Intraocular Lens DislocationHORVERNCT07701980
Horizontal vs Vertical Scleral Tunnels in Flanged IOL Fixation
An observational study of Intraocular Lens Dislocation and Aphakia - No Lens Capsule, run by Yuzuncu Yil University at 1 site in Turkey (Türkiye).
Trial summary
This study compares the 2-year outcomes of horizontal versus vertical scleral tunnel orientation in flanged intrascleral intraocular lens (IOL) fixation surgery. The primary outcome is the proportion of eyes achieving refraction within ±0.50 diopters of the target at 2 years. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Intraocular Lens Dislocation, Aphakia - No Lens Capsule
- What is being tested?
- Flanged Intrascleral IOL Fixation (Yamane Technique)
- Type of treatment
- Surgery or procedure
- How many people
- 107 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 1 Mar 2022to 1 Mar 2025
- How long will I take part?
- 24 Months
- 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 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Patients with aphakia, crystalline lens luxation, or intraocular lens luxation in the absence of adequate capsular support who underwent flanged intrascleral IOL fixation surgery at a single tertiary referral centre between March 1, 2022, and March 1, 2025. All patients were aged 18 years or older and completed 24 months of follow-up.
Who may be able to join
- Age ≥ 18 years
- Complicated aphakia defined as absence of adequate capsular support following cataract extraction, lens trauma, or previous lensectomy
- Crystalline lens luxation defined as partial or complete displacement of the natural lens due to zonular weakness
- Intraocular lens (IOL) luxation defined as partial or complete dislocation of a previously implanted IOL
- Inadequate capsular support (<180° of intact zonular or capsular support)
- Ability to complete scheduled follow-up visits
- Complete follow-up data available
Who cannot join
- Previous scleral buckling surgery within 6 months
- Pars plana vitrectomy within 3 months
- Active uveitis
- Active endophthalmitis
- Uncontrolled scleritis or scleral thinning
- Corneal decompensation (endothelial cell density <1000 cells/mm²)
Show all 12Show fewer
- Uncontrolled glaucoma (IOP >25 mmHg despite maximum therapy)
- History of penetrating keratoplasty, DALK, DSEK, or DMEK
- History of corneal refractive surgery
- Active proliferative diabetic retinopathy
- Pregnancy or breastfeeding
- Inability to complete 24-month follow-up
Trial locations and contacts
1 site in 1 country.
Turkey (Türkiye)1 site
SBU Van Training and Research Hospital
Van, 65000
About this study
Official title: Horizontal Versus Vertical Scleral Tunnel Orientation in Flanged Intrascleral Fixation: A 2-Year Comparative Study
This study compares the 2-year outcomes of horizontal versus vertical scleral tunnel orientation in flanged intrascleral intraocular lens (IOL) fixation surgery. The primary outcome is the proportion of eyes achieving refraction within ±0.50 diopters of the target at 2 years. Secondary outcomes include IOL tilt measured by anterior segment optical coherence tomography (AS-OCT), iris capture, conjunctival erosion, and other complications. The study aims to determine whether tunnel orientation is associated with differing outcomes in this surgical technique.
Read the detailed description
Background: The management of aphakia, crystalline lens luxation, and intraocular lens (IOL) luxation in the absence of adequate capsular support remains challenging. Traditional surgical options include anterior chamber IOLs, iris-fixated IOLs, and scleral-sutured posterior chamber IOLs, each carrying significant long-term risks. In 2017, Yamane and colleagues introduced a sutureless flanged intrascleral IOL fixation technique that rapidly gained worldwide acceptance. A critical yet under-investigated surgical variable is the orientation of the scleral tunnels relative to the limbus. Some surgeons create tunnels parallel to the limbus (horizontal/tangential), others perpendicular (vertical/radial), based on personal preference rather than high-level evidence.
Objective: To evaluate whether horizontal versus vertical scleral tunnel orientation is associated with differing 2-year outcomes in flanged intrascleral IOL fixation.
Study Design: This is a retrospective observational cohort study conducted at a single tertiary referral centre.
Participants: A total of 107 eyes (43 vertical tunnels, 64 horizontal tunnels) with complete 24-month follow-up are included. Surgeries are performed by two experienced vitreoretinal surgeons.
Interventions: All procedures follow the original Yamane flanged intrascleral fixation method with intentional variation in tunnel orientation only. The horizontal tunnel group receives tunnels parallel to the limbus (tangential), while the vertical tunnel group receives tunnels perpendicular to the limbus (radial). A three-piece foldable acrylic IOL (Alcon AcrySof MA60AC) is used in all eyes.
Outcome Measures: The primary outcome is the proportion of eyes achieving mean absolute error (MAE) within ±0.50D of target refraction at 2 years. Secondary outcomes include MAE at 2 years, IOL tilt measured using anterior segment optical coherence tomography (AS-OCT), iris capture, conjunctival erosion, cystoid macular oedema, epiretinal membrane, retinal detachment, vitreous haemorrhage, hypotony, corneal oedema, early IOP elevation, best-corrected visual acuity (BCVA), and vector astigmatism analysis using the Alpins method.
Statistical Analysis: Propensity score matching (1:1) will be performed to address selection bias. Multivariate logistic regression and a multilevel mixed-effects model with surgeon as random effect will be used to adjust for confounders including surgical period, age, and baseline refraction. For the primary outcome, a single pre-specified comparison will be made with a two-tailed significance level of α = 0.05. For secondary outcomes, the False Discovery Rate (FDR) using the Benjamini-Hochberg procedure (q = 0.05) will be applied to control for Type I error inflation.
Timeline: Data were collected from patients who underwent surgery between March 1, 2022, and March 1, 2025. Minimum follow-up is 24 months, with final data collection completed in March 2025.
- Being tested
- Flanged Intrascleral IOL Fixation (Yamane Technique)
- Keywords
- Flanged intrascleral IOL fixation, Yamane technique, scleral tunnel orientation, IOL tilt
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Flanged Intrascleral IOL Fixation (Yamane Technique)Procedure or surgery
Sutureless flanged intrascleral fixation of a three-piece foldable acrylic IOL (Alcon AcrySof MA60AC). Two partial-thickness scleral tunnels are created 2.0 mm posterior to the limbus, 180° apart. Haptics are externalized through the tunnels, and a flange is created on each haptic tip using thermal cautery. Tunnel orientation varied intentionally: horizontal (parallel to limbus) or vertical (perpendicular to limbus).
| Study group | Role | What they receive |
|---|---|---|
| Vertical Scleral Tunnel Group | Patients who underwent flanged intrascleral IOL fixation with scleral tunnels created perpendicular to the limbus (radial/vertical orientation). Receives: Procedure: Flanged Intrascleral IOL Fixation (Yamane Technique) | |
| Horizontal Scleral Tunnel Group | Patients who underwent flanged intrascleral IOL fixation with scleral tunnels created parallel to the limbus (tangential/horizontal orientation). Receives: Procedure: Flanged Intrascleral IOL Fixation (Yamane Technique) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Proportion of Eyes Achieving Mean Absolute Error (MAE) Within ±0.50 Diopters of Target Refraction
The proportion of eyes achieving mean absolute error (MAE) within ±0.50 diopters of the target spherical equivalent refraction at 24 months postoperatively.
Measured: 24 Months
Secondary outcomes (2)
Mean Absolute Error (MAE) at 2 Years
Mean absolute error in spherical equivalent refraction at 24 months postoperatively.
Measured: 24 Months
IOL Tilt Angle
Intraocular lens tilt angle measured using anterior segment optical coherence tomography (AS-OCT) at 24 months postoperatively.
Measured: 24 Months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Jul 2026
- Study start1 Mar 2022
- Primary completion1 Mar 2025
- Study completion1 Mar 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Intraocular Lens DislocationStudies 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
- Other
- Enrolment
- 107 participants (actual)
- Target duration
- 24 Months
Sponsor and investigators
- Lead sponsor
- Yuzuncu Yil University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Sebahattin Celik MD, Yuzuncu Yil University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07701980
- Sponsor's protocol ID
- GOKAEK-2024-04-02
- Other IDs
- GOKAEK-2024-04-02
- Acronym
- HORVER
- Status last verified
- Jul 2026
- First submitted
- 1 Jul 2026
- Last updated
- 14 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data will not be shared due to institutional data protection policies and patient privacy regulations. Anonymized aggregate data may be available from the corresponding author upon reasonable request.
Publications
Yamane S, Sato S, Maruyama-Inoue M, Kadonosono K. Flanged Intrascleral Intraocular Lens Fixation with Double-Needle Technique. Ophthalmology. 2017 Aug;124(8):1136-1142. doi: 10.1016/j.ophtha.2017.03.036. Epub 2017 Apr 27.
PubMed 28457613
Study at a glance
From the registry record, last updated by the sponsor on 14 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Horizontal Versus Vertical Scleral Tunnel Orientation in Flanged Intrascleral Fixation: A 2-Year Comparative Study
- ClinicalTrials.gov ID
- NCT07701980
- Acronym / sponsor ID
- HORVER / GOKAEK-2024-04-02
- Keywords
- Flanged intrascleral IOL fixation, Yamane technique, scleral tunnel orientation, IOL tilt
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 107 participants (actual)
- Lead sponsor
- Yuzuncu Yil UniversityUniversity, hospital or other
- Study start
- 1 Mar 2022 (actual)
- Primary completion
- 1 Mar 2025 (actual)
- Study completion
- 1 Mar 2025 (actual)
- First posted
- 14 Jul 2026 (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.
This study compares the 2-year outcomes of horizontal versus vertical scleral tunnel orientation in flanged intrascleral intraocular lens (IOL) fixation surgery. The primary outcome is the proportion of eyes achieving refraction within ±0.50 diopters of the target at 2 years. Secondary outcomes include IOL tilt measured by anterior segment optical coherence tomography (AS-OCT), iris capture, conjunctival erosion, and other complications. The study aims to determine whether tunnel orientation is associated with differing outcomes in this surgical technique.
Detailed description
Background: The management of aphakia, crystalline lens luxation, and intraocular lens (IOL) luxation in the absence of adequate capsular support remains challenging. Traditional surgical options include anterior chamber IOLs, iris-fixated IOLs, and scleral-sutured posterior chamber IOLs, each carrying significant long-term risks. In 2017, Yamane and colleagues introduced a sutureless flanged intrascleral IOL fixation technique that rapidly gained worldwide acceptance. A critical yet under-investigated surgical variable is the orientation of the scleral tunnels relative to the limbus. Some surgeons create tunnels parallel to the limbus (horizontal/tangential), others perpendicular (vertical/radial), based on personal preference rather than high-level evidence.
Objective: To evaluate whether horizontal versus vertical scleral tunnel orientation is associated with differing 2-year outcomes in flanged intrascleral IOL fixation.
Study Design: This is a retrospective observational cohort study conducted at a single tertiary referral centre.
Participants: A total of 107 eyes (43 vertical tunnels, 64 horizontal tunnels) with complete 24-month follow-up are included. Surgeries are performed by two experienced vitreoretinal surgeons.
Interventions: All procedures follow the original Yamane flanged intrascleral fixation method with intentional variation in tunnel orientation only. The horizontal tunnel group receives tunnels parallel to the limbus (tangential), while the vertical tunnel group receives tunnels perpendicular to the limbus (radial). A three-piece foldable acrylic IOL (Alcon AcrySof MA60AC) is used in all eyes.
Outcome Measures: The primary outcome is the proportion of eyes achieving mean absolute error (MAE) within ±0.50D of target refraction at 2 years. Secondary outcomes include MAE at 2 years, IOL tilt measured using anterior segment optical coherence tomography (AS-OCT), iris capture, conjunctival erosion, cystoid macular oedema, epiretinal membrane, retinal detachment, vitreous haemorrhage, hypotony, corneal oedema, early IOP elevation, best-corrected visual acuity (BCVA), and vector astigmatism analysis using the Alpins method.
Statistical Analysis: Propensity score matching (1:1) will be performed to address selection bias. Multivariate logistic regression and a multilevel mixed-effects model with surgeon as random effect will be used to adjust for confounders including surgical period, age, and baseline refraction. For the primary outcome, a single pre-specified comparison will be made with a two-tailed significance level of α = 0.05. For secondary outcomes, the False Discovery Rate (FDR) using the Benjamini-Hochberg procedure (q = 0.05) will be applied to control for Type I error inflation.
Timeline: Data were collected from patients who underwent surgery between March 1, 2022, and March 1, 2025. Minimum follow-up is 24 months, with final data collection completed in March 2025.
Study design
- Observational model
- Cohort
- Time perspective
- Other
- Target follow-up
- 24 Months
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Vertical Scleral Tunnel Group | – | Procedure: Flanged Intrascleral IOL Fixation (Yamane Technique)Patients who underwent flanged intrascleral IOL fixation with scleral tunnels created perpendicular to the limbus (radial/vertical orientation). |
| Horizontal Scleral Tunnel Group | – | Procedure: Flanged Intrascleral IOL Fixation (Yamane Technique)Patients who underwent flanged intrascleral IOL fixation with scleral tunnels created parallel to the limbus (tangential/horizontal orientation). |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patients with aphakia, crystalline lens luxation, or intraocular lens luxation in the absence of adequate capsular support who underwent flanged intrascleral IOL fixation surgery at a single tertiary referral centre between March 1, 2022, and March 1, 2025. All patients were aged 18 years or older and completed 24 months of follow-up.
Key inclusion criteria (7 listed)
- Age ≥ 18 years
- Complicated aphakia defined as absence of adequate capsular support following cataract extraction, lens trauma, or previous lensectomy
- Crystalline lens luxation defined as partial or complete displacement of the natural lens due to zonular weakness
- Intraocular lens (IOL) luxation defined as partial or complete dislocation of a previously implanted IOL
- Inadequate capsular support (<180° of intact zonular or capsular support)
Key exclusion criteria (12 listed)
- Previous scleral buckling surgery within 6 months
- Pars plana vitrectomy within 3 months
- Active uveitis
- Active endophthalmitis
- Uncontrolled scleritis or scleral thinning
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 |
|---|---|---|
| Flanged Intrascleral IOL Fixation (Yamane Technique)Sutureless flanged intrascleral fixation of a three-piece foldable acrylic IOL (Alcon AcrySof MA60AC). Two partial-thickness scleral tunnels are created 2.0 mm posterior to the limbus, 180° apart. Haptics are externalized through the tunnels, and a flange is created on each haptic tip using thermal cautery. Tunnel orientation varied intentionally: horizontal (parallel to limbus) or vertical (perpendicular to limbus). | Procedure or surgery | Horizontal Scleral Tunnel Group, Vertical Scleral Tunnel Group |
Primary outcome
Proportion of Eyes Achieving Mean Absolute Error (MAE) Within ±0.50 Diopters of Target Refraction
Time frame: 24 Months
The proportion of eyes achieving mean absolute error (MAE) within ±0.50 diopters of the target spherical equivalent refraction at 24 months postoperatively.
2 secondary outcomes
Mean Absolute Error (MAE) at 2 Years
Time frame: 24 Months
IOL Tilt Angle
Time frame: 24 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 14 Jul 2026.
- Results publication: PubMed 28457613Yamane S, Sato S, Maruyama-Inoue M, Kadonosono K. Flanged Intrascleral Intraocular Lens Fixation with Double-Needle Technique. Ophthalmology. 2017 Aug;124(8):1136-1142. doi: 10.1016/j.ophtha.2017.03.036. Epub 2017 Apr 27.
- Individual participant dataSharing planned: No. Individual participant data will not be shared due to institutional data protection policies and patient privacy regulations. Anonymized aggregate data may be available from the corresponding author upon reasonable request.
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 Intraocular Lens Dislocation and Aphakia - No Lens Capsule, run by Yuzuncu Yil University at 1 site in Turkey (Türkiye).
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 7 inclusion and 12 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 14 Jul 2026. 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 Turkey (Türkiye). 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?
Proportion of Eyes Achieving Mean Absolute Error (MAE) Within ±0.50 Diopters of Target Refraction (time frame: 24 Months). 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 NCT07701980, which also lists 1 linked publication.
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 14 Jul 2026.