Microtropia as an amblyopia indicator
Reviewed by Fiona Rowe

This study was undertaken to determine if microtropia with identity (straight eye anisometropia) is a reliable indicator of amblyopia following optical correction. This was a retrospective review of 532 children aged four to five years. After two months of glasses 190 had normal equal visual acuity (group 1). After four to six months of glasses wear 134 had normal visual acuity (group 2). None had amblyopia. Thirty had unequal visual acuity after six months of glasses wear and were deemed to have amblyopia (group 3). All had microtropia with identity. None was given occlusion, as visual acuities were 0.2 or better; 178 had unequal visual acuity after wearing glasses for six months and were given occlusion treatment (group 4). All achieved visual acuity of at least 0.3 after treatment. The authors acknowledge the importance of allowing full refractive adaptation of up to six months if visual acuity is improving. Sixty-one percent had equal visual acuity with glasses treatment alone. The remaining children were diagnosed with amblyopia and all had microtropia with identity. The authors conclude presence of microtropia with identity seems to be a reliable indicator of presence of amblyopia and the potential need for occlusion therapy in these cases

Is microtropia a reliable indicator of the presence of amblyopia in anisometropic patients?
Lysons D, Tapley J.
STRABISMUS
2018;26(3):118-21.