Journal of Ophthalmic and Optometric Sciences
Volume:3 Issue: 3, Summer 2019

Keratoconus (KC) is a progressive eye condition marked by corneal protrusion, thinning, and scarring that adversely affects the ability to see and quality of life. A defective corneal extracellular matrix (ECM) assembly ultimately results in myopia, irregular astigmatism, and severe visual impairment. Most commonly occurring in adolescence, this condition is one of the most commonly indicated clinical indications for corneal transplantation. In contrast to corneal transplantation, corneal collagen crosslinking (CXL) increases corneal stiffness without inflicting any invasive surgery. This study used RNA-Seq data to investigate which functional genes are regulated by CXL in keratoconus. The RNA-Seq expression matrix related to individuals with Keratoconus (KC) and patients treated with collagen crosslinking (CXL) were obtained from the Gene Expression Omnibus (GEO)[1] database 1at the National Center for Biotechnology Information (NCBI) were retrieved. Differential expression analysis and functional enrichment analysis were conducted. The hub genes were then identified with the protein-protein interactions (PPI) network. Finally, transcription factor (TF) genes were identified that regulate these networks. We identified 126 genes in KC and CXL-treated patients that affect TF-mediated network adjustments that improve treatment. In addition, they may play a role in the pathogenesis of keratoconus. Visualization of the PPI networks enabled us to identify 63 highly connected (Hub) genes which served an essential biological function in regulatory networks.

To perform a comparison of axial length (AL) measurements using A-mode biometry, B-mode biometry and IOL Master.

Axial length among patients undergoing cataract surgery in Basir Eye Clinic, Tehran, Iran from May 2017 and September 2017 was determined pre-operatively using three methods. Axial length was first measured using IOLMaster 500 (Carl Zeiss Meditec, Jena, Germany), then by A-mode biometry using immersion technique and finally using horizontal axial B-scan immersion biometry. The interval between each examination was 5 minutes.

Statistical analysis revealed strong correlations between AL measurement values obtained from A-mode and B-mode (r = 0.983, P < 0.001), A mode and IOLMaster (r = 0.999, P < 0.001) as well as B-mode and IOLMaster (r = 0.984, P <0.001). All correlations were strong but the strongest correlation was observed between A mode and IOLMaster methods.

A-mode biometry showed a stronger correlation with IOL Master AL readings compared to B-Mode, thus when there are limited resources and the optical method is not accessible, A-mode immersion echography is proffered as an alternative to IOLMaster.

Keratoconus (KTCN, OMIM 148300) is known as an eye degenerative disease leading to stromal thinning and conical shape of the cornea. These structural changes can be accompanied by loss of visual function in advanced cases. To date, in spite of recent advances in the investigation of molecular mechanisms which result in Keratoconus, there’s still a lack of information about the role of miRNAs in this disorder. Accordingly, this study aims to find miRNA’s aberrantly expression in KTCN suffering cases and to predict their role by investigating their possible interactions with significantly KTCN correlated genes.

The RNA sequencing dataset was retrieved from GEO databases (http:// www.ncbi.nlm.nih.gov/geo). The data were comprised of 25 normal and 25 KTCN cases. Weighted gene co-expression network analysis approach was used to construct a protein-coding gene co- expression network and investigate the significant modules. Gene with the higher module membership (MM) and gene significance (GS) in the selected modules were supposed to be more KTCN relevant genes. Then CluGO plugin in Cytoscape software was used for enrichment analysis of genes in the selected modules. Differentially expressed genes in KTCN cases compared with normal cases were obtained using the edgeR package in R. All experimentally recorded miRNA-mRNA interactions were downloaded from miRTarbase database. Possible interactions from differentially expressed miRNAs and genes included in significant modules were retrieved.

Totally 2492 protein-coding genes (PCGs) and 99 miRNAs were up-regulated and 213 PCGs and 31 miRNAs were down-regulated. Significant correlation with the KTCN was observed in three modules, including brown, green-yellow, and salmon from the total of 15 modules. Genes in significant modules have been enriched to gene expression regulation related biological processes such as negative regulation of protein secretion, intra-Golgi vesicle-mediated transport, regulation of mRNA 3’-end processing, and cytoskeleton related gene ontologies such as modulation of the mitochondrial cytoskeleton. Up-regulated miRNAs that interact with down-regulated mRNAs within significant modules include miR-1305, miR-544a, miR-1245a, miR-4635, miR-4266.

Just as the results revealed most of the deregulated genes were involved in gene expression regulation processes. Therefore the de-regulated miRNAs might involve in the aberrant expression of their targets. In this case, mentioning miRNAs in the results section can be considered as potential diagnostic or therapeutic biomarkers for KTCN.

Glaucoma is recognized as one of the most common causes of global blindness observed in various types, such as primary open-angle glaucoma (POAG). This condition is characterized by progressive optic neuropathy, leading to the damage of optic nerve fibers. With no symptoms at the beginning, glaucoma results in decreased vision and eventually blindness over several years. Early treatment can prevent the progression of the disease.

The researchers performed a study to evaluate differential gene expression in normal control and POAG cases. A total of 179 DEGs were discovered with 60 up-regulated and 119 down-regulated genes. After the selection of DEGs, the protein-protein interaction network was constructed. The result of GO enrichment showed the DEGs were involved in antioxidant activity, haptoglobin binding, and oxygen carrier activity. Then four modules of the primary protein network were obtained using a STRING database, using the K-means method. Next, gene ontology analysis and Kyoto encyclopedia of genes and genomes pathway enrichment were performed for four modules.

The results showed that the selected module (Yellow module) is highly related to glaucoma pathogenesis genes. Among the genes identified in this module are TYRP1, FMOD, OGN, PAX6, COL8A2, HLA-DPA1, and HLA-DMB, which may be involved in the direct development of glaucoma.

Using integrated bioinformatical analysis, the researchers identified DEGs candidate genes and pathways involved in glaucoma, which improved our understanding of the cause and underlying molecular events. These candidate genes and pathways could be therapeutic targets for glaucoma.

Orbital emphysema is a benign and uncommon condition usually caused by a trauma-induced orbital wall fracture but in rare cases might happen after compressed air injury without orbital fracture. Here we present an 8-year-old patient with right eye swelling and redness after being exposed to explosion of an air pump compressor tube and was diagnosed with orbital emphysema.

A 16 year old female was referred to neurological clinic with diagnosis of papilledema for neurological evaluation. After consultation with us we became suspicious of pseudopapilledema according to refraction and biometric characteristics of the eye and the patient’s history. We performed fluorescein angiography for the patient. There was no leakage of fluorescein in images and papilledema diagnosis was rejected. The patient was diagnosed with crowded disc due to high hyperopia. This correction of diagnosis prevented the neurologist colleagues from developing the wrong diagnosis of papilledema caused by an intracranial mass, and performing any unnecessary investigations such as brain MRI or lumbar puncture.

To review etiologies, risk factors, management and prognosis of drug induced ectropion as a rare entity.

In this systematic review, we reviewed all related published articles in English literature until April 2019 by searching Pubmed resources using the keywords ‘drug induced ectropion’.

We found 26 relevant articles describing 48 patients with drug induced ectropion. The patient mean age was 67.4 years (range 15-93 years). Different topical and systemic drugs were reported as the causing agents including chemotherapeutic (45.8 %) drugs as the most frequent cause (22 patients, including 5 patients using topical fluorouracil, 9 patients using systemic fluorouracil, 7 patients using epidermal growth factor receptor inhibitors, and 1 patient using docetaxel), followed by topical anti-glaucoma (39.5 %) drugs (19 patients). The mean interval between starting the drug usage and emergence of ectropion was 9.74 months (range 1 day-72 months). Cessation of the causing drug and conservative treatments including topical lubricants, antibiotics and steroids were the most common management method. Surgery was required only in 10 patients (20.8 %).

Drug induced ectropion can develop following the administration of various topical and systemic drugs. Discontinuation of the causing drug and conservative treatments including topical steroids are often successful in managing the ectropion. Surgical treatment is scarcely needed among patients with drug induced ectropion.