• Associated symptoms, such as vomiting, photophobia, neck pain, visual disturbance.

• Relevant family history.

Summarise your findings

This 32-year-old woman’s headache began gradually last night and is worse today; she has been in bed in a darkened room, trying to sleep. She has

vomited the analgesia she took. She often has headaches at the time of her period but this is the worst headache she has ever experienced. She

recalls having one or two migraines as a child, and her mother had migraine. She is otherwise well and takes no medication other than the oral

contraceptive. The examination is normal, although she looks tired and distressed.

Suggest a differential diagnosis

The most likely diagnosis is migraine; the headache evolved and worsened over a few hours, with no ‘red flags’, on a background of a predisposition

to migraine. The differential includes more sinister causes such as meningitis, cerebral venous sinus thrombosis or intracranial haemorrhage, but there

are no features to support these. The headache is likely to resolve in the next day or two.

Suggest initial investigations

She does not need any tests, as there are no features to suggest she needs brain imaging or lumbar puncture to exclude a subarachnoid haemorrhage

or meningitis.

the investigation of epilepsy, encephalopathies or dementia.

Modifications to standard EEG improve sensitivity and include

sleep-deprived studies, prolonged videotelemetry and invasive

EEG monitoring.

Electromyography (EMG) involves needle electrodes inserted

into muscle. Electrical activity is displayed on an oscilloscope

and an audio monitor, allowing the neurophysiologist to see and

hear the pattern of activity. Neurogenic and myopathic pathology

causes characteristic EMG abnormalities.

Nerve conduction studies involve applying electrical stimuli

to nerves and measuring the speed of impulse conduction.

They are used for both motor and sensory nerves, and are

helpful in diagnosing peripheral nerve disorders such as nerve

compressions or polyneuropathies. They are also helpful is

distinguishing between axonal and demyelinating neuropathies,

the underlying causes and management of which are very

different.

OSCE example 2: Tremor

Mr Anderson, 76 years old, presents with a tremor of his arm.

Please examine his arms

• Introduce yourself and clean your hands.

• Observe the patient sitting at rest; note any tremor, abnormal postures, facial expression, jaw/chin tremor, drooling.

• Listen to his speech.

• Ask him to raise both arms above his head, then to stretch them out in front of him; observe any tremor on posture.

• Ask him to perform piano-playing movements; look carefully for asymmetry and reduced fine finger movements.

• Assess tone, looking specifically for asymmetry, and cog wheeling or lead pipe rigidity in the affected right arm.

• Test power in shoulder abduction, elbow flexion/extension and finger extension.

• Test upper limb deep tendon reflexes (biceps, supinator and triceps).

• Omit sensory testing, as this is unlikely to add anything.

• Test finger-to-nose movements.

• Ask him to walk, observing what happens to the tremor and right arm swing.

• Thank the patient and clean your hands.

Continued

150 • The nervous system

Integrated examination sequence for the nervous system

A complete neurological examination is demanding for both doctor and patient, and in many cases will not be necessary. The history will dictate a

more targeted examination, and time spent on the history is always more productive than an amateur neurological examination.

Cranial nerve examination

• 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).

• Observe both eyes in the neutral position. Are they orthotropic (both pointing in the same direction)? Test eye movements, observing

for completeness of movement in pursuit and looking for nystagmus (III, IV, VI).

• Test facial sensation (V) and corneal reflex (V and VII).

• Observe for facial asymmetry and test facial muscles of the upper and lower parts of the face (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

• Expose the upper limbs ensuring maintenance of dignity and privacy; request a chaperone if appropriate.

• Inspect for wasting, fasciculations.

• As a screening test ask the patient to hold the arms out (palms up) and close their eyes – watch for pronator drift.

• Assess tone.

• Test muscle power: shoulder abduction (axillary nerve C5), elbow flexion (musculocutaneous nerve, C5, C6) and extension (radial nerve, C7), finger

extension (posterior interosseus nerve, C7), index finger abduction (ulnar nerve, T1), little finger abduction (ulnar nerve, T1), thumb abduction

(median nerve, T1).

• 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

• Undress the patient to expose both lower limbs fully, ensuring maintenance of dignity and privacy; request a chaperone if appropriate.

• Carry out a general inspection, noting walking aids and other associated neurological signs, such as facial droop or ipsilateral arm flexion.

• If the patient is able to do so, ask them to stand and walk so that you can assess stance and gait. Assess tandem gait.

• Inspect both legs, noting any scars, muscle wasting or fasciculations, abnormal postures or movements.

• Assess tone at the hip, knee and ankle. Test for ankle clonus.

• Test muscle power. As a simple screen, assess hip flexion (iliofemoral nerve, L1, 2) and extension (sciatic, L5/S1), knee flexion (sciatic, S1) and

extension (femoral, L3, 4), and ankle plantar flexion (tibial, S1, 2) and dorsiflexion (deep peroneal, L4, 5).

• Assess reflexes at the knee (L3) and ankle (S1), comparing sides. Test the plantar response.

• Test coordination via heel-to-shin tests.

• Test sensory modalities: pinprick, temperature, vibration and joint position sense. Map out any symptomatic areas of disturbed sensation.

OSCE example 2: Tremor – cont’d

Summarise your findings

The patient has an asymmetric pill-rolling rest tremor of the right arm, which briefly disappears on movement but quickly returns (re-emergent tremor).

He also has a tremor affecting the jaw/chin. There is a lack of facial expression, drooling, monotonous, hypophonic speech, bradykinesia (reduced fine

finger movements, difficulty with repetitive movements), increased tone with cog wheeling, and loss of the right arm swing and increased tremor when

walking, with short stride length.

Suggest a diagnosis

These findings are typical of Parkinson’s disease.

Suggest initial investigations

A diagnosis of Parkinson’s disease is usually based on the clinical features and investigation unnecessary. In selected cases, structural imaging (MR or

CT) to rule out the rare mimics of PD, or functional imaging (DaTscan) may be appropriate. Blood tests are rarely helpful, but a strong family history

may precipitate consideration of genetic testing.

8

The visual system

Shyamanga Borooah

Naing Latt Tint

Anatomy and physiology 152

Eye 152

Extraocular muscles 152

Refractive elements of the eye 153

Visual pathway 153

Pupillary pathways 153

The history 155

Common presenting symptoms 155

Past ocular history 159

Past medical history 159

Drug and allergy history 159

Family history 159

Social history 159

The physical examination 160

General examination 160

Visual acuity 160

Orbit and periorbital examination 161

Pupils 161

Visual fields 162

Ocular alignment and eye movements 163

Ophthalmoscopy 164

Retinopathies 165

Investigations 165

OSCE example 1: Gradual visual loss 168

OSCE example 2: Double vision 169

Integrated examination sequence for ophthalmology 169

152 • The visual system

Eye

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