Macular Hole

A macular hole is a small microscopic break in the macula which is located in the back of the eye.  Patients with a macular hole will have reduced vision in that eye however it may go unnoticed as the healthy eye will compensate for the poor vision of the affected eye.  In order to see clearly, light from an object has to be focused by the optical elements of the eye onto the light-sensitive tissue called the retina.  The macula is the small part at the centre of the retina which provides the sharp, central vision we need for reading, driving, and seeing fine detail.

Age is a contributing factor in the development of a macular hole as it increases in patients over 60 years of age, and is more common in women.  Patients with a macular hole have a 10% - 15% chance of developing a hole in the other eye.

There are three distinct stages to a macular hole:

• Stage 1 - Foveal detachment.  Without treatment, about half of Stage 1 macular holes will progress into stage 2
• Stage 2 –Small full-thickness holes.  Without treatment, about 70 percent of Stage 2 macular holes will progress into larger holes over 6-12 months
• Stage 3/4 – Larger Full-thickness macular hole.  The size of the hole and its location on the retina determine how much it will affect a person's vision. When a Stage 3 macular hole develops, most central and detailed vision can be lost. If left untreated, a macular hole may lead to a retinal detachment, a sight-threatening condition that requires immediate medical attention.

What causes a Macular Hole?
Most of the eye's interior is filled with vitreous, a gel-like substance that fills about 80 percent of the eye and helps it maintain a round shape.  It consists of 99% of a watery substance constantly produced by the ciliary body and the other 1% contains millions of fine fibres that are attached to the surface of the retina.  They are extremely springy/ elastic and give full expanse within the eye.  They give the vitreous fluid the gelatinous form in the posterior chamber of the eye.  As we age the vitreous slowly shrinks and pulls away from the retinal surface.  Natural fluids will fill the area where the vitreous has contracted, which is normal.  However, if the vitreous is firmly attached to the retina when it pulls away, it can cause a small tear on the macula.  Once the vitreous has pulled away from the surface of the macula, some of the fibres can remain attached and can contract.  This increases tension and can lead to a macular hole.  Macular holes can also occur from eye disorders, such as high myopia (nearsightedness), macular pucker, and retinal detachment; eye disease, such diabetic retinopathy and Best's disease; and injury to the eye.