Efficacy of occlusion therapy initiated in patients with untreated amblyopia between twelve and forty years of age is effective.
ID
Bron
Verkorte titel
Aandoening
Rationale:
Amblyopia, defined as loss of visual function, caused by strabismus, anisometropia, and/or visual deprivation in the absence of ocular pathology, is commonly treated by occlusion therapy before age of six, limiting by the end of the sensitive period. However, recent studies suggest that the plasticity of the visual system extends into adolescents. In about a third of patients, 1% of the population, amblyopia persists in adulthood and thereby increasing the risk of bilateral visual impairment due to loss of vision in the nonamblyopic eye. This leads to decrease in quality of life and to increase costs to the healthcare system. The efficacy of occlusion therapy in adult patients, thus, whether visual improvement after treatment remains or decreases after occlusion is discontinued, is insufficiently investigated prospectively. Whether psychological factors or decreasing plasticity limits treatment effect in amblyopic adults is not clear.
Trefwoorden:
Amblyopie, effektiviteit, afplakbehandeling, visus
Amblyopia, efficacy, occlusion therapy, visual acuity
Ondersteuning
Onderzoeksproduct en/of interventie
Uitkomstmaten
Primaire uitkomstmaten
1. Improvement of visual acuity in LogMAR, from best-corrected visual acuity (after refractive adaptation) of the amblyopic eye at start to the end of occlusion therapy (maximal treatment effect);<br>
2. Response rate of treatment of the amblyopic eye, improvement of at least two lines from start to end of occlusion therapy.
Achtergrond van het onderzoek
Amblyopia, defined as loss of visual function, caused by strabismus, anisometropia, and/or visual deprivation in the absence of ocular pathology, is commonly treated by occlusion therapy before age of six, limiting by the end of the sensitive period. However, recent studies suggest that the plasticity of the visual system extends into adolescents. In about a third of patients, 1% of the population, amblyopia persists in adulthood and thereby increasing the risk of bilateral visual impairment due to loss of vision in the nonamblyopic eye. This leads to decrease in quality of life and to increase costs to the healthcare system. The efficacy of occlusion therapy in adult patients, thus, whether visual improvement after treatment remains or decreases after occlusion is discontinued, is insufficiently investigated prospectively. Whether psychological factors or decreasing plasticity limits treatment effect in amblyopic adults is not clear.
Doel van het onderzoek
Efficacy of occlusion therapy initiated in patients with untreated amblyopia between twelve and forty years of age is effective.
Onderzoeksopzet
After the enrolment, each patient is prescribed optical correction (if needed). Patients are seen at 6 weeks intervals (within a time window of ±1 week) up to 18 weeks (end of period of refractive adaptation).
After refractive adaptation, each patient will receive part-time occlusion on the sound eye until there is no further improvement (less than one LogMAR line) of visual acuity of the amblyopic eye, for a period of maximal 18 weeks. Patients are tested within 6 weeks intervals.
To determine the rate of recurrence following successful treatment (improvement of visual acuity at least two LogMAR lines from start to end of occlusion therapy) after treatment is discontinued, patients are continued in an observation phase for nine months. Follow-up visits take place three, six and nine months after discontinuation of treatment.
Onderzoeksproduct en/of interventie
All patients are prescribed three hours per day of part-time occlusion on the sound eye for a period of maximal 18 weeks.
Publiek
Brigitte Simonsz-Toth
Den Haag 2501 CK
The Netherlands
+31 (0)70 3302932
btoth@bluewin.ch
Wetenschappelijk
Brigitte Simonsz-Toth
Den Haag 2501 CK
The Netherlands
+31 (0)70 3302932
btoth@bluewin.ch
Belangrijkste voorwaarden om deel te mogen nemen (Inclusiecriteria)
1. All patients between twelve and forty years of age, diagnosed with amblyopia associated with strabismus and/ or anisometropia (>1.0 D of spherical equivalent or >1.50 D difference in astigmatism in any meridian);
2. Visual acuity in the amblyopic eye at least 1.3 LogMAR, using best correction based on the results of a cycloplegic refraction performed within past two months.
Belangrijkste redenen om niet deel te kunnen nemen (Exclusiecriteria)
1. Previous treatment for amblyopia (includes occlusion, or pharmacological defocusing);
2. Ocular cause for reduced visual acuity;
3. Diminished acuity due to medication;
4. Brain damage, or trauma, neurological disorders, and eye muscle palsies;
5. Best corrected visual acuity in the amblyopic eye less than 1.3 LogMAR.
Opzet
Deelname
Opgevolgd door onderstaande (mogelijk meer actuele) registratie
Geen registraties gevonden.
Andere (mogelijk minder actuele) registraties in dit register
Geen registraties gevonden.
In overige registers
| Register | ID |
|---|---|
| NTR-new | NL2586 |
| NTR-old | NTR2711 |
| Ander register | ABR : 35519 |
| ISRCTN | ISRCTN wordt niet meer aangevraagd. |
Samenvatting resultaten
Loudon, SE., Passchier, J., Chaker, L., de Vos, S., Fronius, M., Harrad, RA., Looman, CW., Simonsz, B., Simonsz, HJ. (2009) Psychological causes of non-compliance with electronically monitored occlusion therapy for amblyopia. Br J Ophthalmol, 93(11), 1499-503.<br>
Fronius, M., Bachert, I., Lüchtenberg, M. (2009) Electronic monitoring of occlusion treatment for amblyopia in patients aged 7 to 16 years. Graefes Arch Clin Exp Ophthalmol, 1401-8.