Complement Component C3 Variant (R102G) and the Risk of Neovascular Age-Related Macular Degeneration in a Tunisian Population.

Purpose To explore the association between the polymorphism (S/F) p.R102G in the complement component 3 (C3) gene and age-related macular degeneration (AMD) in a Tunisian population. Methods The molecular study was performed by polymerase chain reaction using sequence-specific primers (PCR-SSP) in 207 control subjects free of any eye disease (fundus normal) and 145 patients with exudative AMD. The CH50 activity and quantification of C3 and C4 have been made by technical home method and nephelometry, respectively. Results The prevalence of C3 GG genotype polymorphism was significantly higher in AMD patients compared to controls (OR: 2.41, IC 95% [1.90-3.05], p = 0.0007). However, no correlation was found between this allelic variant and the type of neovascularization. Similarly, there is no association between this polymorphism and the presence of functional and/or quantitative hypocomplementemia. Conclusions The C3 GG genotype of the gene could be a susceptibility factor for AMD in the Tunisian population. However, it does not seem to influence the clinical profile of the disease.

Identifying mutations in Tunisian families with retinal dystrophy.

Retinal dystrophies (RD) are a rare genetic disorder with high genetic heterogeneity. This study aimed at identifying disease-causing variants in fifteen consanguineous Tunisian families. Full ophthalmic examination was performed. Index patients were subjected to IROme analysis or whole exome sequencing followed by homozygosity mapping. All detected variations were confirmed by direct Sanger sequencing. Mutation analysis in our patients revealed two compound heterozygous mutations p.(R91W);(V172D) in RPE65, and five novel homozygous mutations: p.R765C in CNGB1, p.H337R in PDE6B, splice site variant c.1129-2A > G and c.678_681delGAAG in FAM161A and c.1133 + 3_1133 + 6delAAGT in CERKL. The latter mutation impacts pre-mRNA splicing of CERKL. The other changes detected were six previously reported mutations in CNGB3 (p.R203*), ABCA4 (p.W782*), NR2E3 (p.R311Q), RPE65 (p.H182Y), PROM1 (c.1354dupT) and EYS (c.5928-2A > G). Segregation analysis in each family showed that all affected individuals were homozygotes and unaffected individuals were either heterozygote carriers or homozygous wild type allele. These results confirm the involvement of a large number of genes in RD in the Tunisian population.

Spectral Domain optical coherence tomography findings in patients with retinitis pigmentosa.

Background Maculopathy is a common complication of retinitis pigmentosa (RP), and compromise the visual acuity of RP patients even in the less advanced stages. Aim To report the morphological macular findings detected by spectral domain optical coherence tomography (SD-OCT) and to determine their prevalence in patients with retinitis pigmentosa (RP). Methods  SD-OCT scans from 100 patients (196 eyes) affected by RP were reviewed. Results We noted a normal macula appearance in 48.5%, macular edema in 14.5% and macular atrophy in 37%. Mean central macular thickness was 167.79 microns and we did not note any statistically significant correlation between visual acuity and foveal thickness. Visual acuity was statistically better in eyes with a larger number of hyper-reflective layers (p<0.001) and in eyes with photoreceptor inner/outer (IS/OS) segment junction distinct (p<0.001). We have identified three types of tomographic macular edema: a cystoids macular edema in 6.8%, a tractional edema in 8.2% and mixed edema in 1%. We identified two tomographic types of macular atrophy: a central- foveal atrophy in 34 eyes (11.6%) and diffuse atrophy in 38 eyes (12.9%). Epiretinal membrane was present in 24 eyes (8.2%). Conclusions The OCT contributes to the analysis of epidemiological and morphological of different macular involvement in RP. OCT has a prognostic value, which essentially depends on the morphology of the IS/OS line and number of hyper-reflective layers.

Epidemiologic study of myopia in a population of schoolchildren in Tunisia.

BACKGROUND: Uncorrected refractive error has recently been identified as the leading cause of visual impairment in children worldwide. The prevalence of myopia is increasing. Determination of the epidemiology of myopia is important to develop screening strategy. PURPOSE: to estimate the prevalence and the degree of severity of myopia among primary schoolchildren in Tunisia and to assess its effect on school performance. METHODS: A random cluster design was used to recruit children from primary schools across urban and rural settings in Tunisia, during 2009 to 2012. A total of 6192 students aged 6 to 14 years old were enrolled. Students with visual acuity of 9/10 or worse underwent a complete ophthalmic examination, and cycloplegic autorefraction was used to determine refractive error. Myopia was defined as a spherical equivalent (SE) of - 0.50 dioptre (D) or worse. We also searched for a possible relation between uncorrected myopia and academic failure. RESULTS: The prevalence of myopia was 3.71%. Mean and SD of spherical equivalent was -3,10 ± 0,86 D. The myopia rate increased significantly with age (p=0.04), but was not significantly related to gender (p=0.823). There was no significant association between the student's area of residence and myopia (p=0.932). 85.21% of myopic students experienced unsatisfactory academic performances. CONCLUSION: The present study reveals the prevalence of myopia among schoolchildren in Tunisia. The high rate of academic failure in myopic schoolchildren emphasizes an unmet need for its screening and its correction.

Characteristics of Astigmatism in a Population of Tunisian School-Children.

PURPOSE: To evaluate the characteristics of astigmatism in a cross-sectional study of schoolchildren in Tunisia. MATERIALS AND METHODS: A random cluster design was used to recruit children from primary schools across urban and rural settings in Tunisia, from 2008 to 2010. A total of 6192 students aged 6-14-years old were enrolled. All students whose uncorrected visual acuity was worse than 20/20 underwent a complete ophthalmic examination. Astigmatism was defined as the cylinder power of 0.75 diopter (D) or greater. RESULTS: The prevalence of astigmatism was 6.67%. Mean cylinder power was - 1.89 ± 0.79D. The prevalence of astigmatism increased statistically significantly with age (P = 0.032). The prevalence of astigmatism was not significantly related to gender (P = 0.051). Of those with cylinder, 63.6%, 17.8%, and 18.6% schoolchildren had with with-the-rule, against-the-rule, and oblique astigmatism, respectively. ATR astigmatism was significantly higher in males (P = 0.033). There was no significant association between the student's area of residence and astigmatism (P = 0.059). CONCLUSION: Comparisons with other studies show that the prevalence of astigmatism in Tunisia is higher than in some countries. The prevalence of astigmatism increased with age but not gender. The majority of schoolchildren had with-the-rule astigmatism.

Current and emerging treatment options for myopic choroidal neovascularization.

Choroidal neovascularization (CNV) is the main cause of visual impairment in highly myopic patients younger than 50 years of age. There are different treatments for myopic CNV (mCNV), with 5- to 10-year outcomes currently. Chorioretinal atrophy is still the most important determinant factor for visual outcome. The purpose of this study is to provide an overview of the current treatments for mCNV, including laser, surgical management, verteporfin photodynamic therapy, and mainly anti-vascular endothelial growth factor therapy. Emerging treatment options are also discussed.

Vascular endothelial growth factor genetic polymorphisms and susceptibility to age-related macular degeneration in Tunisian population.

PURPOSE: Three VEGF SNPs (-2578) C/A, (+405) G/C and (+936) C/T were investigated in Tunisian exudative AMD patients in order to determine their association with the disease susceptibility and their influence to intravitreal bevacizumab therapy response. METHODS: 145 AMD patients and 207 age-matched controls were included. 68 patients were treated with intravitreal bevacizumab. SNPs genotyping were performed using direct sequencing. The serum VEGF was assayed by ELISA (R&D). RESULTS: The (+405) CC and (+936) TT genotypes were higher in AMD patients than in controls (p = 5 × 10(-6) and p = 0.021, respectively). The mean plasma levels of VEGF were statistically higher in AMD patients (84.22 pg/ml) than in controls (15 pg/ml). Three months after bevacizumab treatment, 52 patients (85.6%) were classified as good responders (GR) and 16 (14.4%) as poor responders (PR). The mean plasmatic-VEGF levels in GR patients was higher (86.61 ± 80.30 pg/ml) than in PR patients (47.12 ± 45.74 pg/ml) (p = 0.086). The patients with genotype homozygous TT (+936) would be PR compared to those carrying CT and CC genotypes. Whereas, those with AA (-2578) genotype would be GR compared with others genotypes (p = 0.014; p = 0.042 respectively). CONCLUSIONS: Our results show that VEGF genetic variants may contribute to the susceptibility to neovascular AMD in Tunisian patients.

[Epidemiologic study of hyperopia in schoolchildren in Tunisia]. / Profit épidémiologique de l'hypermétropie en milieu scolaire primaire en Tunise: à propos de 6192 enfants.

AIM: To study the epidemiological profile and the degree of severity of hyperopia in Tunisia primary school and to assess its effect on school performance. METHODS: A cross-sectional, descriptive survey was conducted among 6-14 aged Tunisian children attending primary urban and rural schools. A total of 6192 children were selected using stratified random cluster sampling. Cycloplegic refractive error was measured among all children with uncorrected visual acuity less than 9/10 or signs of astheniopia. Hyperopia was defined as spherical equivalent (SE) 2.0 diopters (D). We have also searched a possible relation between degree of severity of hyperopia and school performance. RESULTS: The prevalence of hyperopia was 2.61%. The spherical equivalent mean was + 3.73 ± 0.94 D. The mean age was 9.67 ± 0.44 years. This prevalence was 2.77% in boys and 2.47% in girls. 3.13% of students were living in urban areas and 1.42% in rural areas. The hyperopia rate decreased significantly with age (p = 0.021), but it was not significantly related to gender (p=0.54). The difference in the prevalence of hyperopia between urban and rural areas was not statistically significant (p = 0.067). There was no significant association between the degree of severity of hyperopia and school performance (p=0.41). CONCLUSION: In our study, the prevalence of hyperopia among schoolage children in Tunisia was 2.61%.The identification of this refractive error and its correction as soon as possible would ensure these children better visual comfort and a better education.

Choroidal thickness measurement in highly myopic eyes using SD-OCT.

BACKGROUND AND OBJECTIVE: To measure macular choroidal thickness (CT) using spectral-domain optical coherence tomography (OCT) and to investigate the correlation between CT and age, degree of myopia, and history of macular choroidal neovascularization (CNV). PATIENTS AND METHODS: A cross-sectional study included 187 highly myopic eyes of 187 patients examined between January and December 2010. The choroid was imaged with spectral-domain OCT by changing the reference position from the vitreous to the choroid. CT was measured from the outer border of the hyperreflective line corresponding to the retinal pigment epithelium to the inner scleral border. RESULTS: The mean age was 47.21 ± 14.24 years, the mean spherical equivalent refractive error was -13.66 ± 5.77, and the mean subfoveal CT was 100.71 ± 59.98 µm. CT was correlated negatively with age (P < 10(-3)) and refractive error (P < 10(-3)). Forty-two eyes had a history of CNV, the mean CT was 55.45 ± 24.46 µm, and this was significantly thinner than in eyes without CNV (P < 10(-3)). CONCLUSION: In highly myopic eyes, the choroid is thin and undergoes further attenuation with age and increasing myopia. In addition, these findings suggest that the choroid may play a role in the pathogenesis of CNV.

Bevacizumab injection in patients with age-related macular degeneration associated with poor initial visual acuity.

Purpose. To evaluate functional and anatomic effects of intravitreal bevacizumab in patients with neovascular AMD and initial low visual acuity. Methods. Retrospective case series of 38 eyes with neovascular AMD and initial visual acuity of 20/200 or less, treated with intravitreal bevacizumab injection. Results. Mean followup was 14.1 months ± 7.1 (range: 5 to 24 months). Mean logMAR vision at baseline was 1.38 logMAR ± 0.33, at 6 months was 1.14 logMAR ± 0.37 (P = 0.001) and at 12 months was 1.22 logMar ± 0.33 (P = 0.004). Mean baseline central retinal thickness was 431 µm ± 159.7 at 6 months was 293.43 µm ± 122.79 (P = 10(-4)) and at 12 months was 293.1 µm ± 130 (P = 0.004). Visual acuity improved in both patients with or without prior PDT treatment. Conclusions. Intravitreal bevacizumab injection may increase the chance of visual acuity gain in neovascular AMD even in cases with initial low visual acuity.

Intravitreal bevacizumab versus photodynamic therapy for myopic choroidal neovascularization in a North-African population.

PURPOSE: To compare the 1-year functional and anatomical outcomes of intravitreal bevacizumab (IVB) and photodynamic therapy (PDT) in patients with myopic choroidal neovascularization (CNV). METHODS: Review of retrospectively collected data of 80 eyes in 80 patients with myopic CNV treated with standard PDT (n = 40) or IVB (1.25 mg/ 0.05 ml) (n = 40). Best-corrected visual acuity (BCVA) and central retinal thickness (CRT) measured with optical coherence tomography (OCT) were compared between the two groups at baseline, 3, 6 and 12 months. RESULTS: In the IVB group, mean BCVA was +0.9 ± 0.85 logMAR at baseline. Mean BCVA was significantly better at 3 and 6 months than baseline (p = .0095 and p = .008, respectively) but not at 12 months (p = .065). In the PDT group, mean BCVA was +0.88 ± 0.45 logMAR at baseline, and improved to +0.85 ± 0.62 logMAR at 3 months and to +0.86 ± 0.44 logMAR at 6 months, which was not significantly different from baseline. Mean BCVA then decreased to +0.9 ± 0.54 logMAR at 12 months (p = .85). Mean logMAR VA was significantly better in the IVB group than in the PDT group after 3 months (p = .0043), 6 months (p = .0001) and 12 months (p = .0168). Mean CRT was significantly lower in IVB group than in PDT group at 3, 6 and 12 months (p = .008, p = .038, p = .040, respectively). Chorioretinal atrophy developed in six eyes (15%) treated with IVB and in 24 eyes (60%) treated with PDT at 12 months (p = 3.2 × 10(-5)). CONCLUSIONS: Over a 12-month period, intravitreal bevacizumab seems to be superior to photodynamic therapy in controlling myopic CNV in a North-African population.

Intravitreal bevacizumab for the treatment of choroidal neovascularization secondary to angioid streaks: one year of follow-up.

PURPOSE: To evaluate the efficacy and safety of intravitreal bevacizumab at one year follow-up, for the treatment of choroidal neovascularization (CNV) associated with angioid streaks. METHODS: A retrospective case series of eighteen eyes of 17 patients with CNV secondary to angioid streaks treated with intravitreal bevacizumab between October 2006 and May 2008. Ophthalmic evaluation including best corrected visual acuity (BCVA), slit lamp biomicroscopic examination, optical coherence tomography (OCT) and fluorescein angiography, was performed before and after treatment. Retreatment was given every 4-6 weeks in case of persistent symptoms or CNV activity on OCT. Main outcome measures were changes in BCVA and central retinal thickness on OCT. RESULTS: The mean number of injections was 4.8 at 1 year. Twelve eyes (66.6%) received five injections or more. The mean BCVA at baseline was 20/80 (range 20/400 to 20/32) and improved to 20/44 (range 20/160 to 20/20) at 1 year (p = 0.014). The BCVA improved by three or more lines in eleven eyes (61.11%) and remained within two lines of baseline in seven eyes (38.8%). Mean central retinal thickness was 404.2 µm (range 160-602 µm) at baseline and decreased to 300.5 µm (range 150-523 µm) at 1 year (p = 0.022). No ocular or systemic complications were noted. CONCLUSION: The 1-year outcomes suggest intravitreal bevacizumab to be a promising treatment for CNV associated with angioid streaks, resulting in both functional and anatomical improvements. Repeated injections are needed to maintain these results. Further long term studies are required to confirm these findings.

Optical Coherence Tomographic Findings in Berlin's Edema.

PURPOSE: To describe optical coherence tomography (OCT) findings in a patient with Berlin's edema following blunt ocular trauma. CASE REPORT: A 26-year-old man presented with acute loss of vision in his left eye following blunt trauma. He underwent a complete ophthalmologic examination and OCT. Fundus examination revealed abnormal yellow discoloration in the macula. OCT disclosed thickening of outer retinal structures and increased reflectivity in the area of photoreceptor outer segments with preservation of inner retinal architecture. Re-examination was conducted one month later at the time which OCT changes resolved leading to a surprisingly normal appearance. CONCLUSION: OCT can be a useful tool in the diagnosis and follow-up of eyes with Berlin's edema and may reveal ultrastructural macular changes.