Factors associated with failure of parapapillary retinal nerve fiber layer segmentation in spectral-domain optical coherence tomography images.

摘要

Purpose : To identify factors associated with failure of automatic segmentation algorithm to detect parapapillary retinal nerve fiber layer (RNFL) boundary in spectral-domain optical coherence tomography (SDOCT) images. Methods : Parapapillary RNFL circle scans of consecutive cases imaged with SDOCT (RS3000, NIDEK co, Japan) were retrospectively reviewed. Images with low signal strength index (less than 6) were excluded. Segmentation failure was defined as inaccurate delineation of RNFL boundaries for more than 15 degrees as determined by visual inspection by a glaucoma specialist masked to clinical information. Relationship between segmentation failure and clinical factors were statistically evaluated with univariable and multivariable analyses. Results : Two hundred and twenty five eyes of 128 subjects were included. Sixty four subjects (50%) were female. Mean age ?± standard deviation was 58.3 ?± 16.4 years. One hundred and one eyes were primary open angle glaucoma or suspect, 37 eyes had optic neuropathy, 27 eyes were secondary glaucoma, 9 eyes were primary angle closure/glaucoma, and 33 eyes were healthy. Segmentation failure was found in forty nine eyes (21.7%). In univariable analyses, signal strength index, best-corrected visual acuity, disc area, and disease type were significantly associated with segmentation failure (P0.001, =0.017, 0.010, 0.016, respectively). In a multivariable logistic regression analysis, lower signal strength index, larger disc area, and disease types (primary open angle glaucoma and optic neuropathy) significantly increased the risk of segmentation failure (P0.001, =0.002, 0.044, 0.023, respectively). Other factors such as age, number of previous OCT examinations, intraocular pressure, refractive error, lens status, and history of intraocular surgeries were not significantly associated with segmentation failure. Conclusions : Segmentation failure was found in 21.7% of eyes that were imaged with SDOCT parapapillary RNFL scans. Low image quality, large disc area, primary open angle glaucoma, optic neuropathy, and low visual acuity were potential risk factors for segmentation failure. Physicians should cautiously check RNFL segmentation, especially in eyes with risk factors for segmentation failure. This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.