FCD led to a change of corneal biomechanical properties. CH and CRF were significantly lower in FCD eyes than in normal eyes. IOP(cc) was significantly higher in FCD eyes than in control eyes. These values may be useful in addition to CCT when assessing corneal rigidity. Thus, FCD may cause an underestimation error in IOP measurement.

The application of 30-min UVA CXL treatment with riboflavin increased stiffness of the porcine corneal tissue. A 60-min UVA-radiated tissue presents lower stiffness than the 30-min treated tissue, showing a similar biomechanical behavior than the untreated corneas. A prolongation of the UVA irradiation time may cause structural weakening of the porcine corneas.

In the last decade, we have witnessed substantial progress in our understanding of corneal biomechanics and architecture. It is well known that diabetes is a systemic metabolic disease that causes chronic progressive damage in the main organs of the human body, including the eyeball. Although the main and most widely recognized ocular effect of diabetes is on the retina, the structure of the cornea (the outermost and transparent tissue of the eye) can also be affected by the poor glycemic control characterizing diabetes. The different corneal structures (epithelium, stroma, and endothelium) are affected by specific complications of diabetes. The development of new noninvasive diagnostic technologies has provided a better understanding of corneal tissue modifications. The objective of this review is to describe the advances in the knowledge of the corneal alterations that diabetes can induce.

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Purpose. To examine biomechanical parameters of the cornea in myopic eyes and their relationship with the degree of myopia in a western healthy population. Methods. Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann correlated intraocular pressure (IOP), and corneal compensated IOP (IOPcc) were measured using the ocular response analyzer (ORA) in 312 eyes of 177 Spanish subjects aged between 20 and 56 years. Refraction was expressed as spherical equivalent (SE), which ranged from 0 to −16.50 diopters (D) (mean: −3.88 ± 2.90 D). Subjects were divided into four groups according to their refractive status: group 1 or control group: emmetropia (−0.50 ≤ SE < 0.50); group 2: low myopia (−0.75 ≤ SE < 3.00 D); group 3: moderate myopia (−3.00 ≤ SE ≤ −6.00 D); and group 3: high myopia (SE greater than −6.00 D). We analyzed the relationship between corneal biomechanics measured with ORA and SE. Results. CH in the emmetropia, low myopia, moderate myopia, and high myopia groups was 11.13 ± 0.98, 11.49 ± 1.25, 10.52 ± 1.54, and 10.35 ± 1.33 mmHg, respectively. CH in the highly myopic group was significantly lower than that in the emmetropic group (P = 0.07) and low myopic group (P = 0.035); however, there were no differences with the moderate myopic group (P = 0.872). There were no statistically significant differences regarding IOP among the four groups (P > 0.05); nevertheless, IOPcc was significantly higher in the moderately myopic (15.47 ± 2.47 mmHg) and highly myopic (16.14 ± 2.59 mmHg) groups than in the emmetropia (15.15 ± 2.06 mmHg) and low myopia groups (14.53 ± 2.37 mmHg). No correlation between age and the measured parameters was found. CH and IOPcc were weakly but significantly correlated with SE (r = 0.171, P = 0.002 and r = −0.131, P = 0.021, resp.). Conclusions. Present study showed only a very weak, but significant, correlation between CH and refractive error, with CH being lower in both moderately and highly myopic eyes than that in the emmetropic and low myopic eyes. These changes in biomechanical properties of the cornea may have an impact on IOP measurement, increasing the risk of glaucoma.

Implantation of an apodized multifocal IOL seems to be a satisfactory alternative to monofocal pseudophakia in children with unilateral cataract.

The revision of some nomograms for limbal incisions to correct astigmatism, compared with the outcomes of numerical simulation, leads to common guidelines. Numerical simulation supplies theoretical outcomes that the clinician can take into account to decide the values of the parameters for the surgery, in addition to their clinical experience.

We report the case of a 14-year-old girl with multiple findings characteristic of Noonan's syndrome, including short stature, mild mental retardation, facial, skeletal and renal abnormalities. In addition, ophthalmic examination revealed a keratoconus in the left eye and a right optic disc coloboma. To date, only two cases of Noonan's syndrome with keratoconus have been reported, and this is the second case of this syndrome with optic disc coloboma. To our knowledge, this is the first report of Noonan's syndrome associated with unilateral keratoconus and contralateral optic disc coloboma. In view of the large number of patients with Noonan's syndrome reported to date and the rarity of these ocular abnormalities, it is most likely that this association is fortuitous. Ocular findings reported in patients with Noonan's syndrome are reviewed.