Clinical trial NCT03220529: A Study to Test the Potential of Brillouin Microscopy for Biomechanical Properties Measurements in Human Cornea
Official title: A Study to Test the Potential of Brillouin Microscopy for Biomechanical Properties Measurements in Human Cornea
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Pellucid Marginal Corneal Degeneration
Keratoconus
Keratectasia
Lead sponsor: Massachusetts General Hospital
Sponsor class: OTHER
Collaborators: name: Massachusetts Eye and Ear Infirmary
First posted: 2017-07-18
Enrollment: 85
Sex: ALL
Minimum age (years): 15
Maximum age (years): 75
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: DIAGNOSTIC

Brief summary: The purpose of this research study is to find out if the new Brillouin Ocular Scanner can measure the variation (difference) of the corneal elastic changes involved in the onset of corneal ectasia, induced by LASIK surgery and cornea collagen crosslinking (CXL) treatment. Ectasia refers to the thinning and bulging of the cornea and results in severe vision degradation (loss), which may occur because of a progressive disease (keratoconus) or because of LASIK surgery. It is believed that the structural weakening of the cornea plays a major role in developing ectasia. CXL is a treatment that is able to halt the progression of ectasia.

The Brillouin Ocular Scanner is a technique based on the principles used in the laser speed measuring of a car (radar gun). When laser light illuminates a moving sample, a portion of the light slightly changes color. In our body, e.g in eye and corneal tissue, very weak sound waves are naturally present and they can induce a similar color shift. Measuring this color shift with a sensitive light color meter (spectrometer), we will measure the sound speed in the tissue.


Eligibility criteria: Inclusion Criteria:

* Subjects with healthy cornea
* Patients with mild, moderate, or advanced keratoconus
* Subjects diagnosed with PMD
* Patients before and after LASK surgery
* Patients with keratoconus before and after collagen crosslinking treatment

Exclusion Criteria:

* Normal volunteer group: presbyopia and/or cataract
* Keratoconus subjects group: corneas with scars developed, received any ocular surgery, such as laser vision correction surgeries or CXL treatment
* Subjects diagnosed with PMD: excludes corneas received any ocular surgery, such as laser vision correction or CXL treatment
* Patients before and after LASK surgery Corneas received priori ocular surgeries, taking any ocular medications except season allergy medicine such as artificial tears

Primary outcomes:
measure: Brillouin frequency shift of corneal stroma
timeFrame: at time of measurement
measure: Change of Brillouin frequency shift from base line in corneas received LASIK surgery
timeFrame: 1 day and 4-8 weeks
measure: Change of Brillouin frequency shift from base line in corneas received crosslinking treatment
timeFrame: 3 days, 1 month, 3 months, 6 months
Secondary outcomes:
Other outcomes:
Locations:
city: Boston
country: United States
facility: Massachusetts Eye and Ear Infirmary
state: Massachusetts
city: Zurich
country: Switzerland
facility: Institute for Refractive and Ophthalmic Surgery
Study officials:
affiliation: Massachusetts General Hospital
name: Seok Hyun Yun, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Scarcelli G, Besner S, Pineda R, Kalout P, Yun SH. In vivo biomechanical mapping of normal and keratoconus corneas. JAMA Ophthalmol. 2015 Apr;133(4):480-2. doi: 10.1001/jamaophthalmol.2014.5641. No abstract available.
citation: Scarcelli G, Besner S, Pineda R, Yun SH. Biomechanical characterization of keratoconus corneas ex vivo with Brillouin microscopy. Invest Ophthalmol Vis Sci. 2014 Jun 17;55(7):4490-5. doi: 10.1167/iovs.14-14450.
citation: Scarcelli G, Pineda R, Yun SH. Brillouin optical microscopy for corneal biomechanics. Invest Ophthalmol Vis Sci. 2012 Jan 20;53(1):185-90. doi: 10.1167/iovs.11-8281.
citation: Scarcelli G, Polacheck WJ, Nia HT, Patel K, Grodzinsky AJ, Kamm RD, Yun SH. Noncontact three-dimensional mapping of intracellular hydromechanical properties by Brillouin microscopy. Nat Methods. 2015 Dec;12(12):1132-4. doi: 10.1038/nmeth.3616. Epub 2015 Oct 5.