correlation between filtering bleb clinical morphology, anterior segment optical coherence tomography findings, and intraocular pressure

purpose : to evaluate usefulness of anterior segment optical coherence tomography (as-oct) in evaluation of filtering bleb functionality and to correlate its findings with clinical bleb examination methods : in this cross-sectional, descriptive study 55 eyes with apparently functional bleb were evaluated. following a comprehensive ophthalmic examination, filtering bleb grading was performed based on indiana bleb appearance grading scale (ibags). the bleb was then imaged using as-oct. two radial and tangential scans were obtained. results : the mean age was 57.69±12.47 years and 29 cases (53%) were female. the mean number of glaucoma medication and intraocular pressure (iop) were 0.45±0.71 and 14.35±4.67 mmhg, respectively. on as-oct examination, the mean bleb height, bleb wall thickness, internal cavity height, posterior extension of the internal cavity were 1.5±0.47 mm, 1±0.4 mm, 0.59±0.28 mm, and 3.15±1.26 mm, respectively. the internal reflectivity was high in 15 cases (27%) and low in 40 cases (73%). there was a positive correlation between the bleb height, bleb wall thickness, and internal cavity height on as-oct and iop. also, a negative correlation between the posterior extension of the internal cavity and iop was noted. there was also a positive correlation between the higher iop and a high internal reflectivity. there has also been a positive correlation between the bleb height at ibags and bleb reflectivity at as-oct. we also found that there was a positive correlation between the bleb vascularity at ibags and internal reflectivity at as-oct. conclusion : as-oct seems to be a useful device in evaluation of filtering bleb function. it yields valuable information regarding the internal bleb structures, and its findings are correlated with clinical examination of filtering bleb.      iranian journal of ophthalmology 201123(4):21-28 © 2011 by the iranian society of ophthalmology