Change in Corneal Endothelial Cells after Gonioscopy-Assisted Transluminal Trabeculotomy

Abstract

Purpose To examine the change in corneal endothelial cell density (ECD) after gonioscopy-assisted transluminal trabeculotomy (GATT) surgery alone or in combination with phacoemulsification (phaco).

Methods In this prospective monocentric comparative study, consecutive patients were enrolled with open angle glaucoma (OAG) and who had been treated with GATT or phaco + GATT, with complete endothelial cell data and at least 6 months of follow-up. Patients who underwent phaco surgery alone during the same period were recorded as the control group. The main outcomes were ECD changes.

Results The study included 64 OAG (40 eyes in the GATT and 24 eyes in the GATT + phaco groups) and 30 control eyes (phaco group). There was a significant decrease in mean ECD compared to baseline in the GATT, phaco + GATT, and phaco groups (p < 0.001 for all). At the end of follow-up, percent cumulative ECD reduction values were 6.89%, 14.47% and 10.32% in the GATT, phaco + GATT, and phaco groups, respectively (p = 0.01 for all groups). The ECD reduction in the phaco + GATT group (p = 0.02) and in the phaco group (p = 0.04) was significantly higher than in the GATT group. ECD reduction was similar in the phaco + GATT and phaco groups (p = 0.69).

Conclusions A significant ECD loss was observed in 6 months period after GATT surgery compared to the baseline. The ECD reduction observed after GATT combined with phacoemulsification was greater than with GATT alone. There was no significant difference between phaco-GATT combined surgery and phaco alone.

Zusammenfassung

Ziel Untersuchung der Veränderung der kornealen Endothelzelldichte (ECD) nach einer gonioskopiegestützten transluminalen Trabekulotomie (GATT) als alleinige Operation oder in Kombination mit einer Phakoemulsifikation (Phako).

Patienten/Methoden und Materialien In dieser prospektiven, monozentrischen Vergleichsstudie wurden konsekutive Patienten mit Offenwinkelglaukom (OAG) eingeschlossen, die mit GATT oder Phako + GATT behandelt wurden und vollständige Endothelzelldaten sowie eine Nachbeobachtungszeit von mindestens 6 Monaten aufwiesen. Patienten, die im selben Zeitraum ausschließlich einer Phako-Operation unterzogen wurden, dienten als Kontrollgruppe. Der primäre Endpunkt war die Veränderung der ECD.

Ergebnisse Die Studie umfasste 64 Augen mit OAG (40 Augen in der GATT-Gruppe und 24 Augen in der Phako + GATT-Gruppe) sowie 30 Kontrollaugen (Phako-Gruppe). In allen Gruppen wurde im Vergleich zum Ausgangswert ein signifikanter Rückgang der mittleren ECD festgestellt (p < 0,001). Am Ende der Nachbeobachtungszeit betrug der prozentuale kumulative ECD-Verlust 6,89% in der GATT-Gruppe, 14,47% in der Phako+GATT-Gruppe und 10,32% in der Phako-Gruppe (p = 0,01 für alle Gruppen). Der ECD-Verlust in der Phako + GATT-Gruppe (p = 0,02) und in der Phako-Gruppe (p = 0,04) war signifikant höher als in der GATT-Gruppe. Zwischen der Phako + GATT-Gruppe und der Phako-Gruppe bestand kein signifikanter Unterschied (p = 0,69).

Fazit Innerhalb eines Zeitraums von 6 Monaten nach der GATT-Operation wurde ein signifikanter Verlust der ECD im Vergleich zum Ausgangswert beobachtet. Der ECD-Verlust nach einer kombinierten GATT-Phakoemulsifikation war größer als nach einer alleinigen GATT-Operation. Zwischen der kombinierten Phako + GATT-Operation und der alleinigen Phako bestand kein signifikanter Unterschied.

Conclusion Box

Already known

• Endothelial cell density (ECD) loss in glaucoma occurs due to aging, glaucoma itself, treatments, and laser exposure.

• Minimally invasive glaucoma surgeries (MIGS) have been linked to ECD loss, but studies on gonioscopy-assisted transluminal trabeculotomy (GATT) remain limited.

• The long-term impact of GATT on ECD is still unclear.

Newly described

• Despite being a MIGS procedure, GATT caused a significant ECD reduction at six months.

• The ECD loss after GATT was comparable to that of standard phacoemulsification. Pseudoexfoliative glaucoma patients showed greater cumulative ECD loss than primary open angle glaucoma patients.

Keywords

cornea - glaucoma - cataract

Schlüsselwörter

Kornea - Glaukom - Katarakt

Publication History

Received: 07 December 2024

Accepted: 06 August 2025

Accepted Manuscript online:
07 August 2025

Article published online:
03 September 2025

• References

• 1 Kim DH, Wee WR, Hyon JY. The pattern of early corneal endothelial cell recovery following cataract surgery: cellular migration or enlargement?. Graefes Arch Clin Exp Ophthalmol 2015; 253: 2211-2216
• 2 Realini T, Gupta PK, Radcliffe NM. et al. The effects of glaucoma and glaucoma therapies on corneal endothelial cell density. J Glaucoma 2021; 30: 209-218
• 3 Choi JY, Han YK. Long-term (≥ 10 years) results of corneal endothelial cell loss after cataract surgery. Can J Ophthalmol 2019; 54: 438-444
• 4 Chen MJ, Liu CJ, Cheng CY. et al. Corneal status in primary angle-closure glaucoma with a history of acute attack. J Glaucoma 2012; 21: 12-16
• 5 Prinz J, Walter P, Liu H. et al. The Impact of Aging on the Function of Retinal Ganglion Cells. Klin Monbl Augenheilkd 2024; 241: 162-169
• 6 Pastor SA, Williams R, Hetherington J. et al. Corneal endothelial cell loss following trabeculectomy with mitomycin C. J Glaucoma 1993; 2: 112-113
• 7 Kim MS, Kim KN, Kim CS. Changes in corneal endothelial cell after Ahmed glaucoma valve implantation and trabeculectomy: 1-year follow-up. Korean J Ophthalmol 2016; 30: 416-425
• 8 Saheb H, Ahmed IIK. Micro-invasive glaucoma surgery: current perspectives and future directions. Curr Opin Ophthalmol 2012; 23: 96-104
• 9 Fea AM, Consolandi G, Pignata G. et al. A comparison of endothelial cell loss in combined cataract and MIGS (Hydrus) procedure to phacoemulsification alone: 6-month results. J Ophthalmol 2015; 2015: 769289
• 10 Grover DS, Godfrey DG, Smith O. et al. Gonioscopy-assisted transluminal trabeculotomy, ab interno trabeculotomy: technique report and preliminary results. Ophthalmology 2014; 121: 855-861
• 11 Grover DS, Smith O, Fellman RL. et al. Gonioscopy assisted transluminal trabeculotomy: an ab interno circumferential trabeculotomy for the treatment of primary congenital glaucoma and juvenile open angle glaucoma. Br J Ophthalmol 2015; 99: 1092-1096
• 12 Yu ZY, Wu L, Qu B. Changes in corneal endothelial cell density in patients with primary open-angle glaucoma. World J Clin Cases 2019; 7: 1978
• 13 Edelhauser HF. The resiliency of the corneal endothelium to refractive and intraocular surgery. Cornea 2000; 19: 263-273
• 14 Obuchowska I, Konopińska J. Corneal endothelial cell loss in patients after minimally invasive glaucoma surgery: current perspectives. Clin Ophthalmol 2022; 16: 1589-1600
• 15 Tomaszewski BT, Zalewska R, Mariak Z. Evaluation of the endothelial cell density and the central corneal thickness in pseudoexfoliation syndrome and pseudoexfoliation glaucoma. J Ophthalmol 2014; 2014: 123683
• 16 Thakur SK, Dan A, Singh M. et al. Endothelial cell loss after small incision cataract surgery. Nepal J Ophthalmol 2011; 3: 177-180
• 17 Conrad-Hengerer I, Al Juburi M, Schultz T. et al. Corneal endothelial cell loss and corneal thickness in conventional compared with femtosecond laser–assisted cataract surgery: three-month follow-up. J Cataract Refract Surg 2013; 39: 1307-1313
• 18 Faria BM, Melillo GHL, Daga F. et al. Short-term endothelial cell density changes after gonioscopy-assisted transluminal trabeculotomy. Arq Bras Oftalmol 2021; 85: 344-350
• 19 Olgun A, Karapapak M. Corneal endothelial density loss in patients after gonioscopy-assisted transluminal trabeculotomy. Int Ophthalmol 2024; 44: 330
• 20 Richter GM, Coleman AL. Minimally invasive glaucoma surgery: current status and future prospects. Clin Ophthalmol 2016; 10: 189-206
• 21 Dorairaj S, Balasubramani GK. Corneal Endothelial Cell Changes After Phacoemulsification Combined with Excisional Goniotomy with the Kahook Dual Blade or iStent: A Prospective Fellow-Eye Comparison. Clin Ophthalmol 2020; 14: 4047-4053
• 22 Ventura-Abreu N, García-Feijoo J, Pazos M. et al. Twelve-month results of ab interno trabeculectomy with Kahook Dual Blade: an interventional, randomized, controlled clinical study. Graefes Arch Clin Exp Ophthalmol 2021; 259: 2771-2781
• 23 Ahmed IIK, Sheybani A, De Francesco T. et al. Long-Term Endothelial Safety Profile With iStent Inject in Patients With Open-Angle Glaucoma. Am J Ophthalmol 2023; 252: 17-25
• 24 Ahmed IIK, Rhee DJ, Jones J. et al. HORIZON Investigators. Three-Year Findings of the HORIZON Trial: A Schlemm Canal Microstent for Pressure Reduction in Primary Open-Angle Glaucoma and Cataract. Ophthalmology 2021; 128: 857-865
• 25 Grobshäuser E, Cunha Vaz Martinho A, Gatzioufas Z. et al. Investigation of Endothelial Cell Density after PreserFlo Implantation Compared to Contralateral Eyes without PreserFlo Implantation – A Retrospective Analysis. Klin Monbl Augenheilkd 2025; 242: 392-397
• 26 Konopińska J, Gołaszewska K, Saeed E. Long-term efficacy and safety of ab externo canaloplasty in the Polish Caucasian population with open-angle glaucoma: A 3-year retrospective study. PLoS One 2024; 19: e0312236
• 27 Oddone F, Roberti G, Posarelli C. et al. Endothelial Cell Density After XEN Implant Surgery: Short-term Data From the Italian XEN Glaucoma Treatment Registry (XEN-GTR). J Glaucoma 2021; 30: 559-565
• 28 Cubuk MO, Unsal E. One-year results of gonioscopy-assisted transluminal trabeculotomy: evaluation of prognostic factors. Eur J Ophthalmol 2021; 31: 460-468
• 29 Grover DS, Smith O, Fellman RL. et al. Gonioscopy-assisted transluminal trabeculotomy: an ab interno circumferential trabeculotomy: 24 months follow-up. J Glaucoma 2018; 27: 393-401
• 30 Trinh L, Brignole-Baudouin F, Labbé A. et al. The corneal endothelium in an endotoxin-induced uveitis model: correlation between in vivo confocal microscopy and immunohistochemistry. Mol Vis 2008; 14: 1149
• 31 Agra C, Agra L, Dantas J. et al. Anterior segment optical coherence tomography in acute anterior uveitis. Arq Bras Oftalmol 2014; 77: 1-3
• 32 Cakir I, Altan C, Yalcinkaya G. et al. Evaluation of post phacoemulsification inflammation in eyes with and without pseudoexfoliation syndrome according to phaco parameters via laser flare photometry. Photodiagnosis Photodyn Ther 2022; 38: 102805
• 33 Lass JH, Benetz BA, He J. et al. Corneal Endothelial Cell Loss and Morphometric Changes 5 Years after Phacoemulsification with or without CyPass Micro-Stent. Am J Ophthalmol 2019; 208: 211-218
• 34 US Food and Drug Administration. UPDATE: potential eye damage from alcon CyPass micro-stent used to treat open-angle glaucoma: FDA safety communication. 2018 Accessed December 14, 2018 at: https://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/ucm624283.htm
• 35 Lass JH, Khosrof SA, Laurence JK. et al. A double-masked, randomized, 1-year study comparing the corneal effects of dorzolamide, timolol, and betaxolol. Arch Ophthalmol 1998; 116: 1003-1010
• 36 Janson BJ, Alward WL, Kwon YH. et al. Glaucoma-associated corneal endothelial cell damage: a review. Surv Ophthalmol 2018; 63: 500-506