Higher Irradiance in Keratoconus Ectasia

Stephen Trokel

Status: Withdrawn

Conditions: Ectasia; Keratoconus

Treatments: Drug: Riboflavin 0.1% ophthalmic solution; Device: UVA Light with irradiance exposure of 9 mW/cm2

Study type: Interventional

Funder types: Other

Identifiers

NCT01789333

AAAF4157

Details and patient eligibility

About

The purpose of the study is to see if brighter lights will allow for shortening of the treatment time required to stabilize the eyes of patients with keratoconus or a bulging cornea. The investigators will be comparing the therapeutic effects of two different higher brightnesses of ultra violet light on a riboflavin treated eye. One light will be twice as bright as the other and the exposure time of these brighter lights to deliver equivalent energy to the cornea will be reduced from the standard 30 minutes to 10 and 5 minutes. Riboflavin is vitamin B2 and the investigators are trying to determine if an identical clinical effect can be achieved the brighter treatment lights are used for shorter times. The investigators will also monitor the clinical effect and the status of the cornea to see if additional risks are associated with the brighter light.

Sex: All

Ages: 16+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

Subjects who have one or both eyes that meet two of the following criteria will be considered candidates for this study:

1. 16 years of age or older

2. Having a diagnosis of progressive keratoconus or pellucid marginal degeneration.

   1. Characteristic pattern of deformity as analyzed by the Pentacam map.
   2. Minimal thickness of 350 microns

3. The ability to sign a written informed consent

4. States a willingness and ability to comply with schedule for follow-up visits

5. Subject willing to remove contact lenses prior to evaluation and treatment

Inclusion criteria for ectasia

1. History of having undergone a keratorefractive procedure and show:

   1. Steepening by Pentacam study
   2. Thinning of cornea
   3. Shift in the position of thinnest portion of cornea
   4. Unstable refraction with increasing myopia and astigmatism
   5. Development of irregular astigmatism

2. At least two of the above criteria must be present.

Exclusion criteria

Subjects meeting any of the following criteria will be excluded from this study:

Subjects meeting any of the following criteria will be excluded from this protocol:

1. Eyes classified as either normal or atypical normal,
2. Corneal pachymetry ≤ 350 microns at the thinnest point in treatment zone measured by Pentacam.
3. A history of delayed epithelial healing.
4. Pregnancy (including plan to become pregnant) or lactation during the course of the study
5. A known sensitivity to study medications
6. Patients with nystagmus or any other condition that is severe enough to prevent steady gaze during the treatment
7. Inability to cooperate with diagnostic tests.
8. Patients with a current condition that, in the investigator's opinion, would interfere with or prolong epithelial healing.
9. Patients who are unable to remain supine and tolerate a lid speculum.

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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0 participants in 1 patient group

9 mw/cm2 at 10 minutes group

Experimental group

Description:

30 patients will be treated with UVA light source at 9 mw/cm2 at 10 minutes. Drug: Riboflavin Dose:1 drop every 2 to 3 minutes for 15 to 20 minutes

Treatment:

Device: UVA Light with irradiance exposure of 9 mW/cm2

Drug: Riboflavin 0.1% ophthalmic solution