Nicholas R. Galloway

Systemic Disease and the Eye

Diabetes mellitus is an important cause of blindness: about 1000 people are registered blind from diabetes per year in the United Kingdom. Most of these patients are elderly, but diabetes is the commonest cause of blindness in young people in this country. The management of diabetic eye disease has improved greatly over the past 10 years so that much of this blindness can now be prevented. In spite of this, most general practitioners are aware of tragic cases of rapidly progressive blindness in young diabetics. The more serious manifestations of diabetes in the eye tend to affect patients in the prime of life. The tragedy is even greater when one considers that this blindness is largely avoidable.

Common Diseases of the Conjunctiva and Cornea

This is common and tends to occur spontaneously or sometimes after straining or, especially, vomiting. The eye becomes suddenly red and although the patient may experience a slight pricking, the condition is usually first noticed in the mirror or by a friend. The haemorrhage gradually absorbs in about ten days and investigations usually fail to reveal any underlying cause. Very rarely, it is necessary to cauterise the site of bleeding if the haemorrhage is repeated so often that it becomes a nuisance to the patient (Fig. 5.1).

Tumours of the Eye and Adnexae

In this chapter the more important ocular tumours will be considered. There are a considerable number of other rare tumours and the interested student should refer to one of the more specialised and comprehensive textbooks of ophthalmology for further reading.

The Red Eye

Redness of the eye is one of the commonest signs in ophthalmology, being a feature of a wide range of ophthalmological conditions, some of which are severe and sight threatening whereas some are mild and of little consequence. Occasionally the red eye may be the first sign of important systemic disease. It is important that any practising doctor has an understanding of the differential diagnosis of this common sign, and a categorisation of the signs, symptoms and management of the red eye will now be made from the standpoint of the non-specialist general practitioner.

Long Sight, Short Sight

When the patient with an ophthalmological problem first enters the doctor’s surgery, it is useful to notice whether he or she is long sighted or short sighted. The long-sighted person tends to have smaller eyes than normal, whereas the short-sighted person tends to have larger eyes than normal. Sometimes this is evident on inspection of the eyes and eyelids, but the long-sighted person will usually be wearing convex or converging lenses and these tend to make the eyes look bigger, whereas the short-sighted person will be wearing concave lenses which make the eyes look smaller (Fig. 3.1).

The Scope of Ophthalmology

Those who regard science as the study of more and more about less and less will find that medicine is no exception to this process of specialisation. It is mainly by the intensive study of minutiae that studies can become effective and lead to the prevention and cure of disease. The eye and its surrounding structures provide us with an ideal terrain for this type of specialisation. The importance of the eye and its function in our daily lives is sometimes underrated, but a consideration of the part played by vision in our consciousness soon makes us realise the value of vision. If we think of dreams, memories, of photographs and of almost anything in our daily existence, it is difficult to express them without visual references. After a little careful consideration of the meaning of blindness, it is easy to sense the rational and irrational fears that our patients present in daily life. In a modern European community the effects of blindness are not so apparent as in former years, and blind people tapping their way around streets or begging for food are less in evidence to remind us of the deprivation which they suffer. This is due to the effective application of preventive medicine and to the efficacy of modern surgical techniques.

Basic Anatomy and Physiology of the Eye

This chapter describes the anatomy of the eyeball, the visual pathway, and the ocular adnexae. It also provides a basic introduction to the physiology and functioning of the eye.

Examination of the Eye

This chapter describes how to take an ophthalmological history and examine the eye. Various special instruments and techniques which are used in the eye department are described.

The Ageing Eye

The eye and its supporting structures undergo well known changes with age. As the population continues to age, it is important to distinguish ‘normal’ involutional changes from aging pathology of these structures. This chapter describes the standard age changes, as well as diseases that occur in the eye and its adnexae with age. These include cataracts, age-related macular degeneration, glaucoma and giant cell (or temporal) arteritis.

Common Diseases of the Eyelids

Quite often patients present at the clinic or surgery complaining of watering eyes. It may be the golfer whose glasses keep misting up on the fairways or the housewife who is embarrassed by tears dropping onto the food when cooking, or it may be the 6-month-old baby whose eyes have watered and discharged since birth. Sometimes an elderly patient may complain of watering eyes when on examination there is no evidence of tear overflow but the vision has been made blurred by cataracts. Some degree of tear overflow is quite normal in windy weather, and the anxious patient may over-emphasise this; it is important to assess the actual amount of overflow by asking the patient whether it occurs all the time both in and out of doors.