovenous malformations are in your eyes and most do not bleed externally. However, they can cause small internal bleeds which affect your vision. Doctors who specialize in eye health, called ophthalmologists, will diagnose the condition, get brain imaging done, organize referrals to other specialists, and perform regular eye checks. But if complications occur, treatment is required.
For example, if you develop neovascular glaucoma, a type of eye condition that affects pressure and circulation in the eye, you may need treatments, such as:
– Retinal photocoagulation: This uses a special kind of laser to help with retinal ischemia (damage caused by lack of blood flow).
– Pars plana vitrectomy: This is a surgery to remove and replace the fluid inside the eye to treat bleeding.
– Cyclodestructive procedures: These are treatments that reduce the pressure in the eyes and may be used if you have painful blind eyes due to neovascular glaucoma.
Additionally, if you have macular edema, which is swelling in the central area of your retina, it can be managed through injections of anti-VEGF agents. These are medications that help to reduce fluid accumulation and improve vision.
What else can Wyburn-Mason Syndrome be?
When doctors are trying to diagnose Wyburn-Mason Syndrome (WMS), they consider several other related conditions that might cause similar symptoms. Some of these conditions include:
- Von Hippel Lindau syndrome: This condition is linked with symptoms like retinal capillary hemangioma (an orange-red retinal lesion), cerebral aneurysm, kidney cancer, and pheochromocytoma (a rare type of tumor). Unlike WMS, this syndrome is inherited. Physicians generally recommend abdominal imaging tests to check the kidneys.
- Vasoproliferative tumors (VPT): These are retinal nodules made up of glial cells and blood vessels. VPT can be a primary condition or it can occur due to other retinal diseases like retinitis pigmentosa or coat’s disease. In case of VPT, cryotherapy is often used for treating retinal detachment.
- Sturge Weber syndrome: This can be suspected in cases where there are facial angiomas (port-wine stains) or glaucoma. Sturge-Weber syndrome is also associated with hemangiomas of the meninges (membranes that cover the brain).
- Retinal cavernous hemangioma: This appears as a dark grape-like cluster of venous intraretinal aneurysms. The characteristic finding is hypofluorescence until the late phase with a slow non-leaking filling of the aneurysms.
It’s crucial for physicians to take these possibilities into account and perform relevant tests for an accurate diagnosis.
What to expect with Wyburn-Mason Syndrome
The course and treatment of Wyburn-Mason syndrome (WMS) are not definitively known, which makes it difficult to predict the future health outcomes for people with this condition. Some people with WMS may never develop any symptoms at all, while others may experience more severe symptoms.
If the disease causes visual symptoms, the range and severity of these symptoms largely determine the person’s health outcomes. For example, if fluid builds up in the back of the eye (called macular edema), injections into the eye might be necessary to help manage this. If the eye fills with blood that does not clear on its own (nonclearing vitreous hemorrhage or VH), a surgical procedure might be performed to remove the blood.
An eye condition called neovascular glaucoma, which is typically characterized by high eye pressure and abnormal blood vessel growth in the eye, can be treated with laser therapy to control the abnormal blood vessels and therapies to lower the pressure in the eye.
However, regardless of the specific treatments undertaken, the overall health prognosis for people with visually symptomatic WMS remains uncertain.
One unique aspect of WMS to be aware of is the potential for heavy bleeding during dental procedures, stemming from involvement of the blood vessels in the face and jaw. Because of this, dental professionals need to be aware of this possible complication when treating these patients.
The appropriateness of using surgery to treat brain arteriovenous malformations (abnormal tangle of blood vessels in the brain, referred to as “intracranial AVMs”) in people with WMS is a topic of ongoing debate. Some reports suggest that people who’ve had bleeding in the brain from an AVM could potentially have good outcomes following surgery. However, surgical removal of AVMs in certain locations in the brain could potentially risk harming vision and the visual field (the total area one can see).
Given these potential risks, many surgeons prefer to manage these brain AVMs in a more conservative, non-invasive manner.
Possible Complications When Diagnosed with Wyburn-Mason Syndrome
Complications tied to AVM, or abnormal connections between arteries and veins, can include bleeding in the brain or damage because of mechanical pressure. Possible eye complications include fluid leakage from the AVM causing swelling in the macula (the part of the eye responsible for sharp, central vision), insufficient blood supply to the retina, clotting of the veins in the retina, a type of glaucoma caused by new blood vessels growing on the eye’s iris, and bleeding in the vitreous, the jelly-like substance that fills the back of the eye.
Complications could also arise from brain surgery, including loss of vision or a decrease in the area a person can see.
In addition, dental or upper jaw surgeries could cause excessive bleeding due to the presence of these AVMs.
Common Complications:
- Bleeding in the brain
- Damage due to mechanical pressure
- Fluid leakage causing swelling in the macula (eye)
- Insufficient blood supply to the retina (eye)
- Clotting of the veins in the retina
- Type of glaucoma caused by new blood vessels on the iris
- Bleeding in the vitreous (eye)
- Loss of vision or decrease in vision field from brain surgery
- Excessive bleeding caused by surgery of the teeth or upper jaw due to AVM presence
Preventing Wyburn-Mason Syndrome
Patients with WMS (Williams Syndrome) should be informed that they will need regular check-ups to identify any complications from their Arteriovenous Malformation (AVM) early on. AVM refers to an abnormal connection between arteries and veins, which can lead to serious issues if not managed appropriately.
Brain surgeries should only be considered for a select group of patients. For example, those experiencing serious bleeding as a result of their AVM or suffering from severe vision loss in one eye might need this form of treatment.
Generally, it’s better to avoid brain surgeries in patients who show no symptoms or only mild symptoms. These surgeries are major procedures and come with their own risks, so they’re usually reserved for more severe cases.
