Contact Lens ComplicationSCL SMILENCT07001306
Long-term Effects of SCL-wearing on Corneal Neuromediators and Postoperative Rehabilitation After SMILE
An observational study of Contact Lens Complication and Small Incision Lenticule Extraction, run by yuhao shao at 1 site in China.
Trial summary
To investigate the effects of neuromediators in corneal stromal lenticules from patients with long-term soft contact lens (SCL) wear on corneal nerve regeneration and visual quality recovery following small incision lenticule extraction (SMILE). Read more about this study
- Who is it for?
- Ages 18 to 45 yearsHealthy volunteers can take part
- Conditions the study is for
- Contact Lens Complication, Small Incision Lenticule Extraction
- How many people
- 90 participants
- Where
- 1 siteChina
- Study dates
- 1 Jun 2023to 20 May 2025
- Phase
- Observational
- 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 18 to 45 years
- All sexes
- Healthy volunteers accepted
- Adult
Study population: patients with myopia who underwent SMILE surgery at Shanghai Tenth People's Hospital in Shanghai, China, from June 2023 to the present.
Who may be able to join
- age ≥ 18 years with stable refraction for at least two years;
- corrected distance visual acuity of 20/20 or better;
- no history of using rigid gas permeable lenses or orthokeratology (OK) lenses prior to examination
Who cannot join
- a history of moderate to severe dry eye as well as any ocular or systemic disease that would contraindicate laser refractive surgery.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: A Prospective Clinical Study of Long-term Effects of SCL-wearing on Corneal Neuromediators and Postoperative Rehabilitation After SMILE
To investigate the effects of neuromediators in corneal stromal lenticules from patients with long-term soft contact lens (SCL) wear on corneal nerve regeneration and visual quality recovery following small incision lenticule extraction (SMILE).
Read the detailed description
he prospective cohort study recruited 90 patients who underwent SMILE between June 2023 and June 2024. 90 eyes were categorized into three groups according to the duration of wearing SCL: the > 10 years group (25 eyes), the ≤ 10 years group (35 eyes), and the non-wear (NW) group (30 eyes). Pre- and post-operative assessments at 1, 3 and 6 months included corneal higher-order aberrations (HOAs), corneal optical density, tear film breakup time (BUT), corneal fluorescein staining, subepithelial corneal nerve fiber parameters, Ocular Surface Disease Index (OSDI), Quality of Vision (QOV) scores, and contrast sensitivity function (CSF). nerve growth factor (NGF), insulin-like growth factor binding protein-1 (IGFBP-1), mesencephalic astrocyte-derived neurotrophic factor (MANF), calcitonin gene-related peptide (CGRP) and substance P (SP) in stromal lenticules were quantified using ELISA. Multiple linear regression analysis was employed to evaluate the associations between SCL wear duration, mediator levels, and postoperative outcomes.
- Keywords
- small incision lenticule extraction, neuromediators, visual quality, corneal nerve regeneration, soft contact lens
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| SCLs >10 years | myopia patients who wear SCL more than 10 years before Small Incision Lenticule Extraction | |
| SCLs ≤10 years | myopia patients who wear SCL for 10 years or less before Small Incision Lenticule Extraction | |
| NW | myopia patients who have not worn SCLs before Small Incision Lenticule Extraction |
What is being measured
The primary outcome is the main question the study is designed to answer.
Quality of Vision (QOV) scores
It consists of 10 items related to visual symptoms, including glare, halo, radiating light, foggy vision, blurred vision, visual distortion, diplopia, visual fluctuation, difficulty in focusing and difficulty in depth perception. Each item consists of three dimensions: frequency, severity and degree of distress. Therefore, this questionnaire contains a total of 30 questions. The answers to the above three dimensions respectively include four options, namely frequency: never, occasionally, often, and frequently; Severity: None, mild, moderate, severe; Degree of distress: None, a little, some, very much. The corresponding scores for the four options are 0, 1, 2, and 3 respectively. The higher the score, the worse the visual quality
Measured: baseline, 1 month, 3months, 6months
contrast sensitivity function
Under sufficient correction conditions, dark adaptation lasted for 10 minutes. Using the CSV-1000 contrast sensitivity tester at a distance of 3 meters, under the conditions of bright vision (85 cd/m ²), bright glare (135 lx), dark vision (3 cd/m ²), and dark glare (28 lx) respectively, Test the highest CS level that can be distinguished at 3, 6, 12 and 18 c/d spatial frequencies one by one. At each spatial frequency, the examinee needs to point out the bar grid sight in the upper and lower two circular sight targets and report the direction of the bar grid. After the result is correct, gradually reduce the bar grid contrast until the examinee can no longer recognize it. The inverse of the lowest recognizable contrast at this time is the contrast sensitivity. Record in logarithmic units according to the grade value conversion table.
Measured: baseline, 1moth, 3 moths, 6 months
Corneal subepithelial nerve fibers
In this study, the ACCMetrics V.2 software developed by the University of Manchester in the UK for the HRT confocal microscope of Heidelberg Company was used to conduct automatic quantitative analysis and data recording on three nerve fiber images at different positions selected in a single shoot. The parameters analyzed include corneal nerve fiber density (CNFD sterand/mm 2) and corneal nerve fiber length( CNFL, mm/mm 2), corneal nerve fiber area (CNFA mm2/mm 2), corneal nerve fiber width (CNFW mm ), etc. Each inspection is carried out by the same inspector to reduce subjective errors.
Measured: baseline, 1moth, 3 moths, 6 months
Corneal stromal lenticule Neuromediators
Corneal neuromediators, including NGF(pg/mL), CGRP(pg/mL), SP(pg/mL), IGFBP-1(ng/mL), and MANF(pg/mL), which play pivotal roles in maintaining normal physiological functions of the cornea.
Measured: baseline
OSDI Questionnaire
The impact of dry eye on the subjective symptoms of patients was evaluated from three dimensions: ocular symptoms, visual function, and environmental stimuli. There were a total of 12 items. Each symptom was divided into 5 levels according to the degree and occurrence frequency: 0 was considered as none. 1 point occurs sometimes; 2 minutes occurs approximately half of the time; 3 points occur frequently; 4 points occur continuously. The final OSDI score = the total of all scores ×100/ (the total number of assessment questions ×4), with a total score ranging from 0 to 100.
Measured: baseline, 1moth, 3 moths, 6 months
Secondary outcomes (3)
Tear film stability
Including corneal fluorescein staining score and tear film break-up time examination.
Corneal fluorescein staining score The corneal fluorescein staining was observed in different regions under a cobalt blue filter and scored. The cornea was divided into three regions: upper, middle and lower. Scores were given based on the fluorescein staining of the corneal epithelium in each region. No staining was scored as 0 points, 1 point for 1 to 30 staining points, 2 points for more than 30 staining points and no fusion of the staining points, and 3 points for the presence of corneal patellar staining fusion, filamentous substances and ulcers, etc. The total score is 9 points.
Tear film break-up time Instruct the patients to look straight ahead, observe with a slit lamp and cobalt blue filter, and measure the time when dry spots first appear on the cornea after one involuntary blinking movement with a stopwatch. Each patient is measured three times, and the average of the three measurements i
Measured: baseline, 1moth, 3 moths, 6 months
Corneal Aberration
Preoperative corneal aberration measurements were performed using a Scheimpflug tomography system (Pentacam; Oculus GmbH, Wetzlar, Germany). Images of the highest quality (designated as OK) were selected for analysis. The coefficients for a standardized diameter of 8 ?mm were examined, followed by an assessment of the clinical significance of total higher-order aberrations (HOA, mm), spherical aberration (Z4, 0, mm), horizontal coma (Z3, 1, mm), vertical coma (Z3, -1, mm), horizontal trefoil (Z3, 3, mm), and oblique trefoil (Z3, -3, mm) in relation to visual quality.
Measured: baseline, 1moth, 3 moths, 6 months
Corneal Densitometry
The Pentacam HR was used to collect data on corneal densitometry values, which were expressed in grayscale units (GSUs), playing a crucial role in quantifying corneal clarity by monitoring transient haze-like reactions. The cornea was divided into four annular zones (0-2 mm, 2-6 mm, 6-10 mm, and 10-12 mm), each exhibiting distinct corneal densitometry values. Based on the anatomical layers of the cornea at different depths, it consists of four layers: a superficial anterior layer of 120 μm, a posterior layer located within the innermost part of the cornea measuring 60 μm; central layers calculated by subtracting thickness of the anterior and posterior layers from the total layer thickness; and a total layer. Corneal densitometry values were measured in the 0-2 mm and 2-6 mm to correspond to the corneal optical zone diameter of SMILE.
Measured: baseline, 1moth, 3 moths, 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted3 Jun 2025
- Study start1 Jun 2023
- Primary completion30 Jun 2024
- Study completion20 May 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Contact Lens ComplicationStudies of the same condition, open and under way.
- 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
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 90 participants (actual)
Sponsor and investigators
- Lead sponsor
- yuhao shao
- Sponsor type
- University, hospital or other
- Collaborators
- Shanghai 10th People's Hospital
- Responsible party
- Sponsor-investigator, yuhao shao, Tongji University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07001306
- Sponsor's protocol ID
- SCL on SMILE visual quality
- Other IDs
- 202240131, YJXYS-B-009, YNCR2C004, 2023SQ03
- Acronym
- SCL SMILE
- Status last verified
- Jul 2025
- First submitted
- 22 May 2025
- Last updated
- 20 Jul 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 20 Jul 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Prospective Clinical Study of Long-term Effects of SCL-wearing on Corneal Neuromediators and Postoperative Rehabilitation After SMILE
- ClinicalTrials.gov ID
- NCT07001306
- Acronym / sponsor ID
- SCL SMILE / SCL on SMILE visual quality
- Keywords
- small incision lenticule extraction, neuromediators, visual quality, corneal nerve regeneration, soft contact lens
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 90 participants (actual)
- Lead sponsor
- yuhao shaoUniversity, hospital or other
- Collaborators
- Shanghai 10th People's Hospital
- Study start
- 1 Jun 2023 (actual)
- Primary completion
- 30 Jun 2024 (actual)
- Study completion
- 20 May 2025 (actual)
- First posted
- 3 Jun 2025 (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.
To investigate the effects of neuromediators in corneal stromal lenticules from patients with long-term soft contact lens (SCL) wear on corneal nerve regeneration and visual quality recovery following small incision lenticule extraction (SMILE).
Detailed description
he prospective cohort study recruited 90 patients who underwent SMILE between June 2023 and June 2024. 90 eyes were categorized into three groups according to the duration of wearing SCL: the > 10 years group (25 eyes), the ≤ 10 years group (35 eyes), and the non-wear (NW) group (30 eyes). Pre- and post-operative assessments at 1, 3 and 6 months included corneal higher-order aberrations (HOAs), corneal optical density, tear film breakup time (BUT), corneal fluorescein staining, subepithelial corneal nerve fiber parameters, Ocular Surface Disease Index (OSDI), Quality of Vision (QOV) scores, and contrast sensitivity function (CSF). nerve growth factor (NGF), insulin-like growth factor binding protein-1 (IGFBP-1), mesencephalic astrocyte-derived neurotrophic factor (MANF), calcitonin gene-related peptide (CGRP) and substance P (SP) in stromal lenticules were quantified using ELISA. Multiple linear regression analysis was employed to evaluate the associations between SCL wear duration, mediator levels, and postoperative outcomes.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| SCLs >10 years | – | –myopia patients who wear SCL more than 10 years before Small Incision Lenticule Extraction |
| SCLs ≤10 years | – | –myopia patients who wear SCL for 10 years or less before Small Incision Lenticule Extraction |
| NW | – | –myopia patients who have not worn SCLs before Small Incision Lenticule Extraction |
Who may qualify
- Ages
- 18 to 45 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
- Study population
- patients with myopia who underwent SMILE surgery at Shanghai Tenth People's Hospital in Shanghai, China, from June 2023 to the present.
Key inclusion criteria (3 listed)
- age ≥ 18 years with stable refraction for at least two years;
- corrected distance visual acuity of 20/20 or better;
- no history of using rigid gas permeable lenses or orthokeratology (OK) lenses prior to examination
Key exclusion criteria (1 listed)
- a history of moderate to severe dry eye as well as any ocular or systemic disease that would contraindicate laser refractive surgery.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Quality of Vision (QOV) scores
Time frame: baseline, 1 month, 3months, 6months
It consists of 10 items related to visual symptoms, including glare, halo, radiating light, foggy vision, blurred vision, visual distortion, diplopia, visual fluctuation, difficulty in focusing and difficulty in depth perception. Each item consists of three dimensions: frequency, severity and degree of distress. Therefore, this questionnaire contains a total of 30 questions. The answers to the above three dimensions respectively include four options, namely frequency: never, occasionally, often, and frequently; Severity: None, mild, moderate, severe; Degree of distress: None, a little, some, very much. The corresponding scores for the four options are 0, 1, 2, and 3 respectively. The higher the score, the worse the visual quality
contrast sensitivity function
Time frame: baseline, 1moth, 3 moths, 6 months
Under sufficient correction conditions, dark adaptation lasted for 10 minutes. Using the CSV-1000 contrast sensitivity tester at a distance of 3 meters, under the conditions of bright vision (85 cd/m ²), bright glare (135 lx), dark vision (3 cd/m ²), and dark glare (28 lx) respectively, Test the highest CS level that can be distinguished at 3, 6, 12 and 18 c/d spatial frequencies one by one. At each spatial frequency, the examinee needs to point out the bar grid sight in the upper and lower two circular sight targets and report the direction of the bar grid. After the result is correct, gradually reduce the bar grid contrast until the examinee can no longer recognize it. The inverse of the lowest recognizable contrast at this time is the contrast sensitivity. Record in logarithmic units according to the grade value conversion table.
Corneal subepithelial nerve fibers
Time frame: baseline, 1moth, 3 moths, 6 months
In this study, the ACCMetrics V.2 software developed by the University of Manchester in the UK for the HRT confocal microscope of Heidelberg Company was used to conduct automatic quantitative analysis and data recording on three nerve fiber images at different positions selected in a single shoot. The parameters analyzed include corneal nerve fiber density (CNFD sterand/mm 2) and corneal nerve fiber length( CNFL, mm/mm 2), corneal nerve fiber area (CNFA mm2/mm 2), corneal nerve fiber width (CNFW mm ), etc. Each inspection is carried out by the same inspector to reduce subjective errors.
Corneal stromal lenticule Neuromediators
Time frame: baseline
Corneal neuromediators, including NGF(pg/mL), CGRP(pg/mL), SP(pg/mL), IGFBP-1(ng/mL), and MANF(pg/mL), which play pivotal roles in maintaining normal physiological functions of the cornea.
OSDI Questionnaire
Time frame: baseline, 1moth, 3 moths, 6 months
The impact of dry eye on the subjective symptoms of patients was evaluated from three dimensions: ocular symptoms, visual function, and environmental stimuli. There were a total of 12 items. Each symptom was divided into 5 levels according to the degree and occurrence frequency: 0 was considered as none. 1 point occurs sometimes; 2 minutes occurs approximately half of the time; 3 points occur frequently; 4 points occur continuously. The final OSDI score = the total of all scores ×100/ (the total number of assessment questions ×4), with a total score ranging from 0 to 100.
3 secondary outcomes
Tear film stability
Time frame: baseline, 1moth, 3 moths, 6 months
Corneal Aberration
Time frame: baseline, 1moth, 3 moths, 6 months
Corneal Densitometry
Time frame: baseline, 1moth, 3 moths, 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 20 Jul 2025.
- Individual participant dataSharing planned: No
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?
An observational study of Contact Lens Complication and Small Incision Lenticule Extraction, run by yuhao shao at 1 site in China.
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 1 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 20 Jul 2025. 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 China. 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?
Quality of Vision (QOV) scores (time frame: baseline, 1 month, 3months, 6months). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 20 Jul 2025.