Abstract
Purpose: :
To evaluate the reproducibility of measurement of macular retinal nerve fiber layer thickness over time using spectral domain optical coherence tomography (SD-OCT), we compared earlier and later findings.
Participants: :
In 24 eyes of fourteen participants, macular retinal nerve fiber thickness was serially measured using RTVue-100® (Optovue, Inc., Fremont, CA, USA) with GCC program at Hiroshima University Hospital two or more times at intervals ranging from one month to two years. Patients were excluded if they had a history of episodes of IOP elevation exceeding 3mmHg or 20%, reflection error larger than +3.00D or -6.00D, or other retinochoroidal disease such changeable central macular structure or history of intraocular operations other than cataract surgeries.
Methods: :
We compared earlier and later findings. The results include measurements of various macular retinal fiber layers such as ganglion cell complex layer thickness (GCCT), outer retinal nerve fiber layer thickness (ORNFLT) and retinal nerve fiber layer thickness (RNFLT) and the reproducibility of those measurements was evaluated.
Results: :
The average age of participants was 57.8±19.2 yo. and the average MD of eyes was -10.97±10.48dB. The eyes measured had been diagnosed as normal, as having giant disc or glaucoma. At the first measurement ORNFLT (average 164.67±16.69µm), RNFLT (average 241.39±21.76µm) and GCCT (average 76.71±14.90µm). Correlation of earlier and later findings for GCCT at the superior half was r2=0.87 (p<0.0001) and that at the inferior half was r2=0.95 (p<0.0001) and that of the average of the superior and inferior halves was r2=0.95 (p<0.0001). Correlation of earlier and later findings for ORNFLT at the superior half was r2=0.38(p=0.0014) and that at the inferior half was r2=0.44 (p=0.0008) and that of the average of the superior and inferior halves was r2=0.52 (p=0.0001). Correlation of earlier and later findings for RNFLT at the superior half was r2=0.44 (p=0.0004) and that at the inferior half was r2=0.54 (p<0.0001) and that of the average of the superior and inferior halves was r2=0.48 (p=0.0002).
Conclusions: :
On serial measurements of macular nerve fiber layer thickness using SD-OCT, the earlier and later findings of the GCC layer and outer part and full retina showed good correlation, indicating good reproducibility.
Clinical Trial: :
www.umin.ac.jp/ctr/index/htm UMIN000002841
Keywords: imaging/image analysis: clinical • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • ganglion cells