Search

PurposeThe purpose of this study was to compare the natural history of visual function change in cohorts of patients affected with retinal degeneration due to biallelic variants in Bardet-Biedl syndrome genes: BBS1 and BBS10.MethodsPatients were recruited from nine academic centers from six countries (Belgium, Canada, France, New Zealand, Switzerland, and the United States). Inclusion criteria were: (1) female or male patients with a clinical diagnosis of retinal dystrophy, (2) biallelic disease-causing variants in BBS1 or BBS10, and (3) measures of visual function for at least one visit. Retrospective data collected included genotypes, age, onset of symptoms, and best corrected visual acuity (VA). When possible, data on refractive error, fundus images and autofluorescence (FAF), optical coherence tomography (OCT), Goldmann kinetic perimetry (VF), electroretinography (ERG), and the systemic phenotype were collected.ResultsSixty-seven individuals had variants in BBS1 (n = 38; 20 female patients and 18 male patients); or BBS10 (n = 29; 14 female patients and 15 male patients). Missense variants were the most common type of variants for patients with BBS1, whereas frameshift variants were most common for BBS10. When ERGs were recordable, rod-cone dystrophy (RCD) was observed in 82% (23/28) of patients with BBS1 and 73% (8/11) of patients with BBS10; cone-rod dystrophy (CORD) was seen in 18% of patients with BBS1 only, and cone dystrophy (COD) was only seen in 3 patients with BBS10 (27%). ERGs were nondetectable earlier in patients with BBS10 than in patients with BBS1. Similarly, VA and VF declined more rapidly in patients with BBS10 compared to patients with BBS1.ConclusionsRetinal degeneration appears earlier and is more severe in BBS10 cases as compared to those with BBS1 variants. The course of change of visual function appears to relate to genetic subtypes of BBS.

Cataract, the loss of ocular lens transparency, accounts for ∼50% of worldwide blindness and has been associated with water and solute transport dysfunction across lens cellular barriers. We show that neutral amino acid antiporter LAT2 (Slc7a8) and uniporter TAT1 (Slc16a10) are expressed on mouse ciliary epithelium and LAT2 also in lens epithelium. Correspondingly, deletion of LAT2 induced a dramatic decrease in lens essential amino acid levels that was modulated by TAT1 defect. Interestingly, the absence of LAT2 led to increased incidence of cataract in mice, in particular in older females, and a synergistic effect was observed with simultaneous lack of TAT1. Screening SLC7A8 in patients diagnosed with congenital or age-related cataract yielded one homozygous single nucleotide deletion segregating in a family with congenital cataract. Expressed in HeLa cells, this LAT2 mutation did not support amino acid uptake. Heterozygous LAT2 variants were also found in patients with cataract some of which showed a reduced transport function when expressed in HeLa cells. Whether heterozygous LAT2 variants may contribute to the pathology of cataract needs to be further investigated. Overall, our results suggest that defects of amino acid transporter LAT2 are implicated in cataract formation, a situation that may be aggravated by TAT1 defects.

We report a three-generation family with isolated Alport-like retinal abnormalities in the absence of lenticonus, hearing loss, kidney disease, and detectable molecular genetic defects in known Alport-related genes. Clinical examination includes ocular biomicroscopy, fundus photography, optical coherence tomography, dipstick urinalysis, serum creatinine assessment, and molecular genetic analysis. The proband, her mother, and her maternal grandmother had normal best-corrected visual acuity and normal visual fields in both eyes. The macula presented a petaloid stair-case profile with scarce vessels in both eyes of the proband and a flat temporal macula lacking a foveal avascular zone in her mother and her grandmother. No family member had renal symptoms, unexplained subnormal hearing, or lenticonus. Sequencing and MLPA found no defect in COL4A3, COL4A4, and COL4A5. Common SNPs around the genes ± 1Mb showed no segregation. Furthermore, none of the variants shared between the affected individuals in genes from a gene panel of genes relevant for ophthalmopathy nor whole exome- and genome sequencing explained the phenotype. A new condition with two retinal Alport-like phenotypes was found. No abnormalities of the kidneys and lens were found, neither abnormalities of the type IV collagen genes related to Alport syndrome. Homology with retinal abnormalities seen in patients after surgical removal of the inner limiting membrane of the retina suggests that this is where the defect is located. We therefore suggest that the new retinal phenotypes and similar phenotypes can be described with the new definition "frail inner limiting membrane maculopathy." [ABSTRACT FROM AUTHOR]

Background In intra-arterial chemotherapy for retinoblastoma, a backflow from unreachable external carotid artery branches in the ophthalmic artery can be challenging. Objective To describe a new endovascular technique using Gelfoam pledgets to temporarily occlude distal branches of the external carotid artery to reverse the competitive backflow into the ophthalmic artery in order to perform intra-arterial chemotherapy via the ostium of the ophthalmic artery in selected cases. Methods We queried our prospectively collected database of 327 consecutive patients treated for retinoblastoma by intra-arterial chemotherapy and identified those employing Gelfoam pledgets. We describe this new technique with emphasis on feasibility and safety. Results We treated 11 eyes with 14 infusions of intra-arterial chemotherapy using Gelfoam pledgets to occlude the distal branches of the external carotid artery. We report no perioperative complications due to this occlusion technique. At the ophthalmologic follow-up 1 month after the injection of Gelfoam pledgets, all cases showed tumor regression or stable disease. Two injections into the same eye as the rescue intra-arterial chemotherapy infusion resulted in a transient exudative retinal detachment, and one injection in a heavily pretreated case was followed by iris neovascularization and retinal ischemia. None of the pledget injections led to irreversible vision-threatening intraocular complications. Conclusions Intra-arterial chemotherapy in retinoblastoma using Gelfoam to transiently occlude the distal branches of the external carotid artery and reverse the backflow into the ophthalmic artery seems feasible and safe. Larges series will help to confirm the effectiveness of this new technique. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigates the adverse effects of selective intra-arterial chemotherapy (SIAC) on the eyes and optic nerves of retinoblastoma patients using magnetic resonance imaging (MRI). We aim to understand the post-SIAC changes in orbital and ocular structures and evaluate their impact on eye and optic nerve growth. Experienced radiologists analyzed MR images of retinoblastoma eyes treated with SIAC, comparing them to eyes treated with other eye-saving methods and healthy eyes. Results reveal common adverse effects like inflammation and vascular changes, along with significant ocular growth arrest and optic nerve atrophy in eyes treated with SIAC, especially in children treated ≤ 12 months of age. This study underscores the importance of careful consideration when utilizing SIAC, particularly in young patients, due to its potential negative effects on eye and optic nerve development. This retrospective multicenter study examines therapy-induced orbital and ocular MRI findings in retinoblastoma patients following selective intra-arterial chemotherapy (SIAC) and quantifies the impact of SIAC on ocular and optic nerve growth. Patients were selected based on medical chart review, with inclusion criteria requiring the availability of posttreatment MR imaging encompassing T2-weighted and T1-weighted images (pre- and post-intravenous gadolinium administration). Qualitative features and quantitative measurements were independently scored by experienced radiologists, with deep learning segmentation aiding total eye volume assessment. Eyes were categorized into three groups: eyes receiving SIAC (Rb-SIAC), eyes treated with other eye-saving methods (Rb-control), and healthy eyes. The most prevalent adverse effects post-SIAC were inflammatory and vascular features, with therapy-induced contrast enhancement observed in the intraorbital optic nerve segment in 6% of patients. Quantitative analysis revealed significant growth arrest in Rb-SIAC eyes, particularly when treatment commenced ≤ 12 months of age. Optic nerve atrophy was a significant complication in Rb-SIAC eyes. In conclusion, this study highlights the vascular and inflammatory adverse effects observed post-SIAC in retinoblastoma patients and demonstrates a negative impact on eye and optic nerve growth, particularly in children treated ≤ 12 months of age, providing crucial insights for clinical management and future research. [ABSTRACT FROM AUTHOR]

Introduction: Mutational screening of inherited retinal disorders is prerequisite for gene targeted therapy. Our aim was to report and analyze the proportions of mutations in inherited retinal disease (IRD)-causing genes from a single center in Switzerland in order to describe the distribution of IRDs in Western Switzerland. Methods: We conducted a retrospective study of patient records. Criteria for inclusion were residence in Western Switzerland for patients and relatives presenting a clinical diagnosis of IRDs and an established molecular diagnosis managed by the genetics service of the Jules-Gonin Eye Hospital (JGEH) of Lausanne between January 2002 and December 2022. We initially investigated the IRD phenotypes in all patients (full cohort) with a clinical diagnosis, then calculated the distribution of IRD gene mutations in the entire cohort (genetically determined cohort). We analyzed a sub-group that comprised pediatric patients (≤18 years of age). In addition, we calculated the distribution of gene mutations within the most represented IRDs. Comprehensive gene screening was performed using a combined approach of different generation of DNA microarray analysis, direct sequencing, and Sanger sequencing. Results: The full cohort comprised 899 individuals from 690 families with a clinical diagnosis of IRDs. We identified 400 individuals from 285 families with an elucidated molecular diagnosis (variants in 84 genes) in the genetically determined cohort. The pediatric cohort included 89 individuals from 65 families with an elucidated molecular diagnosis. The molecular diagnosis rate for the genetically determined cohort was 58.2% (family ratio) and the 5 most frequently implicated genes per family were ABCA4 (11.6%), USH2A (7.4%), EYS (6.7%), PRPH2 (6.3%), and BEST1 (4.6%). The pediatric cohort had a family molecular diagnosis rate of 64.4% and the 5 most common mutated genes per family were RS1 (9.2%), ABCA4 (7.7%), CNGB3 (7.7%), CACNA1F (6.2%), CEP290 (4.6%). Conclusions: This study describes the genetic mutation landscape of IRDs in Western Switzerland in order to quantify their disease burden and contribute to a better orientation of the development of future gene targeted therapies. [ABSTRACT FROM AUTHOR]

Aims To report long-term results of intracameral chemotherapy (ICC) for aqueous seeding (AS) in retinoblastoma. Methods Retrospective study including 20 patients with primary (n=4) or secondary non-iatrogenic (n=16) AS treated with ICC according to a previously described technique between 2011 and 2020 with at least 1-year follow-up. Results AS control was initially achieved in all cases with a mean 5 injections of melphalan (n=13) or topotecan (n=7). Three eyes had an isolated AS relapse at a mean interval of 8 months after the first ICC course, which regressed with a second course of intracameral melphalan. Concomitant interciliary process seed implantation was treated with additional brachytherapy if sectorial (n=3) or proton therapy if annular (n=1). Other therapies including systemic, intra-arterial chemotherapy and/or focal treatments were given in 15 eyes to treat concomitant tumour sites. Eye preservation was achieved in 85% of the eyes (n=17/20) at a mean event-free follow-up of 45 months for aqueous disease, and 40 months for any other intraocular tumour activity. Three cases were enucleated due to refractory non-aqueous disease. All patients are alive without metastasis (mean follow-up of 48 months after first ICC). ICC-related intraocular toxicity included iris atrophy (n=5), cataract (n=4), posterior synechiae (n=2) and iris heterochromia (n=1). No patient suffered irreversible vision loss. Useful to normal vision was found in 82% of the cases (n=14/17). Conclusion ICC appears to be safe and efficient for AS without irreversible vision-threatening adverse effects. More data are needed to determine any superiority in efficiency/toxicity of topotecan versus melphalan. [ABSTRACT FROM AUTHOR]

One case (case #4) with no light perception at diagnosis had refractory glaucoma despite five goniosynechialyses and a 180° cyclocryocoagulation treatment combined with a three-drug topical anti-glaucoma therapy. In retinoblastoma, the management of glaucoma should always be preceded by the necessity to provide the appropriate tumour treatment and save the life of the patient. Two cases (case #1 and #2) received further tumour treatments after the glaucoma surgery. [Extracted from the article]