The eye in general medicine

The integrity of ocular anatomy and physiology, the function of the visual system, and the perception of vision, our most prized sense, are intimately connected with our general health. Subtle visual signs and symptoms may therefore be the first manifestation of occult systemic disease. With a basic history and examination of the eyes and vision, the physician can narrow the differential diagnosis and ascertain whether there is any immediate threat to vision or even life. The major focus of this chapter is the eye in the context of a range of vascular, haematological, neoplastic, inflammatory, endocrine, genetic, metabolic, toxic, and nutritional disorders. This chapter also considers the leading causes of blindness globally, and common ocular presentations in primary care and general medical practice. Other isolated ocular conditions are excluded and neuro-ophthalmological conditions are referred to elsewhere in this book (Chapters 24.6.1 and 24.6.2).