GPs are often asked to check the eyes. It is difficult. First, there are no formal trainings for GPs to deal with eye problems. Second, we don't have the equipments which are often required for a proper eye examination, such as a slit lamp.
This post is to deal with some of the common eye problems and emergencies which could present to GP clinic or appear in the exam. John Murtagh's general practice book has two chapters on this topic, sydney eye hospital published an eye manual on how to deal with common eye emergencies, victoria eye hospital also published 35 golden eye rules to help GPs.
This post may be a little bit long but I am hoping to make this the only post a GP registrar needs to read for the exam and daily practice.
As with most things in medicine, history and examination are the key. In Murtagh, there is a section called questions directed to specific symptoms. It is a bit too simplistic but give some basic structure to what questions need to be covered during history taking.
- Presence of floaters --> normal ageing (esp.>55) with posterior vitreous detachment or may indicate haemorrhages or choroiditis
- Flashing lights --> normal ageing with posterior vitreous detachment or indicates traction on the retina
- Coloured haloes around lights --> glaucoma, cataract
- Zigzag lines --> migraine
- Vision worse at night or in dim light--> retinitis pigmentosa, hysteria, syphilitic retinitis
- Headache --> temporal arteritis, migraine, benign intracranial hypertension
- Central scotomata --> macular disease, optic neuritis
- Pain on moving eye --> retrobulbar neuritis
- Distortion, micropsia, macropsia --> macular degeneration
Diseases/disorders to exclude or consider
- DM
- Giant cell arteritis
- Hypopituitarism
- Cerebrovascular ischaemia/carotid artery stenosis
- MS
- Cardiac disease
- Anaemia
- Marfan syndrome (subluxated lenses)
- Malignancy (the commonest cause of eye malignancy is melanoma of the choroid)
Examination. In ophthalmology, there are three vital signs. Visual acuity, Pupils and Tonometry. I am not sure how many GP clinics have a tonometry (my clinic does not), so I have a very low threshold of referring people to ophthalmologist or optometrist. A proper examination should at least include the following:
- visual acuity
- pupil reacitons
- confrontation fields
- colour vision
- amsler grid
- fundus examination with dilated pupil
Common conditions that result in visual loss:
- Central retinal artery occlusion
- Central retinal vein thrombosis
- Retinal detachment
- Vitresous haemorrhage
- Macula degeneration
- Temporal arteritis
- Retinal migraine
- Posterior vitreous detachment
- Optic neuritis
Common eye conditions that can cause red and tender eye :
- Conjunctivitis (bacterial, viral or allergic)
- Glaucoma
- Uveitis
- Corneal ulcer
- Herpes simplex keratitis
- Microbial keratitis (e.g. fungal, amoeba and bacterial)
- Herpes oster ophthalmicus
- Penetrating injury
- Endophthalmitis
- Orbital cellulitis
- Scleritis/Episcleritis
- Blepharitis
- Foreign body
Red Flags
- Beware of unilateral red eyes
- Irritated eyes are often dry
- Never use steroids if herpes simplex is suspected
- A penetrating eye injury is an emergency
- Consider an intra-ocular foreign body
- Beware of herpes zoster ophthalmic if the nose is involved
- Irregular pupils: think iritis, injury and surgery
- Never pad a discharging eye
- Refer patients with eyelid ulcers
- If there is a corneal abrasion look for a foreign body
References:
John Murtagh
Sydney eye hospital: eye manual
Victoria eye hospital: 35 golden eye rules
