El espacio supracoroideo en pacientes afectados por retinosis pigmentaria / The suprachoroidal space in patients affected by retinitis pigmentosa

Antecedentes y objetivo: El espacio supracoroideo (SCS) es una estructura teórica que se sitúa entre el borde interno de la esclera y el límite externo del coroides. El SCS está siendo estudiado por sus posibles usos como vía para la administración de medicamentos y por técnicas quirúrgicas innovadoras para el tratamiento de muchas enfermedades retinianas. La retinitis pigmentosa (RP) es un grupo de trastornos hereditarios y progresivos caracterizados por el detrimento gradual de fotorreceptores que conduce a una discapacidad visual que se manifiesta típicamente como hemeralopía y pérdida progresiva del campo visual. El objetivo del estudio fue definir la morfología de los márgenes coroideos externos mediante el uso de tomografía de coherencia óptica de barrido (SS-OCT) en la RP.Materiales y métodosEstudio observacional retrospectivo diseñado para evaluar la presencia del ESC en la RP. Realizamos SS-OCT en un grupo de 55 pacientes afectados por RP (26 hombres y 29 mujeres, 110 ojos) con una edad media de 51,8±13,7 años. En el grupo de control incluimos a 28 sujetos sanos (6 hombres y 22 mujeres, 56 ojos) con una edad media de 48,8±16,6 años.ResultadosLas imágenes OCT permitieron delinear de manera precisa el margen coroideo externo y el margen escleral interno en los 110 ojos. En el grupo RP se detectó el ESC en 47 de los 110 ojos (42,7%), en el grupo de control se detectó el ESC en 11 ojos (19,6%).Los sujetos del grupo RP con SCS visibles presentaron un menor grosor retiniano (168,4 micrones) en comparación con aquellos con SCS visibles (211,2 micrones, p=0,007). (AU)

Background and objective: The suprachoroidal space (SCS) is a theoretical structure which can be demonstrated between the inner border of the sclera and the outer boundary of the choroid. SCS is being studied for its potential uses as a route for drug delivery and innovative surgical techniques for the treatment of many retinal diseases. Retinitis pigmentosa (RP) is a group of inherited eye disorders characterized by a gradual loss of photoreceptors, resulting in vision impairment, which typically presents as night blindness and progressive visual field loss. The purpose of the study is to define the morphology of outer choroidal margins by means of SS-OCT in RP.Material and methodThis is a retrospective observational study designed to evaluate the presence of SCS in RP. We performed swept source optical coherence tomography (SS-OCT) in a group of 55 patients affected by RP (26 males and 29 females, 110 eyes) with a mean age of 51.8±13.7 years. In the control group, we included 28 healthy subjects (6 males and 22 females, 56 eyes) with a mean age of 48.8±16.6 years.ResultsOCT scans allowed the outer choroidal margin and inner scleral margin to be delineated with certainty in all 110 eyes. In the RP group SCS was detected in 47 of 110 eyes (42.7%), in the control group SCS was detected in 11 eyes (19.6%).Subjects with SCS visible (RP group) had reduced retinal thickness (168.4μm) compared to those with not visible SCS (211.2μm, p=0.007). (AU)

The suprachoroidal space in patients affected by retinitis pigmentosa.

BACKGROUND AND OBJECTIVE: The Suprachoroidal Space (SCS) is a theoretical structure which can be demonstrated between the inner border of the sclera and the outer boundary of the choroid. SCS is being studied for its potential uses as a route for drug delivery and innovative surgical techniques for the treatment of many retinal diseases. Retinitis pigmentosa (RP) is a group of inherited eye disorders characterized by a gradual loss of photoreceptors, resulting in vision impairment, which typically presents as night blindness and progressive visual field loss. The purpose of the study is to define the morphology of outer choroidal margins by means of SS-OCT in RP. MATERIAL AND METHOD: This is a retrospective observational study designed to evaluate the presence of SCS in RP. We performed Swept Source optical coherence tomography (SS-OCT) in a group of 55 patients affected by RP (26 males and 29 females, 110 eyes) with a mean age of 51.8 ±â€¯13.7 years. In the control group, we included 28 healthy subjects (6 males and 22 females, 56 eyes) with a mean age of 48,8 ±â€¯16,6 years. RESULTS: OCT scans allowed the outer choroidal margin and inner scleral margin to be delineated with certainty in all 110 eyes. In the RP group SCS was detected in 47 of 110 eyes (42,7%), in the control group SCS was detected in 11 eyes (19,6%). Subjects with SCS visible (RP group) had reduced retinal thickness (168.4 µm) compared to those with not visible SCL (211.2 µm, P = .007). CONCLUSIONS: SS-OCT can be successfully applied to assess the presence of SCS in RP and the high rate of SCS found in the RP patients is encouraging when considering future innovative therapies.

X-linked retinoschisis: mutation spectrum and genotype-phenotype relationship in an Italian pediatric cohort.

BACKGROUND: X-linked juvenile retinoschisis (×LRS) is an X-linked vitreoretinal degenerative disease that consists of variable phenotypes ranging from severe early-onset defects to subtle abnormalities diagnosed in elderly patients. XLRS is caused by a loss of function of the protein Retinoschisin (RS1), which is essential to preserve retinal integrity and function of photoreceptor-bipolar synapse. The literature data so far mostly agree on the absence of a clear genotype-phenotype correlation in XLRS. We reviewed clinical and molecular characteristics of a cohort of Italian pediatric XLRS patients to assess the presence of a correlation between genotype and phenotype severity. MATERIALS AND METHODS: We retrospectively examined clinical and genetic features of a cohort of 27 XLRS patients. In this study we included patients with a diagnosis of XLRS confirmed by fundus photography, spectral domain optical coherence tomography, and molecular analysis and with an onset of less than 10 years of age. We sorted RS1 variants according to their effect of RS1 structure and function in three separate groups. RESULTS: According to previous studies, we did not observe a conclusive genotype-phenotype correlation in our cohort; nevertheless, we noticed that patients harboring RS1 variants leading to RS1-secreted mutants show a more homogeneous phenotype, with an overall good visual acuity, compared to the other two groups. CONCLUSIONS: Our data support the hypothesis that secretion profile of RS1 could influence the severity of the phenotype. More extensive and functional studies are needed to acquire notions in view of the opportunity of gene replacement therapy for XLRS patients.

Treatment patterns of ranibizumab intravitreal injection and dexamethasone intravitreal implant for retinal vein occlusion in the USA.

PurposeRanibizumab, an anti-vascular endothelial growth factor, and dexamethasone, a corticosteroid, have been shown to be effective in treating macular oedema secondary to retinal vein occlusion (RVO) (central RVO (CRVO) and branch RVO (BRVO)). Their real-world usage, however, has yet to be compared. We therefore evaluated ophthalmology visits for both drugs using US patient-level data.MethodsThe IMS Health Real-World Data Medical Claims database was used to identify treatment-naive patients receiving ranibizumab intravitreal injections or dexamethasone intravitreal implants between June 2010 and February 2014 who had 12 months of follow-up data. The primary outcome measure was the mean number of all ophthalmology visits for the two drugs in patients with CRVO and BRVO. Secondary outcome measures included a comparison of treatment visits, non-treatment visits, and time intervals between visits.ResultsOverall, 2822 patients received ranibizumab injections (CRVO, 1178; BRVO, 1644) and 365 received dexamethasone implants (CRVO, 191; BRVO, 174). The mean number (SD) of all ophthalmology visits was higher for patients receiving ranibizumab injections than for those receiving dexamethasone implants (CRVO: 7.2 (3.6) vs 6.2 (3.1), P<0.001; BRVO: 7.1 (3.4) vs 6.3 (3.1), P=0.016).ConclusionsPatients with RVO receiving ranibizumab injections had a mean of approximately one more visit to their ophthalmologist in the first 12 months of treatment than those treated with dexamethasone implants. The visit burden is therefore not substantially different and physicians should focus on the clinical benefits of these drugs when evaluating treatment options for RVO.

Erythrocyte oxidative stress is associated with cell deformability in patients with retinal vein occlusion.

Essentials Retinal vein occlusion (RVO), characterized by blood hyperviscosity, has an unclear pathogenesis. We aimed to find out if hemorheological profile is altered by oxidative stress in RVO patients. Red blood cell (RBC) oxidative stress is associated to whole blood viscosity and RBC deformability. Reactive oxygen species alter RBC membrane rigidity, playing a key role in RVO pathogenesis. SUMMARY: Background Retinal vein occlusion (RVO) is characterized by vision loss resulting from hypoperfusion and hypoxia of the retina. RVO pathogenesis is not yet fully understood, although blood hyperviscosity has been observed. Erythrocyte deformability plays a key role in determining blood viscosity, and it is critical to microvascular perfusion and oxygen delivery. It has been shown that oxidative stress-induced erythrocyte membrane fluidity alterations are linked to the progression of cardiovascular diseases. Objectives To determine whether erythrocytes from RVO patients show signs of oxidative stress, and whether this condition can modify the hemorheologic profile in these patients. Patients and Methods We analyzed the entire hemorheologic profile and erythrocyte oxidative stress - reactive oxygen species (ROS) production and membrane lipid peroxidation - in 128 RVO patients and 128 healthy subjects, matched for age and sex. Fluorescence anisotropy was used to evaluate the fluidity of erythrocyte membranes. Results In RVO patients, erythrocyte oxidative stress was present and positively correlated with whole blood viscosity and erythrocyte deformability. Multivariate linear regression analysis after adjustment for age, cardiovascular risk factors, medications, leukocyte number and mean corpuscular volume indicated that erythrocyte-derived ROS and erythrocyte lipid peroxidation were significantly and positively correlated with erythrocyte membrane viscosity and deformability. Moreover, in vitro experiments demonstrated that ROS have a key role in erythrocyte membrane fluidity. Conclusions Our findings indicate that erythrocyte oxidative stress plays a key role in the pathogenesis of RVO, and pave the way to new therapeutic interventions.

Aroma characterisation and UV elicitation of purple basil from different plant tissue cultures.

Exposure to stressful environmental conditions can induce severe metabolic variations in basil (Ocimum basilicum) aroma. The aromatic profiles of Dark Opal and Red Rubim varieties (in vivo plants, in vitro shoots, callus, and suspension cultures) were investigated for the first time. The established calli represented the most interesting miniaturised aromatic plant systems, as they were able to emit many typical basil volatiles with very low amounts of phenylpropanoids (1-2%). The hydrocarbon monoterpenes and oxygenated volatiles emitted from calli of both varieties were greatly and conversely affected by UV-C and UV-B, in comparison with the non-irradiated samples. As calli of both varieties still maintained very low levels of phenylpropanoids even after UV elicitation, they might be regarded not only as efficient in vitro plant models to study volatile compounds under UV stress conditions, but also as safe aromatic biomass in comparison with in vivo basil plants.

Distinct mechanisms for aerenchyma formation in leaf sheaths of rice genotypes displaying a quiescence or escape strategy for flooding tolerance.

BACKGROUND AND AIMS: Rice is one of the few crops able to withstand periods of partial or even complete submergence. One of the adaptive traits of rice is the constitutive presence and further development of aerenchyma which enables oxygen to be transported to submerged organs. The development of lysigenous aerenchyma is promoted by ethylene accumulating within the submerged plant tissues, although other signalling mechanisms may also co-exist. In this study, aerenchyma development was analysed in two rice (Oryza sativa) varieties, 'FR13A' and 'Arborio Precoce', which show opposite traits in flooding response in terms of internode elongation and survival. METHODS: The growth and survival of rice varieties under submergence was investigated in the leaf sheath of 'FR13A' and 'Arborio Precoce'. The possible involvement of ethylene and reactive oxygen species (ROS) was evaluated in relation to aerenchyma formation. Cell viability and DNA fragmentation were determined by FDA/FM4-64 staining and TUNEL assay, respectively. Ethylene production was monitored by gas chromatography and by analysing ACO gene expression. ROS production was measured by using Amplex Red assay kit and the fluorescent dye DCFH(2)-DA. The expression of APX1 was also evaluated. AVG and DPI solutions were used to test the effect of inhibiting ethylene biosynthesis and ROS production, respectively. KEY RESULTS: Both the varieties displayed constitutive lysigenous aerenchyma formation, which was further enhanced when submerged. 'Arborio Precoce', which is characterized by fast elongation when submerged, showed active ethylene biosynthetic machinery associated with increased aerenchymatous areas. 'FR13A', which harbours the Sub1A gene that limits growth during oxygen deprivation, did not show any increase in ethylene production after submersion but still displayed increased aerenchyma. Hydrogen peroxide levels increased in 'FR13A' but not in 'Arborio Precoce'. CONCLUSIONS: While ethylene controls aerenchyma formation in the fast-elongating 'Arborio Precoce' variety, in 'FR13A' ROS accumulation plays an important role.

Novel mutations in of the ABCR gene in Italian patients with Stargardt disease.

PURPOSE: Stargardt disease (STGD) is the most prevalent juvenile macular dystrophy, and it has been associated with mutations in the ABCR gene, encoding a photoreceptor-specific transport protein. In this study, we determined the mutation spectrum in the ABCR gene in a group of Italian STGD patients. METHODS: The DNA samples of 71 Italian patients (from 62 independent pedigrees), affected with autosomal recessive STGD, were analysed for mutations in all 50 exons of the ABCR gene by the DHPLC approach (with optimization of the DHPLC conditions for mutation analysis) and direct sequencing techniques. RESULTS: In our group of STGD patients, 71 mutations were identified in 68 patients with a detection rate of 95.7%. Forty-three mutations had been already reported in the literature, whereas 28 mutations had not been previously described and were not detected in 150 unaffected control individuals of Italian origin. Missense mutations represented the most frequent finding (59.2%); G1961E was the most common mutation and it was associated with phenotypes in various degrees of severity. CONCLUSIONS: Some novel mutations in the ABCR gene were reported in a group of Italian STGD patients confirming the extensive allelic heterogeneity of this gene-probably related to the vast number of exons that favours rearrangements in the DNA sequence.

A normal electro-oculography in a family affected by best disease with a novel spontaneous mutation of the BEST1 gene.

AIMS: To describe clinical and genetic findings in an Italian family affected by Best disease. METHODS: Five related patients underwent a complete ophthalmological assessment; genetic testing was performed by single-strand conformation polymorphism analysis and direct sequencing of the BEST1 gene. RESULTS: In three of five family members, the sequence analysis of the BEST1 gene revealed a single Phe-to-Leu transition at nucleotide 305 associated with clinical evidence of Best disease. Surprisingly, the electro-oculogram was normal in all affected patients. CONCLUSION: This study reveals a de novo mutation in the BEST1 gene never described before, sustaining the autosomal-dominant pattern of inheritance of the disease. Clinical evaluation showed phenotypic variability between affected members. In addition, these data suggest that a normal electro-oculography (EOG) does not rule out a diagnosis of Best disease, supporting instead the crucial role of molecular analysis.

Atherosclerotic and thrombophilic risk factors in patients with recurrent central retinal vein occlusion.

PURPOSE: Atherosclerotic and thrombophilic risk factors may be causes of central retinal vein occlusion (CRVO). The aim of this study was to evaluate the prevalence of the aforesaid risk factors in patients with recurrent CRVOs and patients with a single episode of CRVO. METHODS: Seventeen patients with recurrent CRVO and 30 with a single episode of CRVO were enrolled. The atherosclerotic risk factors investigated were hypertension, diabetes, smoking, and dyslipidemia. Specific laboratory tests for the following thrombophilic markers were performed: homocystinemia (Hcy), lipoprotein (a), factor VIII, factor II G20210A and factor V G1691A polymorphisms, lupus anticoagulant, anticardiolipin antibodies, plasminogen activator inhibitor-1, and deficit of vitamins B6, B12, and folic acid. A multivariate analysis, adjusted for age, gender, traditional and thrombophilic risk factors, was performed. Statistical significance was set at p

Phenotypic intrafamilial variability associated with S212G mutation in the RDS/peripherin gene.

PURPOSE: To describe an Italian family in which two separate phenotypes (retinitis pigmentosa and adult onset vitelliform macular dystrophy) are associated with an identical mutation (S212G) in the peripherin/RDS gene. This mutation has already been reported in patients with retinitis pigmentosa, but it has never been previously detected in association with adult onset vitelliform macular dystrophy. METHODS: A 38-year-old woman complained of bilateral mild metamorphopsias and on ophthalmologic examination she showed the clinical phenotype of adult onset vitelliform macular dystrophy. Her 62-year-old mother was clinically diagnosed with a retinitis pigmentosa, with a severe clinical course. RESULTS: In both patients, molecular genetic analysis revealed a 874A-->G transition in the exon 2 of the RDS gene leading to the amino acid change of S212G. CONCLUSIONS: Peripherin/RDS S212G mutation may have damaging effects on the formation and stability of the photoreceptors' disk structure and may be associated with different clinical phenotypes, even in the same family. Intrafamilial phenotypic variability has been reported for other RDS mutations; this supports the possible influence of modifier genes or environmental factors in the clinical expression of RDS gene variants. Moreover, it suggests that in patients with retinal degeneration and peripherin/RDS mutation, caution should be taken both in using molecular genetic results to predict the clinical course of the disease and in offering genetic counseling.

Ocular surface temperature in central retinal vein occlusion: preliminary data.

PURPOSE: To compare ocular surface temperature (OST) measures in patients with central retinal vein occlusion (CRVO) and controls. METHODS: Thirty-six patients with unilateral CRVO and 54 healthy volunteers were included in the study. OST was evaluated by infrared thermography. RESULTS: In CRVO eyes and in fellow, nonaffected eyes, OST values were lower than in controls (p<0.05). Ischemic CRVO eyes showed lower temperatures than nonischemic ones. CONCLUSIONS: Infrared thermography may be helpful in the management of patients with CRVO.

A novel mutation in the VMD2 gene in an Italian family with Best maculopathy.

Vitelliform macular dystrophy (Best disease) is an inherited macular degeneration in which the primary defect is thought to occur at the level of the retinal pigment epithelium. The VMD2 gene, considered responsible for the disease, mapped to the long arm of chromosome 11, and it codifies the bestrophin protein, probably acting as a transmembrane ionic channel. In the present study, we screened for mutations the VMD2 gene in Italian patients with Best maculopathy. Five families with Best disease were recruited from central and southern Italy, and family members were evaluated by complete ophthalmologic examination and DNA analysis by means of DHPLC technology. Some mutations of the VMD2 gene were identified and among them there was a novel mutation (R218G), probably involving a functionally active region of the bestrophin protein. In spite of the small number of families considered, it was possible to note a significant phenotypic heterogeneity. First, in one family the R218C mutation was associated with early onset of choroidal neovascularization (CNV) in the affected mother and her son, while no CNV was reported in another family sharing the same mutation. Then a patient with the R25W mutation showed a multifocal location of the vitelliform deposits, while another family with the same mutation showed a typical isolated vitelliform disc in the macular area.

Occurrence of full-thickness macular hole complicating Stargardt disease with ABCR mutation.

PURPOSE: To report an unusual episode of full-thickness macular hole complicating Stargardt disease with an ABCR mutation. METHODS: Case report . RESULTS: Fundus examination of a 20-year-old healthy man showed typical fundus manifestation with yellowish-round or fish-like flecks associated with vitreous macular adhesion and a round punched-out area in the right eye. Optical coherence tomography (OCT) illustrated a full-thickness macular hole. Molecular genetic examination of the ABCR gene showed two heterozygous missense mutations: R1108C (CGC-->TGC) in exon 22 and a splicing mutation IVS6--> 1GT - described in the literature in association with Stargardt disease. CONCLUSIONS: Macular hole was once described in other inherited retinal degenerations (Best disease and Bietti crystal line retinopathy). The pathogenesis gives rise to a host of speculations: widespread alteration of the retinal pigment epithelium; inflammatory mechanisms; a minor trauma which might cause subretinal fibrosis. Surgical procedures were not performed on our patient after his ophthalmologic history and findings were considered.

Nitric oxide proxies and ocular perfusion pressure in primary open angle glaucoma.

BACKGROUND: To investigate the levels of nitric oxide (NO) markers in plasma and aqueous humour of patients with primary open angle glaucoma (POAG) and their relation to ocular perfusion pressure. METHODS: Cyclic guanosine monophosphate (cGMP) and nitrite (NO(2)(-)) were determined in plasma and aqueous humour of 38 patients with POAG and 46 controls. Blood pressure and IOP were measured to calculate ocular perfusion pressure (PP). RESULTS: cGMP and NO(2)(-) plasma levels were significantly decreased in glaucoma patients compared with controls (p = 0.001 v p = 0.004). In the aqueous humour of subjects with POAG, cGMP and NO(2)(-) concentrations were also lower than in normal eyes (p = 0.0001 v p = 0.001). There was a linear association between cGMP in plasma and aqueous humour in glaucomas and controls (r = 0.514, p = 0.029 and r = 0.558, p = 0.004) and this relation differed in the two groups (p = 0.003). Considering glaucoma patients with controls, a positive correlation was found between cGMP and PP (r = 0.379, p = 0.01) and between NO(2)(-) and PP (r = 0.339, p = 0.040). The cGMP/PP correlation was of borderline statistical significance in controls (p = 0.050), whereas it did not attain statistical significance in POAG, as well as the association between NO(2)(-) and PP when glaucomas and controls were considered separately. CONCLUSIONS: The authors found alterations of NO markers in the plasma and aqueous humour of glaucoma patients. Primary or secondary impaired NO balance could alter ocular perfusion pressure.

Early production and scavenging of hydrogen peroxide in the apoplast of sunflower plants exposed to ozone.

The present work set out to define the processes involved in the early O3-induced H2O2 accumulation in sunflower plants exposed to a single pulse of 150 ppb of O3 for 4 h. Hydrogen peroxide accumulation only occurred in the apoplast and this temporally coincided with the fumigation period. The inhibitor experiments suggested that both the plasma membrane-bound NAD(P)H oxidase complex and cell-wall NAD(P)H PODs contributed to H2O2 generation. To investigate the mechanisms responsible for O3-induced H2O2 accumulation further, both production and scavenging of H2O2 were investigated in the extracellular matrix after subcellular fractionation. The results indicated that H2O2 accumulation is a complex and highly regulated event requiring the time-dependent stimulation and down-regulation of differently located enzymes, some of which are involved in H2O2 generation and degradation, not only during the fumigation period but also in the subsequent recovery period in non-polluted air. Owing to the possible interplay between H2O2 and ethylene, the time-course of ethylene emission was analysed too. Ethylene was rapidly emitted following O3 exposure, but it declined to control values as early as after 4 h of exposure. The early contemporaneous detection of increased ethylene and H2O2 levels after 30 min of exposure does not allow a clear temporal relationship between these two signalling molecules to be established.