A macular hole is a small hole in the macula which is in the centre of the retina. The macula is the part of the retina which is responsible for our sharp, detailed, central vision. This is the vision we use when we are looking directly at things, when reading, sewing or using a computer.
Macular holes usually only affect one eye, though there is a 10 per cent, one in ten, chance that the other eye will eventually be affected.
No one knows exactly why a macular hole develops in some people and not in others. As we get older the vitreous, the jelly in our eyeball becomes less firm and moves away from the back of the eye. When this happens the space left behind fills with aqueous fluid, a water-like substance produced by the eye. Usually the vitreous changing causes no problems to vision, but in some people the vitreous jelly is firmly attached to the retina over the macular area. As the vitreous shrinks it can pull on the macula. This can cause a small tear to develop and this is the start of a macular hole.
People with a macular hole will have changes in the central part of their vision. These changes can range from straight lines looking wavy in the early stages to a small blank
patch in the centre of vision in the late stages. People may first notice that they have trouble reading small print or that there is distortion when they look at a printed page.
There are a number of different stages to a macular hole. This is important to know because in the early stages it is possible for macular holes to heal themselves. This means that sometimes an ophthalmologist will want to monitor the progression of a macular hole before recommending any treatment.
However in most cases as a macular hole develops it will distort vision. In the final stages of a macular hole most central vision will be lost.
Macular hole surgery attempts to stop the macular hole developing to this stage.
An operation can be performed to help limit the sight problems a macular hole causes. The macula needs to lie flat on the back of the eye to receive, through blood vessels, all the nourishment it needs to work properly. If this is successful then often sight can be improved.
There are two main stages to the treatment:
Surgery for macular hole
The operation can be performed under local anaesthetic. Using micro surgical instruments the surgeon removes the vitreous jelly in your eye. This leaves a space inside the eye into which gas bubble is inserted. The gas helps the macular hole heal. This gas is lighter than air so it floats upwards and acts like a bandage pressing the macula hole flat onto the back of the eye, repairing the hole.
To make sure that the gas is putting pressure on the correct part of the retina, it is usually necessary for the patient to have their head positioned face downwards. The gas puts a small amount of pressure on the macular hole which encourages the hole to close and repair itself.
The correct posture is important because it makes sure that the pressure is applied in the right place. This part of the process is often just called "posturing".
This is required for 5 days following surgery but only during the daytime. At night you may sleep normally.
Posturing is very important. Managing it well can help the results of the operation on vision. If the gas does not put pressure on the correct part of the retina, the macular hole could continue to develop
During this time the gas bubble is slowly getting smaller so that eventually it is no longer in the eye. As this happens the space that was taken up by the gas is filled with aqueous fluid - the natural fluid made by the eye.
In most people there is improvement in vision following the surgery and recovery may continue for up to 12 months. However in others the operation's main effect is to stop the sight becoming any worse.
Staying face down for a long time can be difficult. It may be made more difficult if someone has other problems such as arthritis. It is important to discuss any other medical problems that may affect your ability to posture with your ophthalmologist.