Resumen

FERNANDEZ ARGONES, Liamet et al. Structural characteristics of the optic disc and the neuroretinal nerve fiber layer observed by confocal laser tomography in suspected primary angle closure. Rev Cubana Oftalmol [online]. 2012, vol.25, suppl.1, pp. 374-386. ISSN 0864-2176.

Objective: to evaluate the characteristics of the optic disc and of the retinal nerve fiber layer in the suspected primary angle closure, the performance of glaucomatous discriminant functions, and the influence of the optic disc size in the results. Methods: a cross-sectional case series study in 47 eyes (30 patients) with suspected primary angle-closure, for which the confocal laser tomography (HRT 3, Heidelberg Engineering, Germany), was used to obtain the images. The influence of the optic disc size was analized in 3 groups: < 1,6mm², 1,6 - 2,0 mm² y > 2,0 mm². Results: the disc area was positively related to the cup area, the rim area, the cup volume, the retinal nerve fiber layer cross sectional area, and the cup size (p=0,023, p=0,009, p=0,022, p=0,026, p=0,020 respectively) and negatively related with the horizontal curvature of the retinal nerve fiber layer (p=0,019). There was a significant relation to the variation of contour height (p=0,008), particularly to differences between small and medium size discs. Discriminant functions such as MRA, GPS and FSM performed better in small discs (approximately 92 % of agreement with the normal discs for each one). The RB function obtained the greater coincidence (100, 96 and 100 % for respective groups of disc areas), whereas GPS obtained the smallest (92, 72 and 55,6 % respectively). Conclusions: the disc area is related to cup area, rim area, cup volume, retinal nerve fiber layer cross sectional area, retinal nerve fiber layer horizontal curvature, cup size and the variation of contour height. The MRA, GPS and FSM discriminant functions identify better the normal optic disc when it is small. The RB function performs the best whereas the GPS performs the worst, regardless of the disc area.

Palabras clave : suspected primary angle closure; confocal laser scanning; discriminant glaucomatous functions.