We will be discussing macular holes this month.
What is a macular hole?
A macular hole occurs when there is a disruption of the layers in the retina, specifically in the macula.
What are the causes and risk factors for developing a macular hole?
Macular holes usually develop gradually. The most common cause is changes in the gel of the back of the eye, the vitreous. Normally, the gel shrinks as we age and becomes more liquified. If the gel sticks to the retina, it can pull on it as it shrinks. This can create a macular hole. It is most common in people aged 50-70. Certain conditions can promote the formation of a hole including injury to the eye, high myopia (nearsightedness), diabetes, epiretinal membranes, and retinal detachments.
What are the symptoms?
The most common symptom is blurry central vision. One may notice dark spots or missing areas in the vision. Distortions in the vision and difficulty with fine details can also occur.
How is a macular hole diagnosed?
A comprehensive exam including checking the vision and dilating the eyes is needed to diagnose a macular hole. The dilated exam allows doctors to look at the macula.
An optical coherence tomography (OCT) photo also helps to see the break in the normal layers of the retina. The photo below shows a normal OCT photo of the macula. There is no break in the layers.
The arrow in this photo shows the break in the macula which is the macular hole.
How are these treated?
Occasionally, the holes can close by themselves. If they are very small and have minimal impact on vision, doctors will observe them for any changes. Surgery may be required to improve the vision. A vitrectomy is done to remove the vitreous, and therefore remove the risk of this gel pulling more on the retina. When the vitreous is removed, it is replaced by a gas bubble that helps the macula heal. The results of the surgery differ from patient to patient. Patients who have a macular hole for a shorter amount of time (less than six months), tend to have better results. Surgery should be discussed with the doctor to ensure that this is the best option.
Return next month for a new topic!
- Image courtesy of Nisha Gupta, MD [return]