Effect Of Intraocular Gas Tamponade On Postoperative Intraocular Lens Position After Phacovitrectomy And The Influence Of Intraocular Lens Type

Published 2026 - 44th Congress of the ESCRS

Reference: POCAT543 | Type: Free paper | DOI: 10.82333/5x80-zc33

Authors: Dr Makoto Hayashi* ¹ , Dr So Goto ¹ , Dr Akihiko Shiraki ¹ , Dr Gen Nakao ¹ , Dr Masaki Suzue ¹ , Dr Susumu Sakimoto ¹ , Dr Kentaro Nishida ¹ , Dr Masaki Kinoshita ¹ , Prof. Dr Takatoshi Maeno ¹ , Prof. Dr Kohji Nishida ²

¹Department of Ophthalmology,Osaka University Graduate School,Suita,Japan, ²Department of Ophthalmology,Osaka University Graduate School,Suita,Japan;Integrated Frontier Research for Medical Science Division, Institute for Open and Transdisciplinary Research Initiatives (OTRI),The University of Osaka,Suita,Japan

Purpose

Intraocular gas tamponade during combined phacoemulsification and pars plana vitrectomy (PPV) may transiently increase posterior segment pressure and theoretically induce anterior displacement of the intraocular lens (IOL). However, its influence on postoperative IOL position at one month and potential differences between IOL models remain unclear. This study evaluated the effect of gas tamponade on postoperative anterior chamber depth (post-ACD) and examined whether the impact differs between two different 1-piece IOLs.

Setting

This single-center clinical study was conducted at The University of Osaka Hospital, Osaka, Japan. Medical records of consecutive patients who underwent phacovitrectomy between June 2024 and February 2026 were reviewed. Indications for phacovitrectomy include epiretinal membrane (ERM), macular hole (MH), vitreomacular traction syndrome (VMTS), vitreous opacity (VO), vitreous hemorrhage (VH), proliferative diabetic retinopathy (PDR), and rhegmatogenous retinal detachment (RRD).

Methods

This retrospective study included 75 eyes undergoing combined phacovitrectomy, divided into gas tamponade (Gas, n=51) and no gas (no Gas, n=24) groups. Two IOL models were implanted: Simplicity (AMO, n=36) and NSP2 (NIDEK, n=39). The primary outcome was post-ACD measured by anterior segment Optical Coherence Tomography (OCT) at 1 month. Baseline characteristics including age, axial length, average keratometry, preoperative ACD, and sex were compared between groups. Multivariable linear regression analysis was performed to adjust for potential confounders and to evaluate interaction between gas use and IOL type.

Results

Overall, post-ACD was 4.27 ± 0.33 mm in the Gas group and 4.34 ± 0.27 mm in the no Gas group, demonstrating a mean difference of −0.07 mm (p=0.329), suggesting a slight but non-significant anterior shift with gas tamponade. In the Simplicity subgroup, values were 4.30 ± 0.33 mm (Gas) and 4.38 ± 0.33 mm (no Gas), with a mean difference of −0.08 mm (p=0.54). In the NSP2 subgroup, values were 4.24 ± 0.33 mm (Gas) and 4.31 ± 0.23 mm (no Gas), with a mean difference of −0.08 mm (p=0.40). Multivariable analysis revealed no independent effect of gas tamponade (p=0.67) and no significant interaction between gas use and IOL type (p=0.58).

Conclusions

Intraocular gas tamponade was associated with a minimal trend toward anterior IOL displacement of approximately 0.07–0.08 mm at one month postoperatively. The observed difference in post-ACD corresponds to an estimated refractive impact of less than 0.1 D, suggesting limited clinical significance. Although no substantial difference was observed between the two IOL models evaluated in this study, numerous IOL designs with varying structural characteristics are currently available, and model-specific effects cannot be excluded. Given the relatively small sample size, further investigation in larger cohorts is warranted.