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CLINICAL GUIDELINE
Pupil Dilation
Note: The following document provides information about pupil dilation for ocular examination in
optometric practice. It should not be used as a substitute for statutory responsibilities and
optometrists must ensure that they comply with State and Federal Laws. These guidelines do not
advise on therapeutic use of mydriatics utilised in the management for iritis, amblyopia or surgery.
Summary
• Optometrists regularly perform pupil dilation to comprehensively examine the ocular fundus as part
of a comprehensive eye health examination where clinically indicated.
• Tropicamide (0.5% - 1.0%) is a safe pupil dilating agent for use in primary care. Tropicamide may
be augmented with phenylephrine 2.5% if maximal dilation required.
• Optometrists should familiarise themselves with the requirements of record keeping and patient
pupil dilation. In particular, should a patient decline pupil dilation, records should reflect that the
patient was advised that this may result in (ocular or other) pathology going undetected.
• Optometrists should discuss pupil dilation with patients, and appropriately document discussions
and procedures in patient records accordingly. Patients should be warned of potential side effects
of pupil dilation. These include the possibility of precipitating angle closure glaucoma, though rare,
and the resultant visual blur. Driving immediately afterwards should be actively discouraged and
where possible patients should be warned of this at the time of booking their appointment.
• Legal precedents overseas have recognised the lower risk of iatrogenic disease precipitated by
pupil dilation versus the possibility that pathology may be missed. When performing pupil dilation,
this and other considerations should inform consulting room procedures and record keeping.
• Reversal of pupil dilation is not recommended as a standard procedure following pupil dilation as
this poses risks to the eye, such as secondary angle closure, that outweigh any benefit gained.
Pupil dilation
Optometrists are educated and trained to detect eye disease, if it is present, in patients they examine.
A mydriatic ocular examination may be necessary to detect some eye diseases as it allows better
visualisation of all structures posterior to the pupil and is necessary for examination of the peripheral
ocular fundus. It is also necessary for examination techniques such as binocular indirect
ophthalmoscopy and scleral indentation, and enhances retinal and vitreous examination with precorneal lenses such as the 78 and 90 dioptre lenses, fundus contact lenses and with direct and
monocular indirect ophthalmoscopy. A dilated pupil also enhances the image quality of any diagnostic
imaging performed.
The fear of precipitating angle closure glaucoma should not affect the decision to dilate to perform
fundoscopy. In the context of diabetic retinopathy (DR) management, the National Health and Medical
Research Council (NHMRC) states: “Pupil dilation using 0.5 to 1.0% tropicamide is safe....Two large
OPTOMETRISTS ASSOCIATION AUSTRALIA ABN 17 004 622 431
204 DRUMMOND STREET CARLTON VICTORIA PO BOX 185 CARLTON SOUTH VICTORIA 3053
TELEPHONE 03 9668 8500 FACSIMILE 03 9663 7478 EMAIL oaanat@optometris ts.as n.au
www.optometrists.asn.au
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Australian population studies (MVIP and BMES ) showed high levels of patient acceptance for pupil
1, 2, 3
dilation. These and other population studies have also confirmed the safety of pupil dilation.”
In all cases the optometrist will need to consider indications and risk factors in their decision to perform
a dilated ocular fundus examination. Legal issues such as negligence (failure to dilate when
indicated) and informed consent need to be considered.
Indications for pupil dilation
There are many clinical indications for pupil dilation and some of these are listed in Table 1 though this
is not an exhaustive list.
There is no definitive list of patients that must have their pupils dilated. Signs and symptoms that may
be indications for a dilated pupil examination are outlined in Table 1.
Table 1. Common indications for pupil dilation
Conditions
Diabetes3
Uveitis
Pigmented fundus lesion
Suspected or diagnosed glaucoma
Lattice degeneration and other peripheral retinal lesions
Penetrating trauma
Recent blunt trauma
Cataract
Hypertension
MD
High myopia
History of metastatic cancer
Symptoms
Flashes and floaters
New distortion
Unexplained reduction in/loss of vision or visual field
Recent blunt force trauma
Other
Relevant family ocular history
Small pupils, nystagmus or unsteady fixation
Where stereoscopic viewing is essential
Systemic medications with potential ocular side effects
To obtain good imaging results
1
Melbourne Visual Impairment Project
2
Blue Mountains Eye Study
3
NHMRC Guidelines for Management of Diabetic Retinopathy report dilation using 0.5% to 1.0% tropicamide is safe
CLINICAL GUIDELINE Pupil Dilation
Adopted November 2005, Reviewed April 2013
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Contraindications to, and risk factors for, pupil dilation
Although optometrists should be aware of the potential to induce acute angle closure glaucoma from
use of mydriatic drops, its incidence is rare and NHMRC Diabetic Retinopathy Guidelines state that
tropicamide alone has not been reported to cause this. Concerns about the possibility of precipitating
an angle-closure glaucoma attack must be weighed against the importance of detecting ocular
pathology.
Despite the small risk of precipitating acute angle-closure glaucoma with tropicamide, patients should
be screened for narrow anterior chamber angles. The Van Herick technique provides reasonable
estimates of anterior chamber angles. Where Van Herick assessment is suggestive of risk, the angle
should be first assessed with gonioscopy prior to pupil dilation.
Tonometry should be performed both prior to and after dilation; a small (3mmHg) intraocular pressure
rise may occur after dilation. If a practitioner feels uncertain about a subsequent intraocular pressure
increase, or if the intraocular pressure is unusually high following pupil dilation, ophthalmologic advice
should be sought.
Particular clinical presentations are nonetheless considered contraindications for pupil dilation and
these are listed below:
• Iris fixated IOLs (absolute contraindication)
• Narrow anterior chamber angles or known or suspected predisposition to angle closure glaucoma
• Active corneal disease or corneal epithelial erosion
• Subluxated posterior chamber IOLs or crystalline lens
• Hyphaema
• When pupil reactions need to be preserved, such as when same day referral is required in iris or
head trauma or neurological anomalies
• Patients under miotic therapy for angle closure glaucoma
• Suspected penetrating ocular injury
• Known hypersensitivity to mydriatic drug
Pregnant and nursing women
Optometrists should exercise caution in dilating pupils in pregnant and breast feeding mothers. In
particular this should be avoided in the first trimester. If pupils must be dilated, tropicamide is
recommended.
Proceeding with pupil dilation
Once an optometrist has made a decision to recommend pupil dilation to a patient, the importance of
pupil dilation should be discussed with the patient. They should be made aware that their vision will
be blurred for up to 4-6 hours afterwards. It should be emphasised that they should not drive or
operate heavy machinery in this time if their visual acuity is reduced. Where possible this conversation
should occur prior to the appointment whether with the optometrist or their support staff. This
discussion should be noted in the patient record card.
Patient permission must be obtained for pupil dilation following explanation of possible side-effects
and risk factors. Optometrists are encouraged to inform patients of the small risk of inducing acute
CLINICAL GUIDELINE Pupil Dilation
Adopted November 2005, Reviewed April 2013
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angle-closure glaucoma (about one in 5,000). It may be beneficial to develop a ‘script’ which covers
potential side effects and risks in a simple way when obtaining patient consent.
Record keeping
It is advised that the following details be documented on a patient’s clinical record:
• Visual acuity prior to instillation of dilating agent/s
• That informed consent was received prior to instillation of dilating agent/s including a discussion of
risks and possible side-effects (advice against driving immediately after dilation owing to visual
blur/disturbance)
• Time of instillation as well as the dilating agent/s and strength used
• Information on patient general health including (known) current medicines (so as to minimise risk of
drug-interactions by highlighting any contraindications to dilation)
• Any patient refusal to have their pupils dilated despite optometrist recommendation including the
risk to the patient that pathology may go undetected without dilation
• Gonioscopy observations (where performed)
• Pre- and post- dilation tonometry measurements
Preferred mydriatic drugs
The following list provides key points about the more commonly used dilating agents (mydriatic drugs)
in optometric practice. The Australian Therapeutic Goods Administration (TGA) provides product and
consumer information on the following drugs that can be viewed online:
https://www.ebs.tga.gov.au/ebs/picmi/picmirepository.nsf/PICMI?OpenForm&t=&k=C&r=/
Tropicamide 0.5% and 1%
• Tropicamide is an anti-muscarinic drug that blocks the responses of the sphincter muscle of the iris
and the accommodative muscle of the ciliary body (mildly) to cholinergic stimulation, producing
mydriasis within 20-40 minutes of instillation and (weak) cycloplegia maximal within 30 minutes.
Both effects usually last up to 6 hours.
• 0.5% produces slightly less dilation than 1% however 1% produces greater cycloplegia.
• The mechanism of action minimises the risk of pupil block.
• Hypersensitivity (allergic) to tropicamide may be displayed by some patients.
• Should be used with caution in patients with conditions characterised by tachycardia as it may
accelerate heart rate.
• As with other mydriatic-cycloplegics, tropicamide can raise intraocular pressure in eyes with openangle glaucoma. This effect is thought to be caused by a decrease in the outflow facility. This
pressure elevation is usually less than 5 mmHg and can be considered insignificant in most
patients, since it will subside in several hours.
• Dilation of narrow angles is generally considered to be safer with anti-muscarinic drugs such as
tropicamide. Adrenergic drugs such as phenylephrine, because of their mode of action, increase
the risk of pupil block.
CLINICAL GUIDELINE Pupil Dilation
Adopted November 2005, Reviewed April 2013
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• Because tropicamide is devoid of vasopressor effects, it is the safest mydriatic agent for use in
patients with systemic hypertension, angina, or other cardiovascular disease
Phenylephrine (Phenylephrine hydrochloride) 2.5% and 10%
• Phenylephrine is a direct acting sympathomimetic agent. It causes mydriasis by affecting the iris
dilator muscle. Maximal mydriasis occurs in 10-90 minutes with recovery after 5-7 hours. There is
almost no cycloplegic effect
• 10% is contraindicated in children and the elderly because of the risk of systemic toxicity.
Hypersensitivity (e.g. allergic contact blepharoconjunctivitis) is rare but may be displayed by some
patients
• In most cases there is no significant difference on pupil dilation between the 2.5% and 10%
concentrations
• Phenylephrine should be used with caution in the following patient groups:
• those with cardiac disease, hypertension, aneurysms, long-standing insulin dependent
diabetes mellitus and tachycardia
• patients on monoamine oxidase inhibitors, tricyclic antidepressants and antihypertensive
agents (including beta blockers)
• patients with closed angle glaucoma (unless previously treated with iridectomy)
• patients with a narrow angle prone to glaucoma precipitated by mydriatics
• Phenylephrine will also contract the smooth muscle of the arterioles of the conjunctiva and eyelids,
causing blanching of the conjunctiva and possible lid retraction
Cyclopentolate
• Cyclopentolate hydrochloride is an antimuscarinic compound which produces mydriasis and
cycloplegia
• Maximum effects produced within 30-60 minutes and accommodation recovers within 24 hours
although in some individuals complete recovery may take several days
• Premature and small infants are especially prone to central nervous system (CNS) and
cardiopulmonary side effects from systemic absorption of cyclopentolate and cyclopentolate is
contraindicated in these patients
• The elderly and children with spastic paralysis or brain damage are also more susceptible to CNS
effects of cyclopentolate
• Cyclopentolate recommended dosage is included in the Appendix
Practical tips/hints
The following practical tips may be considered to enhance the clinical effectiveness of pupil dilation.
• Prior instillation of a topical anaesthetic increases the speed of onset of both tropicamide and
phenylephrine by reducing irritation caused by the medication and enhancing corneal permeability.
It also prolongs the recovery time.
CLINICAL GUIDELINE Pupil Dilation
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• Dilation of narrow angles is generally considered to be safer with anticholinergic drugs such as
tropicamide. Adrenergic drugs such as phenylephrine 2.5%, because of their mode of action,
increase the risk of pupil block.
• Instillation of one drop of 2.5% phenylephrine followed (5 minutes later) by one drop of tropicamide
0.5% or 1.0% is likely to give a greater dilation than either drug used alone – maximising effect on
both the iris sphincter muscle and the iris dilator muscle. This can be useful for patients whose
pupils are difficult to dilate including patients with diabetes. Consideration should be given to
presence of significant cardiovascular disease which would contraindicate use of phenylephrine.
• Angle-closure glaucoma precipitated through dilation with tropicamide is most likely to occur within
an hour of initial instillation. If intraocular pressure has not risen significantly in the first hour, the
probability of angle closure occurring is extremely low, the patient may be warned of symptoms of
an acute angle closure attack and allowed to leave the practice following the procedure with
instructions of what actions to take if symptoms occur (ocular pain, nausea, red eye, reduced
vision).
• It is not recommended that optometrists attempt to reverse pupillary dilation with pilocarpine owing
to the increased risks of angle closure glaucoma, headaches, or retinal tears in high myopes.
The Optometry Board of Australia (OBA) Scheduled Medicines Advisory Committee (SMAC)
guidelines include a pathway for the management of acute angle closure glaucoma and these can be
viewed on the OBA website http://www.optometryboard.gov.au/Policies-Codes-Guidelines.aspx
CLINICAL GUIDELINE Pupil Dilation
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Appendix
Recommended drug regimens for routine dilation of pupils
Simple eyelid closure AND digital occlusion of the tear duct for at least two minutes after eye drop
instillation reduces systemic absorption of any topical drug by up to two-thirds. Thereby, the safety
margin of any instilled medication can be expanded significantly.4
In systemic disease and with concomitant drug therapies tropicamide 0.5%-1% remains the mydriatic
of choice as phenylephrine is frequently contraindicated.
Clinical situation (patient)
Dosage / regimen – what can be used and how
Tropicamide 0.5% and 1.0% 1-2 drops in both eyes (OU)
Adults
Phenylephrine 2.5% one drop OU
(> 12 years)
Cyclopentolate 1 drop of 0.5% or 1% OU
Tropicamide 0.5%-1% 1-2 drops OU
Cyclopentolate 3 months-12 years 1 drop of 0.5% solution OU
Children
Cyclopentolate >12 years 1 drop of 0.5% or 1% OU
Phenylephrine 2.5% - not 10% - one drop OU
Cyclopentolate <3 months not recommended
Cyclopentolate over 3 months of age 1 drop of 0.5% solution
Neonates (newborns) & infants
Tropicamide 0.5%-1.0% 1 drop OU
Phenylephrine 2.5% 1 drop OU
Exercise caution and avoid dilating in the first trimester.
Pregnancy/breast feeding mothers
If essential, tropicamide is recommended.
4
Goldberg I. Drugs for glaucoma. Aust Prescr 2002;25:142-6
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References
1. National Health and Medical Research Council, Guidelines for the management of diabetic
retinopathy, 2008 Accessed via:
http://www.nhmrc.gov.au/_files_nhmrc/publications/attachments/di15.pdf
2. McCarty,DJ, Fu,CL, Harper,CA, Taylor,HR, McCarty,CA. Five-year incidence of diabetic
retinopathy in the Melbourne Visual Impairment Project. Clin Exp Oph 2003;31:397-402.
3. Cikamatana L, Mitchell P, Rochtchina E, Foran S, Wang JJ. Five-year incidence and progression
of diabetic retinopathy in a defined older population: the Blue Mountains Eye Study. Eye.
2007;21:465-471
4. Liew G, Mitchell P, Wang JJ, Wong TY. Fundoscopy: to dilate or not to dilate? BMJ 2006;332: 3.
(7 January.)
5. Bhan KJ et al. Funduscopy: to dilate or not? Precipitation of angle closure may not be a disservice
BMJ. 2006 January 21; 332(7534): 179.
6. Siderov J, Bartlett JR, Madigan CJ. Pupillary dilation: the patient’s perspective. Clin Exp Optom
1996; 79: 62-66
7. Inan UU, Ozturk F, Ermis SS. Pharmacologic pupil dilation in diabetic patients. Retina
2003;23:254-256
8. Lachkar Y, Bouassida W, Drug-induced acute angle closure glaucoma Curr Opin Ophthalmol
2007 Mar;18(2):129-33
9. Johnson, M. Ophthalmic drugs Part 4 — Mydriatic drugs: practical considerations. Optician 31-082012
10. Johnson, M. Ophthalmic drugs Part 3 — Mydriatic drugs – which ones to use when and how they
work Optician 24-08-2012
11. Class JG. A review of 50 malpractice claims. J Am Optom Assoc, 1989;60:694-706
12. Palmboom GG, et al. Doctor’s views on disclosing or withholding information on low risks of
complication. J Med Ethics 2007; 33:67-70.
13. Motta M.M.S, Coblentz J, Fernandes B.F, Burnier, Jr. M.N,
Mydriatic and Cardiovascular Effects of Phenylephrine 2.5% versus Phenylephrine 10%, Both
Associated with Tropicamide 1% Ophthalmic Res 2009;42:87–89
14. Rosenfeld M, Logan N, Edwards K. Optometry: Science, Techniques and Clinical Management.
nd
2 edition. Elsevier Ltd 2009
15. Product Information: Tropicamide
https://www.ebs.tga.gov.au/ebs/picmi/picmirepository.nsf/pdf?OpenAgent&id=CP-2010-PI-06731-3
16. Product Information: Phenylephrine
https://www.ebs.tga.gov.au/ebs/picmi/picmirepository.nsf/pdf?OpenAgent&id=CP-2010-PI-06685-3
17. Fricke TR, Mantzioros N, Vingrys AJ. Management of patients with narrow angles and acute
angle-closure glaucoma Clin Exp Optom 1998; 81: 6: 255–266
18. Bartlett JD, Jaanus SD eds. Clinical Ocular Pharmacology, 4th edition. Boston, Mass: ButterworthHeinemann, 2001
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19. Pandit RJ, Taylor R. Mydriasis and glaucoma: exploding the myth. A systematic review. Diabet
Med. 2000; 17: 693-9
20. Product Information: Cyclopentolate eye drops
https://www.ebs.tga.gov.au/ebs/picmi/picmirepository.nsf/pdf?OpenAgent&id=CP-2010-PI-066403
21. Gilmartin, B., Amer, A. C. and Ingleby, S. (1995), Reversal of tropicamide mydriasis with single
instillations of pilocarpine can induce substantial pseudo-myopia in young adults. Ophthalmic and
Physiological Optics, 15: 475–479. doi: 10.1046/j.1475-1313.1995.9500076p.x
22. Botelho C, Rodrigues J, Castel Branco M.G. Allergic contact blepheroconjunctivitis with
phenylephrine eyedrops –the relevance of late readings of intradermal tests Allergologia et
Immunopathologia Volume 35, Issue 4, July 2007, Pages 157–158
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