Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Freezing increment in keratophakia.

C A Swinger, H J Wisnicki

    Cornea
    |January 1, 1985
    PubMed
    Summary
    This summary is machine-generated.

    Accurate measurement of corneal tissue thickness changes during freezing is crucial in refractive surgery. Using an assumed 9.08% freezing increment can lead to significant refractive errors, unlike direct measurements.

    Related Concept Videos

    You might also read

    Related Articles

    Articles linked to this work by shared authors, journal, and citation graph.

    Sort by
    Same author

    Fitting contact lenses after myopic keratomileusis.

    Journal of cataract and refractive surgery·1999
    Same author

    Reproducibility of videokeratographic digital subtraction maps after excimer laser photorefractive keratectomy.

    Ophthalmology·1996
    Same author

    Retinal artery embolization: a rare presentation of calcific aortic stenosis.

    Clinical cardiology·1996
    Same author

    Excimer laser photorefractive keratectomy after radial keratotomy.

    Journal of refractive surgery (Thorofare, N.J. : 1995)·1995
    Same author

    Origin of the foveal granular pattern in entoptic viewing.

    Investigative ophthalmology & visual science·1994
    Same author

    Deteriorated accommodative esotropia.

    Bulletin de la Societe belge d'ophtalmologie·1994
    Same journal

    Corneal Tissue Addition Keratoplasty.

    Cornea·2026
    Same journal

    Corneal Tissue Addition Keratoplasty for Keratoconus: Point-Counterpoint.

    Cornea·2026
    Same journal

    Posterior Segment Pressurization With Intravitreal Balanced Salt Solution to Stabilize Anterior Chamber Gas During Endothelial Keratoplasty.

    Cornea·2026
    Same journal

    Central Corneal Thickness Six Postoperative Months After DMEK or Triple-DMEK.

    Cornea·2026
    Same journal

    Rebubbling and Graft Detachment in Pre-Descemet Endothelial Keratoplasty: A Prospective Study.

    Cornea·2026
    Same journal

    Letter Regarding: ESCALÓN: A Prospective Randomized Trial of Corneal Endothelial Cell Therapy in Subjects With Corneal Edema.

    Cornea·2026
    See all related articles

    Area of Science:

    • Ophthalmology
    • Corneal Surgery
    • Refractive Surgery

    Background:

    • Homoplastic refractive surgeries like keratophakia involve freezing corneal tissue for a refractive lenticule.
    • Corneal tissue's high water content causes significant volumetric expansion upon freezing.
    • A standard 9.08% freezing increment is often assumed, rather than directly measured.

    Purpose of the Study:

    • To evaluate the actual increase in corneal tissue thickness after freezing in clinical keratophakia.
    • To compare refractive outcomes using assumed versus measured freezing increments.
    • To highlight the impact of freezing increment accuracy on refractive surgery results.

    Main Methods:

    • Analysis of 32 clinical keratophakia cases.
    • Direct measurement of corneal tissue thickness changes post-freezing.

    Related Experiment Videos

  • Calculation of residual refractive error (in diopters, D) based on actual and assumed freezing increments.

    • Main Results:

    • The average increase in corneal tissue thickness was 37% +/- 21%, significantly higher than the assumed 9.08%.
    • 16% of patients experienced a residual refractive error greater than 4 D when using measured increments.
    • Using the assumed 9.08% increment would have resulted in 28% of patients with >4 D error, with marked undercorrection in two-thirds.

    Conclusions:

    • The assumed 9.08% freezing increment is inaccurate for corneal tissue in refractive surgery.
    • Direct measurement of corneal tissue thickness during surgery is essential to avoid significant refractive inaccuracies.
    • Accurate measurement minimizes undercorrection and improves desired optical outcomes in homoplastic refractive procedures.