Vitreous humor is a translucent, gel-like substance that fills the middle of the eye including the space between the lens and the retina. In a young and healthy eye, the vitreous humor is sealed to the retina and the macula by a network of microscopic fibers.
With age or due to an eye disease, the vitreous cortex, the shell that houses the vitreous humor, shrinks and detaches from the retina. This condition is referred to as posterior vitreous detachment (PVD). It is part of the normal aging process and occurs in most people above 70.
In some individuals the PVD is incomplete, meaning the vitreous doesn’t completely separate from the retina. Part of the vitreous remains attached to the macula in the middle of the retina. It causes tugging and pulling on the macula that can lead to anatomical damage and loss of vision. This condition is known as vitreomacular traction (VMT) syndrome.
Also Known As
Causes and Risk Factors
Age-related degeneration of the vitreous humor causes pockets of fluid to form within the vitreous. It leads to contraction and decrease in volume of the vitreous. The separation of the humor from the retina happens because of vitreous liquefaction, and the front-back pulling and tugging forces that stretch the macula over time.
It weakens the attachment of the membrane of the retina and vitreous cortex and can cause semi-detachment of the posterior hyaloid membrane. This process leads to posterior vitreous detachment and can create VMT.
Vitreomacular traction risk factors include:
- Diabetic retinopathy
- Extreme nearsightedness
- Diabetic macular edema
- A blockage of veins in the retina
- Wet age-related macular degeneration (AMD)
- Older adults due to age-related vitreous changes
- Older women because of vitreous liquefaction linked to declining postmenopausal estrogen levels
Signs & Symptoms
VMT may show no symptoms. The common symptoms include:
- Reduced sharpness of vision
- Seeing flashes of light in the eye
- Objects appearing as smaller than their actual size
- Distorted visions which cause a grid of straight lines to appear blank, wavy or blurred
The symptoms may also be a sign of another eye disease, and it is essential to see an eye care professional for an evaluation. He/she will review the patient’s medical history and conduct a comprehensive eye exam. They may perform the following tests:
- Slit lamp exam to look at the inner eye structures
- Optical coherence tomography which helps to establish the damage to the macula
- A dynamic B-scan ultrasound which allows for a detailed examination of the vitreoretinal interface
- Fluorescein angiography – It enables the professional to see the circulation of blood in the retina and to identify inflammation of the macula, a common feature in VMT
Treatment is aimed at relieving traction and preserving vision.
The mode of treatment depends on the severity of the disease.
The wait and see or observation approach is adopted where vitreomacular traction is mild. In these cases, VMT doesn’t affect vision and treatment is not necessary.
There are cases where VMT goes away on its own without active intervention. The eye doctor may recommend regular checks. The patient may also be asked to track their vision daily at home with the Amsler grid.
The eye doctor may prescribe medication in the advanced incidences of the disorder. Medicine is also the treatment option for severe cases of vitreomacular traction where surgery is not viable. The eye doctor may administer Intravitreal injections that help to dissolve the protein fibers that link the vitreous to the macula.
Surgery helps to relieve the traction that damages the macula. A procedure known as vitrectomy is the recommended treatment option in severe VMT cases. These can cause sight-threatening retinal disorders such as:
- Creation of a hole in the macula (macular hole)
- Swelling of the macula (cystoids macular edema)
- Development of a macula scar tissue that distorts vision (macular pucker)
Vitrectomy can peel off scar tissue and restore the macula to its natural, lying flat shape. The surgeon can also replace the vitreous humor with a saline fluid or a temporary gas bubble.
Vitreomacular traction can be a severe condition that leads to vision loss. It can cause many disorders in the macula area. Often, these maculopathies are linked to ocular complications such as distorted vision and decreased vision.
VMT is treatable.
Regular moderate exercise and a healthy diet rich in fruit and vegetable may help people to maintain healthy eyes for longer. Routine eye checkups can identify early signs of vitreomacular traction.