Cataracts are very common, and so are encountered regularly in practice. It is, therefore, helpful for the optical assistant (OA) to have some knowledge and understanding of them as patients may ask questions about them. Remember that you should only answer questions that you are comfortable with and, if at all unsure, you should refer to a more senior, qualified colleague.
Cataracts are usually age-related, although they can be congenital. They may also be caused by trauma, diabetes, certain medications and some medical conditions. This article will focus on age-related cataracts as they are the most common type.
What are cataracts?
The crystalline lens in the eye is transparent, but cataracts cause the lens to become cloudy. Cloudy patches can form in different parts of the lens, and if they form in the centre, this is often the most troublesome to the patient.
Patients may complain of their vision being blurred or misty, and some may say that they feel their glasses need cleaning all the time. Patients may also complain of light sensitivity and glare, which can be caused by the cataract scattering the light within the eye. Other symptoms include seeing halos around lights, and colours seeming dull, or yellowish. Cataracts usually develop in both eyes, although may develop at different rates in each eye.
Age-related cataracts
Age-related cataracts usually develop quite slowly and, in the early stages, an update to the prescription may be sufficient for the patient. Often, cataracts cause an increase in myopia as the lens becomes denser (you may have heard the term ‘myopic shift’). This means long-sighted patients see a decrease in their prescription and will sometimes say they can see better if they take their glasses off.
Myopic patients, however, will say their vision is getting worse. If glare is a problem for the patient, sunglasses can be beneficial, as can be a wide-brimmed hat or cap, to shield the eyes from the sun. The patient may need more frequent eye examinations than usual whilst cataracts are developing, if the prescription is changing.
When the cataracts affect the patient’s quality of life, then referral may be needed, so long as the patient consents to a referral. Waiting times do vary considerably between different parts of the country, and so it is a good idea to be familiar with the waiting times in your area. Patients can always choose to pay privately, which will usually mean a shorter waiting time.
Nowadays, there are independent sector providers who undertake cataract surgery funded by the NHS, so the patient doesn’t need to pay and may be seen more quickly than within the NHS.
Cataract surgery
Cataract surgery is usually a safe and effective procedure, although all operations carry a risk. The risk is comparatively low for cataract removal, but complications can occur in a small percentage of patients and may include infection and, very rarely, retinal detachment.
The crystalline lens is contained within the lens capsule, and the operation to extract the cataract involves removing the crystalline lens but leaving the lens capsule in place. The procedure is usually conducted under a local anaesthetic and the eye is held open during the procedure with retractors.
A very small incision is made, and a process called phacoemulsification is used to break up and remove the cloudy lens. Once the lens has been removed, an artificial lens is put in place, and held within the lens capsule. This is called an intraocular lens, or IOL. The process takes about 30 minutes in total, and the patient can go home the same day with prescribed eye drops they must use. Vision will be blurry at first but should improve within a few days.
Patients will need to attend for a ‘cataract follow-up appointment about four to six weeks after surgery – and this is often provided in optical practices. This is different from a routine sight test – although they may also need to have one of these and get new spectacles as their prescription will have changed.
Most patients are delighted with the results and say their vision is better than it has been for a long time. Many report colours seem brighter and more vivid too.
So next time a patient asks you to explain cataract to them, hopefully you will be able to answer some of their questions.
Sue Deal FBDO R is a practising dispensing optician, ABDO College examiner, senior tutor and supervisor for dispensing opticians. She is also a practice visitor and external moderator for ABDO. She was recently awarded the ABDO Medal of Excellence for her outstanding services to the profession.