To compare 12-month clinical results of spatula-shaped and dual-blade microhooks ab interno trabeculotomy with phacoemulsification.
Retrospective comparative study.
We conducted a retrospective chart review of Japanese open-angle glaucoma patients who underwent ab interno trabeculotomy with phacoemulsification with a 12-month follow-up. Two types of trabecular hook were used: the spatula-shaped Tanito Trabeculotomy ab interno Micro-hook® and the Kahook Dual Blade®. Changes in intraocular pressure (IOP) and medication scores comprised the main outcome metrics. We also analyzed and compared patient demographics and the occurrence of complications.
Trabeculotomy was performed using a spatula-shaped hook in 17 eyes and a dual-blade hook in 15 eyes. Significant reductions in IOP (p < 0.001) and medication scores (p < 0.001) were noted in both groups after the 1-month time point. The percentage changes of IOP from baseline at each time point were not significantly different between groups, though there was a significant difference in medication scores at 12 months (p = 0.0192). Postoperative complications occurred similarly in both groups; one case in the dual-blade group required additional filtration surgery.
Ab interno trabeculotomy with phacoemulsification was effective in lowering IOP both with spatula-shaped and with double-blade microhooks. At 12 months more medications were used postoperatively in the spatula-shaped microhook group; however, the reductions in the medication scores from baseline were statistically significant in both groups.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
Tax calculation will be finalised during checkout.
Collaborative Normal-Tension Glaucoma Study Group. The effectiveness of intraocular pressure reduction in the treatment of normal-tension glaucoma. Am J Ophthalmol. 1998;126:498–505.
Collaborative Normal-Tension Glaucoma Study Group. The advanced glaucoma intervention study (AGIS): 7. the relationship between control of intraocular pressure and visual field deterioration. Am J Ophthalmol. 2000;130:429–40.
Heijl A, Leske MC, Bengtsson B, Hyman L, Bengtsson B, Hussein M. Early manifest glaucoma trial G: reduction of intraocular pressure and glaucoma progression: results from the early manifest glaucoma trial. Arch Ophthalmol. 2002;120:1268–79.
Musch DC, Gillespie BW, Niziol LM, Lichter PR, Varma R, Group CS. Intraocular pressure control and long-term visual field loss in the collaborative initial glaucoma treatment study. Ophthalmology. 2011;118:1766–73.
Inoue K, Ishida K, Tomita G, Noma H. A scoping review and network meta-analysis for efficacy and safety of glaucoma medication in Japanese patients. Jpn J Ophthalmol. 2020;64:103–13.
Musch DC, Gillespie BW, Palmberg PF, Spaeth G, Niziol LM, Lichter PR. Visual field improvement in the collaborative initial glaucoma treatment study. Am J Ophthalmol. 2014;158(96–104):e2.
Joh HJ, Jin SW. Comparison of different combinations of maximum medical therapy for lowering intraocular pressure in primary open angle glaucoma: 12-month retrospective consecutive case series. Jpn J Ophthalmol. 2019;63:322–7.
Sakata R, Yoshitomi T, Iwase A, Matsumoto C, Higashide T, Shirakashi M, et al. Lower normal pressure glaucoma study members in Japan glaucoma S: factors associated with progression of Japanese open-angle glaucoma with lower normal intraocular pressure. Ophthalmology. 2019;126:1107–16.
Komizo T, Ono T, Yagi A, Miyata K, Aihara M. Additive intraocular pressure-lowering effects of the Rho kinase inhibitor ripasudil in Japanese patients with various subtypes of glaucoma. Jpn J Ophthalmol. 2019;63:40–5.
Nakazawa T, Fukuchi T. What is glaucomatous optic neuropathy? Jpn J Ophthalmol. 2020;64:243–9.
Japan Glaucoma Society (2018) The Japan Glaucoma Society Guidelines for Glaucoma (4th Edition). Nippon Ganka Gakkai Zasshi 122:3–53. (in Japanese)
Tanihara H, Negi A, Akimoto M, Terauchi H, Okudaira A, Kozaki J, et al. Surgical effects of trabeculotomy ab externo on adult eyes with primary open angle glaucoma and pseudoexfoliation syndrome. Arch Ophthalmol. 1993;111:1653–61.
Honjo M, Tanihara H, Negi A, Hangai M, Taniguchi T, Honda Y, et al. Trabeculotomy ab externo, cataract extraction, and intraocular lens implantation: preliminary report. J Cataract Refract Surg. 1996;22:601–6.
Tanito M, Ohira A, Chihara E. Surgical outcome of combined trabeculotomy and cataract surgery. J Glaucoma. 2001;10:302–8.
Broadway DC, Grierson I, Hitchings RA. Local effects of previous conjunctival incisional surgery and the subsequent outcome of filtration surgery. Am J Ophthalmol. 1998;125:805–18.
Broadway DC, Chang LP. Trabeculectomy, risk factors for failure and the preoperative state of the conjunctiva. J Glaucoma. 2001;10:237–49.
Iwao K, Inatani M, Ogata-Iwao M, Takihara Y, Tanihara H. Restricted post-trabeculectomy bleb formation by conjunctival scarring. Graefes Arch Clin Exp Ophthalmol. 2009;247:1095–101.
Aihara M, Kuwayama Y, Miyata K, Ohtani S, Ideta R, Hashimoto Y, et al. Twelve-month efficacy and safety of glaucoma filtration device for surgery in patients with normal-tension glaucoma. Jpn J Ophthalmol. 2019;63:402–9.
Greenwood MD, Seibold LK, Radcliffe NM, Dorairaj SK, Aref AA, Roman JJ, et al. Goniotomy with a single-use dual blade: short-term results. J Cataract Refract Surg. 2017;43:1197–201.
Tanito M, Ikeda Y, Fujihara E. Effectiveness and safety of combined cataract surgery and microhook ab interno trabeculotomy in Japanese eyes with glaucoma: report of an initial case series. Jpn J Ophthalmol. 2017;61:457–64.
Tanito M, Sano I, Ikeda Y, Fujihara E. Short-term results of microhook ab interno trabeculotomy, a novel minimally invasive glaucoma surgery in Japanese eyes: initial case series. Acta Ophthalmol. 2017;95:e354–60.
ElMallah MK, Seibold LK, Kahook MY, Williamson BK, Singh IP, Dorairaj SK, Group KDBGS. 12-month retrospective comparison of kahook dual blade excisional goniotomy with istent trabecular bypass device implantation in glaucomatous eyes at the time of cataract surgery. Adv Ther. 2019;36:2515–27.
Dorairaj SK, Seibold LK, Radcliffe NM, Aref AA, Jimenez-Roman J, Lazcano-Gomez GS, et al. 12-month outcomes of goniotomy performed using the kahook dual blade combined with cataract surgery in eyes with medically treated glaucoma. Adv Ther. 2018;35:1460–9.
Dorairaj SK, Kahook MY, Williamson BK, Seibold LK, ElMallah MK, Singh IP. A multicenter retrospective comparison of goniotomy versus trabecular bypass device implantation in glaucoma patients undergoing cataract extraction. Clin Ophthalmol. 2018;12:791–7.
Mori S, Murai Y, Ueda K, Sakamoto M, Kurimoto T, Yamada-Nakanishi Y, et al. A comparison of the 1-year surgical outcomes of ab externo trabeculotomy and microhook ab interno trabeculotomy using propensity score analysis. BMJ Open Ophthalmol. 2020;5:e000446.
Falkenberry S, Singh IP, Crane CJ, Haider MA, Morgan MG, Grenier CP, et al. Excisional goniotomy vs trabecular microbypass stent implantation: a prospective randomized clinical trial in eyes with mild to moderate open-angle glaucoma. J Cataract Refract Surg. 2020;46:1165–71.
Omoto T, Fujishiro T, Asano-Shimizu K, Sugimoto K, Sakata R, Murata H, et al. Comparison of the short-term effectiveness and safety profile of ab interno combined trabeculotomy using 2 types of trabecular hooks. Jpn J Ophthalmol. 2020;64:407–13.
Baayen RH, Davidson DJ, Bates DM. Mixed-effects modeling with crossed random effects for subjects and items. J Mem Lang. 2008;59:390–412.
Bates D, Mächler M, Bolker B, Walker S. Fitting linear mixed-effects models Usinglme4. J Stat Softw. 2015;67:1.
Dunnett CW. A multiple comparison procedure for comparing several treatments with a control. Am Stat Assoc. 1955;50:1096–211.
Iwasaki K, Arimura S, Takamura Y, Inatani M. Clinical practice preferences for glaucoma surgery in Japan: a survey of Japan Glaucoma Society specialists. Jpn J Ophthalmol. 2020;64:385–91.
Chen PP, Lin SC, Junk AK, Radhakrishnan S, Singh K, Chen TC. The effect of phacoemulsification on intraocular pressure in glaucoma patients: a report by the American Academy of Ophthalmology. Ophthalmology. 2015;122:1294–307.
Cohen J. Statistical power analysis for the behavioral sciences. 2nd ed. Hillsdale: Lawrence Erlbaum; 1988. p. 1–17.
Lüdecke D: sjstats. Collection of Convenient Functions for Common Statistical Computations. 2020. Available at: https://cran.r-project.org/web/packages/sjstats/index.html. Accessed 2020 Augsut 8
Green P, MacLeod CJ, Nakagawa S. SIMR. an R package for power analysis of generalized linear mixed models by simulation. Methods Ecol Evol. 2016;7:493–8.
Conflicts of interest
T. Omoto, None; T. Fujishiro, None; K. A. Shimizu, None; K. Sugimoto, None; R. Sakata, Financial support (TOMEY, Santen, Alcon, Senju, Nitten, Kowa); H. Murata, None; R. Asaoka, None; M. Honjo, None; M. Aihara, Financial support (Novartis, Pfizer, Kowa, Otsuka, Wakamoto, Nitten, Johnson & Johnson, Glaukos, TOMEY, Ono, Crewt Medical Systems, Sato, Santen, Senju, Alcon), Consultant fee (Pfizer, Kowa, Otsuka, Wakamoto, HOYA, InnFocus, Glaukos, IRIDEX, Crewt Medical Systems, Astellas, Santen, Senju, Alcon), Lecture fee, Non-financial support (Novartis, Pfizer, Kowa, Otsuka, Nitten, Johnson & Johnson, HOYA, Glaukos, TOMEY, IRIDEX, Crewt Medical Systems, Canon, Zeiss, Sato, Santen, Senju, Alcon).
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Corresponding Author: Takashi Fujishiro
About this article
Cite this article
Omoto, T., Fujishiro, T., Asano-Shimizu, K. et al. Comparison of 12-month surgical outcomes of ab interno trabeculotomy with phacoemulsification between spatula-shaped and dual-blade microhooks. Jpn J Ophthalmol 65, 402–408 (2021). https://doi.org/10.1007/s10384-020-00806-4
- Intraocular pressure