Refraction (5 cr)

Objective

Knowledge base
Students are able to
• describe the principle of the test for refraction
• describe mechanism of presbyopia and facts affecting that
• calculate the range of accommodation in presbyopia and introduce lenses for different distances
• describe the eye movements and normal functions
• describe the features of anisometropia

Clinical/practical base
Students are able to
• do the procedure of subjective monocular refraction also in case of high ametropia using cross cylinder, astigmatic dials, fogging methods, and duochrome methods
• do the procedure of subjective binocular refraction using accommodation equalisation techniques
• use phoropter and automated phoropter
• use autorefractometer and implement the results
• recognize the presbyopic symptoms and determine near addition
• measure convergence near point and exam the saccades and pursuit movements
• do the procedure of H-test and cover test
• record the measurement values with understandable and agreedable notation

Content

Subjective tests:
o cross cylinder
o asticmatic dial
o fogging methods
o duochrome methods
o equalisation techniques: polarized test, bichrome balance test, fogging balance test
Extra ocular muscles and eye movements:
o eye movements and control mechanism
o eye movements and dynamics and kinematics
o agonist-antagonist relationship
o first, secondary and tertiary effects
o muscle actions in different viewing directions
o H-test and cover test
o reflex movements and compensation movements
o micro saccades and steady fixation
o fixation
o versio movements - pursuits and saccades
-measurement, NSUCO-methods
o vergence - tonic, accommodative, fusional and proximal
o convergence near point and measuring it
Presbyopia
o definition, epidemiogy, classification, symptoms, mechanism, treatment, correction
o accommodation amblitude measurement: Prince-rule
o define the near addition with accommodation amblitude, dynaamic cross cylinder, trial lenses, NRA/PRA -test
Autorefractometry- principal, use and implementation

Location and time

Teaching is given at Myllypuro campus and via online sessions (Teams)
Spring semester 2025, 2.period, as the given schedule
The practical exercises included in the course are done according to the schedule and in the order given in the training facilities of the campus. Tasks and exercises other than those related to on-the-job training cannot be done under the supervision of working life.

Materials

Lecture notes, articles
Literature among other things:
Primary Care Optometry: Anomalies of Refraction, sivut 3-21, Epideminology of Anetropia/ Myopia / Hyperopia 22-74, The Preliminary examination 112-123, Objective Refraction 183-197 ja 201-207, Subjektive Refraction 209-218 Management of Anomalies of refraction 251-256, Nonsurgical methods of Myopia Control or reduction 370-387
Borish´s Clinical Refraction:
AOA:
Thomson, David. VA testing in optometric practice. Part 1: The Snellen chart. Optometry Today 2005.
Thomson, David. VA testing in optometric practice. Optometry Today 2005. Part 2: Newer chart designs. Optometry Today 2005.
AOA: Care of the patient with Presbyopia
Kukkonen, Kuusela & Tuomaala 2016. Opas näöntutkimuksen objektiivisten testien tekemiseen, tulkintaan ja kirjaamiseen. Opinnäytetyö, Metropolia AMK. Luettavissa: https://issuu.com/kukkonenkuuselatuomaala/docs/opas_versio_18.11._pdf
Ammatillinen ohje optikon toimen harjoittamisesta. Optometrian Eettinen Neuvosto

Teaching methods

Interactive lectures,
Guided practices (15) and assignments
Written individual assignment
Pair and self reflection

Employer connections

No work placement

Exam schedules

Exam: 12.5.2025
Retakes:
1. retake: Exam: 26.-31.5.2025 (excluding 29.5., which is Ascension Day and the campus is closed)
2. retake: Exam: 11.-16.8.2025
More info about Exam: https://oma.metropolia.fi/henkilokunnalle/strategia-ja-kehityspalvelut/digitalisaatio/ohjelmistojen-ohjeet/exam/exam-opiskelijoille

Written assignment in smaller parts during studies, instructions ja tasks will be available in Oma workspace.

Eye exam practicals ready and returned by 13.5.2025. Return practicals (international students) for Johanna Valtanen.

International connections

Exchange students

Completion alternatives

N/A

Student workload

1 ECTS credit is approximately 27h student work, 5 credits = 135 h

If the student has individualized educational support arrangements, shall this student contact the teacher of the course immediately after the end of the registration period (or latest before the start of the course.)

It is not allowed to use or distribute any tasks, assignments or MATERIALS in any other way than in student's own studies. Distributing ONLY with teacher's personal permission.

Further information

The previous course of eye examination must be successfully completed before moving on to the next eye examination course.
Eye movements:
• characteristics and control of the various eye movements, objective test: NPC, cover test, H-test, pursuits and saccades (NSUCO), Duane and Push up-accommodation amplitudi test
Subjective clinical tests: clinical use, instrumentation, procedure, implications
• visual acuity
• standard subjective refraction including astigmatic dial technique, crossed cylinders, fogging methods and equalisation (duochrome) techniques

• Presbyopia: Epidemiology and symptoms, Mechanisms of presbyopia, Effects of ageing on the ciliary muscle and accommodation, Anomalies of Presbyopia, Treatment: Add ja deth of field (far point / near point)
- Examination: dynamic cross cylinder test, Prince rule, trial lenses

Instructions on the use of artificial intelligence during the course are given separately. Students should familiarise themselves with Metropolia's AI guidelines and follow them in their study attainments.

Evaluation scale

0-5

Assessment criteria, satisfactory (1)

he student is able to:
- display learning in core content
- use individual professional concepts correctly
- find information for a specific situation
- distinguish between non-theoretical and theoretical information
- act in individual professional situations as instructed - display learning in his professional field
- show that he has achieved the targets for core competence
- follow safety instructions
- display learning in the ethical principles of his professional field
- operate as a member of a student group

Assessment criteria, good (3)

The student is able to:
- display an understanding of concepts and professional knowledge in the field
- assess and limit the amount of information needed
- operate well in typical professional duties and contexts
- operate in a multicultural environment
- operate safely
- act according to professional ethics
- operate in a student group

Assessment criteria, excellent (5)

The student is able to:
- use concepts and knowledge in his field systematically
- assess and use various information sources
- apply professional information in professional assignments
- work in various duties in a variety of operating environments
- act independently and responsibly in professional contexts
- to take safety issues into consideration in his action
- argue his choices on the basis of professional ethics
- organise the activities of a group of students

Assessment criteria, approved/failed

he student is able to:
- display learning in core content
- use individual professional concepts correctly
- find information for a specific situation
- distinguish between non-theoretical and theoretical information
- act in individual professional situations as instructed - display learning in his professional field
- show that he has achieved the targets for core competence
- follow safety instructions
- display learning in the ethical principles of his professional field
- operate as a member of a student group

Assessment methods and criteria

Maintainence in lectures and eyeexaminationpractise
Written examination represets 60% of the final mark
Written assignment including reflection 40% of the final mark
Practical guided assignments done and evaluated (oraly)

Qualifications

Basics of the Eye Examination

Objective

Knowledge base
Students are able to
• describe the principle of the test for refraction
• describe mechanism of presbyopia and facts affecting that
• calculate the range of accommodation in presbyopia and introduce lenses for different distances
• describe the eye movements and normal functions
• describe the features of anisometropia

Clinical/practical base
Students are able to
• do the procedure of subjective monocular refraction also in case of high ametropia using cross cylinder, astigmatic dials, fogging methods, and duochrome methods
• do the procedure of subjective binocular refraction using accommodation equalisation techniques
• use phoropter and automated phoropter
• use autorefractometer and implement the results
• recognize the presbyopic symptoms and determine near addition
• measure convergence near point and exam the saccades and pursuit movements
• do the procedure of H-test and cover test
• record the measurement values with understandable and agreedable notation

Content

Subjective tests:
o cross cylinder
o asticmatic dial
o fogging methods
o duochrome methods
o equalisation techniques: polarized test, bichrome balance test, fogging balance test
Extra ocular muscles and eye movements:
o eye movements and control mechanism
o eye movements and dynamics and kinematics
o agonist-antagonist relationship
o first, secondary and tertiary effects
o muscle actions in different viewing directions
o H-test and cover test
o reflex movements and compensation movements
o micro saccades and steady fixation
o fixation
o versio movements - pursuits and saccades
-measurement, NSUCO-methods
o vergence - tonic, accommodative, fusional and proximal
o convergence near point and measuring it
Presbyopia
o definition, epidemiogy, classification, symptoms, mechanism, treatment, correction
o accommodation amblitude measurement: Prince-rule
o define the near addition with accommodation amblitude, dynaamic cross cylinder, trial lenses, NRA/PRA -test
Autorefractometry- principal, use and implementation

Qualifications

Basics of the Eye Examination