Refractive Surgery in a Patient with Alport Syndrome. A Case Report.

The authors present a case of a thirty-eight-year-old patient with Alport syndrome. The patient had several ocular symptoms of the disease and has been treated for systemic problems in connection with Alport syndrome since he was fifteen years old. At that age the patient also underwent a kidney transplant in order to deal with renal insufficiency. To date, he still uses immunosuppressants and antihypertensives. Furthermore, the patient suffers from perceptive deafness. The patient visited our clinic in 2021 with a request to solve his high refractive error, in which the diopters were so high that it was not possible to place them in spectacles. The patient's best corrected visual acuity was 0.6 with -8.0sph/-4.0cyl/ax15 in the right eye and 0.7partim with -8.0sph/-4.0cyl/ax155 in the left eye. The autorefractometer values were -6.25sph/-6.75cyl/ax17 in the right eye and -6.75sph/-6.5cyl/ax155 in the left eye. During the eye examination we found a number of ocular manifestations that are typical of Alport syndrome. On the cornea there were opacities as a residue of corneal erosions, and at one of the following check-ups we also found a newly developed corneal erosion. Subsequently, we found an anterior lenticonus and incipient cataract. Upon performing OCT, a typical temporal macular atrophy was evident. Fundus examination in artificial mydriasis showed just a minimal manifestation of fleck retinopathy. Due to the clinical manifestation we decided to perform cataract surgery and implant a monofocal toric intraocular lens in both eyes. There were no complications during the operations, however the surgeon registered a non-standard structure of the lens capsule. The capsule was more fragile, and performing capsulorhexis was much more complicated. A week after the surgery, higher cylinder diopters were still present. A decrease of the higher diopters was noticeable one month after surgery. The time interval between the first operation and the second operation was one month. The patient was highly satisfied with result, and uncorrected visual acuity improved by over four lines. After surgery the patient needed low diopters for near as well as far distance. In the case of this patient, the ocular manifestations were detected and treated in adulthood. Nevertheless, early detection of ocular symptoms of Alport syndrome in young patients before renal failure could lead to timely start of the treatment and delay a possible renal transplant. In case of any suspicion of Alport syndrome it is advised to send the patient to a pediatrician, and at an older age to an internal medicine specialist, for further examination.

Correlation Between Vitreous Level of Angiogenic Growth Factors and Oxygen Saturation in Retinal Vessels in Diabetic Retinopathy.

Purpose: The aim of this study was to investigate whether there is any association between the levels of the angiogenic growth factors and the vascular oxygen saturation in eyes with diabetic retinopathy. Methods: The study was designed as a prospective trial. The cohort consisted of 29 diabetic patients with scheduled vitreous procedures (intravitreal injection or pars plana vitrectomy). The control group included 30 patients scheduled for macular surgery (macular hole or epiretinal membrane). Nine patients (four from the diabetic maculopathy [DM] group and five from the control group) were excluded from the study because of unsuccessful vitreous samples. Retinal oximetry was performed several hours before the vitreous procedure was performed, and vitreous samples were obtained during the procedure. The concentrations of VEGF, Serpin F1/pigment epithelium-derived factor (PEDF), and placental growth factor (PlGF) were measured by ELISA. Results: A negative correlation between level of VEGF and arteriovenous (AV) saturation difference was determined in the DM group (Pearson correlation coefficient r = -0.607; two-tailed test, P = 0.002). Also a negative correlation between level of PlGF and AV saturation difference was determined in the DM group (Pearson correlation coefficient r = -0.521; two-tailed test, P = 0.011) A positive correlation between PlGF level and the vein saturation was not statistically significant (Pearson correlation coefficient r = 0.325; two-tailed test, P = 0.130). We did not find any correlation between vitreous level of PEDF and vascular saturation within the DM group. Conclusions: Our findings in diabetic patients suggests a correlation between the intravitreal level of proangiogenic factors and the AV difference measured by retinal oximetry.

Myopic Correction with Iris-Fixated Phakic Intraocular Lenses: Twelve-Year Results.

PURPOSE: To evaluate a 12-year follow-up of myopic patients after iris-fixated phakic intraocular lenses (IF pIOLs) implantation. Setting. Ophthalmology Department, Military University Hospital in Prague (Czech Republic). DESIGN: Single-center retrospective cohort study. METHODS: We describe the results of a cohort study that included 85 eyes of 46 myopic patients who underwent implantation of Verisyse myopia, Veriflex, and Verisyse myopia toric (all Abbott Medical Optics, Inc.) intraocular lenses. Refractive functions and adverse events were assessed preoperatively, at 6 months, and 1, 2, 5, and 12 years after IF pIOL implantation. RESULTS: Mean spherical equivalent was measured as -9.37 ± 2.87 D, 0.14 ± 0.61 D, and -0.42 ± 1.08 D, preoperatively, at 6 months and 12 years postoperatively, respectively. There was a significant reduction in the cylinder after surgery. At 12 years postoperatively, 90% of eyes had uncorrected distance visual acuity (UDVA) of 20/40 and 64% of 20/20. The safety index was 1.10 for the whole postoperative follow-up period. We found cataract formation in 3 eyes (3.5%). The endothelial cells loss (EC loss) directly caused by IF pIOL implantation was 6.0%, 8.10%, 12.8%, and 11.9%, at 1, 2, 5, and 12 years, respectively. In our cohort, 95% of eyes lost a higher percentage of EC than would be expected from a physiological loss at 12 years postoperatively. We found a significant negative interaction between preoperative pachymetry and EC loss, indicating that the lower pachymetry leads to a faster decline in endothelial cells density (ECD). IF pIOL re-enclavation was found in 28% of eyes. 7% of subluxations were caused by trauma. The mean time of nontraumatic re-enclavation was 6 years postoperatively. CONCLUSIONS: The study confirmed the advantages of IF pIOL implantation due to rapid visual recovery and stable visual function over the 12-year follow-up and also showed the influence of lower corneal pachymetry regarding EC loss.

In Situ Variable-Temperature Scanning Tunneling Microscopy Studies of Graphene Growth Using Benzene on Pd(111).

Using a combination of in situ ultrahigh-vacuum variable-temperature scanning tunneling microscopy, ex situ Raman spectroscopy, and scanning electron microscopy, we investigated the growth of graphene using benzene on Pd(111) at temperatures up to 1100 K. Benzene adsorbs readily on Pd(111) at room temperature and forms an ordered superstructure upon annealing at 473 K. Exposure to benzene at 673 K enhances Pd step motion and yields primarily amorphous carbon upon cooling to room temperature. Monolayer graphene domains, 10-30 nm in size, appear during annealing this sample at 873 K. Dosing benzene at 1100 K results in graphene domains with varying degrees of crystallinity, while post-deposition annealing at 1100 K for 1200 s yields monolayer graphene domains larger than 150 × 150 nm2. Our results, which indicate that graphene growth on Pd(111) using benzene requires deposition/annealing temperatures higher than 673 K, are in striking contrast with the reported growth of graphene using benzene at temperatures as low as 373 K on relatively inert Cu surfaces.