GENERAL APPROACH TO HISTORY AND EXAMINATION

Published on 12/04/2015 by admin

Filed under Neurology

Last modified 12/04/2015

Print this page

This article have been viewed 2925 times

SECTION I GENERAL APPROACH TO HISTORY AND EXAMINATION

NERVOUS SYSTEM – HISTORY

An accurate description of the patient’s neurological symptoms is an important aid in establishing the diagnosis; but this must be taken in conjunction with information from other systems, previous medical history, family and social history and current medication. Often the patient’s history requires confirmation from a relative or friend.

The following outline indicates the relevant information to obtain for each symptom, although some may require further clarification.

NERVOUS SYSTEM – EXAMINATION

Neurological disease may produce systemic signs and systemic disease may affect the nervous system. A complete general examination must therefore accompany that of the central nervous system. In particular, note the following

CNS examination is described systematically from the head downwards and includes:

EXAMINATION – CONSCIOUS LEVEL ASSESSMENT

A wide variety of systemic and intracranial problems produce depression of conscious level. Accurate assessment and recording are essential to determine deterioration or improvement in a patient’s condition. In 1974 Teasdale and Jennett, in Glasgow, developed a system for conscious level assessment. They discarded vague terms such as stupor, semicoma and deep coma, and described conscious level in terms of EYE opening, VERBAL response and MOTOR response.

The Glasgow coma scale is now used widely throughout the world. Results are reproducible irrespective of the status of the observer and can be carried out just as reliably by paramedics as by clinicians

EYE OPENING – 4 categories

MOTOR RESPONSE – 5 categories

Obeys commands

Localising to pain

Apply a painful stimulus to the supraorbital nerve, e.g. rub thumb nail in the supraorbital groove, increasing pressure until a response is obtained. If the patient responds by bringing the hand up beyond the chin = ‘localising to pain’. (Pressure to nail beds or sternum at this stage may not differentiate ‘localising’ from ‘flexing’.)

Flexing to pain

If the patient does not localise to supraorbital pressure, apply pressure with a pen or hard object to the nail bed. Record elbow flexion as ‘flexing to pain’. Spastic wrist flexion may or may not accompany this response.

Extending to pain

If in response to the same stimulus elbow extension occurs, record as ‘extending to pain’. This is always accompanied by spastic flexion of the wrist.

None

Before recording a patient at this level, ensure that the painful stimulus is adequate.

During examination the motor response may vary. Supraorbital pain may produce an extension response, whereas fingernail pressure produces flexion. Alternatively one arm may localise to pain; the other may flex. When this occurs record the best response during the period of examination (this correlates best with final outcome). For the purpose of conscious level assessment use only the arm response. Leg response to pain gives less consistent results, often producing movements arising from spinal rather than cerebral origin.

EXAMINATION – HIGHER CEREBRAL FUNCTION

COGNITIVE SKILL

Dominant hemisphere disorders

Listen to language pattern

Expressive dysphasia

Receptive dysphasia Does the patient understand simple/complex spoken commands?
e.g. ‘Hold up both arms, touch the right ear with the left fifth finger.’ Receptive dysphasia Ask the patient to name objects. Nominal dysphasia Does the patient read correctly? Dyslexia Does the patient write correctly? Dysgraphia Ask the patient to perform a numerical calculation, e.g. serial 7 test, where 7 is subtracted serially from 100. Dyscalculia Can the patient recognise objects? e.g. ask patient to select an object from a group. Agnosia

Non-dominant hemisphere disorders

Note patient’s ability to find his way around the ward or his home.	Geographical agnosia
Can the patient dress himself?	Dressing apraxia
Note the patient’s ability to copy a geometric pattern, e.g. ask patient to form a star with matches or copy a drawing of a cube.	Constructional apraxia

Mini Mental Status Examination (MMSE) is used in the assessment of DEMENTIA (page 127).

MEMORY TEST

Testing requires alertness and is not possible in a confused or dysphasic patient.

REASONING AND PROBLEM SOLVING

Test patient with two-step calculations, e.g. ‘I wish to buy 12 articles at 7 pence each. How much change will I receive from £1?’

Ask patient to reverse 3 or 4 random numbers.

Ask patient to explain proverbs.

Ask patient to sort playing cards into suits.

The examiner must compare patient’s present reasoning ability with expected abilities based on job history and/or school work.

EMOTIONAL STATE

Anxiety or excitement

Depression or apathy

Emotional behaviour

Uninhibited behaviour

Slowness of movement or responses

Personality type or change.

CRANIAL NERVE EXAMINATION

OLFACTORY NERVE (I)

Test both perception and identification using aromatic non-irritant materials that avoid stimulation of trigeminal nerve fibres in the nasal mucosa, e.g. soap, tobacco.

One nostril is closed while the patient sniffs with the other.

OPTIC NERVE (II)

N.B. Refractive error (i.e. inadequate focussing on the retina, e.g. hyper-metropia, myopia) can be overcome by testing reading acuity through a pinhole. This concentrates a thin beam of vision on the macula.

Visual fields

Gross testing by CONFRONTATION. Compare the patient’s fields of vision by advancing a moving finger or, more accurately, a red 5 mm pin from the extreme periphery towards the fixation point. This maps out ‘cone’ vision. A 2 mm pin will define central field defects which may only manifest as a loss of colour perception.

In the temporal portion of the visual field the physiological blind spot may be detected. A 2 mm object should disappear here.

The patient must fixate on the examiner’s pupil.

Peripheral visual fields are more sensitive to a moving target and are tested with a GOLDMANN PERIMETER.

The patient fixes on a central point. A point of light is moved centrally from the extreme periphery. The position at which the patient observes the target is marked on a chart. Repeated testing from multiple directions provides an accurate record of visual fields.

Central fields are charted with either a Goldmann perimeter using a small light source of lesser intensity or a TANGENT (BJERRUM) SCREEN. The HUMPHREY FIELD ANALYSER provides an alternative and particularly sensitive method of testing central fields. This records the threshold at which the patient observes a static light source of increasing intensity.

Optic fundus (Ophthalmoscopy)

Ask the patient to fixate on a distant object away from any bright light. Use the right eye to examine the patient’s right eye and the left eye to examine the patient’s left eye.

If small pupil size prevents fundal examination, then dilate pupil with a quick acting mydriatic (homatropine). This is contraindicated if either an acute expanding lesion or glaucoma is suspected.

Pupils

Size (small = miosis/large = mydriasis)

Reaction to light: both pupils constrict when light is shone in either eye

Reaction to accommodation and convergence: pupil constriction occurs when gaze is transferred to a near point object.

OCULOMOTOR (III), TROCHLEAR (IV) AND ABDUCENS (VI) NERVES

A lesion of the III nerve produces impairment of eye and lid movement as well as disturbance of pupillary response.

Pupil: The pupil dilates and becomes ‘fixed’ to light.

Ptosis: Ptosis is present if the eyelid droops over the pupil when the eyes are fully open. Since the levator palpebrae muscle contains both skeletal and smooth muscle, ptosis signifies either a III nerve palsy or a sympathetic lesion and is more prominent with the former.

Ocular movement

Steady the patient’s head and ask him to follow an object held at arm’s length. Observe the full range of horizontal and vertical eye movements.

Note any malalignment or limitation of range.

Examine eye movements in the six different directions of gaze representing maximal individual muscle strength.

Question patient about diplopia; the patient is more likely to notice this before the examiner can detect impairment of eye movement. If present:

– note the direction of maximum displacement

Buy Membership for Neurology Category to continue reading. Learn more here

Related

Neurology and Neurosurgery Illustrated