What is an aphakic patient?

A person who has had his lens removed, usually following a cataract operation is termed as an aphakic. The power of spectacle lens to compensate the removed lens is around +12 to +14.

Why should an aphakic patient wear contact lenses?

An aphakic patient who has had a lens removed from one eye has a very real problem. If he wears spectacles on the eye which has been operated, with the big plus number, he sees a big image, while the other unoperated eye sees a normal image. If he looks at a bus, he sees a small bus in the centre of a big bus. He has the alternative of (a) either not wearing glasses over his operated eye or (b) using a glazed glass over his unoperated eye. If he wishes to use both eyes, he has to use a contact lens to match the images. For him it is not an option, it is a necessity.

What problems of high plus-powered spectacle lenses are relieved by wearing contact lenses?

Big plus power spectacle lenses have their own problems.

(a) Magnification effect: Objects seem nearer than they really are. Here, walking on the road, crossing a kerb and eating at a dining table are the usual problems.

(b) Curvature effect: Straight lines appear curved. A door seems to bulge in the middle and be narrow at the top.

(c) Reduced visual field: The field of vision with thick spectacle lenses is markedly reduced. Because of the prismatic or bending effect of these thick lenses, objects seem to pop in and out like a jack-in-the-box.

(d) Unsightly appearance: Thick lenses are usually equated with weak eyes. It's a problem for a man or woman who has to hold a job.

All these problems are removed by contact lenses which restore near normal sight.

Can an aphakic patient wear contact lenses comfortably?

An aphakic patient is very comfortable with contact lenses.

When can an aphakic patient wear lenses comfortably?

Usually 3 months after surgery, with hard lenses. Soft lenses, though, can be started much earlier, at about 6 weeks, as there is no bumping of the lens against the suture line.

Can an aphakic patient wear soft lenses?

Usually an aphakic patient is fitted with hard lenses as a certain degree of astigmatism is common immediately after surgery. This astigmatism tends to decrease with time. If the astigmatism is absent or decreases to a low level, soft lenses can certainly be worn.

Bianca Cohen

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