Clinical trial NCT04426175: Z8 OCT-controlled 2D vs 3D LASIK
Official title: Precision of 2D vs 3D Low Energy Femto-LASIK: Intraoperative and Postoperative OCT-based Study
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Myopia
Astigmatism
Keywords: Femtosecond Laser Assisted Laser in Situ Keratomileusis
LASIK
FEMTO LDV Z8
Lead sponsor: Zentrumsehstarke Hamburg
Sponsor class: INDUSTRY
First posted: 2020-06-11
Enrollment: 13
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: The aim of this study was to test the hypothesis that OCT-guided 110 µm targeted flaps will result in accurate, predictable, and precise thickness flaps, with low complication rates when performed and compared using both 2D and 3D flap geometry applications and how it correlated to visual experience and quality of life responses during the early postoperative period.

Detailed description: It has been postulated that it is possible with the Ziemer Femtosecond LDV laser system to create reproducible flaps in terms of thickness and predictability. The aim of this study was to test the hypothesis that OCT-guided 110 µm targeted flaps will result in accurate, predictable, and precise thickness flaps, with low complication rates when performed and compared using both 2D and 3D flap geometry applications. Patient-reported outcomes are increasingly incorporated into clinical trials as they provide access to valuable information on the physical experience of the patient during and after the treatment. A questionnaire will therefore also be introduced in this study to evaluate how well self-reported pain, visual experience, and quality of life responses are correlated with flap geometries in both groups during the early postoperative period. The study holds direct medical benefit to the patient in this that they received an immediate improvement in his/her unaided vision. Moreover, the patient's participation contributes to the medical knowledge about the use of femtosecond lasers for refractive surgery, in particular in view of the use of intraoperative OCT visualization tools. The patients will gain access to the newest technology available for refractive surgery namely a low pulse energy high-frequency femtosecond laser.

Eligibility criteria: Inclusion Criteria:

Key inclusion criteria as described by the German Commission for Refractive Surgery (KRC) are:

* The recommended range of application for the correction of myopia is up to -8.00 D and for the correction of astigmatism up to 5.00 D.
* The limited for LASIK correction of myopia is up to -10.00 D and correction of astigmatism up to 6.00 D. If myopic astigmatism is to be corrected, the values for myopia and astigmatism must be added together.
* The recommended range for correction of hyperopia is up to 3.00 D. Up to 4.00 D is the range of limited application for hyperopia.
* Age ≥18 years with stable eyesight for over 12 months.

Exclusion Criteria:

Key exclusion criteria as described by the German Commission for Refractive Surgery (KRC):

* preoperative corneal thickness less than 480 μm
* predicted stromal thickness under the flap after ablation of less than 250 μm
* chronic progressive corneal disease and forme fruste keratoconus
* surgery before the age of 18 years
* symptomatic cataract
* Glaucoma with a marked loss of visual field
* Exudative macular degeneration.
* Concurrent participation in another ophthalmological clinical study

Exclusion criteria irrespective of the KRC criteria:

* Undergone former eye surgery
* Contact lens wear within the two weeks prior to commencement of preoperative measurements

Primary outcomes:
measure: Predictability of central flap thickness in OCT-controlled 110 µm LASIK
timeFrame: 1 month postoperatively
Secondary outcomes:
measure: Comparison of intraoperative flap thickness with pre- and postoperative results
timeFrame: 1 week, 1 month
measure: Postoperative planarity
timeFrame: 1 week, 1 month
measure: Intraoperative flap morphology
timeFrame: During surgery
measure: Postoperative flap properties
timeFrame: 1 week, 1 month
measure: Visual outcomes
timeFrame: 1 day, 1 week, 1 month
measure: Patient reported Outcomes: early recovery period
timeFrame: 1 day, 2Day, 1 week follow up
measure: Complications
timeFrame: Intra- and postoperatively up to 1 month follow up
Other outcomes:
Locations:
city: Hamburg
country: Germany
facility: Zentrumsehstärke
Study officials:
affiliation: Zentrumsehstarke Hamburg
name: Stephan Linke, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Huhtala A, Pietila J, Makinen P, Uusitalo H. Femtosecond lasers for laser in situ keratomileusis: a systematic review and meta-analysis. Clin Ophthalmol. 2016 Mar 7;10:393-404. doi: 10.2147/OPTH.S99394. eCollection 2016.
citation: Eldaly ZH, Abdelsalam MA, Hussein MS, Nassr MA. Comparison of Laser In Situ Keratomileusis Flap Morphology and Predictability by WaveLight FS200 Femtosecond Laser and Moria Microkeratome: An Anterior Segment Optical Coherence Tomography Study. Korean J Ophthalmol. 2019 Apr;33(2):113-121. doi: 10.3341/kjo.2018.0035.
citation: Pajic B, Vastardis I, Pajic-Eggspuehler B, Gatzioufas Z, Hafezi F. Femtosecond laser versus mechanical microkeratome-assisted flap creation for LASIK: a prospective, randomized, paired-eye study. Clin Ophthalmol. 2014 Sep 22;8:1883-9. doi: 10.2147/OPTH.S68124. eCollection 2014.
citation: Tomita M, Chiba A, Matsuda J, Nawa Y. Evaluation of LASIK treatment with the Femto LDV in patients with corneal opacity. J Refract Surg. 2012 Jan;28(1):25-30. doi: 10.3928/1081597X-20111213-01. Epub 2011 Dec 19.
citation: Pietila J, Huhtala A, Makinen P, Uusitalo H. Flap characteristics, predictability, and safety of the Ziemer FEMTO LDV femtosecond laser with the disposable suction ring for LASIK. Eye (Lond). 2014 Jan;28(1):66-71. doi: 10.1038/eye.2013.244. Epub 2013 Nov 15.
citation: Pietila J, Huhtala A, Makinen P, Salmenhaara K, Uusitalo H. Laser-assisted in situ keratomileusis flap creation with the three-dimensional, transportable Ziemer FEMTO LDV model Z6 I femtosecond laser. Acta Ophthalmol. 2014 Nov;92(7):650-5. doi: 10.1111/aos.12333. Epub 2013 Dec 26.
citation: Porela-Tiihonen S, Kaarniranta K, Kokki M, Purhonen S, Kokki H. A prospective study on postoperative pain after cataract surgery. Clin Ophthalmol. 2013;7:1429-35. doi: 10.2147/OPTH.S47576. Epub 2013 Jul 15.