In vivo imaging of lamina cribrosa pores by adaptive optics scanning laser ophthalmoscopy.

Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Investigative ophthalmology & visual science (Impact Factor: 3.43). 06/2012; 53(7):4111-9. DOI: 10.1167/iovs.11-7536
Source: PubMed

ABSTRACT To visualize and assess the surface-level pores of the lamina cribrosa in patients with glaucoma by using a prototype adaptive optics scanning laser ophthalmoscopy (AOSLO) system.
The numbers of laminar pores were compared between color disc photography, scanning laser ophthalmoscopy (SLO) without AO, and AOSLO. The pore area and elongation index were examined for correlation with ocular parameters such as the mean deviation, disc area, cup/disc ratio, disc ovality index, intraocular pressure (IOP), and axial length in the AOSLO images.
The 40 eyes (20 normal and 20 glaucomatous) of 40 subjects were enrolled. The AOSLO provided laminar pore images of better quality than other imaging methods, and the number of visible pores was significantly greater in the AOSLO images than in the other imaging methods (the color disc photographs [P < 0.001] and SLO without AO images [P < 0.001]) when compared for 26 subjects. When compared for 40 subjects using AOSLO, the pore area was significantly larger in glaucomatous subjects than in normal subjects (P = 0.031), but elongation index was not. The pore area correlated significantly with the axial length (P = 0.008) in normal subjects, with the untreated IOPs (P = 0.002) in the glaucomatous subjects, and with the axial length (P = 0.001) and cup/disc ratio (P = 0.012) in the total subjects. Via multiple regression analysis, significant correlations with pore area were found for axial length in the normal (β = 0.684, P = 0.001) and total subjects (β = 0.496, P < 0.001) and untreated IOP in the glaucomatous (β = 0.506, P = 0.023) and total subjects (β = 0.331, P = 0.014).
AOSLO is a useful imaging technology for assessing laminar pore morphology. The laminar pore area may be affected by axial length and IOP.

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