AMBLYOPIA + REFRACTIVE ADAPTATION + PATCHING + ATROPINE + EMMATROPISATION Flashcards

Question

compliance patching

Answer 1

* Compliance better when starting VA better (refractive adaptation) * Dose rates of 2-6 hours resulted in same final outcome * Regular supervision / contact with orthoptist improves compliance and may shorten treatment phase.

Answer 2

Amblyopia improves with optical correction alone in about one fourth of patients aged 7 to 17 years, although most patients who are initially treated with optical correction alone will require additional treatment for amblyopia. * For patients aged 7 to 12 years, prescribing 2 to 6 hours per day of patching with near visual activities and atropine can improve visual acuity even if the amblyopia has been previously treated. * For patients 13 to 17 years, prescribing patching 2 to 6 hours per day with near visual activities may improve visual acuity when amblyopia has not been previously treated but appears to be of little benefit if amblyopia was previously treated with patching. * PEDIG 2005

Answer 3

* Review every 6-8 weeks after commencement of treatment to monitor improvement and / or adjust the prescribed hours of occlusion. If acuity fails to improve by at least 4 letters each visit the occlusion dose should be increased i.e. from 2 to 4 to 6 hours.

Answer 4

* Paralyses the ciliary muscles to optically defocus the non-amblyopic eye * Effect lasts for longer than other cycloplegics – up to 14 days * Greater effect for near VA than distance * Daily atropine Vs Weekend atropine

Answer 5

Mean VA after 4 months 0.2 logMAR with daily vs weekend (PEDIG 2004) * ≥10 hours occlusion quicker improvement – no significant difference between all treatments at 6 months (PEDIG 2003)

Answer 6

* 2 hours patching (1.8 lines improvement) vs weekend atropine (1.5 lines improvement) – (7 – 12 year olds in this study)- PEDIG 2009

Answer 7

* Non responders – could add optical penalisation although no great improvement in VA found when compared to atropine alone (about ½ line).

Answer 8

* Alone or in conjunction with Atropine o Lenses used to blur VA of better eye *Total penalisation: Use of amblyopic eye for all distances. Add strong convex lens to the better eye * Suggest the choice is based on degree of amblyopia

Answer 9

Mild – moderate amblyopia with no co-op to patching * *VA static with other treatment * *Older children with anisometropic amblyopia – social reasons * *Latent nystagmus component

Answer 10

180 children with moderate amblyopia *Weekend atropine vs weekend atropine + optical penalisation (plano lens) *18 weeks o2.8 lines improvement in atropine + optical penalisation o2.4 lines improvement in atropine alone *More patients in atropine + optical penalisation had reduced sound eye VA – no reports of persistent reverse amblyopia (PEDIG 2009)

Answer 11

* atropine is not suitable for aphakic / pseudoaphakic children, patients with Down’s syndrome or those with a known history of cardiac disorders, raised IOP, narrow angles or known hypersensitivity to atropine or any component of the preparation

Answer 12

All patients aged 6 and above with no motor fusion should be evaluated with Sbisa bar or Bagolini filter bar prior to amblyopia treatment and monitored closely. If diplopia occurs then treatment should be stopped immediately. It should be noted that the Bagolini filter bar (filters 1-16) and Sbisa bar (filters 1-17) are not equivalent . Monitoring of suppression should be undertaken using the same bar at each visit * Filter 7 is most often used as the point at which treatment is stopped

Answer 13

* Amblyopia treatment should be tapered once optimum equal visual acuity obtained has been reached to reduce the risk of recurrence or reversing amblyopia. Most that did alternate started treatment before age 2. (Campos & Gulli 1985) 42% recurrence when treatment not reduced and only 14% when reduced from 6-8 to 2 hours before discontinuing. (PEDIG 2004) * No significant improvement in the amblyopic eye when occlusion dosage increased after 2 consecutive visits with full compliance with treatment and no change in refraction and fundus exam. * Failure to improve, or deterioration of acuity, within 4-6 months of the commencement of amblyopia therapy (when compliance is good), should prompt re-refraction and re-examination of fundus and possible further investigations. * Complaints of binocular diplopia = Definitely stop if density of suppression reduces with risk of intractable diplopia

Answer 14

* Questionnaire - focus group of patients, orthoptists and ophthalmologists * Children were hardly troubled by the patch when playing games on the computer, watching TV or colouring (item 5), whereas parents thought that they were really troubled (Fig. 1e). * Almost all children (54), could play well with other children when wearing the patch (item 6). * Most all children (57) were not laughed at or bullied by other children when wearing the patch (item 10), and almost all parents agreed (Fig. 1j) * Children’s quality of life during occlusion therapy is affected less than their parents think

Answer 15

Pupil responses should be checked to ensure the correct eye has been dilated. All parents or guardians to be given verbal and written information regarding the use and side effects atropine drops / ointment and a copy of the atropine information leaflet (Appendix IV). A copy may also be issued for the child’s school. Any patient experiencing an adverse reaction to atropine should be seen by a doctor, the event recorded in the notes with any unexpected effects being reported to the Medicines and Healthcare products Regulatory Agency (MHRA) via the Yellow Card Scheme immediately. i) locally: irritation, photophobia, transient stinging, hyperaemia, oedema, conjunctivitis, raised IOP. ii) systemically: ataxia, restlessness, hallucinations, dry mouth, difficulty swallowing or talking, flushing and dry skin, irregular heartbeat, palpitations, urinary urgency and retention, constipation, confusion, nausea, vomiting, giddiness. Systemic effects are more likely with drops than ointment.32

Answer 16

Any patient experiencing an adverse reaction to atropine should be seen by a doctor, the event recorded in the notes with any unexpected effects being reported to the Medicines and Healthcare products Regulatory Agency (MHRA) via the Yellow Card Scheme immediately.

Answer 17

1. Occlusion amblyopia *Amblyopia in the fellow eye caused by treatment *Most likely in total occlusion *Sometimes seen in atropine treatment *Reports of development after one week occlusion in children <18 months *Can occur up to 2 years old Prognosis: *VA can generally be recovered Treatment: *Stop treatment and swap to other eye with careful supervision 2. Interactable diplopia *Luckily rare *Older children without BSV potential *Density of suppression monitored during treatment *Binocular function monitored Prognosis *Generally - unlikely to persist Treatment *Stop treatment at first sign of diplopia+ don’t draw attention to it 3. Dissociation *Cases of latent or intermittent strabismus *More likely in >5 year olds *Those with inadequate motor fusion Prognosis: *Good likelihood of functional result Treatment: *Treatment stopped and patient monitored *May spontaneously restore BSV *Prisms to fuse diplopia then strength reduced *Surgery if persists 4. General * Allergic response to Patch or Atropine *Infection incubated by patch * Psycho-social implications - increased likelihood of bullying & stigmatisation *Danger socially due to disorientation

Answer 18

1. Stimulus-deprivation Amblyopia: *Most common cause is cataract *Most severe is unilateral congenital cataract *Removal of cataract within 6 weeks in unilateral and 10 weeks in bilateral *Correction with IOL or CL Prognosis: VA Reasonable – improves if cataract acquired early infancy rather than truly congenital but Stereopsis rare Treatment: Intensive total occlusion as soon as possible after optical correction *1 hour per day per month of child’s age (until 8 months) *>8 months: all waking hours every other day or ½ waking hours every day *Limitations in testing & monitoring VA accurately in this age group

Answer 19

*Monitor near and distance VA *Explain watching for alternation of strabismus to parents Prognosis: Already covered *Possible improvement in angle in ET patients post occlusion therapy *Some not then requiring strabismus surgery *Patching can reduce eccentric fixation – should be monitored regularly Treatment: Improvement to be gained from FT refractive error correction first *Occlusion still generally treatment of choice in departments *Total occlusion – varying durations *Increase in hours if no improvement *Swap treatments *Add optical penalisation *Atropine in nystagmus cases

Answer 20

*May be detected late - >5 years old *Preschool vision screening Prognosis: Still good – despite late diagnosis *Central fixation increases chances of 0.00 LogMAR Treatment : *Refractive adaptation *Patching or atropine *Consider CLs if marked anisometropia *High aniso-myopia tend to respond less well

Answer 21

*Aim to achieve useful VA with refraction Prognosis *Normal VA level rarely obtained *Improvement normally more gradual over 2-3 years Treatment *Constant glasses wear *Some non-tolerance more likely in older children

Answer 22

Video games, perceptual learning, refractive surgery

Answer 23

Emmatropisaion is the process by which the refractive state of the eye changes and is mostly complete by 3 years old, from birth. Its the reduction in mostly hypermetropia and astigmatism and can eradicate around +3.00 DS and +1.50 DC (astigmatism) Passive emmetropization refers to normal eye growth as eye size increases, power of optical components decreases and proportionally refractive error decreases. Active emmatropisation describes the visual feedback mechanism in the control of eye growth (feedback from eye which is blur and stimulates cortex to keep/stop growing the eye) The eye axial length elongates, the lens becomes thinner and the cornea becomes thinner. The cone cells elongate and migrate towards the centre of the retina to form the foveal pit and bunch closer together so there's less space for light to fall in-between and the signal getting lost. The Critical period is where vision and BV connections are being rapidly formed and this period lasts until roughly 2 y/o. Any disruption during this time can have a severe effect on the overall visual outcome. The sensitive period is when the visual system is still developing therefore disruptions can still have an effect on the overall visual outcome but are not as severe, and lasts up to 8-10 y/o. The earlier the deprivation, the more severe the visual loss. Amblyopia exists when the process of emmetropization has failed and one eye (or rarely both) have not developed the neural connections from the eye to the brain due to disruption to the visual system

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AMBLYOPIA + REFRACTIVE ADAPTATION + PATCHING + ATROPINE + EMMATROPISATION Flashcards

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