fMRI and IVCM Cornea Microscopy of CXL in Keratoconus

Boston Children's Hospital

Status: Enrolling

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

Study type: Observational

Funder types: Other

Identifiers

NCT04439552

IRB-P00035185

Details and patient eligibility

About

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).

Full 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.

Enrollment: 60 estimated patients

Sex: All

Ages: 8 to 35 years old

Volunteers: Accepts Healthy Volunteers

Inclusion and exclusion 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

Trial design

60 participants in 2 patient groups

CXL group

Description:

Patients who are about to undergo a corneal cross-linking (CXL) surgery to treat keratoconus.

Control group

Description:

Healthy volunteers age and sex matched to the CXL group.