Atypical case of choroidal osteoma associated to polypoidal choroidal vasculopathy and preretinal neovascular membrane.

PURPOSE: To report a very rare and atypical case of an elderly Caucasian female patient who developed perilesional multiple polypoidal choroidal vasculopathy (PCV) as a probable complication of choroidal osteoma (CO), associated to preretinal neovascular membrane overlying the lesion. METHODS: Observational case report. CASE OBSERVATION: A 60-year-old Caucasian woman presented with blurred vision in her right eye (RE). Fundus examination revealed a round white-yellowish calcified deep lesion in the juxta-papillary superior area, measuring 4 disc-diameters, with well-defined scalloped margins and an irregular surface. B-scan ultrasonography and orbital tomography confirmed the diagnosis of choroidal osteoma (CO). Further investigation with multimodal imaging including infracyanine green angiography, fluorescein angiography, swept source optical coherence tomography and angiography highlighted the presence of multiple aneurysmal choroidal dilations around the CO, corresponding to PCV. We also noted the presence of a preretinal neovascular membrane overlying the CO. The patient was monitored with regular follow-up since no signs of activity were detected on multimodal imaging. CONCLUSION: Our case report represents an exceptional and atypical association between pre-retinal neovascularization, PCV and choroidal osteoma. While the mechanisms underlying the development of PCV and pre-retinal neovascularization in the setting of CO are not well understood, it is imperative for ophthalmologists to recognize this association as a potential cause of sudden vision loss in patients with CO, and to consider appropriate diagnostic and management strategies.

Bilateral central retinal vein occlusion following COVID-19 vaccination: Cause or coincidence?

AIM: To report a case of sequential bilateral ischemic central retinal vein occlusion (CRVO) following the third dose of anti-COVID 19 vaccination. METHODS: Observational case report. RESULTS: A 73-year-old Caucasian male patient, with no known medical history, complained of sudden vision loss in his right eye (RE) 18 days following the third dose of Pfizer-BioNTech anti-COVID 19 vaccination. Ten days later, he suffered from sudden vision loss in his left eye (LE).Best-corrected visual acuity was limited to counting fingers at 50cm in both eyes.Fundus examination of both eyes revealed signs of ischemic central retinal vein occlusion (CRVO) with diffuse superficial and deep retinal hemorrhages in all four quadrants. Diagnosis was confirmed of fluorescein angiography.Optical coherent tomography (OCT) showed an ischemic hyperreflectivity and disorganization of the inner retinal layers in both eyes with significantly increased central macular thickness, associated to intraretinal fluid accumulation in LE.An urgent systemic assessment was requested. A mild hypertension was discovered and the rest of the work up was unremarkable. CONCLUSION: To our knowledge, we report the first case of bilateral CRVO in a healthy patient after anti-COVID 19 vaccination. CRVO occurred few days following third shot of vaccine followed by a sequential CRVO in the fellow eye in a patient with recently diagnosed very mild hypertension and no thrombo-embolic risk factors, strongly suggesting a relationship between both events. Nowadays, CRVO should be kept in mind as a potential side effect of Covid-19 vaccination and should be added to the spectrum of their ophthalmic complications.

Multimodal imaging of focal choroidal excavation and macular choroidal cavitation associated to choroidal neovascularization.

Purpose: To report multimodal imaging features of an unusual case of multiple focal choroidal excavations (FCE) associated to macular intrachoroidal cavitations (ICC) and choroidal neovascularization (CNV) in a non-myopic patient with normal choroidal thickness. Methods: Observational case report. Results: A 69-year-old non-myopic male patient with history of macular CNV of unknown etiology in the right eye (RE), initially treated with Bevacizumab intravitreal injections with significant improvement of visual acuity. He presented with acute vision loss in the same eye related to recurrent CNV exudation. Multimodal imaging of the RE confirmed the diagnosis of active type 2 CNV, associated to multiple FCE. Besides, it highlighted incidental unusual macular ICC in the same eye. Choroidal thickness was within normal limits (217 µm). Conclusion: Focal choroidal excavations and intrachoroidal cavitations can be observed in emmetropic patients in the absence of pachychoroid disease. In presence of CNV of unknown etiology, complete multimodal imaging can be of a great help to better define choroidal anomalies, allowing structural and vascular correlations between different lesions. Key words: Focal choroidal excavation; Choroidal cavitation; Multimodal imaging.

Atypical presentation of bilateral iridoschisis with abnormal visibility of iris vessels: Role of anterior segment optical coherence tomography.

PURPOSE: To describe clinical and anterior segment optical coherence tomography (AS-OCT) findings in a patient with bilateral iridoschisis and unilateral angle closure glaucoma (ACG) associated with abnormal visibility of iris vessels. CASE PRESENTATION: A 67-year-old male patient with a history of red and painful left eye (LE) one year earlier, presented to our ophthalmology department for a routine examination.Ophthalmic examination of the right eye revealed narrow anterior chamber with sectorial iris atrophy associated to abnormal visibility of an iris vessel. Intraocular pressure (IOP) was 12 mmHg with normal optic disc appearance. LE anterior chamber was narrow with diffuse iris atrophy and abnormal vessels visibility. IOP was 28 mmHg with an important optic disc excavation. On gonioscopy, angle was narrow without neovessels nor synechiae. AS-OCT of both eyes revealed shallow angles, iris splitting with material release in the anterior chamber, while pigmented epithelium was preservedAnti-glaucoma eye drops were prescribed and peripheral laser iridotomy was performed in both eyes with decreased IOP at 14 mmHg in the LE. CONCLUSION: Iridoschisis is a rare ocular condition characterized by a separation between the anterior and posterior layers of iris stroma with several clinical presentations, and may be associated with abnormal visibility of iris vessels in some cases. The diagnosis of iridoschisis may be challenging and AS-OCT can be a very useful tool to confirm the diagnosis in atypical presentations and to detect associated angle closure.

Central retinal artery occlusion after spinal surgery: Case report and literature review.

AIM: To report a rare case of unilateral central retinal artery occlusion (CRAO) following spinal surgery. METHODS: Observational case report. RESULTS: A 15-year-old female patient underwent scoliosis surgery under general anesthesia in a prone position, her head being supported by a horseshoe headrest for approximately four hours, with stable vitals and without significant blood loss during surgery. Upon waking up from general anesthesia, the patient immediately reported severe visual loss in her right eye (RE), associated to marked periocular ecchymosis and chemosis. Visual acuity was limited to light perception. Fundus examination showed normal optic disc appearance with diffuse retinal pallor and a macular cherry red spot. Optical coherence tomography (OCT) showed increased reflectivity in the inner retina, consistent with ischemic maculopathy in the RE. Brain and neck magnetic resonance imaging angiograms were unremarkable. Further investigations ruled out collagen vascular disease, Behcet disease, syphilis, sickle cell disease and hypercoagulable states. CONCLUSION: Central retinal artery occlusion is rarely observed following spinal surgery. The cause was presumed to be compression of the orbit by a horseshoe headrest in a prone position due to an accidental shift in position during surgery. This catastrophic complication, albeit rare, is usually irreversible and thus must be prevented. Proper positioning and vigilance by both the surgeon and the anesthesiologist during surgery are fundamental to ensure that the orbits are not under pressure.

Choroidal features in non-neovascular and neovascular pachychoroid diseases.

PURPOSE: To evaluate choroidal findings on multimodal imaging in eyes within pachychoroid spectrum diseases and to compare quantitative and qualitative choroidal features between non-neovascular (NNV-PDS) and neovascular (NV-PDS) pachychoroid diseases. METHODS: Retrospective cross-sectional study comparing between NV-PDS and NNV-PDS. All patients underwent multimodal imaging including infracyanine green angiography (IFCGA) and swept source optical coherence tomography (OCT) and angiography (OCT-A). The following parameters were analyzed: subfoveal choroidal thickness (SFCT), choroidal vascular index (CVI), presence of pachyvessels and choroidal vascular interconnections (CVIC), presence of choroidal neovascularization and choriocapillaris density. RESULTS: Of the 87 eyes included in the study, 63 eyes (73%) had NNV-PDS and 24 eyes (27%) had NV-PDS. Mean SFCT and CVI were significantly higher in NNV-PDS group (p = 0.01; p = 0.022). Pachyvessels were more diffusely distributed in NNV-PD group and more focally distributed in NV-PDS group (p = 0.029). CVIC were more frequently noted in NV-PDS group (p = 0.024). A higher CVI was associated to a thicker choroid (p < 0.001), with significant negative correlations between the presence of CVIC and both SFCT (p = 0.015) and CVI (p = 0.002). We also observed a lower choriocapillaris vascular density and higher number of choriocapillaris flow voids in eyes with NNV-PDS (p = 0.24; p = 0.61). CONCLUSION: NNV-PDS eyes had a significantly thicker SFCT, higher CVI and a lower rate of detected CVIC than eyes with NV-PDS. These highlighted choroidal vascular changes might lead to a better understanding of pachychoroid disease pathophysiology. More frequently observed in NV-PDS group, CVIC are believed to assess the development of vortex vein anastomoses as a remodelling process for vascular decongestion.

Optical coherence tomography and angiography in Alzheimer's disease and other cognitive disorders.

AIMS: The aims of this study were to analyze retinal and choroidal changes on optical coherence tomography (OCT) and OCT-Angiography (OCT-A) in Alzheimer's disease (AD) patients and compare them to other forms of major dementia. We also aimed to analyze the correlation between clinical severity of global cognitive deficiency assessed by the mini-mental state exam (MMSE) score and OCT/OCT-A parameters. METHODS: Retrospective cross-sectional evaluative study of AD, and age-and gender-matched patients with other dementias. Fundus examination, OCT and OCT-A were compared. RESULTS: Ninety-one eyes of AD patients and 53 eyes of patients with other dementias were included. Retinal deposits were found in 6.59% of AD cases. OCT highlighted the presence of hyperreflective deposits and localized areas of outer retina and ellipsoid zone disruption, respectively in 20.87% and 15.38% of AD cases. Hyperreflective foci were noted within inner retinal layers in 4.39% of AD cases. Quantitative analysis revealed a thicker nasal retinal nerve fiber layer (p = 0.001) and ganglion cell complex in superior (p = 0.011) and temporal quadrants (p = 0.009) in eyes of AD patients, compared to other dementias. OCT-A showed a significantly higher fractal dimension of both superficial and deep capillary plexus (p = 0.005), with lower choriocapillaris density (p = 0.003) in AD patients. CONCLUSIONS: Structural OCT could highlight the presence of hyperreflective deposits in AD, probably reflecting beta-amyloid deposits, associated to outer retinal disruptions. Quantitative OCT analysis showed structural differences between AD patients and other dementias, and combined OCT-A could identify microvascular changes in AD patients representing new potential differential diagnosis criteria.

Optic disc and choroidal metastases secondary to breast cancer: A case report.

AIM: To report an uncommon case of optic disc and multiple choroidal metastases secondary to breast cancer, assessed with swept source optical coherence tomography (SS-OCT), fluorescein (FA), and infracyanine (ICGA) angiographies. METHODS: Observational case report. CASE PRESENTATION: A 40-year-old woman with history of left breast carcinoma presented with blurred vision in her right eye (RE). Her visual acuity was 1/20 in the RE and 10/10 in the left eye. Fundus examination of the RE showed a large yellowish elevation of the posterior pole and a particular whitish nodular papillary cluster protruding from the optic disc into the vitreous. Infrared imaging enhanced the papillary nodular infiltrates. Characteristic findings of choroidal metastasis were noted within the macular lesion on SS-OCT and ICGA. SS-OCT showed specific "lumpy bumpy" irregularity of the anterior surface of the choroid and elevated hyperreflective nodular lesions of the optic disc associated to peripapillary subretinal fluid. The papillary lesions appeared as a bunch of hypofluorescent dots on both FA and ICGA, and ultra-wide field FA was helpful clearly delimiting the large macular lesion. Besides, comprehensive imaging and especially ICGA could detect two asymptomatic choroidal metastases in a systematic assessment of the fellow eye. CONCLUSION: Optic disc metastases are extremely rare. Their diagnosis can be easily done on fundus examination when presenting with characteristic whitish cluster nodular infiltrates of the optic disc. However multimodal imaging remains very useful for the assessment of the local extension of the lesion and for diagnosing associated asymptomatic choroidal lesions gone unnoticed at the fundus examination.

Multimodal imaging of bilateral immunogammopathy maculopathy associated to Waldenström's macroglobulinemia.

AIM: Our aim is to report a case with bilateral Waldenström's macroglobulinemia (WM) associated maculopathy, assessed with multimodal imaging including swept source optical coherence tomography (SS-OCT) and OCT-Angiography (OCT-A). METHODS: Observational case report. CASE PRESENTATION: A 61-year-old diabetic woman with history of treated WM currently in remission, presented with progressive bilateral visual loss. Best-corrected visual acuity was 20/100 in the right eye (RE) and 20/200 in the left eye (LE). Fundus examination showed bilateral microaneurysms and retinal punctuate hemorrhages and a large macular serous detachment in the LE. There was no retinal ischemia on FA nor macular dye leakage. SS-OCT showed a significant schisis-like intraretinal fluid accumulation in the RE and a large prominent macular detachment with significant subretinal fluid accumulation in the LE. Retinal and choriocapillaris vascular densities were normal on OCT-A. CONCLUSION: Our case illustrated characteristic multimodal imaging findings in WM associated maculopathy such as schisis-like intraretinal fluid accumulation and angiographically silent serous macular detachment. OCT-A could non-invasively analyze macular vascular densities layer-by-layer, without noticing any vascular anomaly.

FOCAL CHOROIDAL THICKNESS HEMODYNAMICS AS a SIGN OF MACULAR NEOVASCULARIZATION ACTIVITY IN PATHOLOGIC MYOPIA.

PURPOSE: To analyze the relationship between a focal increase of choroidal thickness (ChT) and exudative activity of macular neovascularization (MNV) secondary to pathologic myopia. METHODS: Retrospective analysis including eyes with pathologic myopia presenting with a focally increased ChT underneath active MNV. All patients included were treated, and ChT was measured before and after each intravitreal injection by two experienced ophthalmologists. RESULTS: Fifty-two eyes of 52 patients with myopic MNV (19 men and 33 women) were included in this analysis. ChT at T-1 averaged 51.09 ± 33.56 µ m, whereas at the time of MNV activation (T0), ChT was significantly thicker: 85.11 ± 43.99 µ m ( P < 0.001). After a single intravitreal injection, the ChT significantly decreased to 53.23 ± 34.15 µ m ( P < 0.001). CONCLUSION: This study showed that focal ChT variations may be considered an interesting corollary sign of MNV in high myopic patients, indicating the activity of myopic neovascularization.

Management of a Bilateral Post-Uveitic Complex Glaucoma with Pupillary Block, Rupture of the Anterior Lens Capsule, and Malignant Glaucoma following Laser Peripheral Iridotomies: Case Report and Literature Review.

Purpose: To report a case of a bilateral complex uveitic glaucoma (UG) with pupillary block, rupture of the anterior lens capsule, and malignant glaucoma in a young high-myopic patient and to report anterior segment optical coherence tomography (AS-OCT) findings initially and following surgery. Methods: A 21-year-old high-myopic woman who had a history of anterior uveitis with extensive posterior synechiae, presented with acute bilateral ocular pain, redness, and blurred vision following bilateral Nd: YAG laser peripheral iridotomy (LPI). Results: Visual acuity was limited to light perception in both eyes (OU), with a flat anterior chamber (AC) and anterior luxation of lens fragments. Intraocular pressure (IOP) was over 60 mmHg OU. AS-OCT showed closed angles and hyperreflective heterogeneous material within the flat AC. The iris and lens fragments were plated against the corneal endothelium OU. We performed an urgent pars plana vitrectomy associated with lensectomy. It was uneventful in OU. Repeated AS-OCT revealed a deep AC, widely open angles, and aphakia. IOP was lowered to 9 mmHg and visual acuity improved to 5/10 in OU. Conclusion: Performing LPI might be harmful in the presence of UG with extensive posterior synechia, resulting in complex mechanism glaucoma with aqueous misdirection syndrome associated with a pupillary block due to anterior lens luxation, even in high-myopic eyes. Nd: YAG LPI should not be performed simultaneously in OU, especially in pathologic eyes, to prevent bilateral vision-threatening complications. AS-OCT was of great help, allowing easy and detailed ultrastructural assessment of the ACs, and iridocorneal angles before and after surgery.

Case Report: Swept-source Optical Coherence Tomography and Angiography Findings in Lipemia Retinalis.

SIGNIFICANCE: Lipemia retinalis is a very rare ocular manifestation of severe hypertriglyceridemia. It is usually symptomatic and regresses after normalization of triglycerides levels. Early recognition is important to prevent ocular and life-threatening complications. PURPOSE: This study aimed to report a case of marked lipemia retinalis secondary to type V hypertriglyceridemia assessed with swept-source optical coherence tomography (OCT) and OCT angiography (OCT-A), with follow-up after dietary lipid restriction. METHODS: Observational case report of lipemia retinal findings on color fundus photography, swept-source OCT and OCT-A, initially and after triglycerides lowering. CASE REPORT: A 32-year-old pregnant patient with gestational diabetes and a history of hypertriglyceridemia was referred for diabetic retinopathy screening. Fundus examination revealed bilateral milky-white discoloration of retinal vessels with a "salmon-colored" retina. Swept-source OCT and OCT-A revealed extremely hyperreflective and dilated retinal vessels and multiple high-flow retinal hyperreflective dots, corresponding to dilated retinal capillaries. Choroidal vessels were enlarged and engorged, and choriocapillaris layer appeared thickened and hyperreflective with dilated and tortuous capillaries. Serum triglycerides were very high (70.02 mmol/L). After 21 days of very-low-fat diet, it was lowered to 15 mmol/L. We noted a normalization of the clinical, structural, and vascular findings. However, peripheral retinal vessels remained hyperreflective, despite their clinical normalization. CONCLUSIONS: Swept-source OCT and OCT-A were beneficial in assessing lipemia retinalis noninvasively and monitoring choroidal and retinal vascular changes. Lipemia retinalis signs regressed initially in the posterior pole, choroidal anomalies were first to resolve, and clinical normalization preceded tomographic resolution.

OCT-angiography assessing quiescent and active choroidal neovascularization in retinitis pigmentosa associated with PRPH2 pathogenic variant.

PURPOSE: To report multimodal imaging findings including optical coherence tomography angiography (OCT-A) of a patient presenting with a quiescent choroidal neovascularization (CNV) in one eye and an active CNV in the fellow eye, complicating retinitis pigmentosa (RP) linked to PRPH2 pathogenic variant, with follow-up and management of both eyes. METHODS: Observational case report. RESULTS: A 40-year-old female with history of autosomal dominant RP consulted for acute visual loss in her right eye (RE). Multimodal imaging including OCT-A confirmed the diagnosis of active type 2 CNV in the RE and highlighted an incidental asymptomatic non-exudative "quiescent" CNV in the left eye (LE). This complication was managed by intra-vitreal Bevacizumab injections in the RE and regular monitoring of the LE. Frequent follow-up could detect early CNV activation signs in LE allowing early treatment. Mutation analysis of PRPH2 exons identified a known heterozygous pathogenic missense variation c.646C>T, p.P216S in exon 2. CONCLUSION: Multimodal imaging and especially OCT-A can be of a great help in the diagnosis and the management of CNV complicating RP, even at the stage of quiescent CNV. In presence of neovascular complication, PRPH2 gene should be investigated because of its frequent macular involvement despite high phenotypic variability.

Irregular vascular network identified with OCT-A in angioid streaks: A probable predictor of active choroidal neovascularization (case series).

PURPOSE: To evaluate the risk of active choroidal neovascularization (CNV) in presence of deep irregular vascular network (IVN) in eyes with angioid streaks (AS). METHODS: Observational case series including three treatment-naive eyes with angioid streaks and IVN, without CNV. Patients were followed-up during 18 months with multimodal imaging including structural optical coherence tomography (OCT) and OCT Angiography (OCT-A) to detect possible neovascular complication. RESULTS: On OCT-A, IVN was detected as a peripapillary and/or macular high-flow lesion, filling the spaces between the angioid streaks in the outer retina slab. Repeated OCT-A could detect an active CNV emerging from the IVN, as a high-flow rich anastomotic vascular network with a perilesional dark halo. Patient was treated with intravitreal injections of Bevacizumab on a Pro Re Nata regimen, with a decreased CNV area and lower vascular density on control OCT-A. CONCLUSION: OCT-A shown to be helpful in detecting the presence of IVN in asymptomatic eyes with AS during a routine examination. In our series, the IVN seems to be predictor of active CNV, needing a close surveillance and frequent follow-up to allow early treatment upon CNV activation.

Swept source OCT-Angiography assessing a case of aneurysmal type 1 neovascularization secondary to high-myopic posterior staphyloma.

AIM: To report an uncommon case of aneurysmal type 1 neovascularization (polypoidal choroidal vasculopathy) secondary to high-myopic staphyloma in a Caucasian patient, assessed with multimodal imaging including swept source OCT-Angiography. METHODS: Observational case report. RESULTS: About 73-year-old Caucasian male patient with high myopia (axial length = 27.24 mm). Fundus examination showed a myopic conus and a deep orange-brownish nodular lesion at the edge of a deep haemorrhage and connected to a large choroidal vessel. ICGA showed a circular hyperfluorescent lesion in mid-phase, without any branching vascular network. OCT-Angiography could detect the aneurysmal lesion non-invasively as a small circular high-flow lesion in the outer retina slab, with a shadowing in the choriocapillaris slab. At the level of the aneurysmal lesion, structural OCT showed a high bilobed PED, without any subretinal fluid. A vascular flow was noted within the PED on cross-sectional OCT-A, confirming the vascular aneurysmal nature of this lesion. Additionally, swept source OCT highlighted the presence of an abrupt change in choroidal thickness, from 62 µm in the peripapillary area to 120 µm underneath the polypoidal lesion, with dilated choroidal vessels. CONCLUSION: To our knowledge, this is the first report of OCT-A findings in aneurysmal (polypoidal) dilation secondary to high-myopic staphyloma. We could demonstrate the usefulness of OCT-A detecting non-invasively the aneurysmal dilation and the usefulness of swept source OCT assessing the choroidal structure to better understand the pathophysiology of this uncommon finding.

Macular Dystrophy with Bilateral Macular Telangiectasia Related to the CYP2U1 Pathogenic Variant Assessed with Multimodal Imaging Including OCT-Angiography.

PURPOSE: We report the case of a neurologically asymptomatic young boy presenting with an unusual phenotype of CYP2U1 related macular dystrophy associating bilateral macular telangiectasia (MacTel) and fibrotic choroidal neovascularization (CNV), assessed with complete multimodal imaging including optical coherence tomography angiography (OCT-A). CASE PRESENTATION: A twelve-year-old boy from a non-consanguineous family complained of bilateral progressive visual loss and photophobia. The best-corrected visual acuity was 2/10 on the right eye and 3/10 on the left eye. Fundus examination showed central pigmented fibrotic macular scar and yellowish punctuate deposits in both eyes. En face OCT-A detected typical macular telangiectasia (MacTel) in both eyes with dilated telangiectatic capillaries in the deep capillary plexus associated with vascular anomalies in the superficial and deep capillary plexus. Typical hypo-reflective cavities were observed within the inner foveal layers on structural OCT. En face OCT-A also confirmed the presence of bilateral inactive CNV within the fibrotic scars, showing high-flow vascular network at the level of the subretinal hyperreflective lesions. Whole exome sequencing identified a known homozygous pathogenic variant in CYP2U1 gene (c.1168C > T, p.Arg390*), which is a disease-causing mutation in autosomal recessive spastic paraplegia type 56 (SPG56). The neurological examination was normal, and electromyography and brain magnetic resonance imaging were unremarkable as well. CONCLUSION: Macular dystrophy can be the first manifestation in SPG56. A particular phenotype with MacTel was observed, and neovascular complications are possible. CYP2U1 should be included in the panels of genes tested for macular dystrophies, especially in the presence of MacTel and/or neurological manifestations.

Subthreshold micropulse laser adjuvant to bevacizumab versus bevacizumab monotherapy in treating diabetic macular edema: one- year- follow-up.

PURPOSE: To compare the therapeutic impact of combining intravitreal injections of bevacizumab (IVB) with micropulse laser (MPL) in central diffuse diabetic macular edema (DME) versus IVB monotherapy during 12 months follow-up. METHODS: We conducted a retrospective comparative study of 98 treatment-naive eyes (63 patients) with central diffuse DME. The first group of patients (IVB + MPL group, n = 49) was treated with 3 monthly IVB followed by MPL within 1 week after the third injection. Patients were then followed and treated on a pro re nata (PRN) basis, with MPL retreatment if necessary. The changes in best-corrected visual acuity (BCVA), central macular thickness (CMT), number of IVB injections and MPL sessions were evaluated at 4, 8, and 12 months. A control group of diabetic patients with treatment-naive DME was treated with standard protocol of 3 monthly IVB as monotherapy then followed on a PRN basis (IVB group, n = 49). Statistic comparaison of BCVA, CMT, and IVB number variation was interpreted at 12 months between both groups. RESULTS: In IVB + MPL group, baseline BCVA improvement was not significant at 4 and 8 months (p = 0.90, p = 0.08), and was statistically significant (p = 0.01) at 12 months. Mean CMT significantly decreased at 4, 8, and 12 months (p < 0.01) in IVB + MPL group. The difference in BCVA (p = 0.091) and CMT (p = 0.082) variation at 12 months between both groups was not significant but the number of injections was significantly lower in IVB + MPL group (4.1 ± 1.5 injections) compared to IVB group (7.2 ± 1.3 injections) (p < 0.005). CONCLUSION: Combining intravitreal injections of bevacizumab and MPL in the treatment of DME is effective and safe. This protocol may decrease the number of IVB and its frequency. It offers the advantage of lasting therapeutic response with fewer recurrences.

E-learning for Ophthalmology Training Continuity During COVID-19 Pandemic: Satisfaction of residents of Hédi Raies Institut of Ophthalmology of Tunis.

INTRODUCTION: COVID-19 pandemic created great challenges for the continuity of medical education. At the Hédi Raies Institut of Ophthalmology of Tunis (HRIO), the need to ensure continuity in the teaching of ophthalmology has stimulated the development of a new e-learning resource based on clinical case studies. AIM:   To evaluate level of satisfaction of HRIO residents in regard to clinical case-study-based e-learning of ophthalmology. METHODS: Cross-sectional survey including 40 ophthalmology residents doing their internship at the ROHI during the first half of 2020. Learners were tutored in e-learning via the Moodle online learning platform and using a problem-solving format based on clinical case studies describing various ophthalmologic conditions. Data collection was carried out through an online survey after four months of training, designed to assess learners' satisfaction with the e-learning. RESULTS: Mean age of participants was 29.95 ± 1.73 years. The majority had found the navigation easy, the content relevant to their training objectives, and were satisfied with the discussion forums as a method of communication. All respondents were satisfied with clinical cases presented through the platform and felt that they helped them to better understand the content. Among them, 97.5% considered that this teaching method corresponded to their training needs. There was a statically significant difference in the level of knowledge before and after e-learning teaching, taking into account the residents' appreciation (p<0.001). CONCLUSIONS: This study highlights the importance of virtual learning in ophthalmology in the era of the COVID-19 pandemic. E-learning is well appreciated by ophthalmology residents, relatively easy to integrate to their training program, and reduces issues of time, patient availability and case exposure.

Central corneal thickness in a healthy Tunisian population.

AIM: To study the central corneal thickness of a Tunisian population and determine the influence of age, gender, axial length and refractive error on central corneal thickness (CCT) values. METHODS: An observational, cross-sectional study was conducted on 608 eyes of consecutive Tunisian patients without ophthalmic disease. Corneal tomography (Oculus Pentacam, USA) and a complete eye examination were performed on all patients. The relationship between the central corneal thickness values and variables of age, refractive error, axial length and gender was assessed. RESULTS: The mean central corneal thickness was 522±37.17µm (range 461 to 655 µm). No statistical association was found between central corneal thickness values and variables of age, refractive error, axial length and gender. CONCLUSIONS: The normal CCT value in the Tunisian population was of 522±37.17 µm. We have analyzed, for the first time, normal central corneal thickness values of a healthy Tunisian population.

Homozygous mutation in ABCA4 associated with cone rod dystrophy in a patient with Turner syndrome.

PURPOSE: We report a special case of a patient who presented with two rare genetic diseases, Turner syndrome and cone-rod dystrophy (CRD), caused by mutation in the ABCA4 gene. METHODS: We present a case of a 12-year-old female with a progressive visual loss, poor night vision and short stature. We performed a clinical, karyotype of peripheral blood and molecular genetic study. DNA sample from the index patient was subjected to whole exome sequencing. Variants localized in homozygous regions were validated by Sanger sequencing. RESULTS: Fundus examination presented CRD phenotype and the general examination revealed short stature, aortic coarctation and infantile uterus, without visible ovaries on pelvic ultrasound. The karyotype of peripheral blood showed monosomy 45,X. We identified a known homozygous deletion c.[885delC];[885delC] in ABCA4, resulting in a frameshift at the position p.[L296Cfs*4];[ L296Cfs*4] . In addition, mutations in RPGR and ORF15 were excluded. CONCLUSIONS: Several ocular disorders are known to be associated with Turner syndrome, however, in this case, we hypothesize that CRD is not related to Turner syndrome but may be a manifestation of the lack of a normal X chromosome with ABCA4 mutation.