• Ask about sense of smell and taste (I).
• Assess visual acuity (using a Snellen chart) and visual fields (by confrontation) (II).
• Observe pupils and test pupillary reactions bilaterally: direct and consensual (II).
for completeness of movement in pursuit and looking for nystagmus (III, IV, VI).
• Test facial sensation (V) and corneal reflex (V and VII).
• Perform a bedside test of hearing (VIII).
• Assess speech, swallow and palatal movement (IX, X, XI).
• Inspect the tongue and assess movement (XII).
Neurological examination of the upper limb
• Inspect for wasting, fasciculations.
• Assess reflexes at biceps (C5), triceps (C7) and supinator (brachioradialis, C6).
• Test coordination with finger – nose test and look for dysdiodokinesia.
• Test sensory modalities: pinprick, temperature, vibration sense, joint position sense.
Neurological examination of the lower limb
• Assess tone at the hip, knee and ankle. Test for ankle clonus.
• Assess reflexes at the knee (L3) and ankle (S1), comparing sides. Test the plantar response.
• Test coordination via heel-to-shin tests.
OSCE example 2: Tremor – cont’d
walking, with short stride length.
These findings are typical of Parkinson’s disease.
Suggest initial investigations
may precipitate consideration of genetic testing.
Refractive elements of the eye 153
Common presenting symptoms 155
Orbit and periorbital examination 161
Ocular alignment and eye movements 163
OSCE example 1: Gradual visual loss 168
OSCE example 2: Double vision 169
Integrated examination sequence for ophthalmology 169
The eyeball is approximately 25 mm in length and comprises
three distinct layers. From outside in (Fig. 8.1), these are the:
• Outer fibrous layer: this includes the sclera and the clear
cornea. The cornea accounts for two-thirds of the
refractive power of the eye, focusing incident light on to
• Middle vascular layer (uveal tract): anteriorly this consists
of the ciliary body and the iris, and posteriorly the choroid.
• Inner neurosensory layer (retina): the retina is the structure
responsible for converting light to neurological signals.
The six extraocular muscles are responsible for eye movements
(Fig. 8.2). Cranial nerve III innervates the superior rectus, medial
rectus, inferior oblique and inferior rectus muscles. Cranial nerve
IV innervates the superior oblique muscle and cranial nerve VI
innervates the lateral rectus muscle. The cranial nerves originate
The eye is a complex structure situated in the bony orbit. It is
protected by the eyelid, which affords protection against injury
as well as helping to maintain the tear film. The upper lid is
elevated by the levator palpebrae superioris, innervated by cranial
nerve III, and Müller’s muscle, innervated by the sympathetic
autonomic system. Eyelid closure is mediated by the orbicularis
oculi muscle, innervated by cranial nerve VII.
The orbit also contains six extraocular muscles: the superior
rectus, medial rectus, lateral rectus, inferior rectus, superior
oblique and inferior oblique. In addition, the orbit houses the
lacrimal gland, blood vessels, autonomic nerve fibres and cranial
nerves II, III, IV and VI. The contents are cushioned by orbital
fat, which is enclosed anteriorly by the orbital septum and the
The conjunctiva is a thin mucous membrane lining the posterior
aspects of the eyelids. It is reflected at the superior and inferior
fornices on to the surface of the globe. The conjunctiva is coated
in a tear film that protects and nourishes the ocular surface.
Levator palpebrae superioris muscle
Fig. 8.1 Cross-section of the eye and orbit (sagittal view).
Fig. 8.2 Control of eye movements. The direction of
displacement of the pupil by normal contraction of a particular
muscle can be used to work out which eye muscle is paretic. For
example, a patient whose diplopia is maximal on looking down and
to the right has either a weak right inferior rectus or a weak left
of Budge at the level of T1. Fibres then pass to, and synapse
in, the superior cervical ganglion before joining the surface of
the internal carotid artery and passing to the pupil along the
nasociliary and the long ciliary nerves (Fig. 8.6B).
in the midbrain and pons and then pass through the cavernous
Refractive elements of the eye
The major refracting elements of the eye are the tear film, the
cornea and the crystalline lens. The cornea possesses the greatest
refractive power and is the main refracting element of the eye;
the lens provides additional controllable refraction, causing the
light to focus on to the retina. When light is precisely focused on
to the retina, refraction is called emmetropia (Fig. 8.4A). When
the focus point falls behind the retina, the result is hypermetropia
(Fig. 8.4B, long-sightedness). When rays focus in front of the
retina, the result is myopia (Fig. 8.4C, short-sightedness). These
refractive errors can be corrected with lenses or with a pinhole
The visual pathway consists of the retina, optic nerve, optic
chiasm, optic tracts, lateral geniculate bodies, optic radiations
and visual cortex (Fig. 8.5). Deficits in the visual pathway lead
The pupil controls the amount of light entering the eye. The
intensity of light determines the pupillary aperture via autonomic
reflexes. Pupillary constriction is controlled by parasympathetic
nerves, and pupillary dilatation is controlled by sympathetic
For pupillary constriction, the afferent pathway is the optic
nerve, synapsing in the pretectal nucleus of the midbrain. Axons
synapse in both cranial nerve III (Edinger–Westphal) nuclei, before
passing along the inferior division of the oculomotor nerve to
synapse in the ciliary ganglion. The efferent postganglionic
fibres pass to the pupil via the short ciliary nerves, resulting in
For pupillary dilatation, the sympathetic pathway originates
in the hypothalamus, passing down to the ciliospinal centre
Internal carotid arteries Abducens nerve
Fig. 8.3 Cavernous sinus (coronal view). Neuroanatomy of cranial nerves III, IV and VI.
Fig. 8.4 Normal and abnormal refraction by the cornea and lens.
A Emmetropia (normal refraction). Cornea and lens focus light on the
retina. B Hypermetropia (long-sightedness). The eye is too short and the
image on the retina is not in focus. A convex (plus) lens focuses the image
on the retina. C Myopia (short-sightedness). The eye is too long and the
image on the retina is not in focus. A concave (minus) lens focuses the
image on the retina. D Myopia corrected using a pinhole. This negates
the effect of the lens, correcting refractive errors by allowing only rays from
Fig. 8.6 Pupillary innervation. A Parasympathetic pathway.
The eye is covered in a network of vessels in the conjunctiva, episclera
and sclera. Ciliary vessels are also found around the cornea. Dilatation
or haemorrhage of any of these vessels can lead to a red eye.
Additionally, in uveitis, acute angle-closure glaucoma and corneal
irritation the ciliary vessels around the cornea become more prominent
(a ‘ciliary flush’). The appearance is distinct from conjunctivitis, in
which there is a relative blanching of vessels towards the cornea.
• if the eye is painful or photophobic
• if there has been any recent trauma
• whether there is any discharge
• whether there has been any recent contact lens wear or
Box 8.4 summarises the features of the common causes of
a red eye on history and examination.
Decipher whether the diplopia is monocular or binocular. Binocular
diplopia is caused by an imbalance in eye movement. Monocular
diplopia results from intraocular disease in one eye. There are
several causes of double vision (Box 8.5 and Figs 8.9 and 8.10).
• whether the double vision occurs in one or both eyes
• about the character of the double vision, and whether the images
are seen side by side, one above the other or at an angle
• whether the double vision is associated with any recent
Test the eye movements (see Fig. 8.11), and use your
knowledge of the function of the extraocular muscles (see Fig. 8.2)
to work out which cranial nerve is affected in binocular diplopia.
Increasing discharge from the eye results from either an increase
in production or a decrease in drainage from the ocular surface.
Irritation of corneal nerves activates cranial nerve V(I) and results
Tears normally drain through the punctum at the medial end of
the lower eyelid into the nasolacrimal duct, which opens below the
inferior turbinate into the nasal cavity. Blockage of tear drainage
or abnormal lid position can also result in excessive discharge.
• whether the discharge is clear or opaque
• whether there is associated pain, foreign body sensation
• whether the patient has noticed other abnormalities, such
There are many causes of eye discharge, and their clinical
features are summarised in Box 8.6.
The orbit is an enclosed structure, except anteriorly. Any swelling
inside the orbit can lead to proptosis or anterior displacement
• the swelling is unilateral or bilateral
• the changes were acute or gradual
• there is any itchiness or irritation
• the swelling is associated with any double vision.
Box 8.7 summarises the common causes of swollen eyes.
When taking an ophthalmic history, bear in mind the anatomy
of the eye and visual pathways. This will enable you to work
from ‘front to back’ to include or exclude differential diagnoses.
Start the ophthalmic history with open questions. This builds rapport
with the patient by allowing them to describe the condition in their
own words, and provides clues for more directed questions later.
The visual system has its own set of presenting symptoms,
which prompt specific sets of questions. The most common
Vision may be altered by an intraocular disease that leads
to a change in the optical or refractive properties of the eye
and prevents incident light rays from being clearly focused on
the retina. Alternatively, it may result from extraocular factors
associated with damage to the visual pathway, which runs from
the optic nerve to the occipital lobe (see Fig. 8.5).
Establish whether the change in vision is sudden or gradual,
as these will have their own specific set of differential diagnoses
(Box 8.1 and Fig. 8.7; Box 8.2 and Fig. 8.8).
Vision may be not just reduced but also distorted. This
results from disruption to the normal structure of the macula,
the central part of the retina. The most common cause is macular
degeneration but it may also frequently stem from an epiretinal
membrane, vitreous traction or central serous retinopathy.
Flashes and floaters result from disturbance of the vitreous and
gradually degenerates and liquefies, causing it to peel off from the
retina. The vitreous is attached to the retina in certain regions; in
these regions the vitreous either detaches with traction, resulting
in flashing lights, or detaches by tearing the retina, releasing
retinal pigment cells. Patients will see either of these as floaters.
Haloes are coloured lights seen around bright lights. They
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