Filtering blebs structure and function evaluation using optical coherence tomography

Daiva Paulaviciute-Baikstiene, Renata Vaiciuliene, Ingrida Januleviciene


Purpose: To assess the ability of a noncontact optical coherence tomography to evaluate the morphological features of filtering blebs one year after glaucoma surgery.

Design: Prospective study.

Methods: Eighteen patients (18 eyes) with diagnosed primary open-angle glaucoma (POAG) assigned for trabeculectomy were included in the 12-month study carried out in the Eye clinic of the Lithuanian University of Health Sciences. All participants underwent trabeculectomy with 5-fluorouracil (5-FU). Bleb function was considered to be successful if the intraocular pressure (IOP) was ≤ 18 mmHg without glaucoma medications and a limited success if: 18 < IOP ≤ 21 mmHg with or without glaucoma medications at 12 months after surgery. The filtering blebs were imaged by anterior segment optical coherence tomography (AS-OCT) to evaluate the bleb wall reflectivity and measured bleb structures 12 months after trabeculectomy. Level of significance: p < 0.05 was considered significant.

Results: The mean preoperative IOP was 25.7 (6.5) mmHg and the mean number of topical glaucoma medications was 3.0 (1.2). After surgery the mean IOP was 13.8 (3.4) mmHg and glaucoma medication was 0.3 (1.0) (Wilcoxon test, p < 0.001). Analyzing bleb morphology and bleb function it was found that with uniform wall reflectivity 0 out of 3 eyes (0%) had successful bleb function and with multiform wall reflectivity 14 out of 15 eyes (93.3%) had successful bleb function 12 months after surgery (p = 0.005).We found positive correlation between IOP changes and bleb wall thickness, height of internal fluid-filled cavity (bleb height) and total bleb height (r = 0.875, 0.897, 0.939, p < 0.001).

Conclusion: AS-OCT is a useful device to assess the structure of the filtering bleb. Larger internal fluid-filled cavity, total bleb height, bigger bleb wall thickness and multiform bleb wall reflectivity were found to be good indicators of bleb function.


AS-OCT, intraocular pressure, filtering bleb, primary open-angle glaucoma, trabeculectomy

Full Text:



Cairns JE. Trabeculectomy. Preliminary report of a new method. Am J Ophthalmol 1968; 66:673-79.

Wells AP, Crowston JG, Marks J, Kirwan JF, Smith G, Clarke JC, et al. A pilot study of a system for grading of drainage blebs after glaucoma surgery. J Glaucoma 2004;13:454‑60.

Nakano N, Hangai M, Nakanishi H, Inoue R, Unoki N, Hirose F, Ojima T, Yoshimura N. Early trabeculectomy bleb walls on anterior-segment optical coherence tomography. Graefes Arch Clin Exp Ophthalmol 2010 Aug; 248(8):1173-82.

Ciancaglini M, Carpineto P, Agnifili L, et al. Filtering bleb functionality: a clinical, anterior segment optical coherence tomography and in vivo confocal microscopy study. J Glaucoma. 2008; 17:308-17.

Pfenninger L, Schneider F, Funk J. Internal reflectivity of filtering blebs versus intraocular pressure in patients with recent trabeculectomy. Invest Ophthalmol VisSci. 2011; 52: 2450-5.

Picht G, Grehn F. Classification of filtering blebs in trabeculectomy: biomicroscopy and functionality. Curr Opin Ophthalmol. 1998; 9:2-8.

Hirooka K, Takagishi M, Baba T, Takenaka H, Shiraga F. Stratus optical coherence tomography study of filtering blebs after primary trabeculectomy with a fornix-based conjunctival flap. Acta Ophthalmol. 2010; 88:60-4.

Babighian S, Papizzi E, Galan A. Stratus-OCT of filtering bleb after trabeculectomy. Acta Ophthalmol Scand. 2006; 84:270-1.

Savini G, Zanini M, Barboni P. Filtering blebs imaging by optical coherence tomography. Clin Experiment Ophthalmol. 2005; 33:483-9.

Singh M, Chew PT, Friedman DS, et al. Imaging of trabeculectomy blebs using anterior segment optical coherence tomography. Ophthalmology. 2007; 114:47-53.

Hu CY, Matsuo H, Tomita G, et al. Clinical characteristics and leakage of functioning blebs after trabeculectomy with mitomycin-C in primary glaucoma patients. Ophthalmology 2003; 110:345–52.

DeBry PW, Perkins TW, Heatly G, et al. Incidence of late onset bleb-related complications following trabeculectomy with mitomycin. Arch Ophthalmol 2002; 120:297–300.

Soltau JB, Rothman RF, Budenz DL, et al. Risk factors for glaucoma filtering bleb infections. Arch Ophthalmol 2000; 118: 338–42.

Ernesto Golez III and Mark Latina. The Use of Anterior Segment Imaging after Trabeculectomy. Seminars in Ophthalmology 2012; 27:155–159.

Mayuri B Khamar, Shruti R Soni, Siddharth V Mehta, Samaresh Srivastava, Viraj A Vasavada. Morphology of functioning trabeculectomy blebs using anterior segment optical coherence tomography. Indian J Ophthalmol. 2014 Jun; 62(6):711-4.

Singh M, See JL, Aquino MC, Thean LS, Chew PT. High-definition imaging of trabeculectomy blebs using spectral domain optical coherence tomography adapted for the anterior segment. Clin Experiment Ophthalmol. 2009 May; 37(4):345-51.

Yamamoto, T, Sakuma, T, Kitazawa, Y. An ultrasound biomicroscopic study of filtering blebs after mitomycin C trabeculectomy. Ophthalmology 1995;102:1770-1776.

McWhae, JA, Crichton, AC. The use of ultrasound biomicroscopy following trabeculectomy. Can J Ophthalmol 1996;31:187-191.

Avitabile, T, Russo, V, Uva, MG. Ultrasound-biomicroscopic evaluation of filtering blebs after laser suture lysis trabeculectomy. Ophthalmologica 1998; 212:17-21.

Jinza, K, Saika, S, Kin, K, Ohnishi, Y. Relationship between formation of a filtering bleb and an intrascleral aqueous drainage route after trabeculectomy: evaluation using ultrasound biomicroscopy. Ophthalmic Res 2000; 32:240-243.

Savini, G, Zanini, M, Barboni, P. Filtering blebs imaging by optical coherence tomography. Clin Experiment Ophthalmol 2005; 33:483-489.

Babighian, S, Rapizzi, E, Galan, A. Stratus OCT of filtering bleb after trabeculectomy. Acta Ophthalmol Scand 2006; 84:270-271.

Müller, M, Hoerauf, H, Geerling, G, Pape, S, Winter, C, Hüttmann, G, Birngruber, R, Laqua, H. Filtering bleb evaluation with slit-lamp-adapted 1310-nm optical coherence tomography. Curr Eye Res 2006; 31:909-915.

Leung, CK, Yick, DW, Kwong, YY, Li, FC, Leung, DY, Mohamed, S, Tham, CC, Chung-chai, C, Lam, DS. Analysis of bleb morphology after trabeculectomy with Visante anterior segment optical coherence tomography. Br J Ophthalmol 2007; 91:340-344.

Kawana, K, Kiuchi, T, Yasuno, Y, Oshika, T. Evaluation of trabeculectomy blebs using 3-dimensional cornea and anterior segment optical coherence tomography. Ophthalmology 2009; 116:848-855.

Addicks EM, Quigley HA, Green R, Robin AL. Histologic characteristics of filtering blebs in glaucomatous eyes. Arch Ophthalmol 1983; 101:795–8.

Devika. K DO, Girija. K MS, Sindhu. S DO. Analysis of bleb morphology after trabeculectomy with anterior Segment optical Coherence Tomography. Kerala Journal of Ophthalmology 2014 March; 26(1):48-52.

Zhang Y, Wu Q, Zhang M, Song BW, DU XH, Lu B. Evaluating subconjunctival bleb function after trabeculectomy using slit lamp optical coherence tomography and ultrasound biomicroscopy. Chin Med J. 2008; 121(14):1274-9.

Tominaga A, Miki A, Yamazaki Y, Matsushita K, Otori Y. The assessment of the filtering bleb function with anterior segment optical coherence tomography. J Glaucoma. 2010 Oct-Nov; 19(8):551–55.


  • There are currently no refbacks.

Copyright (c) 2016 Journal for Modeling in Ophthalmology