150
D. Cabrera DeBuc et al.
gest a specific cause for an organic anomaly affecting the retina in amblyopia [189].
More recently, using a third-generation nerve fiber analyzer (GDx, Laser Diagnostic
Technologies, San Diego, CA), Colen et al. measured RNFL thickness in strabismic
amblyopia and reported no significant difference between amblyopic and sound eyes
[190]. In 2005, Altintas et al. carried out OCT examination on 14 unilateral strabismic
amblyopic patients and no difference was seen in macular and cpRNFL thickness
or macular volume [179]. Kee et al. enrolled 26 unilateral amblyopic children (6
strabismic, 15 anisometropic, 5 combined amblyopes), and found no difference in
cpRNFL in any of examined 4 quadrants (superior, inferior, nasal, temporal) and
foveal thickness between neither the amblyopic eye and fellow eye, nor between values of these amblyopic patients and 42 normal control children using TD-OCT [181].
However, they found statistically significant difference in mean thickness values of
the fovea and the RNFL of the amblyopic eyes of the children with anisometropic
amblyopia (n 15) and strabismic amblyopia (n 6) (146.5 vs. 173.1 µm p 0.046,
cpRNFL 112.9 vs. 92.8 µm p 0.034). They did not measure the AL, and in the
anisometropic group 10 of 15 children were myop.
Repka et al. completed studies in 2006 and 2009 evaluating 17 patients aged
5–28 years and subsequently 37 amblyopic children and found no difference in
cpRNFL thickness between amblyopic and sound eyes using TD-OCT [182, 183].
Similarly, in 2011, Walker et al. investigated 30 adults (mean age: 56 years) with
amblyopia (using Cirrus HD-OCT) and found no statistically significant difference
in RNFL thickness of any circumpapillary quadrants and macular thickness in any
anatomical location [184].
In 2004, Yen et al. used 2nd generation OCT to measure cpRNFL in 38 patients
(mean age 26.4, range 6–75 years) with unilateral amblyopia (strabismic and refractive amblyopia) and found no significant difference between strabismic amblyopic
and normal eyes [173]. However, the cpRNFL was significantly thicker in eyes
with refractive amblyopia compared with the fellow eye and the differences were
significant in the multivariate regression analysis as well with adjustment for AL,
spherical equivalent(SE), age and sex [173]. Yoon et al. had similar findings in a
study of 31 hyperopic anisometropic children regarding cpRNFL thickness (115.2
vs. 109.6 µm, p 0.019) but found no difference in mean macular retinal thickness
(252.5 vs. 249.7 µm) [174]. They did not measure the AL.
In the Sydney Childhood Eye Study, Huynh et al. tested 48 unilateral amblyopes
(17 strabismic, 19 hyperopic anisometropia) and reported that amblyopic eyes had
slightly greater foveal minimum thickness than the normal fellow eye (by 5.0 µm)
and the right eyes of non-amblyopic children (by 10 µm) [177]. This difference was
more pronounced in 6-year old children (6.9 µm) than 12–year old children (4.2 µm)
[177]. The IOD in foveal minimum thickness was greater in children who did not
receive any treatment for unilateral amblyopia [177]. Foveal minimum thickness
remained significantly greater in amblyopic than non-amblyopic eyes, after adjusting
for amblyopia severity and Interocular difference (IOD) in AL (p 0.01). In their
study the inner macular ring was significantly thinner in amblyopic children, and
there were no significant differences in outer macular ring thicknesses, central and
total macular volume or in cpRNFL [177].
D. Cabrera DeBuc et al.
gest a specific cause for an organic anomaly affecting the retina in amblyopia [189].
More recently, using a third-generation nerve fiber analyzer (GDx, Laser Diagnostic
Technologies, San Diego, CA), Colen et al. measured RNFL thickness in strabismic
amblyopia and reported no significant difference between amblyopic and sound eyes
[190]. In 2005, Altintas et al. carried out OCT examination on 14 unilateral strabismic
amblyopic patients and no difference was seen in macular and cpRNFL thickness
or macular volume [179]. Kee et al. enrolled 26 unilateral amblyopic children (6
strabismic, 15 anisometropic, 5 combined amblyopes), and found no difference in
cpRNFL in any of examined 4 quadrants (superior, inferior, nasal, temporal) and
foveal thickness between neither the amblyopic eye and fellow eye, nor between values of these amblyopic patients and 42 normal control children using TD-OCT [181].
However, they found statistically significant difference in mean thickness values of
the fovea and the RNFL of the amblyopic eyes of the children with anisometropic
amblyopia (n 15) and strabismic amblyopia (n 6) (146.5 vs. 173.1 µm p 0.046,
cpRNFL 112.9 vs. 92.8 µm p 0.034). They did not measure the AL, and in the
anisometropic group 10 of 15 children were myop.
Repka et al. completed studies in 2006 and 2009 evaluating 17 patients aged
5–28 years and subsequently 37 amblyopic children and found no difference in
cpRNFL thickness between amblyopic and sound eyes using TD-OCT [182, 183].
Similarly, in 2011, Walker et al. investigated 30 adults (mean age: 56 years) with
amblyopia (using Cirrus HD-OCT) and found no statistically significant difference
in RNFL thickness of any circumpapillary quadrants and macular thickness in any
anatomical location [184].
In 2004, Yen et al. used 2nd generation OCT to measure cpRNFL in 38 patients
(mean age 26.4, range 6–75 years) with unilateral amblyopia (strabismic and refractive amblyopia) and found no significant difference between strabismic amblyopic
and normal eyes [173]. However, the cpRNFL was significantly thicker in eyes
with refractive amblyopia compared with the fellow eye and the differences were
significant in the multivariate regression analysis as well with adjustment for AL,
spherical equivalent(SE), age and sex [173]. Yoon et al. had similar findings in a
study of 31 hyperopic anisometropic children regarding cpRNFL thickness (115.2
vs. 109.6 µm, p 0.019) but found no difference in mean macular retinal thickness
(252.5 vs. 249.7 µm) [174]. They did not measure the AL.
In the Sydney Childhood Eye Study, Huynh et al. tested 48 unilateral amblyopes
(17 strabismic, 19 hyperopic anisometropia) and reported that amblyopic eyes had
slightly greater foveal minimum thickness than the normal fellow eye (by 5.0 µm)
and the right eyes of non-amblyopic children (by 10 µm) [177]. This difference was
more pronounced in 6-year old children (6.9 µm) than 12–year old children (4.2 µm)
[177]. The IOD in foveal minimum thickness was greater in children who did not
receive any treatment for unilateral amblyopia [177]. Foveal minimum thickness
remained significantly greater in amblyopic than non-amblyopic eyes, after adjusting
for amblyopia severity and Interocular difference (IOD) in AL (p 0.01). In their
study the inner macular ring was significantly thinner in amblyopic children, and
there were no significant differences in outer macular ring thicknesses, central and
total macular volume or in cpRNFL [177].