1 / 11

Corneal Biomechanical Assessment using Dynamic Ultra High-Speed (UHS) Scheimpflug Imaging and Non-Contact Tonometry

Corneal Biomechanical Assessment using Dynamic Ultra High-Speed (UHS) Scheimpflug Imaging and Non-Contact Tonometry (NCT) . Diogo L. Caldas, MD Isaac C. Ramos, MD Renato Ambrósio Jr, MD, PhD Michael W. Belin, MD, FACS Cynthia J. Roberts, PhD.

yvon
Download Presentation

Corneal Biomechanical Assessment using Dynamic Ultra High-Speed (UHS) Scheimpflug Imaging and Non-Contact Tonometry

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Corneal Biomechanical Assessment using Dynamic Ultra High-Speed (UHS) Scheimpflug Imaging and Non-Contact Tonometry (NCT) Diogo L. Caldas, MD Isaac C. Ramos, MD Renato Ambrósio Jr, MD, PhD Michael W. Belin, MD, FACS Cynthia J. Roberts, PhD Dr. Ambrósio, Dr. Belin and Dr. Roberts are consultants for Oculus Optikgeräte GmbH (Wetzlar, Germany)

  2. Purpose • To present CorVis ST (Oculus, Wetzlar) - a new clinical tool for assessment of corneal biomechanical properties and intraocular pressure (IOP) • To test its capability to distinguish different materials based on their deformation characteristics Oculus CorVis ST • Ultra High-Speed (UHS ST) • Scheimpflug Technology: 4,330 frames/sec • 8mm horizontal coverage • NCT symmetrically metered air pulse

  3. Methods: Contact Lens Experiment • Three hydrophilic contact lenses: • TAN-40: 62% Hydroxyethylmethacrylate (525µm thick) • TAN-58: 42% Methylmethacrylate (258µm thick) • TAN-G5X: 41% Hydroxyethylmethacrylate/Glycolmethacrylate, (550µm thick) • Mounted on a water chamber with adjustable pressures

  4. Methods: Contact Lens Experiment • Pressures from 0 to 70mmHg (5mmHg intervals) • 6 measurements for each lens at each pressure level MAIN OUTCOME MEASURES • Deformation amplitude (DA- highest concavity displacement of the apex) • Corneal speed and curvature • Time for the highest concavity momentum • Curvature at highest concavity momentum

  5. Response is influenced by the Pressure at the Chamber Contact Lens Experiment TAN 40 at 0mmHg adjusted chamber pressure Contact Lens Experiment TAN 40 at 20mmHg adjusted chamber pressure Contact Lens Experiment TAN 40 at 60mmHg adjusted chamber pressure

  6. Deformation Amplitude X Pressure (hydrostatic head)

  7. Results: Deformation amplitude • DA: Highest concavity displacement of the apex Contact Lens Experiment Measurements at 20mmHg adjusted IOP Coef. Of Variability < 5%

  8. Response is influenced by the Pressure at the Chamber TAN 40 at 0mmHg adjusted chamber pressure TAN 58 at 60mmHg adjusted chamber pressure

  9. Results: Highest Concavity • Time of highest concavity momentum (HC Time) • Curvature at highest concavity momentum (Cur HC)

  10. Conclusions from Contact Lens Experiment • Dynamic UHS Scheimpflug corneal imaging with NCT enables to differentiate physical properties in test objects based on deformation response • The response is influenced by the material properties and by chamber pressure • The inspection of the actual deformation process provides further detailing for corneal characterization • Relevance for Cornea, Refractive Surgery, Glaucoma…

  11. Thank You ! diogolcaldas@gmail.com

More Related