To evaluate long-term keratoconus stability after corneal crosslinking (CXL) with riboflavin. In this prospective study, 57 eyes of 55 patients with progressive keratoconus, consecutively treated with ultraviolet A (UVA) - riboflavin CXL, were examined with the corneal topographer Pentacam, the biometer IOLMaster and the analyzer of corneal biomechanics Ocular Response Analyzer before and during a 24 months follow-up after CXL. Twenty-four months after CXL, there was a significant improvement in best corrected visual acuity (BCVA) (P<0.01), a significant decrease in corneal thinnest point (CTP), keratometry readings at the keratoconus apex (K max), and corneal volume (CV) (P<0.01), and a significant increase in axial eye length (AL) (P=0.01). No significant changes in anterior chamber volume (ACV) and depth (ACD), (P=0.8), corneal hysteresis (CH) (P=0.16) and corneal resistance factor (CRF) (P=0.06) were found. However, in the subgroup of patients with decreased K max readings 24 months after treatment, both CH and CRF showed a significant reduction (P<0.01). In the first month after the procedure, CXL induces a reduction in corneal volume. During the 24 months follow-up the cornea tends to recover its original volume with a persistence of the CXL efficacy.

Objective: To investigate functional connectivity of the visual resting-state network (V-RSN) in normal-sighted relapsing-remitting multiple sclerosis (RRMS) patients with and without previous optic neuritis (ON). Methods: Thirty normal-sighted RRMS patients, 16 without (nON-MS) and 14 with (ON-MS) previous ON, and 15 age- and sex-matched healthy controls (HCs) underwent a neuro-ophthalmologic evaluation, including automated perimetry and retinal nerve fiber layer (RNFL) measurement, as well as an MRI protocol, including structural and resting-state fMRI (RS-fMRI) sequences. Functional connectivity of the V-RSN was evaluated by independent component analysis (ICA). Regional gray matter atrophy was assessed by voxel-based morphometry (VBM). A correlation analysis was performed between RS-fMRI results and clinical, neuro-ophthalmologic, and structural MRI variables. Results: Compared to HCs, patients with RRMS showed a reduced functional connectivity in the peristriate visual cortex, bilaterally. Compared to nON-MS, ON-MS patients revealed a region of stronger functional connectivity in the extrastriate cortex, at the level of right lateral middle occipital gyrus, as well as a region of reduced functional connectivity at the level of right inferior peristriate cortex. These latter changes correlated with the number of previous ON. All detected V-RSN changes did not colocalize with regional gray matter atrophy. Conclusions: Normal-sighted RRMS patients show a significant functional disconnection in the V-RSN. RRMS patients recovered from a previous ON show a complex reorganization of the V-RSN, including an increased functional connectivity at the level of extrastriate visual areas.

The number of implants needed to support a maxillary overdenture is still a controversial issue. The aim of this systematic review was to investigate the number of implants required to support a maxillary overdenture in order to obtain optimal treatment outcomes in terms of implant survival, overdenture longevity and patient satisfaction. Pubmed and EMBASE databes were systematically searched and complemented by hand searching from 2000 to 2017. The Prisma statement and a PICOS approach were adopted. All selected articles provided at least two-year follow-up and 10 totally edentulous patients. Survival rate of implants and overdentures were statistically analyzed according to number of implants and according to splitting technique, employing non-parametric Fisher Test for unpaired data. For the pooled analysis of implant failures, the odds ratio between group of 4 splinted implants and group of more than 4 splinted was calculated. A total of 28 articles were included. Data analysis of the included studies showed that the survival rate of implants appeared higher in ≥ 4 implants group, whereas the high survival rate of overdentures and patient satisfaction were not significantly influenced by the number of implants. The findings of our analysis indicate that overall the most frequent tendency is to place at least four implants, splinted or unsplinted, in order to ensure a higher survival rate of implants. However, the relationship between overdenture survival, the patient's quality of life, and the number of implants required to support a maxillary overdenture has yet to be clarified.

To evaluate the relationship between corneal hysteresis (CH) and corneal resistance factor (CRF) with age, central corneal thickness (CCT), corneal curvature (KM), corneal volume (CV), and refractive error in naïve eyes. 105 healthy subjects (58 male and 47 female) were included in this study. The ages ranged from 19 to 82 years (mean 43.1 ± 15.4 years) and refraction between -11 D and +6 D (mean -0.79 ± 2.95 D). CH and CRF obtained with the Ocular Response Analyzer (ORA) were correlated with age, refractive error, Goldmann Applanation Tonometry (GAT), and with CCT, KM, CV obtained with the Pentacam, and with Corneal-Compensated Intraocular Pressure (IOPcc) and Goldmann-correlated intraocular pressure measurement (IOPg) obtained with ORA. A multivariable mixed effect model was used to evaluate associations among these parameters. CH ranged from 6.9 to 14.6 mmHg (mean 10.26 ± 1.49 mmHg); CRF ranged from 5.8 to 17 mmHg (mean 10.38 ± 1.64 mmHg). Multivariate analysis showed a statistically significant correlation between CH with CCT (p < 0.001), and KM (p < 0.001), and between CRF with CCT (p < 0.001) and GAT (p < 0.001). Our findings support the hypothesis that CH and CRF are related to the corneal shape and thickness, and show a decrease of CH with age.