A standardized test such as the Mini-Mental State Examination (MMSE) can be used to test aspects of cognitive function. Although this was originally devised to be used as a screening tool for dementia, it is of some use for a brief cognitive overview.

Some criticisms of the MMSE are that the language and visuo-perceptual items are too easy, there is not a proper test of delayed recall, and there is no timed test to assess subcortical cognitive slowing. In an effort to address these issues, the Addenbrooke’s Cognitive Examination (ACE) includes the 30 points of the MMSE, but the additional 70 points improve the assessment of memory and language and include timed fluency tasks which are sensitive to subcortical dysfunction.

CRANIAL NERVE EXAMINATION

CRANIAL NERVE I (OLFACTORY NERVE)

The patient should be asked if taste and smell are affected. Further testing is not necessary unless the patient concurs or there is a special reason to test olfaction. Before testing, the airway should be checked that it is clear. Each nostril is tested with an odour such as camphor or peppermint. Loss of smell is termed anosmia. If nasal disease is excluded, a lack of smell may be due to closed head injury or anterior cranial fossa disease but is also a feature of certain neurodegenerative disorders such as Parkinson’s disease.

CRANIAL NERVE II (OPTIC NERVE)

The basic tools for assessment are a bright light, an ophthalmoscope, coloured pins, and a vision reading chart (e.g. Snellen). First assess visual acuity. The patient is asked if they are aware of reduced vision in either or both eyes. Visual acuity should be tested wearing glasses if prescribed. Each eye is covered in turn and its neighbour tested separately. When using the Snellen chart, the patient stands 3–6 m from the chart and reads from largest to smallest print, visual acuity being measured as the distance from the chart (3 or 6 m) over the distance at which the letters should normally be seen, e.g. 6/6 for normal and 6/60 for poor vision. Alternatively, a near vision chart is held 30 cm from the patient and again they are asked to read the smallest print possible with each eye in turn. Results are expressed as N6 and so on.

Visual fields testing requires a 7 mm coloured (red) pin. The patient is asked if they are aware of a gap or ‘blindspot’ in either eye and the clincian establishes that the red pin target is visible to each eye. The patient should then look into the examiner’s eyes, standing 1 m away. The field of vision of the examiner can then be compared with that of the patient (confrontation). The extent of visual field can be ascertained by testing each eye from each quadrant, asking the patient to state as soon as they can see the pinhead at all (regardless of colour). Whether the patient can see red in central vision should also be checked.

The following findings may be demonstrated:

Constricted fields of vision, e.g. chronic papilloedema, glaucoma, and functional illness (tunnel vision).

Central field defect (scotoma), e.g. optic neuritis, retinal haemorrhage.

Altitudinal (vertical) field defects in one eye, e.g. retinal infarction.

Hemianopia.

Bitemporal (defect in the temporal fields in both eyes), e.g. pituitary disease.

Homonymous (defect to the same side in both eyes), e.g. parietal, temporal, or occipital lobe disease.

Quadrantanopia, congruous, and incongruous field defects further localize defects (see page 104).

Fundoscopy

The ophthalmoscope is used to examine the fundus of each eye separately, while the patient fixates, in a darkened environment, into the distance. The ophthalmoscope should be adjusted for the clinician’s own vision. If myopic, the lens is turned anticlockwise (red), if long-sighted clockwise (black). The patient’s eye is then approached approximately 15° from the line of fixation and the disc, blood vessels, and retina are assessed and findings documented accordingly.

The student should be aware of the following fundoscopic findings:

Optic disc: normal, pale, swollen. Blood vessels: normal, attenuated, swollen,

nipped, absent, containing emboli, cholesterol.

Retina: infarcts, haemorrhages, exudate, retinopathy.

CRANIAL NERVES III, IV, AND VI (OCULOMOTOR, TROCHLEAR,

AND ABDUCENT NERVES)

These nerves are responsible for all eye movements. The clinician should inspect for ptosis (drooping eyelid), pupil size, strabismus (squint), and proptosis (protuberance of the globe of the eye). If proptosis is suspected, the eye should be inspected from above, tilting the head back to contrast the prominence of each eye. The pupil light reaction should be tested in each eye separately, checking both the direct (illuminated eye) and indirect (nonilluminated eye) responses. The pupils’ reaction to converging (when looking at the end of the nose the pupils constrict) should also be assessed. The patient should be asked if double vision is present; if so, confirmation that the double vision is binocular (requires both eyes to be present) can be obtained by covering one eye at a time. The patient should be asked whether the two images are separated vertically or horizontally, and in which direction the two images (true and false) maximally separate. The range of slow-pursuit horizontal and vertical eye movements is assessed by asking the patient to follow the clinician’s moving finger or similar object. If double vision is present, in which direction of gaze double vision is maximal should be determined.

The following rules help assessment: Double vision is worse (maximal) in the direction of the affected muscle.

The false image is always the outermost one. The false image is the product of the affected eye.

When evaluating eye movements:

The position of the head should be noted (patients with double vision will often tilt the head to minimize this).

The eyes should be checked in the primary position (at rest) and ptosis or pupillary asymmetry noted.

The eyes should be assessed following an object. Are abnormal movements (nystagmus) present? Is there paralysis of one or more muscles? All directions of gaze must be tested and knowledge of the specific muscle innervation is essential.

Nystagmus is defined as a slow drift of the eyes to one side with a fast corrective movement in the opposite direction. While physiological when watching an object moving rapidly by, these movements are generally abnormal and inform on the presence of brainstem/cerebellar disease.

The patient should be asked to follow a moving finger and any jerky movements observed. Nystagmus can be:

–Vertical. Upbeat: upper brainstem, e.g. pontine infarction. Downbeat: cervicomedullary junction, e.g. Arnold–Chiari malformation.

–Horizontal. Ataxic: greater in the abducting (looking outwards) rather than adducting (looking inwards) eye, e.g. multiple sclerosis.

–Multi-directional. Present in all directions of gaze (though maximal in one), e.g. druginduced.

–Unidirectional. Peripheral: labyrinthine disease. Central: unilateral cerebellar disease.

CRANIAL NERVE V (TRIGEMINAL NERVE)

The patient is asked if they are aware of altered facial sensation, and sensation of light touch with cotton wool is tested in each of the three sensory divisions (ophthalmic V1, maxillary V2, and mandibular V3). The corneal reflex (V1&V2) is tested with a wisp of cotton wool, touching cornea not sclera. Next, the three divisions are tested with a pin. When defining the territories of sensory loss, the clinician should always move from the abnormal to the normal.

Evidence of wasting (temporalis muscles) should be noted and motor function assessed. The pterygoids are tested with the jaw open wide (thus avoiding any minor deviation due to temperomandibular joint asymmetry), then jaw opening resisted by pressing against the joint. In order to test the jaw jerk, the patient is asked to let the jaw hang loosely open and a tendon hammer is used to percuss on the clinician’s finger placed on the patient’s chin.

CRANIAL NERVE VII (FACIAL NERVE)

The nasolabial folds (from the corner of the mouth to the sides of the nose) should be observed and spontaneous movements such as blinking and smiling noted. The following muscles are tested using the instructions described: frontalis: ‘wrinkle the forehead’; orbicularis oculi: ‘screw up the eyes’; buccinator: ‘blow out the cheeks’; and orbicularis oris: ‘show the teeth’. Ptosis (drooping of an eyelid) is not due to weakness of facial nerve muscles, and facial asymmetries without weakness is common so the clinician should not be misled. The patient should be asked about taste (absence or distortion) and tested with a sugar or salt solution applied by a cotton bud to the anterior two-thirds of the tongue.

The facial nerve also supplies the muscle to the stapedius and the parasympathetic supply to the lachrymal gland, though neither is tested at the bedside. Four types of disturbance are found:

Unilateral lower motor neurone, e.g. Bell’s palsy.

Bilateral lower motor neurone, e.g. myasthenia gravis.

Unilateral upper motor neurone, e.g. hemisphere stroke.

Bilateral upper motor neurone, e.g. brainstem stroke (pseudobulbar palsy).

Loss of emotional expression is a feature of Parkinson’s disease, while excessive emotional expression (emotional incontinence) occurs in pseudobulbar palsy.

Distinction between unilateral upper and lower motor neurone facial weakness is simple. In upper motor neurone (UMN) weakness, forehead and eye closure is relatively spared (bilateral supranuclear innervation) while these are affected with lower motor neurone (LMN) lesions (the final common pathway for all that travels to the facial nucleus).

CRANIAL NERVE VIII (AUDITORY AND VESTIBULAR NERVES)

Assessment requires a 256 or 512 Hz tuning fork and an auroscope. First, the patient is asked if they have noticed any problem with their hearing. The clinician then speaks in a whisper (counting in numbers) at arm’s length from the patient, while occluding the nontested ear with the hand and notes if hearing loss is reported or demonstrated.

Weber’s test involves striking a 256 or 512 Hz tuning fork on the examiner’s knee and placing it on the patient’s forehead. Normally this should be heard in the middle of the head and should not lateralize. When the sound does lateralize, it does so to the side of greater conductive loss or that with the intact cochlea (to the opposite side) in sensori-neural hearing loss.

The Rinne test again utilizes the vibrating tuning fork. The tuning fork is applied firmly to the mastoid process behind the ear and is then held in front of the external auditory meatus. The patient is asked which they hear loudest. Patients with normal middle ear function hear well by air rather than by bone conduction. Those with conductive deafness

experience the reverse. The external auditory meatus and tympanic membrane are examined with the auroscope. Conductive deafness is common (wax, middle ear disease). Sensori-neural deafness is less common and takes three forms:

Cochlea, e.g. noise, Ménière’s disease.

Nerve lesion, e.g. meningitis, acoustic neuroma.

Brainstem, e.g. vascular, demyelinating disease.

Examination of the vestibular nerve includes testing gait, nystagmus, and caloric testing (see Chapter 2).

CRANIAL NERVE IX (GLOSSOPHARYNGEAL NERVE)

Sensation on the posterior wall of the tonsillar fossa is examined with an orange stick. The motor

(stylopharyngeus) and autonomic (parotid glands) components are not tested.

CRANIAL NERVE X (VAGUS NERVE)

Articulation, cough, and ability to elevate the soft palate (‘saying Ah!’) are tested. Touching the posterior pharyngeal wall on each side with a throat swab and comparing each response tests the gag reflex. The autonomic and sensory (external auditory meatus/external ear) are not tested at the bedside.

CRANIAL NERVE XI (ACCESSORY NERVE)

The sternocleidomastoid muscle is tested by tilting the head to the opposite side while applying resistance against the examiner’s hand, pressing on the angle of the jaw. The muscle belly can be observed to stand out. Asking the patient to shrug the shoulders against resistance also tests the trapezius muscle.

CRANIAL NERVE XII (HYPOGLOSSAL NERVE)

The tongue at rest on the floor of the mouth is examined for wasting and fibrillation. The patient is asked to protrude the tongue and any deviation noted. The tongue should also be observed for reduced movement as seen in UMN lesions.

Multiple cranial nerve palsies

Patterns of multiple cranial nerve palsies due to extraaxial lesions reflect their anatomical relationships (Table 3).

MOTOR EXAMINATION

Evaluation of patterns of limb weakness is essential for localizing disease. Weakness may affect a single limb (monoplegia), arm and leg on the same side (hemiplegia), or all limbs (tetraplegia). Weakness may be proximal (muscle disease or inflammatory neuropathy) or distal (axonal neuropathy). Observations on muscle wasting, abnormal movements, tone, and reflex state help to differentiate UMN from LMN disorders. Finally, weakness that does not follow a recognizable organic pattern may be psychologically based. The components of assessment are:

OBSERVATION

Involuntary movements, e.g. extrapyramidal disease, fasciculation, myokymia.

Muscle symmetry.

Left to right (mononeuropathy, e.g. carpal tunnel).

Proximal versus distal, e.g. myopathy or neuropathy.

EXAMINATION OF MUSCLE TONE

The patient is asked to relax and the upper and lower limbs are tested. The patient’s fingers, wrist, and elbow are flexed and extended. Similarly, the patient’s ankle and knee are flexed and extended. Normally, a small, continuous resistance to passive movement is felt, and decreased (flaccid) or increased (rigid/spastic) tone should be noted. Failure to relax is a common problem. A flaccid (weak) limb suggests a LMN disorder, while a spastic (weak) limb suggests UMN problems. Rigidity occurs in extrapyramidal disease and fluctuating stiffness (paratonia or Gegenhalten) with diffuse frontal lobe disturbance.

EXAMINATION OF MUSCLE STRENGTH

Muscle strength is under corticospinal (UMN) and anterior horn cell/nerve root/nerve plexus/peripheral nerve/neuromuscular junction (LMN) control. The target of all pathways is the muscle itself. Muscle strength is tested by having the patient move against the examiner’s resistance. One side is always compared with the other and strength is graded on a scale from 0–5/5 (Table 4).

When testing, the following should be considered: the overall distribution (proximal versus distal), the pattern (flexor versus extensor), and the grouping (single root versus multiple roots versus plexus versus single nerve versus multiple nerves). There is no avoiding knowing the detailed innervation of muscles. In a minimal examination the following should be tested:

Table 4 Grading of motor strength

Upper limbs

Flexion at the elbow (C5, C6, biceps).

Extension at the elbow (C6, C7, C8, triceps).

Extension at the wrist (C6, C7, C8, radial nerve).

Finger abduction (C8, T1, ulnar nerve).

Opposition of the thumb (C8, T1, median nerve).

Lower limbs

Flexion at the hip (L2, L3, L4, iliopsoas).

Adduction at the hips (L2, L3, L4, adductors).

Abduction at the hips (L4, L5, S1, gluteus medius and minimus).

Extension at the hips (S1, gluteus maximus).

Extension at the knee (L2, L3, L4, quadriceps).

Flexion at the knee (L4, L5, S1, S2, hamstrings).

Dorsiflexion at the ankle (L4, L5).

Plantar flexion (S1).

Pronator drift

The patient is asked to stand for 20–30 seconds with both arms straight forward, palms up, and eyes closed, keeping the arms still while the examiner gently taps downwards. In pronator drift, the patient fails to maintain extension and supination (and the limb ‘drifts’ into pronation). Pronator drift is seen in UMN disease.

REFLEXES

The tendon reflex comprises a stretch sensitive afferent (from muscle spindles) via a single synapse (anterior horn cell region) to the efferent (motor) nerve. These reflexes are accentuated in UMN disease and diminished or absent with LMN disorders.

Deep tendon reflex

Patients must be relaxed and positioned properly before starting the test. No more force with the tendon hammer should be used than is required to provoke a definite response. Reflexes can be ‘reinforced’ by asking the patient to perform isometric contraction of other muscles groups (clenched teeth, upper limbs or pull on hands, lower limbs). Reflexes should be graded on a 0 to 4 ‘plus’ scale (Table 5).

The following reflexes should be tested:

Biceps (C5, C6): examiner’s thumb or finger is placed firmly on the biceps tendon and the examiner’s fingers are struck with the reflex hammer.

Triceps (C6, C7): the patient’s upper arm is supported and the patient’s forearm is allowed to hang free; the triceps tendon is struck above the elbow.

Brachioradialis (C5, C6): the patient’s forearm rests on their abdomen or lap and the radius is struck about 3–5 cm (1–2 inches) above the wrist.

Abdominal (T8, T9, T10, T11, T12): a blunt object is used to stroke the patient’s abdomen lightly on each side in an inward and downward direction above (T8, T9, T10) and below the umbilicus (T10, T11, T12), while noting contraction of the abdominal muscles with deviation of the umbilicus towards the stimulus.

Knee (L2, L3, L4): the patient sits or lies down with the knee flexed and the patellar tendon is struck just below the knee.

Ankle (L5 S1): the patient’s foot is dorsiflexed at the ankle and the Achilles tendon struck.

CLONUS

If the reflexes are hyperactive, clonus is tested for. This can be done at any joint but is usually performed at the ankle. The knee is supported in a partly flexed position and the foot then quickly dorsiflexed. Clonus is manifest by rhythmic sustained oscillations.

PLANTAR RESPONSE (BABINSKI)

A positive Babinski sign indicates UMN disease while a negative test is normal. The lateral aspect of the sole of each foot is stroked with the end of a reflex hammer and movement of the toes noted. The normal movement is that of plantar flexion. Extension of the big toe with fanning of the other toes is abnormal, a positive Babinski.

Table 5 Tendon reflex grading scale