The Impact of Surgical Procedures on Postoperative Outcomes in Cataract Phacoemulsification and Analysis of Related Factors

The goal of this observational study is to evaluate the location of phacoemulsification tip measured by intraoperative OCT during cataract surgeries and its impact on early postoperative changes of cornea and visual acuity. The main question it aims to answer is:

In patients with age-related cataracts undergoing phacoemulsification, does the location (supracapsular, iris-lens diaphragm, or endocapsular) of the phaco tip affect postoperative corneal changes and visual acuity at early postoperative stage? Eyes having phacoemulsification for cataracts will receive intraoperative OCT imaging to evaluate the location of the phaco tip during surgery, and corneal changes and visual acuity will be measured postoperatively.

Study Overview

• Status: Recruiting
• Conditions: Age-related Cataract
• Intervention / Treatment: Procedure: cataract surgery

• Study Type: Observational
• Enrollment (Estimated): 300

Contacts and Locations

Study Locations

• China
  • Guangdong
    • Guangzhou, Guangdong, China, 510000
      • Recruiting
      • Zhongshan Ophthalmic Center, Sun Yat-sen University
      • Contact: Zitian Liu, MD, PhD; Phone Number: +8618319249014; Email: liuzt25@mail.sysu.edu.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Patients who are planning to receive phacoemulsification combined with intraocular lens implantation for unilateral/bilateral age-related cataract

Description

Inclusion Criteria:

• Age ≥ 50 years and ≤ 90 years
• Diagnosis of unilateral/bilateral age-related cataract
• Nuclear grade ≥2 in LOCSIII classification
• Scheduled for cataract phacoemulsification combined with intraocular lens implantation
• Pupil size ≥6mm after dilation
• Corneal endothelial cell count ≥1500 cells/mm²

Exclusion Criteria:

• Diagnosis of severe systemic disease (e.g., severe hypertension or Alzheimer's disease)
• History of ocular trauma or surgery
• Presence of other ocular diseases (such as glaucoma, diabetic retinopathy, or high myopia)
• Other ocular factors that may complicate the surgery (such as small pupil, shallow anterior chamber)

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Phacoemulsification	Procedure: cataract surgery; Cataract phacoemulsification combined with intraocular lens implantation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in corneal thickness	Corneal thickness measured by corneal endothelial specular microscope	postoperative day 1, week 1, and month 1

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in corneal endothelial cell density	Measured using corneal endothelial specular microscope	1 day, 1 week, and 1 month postoperatively
Best-corrected visual acuity	Measured using ETDRS visual acuity protocol with ETDRS visual acuity chart by a masked examiner	1 day, 1 week, and 1 month postoperatively
Intraoperative and postoperative complications	Monitored by cataract surgeons using intraoperative OCT and postoperative slit-lamp examination. Complications include Descemet membrane detachment, posterior capsule rupture, incision leakage, and etc.	Intraoperative, 1 day, 1 week, and 1 month postoperatively

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Position of Phacoemulsification	Swept-source intraoperative optical coherence tomography (SS-iOCT) will be used for real-time measurements throughout the surgery. The imaging depth will be set to 12 mm to ensure full visualization from the anterior corneal surface to the posterior lens surface. During phacoemulsification, a five-line scanning pattern will be applied, with the central line aligned with the phaco tip. The iris-lens diaphragm plane will be used as the reference standard on iOCT images. The phaco tip will be considered to be in the supracapsular space when positioned above this plane, at the iris-lens diaphragm plane when exactly at the plane, and in the endocapsular space when positioned below the plane. The duration of phaco tip manipulation in the supracapsular space, at the iris-lens diaphragm plane, and in the endocapsular space will be recorded throughout the phacoemulsification process.	During phacoemulsification

Collaborators and Investigators

• Sponsor: Zhongshan Ophthalmic Center, Sun Yat-sen University

Publications and helpful links

General Publications

• Liu Y, Zeng M, Liu X, Luo L, Yuan Z, Xia Y, Zeng Y. Torsional mode versus conventional ultrasound mode phacoemulsification: randomized comparative clinical study. J Cataract Refract Surg. 2007 Feb;33(2):287-92. doi: 10.1016/j.jcrs.2006.10.044.
• Lundberg B, Jonsson M, Behndig A. Postoperative corneal swelling correlates strongly to corneal endothelial cell loss after phacoemulsification cataract surgery. Am J Ophthalmol. 2005 Jun;139(6):1035-41. doi: 10.1016/j.ajo.2004.12.080.
• Liu Z, Lin H, Jin L, Qu B, Liu J, Zheng Y, He M, Luo L, Liu Y. Swab Pressing vs Stromal Hydration to Prevent Incision Leakage and Transient Collapse of Anterior Chamber in Phacoemulsification: A Randomized Clinical Trial. JAMA Ophthalmol. 2023 Jun 1;141(6):574-581. doi: 10.1001/jamaophthalmol.2023.1491.
• Dewan T, Malik PK, Kumari R. Comparison of effective phacoemulsification time and corneal endothelial cell loss using 2 ultrasound frequencies. J Cataract Refract Surg. 2019 Sep;45(9):1285-1293. doi: 10.1016/j.jcrs.2019.04.015. Epub 2019 Jul 29.
• Dewan T, Malik PK, Tomar P. Comparison of effective phacoemulsification time and corneal endothelial cell loss using three different ultrasound frequencies: A randomized controlled trial. Indian J Ophthalmol. 2022 Apr;70(4):1180-1185. doi: 10.4103/ijo.IJO_2163_21.
• Liu Y, Jiang Y, Wu M, Liu Y, Zhang T. Bimanual microincision phacoemulsification in treating hard cataracts using different power modes. Clin Exp Ophthalmol. 2008 Jul;36(5):426-30.

Study record dates

Study Major Dates

• Study Start (Actual): April 20, 2026
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): June 30, 2027

Study Registration Dates

• First Submitted: April 15, 2026
• First Submitted That Met QC Criteria: April 19, 2026
• First Posted (Actual): April 24, 2026

Study Record Updates

• Last Update Posted (Actual): June 3, 2026
• Last Update Submitted That Met QC Criteria: June 1, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Surgical Procedures, Operative; Ophthalmologic Surgical Procedures; Refractive Surgical Procedures; Cataract Extraction
• Other Study ID Numbers: IIT2025172

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No