Topographic Outcomes in Keratoconus Surgery: Epi-on versus Epi-off Iontophoresis Corneal Collagen Cross-Linking.

Background: Corneal collagen cross-linking (CXL) has become the gold standard for mild and moderate stages to stop the progression of keratoconus. We analyzed some corneal topography indices to compare iontophoresis epi-on and iontophoresis epi-off techniques throughout a two-year follow-up. Methods: A total of 64 eyes of 49 patients who underwent CXL were recruited. In 30 eyes the epi-off technique was performed, whereas the remaining 34 eyes were treated with the epi-on technique. All patients underwent a complete ophthalmologic examination that included CDVA, central and thinnest corneal thickness, Schirmer test I, TBUT test, and the Ocular Surface Disease Index. Results: In both groups, a significant improvement in visual function was recorded. No statistically significant differences between Kmax, Mean K, Flat K, Steep K values were found. Statistically significant differences (p < 0.05) between the epi-on and epi-off groups' pachymetry before and after 24 months follow-up as well as between the epi-on and epi-off groups' topographically thinnest point in the immediate post-surgery and 24 months after surgery were recorded. Conclusion: Our study highlighted that both techniques are valid in mid-term corneal stabilization. The advantage of the new iontophoresis epi-off cross-linking technique could be found in a faster imbibing time of the cornea, therefore reducing surgical times, with a lower risk of complications.

Predicting the early visual outcomes in sellar-suprasellar lesions compressing the chiasm: the role of SD-OCT series of 20 patients operated via endoscopic endonasal approach.

BACKGROUND: Tumors involving the sellar area often cause visual disorders due to optic nerves/chiasm compression, so that surgery is required. However, the likelihood of visual improvement/restoration is variable. Optical coherence tomography (OCT) is a valid diagnostic tool for defining pathological conditions of the optic apparatus. We herein investigated the role of the SD-OCT and the best corrected visual acuity in predicting postoperative visual recovery, in patients complaining of chiasm compression due to sellar-suprasellar lesions. METHODS: We retrospectively analyzed 20 patients (7 females and 13 males; mean age 50.8±17.87 years, range 11-83), with optic chiasm/nerve compression that underwent endoscopic endonasal approach at the Division of Neurosurgery of the University of Naples Federico II, Naples, Italy, between June 2014 and February 2015. Preoperative ophthalmological assessment focused on BCVA Snellen charts, standard automated perimetry test and SD-OCT. Test were repeated at two weeks, one and three months after surgery. RESULTS: A significant thickness reduction in all the patients, as compared to the control group was noted: GCC thickness reduction remained mostly unchanged postoperatively: 42.9% of the patients had altered visual acuity (VA), while the Perimetry revealed 90% of altered preoperative MD values (MD>-2.00): perimetry improvement was noted in 93% of cases and visual acuity in 91.3% of cases. A direct correlation between preoperative retinal status and functional recovery was identified considering the values of pRNFL and GCC. CONCLUSIONS: OCT provides valuable information regarding the entity of compression also in patients without any visual field defects. Although several factors should be taken into consideration, we retain that preoperative RNFL and GCC thickness values can be claimed as a reliable predictor of visual recovery in those patients presenting chiasm compression.

Early vascular modifications after endoscopic endonasal pituitary surgery: The role of OCT-angiography.

PURPOSE: The aim of the present study is to analyze the changes in retinal vessel density (VD), using Optical Coherence Tomography Angiography (OCT-A), in patients that received endoscopic endonasal approach for the removal of an intra-suprasellar pituitary adenoma compressing optic chiasm. METHODS: We evaluated the VD in Superficial Capillary Plexus (SCP), Deep Capillary Plexus (DCP), Radial Peripapillary Capillary (RPC) and the Foveal Avascular Zone (FAZ) area in a series of fourteen patients (7 males, 7 females, mean age 56 ± 13 years), as compared to healthy controls. We also detected the structural Spectral Domain (SD)-OCT parameters: Ganglion Cell Complex (GCC), Retinal Nerve Fiber Layer (RNFL), visual field parameters (Mean Deviation, Pattern Standard Deviation) and Best Corrected Visual Acuity (BCVA). These measurements were performed prior than surgery and 48 hours after. RESULTS: The patients showed a significant decrease in VD of the macular and papillary regions, a significant increase in FAZ area, a significant impairment in SD-OCT, VF parameters and BCVA respect to 14 eyes of 14 healthy controls (p<0.05), at pre-op evaluation. In patients group the VD in SCP, DCP and RPC increased after surgery respect to baseline but the difference turned to be out statistically significant only in RPC (p = 0.003). Also the BCVA (p = 0.040) and the Mean Deviation at visual field (p = 0.015) significantly improved after surgery. While there was a reduction in structural OCT parameters but it was statistically significant only in GCC (p = 0.039). A positive correlation was found between the preoperative VD of the RPC, Mean Deviation, BCVA and the postoperative Mean Deviation (r = 0.426 p = 0.027; r = 0.624 p = 0.001; r = 0.515 p = 0.006). CONCLUSION: OCT-A allows to detect the early changes occurring within 48 hours after surgery showing that the improvement in retinal vessel density could occur before the recovery of the structural OCT parameters and can be a positive predictive factor for the functional recovery.

Peripapillary Vessel Density as Early Biomarker in Multiple Sclerosis.

Background: To evaluate retinal vessel density (VD) in macular and in peripapillary regions in patients with recent onset of multiple sclerosis, at initial demyelinating event (IDE) and in matched relapsing-remitting multiple sclerosis (RRMS) patients. Methods: We evaluated VD in superficial capillary plexus, deep capillary plexus, choriocapillaris and radial peripapillary capillary plexus in IDE, RRMS patients and in matched healthy controls (HCs) through Optical Coherence Tomography Angiography (OCT-A). Clinical history, including history of optic neuritis, Expanded Disability Status scale and disease duration of patients were collected. Results: Thirty patients (20 with IDE and 10 with RRMS) and 15 HCs were enrolled. IDE patients showed a lower VD in radial peripapillary capillary plexus compared with controls (coeff. ß = -3.578; p = 0.002). RRMS patients displayed a lower VD in both superficial capillary plexus and radial peripapillary capillary plexus compared with HCs (coeff. ß = -4.955; p = 0.002, and coeff. ß = -7.446; p < 0.001, respectively). Furthermore, RRMS patients showed a decreased VD in radial peripapillary capillary plexus compared with IDE patients (coeff. ß = -3.868; p = 0.003). Conclusions: Peripapillary region vessel density reduction, revealed through OCT-A, might be considered as an early event in MS, and might be relevant as a biomarker of disease pathology.