Clinical Trial: Biomechanics of Optic Neuropathy

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational

Official Title: Biomechanics of Optic Neuropathy

Brief Summary: The participant is being asked to be a subject in this research study because the participant may have a disorder that can cause optic nerve damage and impairment of his/her visual function which is called optic neuropathies (ON). Optic neuropathy refers to damage to the optic nerve (a "cable" connecting the eyes and the brain to transmit the visual signals) due to any cause.In this study, the investigator is using magnetic resonance imaging (MRI) and ophthalmic measures such as optic coherent tomography(OCT), which are non-invasive imaging tests to measure the changes in eye globe shape ,the flow of blood and brain fluid. It is hoped that this study will provide new knowledge that may allow the investigator to better understand the cause of symptoms associated with optic neuropathy and ways to better monitor what is happening.

Detailed Summary:
Sponsor: University of Miami

Current Primary Outcome: Globe deformation [ Time Frame: day 1 ]

Three measures of globe deformation are calculated by using the distance map: 1) optic nerve cupping(ONC), depicting the extent of the nerve head cupping; 2) posterior scleral bowing, depicting the degree of displacement of the posterior wall, and 3) maximal deformation (MD), depicting the combined deformation due to the displacement and the nerve cupping.


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Non-invasive magnetic resonance(MR) based intracranial pressure(MRICP) [ Time Frame: Day 1 ]
    The MR-based method for derivation of ICP utilizes the linear relationship between elastance and pressure to noninvasively estimate intracranial pressure from measurements of elastance. Elastance is estimated from the ratio of the maximal (systolic) volume and pressure changes that occur during the cardiac cycle. Volume change is determined from the momentary difference between volumes of blood and CSF entering and leaving the cranium during the cardiac cycle. The pressure change, i.e., the pulse pressure, is estimated from the CSF pulse pressure gradient. CSF pressure gradient is calculated using the Navier-Stokes relationship between derivatives of velocities and pressure gradients
  • Corneal thickness [ Time Frame: Day 1 ]
    Corneal thickness will be measured by corneal pachymetry. After anesthetic numbing drop is placed on the eye, blunt probe will briefly touch the participant's eye to obtain the measurement.
  • Visual field defect [ Time Frame: Day 1 ]
    Humphrey Field Analyzer II will be used to acquire the Mean deviation(MD).


Original Secondary Outcome: Same as current

Information By: University of Miami

Dates:
Date Received: August 28, 2016
Date Started: September 2016
Date Completion: September 2020
Last Updated: November 30, 2016
Last Verified: November 2016