10/4/2016. Organic (systemic) Form deprivation (structural) Strabismic Refractive Isometric Anisometric

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1 Marc B. Taub, OD, MS, FAAO, FCOVD Chief, Vision Therapy and Rehabilitation Southern College of Optometry Editor in Chief, Optometry & Visual Performance A difference in the VA of the two eyes of at least two lines of acuity. An absolute reduction of the VA between the two eyes. VA poorer than 20/20 in the absence of underlying structural or pathologic anomalies, but with at least one of its causes occurring before age 6. Very limited definition that does not take into account other measures Organic (systemic) Form deprivation (structural) Strabismic Refractive Isometric Anisometric Voluntary (malingering) Involuntary (nonmalingering) Hysterical Streff syndrome Characteristics of Acuity Acuity improves with letter isolation Crowding effect End letters are more easily identified Letters are read out of order Omission or addition of letters. Isolate the letters as single or one line only. Functional Organic Neutral Density Filter Normal Decrease Marked Decrease Telescope effect with 2.5 X Disproportionate Improvement Color vision Normal Abnormal Expected Improvement Amsler Grid Normal Abnormaldistortion/scotoma Haidinger Brush Normal Abnormal ERG Normal Abnormal VEP Normal Abnormal latency and waveform Positive Negative Type Functional Organic Fixation Central Eccentric RDS Positive Global Negative Global Duration Short Long Patient Age Young Older Patient Attitude Motivated Unmotivated Laser Interferometry Better than VA Same or minimal improvement 1

2 Application of the optimal prescription Does this mean the most plus? Does this mean the most least plus to get the best acuity? Does this mean all the astigmatism? Does this mean all of the aniso? How do you determine the best RX? Adjunctive Occlusion How much per day? What type of occlusion? Bangerter foils Black patch Near activities? What has been studied? Older Children (7 to < 18 years) Effectiveness of treatment Recurrence Young children (3 to <7 years old) Patching vs. Atropine Patching dosage Atropine dosage Recurrence Long-term follow up Glasses alone for anisometropic and strabismic amblyopia Benefits of occlusion Treatment of Bilateral Amblyopia A Randomized Trial of Prescribed Patching Regimens for Treatment of Severe Amblyopia in Children Ophthalmology 2003;110: Objective: To compare full-time patching (all hours or all but 1 hour per day) to 6 hours of patching per day, severe amblyopia in children younger than 7 years. Participants: One hundred seventy-five children younger than 7 years- 20/100 to 20/400. Intervention: full-time patching (all hours or all but 1 waking hour) 6 hours of patching per day, At least 1 hour of near-visual activities during patching. Main Outcome Measure: Visual acuity in the amblyopic eye after 4 months. Mean improvement from baseline Mean Acuity at 4 months 6 hours (n=73) Full time (n=84) 4.8 lines 4.7 lines 20/50 20/50-2 Results: Visual acuity in the amblyopic eye improved a similar amount in both groups. (P=0.45) Conclusion: NO DIFFERENCE! 2

3 A Randomized Trial of Patching Regimens for Treatment of Moderate Amblyopia in Children Arch Ophthalmol. 2003;121: Objective: To compare 2 hours vs. 6 hours of daily patching, moderate amblyopia (20/40 to 20/80) in children younger than 7 years. Methods: patching combined with at least 1 hour per day of near visual activities. Main Outcome Measure: Visual acuity in the amblyopic eye after 4 months. Results: Visual acuity improved an average of 2.40 lines in each group, P=.98. The 4-month visual acuity was at least 20/32 and/or improved from baseline by 3 or more lines in 62% of patients in each group (P=.99). Conclusion: NO DIFFERENCE A Randomized Trial of Increasing Patching for Amblyopia Increase from 2 to 6 hours in children with stable residual amblyopia (20/32-20/60) 169 children Aged 3 to <8 Stable residual amblyopia after 2 hours of daily patching for at least 12 weeks. Ten week outcome 6-hour group-1.2 line improvement 2-hour group-0.5 line improvement P=0.002 Improvement in 2 or more lines: 6-hour group-40% 2-hour group-18% P=0.003 A Randomized Trial Comparing Bangerter Filters and Patching for the Treatment of Moderate Amblyopia in Children What is a Bangerter foil? Degrees of occlusion Peripheral fusion To determine whether VA improvement with Bangerter foils is similar to improvement with patching as initial therapy in children with moderate therapy. 186 Children Aged 3 to < 10 years old Moderate amblyopia (20/40-20/80) Two groups Patching-2 hours a day Bangerter foil for full time use-either: 0.3 for 20/40 to 20/ for 20/80 3

4 At 24 weeks: Bangerter group-1.9 line improvement Patching group-2.3 line improvement Greater than or equal to 3 line improvement Bangerter group-38% Patching group-35% P= /25 or better VA Bangerter group-36% Patching group-31% P=0.86 Rate of improvement Not significant Lower burden with Bangerter foil 6 week P= week P<0.001 Compliance questionnaire 6 week P= week P=0.001 Bangerter associated with better compliance Social stigma treatment subscale 6 week P< week P<0.001 A Randomized Trial of Atropine Versus Patching for Treatment of Moderate Amblyopia in Children A single masked multi-center clinical trial Methods: 2 treatment groups Patching 6 hours to full time with near activities Atropine 1% I drop daily Primary outcome: Visual acuity at 6 months Outcomes Mean improvement from baseline Patching 6 months Atropine 6 months Patching (n=188) at 2 years Atropine (n=175) at 2 years 3.16 lines 2.84 lines 3.7 lines 3.6 lines Mean acuity 20/30 20/ / / /30 or 3 line improvement 79% 74% 86% 83% Summary Substantial improvement with both treatments Improvement occurred more rapidly in the patching group Small difference (1/3 of a line) at six months NO DIFFERENCE between groups in acuity after 2 years A Randomized Trial of Atropine Regimens for Treatment of Moderate Amblyopia in Children Ophthalmology 2004;111: Objective: To compare daily atropine to weekend atropine for moderate amblyopia (20/40 to 20/80)in children younger than 7 years. Participants: One hundred sixty-eight children younger than 7 years Amblyopia in the range of Associated with strabismus, anisometropia, or both. Intervention: daily atropine weekend atropine Main Outcome Measure: Visual acuity (VA) in the amblyopic eye after 4 months. 4

5 Results: The improvement in VA averaged 2.3 lines in each group. The VA of the amblyopic eye at study completion was either: (1) at least 20/25 or (2) better than or equal to that of the sound eye: 39 children (47%) in the daily group 45 children (53%) in the weekend group. Stereoacuity outcomes were similar in the 2 groups. Adverse effects: Light sensitivity Daily group-16% Weekend group-29% Conclusions: NO DIFFERENCE Recurrence after cessation of patching/atropine- One year follow up Recurrence was considered 1/3 of the treatment effect. Patching-25% Atropine-21% Recurrence factors 4 X recurrence in those without a gradual tapper Better VA at treatment end Greater improvement-number of lines Previous TX Study of Near Activities Versus Non-Near Activities During Patching Therapy for Amblyopia Objectives: Whether children randomized to near or non-near activities would perform prescribed activities. Combined with 2 hours of daily patching. Methods: 3 to less than 7 years of age, with anisometropic, strabismic, or combined amblyopia (20/40 to 20/400) 2 hours of daily patching with near activities 2 hours of daily patching without near activities. Results: At 8 wks: improvement in amblyopic eye Distance activity: 2.6 lines Near activity: 2.5 lines Similar for both groups, even at 17 wks. Near activities do not improve VA outcome in anisometropic, strabismic, combined amblyopia with 2 hrs of daily patching 5

6 Feasibility of a Clinical Trial of Vision Therapy for Treatment of Amblyopia 19 subjects recruited, seven sites 256 treatment visits 16 weeks of weekly in-office VT Active VT or placebo therapy All groups: 2 hours of patching 30 min of near activities 30 min of home computer therapy So, what happened? Met with great difficulty Poor recruitment Patching 2 hours is just as good as 6 hours. Atropine is as effective as patching in young children Glasses often get us a few lines of acuity Most improvement will come in the first 6 months of treatment Recurrence is more likely if treatment is stopped abruptly. Wean your patients Cut by 50% and FU in 6 weeks Cut by 50% and FU in 6 weeks Stop treatment and FU in 6 weeks. A binocular disorder is the primary disorder and amblyopia is the consequence. Rather than emphasizing patching, which may further disrupt binocular function Re-establish binocular function and stereopsis. Re-establishing binocular fusion requires a reduction of suppression Robert Hess and colleagues The use of global motion stimuli presented in front of each eye. Nine adults (24-29 yo) 20/40-20/400-4/9 previously treated with patching. Training ranged from 1 to 3 hours a day over several weeks (20-60 hours) Degree of suppression reduced to the point that the images could be combined VA in the amblyopic eye (P<0.008) and stereoacuity (P=0.012)improved significantly Can a game help in treating amblyopia? Tetris Amblyopic eye-blocks are high, fixed contrast Fellow eye-blocks are low, variable contrast As the game is played successfully, the contrast seen in the fellow eye is gradually increased until the same as the amblyopic eye. Information is then being combined from both eyes This indicates a reduction in suppression. 14 amblyopes (13-50 yo) Strabs, anisometropes and to mixed cases) Home-based study hours of game play 13 of 14 cases Restored simultaneous binocular perception Significant improvement in acuity (20/45 20/35) Significant improvement in stereoacuity (1388 sec 344 sec) 6

7 Therapy Monocular Bi-ocular Sherman playing cards, MFBF matching game Binocular Oculomotor Fixations, pursuits and saccades Accommodative Loose lens sorting, lens rock, MFBF matching game Vergence Vectograms, aperture rule, computer therapy 8 year old white male Referred from a local optometrist for a full examination decreased visual acuity at distance and near in the left eye with a possible diagnosis of amblyopia. Failed a school vision screening Headaches after long periods of reading, and that both eyes were getting tired with reading. Struggles with standardized testing and reading. Medical history was unremarkable. The family history was negative for strabismus and amblyopia. Birth history was traumatic. He was delivered via caesarian section after fetal distress. He was a blue baby and received oxygen but was not intubated. He had average birth weight. VA Distance (no correction) 20/20 OD, 20/200 OS 20/20 OU (Snellen-single line) VA Near 20/20 OD, 20/100 OS, OU (Snellen-single line) EOMS: Full and Smooth OD/OS Stereo: Global-No forms appreciated NPC: TTN X 3 Cover Test: Distance 3XP-Poor fixation noted OS Near 4 XP-Poor fixation noted OS Worth 4 Dot: shallow suppression at D & N Retinoscopy: OD -0.25D 20/20, OS +3.00D 20/100 Manifest refraction: OD +0.25D20/20, OS D 20/100+2 Cycloplegic refraction: OD, OS Visuoscopy: Central steady fixation OU What is the diagnosis? What Rx would you prescribe? What is your treatment plan for this patient? Does your treatment change if the BCVA with the RX is 20/50? 7

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