Lymphangioma

Lymphangioma

Lymphangioma is rare, and constitutes less than 7% of childhood orbital tumours. They are benign hamartomatous tumours. Although they are benign in nature, representing 1-3% of all orbital masses, they can sometimes be aggressive in nature. They intertwine with surrounding tissues and increase in size with infections. It usually grows at a slow pace and has a progressive proptosis that is mild initially. The tumour is thought to be congenital, slow growing, and it does not become apparent for months or even years. It occurs in children and teenagers, but most often in the first decade of life.

Symptoms of orbital lymphangioma

Most orbital lymphangiomas are initially asymptomatic. But as they progress gradually, they manifest as proptosis, eye pain and disturbed vision.

Other symptoms include

• Blurry vision
• Double vision
• Red eye
• Bulging eye
• Droopy eyelid
• Glaucoma
• Vision loss

More than 50% of lymphangiomas affect anterior structures like conjunctiva and adnexa. At times lymphangiomas can be mistaken for cavernous hemangiomas. The diagnosis can be clarified by the absence of smooth muscle cells within the wall of the vessels, and the presence of lymph. Orbital lymphangiomas are different from hemangiomas. Orbital lymphangiomas never relapse, while hemangiomas do.

In 55% of cases, spontaneous bleeding occurs within the tumour causing cysts of blood called Chocolate Cysts. The bleeding occurs despite the absence of a blood supply.

If the cyst develops behind the eye ball it pushes the eye forward, forms compressive optic neuropathy and may cause loss of vision. If the tumour forms behind the eyelid or around adnexa, it can manifest into blood filled lymphatic channels called lymphangiectasias that are formed beneath the conjunctiva.

The orbital cyst can enlarge rapidly over few hours or within a day or two, presenting with a sudden onset of eyelid swelling or proptosis. The increase in volume can cause pressure and pain, and it can be risky for the patient’s eye. Multiple acute episodes of cyst enlargement are the major feature of this tumour.

How is orbital lymphangioma diagnosed?

Lymphangioma usually presents as a sudden painful bulging of the affected eye. This tumour may or may not have a history of facial trauma or that the tumour or proptosis may start right after an upper respiratory tract infection.

Physical examination of anterior segment of the eye reveals bluish discoloration of blood vessels within the skin of the eyelid. The blood vessels can often extend underneath the conjunctiva, called lymphangiectasias. Severe cases might be linked with corneal exposure, ulceration and optic nerve damage.

For a patient with a typical history of pain with proptosis, ultrasound is the first line of investigation. To establish the diagnosis of lymphangioma, computed tomography (CT) or Magnetic Resonance Imaging (MRI) can be done, which can also demonstrate extra-orbital extensions.

What is the treatment for orbital lymphangioma?

Orbital lymphangioma is an unusually slow growing tumour and therefore is monitored by observation for growth both clinically and radiographically before considering any definitive intervention. If the lymphatic proliferation is not extreme and the bulk of the lesion and the cysts are not threatening vision, immediate treatment may not be needed.

Some lymphangiomas never require treatment. But if there is bleeding or lymphatic proliferation that causes cyst expansion and compromises the optic nerve or causes severe proptosis, then usually intervention is the need of the hour. Acute headache, ocular pain and ocular neuropathy are the result of hemorrhage.

Surgical intervention is required only if there is symptomatic presentation. Surgery is done to remove the cystic component, debulk the lesion and decompress the orbit. In children, vision cannot be compromised.

The following signs are an indication of a severe form of orbital lymphangioma. Hence, an active intervention might be needed.

• Sudden spurt in tumour growth
• Optic nerve compression
• Corneal exposure problems like keratitis sicca
• Glaucoma
• Vision loss

Most of the orbital lymphangiomas are poorly defined in their extensions or edges. So, a complete removal may not be considered. In most of the cases, the patients are treated with several debulking surgeries to relieve acute optic nerve compression or corneal exposure. In rare cases, these patients might possibly require exenterating the orbit, or radiation therapy for pain relief. Treatment options have often included conservative management, systemic steroids, partial surgical resection and radiology procedures.

Whereas the treatment is concerned, orbital lymphangioma is a challenging disease and is often difficult to treat with good visual outcome. Usually this tumour is known for witnessing cosmetic complications and the possibility of frequent recurrences. Orbital lymphagiomas has a high recurrence rate.  Recently experts have come across new approaches that might be helpful in some cases. One of the alternatives to surgical resection is the intralesional injection of a sclerosing agent. Radiation therapy has not been proven to be effective for orbital lymphangiomas.

Dr. Debraj Shome is a highly experienced oculoplastic surgeon based in India.