Laser Assisted Procedures in Penetrating Keratoplasty
Primary Purpose
Keratoconus, Corneal Dystrophies, Corneal Opacity
Status
Completed
Phase
Not Applicable
Locations
Italy
Study Type
Interventional
Intervention
Penetrating keratoplasty
Femtosecond laser
Diode laser
Sponsored by
About this trial
This is an interventional treatment trial for Keratoconus focused on measuring anvil-shaped corneal graft, penetrating keratoplasty, femtosecond laser, laser welding
Eligibility Criteria
Inclusion Criteria:
- Corneal dystrophy
- keratoconus in its final stages
- post-herpetic leukoma
- corneal scar
Exclusion Criteria:
- systemic diseases
- previous corneal surgery
- glaucoma
Sites / Locations
- U.O. Oculistica Nuovo Ospedale S. Stefano
Arms of the Study
Arm 1
Arm Type
Experimental
Arm Label
Penetrating keratoplasty
Arm Description
Femtosecond laser sculptured anvil graft. Diode laser welding of the flap in its final position. 12 months follow up study
Outcomes
Primary Outcome Measures
Change in best spectacle-corrected distance visual acuity (CDVA)
documentation of the visual acuity of patients
Secondary Outcome Measures
Change in objective astigmatism and specular corneal topography
Objective astigmatism and specular corneal topography were evaluated by using a topographer-pachymeter
Full Information
NCT ID
NCT02173847
First Posted
May 30, 2014
Last Updated
June 23, 2014
Sponsor
Ospedale Santo Stefano
Collaborators
Istituto di Fisica Applicata
1. Study Identification
Unique Protocol Identification Number
NCT02173847
Brief Title
Laser Assisted Procedures in Penetrating Keratoplasty
Official Title
Laser Assisted Procedures in Penetrating Keratoplasty: Femtosecond Laser Anvil-shaped Cuts and Laser Welding of the Surgical Wounds
Study Type
Interventional
2. Study Status
Record Verification Date
June 2014
Overall Recruitment Status
Completed
Study Start Date
January 2011 (undefined)
Primary Completion Date
January 2013 (Actual)
Study Completion Date
September 2013 (Actual)
3. Sponsor/Collaborators
Responsible Party, by Official Title
Sponsor
Name of the Sponsor
Ospedale Santo Stefano
Collaborators
Istituto di Fisica Applicata
4. Oversight
Data Monitoring Committee
No
5. Study Description
Brief Summary
Laser- assisted procedures in penetrating keratoplasty (PK) are proposed to improve the surgical outcomes: minimally invasive procedures, improved biomechanical stability of the transplanted flap, reduction of rejection risks, reduction of inflammation, reduction of infections risk, faster healing process.
In order to achieve these goals, two different lasers were used during PK surgery:
a femtosecond laser to cut an anvil shaped profile
a diode laser to weld the surgical wound
Detailed Description
The femtosecond laser is used to cut an anvil-shaped laser incision used in PK. This design has the purpose to create a more structurally stable and predictable wound configuration with the aim of a faster recovery of vision and higher optical quality, compared with the conventional blade trephination and the most common laser-cut patterns. The "anvil" profile is designed as described in the followings. Donor and recipient corneal trephination are performed using a 150 kHz FS laser (iFS150TM, IntralaseTM FS Laser, Abbott Medical Optics -AMO, Santa Ana, CA, USA). As concerned iFS150 settings, we refer to the following technical parameters: in the donor graft, the outer and inner diameters of the ring lamellar cut at 350 µm in depth were set at 8.5 mm and 6.6 mm, respectively; the anterior-side cut started with an angle of 135° at a diameter of 7.7 mm, while the straight posterior side cut diameter was 6.7 mm. In the recipient eye, the diameters were designed to be 0.2 mm shorter (8.3 mm outer diameter, 6.4 mm inner diameter, 7.5 mm anterior side cut and 6.5 mm posterior side cut). After completion of the trephination, the corneal button was gently lifted from the host and the donor graft was secured in place on the recipient bed by means of 10-0 nylon cardinal sutures, which were removed after the final 16-running 10-0 nylon suture was completed. A similar FS-laser cut procedure producing a 0.2 mm-narrower corneal bed -diameter is performed on the patient's recipient eye. After completion of the trephination, the corneal button is lifted gently from the host and the donor graft is secured into place with 10-0 nylon cardinal sutures, that are removed as a running 10-0 nylon suture is placed.
The particular "anvil" shape of the graft provides a larger contact surface in between donor and recipient cornea, which enables an effective application of the diode laser welding technique of corneal wounds we have previously set up in cataract and PK applications (Menabuoni et al. 2007, Rossi et al. 2008). This laser-assisted suturing technique is based on the photothermal activation of the stromal collagen, providing an immediate sealing of the surgical wound and a good stabilization of the graft. Once the donor graft was sutured in its final position, diode laser welding was performed. A sterile saturated water solution of 10% w/v Indocyanine Green (ICG) (Pulsion Medical System AG, Munich, Germany) was prepared and applied to the walls of the surgical wound at the donor-recipient interface. A mild photothermal effect was induced by means of a near infrared diode laser (Mod. WELD 800, El.En., Calenzano, FI, Italy) that emitted at 810 nm. The laser light was delivered through a 300-micron core diameter optical fiber that was mounted on a handpiece and used "as a pencil" by the surgeon under a surgical microscope. In a slow, continuous/fluid motion, the surgeon moved the fiber tip along the wound edge at a distance of 1.5 mm from the external surface of the cornea. The power radiation emitted was a 60 mW continuous wave, which resulted in an 8 W/cm2 power density on the tissue surface. The laser welding treatment time was set at 130s.
Thanks two the combine laser assisted procedures, the possible reduction of suture materials allows a faster and improved the healing process, with minimal inflammation and reaction. Thus the combination of FS laser trephination with the diode laser welding technique may provide extremely precise, and minimally invasive surgical procedures in PK.
6. Conditions and Keywords
Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Keratoconus, Corneal Dystrophies, Corneal Opacity
Keywords
anvil-shaped corneal graft, penetrating keratoplasty, femtosecond laser, laser welding
7. Study Design
Primary Purpose
Treatment
Study Phase
Not Applicable
Interventional Study Model
Single Group Assignment
Masking
None (Open Label)
Allocation
N/A
Enrollment
22 (Actual)
8. Arms, Groups, and Interventions
Arm Title
Penetrating keratoplasty
Arm Type
Experimental
Arm Description
Femtosecond laser sculptured anvil graft. Diode laser welding of the flap in its final position. 12 months follow up study
Intervention Type
Procedure
Intervention Name(s)
Penetrating keratoplasty
Intervention Description
Femtosecond laser sculptured anvil graft. Laser welding of the flap in its final position. 12 months follow up study
Intervention Type
Device
Intervention Name(s)
Femtosecond laser
Intervention Description
A commercial femtosecond laser to cut a particular shaped graft
Intervention Type
Device
Intervention Name(s)
Diode laser
Intervention Description
Low power, near infrared diode laser for welding the surgical wound
Primary Outcome Measure Information:
Title
Change in best spectacle-corrected distance visual acuity (CDVA)
Description
documentation of the visual acuity of patients
Time Frame
1 day, 7 days, 1 month, 3 months, 6 months, and 12 months after surgery
Secondary Outcome Measure Information:
Title
Change in objective astigmatism and specular corneal topography
Description
Objective astigmatism and specular corneal topography were evaluated by using a topographer-pachymeter
Time Frame
1 day, 7 days, 1 month, 3 months, 6 months, and 12 months after surgery
Other Pre-specified Outcome Measures:
Title
Change in anterior segment optical coherence tomography
Description
All patients underwent anterior segment optical coherence tomography to evaluate wound alignment and suture configurations
Time Frame
1 day, 7 days, 1 month, 3 months, 6 months, and 12 months after surgery
10. Eligibility
Sex
All
Minimum Age & Unit of Time
16 Years
Maximum Age & Unit of Time
75 Years
Accepts Healthy Volunteers
No
Eligibility Criteria
Inclusion Criteria:
Corneal dystrophy
keratoconus in its final stages
post-herpetic leukoma
corneal scar
Exclusion Criteria:
systemic diseases
previous corneal surgery
glaucoma
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Luca Menabuoni, MD
Organizational Affiliation
Head of Corneal and Experimental Surgery at the Department of Ophthalmology
Official's Role
Principal Investigator
Facility Information:
Facility Name
U.O. Oculistica Nuovo Ospedale S. Stefano
City
Prato
ZIP/Postal Code
59100
Country
Italy
12. IPD Sharing Statement
Citations:
PubMed Identifier
24140371
Citation
Buzzonetti L, Capozzi P, Petrocelli G, Valente P, Petroni S, Menabuoni L, Rossi F, Pini R. Laser welding in penetrating keratoplasty and cataract surgery in pediatric patients: early results. J Cataract Refract Surg. 2013 Dec;39(12):1829-34. doi: 10.1016/j.jcrs.2013.05.046. Epub 2013 Oct 18.
Results Reference
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PubMed Identifier
19343656
Citation
Rossi F, Matteini P, Ratto F, Menabuoni L, Lenzetti I, Pini R. Laser tissue welding in ophthalmic surgery. J Biophotonics. 2008 Sep;1(4):331-42. doi: 10.1002/jbio.200810028.
Results Reference
background
PubMed Identifier
17720078
Citation
Menabuoni L, Pini R, Rossi F, Lenzetti I, Yoo SH, Parel JM. Laser-assisted corneal welding in cataract surgery: retrospective study. J Cataract Refract Surg. 2007 Sep;33(9):1608-12. doi: 10.1016/j.jcrs.2007.04.013.
Results Reference
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PubMed Identifier
17343506
Citation
Rossi F, Pini R, Menabuoni L. Experimental and model analysis on the temperature dynamics during diode laser welding of the cornea. J Biomed Opt. 2007 Jan-Feb;12(1):014031. doi: 10.1117/1.2437156.
Results Reference
background
PubMed Identifier
15910078
Citation
Rossi F, Pini R, Menabuoni L, Mencucci R, Menchini U, Ambrosini S, Vannelli G. Experimental study on the healing process following laser welding of the cornea. J Biomed Opt. 2005 Mar-Apr;10(2):024004. doi: 10.1117/1.1900703.
Results Reference
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PubMed Identifier
23617376
Citation
Menabuoni L, Canovetti A, Rossi F, Malandrini A, Lenzetti I, Pini R. The 'anvil' profile in femtosecond laser-assisted penetrating keratoplasty. Acta Ophthalmol. 2013 Sep;91(6):e494-5. doi: 10.1111/aos.12144. Epub 2013 Apr 26. No abstract available.
Results Reference
background
PubMed Identifier
17868101
Citation
Matteini P, Rossi F, Menabuoni L, Pini R. Microscopic characterization of collagen modifications induced by low-temperature diode-laser welding of corneal tissue. Lasers Surg Med. 2007 Aug;39(7):597-604. doi: 10.1002/lsm.20532.
Results Reference
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Links:
URL
http://www.usl4.toscana.it/?act=f&fid=758
Description
Information about the Ophthalmology Department of the Prato Hospital
Learn more about this trial
Laser Assisted Procedures in Penetrating Keratoplasty
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