Quantification of BNN27, a novel neuroprotective 17-spiroepoxy dehydroepiandrosterone derivative in the blood and retina of rodents, after single intraperitoneal administration.

BNN27 is a novel 17-spiroepoxy derivative of the neurosteroid Dehydroepiandrosterone with neuroprotective properties. The purpose of this study was the detection and quantification of BNN27 after single intraperitoneal administration, in the serum and retina of normal rodents. Forty-two C57BL/6 mice and 48 Sprague-Dawley rats were used for the quantification of BNN27 in the blood serum and retina, respectively. BNN27 was injected intraperitoneally (i.p.) at concentrations of 100 and 30 mg/kg of body weight (b.w.), respectively. The blood was collected with retro-orbital bleeding and the retina was isolated after enucleation at various time points. The molecule concentrations were measured with Liquid chromatography-mass spectrometry (LC-MS). Non-compartmental analysis was used to determine pharmacokinetic parameters. BNN27 was found to have an elimination constant kel  = 0.465 h-1 and mean residence time (MRT) 2.154 h in the mouse serum. The maximum concentration (Cmax ) in the retina was detected at 2 h ( tCmax ) after intraperitoneal administration and was equal to 1100 ng/g. BNN27 is rapidly eliminated from both blood and retina. In the retina specifically, it is undetectable 6 h after injection. BNN27 shows a rapid systemic elimination as anticipated by its small size and lipophilicity. It is measurable in small peripheral tissues such as the rat retina, after one single i.p. injection, using a simple method such as LC-MS. Its detection in the retina corroborates the existing biological data that the molecule crosses the blood-retinal barrier, highlighting it as a potential neuroprotective agent for retinal disease.

Mutations in CEP78 Cause Cone-Rod Dystrophy and Hearing Loss Associated with Primary-Cilia Defects.

Cone-rod degeneration (CRD) belongs to the disease spectrum of retinal degenerations, a group of hereditary disorders characterized by an extreme clinical and genetic heterogeneity. It mainly differentiates from other retinal dystrophies, and in particular from the more frequent disease retinitis pigmentosa, because cone photoreceptors degenerate at a higher rate than rod photoreceptors, causing severe deficiency of central vision. After exome analysis of a cohort of individuals with CRD, we identified biallelic mutations in the orphan gene CEP78 in three subjects from two families: one from Greece and another from Sweden. The Greek subject, from the island of Crete, was homozygous for the c.499+1G>T (IVS3+1G>T) mutation in intron 3. The Swedish subjects, two siblings, were compound heterozygotes for the nearby mutation c.499+5G>A (IVS3+5G>A) and for the frameshift-causing variant c.633delC (p.Trp212Glyfs(∗)18). In addition to CRD, these three individuals had hearing loss or hearing deficit. Immunostaining highlighted the presence of CEP78 in the inner segments of retinal photoreceptors, predominantly of cones, and at the base of the primary cilium of fibroblasts. Interaction studies also showed that CEP78 binds to FAM161A, another ciliary protein associated with retinal degeneration. Finally, analysis of skin fibroblasts derived from affected individuals revealed abnormal ciliary morphology, as compared to that of control cells. Altogether, our data strongly suggest that mutations in CEP78 cause a previously undescribed clinical entity of a ciliary nature characterized by blindness and deafness but clearly distinct from Usher syndrome, a condition for which visual impairment is due to retinitis pigmentosa.

Isolated and Syndromic Retinal Dystrophy Caused by Biallelic Mutations in RCBTB1, a Gene Implicated in Ubiquitination.

Inherited retinal dystrophies (iRDs) are a group of genetically and clinically heterogeneous conditions resulting from mutations in over 250 genes. Here, homozygosity mapping and whole-exome sequencing (WES) in a consanguineous family revealed a homozygous missense mutation, c.973C>T (p.His325Tyr), in RCBTB1. In affected individuals, it was found to segregate with retinitis pigmentosa (RP), goiter, primary ovarian insufficiency, and mild intellectual disability. Subsequent analysis of WES data in different cohorts uncovered four additional homozygous missense mutations in five unrelated families in whom iRD segregates with or without syndromic features. Ocular phenotypes ranged from typical RP starting in the second decade to chorioretinal dystrophy with a later age of onset. The five missense mutations affect highly conserved residues either in the sixth repeat of the RCC1 domain or in the BTB1 domain. A founder haplotype was identified for mutation c.919G>A (p.Val307Met), occurring in two families of Mediterranean origin. We showed ubiquitous mRNA expression of RCBTB1 and demonstrated predominant RCBTB1 localization in human inner retina. RCBTB1 was very recently shown to be involved in ubiquitination, more specifically as a CUL3 substrate adaptor. Therefore, the effect on different components of the CUL3 and NFE2L2 (NRF2) pathway was assessed in affected individuals' lymphocytes, revealing decreased mRNA expression of NFE2L2 and several NFE2L2 target genes. In conclusion, our study puts forward mutations in RCBTB1 as a cause of autosomal-recessive non-syndromic and syndromic iRD. Finally, our data support a role for impaired ubiquitination in the pathogenetic mechanism of RCBTB1 mutations.

Intravitreal ketorolac for the treatment of chronic cystoid macular edema after cataract surgery.

PURPOSE: To report two cases of chronic postoperative cystoid macular edema, resistant to topical therapy, treated with consecutive intravitreal injections of ketorolac tromethamine. METHODS: Four daily intravitreal injections of 500 µg/0.05 mL of ketorolac were given to each patient. Complete clinical examination and OCT were performed before every injection, 1, 2, 3 weeks, and 1, 3, and 6 months after the last injection. Fluorescein angiography was performed at baseline examination, 1, 3, and 6 months after the last injection. RESULTS: In both cases, the edema regressed and visual acuity increased. At 6 months after the last injection, the leakage was significantly reduced at the fluorescein angiography. DISCUSSION: Both cases responded favorably to the consecutive intravitreal administration of ketorolac tromethamine. The long-lasting remission of the macular edema in these chronic cases underlines the therapeutic potential of these agents when delivered intravitreally.

Differential monocular vs. binocular pupil responses from melanopsin-based photoreception in patients with anterior ischemic optic neuropathy.

We examined the effect of anterior ischemic optic neuropathy (AION) on the activity of intrinsically photosensitive retinal ganglion cells (ipRGCs) using the pupil as proxy. Eighteen patients with AION (10 unilateral, 8 bilateral) and 29 age-matched control subjects underwent chromatic pupillometry. Red and blue light stimuli increasing in 0.5 log steps were presented to each eye independently under conditions of dark and light adaptation. The recorded pupil contraction was plotted against stimulus intensity to generate scotopic and photopic response curves for assessment of synaptically-mediated ipRGC activity. Bright blue light stimuli presented monocularly and binocularly were used for melanopsin activation. The post-stimulus pupil size (PSPS) at the 6th second following stimulus offset was the marker of intrinsic ipRGC activity. Finally, questionnaires were administered to assess the influence of ipRGCs on sleep. The pupil response and PSPS to all monocularly-presented light stimuli were impaired in AION eyes, indicating ipRGC dysfunction. To binocular light stimulation, the PSPS of AION patients was similar to that of controls. There was no difference in the sleep habits of the two groups. Thus after ischemic injury to one or both optic nerves, the summated intrinsic ipRGC activity is preserved when both eyes receive adequate light exposure.

Clinical and spectral-domain optical coherence tomography findings of patients with incomplete visual recovery after anatomically successful retinal detachment surgery.

Purpose. To identify causes of incomplete visual recovery in patients with anatomically successful retinal detachment surgery. Methods. This was a retrospective study of 61 eyes of 61 patients with at least 12-month follow-up and complete preoperative, intraoperative, and postoperative record. Postoperative visual acuity (VA) more than 0.18 logMAR was considered as incomplete visual recovery. Complete ophthalmic examination and Spectral-Domain OCT (SD-OCT) imaging were performed at last follow-up. Results. Twenty-nine eyes (47.5%) had a postoperative VA < 0.18 logMAR and 32 eyes (52.5%) had a postoperative VA ≥ 0.18 logMAR. Mean follow-up was 32.8 ± 17.3 months. Incomplete visual recovery was strongly correlated with presence of macular pathology (P = 0.002), a detached macula preoperatively (P = 0.02), retinotomy (P = 0.025), and pars plana vitrectomy and use of silicon oil as a tamponade agent (P = 0.009). Also, although there was a strong correlation between ellipsoid zone disruption and incomplete visual recovery, a distinct, more course pathology could be identified in all cases of poor visual recovery related to edema, thickening, or atrophy of the macula. Conclusion. The careful postoperative evaluation of the macula using biomicroscopy and SD-OCT can help in diagnosis of alterations that can be associated with incomplete visual recovery.

The effect of intravitreal anti-VEGF on the pigment epithelial detachment in eyes with the exudative type of age-related macular degeneration.

PURPOSE: To evaluate the effect of anti-VEGF treatment on pigment epithelial detachment (PED) secondary to the exudative type of age-related macular degeneration (AMD). METHODS: Retrospective analysis of 30 eyes (28 patients) with exudative AMD accompanied by PED (receiving anti-VEGF injections). Alterations of the PED morphology were qualitatively assessed with optical coherence tomography (OCT). Changes in best-corrected visual acuity (BCVA) and number of injections were compared to 30 control eyes (30 patients) exhibiting exudative AMD without PED. RESULTS: Mean follow-up was 19.8 months. Changes of the extent of PED were as follows: unchanged: 11 eyes (36.7%); reduced: 12 (40%); significantly reduced: 7 (23.3%). Mean paired difference in BCVA was -0.08 logMAR (p = 0.46) and in the number of injections was 2.1 injections (p = 0.04). CONCLUSIONS: A substantial number of the studied patients showed reduction of the extent of the PED after anti-VEGF treatment. The PED group required a higher number of injections.

Surgical and visual outcome for recurrent retinal detachment surgery.

Purpose. To evaluate the anatomical and functional outcome of repeated surgeries for recurrent retinal detachment. Methods. We retrospectively reviewed 70 cases with refractory retinal detachment of various etiologies that required multiple operations. Anatomical success (attached retina) or failure (totally/partially-detached retina) was assessed biomicroscopically. The BCVA was used for the evaluation of the functional outcome, at presentation and at the end of follow-up. Various pre-, intra-, and postoperative factors were associated with anatomical success or failure as well as with final functionality. Results. The mean number of surgeries was 4 (range: 2 to 10). The anatomical success rate was 80% (56 attached cases, 14 detached cases). 29% of the attached cases had a BCVA better than 20/40 (Snellen chart). The number of operations doesn't seem to affect significantly the final visual acuity. The PVR was found to affect both the anatomical and functional outcome (P = 0.014 & P = 0.002, respectively). Conclusions. In the present study, it is suggested that multiple operations for refractory retinal detachment may result in successful anatomic results, with a fare functional outcome at the same time. Eventually, we verified that the existence of PVR worsens the prognosis.

Evaluation of vitreous clearance and potential retinal toxicity of intravitreal lornoxicam (xefo).

PURPOSE: To evaluate the vitreous clearance and toxicological profile of commercially available lornoxicam (Xefo), after a single intravitreal injection in rabbits. METHODS: Twenty-five male albino rabbits (10 rabbits were used for retinal toxicity evaluation, while 15 rabbits were used to evaluate vitreous clearance) were used in this study. Two concentrations of lornoxicam were tested for retinal toxicity: 250 µg/0.1 mL and 1,500 µg/0.1 mL. Each concentration was intravitreally injected randomly in 1 eye of each rabbit (group I received 250 µg/0.1 mL, n=5 and group II received 1,500 µg/0.1 mL, n=5), while in the other eye 0.1 mL of sterile balanced saline solution was injected. Slit-lamp and funduscopic examinations along with intraocular pressure measurements (IOP) were performed prior to injection and at days 1, 15, and 30 after the injection for signs of infection, inflammation, toxicity, and IOP changes. A baseline electroretinogram (ERG) was performed before the experiment and at days 1, 15, and 30 after the intravitreal injection. At the last follow-up day, the animals were sacrificed and the enucleated eyes were prepared for histological evaluation of the retina. Lornoxicam (concentration of intravitreal injection: 250 µg/0.1 mL) clearance from the vitreous was estimated using high-performance liquid chromatography in 30 rabbit eyes. RESULTS: There were no statistical differences between the control and experimental eyes, concerning ERG amplitudes and IOP measurements for both groups (I and II), at all examinations. On the contrary, histological examination of the samples revealed extended retinal damage of group II experimental eyes (morphological alterations at the level of the inner nuclear and outer plexiform layers was evident along with disappearance of normal stratification of outer retina with vacuolization and thinning), whereas the morphology of group I experimental eyes did not differ from that of the control eyes. Lornoxicam is eliminated from the vitreous by a first-order kinetic process with a half-life of 1.7 h. CONCLUSIONS: Intravitreal lornoxicam causes dose-related toxic effect to the retina at a concentration of 1,500 µg. A dose of 250 µg does not seem to cause histological toxic effects at the level of the retina. Lornoxicam could be considered with interest for further research for the development of alternative treatments for ocular inflammatory conditions.

Effect of panretinal photocoagulation treatment on vision-related quality of life of patients with proliferative diabetic retinopathy.

PURPOSE: To evaluate the effect of laser panretinal photocoagulation for bilateral proliferative diabetic retinopathy on vision-related quality of life. METHODS: In this prospective study, 20 patients (12 men and 8 women) with bilateral proliferative diabetic retinopathy treated with panretinal photocoagulation were included (mean age: 65 years, SD: 11.6 years). On average, patients received 2,140 laser spots per eye. The National Eye Institute 25-Item Visual Function Questionnaire (VFQ-25) was used to evaluate patients' vision-related quality of life. The VFQ-25 was filled in by interview twice, at the beginning and at least 1 month after the completion of panretinal photocoagulation. Comparison of preoperative and postoperative VFQ-25 composite and subscale scores was performed. Correlation was evaluated between change in composite score and treatment intensity as indicated by mean number in laser spots. RESULTS: Mean composite score before laser treatment was 71.9 ± 14.8 and after treatment it was 70.6 ± 17.2 (P = 0.748, paired t-test). None of the subscale scores had a statistically significant difference before and after treatment. Composite score change was not correlated with treatment intensity. CONCLUSION: Panretinal photocoagulation as applied in our study, although destructive in nature, is well tolerated by the patients, without interfering significantly with their quality of life.

Assessment of macular pigment optical density (MPOD) in patients with unilateral wet age-related macular degeneration (AMD).

PURPOSE: To compare the macular pigment optical density (MPOD) of patients with unilateral wet age-related macular degeneration (AMD) with the MPOD of bilateral dry AMD patients and healthy elderly individuals. METHODS: The MPOD of 34 patients with unilateral wet AMD was measured in their fellow eye that had the dry form of the disease (study group). The MPOD of the study group was compared with the MPOD of 33 patients with bilateral dry AMD (patients' control group) and 35 elderly subjects without any signs of retinal disease (control group). None of the subjects was under carotenoid supplementation. The MPOD was measured with Heterochromatic Flicker Photometry [QuantifEYE™- MPS 9000 (ZeaVision(©))]. The statistical package SPSS v 17.0 was used for the analysis. RESULTS: The overall mean MPOD was 0.52 (SD 0.15). Patients with unilateral wet AMD have significantly higher levels of MPOD in their fellow eye compared with patients with bilateral dry AMD (0.58 versus 0.48, p = 0.026). Mean MPOD of patients with bilateral dry AMD does not differ significantly from that of healthy elderly subjects (0.48 versus 0.50, p = 0.865). In this population sample, no correlation with age was observed, while women have slightly but significantly higher levels of MPOD (0.55 versus 0.49, p = 0.029). CONCLUSION: In the present study, the mean MPOD at the fellow eye of patients with unilateral wet AMD was found to be significantly higher than that of patients with bilateral dry AMD, while no other significant difference emerged between groups. Further investigation is demanded to clarify the role of macular pigment in AMD progression.

Intravitreal combination of triamcinolone acetonide and bevacizumab (Kenacort-Avastin) in diffuse diabetic macular edema.

PURPOSE: To evaluate the effect of intravitreal injection of the combination of Triamcinolone Acetonide and Bevacizumab in patients with diabetic macular edema. MATERIALS AND METHODS: Twenty seven eyes of 17 patients with diabetic macular edema were treated with an intravitreal injection of triamcinolone acetonide (2 mg) combined with bevacizumab (1.25 mg). RESULTS: During the 6 months follow-up period 24 eyes (89%) had to repeat the treatment according to the monthly follow-up examination.The mean visual acuity and the central macular thickness improved significantly (P<0.05) throughout the follow-up period. CONCLUSION: Intravitreal combination of Triamcinolone Acetonide and Bevacizumab seems to be effective in improving visual acuity and macular edema in patients with diabetic maculopathy.