Visual acuity Assessment of visual acuity (distance)īegin by assessing the patient’s visual acuity using a Snellen chart. This procedure should be undertaken only after approved training, supervised practice and competency assessment, and carried out in accordance with local policies and protocols.You might also be interested in our OSCE Flashcard Collection which contains over 2000 flashcards that cover clinical examination, procedures, communication skills and data interpretation. If necessary, inform the nurse in charge of any changes or abnormalities.Document the findings of the pupillary assessment as per local policy and guidelines (Fig 6).Repeat the above procedure in the opposite eye.Taking care to avoid shining the light in the other eye, observe whether the opposite pupil also reacts (consensual reflex).After providing prior warning to the patient, move the torchlight from the side of the head towards the pupil (Fig 5) and note any change in pupil size and the speed of the reaction (brisk or sluggish).Note the size (mm) of each pupil if available use the scale printed on the neurological assessment chart as a comparison (Fig 4).Look into each of the patient’s eyes, examining the size of the pupils (Fig 3).Adopt a position in front of the patient.If possible, dim the overhead light source (Fig 2) (a darkened room is ideal but practically this will rarely be possible) dim light will facilitate a better view of the pupils and their reaction to light.Assemble equipment: a pen torch and the patient’s observation chart (in some situations a neurological assessment chart).Undertake pre-procedure checks (see above) to ascertain if there are any pre-existing irregularities with the patient’s eyes or factors that can influence pupillary assessment findings.Explain the procedure to the patient, even if she or he is unconscious (Fig 1).Check if there are any pre-existing factors that can cause pupillary constriction, for example medications including narcotics and topical beta-blockers.Check if there are any pre-existing factors that can cause pupillary dilation, for example medications including tricyclics, atropine and sympathomimetics and traumatic mydriasis (Bersten et al, 2003).Note if the patient has any pre-existing irregularity with the pupils, for example cataracts, false eye or previous eye injury.Prior to undertaking pupillary assessment: Unreactive pupils can be caused by an expanding mass, for example a blood clot exerting pressure on the third cranial nerve a fixed and dilated pupil may be due to herniation of the medial temporal lobe. Both pupils should react equally to light. Pupil reaction should be documented as per local policy, for example B (brisk), S (sluggish) or N (no reaction). There should also be a consensual reaction to the light source, that is the opposite pupil also constricts when the light source is applied to one eye (Jevon, 2007). Pupil reaction to light should be brisk and after removal of the light source, the pupil should return to its original size. It should be round abnormal shapes may indicate cerebral damage oval shape could indicate intracranial hypertension (Fairley, 2005). The average size is 2-5mm (Bersten et al, 2003). Pupil size should be measured, ideally with reference to a neurological observation chart or similar. Compression of this nerve will result in fixed dilated pupils (Fairley, 2005).Īny changes in the patient’s pupil reaction, size or shape, together with other neurological signs, are an indication of raised intracranial pressure (ICP) and compression of the optic nerve. Evaluation of pupillary reaction is effectively an assessment of the third cranial nerve (oculomotor nerve), which controls constriction of the pupil.

Pupil chart