Laparoscopic sleeve gastrectomy positively affects ocular transparency

Turkish researchers reported significant positive changes in ocular transparency in the lens, cornea, and anterior segment in patients who underwent laparoscopic sleeve gastrectomy. Hüseyin Kaya, MD, and Muhammed Raşit Aykota, MD, from Pamukkale University’s Ophthalmology Department and Tekden Hospital’s General Surgery Department, respectively, both in Denizli, Turkey, published their findings in BMC Ophthalmology.¹

Obesity, they explained, can significantly affect ocular health, specifically the corneal epithelium and corneal sensitivity.² In addition, changes in the corneal hysteresis, corneal resistance factor, and intraocular pressure (IOP) in obese patients may indicate the risk of development of glaucoma.³ Other changes resulting from obesity include small nerve fiber damage and inflammation in corneal tissue,⁴ and there is an increased risk of age-related, cortical, and posterior subcapsular cataracts.⁵

Metabolic and bariatric surgery, which includes laparoscopic sleeve gastrectomy, has been reported to be highly effective for controlling weight loss over the long term.⁶ Some studies have already reported that metabolic and bariatric surgery can affect the retinal layers, choroid, ocular surface, and the IOP^7-10 as well as affect structural changes in the cornea in patients with keratoconus¹² and in the anterior segment.¹²

To increase the knowledge base about the effects of laparoscopic sleeve gastrectomy, the investigators evaluated the surgical effects on the lens and corneal densitometry, which had not yet been done.

In their prospective, single-center study, they investigated changes in those two parameters in obese patients before and 6 months after they underwent metabolic and bariatric surgery. The secondary study outcomes were the changes in the central corneal thickness (CCT), IOP, anterior chamber depth (ACD), and anterior chamber angle (ACA).

Pentacam topography (Oculus) was performed preoperatively and 6 months after laparoscopic sleeve gastrectomy to determine the surgical effects on the ocular parameters. A total of 58 patients (58 eyes; mean age, 36.76 years; average body mass index ([BMI], 43.4 ± 6.6 kg/m²) were included in the study.

What changes resulted from laparoscopic sleeve gastrectomy?

The authors reported that 6 months postoperatively, the average BMI decreased significantly to 31.54 ± 5.13 kg/m² (P < 0.001).

They also observed significant decreases in the CCT, IOP, and the corneal and lens densitometry values (P < 0.001 for all comparisons). The ACD and ACA significantly increased 6 months postoperatively (P < 0.001 for all parameters), they reported.

Kaya and Aykota commented, “This study demonstrated for the first time that laparoscopic sleeve gastrectomy is associated with significant reductions in the corneal and lens densitometry. These findings suggest that measurable changes in the optical density of ocular tissue may accompany substantial metabolic weight loss.”

However, despite their positive findings, they pointed out that these changes were limited in scope and the clinical relevance was uncertain, and therefore these findings should primarily be interpreted as physiologic observations. They suggested that larger studies with longer follow-up periods should be conducted to clarify the clinical significance of the densitometric changes and the underlying mechanisms.

References

1. Kaya H, Aykota MR. Effects of metabolic and bariatric surgery on corneal and lens densitometry. BMC Ophthalmol. 2026; published online May 13. https://doi.org/10.1186/s12886-026-04912-8

2. Courson JA, Rumbaut RE, Burns AR. Impact of obesity and age on mouse corneal innervation at the epithelial–stromal interface. Invest Ophthalmol Vis Sci. 2024;65:11. doi:10.1167/iovs. 65.5.11.

3. Aydin Eroglu S, Akyuz Unsal A, Verdi F, Kurt Omurlu I, Unuvar T, Anik A. The effect of childhood obesity on intraocular pressure, corneal biomechanics, retinal nerve fiber layer, and central macular thickness. J Glaucoma. 2024;33:417–21. doi:10.1097/IJG.0000000000002372.

4. Gulkas S, Aydin FO, Turhan SA, Toker AE. In vivo corneal confocal microscopy as a non-invasive test to assess obesity-induced small fibre nerve damage and inflammation. Eye (Lond). 2023;37:2226–32. doi:10.1038/s41433-022-02321-x.

5. Pan CW, Lin Y. Overweight, obesity, and age-related cataract: a meta-analysis. Optom Vis Sci. 2014;91:478–83.

6. Sjöström L, Peltonen M, Jacobson P. Bariatric surgery and long-term cardiovascular events. JAMA. 2012;307:56–65.

7. Laiginhas R, Guimarães M, Cardoso P, et al. Bariatric surgery induces retinal thickening without affecting the retinal nerve fiber layer, independent of diabetic status. Obes Surg. 2020;30:4877–84.A

8. Agarwal A, Saini A, Mahajan S, et al. Effect of weight loss on the retinochoroidal structural alterations among patients with exogenous obesity. PLoS One. 2020;15:e0235926.

9. Karimzad S, Bilkhu PS, Wolffsohn JS, et al. Impact of bariatric surgery-induced weight loss on anterior eye health in patients with obesity. Nutrients. 2022;14:2462. doi:10.3390/nu14122462.

10. Viljanen A, Hannukainen JC, Soinio M,et al. The effect of bariatric surgery on intraocular pressure. Acta Ophthalmol. 2018;96:849–52. doi:10.1111/aos.13826.

11. Greenberg JR, McCormick GJ. Regression of keratoconus after gastric sleeve surgery. Cornea. 2020;39:912–4. doi:10.1097/ICO.0000000000002286.

12. Toptan M, Elkan H, Erdogdu H, Goc O, Yilmaz OF. The effects of metabolic and bariatric surgery on the anterior segment parameters of the eye. Obes Surg. 2025;35:1234–41. doi:10.1007/s11695-025-07773-0.