MyopiaNCT03584555
Comparison of Clinical Outcomes of Small-incision Lenticule Extraction (SMILE) Between Different Cap Thickness.
A study testing SMILE using 120μm cap thickness and SMILE using 140μm cap thickness in people with Myopia, run by Yonsei University at 1 site in South Korea.
Trial summary
In the past two decades, the femtosecond laser (FSL) technology has been introduced in the corneal refractive surgery filed, and brought a remarkable innovation. It can make tissue dissection through photodisruption and plasma cavitation. Read more about this study
- Who is it for?
- Ages 20 to 45 years
- Conditions the study is for
- Myopia
- What is being tested?
- SMILE using 120μm cap thickness and SMILE using 140μm cap thickness
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 70 participants
- Where
- 1 siteSouth Korea
- Study dates
- 18 Mar 2017to 26 Aug 2019
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 20 to 45 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- age of 20 years or older.
- Myopia
- Who is willing to get SMILE surgery
Who cannot join
- severe ocular surface disease
- any corneal disease, cataract, glaucoma, macular disease, or previous history of intraocular or corneal surgery
- Patients with suspicion of keratoconus on corneal topography
Trial locations and contacts
1 site in 1 country.
South Korea1 site
Department of Ophthalmology, Yonsei Univeristy College of Medicine
Seoul, 03722
About this study
In the past two decades, the femtosecond laser (FSL) technology has been introduced in the corneal refractive surgery filed, and brought a remarkable innovation. It can make tissue dissection through photodisruption and plasma cavitation. Initially, the FSL was used predominantly to make a corneal flap when performing laser in situ keratomileusis (LASIK), which is followed by stromal ablation using excimer laser. A new surgical technique called femtosecond lenticule extraction (FLEx) has been developed that uses only FSL to dissect two interfaces to create refractive lenticule and then remove it, which is very similar with LASIK. Small incision lenticule extraction (SMILE) which is the advanced form of all-in-one FSL refractive technique does not make a corneal flap rather make small incision where the separated refractive lenticule is removed through, and the upper part of the corneal tissue is called cap. Since the clinical outcomes of SMILE were firstly published in 2011, SMILE has been widely used for correction of myopia or myopic astigmatism worldwide. SMILE provides excellent visual outcomes and has advantages including a lesser decrease in corneal sensitivity and absence of flap related complications compared to LASIK.
Because corneal ectasia after refractive surgery is the one of most terrifying complication, corneal biomechanics has been drawn interests to many researchers and clinicians. Theoretically, SMILE may preserve corneal biomechanics better than LASIK, because the anterior stroma which is stiffer than the posterior stroma remains intact in SMILE. However, there are some controversies, because previous studies investigating corneal biomechanics have been reported inconsistent outcomes, although SMILE has been reported equal to or better than LASIK. Weakening of corneal biomechanics and iatrogenic corneal ectasia have also been reported after SMILE. In addition, because the tensile strength of cornea gradually decreases as it goes backwards, creating deeper refractive lenticule may result in stronger cornea by preserving more of anterior lamellae of the cornea. But on the contrary, leaving sufficient residual stromal bed has been known to be important in preventing iatrogenic corneal ectasia, hence creating thin cap may be effective and desirable. Although many researches have been investigated the difference in biomechanical response between SMILE and LASIK, there are few studies evaluating the dependence of cap thickness on postoperative biomechanical strength after SMILE. El-Massry et al. reported that the thicker cap thickness showed higher postoperative corneal hysteresis (CH) and corneal resistance factor (CRF) with Ocular Response Analyzer (ORA; Reichert Ophthalmic Instruments, Depew, NY) which may not be optimal for a clear description of the viscosity and elasticity of the cornea,3 ; however, other studies have been presented that there is no significant difference of corneal biomechanics with cap thickness. There is no comparative human study using Corvis ST (Oculus, Wetzlar, Germany) despite presence of the study using Corvis ST in rabbit eyes. Furthermore, no prospective study with large number of subjects has been performed to date.
- Conditions
- Myopia
- Being tested
- SMILE using 120μm cap thickness, SMILE using 140μm cap thickness
- Keywords
- Small incision lenticule extraction, Cap thickness
- Medical subject headings
- Myopia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
SMILE using 120μm cap thicknessProcedure or surgery
The surgery was performed with standardized techniques with triple centration technique using the 500-KHz VisuMax system (Carl Zeiss Meditec AG, Jena, Germany). The superior cap depth was set as 120 or 140 µm, and the length of the side cut was set to 2 mm. Once the anterior (upper) and posterior (lower) planes of the lenticule were defined, the anterior and posterior interfaces were dissected using a micropetala with a blunt circular tip and extracted with midforceps. The integrity of the lenticule was assessed subsequently.
SMILE using 140μm cap thicknessProcedure or surgery
The surgery was performed with standardized techniques with triple centration technique using the 500-KHz VisuMax system (Carl Zeiss Meditec AG, Jena, Germany). The superior cap depth was set as 120 or 140 µm, and the length of the side cut was set to 2 mm. Once the anterior (upper) and posterior (lower) planes of the lenticule were defined, the anterior and posterior interfaces were dissected using a micropetala with a blunt circular tip and extracted with midforceps. The integrity of the lenticule was assessed subsequently.
| Study group | Role | What they receive |
|---|---|---|
| 120 μm group | Active comparator | The subjects underwent SMILE using 120 μm cap. Receives: Procedure: SMILE using 120μm cap thickness |
| 140 μm group | Active comparator | The subjects underwent SMILE using 140 μm cap. Receives: Procedure: SMILE using 140μm cap thickness |
What is being measured
The primary outcome is the main question the study is designed to answer.
Uncorrected Distance Vision Acuity
Uncorrected Distance Vision Acuity in logMAR scale will be compared between the two groups at each time point.
Measured: from preoperative to postoperative 6 months
Corrected Distance vision Acuity
Corrected Distance Vision Acuity in logMAR scale will be compared between the two groups at each time point.
Measured: from preoperative to postoperative 6 months
Secondary outcomes (10)
1.Total higher order aberration at each time point between the two groups.
Total higher order aberrations, spherical aberrations, and coma aberrations are examined using Keratron Scout (Optikon 2000, Rome, Italy). The unit of those is "μm".
1,2. Total higher order aberrations at each time point and change from baseline at each time point will be compared between the two groups.
Measured: from preoperative to postoperative 6 months
2.Total higher order aberration changes from baseline at each postoperative time point between the two groups.
Total higher order aberrations, spherical aberrations, and coma aberrations are examined using Keratron Scout (Optikon 2000, Rome, Italy). The unit of those is "μm".
1,2. Total higher order aberrations at each time point and change from baseline at each time point will be compared between the two groups.
Measured: from preoperative to postoperative 6 months
3.Spherical aberration at each time point between the two groups.
3,4. Spherical aberrations at each time point and change from baseline at each time point will be compared between the two groups.
Measured: from preoperative to postoperative 6 months
4.Spherical aberration changes from baseline at each postoperative time point between the two groups.
3,4. Spherical aberrations at each time point and change from baseline at each time point will be compared between the two groups.
Measured: from preoperative to postoperative 6 months
5.Coma aberration at each time point between the two groups.
5,6. Coma aberrations at each time point and change from baseline at each time point will be compared between the two groups.
Corneal biomechanics including deformation amplitude ratio (DA ratio), and stiffness parameter at first applanation (SP-A1) is examined using Corvis ST (Oculus, Wetzlar, Germany). The unit of SP-A1 is "mm Hg/mm", and DA ratio is unitless.
Measured: from preoperative to postoperative 6 months
6.Coma aberration changes from baseline at each postoperative time point between the two groups.
5,6. Coma aberrations at each time point and change from baseline at each time point will be compared between the two groups.
Corneal biomechanics including deformation amplitude ratio (DA ratio), and stiffness parameter at first applanation (SP-A1) is examined using Corvis ST (Oculus, Wetzlar, Germany). The unit of SP-A1 is "mm Hg/mm", and DA ratio is unitless.
Measured: from preoperative to postoperative 6 months
7.Deformation amplitude ratio (DA ratio) at each time point between the two groups.
7,8 DA ratio at each time point and change from baseline at each time point will be compared between the two groups.
Measured: from preoperative to postoperative 6 months
8.DA ratio changes from baseline at each postoperative time point between the two groups.
7,8 DA ratio at each time point and change from baseline at each time point will be compared between the two groups.
Measured: from preoperative to postoperative 6 months
9.Stiffness parameter at first applanation (SP-A1) at each time point between the two groups.
9,10 SP-A1 at each time point and change from baseline at each time point will be compared between the two groups.
Measured: from preoperative to postoperative 6 months
10.SP-A1 changes from baseline at each postoperative time point between the two groups.
9,10 SP-A1 at each time point and change from baseline at each time point will be compared between the two groups.
Measured: from preoperative to postoperative 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Jul 2018
- Study start18 Mar 2017
- Primary completion26 Aug 2019
- Study completion26 Aug 2019
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (6)Papers the sponsor has linked to this study.
- Other trials for MyopiaStudies of the same condition, open and under way.
- More trials run by Yonsei UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Enrollment period : 24 months after IRB approval Methods: The subjects are randomly divided into two groups. One group underwent SMILE surgery using 120 μm cap thickness, and the other group underwent SMILE surgery using 140 μm cap thickness. Before surgery, all patients underwent a detailed ophthalmological examination that included evaluation of logarithm of the minimum angle of resolution (logMAR) uncorrected-distance visual acuity (UDVA) and CDVA, manifest refraction, slit-lamp examination (Haag-Streit, Köniz, Switzerland), keratometry, and Scheimpflug-based corneal topography (Pentacam HR, Oculus). Dynamic corneal response (DCR) parameters were examined using Corvis ST. Corneal wavefront aberrations were measured using Keratron Scout (Optikon 2000, Rome, Italy). All examinations were repeated at 1, 3, and 6 months after surgery.
- Masking
- None (open label)
- Enrolment
- 70 participants (actual)
Sponsor and investigators
- Lead sponsor
- Yonsei University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03584555
- Sponsor's protocol ID
- 4-2017-0063
- Status last verified
- Oct 2020
- First submitted
- 19 Jun 2018
- Last updated
- 19 Oct 2020
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Damgaard IB, Ivarsen A, Hjortdal J. Refractive Correction and Biomechanical Strength Following SMILE With a 110- or 160-mum Cap Thickness, Evaluated Ex Vivo by Inflation Test. Invest Ophthalmol Vis Sci. 2018 Apr 1;59(5):1836-1843. doi: 10.1167/iovs.17-23675.
PubMed 29610851Fernandez J, Rodriguez-Vallejo M, Martinez J, Tauste A, Pinero DP. Corneal biomechanics after laser refractive surgery: Unmasking differences between techniques. J Cataract Refract Surg. 2018 Mar;44(3):390-398. doi: 10.1016/j.jcrs.2017.10.054. Epub 2018 Mar 31.
PubMed 29615281Weng S, Liu M, Yang X, Liu F, Zhou Y, Lin H, Liu Q. Evaluation of Human Corneal Lenticule Quality After SMILE With Different Cap Thicknesses Using Scanning Electron Microscopy. Cornea. 2018 Jan;37(1):59-65. doi: 10.1097/ICO.0000000000001404.
PubMed 29053560He M, Wang W, Ding H, Zhong X. Comparison of Two Cap Thickness in Small Incision Lenticule Extraction: 100mum versus 160mum. PLoS One. 2016 Sep 21;11(9):e0163259. doi: 10.1371/journal.pone.0163259. eCollection 2016.
PubMed 27655417Liu M, Zhou Y, Wu X, Ye T, Liu Q. Comparison of 120- and 140-mum SMILE Cap Thickness Results in Eyes With Thick Corneas. Cornea. 2016 Oct;35(10):1308-14. doi: 10.1097/ICO.0000000000000924.
PubMed 27467038El-Massry AA, Goweida MB, Shama Ael-S, Elkhawaga MH, Abdalla MF. Contralateral Eye Comparison Between Femtosecond Small Incision Intrastromal Lenticule Extraction at Depths of 100 and 160 mum. Cornea. 2015 Oct;34(10):1272-5. doi: 10.1097/ICO.0000000000000571.
PubMed 26266430
Study at a glance
From the registry record, last updated by the sponsor on 19 Oct 2020. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison of Clinical Outcomes of Small-incision Lenticule Extraction (SMILE) Between Different Cap Thickness.
- ClinicalTrials.gov ID
- NCT03584555
- Acronym / sponsor ID
- 4-2017-0063
- Conditions
- Myopia
- Keywords
- Small incision lenticule extraction, Cap thickness
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 70 participants (actual)
- Lead sponsor
- Yonsei UniversityUniversity, hospital or other
- Study start
- 18 Mar 2017 (actual)
- Primary completion
- 26 Aug 2019 (actual)
- Study completion
- 26 Aug 2019 (actual)
- First posted
- 12 Jul 2018 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
In the past two decades, the femtosecond laser (FSL) technology has been introduced in the corneal refractive surgery filed, and brought a remarkable innovation. It can make tissue dissection through photodisruption and plasma cavitation. Initially, the FSL was used predominantly to make a corneal flap when performing laser in situ keratomileusis (LASIK), which is followed by stromal ablation using excimer laser. A new surgical technique called femtosecond lenticule extraction (FLEx) has been developed that uses only FSL to dissect two interfaces to create refractive lenticule and then remove it, which is very similar with LASIK. Small incision lenticule extraction (SMILE) which is the advanced form of all-in-one FSL refractive technique does not make a corneal flap rather make small incision where the separated refractive lenticule is removed through, and the upper part of the corneal tissue is called cap. Since the clinical outcomes of SMILE were firstly published in 2011, SMILE has been widely used for correction of myopia or myopic astigmatism worldwide. SMILE provides excellent visual outcomes and has advantages including a lesser decrease in corneal sensitivity and absence of flap related complications compared to LASIK.
Because corneal ectasia after refractive surgery is the one of most terrifying complication, corneal biomechanics has been drawn interests to many researchers and clinicians. Theoretically, SMILE may preserve corneal biomechanics better than LASIK, because the anterior stroma which is stiffer than the posterior stroma remains intact in SMILE. However, there are some controversies, because previous studies investigating corneal biomechanics have been reported inconsistent outcomes, although SMILE has been reported equal to or better than LASIK. Weakening of corneal biomechanics and iatrogenic corneal ectasia have also been reported after SMILE. In addition, because the tensile strength of cornea gradually decreases as it goes backwards, creating deeper refractive lenticule may result in stronger cornea by preserving more of anterior lamellae of the cornea. But on the contrary, leaving sufficient residual stromal bed has been known to be important in preventing iatrogenic corneal ectasia, hence creating thin cap may be effective and desirable. Although many researches have been investigated the difference in biomechanical response between SMILE and LASIK, there are few studies evaluating the dependence of cap thickness on postoperative biomechanical strength after SMILE. El-Massry et al. reported that the thicker cap thickness showed higher postoperative corneal hysteresis (CH) and corneal resistance factor (CRF) with Ocular Response Analyzer (ORA; Reichert Ophthalmic Instruments, Depew, NY) which may not be optimal for a clear description of the viscosity and elasticity of the cornea,3 ; however, other studies have been presented that there is no significant difference of corneal biomechanics with cap thickness. There is no comparative human study using Corvis ST (Oculus, Wetzlar, Germany) despite presence of the study using Corvis ST in rabbit eyes. Furthermore, no prospective study with large number of subjects has been performed to date.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Enrollment period : 24 months after IRB approval Methods: The subjects are randomly divided into two groups. One group underwent SMILE surgery using 120 μm cap thickness, and the other group underwent SMILE surgery using 140 μm cap thickness. Before surgery, all patients underwent a detailed ophthalmological examination that included evaluation of logarithm of the minimum angle of resolution (logMAR) uncorrected-distance visual acuity (UDVA) and CDVA, manifest refraction, slit-lamp examination (Haag-Streit, Köniz, Switzerland), keratometry, and Scheimpflug-based corneal topography (Pentacam HR, Oculus). Dynamic corneal response (DCR) parameters were examined using Corvis ST. Corneal wavefront aberrations were measured using Keratron Scout (Optikon 2000, Rome, Italy). All examinations were repeated at 1, 3, and 6 months after surgery.
| Arm | Type | Receives |
|---|---|---|
| 120 μm group | Active comparator | Procedure: SMILE using 120μm cap thicknessThe subjects underwent SMILE using 120 μm cap. |
| 140 μm group | Active comparator | Procedure: SMILE using 140μm cap thicknessThe subjects underwent SMILE using 140 μm cap. |
Who may qualify
- Ages
- 20 to 45 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- age of 20 years or older.
- Myopia
- Who is willing to get SMILE surgery
Key exclusion criteria (3 listed)
- severe ocular surface disease
- any corneal disease, cataract, glaucoma, macular disease, or previous history of intraocular or corneal surgery
- Patients with suspicion of keratoconus on corneal topography
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| SMILE using 120μm cap thicknessThe surgery was performed with standardized techniques with triple centration technique using the 500-KHz VisuMax system (Carl Zeiss Meditec AG, Jena, Germany). The superior cap depth was set as 120 or 140 µm, and the length of the side cut was set to 2 mm. Once the anterior (upper) and posterior (lower) planes of the lenticule were defined, the anterior and posterior interfaces were dissected using a micropetala with a blunt circular tip and extracted with midforceps. The integrity of the lenticule was assessed subsequently. | Procedure or surgery | 120 μm group |
| SMILE using 140μm cap thicknessThe surgery was performed with standardized techniques with triple centration technique using the 500-KHz VisuMax system (Carl Zeiss Meditec AG, Jena, Germany). The superior cap depth was set as 120 or 140 µm, and the length of the side cut was set to 2 mm. Once the anterior (upper) and posterior (lower) planes of the lenticule were defined, the anterior and posterior interfaces were dissected using a micropetala with a blunt circular tip and extracted with midforceps. The integrity of the lenticule was assessed subsequently. | Procedure or surgery | 140 μm group |
Primary outcome
Uncorrected Distance Vision Acuity
Time frame: from preoperative to postoperative 6 months
Uncorrected Distance Vision Acuity in logMAR scale will be compared between the two groups at each time point.
Corrected Distance vision Acuity
Time frame: from preoperative to postoperative 6 months
Corrected Distance Vision Acuity in logMAR scale will be compared between the two groups at each time point.
10 secondary outcomes
1.Total higher order aberration at each time point between the two groups.
Time frame: from preoperative to postoperative 6 months
2.Total higher order aberration changes from baseline at each postoperative time point between the two groups.
Time frame: from preoperative to postoperative 6 months
3.Spherical aberration at each time point between the two groups.
Time frame: from preoperative to postoperative 6 months
4.Spherical aberration changes from baseline at each postoperative time point between the two groups.
Time frame: from preoperative to postoperative 6 months
5.Coma aberration at each time point between the two groups.
Time frame: from preoperative to postoperative 6 months
6.Coma aberration changes from baseline at each postoperative time point between the two groups.
Time frame: from preoperative to postoperative 6 months
7.Deformation amplitude ratio (DA ratio) at each time point between the two groups.
Time frame: from preoperative to postoperative 6 months
8.DA ratio changes from baseline at each postoperative time point between the two groups.
Time frame: from preoperative to postoperative 6 months
9.Stiffness parameter at first applanation (SP-A1) at each time point between the two groups.
Time frame: from preoperative to postoperative 6 months
10.SP-A1 changes from baseline at each postoperative time point between the two groups.
Time frame: from preoperative to postoperative 6 months
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 19 Oct 2020.
- Background: PubMed 29610851Damgaard IB, Ivarsen A, Hjortdal J. Refractive Correction and Biomechanical Strength Following SMILE With a 110- or 160-mum Cap Thickness, Evaluated Ex Vivo by Inflation Test. Invest Ophthalmol Vis Sci. 2018 Apr 1;59(5):1836-1843. doi: 10.1167/iovs.17-23675.
- Background: PubMed 29615281Fernandez J, Rodriguez-Vallejo M, Martinez J, Tauste A, Pinero DP. Corneal biomechanics after laser refractive surgery: Unmasking differences between techniques. J Cataract Refract Surg. 2018 Mar;44(3):390-398. doi: 10.1016/j.jcrs.2017.10.054. Epub 2018 Mar 31.
- Background: PubMed 29053560Weng S, Liu M, Yang X, Liu F, Zhou Y, Lin H, Liu Q. Evaluation of Human Corneal Lenticule Quality After SMILE With Different Cap Thicknesses Using Scanning Electron Microscopy. Cornea. 2018 Jan;37(1):59-65. doi: 10.1097/ICO.0000000000001404.
- Background: PubMed 27655417He M, Wang W, Ding H, Zhong X. Comparison of Two Cap Thickness in Small Incision Lenticule Extraction: 100mum versus 160mum. PLoS One. 2016 Sep 21;11(9):e0163259. doi: 10.1371/journal.pone.0163259. eCollection 2016.
- Background: PubMed 27467038Liu M, Zhou Y, Wu X, Ye T, Liu Q. Comparison of 120- and 140-mum SMILE Cap Thickness Results in Eyes With Thick Corneas. Cornea. 2016 Oct;35(10):1308-14. doi: 10.1097/ICO.0000000000000924.
- Background: PubMed 26266430El-Massry AA, Goweida MB, Shama Ael-S, Elkhawaga MH, Abdalla MF. Contralateral Eye Comparison Between Femtosecond Small Incision Intrastromal Lenticule Extraction at Depths of 100 and 160 mum. Cornea. 2015 Oct;34(10):1272-5. doi: 10.1097/ICO.0000000000000571.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing SMILE using 120μm cap thickness and SMILE using 140μm cap thickness in people with Myopia, run by Yonsei University at 1 site in South Korea.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 19 Oct 2020. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in South Korea. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Uncorrected Distance Vision Acuity (time frame: from preoperative to postoperative 6 months). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03584555, which also lists 6 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 19 Oct 2020.