fMRI and IVCM Cornea Microscopy of CXL in Keratoconus

Recruiting

• Conditions: Pain, Chronic; Pain, Postoperative; Pain, Acute; Cornea; Keratoconus; Surgical Injury; Surgical Wound; Cornea Injury

• Registration Number: NCT04439552
• Lead Sponsor: Boston Children's Hospital

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.

Study Timeline

• Study First Submitted: 2020-06-17
• Study First Submitted QC: 2020-06-17
• Study First Posted: 2020-06-19
• Study Start: 2021-10-04
• Status Verified: 2024-02
• Last Update Submitted: 2024-02-07
• Last Update Posted: 2024-02-08
• Primary Completion: 2025-08
• Study Completion: 2025-12

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 60

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

Exclusion Criteria

Not provided

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Neural activity related to pain.	1 year	Pain-related brain activation measured with fMRI.
Corneal nerve morphology.	1 year	Afferent nerve fiber morphology measured with IVCM.

Trial Locations

Locations (1)

Boston Children's Hospital; 🇺🇸 Boston, Massachusetts, United States