Validation Study on Eye Rubbing Questionnaire in Patients With or Suspected of Having a Keratoconus (KC) (QFK)

Validation Study on Eye Rubbing Questionnaire in Patients With or Suspected of Having a Keratoconus (KC)

Validation Study on Eye Rubbing Questionnaire in Patients With or Suspected of Having a Keratoconus (KC)

KC is a degenerative disorder of the cornea. Keratoconus etiopathogenesis remains unclear and may rely on environmental and genetic factors. Usually considered as a rare disease (<1/2000), but the prevalence is nowadays growing worldwide up to 1/500. In that pathology, cornea progressively gets thinner, and there is a deformation of the corneal surface which can induce high order optical aberrations and visual impairment. Eye rubbing is certainly the main factor in the progression or development of keratoconus (KC), yet it is only very partially evaluated and quantified in current management. Environmental and clinical factors will be collected and associated with a eye rubbing Questionnaire, specifically pointing out eye rubbing.

CNRK center is working on an eye rubbing questionnaire since 2017 in order to quantify that pejorative factor. Patient education can limit in a certain amount the Keratoconus progression. Thus, our objective will be to evaluate the therapeutic impact on Keratoconus progression of patient's education against eye rubbing according to an eye rubbing Questionnaire. The validation of a dedicated questionnaire is an important act that will allow the scientific evaluation of this factor with both environmental and behavioral traits. It can thus be integrated into our care activity for its intrinsic educational and therapeutic virtues and for its decision-making aid for certain treatments. It will be useful first of all for the refinement of the correct prescription of corneal collagen crosslinking for evolving KC or KC with a high risk of progression.

eye rubbing questionnaire at baseline and 15 days later for exploratory phase; at baseline and at 6 month follow-up for confirmatory phase and at home

validation of our eye rubbing questionnaire will be made through the evaluation of its Suitability (Appearance validity, Content validity), Reliability (Consistency and homogeneity, Reproducibility), Applicability (Feasibility and acceptability), Validity (Construct validity), Sensitivity (Sensitivity to change, Discriminative validity)

The evolution of the answers to the questionnaire and of the disease between the visit to M0 and the visit at 6 months will be defined by: A decrease of at least one level in the intensity, or duration, or frequency of eye rubbing Stopping eye rubbing

The clinical course being determined as follows: Increase in maximum anterior or posterior keratometry (corneal curvature) of more than 1 diopter (D), or Corneal thinning at the thinnest point of the cornea (CTP) of more than 10 microns

Estimate the scalability of the KC at 6 months for each of the rubbing categories (reduction of rubbing or not, cessation of rubbing or not)

Inclusion Criteria: Coming for the first time for expert advice on KC Having a suspected or known KC Being over 13 years old (or from 13 years old) Possess computer connection equipment (computer, tablet or smartphone) and access to the network, for the completion of the questionnaire at home. Being affiliated to or beneficiary of health insurance Have signed the informed consent form from the patient and from legal representatives for minor patient Exclusion Criteria: Being incapacitated or unable to follow study procedures Patient under legal protection