Eyelid Elasticity—Molecular Basis and Exploration of Stiffening Techniques

TITLE: Eyelid Elasticity—Molecular Basis and Exploration of Stiffening Techniques

INVESTIGATORS:

Andrea K. M. Ross (1)

Albert Y. Wu (1)

  1. Department of Ophthalmology

DATE: Wednesday, 7 June 2023

TIME: 1:30–3:00 PM

LOCATION: Conference Room X399, Medical School Office Building, 1265 Welch Road, Stanford, CA

ABSTRACT

The Data Studio Workshop brings together a biomedical investigator with a group of experts for an in-depth session to solicit advice about statistical and study design issues that arise while planning or conducting a research project. This week, the investigator(s) will discuss the following project with the group.

INTRODUCTION

Connective tissue disorders of the eyelid such as ectropion, entropion, and Floppy Eyelid Syndrome have a high prevalence in the general population. Patients suffer from chronic eye irritation and inflammation, and corneal scarring is associated with vision loss and the risk of blindness. Eyelid laxity is based on age-related collagen and elastin degradation in the tarsal plate. These conditions are commonly treated with surgery as less invasive therapy options are limited. We aim to characterize the biomechanical properties of the eyelid and its associated connective tissue. Further, we intend to explore alternative and less invasive techniques to stiffen the affected tissues. Riboflavin-based UVA crosslinking therapy is the clinically established standard treatment for halting disease progression of keratoconus and other corneal ectasias. The conventional Dresden protocol was introduced by Wollensak et al. and consists of UVA-light irradiation with a wavelength of 370 nm and a power of 3 mW/cm2 for 30 minutes to the de-epithelialized cornea. First laboratory attempts have shown a promising stiffening effect in other collagenous tissues such as the tarsal plate.

HYPOTHESIS & AIM

We intend to investigate the biomechanical effect of various crosslinking protocols on the tarsal plate ex vivo and subsequently transition the ex vivo crosslinking technique to an in vivo approach. This represents the decisive step towards establishing a new alternative and non-invasive treatment method for eyelid laxity syndromes. Regarding this study question, we additionally aim to analyze different pathways of riboflavin penetration into the tarsal plate. Further, we will study the biomechanical effect of banking/storage of tarsal plate in different media.

PLANNED EXPERIMENTS

The following individual projects will be conducted:

  1. Tarsal Plate Banking
  2. Riboflavin Penetration of Tarsal Plate
  3. Tarsal Plate Crosslinking – ex vivo
    1. Part I (Aim: Determine best protocol based on previous study results in literature)
    2. Part II (Aim: Narrow down intensity intervals to determine best protocol from Part I)
    3. Part III (Aim: Does the Bunsen law of reciprocity apply for tarsal plate crosslinking?)
  4. Tarsal Plate Crosslinking – in vivo

STATISTICAL MODELS

We aim to determine the most effective procedure (banking method, riboflavin penetration, CXL procedure) for all individual experiments. Therefore, we are searching for suitable statistical tests to compare the results between the different study groups. Further, we would like to discuss adequate group sizes in order to calculate the tissues needed in advance.

STATISTICAL QUESTIONS

(1) What are adequate group sizes for each individual project?

(2) How should we perform the statistical evaluation regarding statistical tests (and models)?

ZOOM MEETING INFORMATION

Join from PC, Mac, Linux, iOS or Android:

https://stanford.zoom.us/j/91706399349?pwd=UXFlclNkakpmZC9WVWwrK244T2FwUT09

Password: 130209

Or iPhone one-tap (US Toll):

+18333021536,,91706399349# or

+16507249799,,91706399349#

Or Telephone:

Dial:  +1 650 724 9799 (US, Canada, Caribbean Toll) or

+1 833 302 1536 (US, Canada, Caribbean Toll Free)

 

Meeting ID: 917 0639 9349

Password: 130209

International numbers available: https://stanford.zoom.us/u/abKRNREFBK

Meeting ID: 917 0639 9349

Password: 130209

SIP: 91706399349@zoomcrc.com