AstigmatismNCT01432834
Efficacy of the Wavefront Optimized (WFO) Profile in Non-anterior Astigmatisms
A study testing Laser in situ keratomileusis (LASIK) and Photorefractive keratectomy (PRK) in people with Astigmatism, run by Democritus University of Thrace at 1 site in Greece.
Trial summary
The purpose of the study was to assess the efficacy of the Allegretto Wave excimer laser and the wavefront optimized ablation profile in correcting primarily non-anterior astigmatism faults, following laser in-situ keratomileusis (LASIK) and photorefractive keratectomy (PRK). Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Astigmatism
- What is being tested?
- Laser in situ keratomileusis (LASIK) and Photorefractive keratectomy (PRK)
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 74 participants
- Where
- 1 siteGreece
- Study dates
- Apr 2010to Apr 2011
- 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 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- astigmatism fault
Who cannot join
- previous incisional eye surgery
- evidence of any type of corneal pathology
- evidence of any type of optic neuropathy
- history of optic neuropathy
- diabetes mellitus
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Evaluation of the Efficacy of the Allegretto Wave and the Wavefront Optimized Ablation Profile in Non-anterior Astigmatisms
The purpose of the study was to assess the efficacy of the Allegretto Wave excimer laser and the wavefront optimized ablation profile in correcting primarily non-anterior astigmatism faults, following laser in-situ keratomileusis (LASIK) and photorefractive keratectomy (PRK).
Read the detailed description
Different optical components of the eye contribute to the total astigmatism error.In specific, the anterior corneal surface is responsible for the anterior component of astigmatism fault (anterior astigmatism), while the posterior corneal surface and the lens are responsible for the posterior one (posterior astigmatism).
Regarding our study, 74 refractive surgery candidates were recruited. Only one eye from each candidate was randomly enrolled in the study. Of them, 40 eyes underwent LASIK treatment (LG group), while 34 eyes underwent PRK treatment (PG group). The Allegretto Wave excimer laser (software version: 2.020 / WaveLight AG, Erlangen, Germany) was used for the ablation in all groups. Preoperatively, the ocular residual astigmatism (ORA) was calculated for each eye, according to which each astigmatism fault was characterized as primarily anterior or non-anterior.ORA is the vectorial value of astigmatism arising from non-anterior sources. Its amount on total astigmatism (R) is determined by the magnitude ratio ORA/R. Ratios below 1 indicate primarily anterior astigmatism, while ratios above 1 indicate primarily non-anterior astigmatism. 20 LG eyes and 16 PG eyes presented primarily anterior astigmatism (LG-A and PG-A subgroups, respectively), while 20 LG eyes and 18 PG eyes demonstrated primarily non-anterior astigmatism (LG-NA and PG-NA subgroups, respectively). Postoperatively, vector analysis of astigmatism correction was conducted; The following indexes were calculated: a) Correction index (CI), b) Difference vector (DV) and c) Index of Success (IOS).
- Conditions
- Astigmatism
- Being tested
- Laser in situ keratomileusis (LASIK), Photorefractive keratectomy (PRK)
- Keywords
- non-anterior astigmatism correction, Allegretto Wave excimer laser, wavefront optimized ablation profile (WFO), LASIK, PRK
- Medical subject headings
- Astigmatism
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Laser in situ keratomileusis (LASIK)Other
Also called Allegretto Wave excimer laser (software version: 2.020 / WaveLight AG, Erlangen, Germany), Carriazo-Pendular microkeratome (SCHWIND eye-tech-solutions GmbH & Co.KG, Kleinostheim, Germany)
During LASIK treatments the Carriazo-Pendular microkeratome (SCHWIND eye-tech-solutions GmbH \& Co.KG, Kleinostheim, Germany) with 130μm cutting head was used for the creation of the flap. The normal value of the negative pressure of the suction ring was between 600-620 mmHg and the velocity of the head movement was constant (3mm/sec). The hinge was created at the 12 o'clock position. The Allegretto Wave excimer laser (software version: 2.020 / WaveLight AG, Erlangen, Germany) was used for all ablations. Attempted ablations were modified according to the "S001 Wellington" nomogram for the "wavefront optimised" protocol.
Photorefractive keratectomy (PRK)Other
Also called Allegretto Wave excimer laser (software version: 2.020 / WaveLight AG, Erlangen, Germany)
The same surgical procedure was applied to all PG participants that included: Instillation of proparacaine hydrochloride 0.5% drops for topical anaesthesia, application of a sponge saturated with 10% alcohol to the central cornea for 20-30 seconds and subsequent de-epithelialization by means of a hockey knife.The Allegretto Wave excimer laser (software version: 2.020 / WaveLight AG, Erlangen, Germany) was used for all ablations. Attempted ablations were modified according to the "S001 Wellington" nomogram for the "wavefront optimised" protocol. A soft therapeutic lens was applied until complete re-epithelialization of the cornea was detected.
| Study group | Role | What they receive |
|---|---|---|
| LASIK group (LG group) | Other | Volunteers of this group received LASIK treatment. Receives: Other: Laser in situ keratomileusis (LASIK) |
| PRK group (PG group) | Other | Volunteers of this group received PRK treatment Receives: Other: Photorefractive keratectomy (PRK) |
What is being measured
The primary outcome is the main question the study is designed to answer.
vector analysis of astigmatism correction, following laser in-situ keratomileusis (LASIK) & photorefractive keratectomy (PRK) treatments.
Vector analysis of astigmatism correction was conducted using preoperative and 6-month postoperative data. The following indexes were calculated: a) Correction index (CI) which is determined by the ratio of the surgically induced astigmatism (SIA) to the target induced astigmatism (TIA), b) Difference vector (DV) as an absolute measure of success, and, c) Index of Success (IOS) which is determined by the relationship of the DV to the TIA, as a relative measure of success.
Measured: 6 months postoperatively
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 Sep 2011 (estimated)
- Study startApr 2010
- Primary completionDec 2010
- Study completionApr 2011
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 AstigmatismStudies 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
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 74 participants (actual)
Sponsor and investigators
- Lead sponsor
- Democritus University of Thrace
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Georgios Labiris, Democritus University of Thrace
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01432834
- Sponsor's protocol ID
- 23/29-07-11
- Status last verified
- Jan 2017
- First submitted
- 12 Sep 2011
- Last updated
- 18 Jan 2017
- Results posted
- No
- Data monitoring committee
- No
Publications
Labiris G, Gatzioufas Z, Giarmoukakis A, Sideroudi H, Kozobolis V. Evaluation of the efficacy of the Allegretto Wave and the Wavefront-optimized ablation profile in non-anterior astigmatisms. Acta Ophthalmol. 2012 Sep;90(6):e442-6. doi: 10.1111/j.1755-3768.2012.02463.x. Epub 2012 Jun 13.
PubMed 22690672
Study at a glance
From the registry record, last updated by the sponsor on 18 Jan 2017. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of the Efficacy of the Allegretto Wave and the Wavefront Optimized Ablation Profile in Non-anterior Astigmatisms
- ClinicalTrials.gov ID
- NCT01432834
- Acronym / sponsor ID
- 23/29-07-11
- Conditions
- Astigmatism
- Keywords
- non-anterior astigmatism correction, Allegretto Wave excimer laser, wavefront optimized ablation profile (WFO), LASIK, PRK
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 74 participants (actual)
- Lead sponsor
- Democritus University of ThraceUniversity, hospital or other
- Study start
- Apr 2010
- Primary completion
- Dec 2010 (actual)
- Study completion
- Apr 2011 (actual)
- First posted
- 13 Sep 2011 (estimated)
- 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.
The purpose of the study was to assess the efficacy of the Allegretto Wave excimer laser and the wavefront optimized ablation profile in correcting primarily non-anterior astigmatism faults, following laser in-situ keratomileusis (LASIK) and photorefractive keratectomy (PRK).
Detailed description
Different optical components of the eye contribute to the total astigmatism error.In specific, the anterior corneal surface is responsible for the anterior component of astigmatism fault (anterior astigmatism), while the posterior corneal surface and the lens are responsible for the posterior one (posterior astigmatism).
Regarding our study, 74 refractive surgery candidates were recruited. Only one eye from each candidate was randomly enrolled in the study. Of them, 40 eyes underwent LASIK treatment (LG group), while 34 eyes underwent PRK treatment (PG group). The Allegretto Wave excimer laser (software version: 2.020 / WaveLight AG, Erlangen, Germany) was used for the ablation in all groups. Preoperatively, the ocular residual astigmatism (ORA) was calculated for each eye, according to which each astigmatism fault was characterized as primarily anterior or non-anterior.ORA is the vectorial value of astigmatism arising from non-anterior sources. Its amount on total astigmatism (R) is determined by the magnitude ratio ORA/R. Ratios below 1 indicate primarily anterior astigmatism, while ratios above 1 indicate primarily non-anterior astigmatism. 20 LG eyes and 16 PG eyes presented primarily anterior astigmatism (LG-A and PG-A subgroups, respectively), while 20 LG eyes and 18 PG eyes demonstrated primarily non-anterior astigmatism (LG-NA and PG-NA subgroups, respectively). Postoperatively, vector analysis of astigmatism correction was conducted; The following indexes were calculated: a) Correction index (CI), b) Difference vector (DV) and c) Index of Success (IOS).
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| LASIK group (LG group) | Other | Other: Laser in situ keratomileusis (LASIK)Volunteers of this group received LASIK treatment. |
| PRK group (PG group) | Other | Other: Photorefractive keratectomy (PRK)Volunteers of this group received PRK treatment |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (1 listed)
- astigmatism fault
Key exclusion criteria (5 listed)
- previous incisional eye surgery
- evidence of any type of corneal pathology
- evidence of any type of optic neuropathy
- history of optic neuropathy
- diabetes mellitus
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 |
|---|---|---|
| Laser in situ keratomileusis (LASIK)Also: Allegretto Wave excimer laser (software version: 2.020 / WaveLight AG, Erlangen, Germany), Carriazo-Pendular microkeratome (SCHWIND eye-tech-solutions GmbH & Co.KG, Kleinostheim, Germany)During LASIK treatments the Carriazo-Pendular microkeratome (SCHWIND eye-tech-solutions GmbH \& Co.KG, Kleinostheim, Germany) with 130μm cutting head was used for the creation of the flap. The normal value of the negative pressure of the suction ring was between 600-620 mmHg and the velocity of the head movement was constant (3mm/sec). The hinge was created at the 12 o'clock position. The Allegretto Wave excimer laser (software version: 2.020 / WaveLight AG, Erlangen, Germany) was used for all ablations. Attempted ablations were modified according to the "S001 Wellington" nomogram for the "wavefront optimised" protocol. | Other | LASIK group (LG group) |
| Photorefractive keratectomy (PRK)Also: Allegretto Wave excimer laser (software version: 2.020 / WaveLight AG, Erlangen, Germany)The same surgical procedure was applied to all PG participants that included: Instillation of proparacaine hydrochloride 0.5% drops for topical anaesthesia, application of a sponge saturated with 10% alcohol to the central cornea for 20-30 seconds and subsequent de-epithelialization by means of a hockey knife.The Allegretto Wave excimer laser (software version: 2.020 / WaveLight AG, Erlangen, Germany) was used for all ablations. Attempted ablations were modified according to the "S001 Wellington" nomogram for the "wavefront optimised" protocol. A soft therapeutic lens was applied until complete re-epithelialization of the cornea was detected. | Other | PRK group (PG group) |
Primary outcome
vector analysis of astigmatism correction, following laser in-situ keratomileusis (LASIK) & photorefractive keratectomy (PRK) treatments.
Time frame: 6 months postoperatively
Vector analysis of astigmatism correction was conducted using preoperative and 6-month postoperative data. The following indexes were calculated: a) Correction index (CI) which is determined by the ratio of the surgically induced astigmatism (SIA) to the target induced astigmatism (TIA), b) Difference vector (DV) as an absolute measure of success, and, c) Index of Success (IOS) which is determined by the relationship of the DV to the TIA, as a relative measure of success.
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 18 Jan 2017.
- Results publication: PubMed 22690672Labiris G, Gatzioufas Z, Giarmoukakis A, Sideroudi H, Kozobolis V. Evaluation of the efficacy of the Allegretto Wave and the Wavefront-optimized ablation profile in non-anterior astigmatisms. Acta Ophthalmol. 2012 Sep;90(6):e442-6. doi: 10.1111/j.1755-3768.2012.02463.x. Epub 2012 Jun 13.
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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 Laser in situ keratomileusis (LASIK) and Photorefractive keratectomy (PRK) in people with Astigmatism, run by Democritus University of Thrace at 1 site in Greece.
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 1 inclusion and 5 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 18 Jan 2017. 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 Greece. 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?
vector analysis of astigmatism correction, following laser in-situ keratomileusis (LASIK) & photorefractive keratectomy (PRK) treatments. (time frame: 6 months postoperatively). 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 NCT01432834, 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 18 Jan 2017.