Clinical trial NCT04439552: fMRI and IVCM Cornea Microscopy of CXL in Keratoconus
Official title: Neuroplasticity of Pain Pathways and Corneal Afferent Regeneration Following Corneal Crosslinking (CXL) in Keratoconus
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Pain, Postoperative
Pain, Chronic
Pain, Acute
Surgical Injury
Surgical Wound
Cornea Injury
Cornea
Keratoconus
Keywords: fMRI
Corneal Microscopy
IVCM
Neuroimaging
Lead sponsor: Boston Children's Hospital
Sponsor class: OTHER
First posted: 2020-06-19
Enrollment: 60
Sex: ALL
Minimum age (years): 8
Maximum age (years): 35
Standard ages: CHILD
ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: The population under study are patients with keratoconus who are undergoing a corneal cross-linking (CXL) procedure. Keratoconus is an eye condition where the cornea progressively develops abnormally into a cone shape, which can lead to distorted vision and irreversible vision loss The CXL procedure is designed to restore and maintain the shape of the cornea to avoid these complications.

Brief summary: Evaluation of neuroplasticity of pain pathways and corneal afferent nerve regeneration following corneal crosslinking (CXL) in keratoconus patients using fMRI and corneal In Vivo Confocal Microscopy (IVCM).

Detailed description: Our long-term goal is to evaluate the transition from acute to chronic pain that sometimes occurs following CXL in keratoconus patients. This study will determine whether these changes can be structurally and functionally quantified using functional neuroimaging and in vivo corneal microscopy (IVCM), and whether they can be predicted based on predisposing biological and psychological factors. Our central hypothesis is that CXL produces acute pain through activation of trigeminal afferents, and that post-operative chronic pain outcomes are related to neuroplastic changes in trigeminal circuitry, corneal afferent regeneration, and psychological factors.

Eligibility criteria: Inclusion Criteria:

CXL Group

* Age 8-35 years
* Clinical diagnosis of keratoconus and seeking CXL treatment
* English speaking ability sufficient to comprehend consent with parental assistance
* MRI compatible
* Ability to lie still for an MRI session (60 minutes)

Control Group

* Age 8-35 years
* No diagnosis of keratoconus
* English speaking ability sufficient to comprehend consent with parental assistance
* MRI compatible
* Ability to lie still for an MRI session (60 minutes)

Exclusion Criteria (Both Groups):

* Claustrophobic
* Weight \> 285 lbs (weight limit of the MRI table)
* Significant medical history, including:

Current DSM-IV-TR axis I psychiatric disorders. Chronic pain Significant head injury Seizures Brain tumor Cerebrovascular accident Neurological disease aside from migraine HIV-AIDs Prescription medication strongly implicated in causing dry eyes

* Magnetic implants or metal-containing tattoos on their chest or above
* Pregnancy
* History of contact lens wear
* Any allergic response to a numbing eyedrop in the past

Primary outcomes:
measure: Neural activity related to pain.
timeFrame: 1 year
measure: Corneal nerve morphology.
timeFrame: 1 year
Secondary outcomes:
Other outcomes:
Locations:
city: Boston
country: United States
facility: Boston Children's Hospital
state: Massachusetts
Study officials:
affiliation: Boston Children's Hospital
name: Eric A Moulton, OD PhD
role: PRINCIPAL_INVESTIGATOR
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