Clinical trial NCT01868620: Non-inferiority Trial of Iontophoretic Corneal Collagen Crosslinking (CXL) Compared to Standard Corneal Collagen Crosslinking in Progressive Keratoconus.
Official title: Non-inferiority Trial of Iontophoretic Corneal Collagen Crosslinking (CXL) Compared to Standard Corneal Collagen Crosslinking in Progressive Keratoconus.
Study type: INTERVENTIONAL
Overall status: TERMINATED
Phase: NA
Conditions: Progressive Keratoconus
Keywords: Progressive keratoconus
standard CXL
iontophoretic CXL
keratometry
Lead sponsor: University Hospital, Toulouse
Sponsor class: OTHER
Collaborators: name: Sooft Italia
name: Centre de Référence National du Kératocône
First posted: 2013-06-04
Enrollment: 28
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The primary purpose of the protocol is to compare the current standard CXL with iontophoretic CXL to provide evidence in relation to the efficacy and safety in progressive keratoconus.

Corneal collagen crosslinking (CXL) is the first surgical procedure that appears to halt the progression of keratoconus. In the current standard CXL, the central corneal epithelium must be debrided to efficiently permeate the corneal stroma with riboflavin. The epithelium debridement can cause severe pain, infection and stromal haze. The study hypothesis is that iontophorese CXL is as effective as standard CXL to stabilize a progressive keratoconus.

Detailed description: Keratoconus is a common bilateral progressive corneal ecstatic disease causing visual impairment by inducing irregular astigmatism and corneal opacities. This disorder typically begins during teenage years, progresses until the age of 30 to 40 years and, in severe forms, may need a corneal transplantation. CXL has changed the natural evolution of keratoconus. It creates links between collagen fibrils in order to rigidify the corneal stroma and slow down the progression of keratoconus. The corneal stroma is soaked with a riboflavin solution before being exposed to ultraviolet-A radiation.

In the current standard CXL, the central corneal epithelium must be debrided to allow the penetration of riboflavin into the cornea with a risk of side effects, such as pain for the first two post-operative days, temporary loss of visual acuity during the first three months, and serious complications such as infection and stromal opacity due to corneal scarring.

Iontophoresis is a non invasive technique in which a weak electric current is used to enhance the penetration of riboflavin into the cornea. The iontophoresis technique could allow intrastromal riboflavin diffusion, while keeping the corneal epithelium on, combining the efficiency of the standard procedure without the side effects of epithelial debridement.

Eligibility criteria: Inclusion Criteria:

* Age ≥ 18 years old
* Corneal thickness ≥ 400 µm
* Progressive stage 1 to 3 keratoconus (Krumeich classification)

Exclusion Criteria:

* Corneal thickness \< 400µm
* Stage 4 keratoconus (Krumeich classification)
* Concomitant corneal disease
* History of corneal surgery

Primary outcomes:
measure: The main outcome parameter is the non-inferiority of iontophoretic CXL compared to standard CXL in progressive keratoconus
timeFrame: Outcome measure is assessed at 1 year.
Secondary outcomes:
measure: Comparison of minimum keratometry
timeFrame: 3 months
Other outcomes:
measure: Comparison of mean keratometry
timeFrame: At 1 year
measure: Comparison of postoperative pain and complications during the follow up
timeFrame: Outcome measure is assessed at 1 year and at 3 months
measure: Comparison of visual acuity
timeFrame: Outcome measure is assessed at 1 year and at 3 months
measure: Intraoperative comparison of corneal concentration of riboflavin
timeFrame: Outcome measure is assessed at 1 year and at 3 months
measure: Comparison of depth of treatment
timeFrame: Outcome measure is assessed at 1 year and at 3 months
measure: Comparison of biomechanical parameters
timeFrame: Outcome measure is assessed at 1 year and at 3 months
measure: Comparison of corneal thickness
timeFrame: Outcome measure is assessed at 1 year and at 3 months for the tomographic measurement.
Locations:
city: Toulouse
country: France
facility: University Hospital Toulouse
state: Midi-Pyrenees
Study officials:
name: François MALECAZE, MD, PhD
role: PRINCIPAL_INVESTIGATOR
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