Filtering bleb classifications
The bleb is the functional part of trabeculectomy, and the part that largely determines long-term success, failure, and complications. In many studies authors have described bleb appearance after glaucoma surgery in terms of recognized patterns of bleb appearance such as cystic, encysted, flat, and diffuse, usually in conjunction with a global vascularity assessment. Article describes all proposed bleb grading systems: the old ones (Kronfeld, Migdal, Hitchings, Vesti, Lederer and Shingleton), the most popular (Wuerzburg bleb classification score, Indiana bleb appearance grading scale, Moorfields bleb grading system). Also analyzed the modern concepts of bleb morphology using ultrasound biomicroscopy, optical coherence tomography, thermography and digital methods for assessing hyperemia level. In conclusion, the author tried to determine the role of each classification. Which characteristics are to be used as a descriptive, and which of them can predict the duration of the hypotensive effect of the surgery.