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Small palpebral fissure as a significant risk factor for glaucoma surgery failure
Okuzumi N, Mori S, Katakami K, Iwaki Y, Sakamoto M, Yamada-Nakanishi Y, Nakamura M.. medRxiv, 2026-05-28
Topic: Health services, long-term care and technology
Purpose To evaluate the impact of “not commonly considered risk factors” on glaucoma surgical outcomes. Methods This study included 339 eyes that underwent glaucoma surgery. Surgical procedures included microhook ab-interno trabeculotomy (µTLO), Preserflo ab-externo microshunt implantation, trabeculectomy (Trab), and Ahmed Glaucoma Valve (AGV) implantation. In addition to conventional background factors, we examined a set of “not commonly considered risk factors,” including very elderly age (≥85 years), avitreous status, aphakia, use of antithrombotic agents, difficulty attending frequent postoperative visits, small palpebral fissure, corneal endothelial dysfunction, poor vision in the fellow eye, dementia, hearing loss, mental illness, atopic dermatitis, pseudophacodonesis, glaucoma eye drop allergy, and conditions contraindicating β-blocker use. Surgical success was defined as intraocular pressure (IOP) ≤21 mmHg, ≥20% reduction from baseline, and no additional glaucoma surgery at 1 year. Logistic regression was performed to identify potential risk factors; significant factors were further evaluated using propensity score matching. Results Of the 339 cases, surgical success rates were 65% for µTLO, 82% for Preserflo, 91% for Trab, and 82% for AGV. Multivariate logistic regression identified two independent predictors of surgical failure: small palpebral fissure (odds ratio 2.52, p < 0.01) and hearing loss (odds ratio 3.94, p = 0.04). Propensity score matching of patients with small versus large palpebral fissures (111 per group) confirmed significantly worse postoperative outcomes in the small-palpebral-fissure group despite balanced baseline characteristics. Conclusion Small palpebral fissure is an independent and previously unnoticed risk factor for glaucoma surgical failure, affecting both minimally invasive and filtration procedures. Précis This study identifies small palpebral fissures as an independent risk factor for glaucoma surgery failure and highlights the clinical importance of evaluating under-recognised patient characteristics when planning surgical procedures.
Key findings
- Logistic regression was performed to identify potential risk factors; significant factors were further evaluated using propensity score matching.
- Results Of the 339 cases, surgical success rates were 65% for µTLO, 82% for Preserflo, 91% for Trab, and 82% for AGV.
- Propensity score matching of patients with small versus large palpebral fissures (111 per group) confirmed significantly worse postoperative outcomes in the small-palpebral-fissure group despite balanced baseline characteristics.
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Study details
- Participants339
- Evidence strengthLow
How this study scored 16/100
Preprint — not yet peer-reviewed. It scored 29 on the same rubric, but non-peer-reviewed sources are capped at 16, so it shows as 16. Scored zero for study design, effect reported and randomised / blinded because the record does not state it. We have no data on times cited, citations per year, impact for its field and year, cited by studies here, still being cited, senior author's track record, institution's track record and multi-centre collaboration, so those were left out: it earned 18 of the 62 points we could judge it on, which is 29 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 2 / 10 | Tier 4 — not a peer-reviewed journal (medRxiv) |
| Journal's citation record | 0 / 4 | Not a journal article, so the journal's record does not count |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 4 / 10 | Preprint — not yet peer-reviewed. Hosted on a preprint server. |
| How recent | 5 / 5 | 2026 — within 1 year(s) of the newest study here |
| Sample size | 2 / 4 | 339 participants |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | — / 7 | No citation count (not found in OpenAlex) — left out of this score |
| Citations per year | — / 5 | No citation count or no year — left out of this score |
| Impact for its field and year | — / 6 | No field-weighted citation impact (OpenAlex has none yet) — left out of this score |
| Cited by studies here | — / 6 | Not yet checked against this library's citation graph — left out of this score |
| Still being cited | — / 4 | No yearly citation counts — left out of this score |
| Senior author's track record | — / 4 | Senior author's record not available — left out of this score |
| Institution's track record | — / 3 | No institution listed in OpenAlex — left out of this score |
| Multi-centre collaboration | — / 3 | Institutions not listed — left out of this score |
| Indexed in PubMed | 1 / 2 | Not in PubMed, but has a DOI |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 18 / 62 | Scored on 12 of 20 parts. We have no data for the rest, so they are left out: 18 of the 62 points we could judge it on is 29 out of 100. |
| Total | 29 / 100 | Capped to 16 because this is not a peer-reviewed article. |
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Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record names 7 authors; APA and Vancouver show the first six, BibTeX and the downloads carry all of them. Check the citation against the original before you use it.
APA 7th
Okuzumi, N., Mori, S., Katakami, K., Iwaki, Y., Sakamoto, M., Yamada-Nakanishi, Y., et al. (2026). Small palpebral fissure as a significant risk factor for glaucoma surgery failure. medRxiv. https://doi.org/10.64898/2026.05.27.26354208
Vancouver
Okuzumi N, Mori S, Katakami K, Iwaki Y, Sakamoto M, Yamada-Nakanishi Y, et al. Small palpebral fissure as a significant risk factor for glaucoma surgery failure. medRxiv. 2026. doi:10.64898/2026.05.27.26354208.
BibTeX
@article{okuzumi2026-4246e032,
author = {Okuzumi, N. and Mori, S. and Katakami, K. and Iwaki, Y. and Sakamoto, M. and Yamada-Nakanishi, Y. and Nakamura, M.},
title = {{Small palpebral fissure as a significant risk factor for glaucoma surgery failure}},
journal = {medRxiv},
year = {2026},
doi = {10.64898/2026.05.27.26354208},
url = {https://doi.org/10.64898/2026.05.27.26354208}
}