Clinical trial NCT05114928: Correlation Between Q-value Changes and Progression of Pediatric Keratoconus.
Official title: Correlation Between Changes in Corneal Asphericity and Progression of Keratoconus in Children
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Keratoconus
Collagen Diseases
Corneal Disease
Keywords: corneal asphericity
corneal collagen cross-linking
Q-value
Pediatric keratoconus
Trans-epithelial
Lead sponsor: Benha University
Sponsor class: OTHER
First posted: 2021-11-10
Enrollment: 9
Sex: ALL
Minimum age (years): 6
Maximum age (years): 16
Standard ages: CHILD
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: RETROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: This retrospective observational study was performed at Ophthalmology department, Benha University, EGYPT using the medical records of 9 children diagnosed as bilateral progressive KC that was confirmed by Pentacam according to amsler criteria, patients had undergone bilateral TE-CXL in the period from January 2016 to August 2016 and completed annual visits till 5 years of follow-up.

Brief summary: Keratoconus is a progressive corneal disease characterized by asymmetric corneal thinning and structural changes in corneal collagen which leads to decrease in visual acuity due to myopic shift, irregular astigmatism or corneal scarring. Early detection of the disease in children aids in halting the progression and improve their quality of life. There is no consensus regarding the progression criteria of the disease, we aimed to assess the changes in corneal asphericity in children after corneal collagen crosslinking and investigate any possible correlation with progression criteria widely used.

Detailed description: The Keratoconus progression is defined as increasing by 1.0 diopter (D) or more in the maximum keratometry (Kmax), progressive deterioration in Minimal Corneal Thickness is also associated with KC progression, other methods have been investigated to confirm KC progression such as changes in manifest refraction, unaided visual acuity (UAVA), BCVA, posterior keratometric data and higher order aberrations (HOA) which are altered in KC and can aid to confirm disease progression. Q-value (a coefficient of corneal asphericity) reflects the shape of the cornea, its refractive power, and spherical aberration. The mean Q-value in normal cornea is -0.26 ± 0.18, the severity of KC and the Q-value are inversely related.

Mean Q-value in KC at 8mm zone is -0.84 and -1.10 for anterior and posterior corneal surfaces, respectively. Until now, no precise criteria of KC progression especially in cases had undergone previous trans-epithelial corneal collagen cross-linking (TE-CXL) to halt the progression of the disease. In the present study we aimed to analyze the correlation between the changes in Q-value and progression of the KC in children had undergone bilateral TE-CXL.

Eligibility criteria: Inclusion Criteria:

Children that were diagnosed as bilateral progressive KC (stage I-III, according to amsler classification, Kmax change \>1D between 2 scanning with at least 2 months apart), and their age were less than 16 years old at time of TE-CXL, topographic parameters were Kmax 47-60D and MCT more than 400μm.

Exclusion Criteria:

Eyes with central corneal scarring, amblyopic eyes, and other corneal pathologies that may alter Pentacam scanning.

Primary outcomes:
measure: Changes in corneal asphericity (Q-value) in all subjects.
timeFrame: Baseline and annually after TE-CXL till 5 years of follow-up
Secondary outcomes:
measure: Correlation between Q-value changes and disease progression in both groups.
timeFrame: Baseline and annually after TE-CXL till 5 years of follow-up
measure: The Q-value as a predictive value in keratoconus progression.
timeFrame: Baseline and annually after TE-CXL till 5 years of follow-up
Other outcomes:
Locations:
city: Banhā
country: Egypt
facility: Ahmed Abdelshafy Tabl
state: Benha
Study officials:
affiliation: Benha University
name: Ahmed A Tabl, MD
role: PRINCIPAL_INVESTIGATOR
References: