Plain English Summary
Background and study aims
Cataracts are a disease in which the lens of the eye becomes cloudy. This can be caused by age. Astigmatism is a condition where vision may be blurred as a result of an error of the lens. Patients with both cataracts and astigmatism often undergo surgery where an ordinary intraocular lens is inserted. This fixes cataracts, but does not correct astigmatism and therefore patients may still have poor vision.
To correct both astigmatism and cataracts, a type of lens called a toric intraocular lens can be inserted. It is important to insert the toric intraocular lens in the correct axis (the position of the astigmatism) in order to effectively correct the astigmatism.
There are two methods of indicating, or marking, the axis of lens implantation - either using a machine-based method, or manually by the surgeon performing the operation. We aimed to determine which of these methods is more effective.
Who can participate?
Adults with cataracts and corneal astigmatism
What does the study involve?
Participants will undergo lens implantation cataract surgery, and will be randomly allocated to receive this surgery either using a machine or from a surgeon and will receive follow up tests 1 day, 1 month and 2 months after the surgery. Additionally, participants will be tested for uncorrected and best corrected visual acuity before and 1 day, 1 month and 2 months after the surgery.
What are the possible benefits and risks of participating?
The benefit to participants of taking part is that their cataracts will be removed and their astigmatism will be corrected. A possible risk of taking part is complications from cataract surgery, such as infection.
Where is the study run from?
St Mary's Hospital, Seoul, South Korea
When is the study starting and how long is it expected to run for?
February 2014 to April 2018
Who is funding the study?
1. Korean Health Technology R&D Project (South Korea)
2. Ministry for Health & Welfare, Republic of Korea (South Korea)
3. National Research Foundation of Korea (NRF) (South Korea)
Who is the main contact?
Dr Rowoon Yi
Accuracy of Toric Intraocular Lens implantation using Automated Vs Manual Marking
The SensoMotoric Instruments (SMI) is more accurate than manual marking for Toric IOL implantation during cataract surgery.
Institutional review board of Bucheon St. Mary’s Hospital, 02/01/2014, HC14RISI0077
Prospective interventional randomised controlled trial
Primary study design
Secondary study design
Randomised controlled trial
Patient information sheet
Not available in web format, please use contact details to request a participant information sheet
Cataracts with corneal astigmatism
Participants will be randomised to either SMI group or manual group in a 1:1 allocation using individual-level blocked randomisation stratified by sex (male, female) and age. The randomisation sequence will be computer-generated by the trial statistician and programmed by the data manager.
The SMI group will undergo toric intraocular lens implantation using SMI (SensorMotoric Instruments) marking, whereas the manual group will undergo toric intraocular lens implantation using manual marking (done by a surgeon).
Before and after lens implantation, participants were tested for uncorrected visual acuity, best corrected visual acuity and corneal topography.
Primary outcome measure
Toric intraocular axis, measured using a refractometer 1 day, 1 month and 2 months post-operation
Secondary outcome measures
The following are measured by a physician using the logMAR method 1 day, 1 month and 2 months post-operation:
1. Uncorrected visual acuity
2. Best corrected visual acuity
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
2. Corneal astigmatism > 1.5 diopters
3. Aged over 20
Target number of participants
Participant exclusion criteria
2. Retinal disease
3. Irregular astigmatism
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
Seoul St. Mary’s Hospital
Department of Ophthalmology, The Catholic University of Korea, Seoul St. Mary’s Hospital, #222 Banpo-daero, Seocho-gu, Seoul 137-701, Korea
Ministry for Health & Welfare, Republic of Korea
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
Plan to publish in BMC Ophthalmology in 2018
IPD sharing statement:
The datasets generated during and/or analysed during the current study are/will be available upon request from Dr Rowoon Yi (firstname.lastname@example.org). The data available will be individual participant data that underlies the results reported after deidentification (text, tables, figures and appendices), along with the study protocol. Data will be available from 9 months after until 36 months after article publication and will be shared with investigators whose proposed use of the data has been approved by an independent review committee. Data provided may be used for individual participant meta-analysis. Proposals should be directed to email@example.com(Rowoon Yi, clinical fellow) to gain access and data requestors will need to sign a data access agreement.
Intention to publish date
Participant level data
Available on request
Basic results (scientific)
The steep axis may be measured differently using SensoMotoric Instruments(SMI) and manual marking. The SMI is more accurate than manual marking for Toric IOL implantation during cataract surgery.