Total Corneal Astigmatism Prevalence in Cataract Patients

NCT06148857 | Unknown

• 1 other identifier: BLB2
• Study Type: observational
• Target: 11,000
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to report the prevalence data for total corneal astigmatism (TCA) in cataract surgery candidates.

Conditions

Cataract

Keywords

cataract; astigmatism; prevalence

Outcome Measures

Primary Outcomes (3)

• total keratometric astigmatism

  Total keratometry is calculated based on the anterior and posterior corneal surface radius and CCT using the thick lens formula with the actual indices of refractions for air (1.000), cornea (1.376), and aqueous (1.336) by IOLMaster 700. Total keratometric astigmatism is taken as the TCA measured by IOLMaster 700.

  At Enrollment

• Abulafia-Koch formula total corneal astigmatism

  The AK formula, described by Abulafia et al, is a regression formula that calculates an estimated TCA using K astigmatism.

  At Enrollment

• Barrett toric calculator total corneal astigmatism

  The Barrett toric calculator uses an unpublished mathematical prediction method of TCA based on anterior corneal measurements. AL, ACD, LT, WTW, and K data by IOLMaster 700 were input into the Barrett toric calculator. The target refraction, incision surgically induced astigmatism (SIA), and incision location were all set as 0. The output net astigmatism was recorded as TCA predicted by the Barrett toric calculator.

  At Enrollment

Interventions

IOLMaster 700 DIAGNOSTIC_TEST

The IOLMaster 700, one of the most commonly used optical biometers for IOL power calculation, measures the anterior corneal surface radius using a telecentric keratometry. Additionally, it employs swept-source optical coherence tomography (SS-OCT) technology to simultaneously measures the posterior cornea surface radius and central corneal thickness (CCT). The AK formula, described by Abulafia et al., is a regression formula that calculates an estimated TCA using K astigmatism. The Barrett toric calculator uses an unpublished mathematical prediction method of TCA based on anterior corneal measurements.

Also known as: the Abulafia-Koch formula, the Barrett toric calculator

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

All the patients who underwent cataract surgery in the Department of Ophthalmology, Peking University Third Hospital from January 2019 to May 2023.

You may qualify if:

• Patients who underwent cataract surgery in the Department of Ophthalmology, Peking University Third Hospital from January 2019 to May 2023.

You may not qualify if:

• Incomplete biometric data .

Sponsors & Collaborators

• Peking University Third Hospital: lead

Study Sites (1)

Peking University Third Hospital

Beijing, Beijing Municipality, 100191, China

Location

MeSH Terms

Conditions

Cataract; Astigmatism

Condition Hierarchy (Ancestors)

Lens Diseases; Eye Diseases; Refractive Errors

Study Officials

• Hong Qi, Dr.

  Peking University Third Hospital

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Hong Qi, Dr.

CONTACT

+8613901066889; doctorgihong@163.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: November 20, 2023
• First Posted: November 28, 2023
• Study Start: November 1, 2023
• Primary Completion: November 1, 2023
• Study Completion: December 1, 2023
• Last Updated: November 28, 2023

Record last verified: 2023-11

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)