Understanding of the biomechanics accommodative apparatus in eyes with different refraction is important for solving problems theoretical and practical ophthalmology. Purpose: To determine changes anterior eye segment dimensions during accommodation response normal patients myopia, hypermetropia. Methods Material: 116 (56 aged from 18 to 30 years, -2.0 + 2.0 D) were examined. All underwent a fu...

Purpose. To evaluate correlation between tomographic gradation of keratoconus (KC) and its corresponding air-puff induced biomechanical response. Methods. Corneal tomography and biomechanics were measured with Scheimpflug imaging in 44 normal and 92 KC corneas. Deformation waveform was also analyzed with Fourier series. A custom KC severity scale was used from 1 to 3 with 3 as the most severe g...

PURPOSE To study the distribution and predominant orientations of fibrillar collagen at different depths throughout the entire thickness of the human cornea. This information will form the basis of a full three-dimensional reconstruction of the preferred orientations of corneal lamellae. METHODS Femtosecond laser technology was used to delaminate the central zones of five human corneas into t...

Second harmonic generation (SHG) is a well-established optical modality widely used in biomedical optics to image collagen based tissues. The coherent signal of the forward direction SHG produces a high resolution image that can resolve individual fibers (groups of fibrils). In highly ordered collagen lamellae, such as in the corneal stroma, it is important to determine the orientation of the f...

PURPOSE To quantify long-term changes in stromal collagen ultrastructure following penetrating keratoplasty (PK), and evaluate their possible implications for corneal biomechanics. METHODS A pair of 16 mm post-mortem corneo-scleral buttons was obtained from a patient receiving bilateral penetrating keratoplasty 12 (left)/28 (right) years previously. Small-angle x-ray scattering quantified col...

PURPOSE The aim of this study was to compare the changes in corneal biomechanical properties following small-incision lenticule extraction (SMILE) versus Q-value-guided femtosecond laser-assisted in situ keratomileusis (Q-FS-LASIK). METHODS In this prospective comparative study, patients with a sphere plus cylinder measurement of less than -10.00 D and cylinder measurement of less than -5.00 ...