A New Morphovolumetric Classification Of Keratoconus Correlated With Visual Evolution (Retics 2021 Classification)

To report a new classification of keratoconus based on morphovolumetric analysis correlated with visual function along the evolution of keratoconus based on a large database of 4000 cases.

Multicentric study performed in the National Network of Cooperative Research in Ophthalmology (RETICS): Vissum Miranza Alicante, Spain, Centro Oftalmologia Barraquer, Hospital Ramón y Cajal, Hospital Universitaria de Murcia, Technical University of Cartagena

From a large database of over 4000 keratoconus cases, grouped according to the best corrected visual acuity with glasses accomplished with the eyes affected by the disease was made and studied with a morphovolumetric computational model, reported by our group. A correlation between the morphovolumetric characteristics of the keratoconus and the visual function was obtained. The correlation between the morphovolumetric evolution and the vision was completed. The classification of keratoconus based on the morphovolumetric evolution of the disease is proposed (RETICS 2021 classification).

Keratoconus was classified into 5 groups: Group 0 (forme fustre, 20/20 vision), Group 1 (confirmed keratoconus with visual acuity of 0.921), Group 2 (confirmed keratoconus with best corrected visual acuity of 0.8 to 0.6), Group 3 (keratoconus with best corrected visual acuity from 0.6-0.2) and Group 4 (<0.2). Cases with terminal stages or corneal opacities were excluded. Group 1 was correlated (M±SD) with a morphovolumetric profile of 24.1; SD: 1.46, Group 2 (23.9; SD: 1.2), Group 3 (23.87; SD: 1.52), Group 4 (23.74; SD: 1.8).

Keratoconus is an ectatic disease characterized by the progressive distortion of the cornea. Its characteristic thinning and irregularity is characterized by morphovolumetric analysis that has been confirmed in this study. It is defined per group of visual acuity which is the morphovolumetric profile of each group. This new classification (RETICS 2021) will be helpful to indicate different therapeutic procedures based on corneal remodelling as well as to evaluate the outcomes and benefits of these techniques on morphovolumetric changes associated to visual gains