Japanese Journal of Ophthalmology

, Volume 61, Issue 6, pp 457–464 | Cite as

Effectiveness and safety of combined cataract surgery and microhook ab interno trabeculotomy in Japanese eyes with glaucoma: report of an initial case series

  • Masaki TanitoEmail author
  • Yoshifumi Ikeda
  • Etsuko Fujihara
Clinical Investigation



To report the early postoperative results and safety profile of ab interno microhook trabeculotomy (μLOT) combined with cataract surgery.

Patients and methods

This retrospective observational case series included 68 consecutive glaucomatous eyes of 23 Japanese men and 25 Japanese women [mean (SD) age, 76.0 ± 8.5 years] who underwent μLOT for intraocular pressure (IOP) and visually relevant cataracts. The LOT site/extent, perioperative complications, and complication treatments were collected from the medical and surgical records. The preoperative and postoperative IOP, numbers of antiglaucoma medications, logarithm of the minimum angle of resolution visual acuity (VA), anterior chamber (AC) flare, and corneal endothelial cell density (CECD) were compared.


After small incisional cataract surgery, the trabecular meshwork was incised in the nasal (6 eyes, 3.6 ± 0.5 clock hours), temporal (6 eyes, 3.8 ± 0.8 clock hours), or both nasal and temporal (56 eyes, 6.5 ± 0.6 clock hours) angles. The mean preoperative IOP (16.4 ± 2.9 mmHg) and number of antiglaucoma medications (2.4 ± 1.2) decreased significantly (P < 0.0001 and P = 0.0039, respectively) to 11.8 ± 4.5 and 2.1 ± 1.0 mmHg at 9.5 months postoperatively. Compared with the preoperative conditions, the final VA improved (P = 0.0002), the AC flare increased by 6.3 pc/ms (P = 0.0157), and the CECD decreased by 6% (P = 0.0005). Hyphema with niveau formation (28 eyes, 41%) and hyphema washout (6 eyes, 9%) were the most common postoperative complication and intervention, respectively. At the final visit, 54 eyes (79%) had achieved successful IOP control of 15 mmHg or less and IOP reduction of 15% or greater.


Combined μLOT and cataract surgery improves IOP and VA during the early postoperative period in patients with glaucoma and cataract.


Microhook ab interno trabeculotomy Minimally invasive glaucoma surgery Intraocular pressure Surgical complication Cataract surgery 


Conflicts of interest

M. Tanito, Grants (Inami), Lecture fees (Aeon Astron, Alcon, HOYA, JFC, Kowa, MSD, NIDEK, Novartis, Otsuka, Pfizer, Santen, Senju, Zeiss), Supply of microhooks (Inami); Y. Ikeda, Grants (Inami), Lecture fees (Santen), Supply of microhooks (Inami); E. Fujihara, Grants (Inami), Lecture fees (Kowa, Novartis), Supply of microhooks (Inami).

Supplementary material

Video 1. Microhook ab interno trabeculotomy combined with cataract surgery in the left eye. (MP4 47006 kb)


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Copyright information

© Japanese Ophthalmological Society 2017

Authors and Affiliations

  • Masaki Tanito
    • 1
    Email author
  • Yoshifumi Ikeda
    • 1
  • Etsuko Fujihara
    • 1
  1. 1.Division of OphthalmologyMatsue Red Cross HospitalMatsueJapan

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