Journal of Ophthalmic and Vision Research
Volume:16 Issue: 4, Oct-Dec 2021

To investigate changes in meibomian gland morphology and impact of electronic device usage time on meibomian glands in pediatric age group.

In this prospective study, 149 eyes of 149 children were enrolled. The participants also completed the Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire and provided information regarding weekly hours spent in front of a digital screen. Meibography was performed in all subjects. Grading of images was evaluated using a previously validated 5-point meiboscale (0–4) for meibomian gland atrophy and a 3-point scale for meibomian gland tortuosity (0–2).

Of the 149 enrolled children, 83 (55.7%) were female and 66 (44.3%) male. The mean age was 13.0 ± 3.0 (range, 5–18) years. The mean loss of meibomian gland area was 20.80 ± 9.32%. The mean meiboscore was 1.20 ± 0.58 for gland atrophy and the mean tortuosity score was 0.99 ± 0.62. The mean screen time was 29.32 ± 16.18 hr/week. There was a weak and significantly positive correlation between loss of meibomian gland area and screen time (r = 0.210, P = 0.010). There was a weak and significantly positive correlation between meiboscore for gland atrophy and screen time (r = 0.188, P = 0.022). We found a weak but significantly positive correlation between meibomian gland tortuosity and screen time (r = 0.142, P = 0.033).

Meibomian gland morphology may show changes in pediatric age group and excessive screen time may be a factor triggering these changes in gland morphology

To assess contrast sensitivity in clear and colored soft contact lenses under different lighting conditions.

This study was performed on 34 medical students. Visual acuity was measured using a tumbling E chart at a distance of 6 m, and contrast sensitivity was determined by Pelli Robson chart at a distance of 1 m. These tests were repeated in mesopic (3 lux) and glare (2000 lux) conditions. Then, a clear contact lens was applied to one eye and a colored contact lens was applied to the other. After 2 hr, visual acuity and contrast sensitivity were measured for each individual. The results were compared with and without contact lenses under normal, mesopic, and glare conditions.

The mean refractive error was 0.44 ± 0.20 diopters. Repeated measures ANOVA showed a decline in contrast sensitivity with colored and clear contact lenses as compared to no-lens condition (P < 0.001). Additionally, lighting conditions had a significant impact on contrast sensitivity (P < 0.001); contrast sensitivity was lower in mesopic and glare conditions than under normal lighting condition.

In addition to the drop in contrast sensitivity under unusual lighting conditions (e.g., glare and mesopic), wearing soft contact lenses can further reduce contrast sensitivity in different lighting conditions. Therefore, people who wear contact lenses should be aware of this reduction in visual performance in conditions like driving at night or in the fog.

Creating controllable, reproducible keratectomy wounds in rodent corneas can be a challenge due to their small size, thickness, and the lack of usual tools available for human eyes such as a vacuum trephine. The purpose of this work is to provide a consistent, reproducible corneal stromal defect in rats using a simple, economical, and customized innerstopper guarded trephine.

The inner-stopper guarded trephine is used to induce a circular wound in rat corneas. After trephination, the corneal flap can be removed by manual dissection using a blunt spatula. We used optical coherence topography (OCT) to measure the defect wound depth induced in ex vivo rat eyes.

Despite a minor learning curve, this simple device enables depth control, reduces variability of manual keratectomy wound depth in rats, and decreases the risk for corneal perforation during keratectomy. Corneal defect creation was highly reproducible across different researchers and was independent of their surgical training.

This inner-stopper guarded trephine can be utilized and applied to pre-clinical testing of a wide range of corneal wound healing therapies, including but not limited to biotherapeutics, corneal prosthetics, and regenerative technologies.

The use of amniotic membrane has been suggested in the treatment of infectious keratitis for its intrinsic anti-infective properties probably mediated by its antiinflammatory effects. The aim of this study was to investigate the effect of amniotic membrane transplantation (AMT) along with ciprofloxacin to cure the primary stages of Pseudomonas keratitis.

In total, 28 rabbits were selected and divided in four groups as follows: group 1 as control, group 2 with amniotic membrane, group 3 with ciprofloxacin, and group 4 with amniotic membrane combined with ciprofloxacin. About 0.05 cc suspension of Pseudomonas aeruginosa, 27853 ATCC was injected into corneal stroma.

The results showed groups of AMT, AMT + ciprofloxacin, and ciprofloxacin had 0% perforation while the control group had 85.6%. Average infiltration of 5.5 mm was observed in ciprofloxacin group, 5 mm in AMT + ciprofloxacin group, 24 mm in AMT group, and finally 23.75 mm for control. Amniotic membrane showed to be effective in prevention of cornea perforation as well as remission of Pseudomonas keratitis. There was no significant difference between ciprofloxacin groups in comparison with ciprofloxacin + AMT group. However, regarding the anti-inflammatory effect, the process of improvement of inflammation in ciprofloxacin + AMT group was faster.

Transplantation of amniotic membrane in the primary stages of Pseudomonas keratitis treatment remarkably prevents the disease and it can be used to control its process.

The aim of this case–control study was to determine the impact of environmental factors on the predisposition to develop keratoconus in a sample of Western Algerian population. Subsequently, we were interested in the implication of two single nucleotide polymorphisms (SNPs) IL4 rs2070874 and FOXP3 rs3761548, previously described as contributing to the occurrence of allergy, in the development of keratoconus.

The study included 70 unrelated KC cases and 70 controls originating from Western Algeria. DNA genotyping was done using predesigned probe-based allelic discrimination TaqMan® assays. Allele and genotype frequencies were compared between the cases and controls by Chi-square test and odds ratios with 95% confidence intervals.

A significant association between risk factors such as family history, atopy, eye rubbing, and the development of keratoconus was found in our sample. Smoking would provide a protective effect against the pathology. No statistically significant differences were found in the allele and genotype frequencies between cases and controls neither for IL4 rs2070874 nor for FOXP3 rs3761548.

Our study provides, for the first time, a clear demonstration of the absence of association of the allergy-associated IL4 and FOXP3 polymorphisms with KC in a sample from Western Algerian population.

Viscocanalostomy represents an alternative to standard penetrating glaucoma surgery. The aim of this study is to compare the outcomes of combined phacoemulsification and viscocanalostomy in eyes with primary open-angle glaucoma (POAG) versus eyes with pseudoexfoliation glaucoma (PEXG).

In this prospective non-randomized comparative study, eyes with cataract and POAG or PEXG were enrolled. Pre- and postoperative data including best corrected visual acuity (BCVA), intraocular pressure (IOP), and the number of antiglaucoma medications administered were recorded at each visit. All patients underwent phacoviscocanalostomy. Complete success was defined as the IOP of 21 mmHg or less without the administration of medication while a qualified success reported the same IOP parameters either with or without the administration of medication.

Fifty-four eyes with POAG and fifty-four with PEXG underwent phacoviscocanalostomy. The mean follow-up time was 23.36 ± 8.8 months (range, 6–40 months). The mean postoperative IOP reduced significantly in both groups, although the mean IOP reduction was significantly greater in PEXG eyes (14.7 ± 8.9 vs 10.1 ± 7.7 mmHg) (P = 0.05). At the final follow-up visit, the mean postoperative IOP was 14.1 ± 2.1 and 16.6 ± 3.5 mmHg in the PEXG and POAG eyes, respectively (P = 0.001). A complete success rate of 88.9% and 75.9% was achieved in PEXG and POAG eyes, respectively (P = 0.07). The qualified success rate was 100% in the PEXG and 85.2% in POAG groups (P = 0.03).

Phacoviscocanalostomy achieved significant IOP reduction and visual improvement in both POAG and PEXG patients. Our results indicated that in terms of IOP reduction, this procedure was more effective in treating PEXG.

To estimate carrier frequencies of CYP1B1 mutations p.Gly61Glu and p.Arg368His, respectively, in Talesh and the east of Guilan province in Iran with a maximum error of 2%. Previously, it was shown that these CYP1B1 mutations may be relatively prevalent in these regions.

Population-based screenings were performed. DNA was extracted from saliva samples of 1036 individuals from Talesh and 3029 individuals from the east of Guilan. P.Gly61Glu and p.Arg368His screenings were performed, respectively, by RFLP and ARMS-based PCR protocols. For confirmation, the DNA of individuals with mutations was sequenced using the Sanger protocol.

Nine individuals from Talesh (0.86%; 95%CI: 0.45–1.64%) carried the p.Gly61Glu mutation, and 73 from the east of Guilan (2.41%; 95%CI: 1.91–3.04%) carried p.Arg368His. There was no significant difference in frequencies between urban and rural regions of the various cities, nor among four cities within the east of Guilan.

The frequencies of p.Gly61Glu carriers in Talesh and of p.Arg368His carriers in the east of Guilan were within the 95% confidence interval of a previous study based on screenings of fewer individuals. The reliability of the recent estimates is higher, as the confidence interval for p.Gly61Glu decreased from 6.5% to 1.19% and the interval for p.Arg368His decreased from 4% to 1.13%. Based on the new findings, the maximum expected frequency of p.Gly61Glu carriers in Talesh is 1.64%, and of p.Arg368His carriers in the east of Guilan is 3%. The need for performing premarital screenings in the respective cities can be evaluated

To highlight diagnostic challenges in patients with acquired vitelliform macular degeneration (AVMD) with subretinal fluid (SRF) and to examine the characteristics of image findings in patients with AVMD.

In this retrospective review, the electronic medical record of 22 eyes of 16 patients with AVMD was studied. The rates of SRF, drusen, pigment epithelial detachment (PED), and patient clinical information such as age, length of follow-up, and best-corrected visual acuity (BCVA) were assessed.

The mean age at diagnosis with AVMD was 72 years with a mean follow-up time of 29 months. Median BCVA 20/33 at presentation and 20/33 at final follow-up. Drusen was found in 13 of 22 eyes (59.1%), PEDs in 4 of 22 eyes (18.2%), and SRF in 10 of 22 eyes (45.5%) at some point during their follow-up. Of the 10 eyes with SRF, 70% were center involving, and recurrence occurred in 40%, all in the same location as the initial presentation of SRF. Three eyes received an anti-vascular endothelial growth factor injection for SRF. In 66% of cases receiving an injection, the fluid later relapsed and remitted without further injections during the course of follow-up.

AVMD occurs in the same demographic as age-related macular degeneration (AMD) and has many common features. SRF in AVMD tends to be center involving and recurs usually in the same location as its origin. The use of anti-VEGF injections did not seem to improve SRF in contrast to the SRF seen in wet AMD. Proper differentiation of AVMD may prevent unnecessary long-term treatment with intravitreal anti-VEGF injections.

To quantify the microvasculature density of the optic nerve head (ONH) using optical coherence tomography angiography (OCTA) analysis in patients recovered from Coronavirus Disease 2019 (COVID-19).

In a comparative cross-sectional, observational study, patients recovered from COVID19 whose initial diagnosis was confirmed by a rRT-PCR of a nasopharyngeal sample were included in this study. OCTA of ONH was performed in included patients and normal controls. Vascular density (VD) of the all vessels (AV) and small vessels (SV) inside the disc and radial peripapillary capillary (RPC) network density were measured in COVID-19 recovered patients and compared with similar parameters in an age-matched group of normal controls.

Twenty-five COVID-19 patients and twenty-two age-matched normal controls were enrolled in the study and one eye per participant was evaluated. The mean whole image SV VD in the COVID-19 group (49.31 ± 1.93) was not statistically significantly different from that in the control group (49.94 ±. 2.22; P = 0.308). A decrease in RPC VD was found in all AV and SV VD measured, which became statistically significant in whole peripapillary SV VD, peripapillary inferior nasal SV VD, peripapillary inferior temporal SV VD, peripapillary superior nasal SV VD, and grid-based AV VD inferior sector (P < 0.05). Inside disc SV VD in the COVID-19 group (49.43 ± 4.96) was higher than in the control group (45.46 ± 6.22) which was statistically significant (P = 0.021).

Unremarkable decrease was found in ONH microvasculature in patients who had recovered from COVID-19. These patients may be at risk of ONH vascular complications. Increase in inner disc SV VD may be an indicator of ONH hyperemia and edema.

To study the genetic basis and clinical manifestations of Wolfram syndrome in a multi-affected family.

Complete clinical examinations including urological, ophthalmic, neurological, and endocrinologic assessment were performed for three affected family members. Genomic DNA was extracted from peripheral blood leukocytes with salting out method and all WFS1 exons and their flanking regions were sequenced. Candidate variation was screened for segregation in the pedigree by Sanger sequencing.

A known pathogenic missense mutation in WFS1 gene (c.1885C>T which leads to p.Arg629Trp in the encoded protein) was identified in all affected individuals. Both clinical and genetic investigations confirmed Wolfram syndrome diagnosis with variable phenotypic features.

Identical mutations in the Wolfram syndrome causative gene can lead to variable manifestations of the syndrome even in the same family. Although the medical findings and clinical examination are imperative for the diagnosis of Wolfram syndrome, genetic testing is useful to confirm the diagnosis, especially in cases with possible reduced penetrance of the characteristic signs.

The aim of this study was to determine the efficacy of using 3D printing models in the learning process of orbital anatomy and pathology by ophthalmology residents.

A quasi-experimental study was performed with 24 residents of ophthalmology at Mashhad University of Medical Sciences. Each stratum was randomized into two groups. The educational booklets were distributed, and various forms of orbital 3D models were printed from orbital computed tomography (CT) scans. Knowledge enhancement on the topics was measured by comparing pretest and posttest scores.

Thirteen residents who were trained using traditional methods were deemed the control group; while 11 residents who were trained using the 3D printed models were classed as the intervention group. The control group was younger than the intervention group (P = 0.047). The results showed that there was a statistically significant difference in the total posttest scores between the two groups. Based on the repeated measures of the analysis of variance (ANOVA), score variables were significant between the two groups (P = 0.008). Interestingly, the use of the 3D educational model was more effective and statistically significant with the year one residents as compared to the year two residents (P = 0.002).

This study is the first one in Iran quantifying the effects of learning using 3D printed models in medical education. In fact, 3D modeling training is seemingly effective in teaching ophthalmic residents. As residents have never encountered such technology before, their experience using 3D models proved to be satisfactory and had a surprising positive effect on the learning process through visual training.

To study the effect of near-vision reading task on optical quality of the eye when performed on a computer monitor and on printed paper, and to identify which of the two results in greater changes.

Two groups of subjects performed a 30-min reading task in two different conditions: on a computer monitor and on printed paper. Ocular, corneal, and internal wavefront aberrations (Zernike coefficients up to 6th order), root-mean-square of low- and high-order aberrations, spherical equivalent, vectoral components of ocular astigmatism ( J45 and J0), and the compensation factor between internal and corneal aberrations were measured before and after the tasks. Their changes were analyzed in each group and between groups.

Statistically significant changes in wavefront aberrations and in root mean square of low- and high-order aberrations were observed in both groups which was significantly greater when the task was performed on printed paper. Partial loss of compensation mechanism and variation in spherical equivalent in a negative direction occurred after both reading tasks; however, it was statistically significant only with printed paper reading task. The vectoral components of ocular astigmatism did not show statistically significant changes in either groups.

Near-vision reading tasks can change the optical quality of the eye, especially when the task is performed on printed paper.

To highlight the role of atopobiosis and dysbiosis in the pathomechanism of autoimmune uveitis, therefore supporting fecal microbiota transplant (FMT) and probiotics as potential targeted-treatment for uveitis.

This review synthesized literatures upon the relation between gut microbiota, autoimmune uveitis, FMT, and probiotics, published from January 2001 to March 2021 and indexed in PubMed, Google Scholar, CrossRef.

The basis of the gut–eye axis revolves around occurrences of molecular mimicry, increase in pro-inflammatory cytokines, gut epithelial barrier disruption, and translocation of microbes to distant sites. In patients with autoimmune uveitis, an increase of gut Fusobacterium and Enterobacterium were found. With current knowledge of aforementioned mechanisms, studies modifying the gut microbiome and restoring the physiologic gut barrier has been the main focus for pathomechanism-based therapy. In mice models, FMT and probiotics targeting repopulation of gut microbiota has shown significant improvement in clinical manifestations of uveitis. Consequently, a better understanding in the homeostasis of gut microbiome along with their role in the gut–eye axis is needed to develop practical targeted treatment.

Current preliminary studies are promising in establishing a causative gut–eye axis relationship and the possibility of conducting FMT and probiotics as targeted treatment to mitigate autoimmune uveitis, to shorten disease duration, and to prevent further complications.

Glaucoma is a multifactorial disease and a leading cause of irreversible blindness worldwide. Current data has demonstrated the approximate distribution of primary openangle glaucoma (POAG) in patients of European, African, Hispanic, and Eastern Asian descent. However, a significant gap in the literature exists regarding the prevalence of POAG in Middle Eastern (ME) populations. Current studies estimate ME POAG prevalence based on a European model. Herein we screened 65 total publications on ME prevalence of POAG and specific risk factors using keywords: “glaucoma”, “prevalence”, “incidence”, “risk factor”, “Middle East”, “Mideast”, “Persian”, “Far East”, as well as searching by individual ME countries through PubMed, Embase, Ovid, Scopus, and Trip searches with additional reference list searches from relevant articles published up to and including March 1, 2021. Fifty qualifying records were included after 15 studies identified with low statistical power, confounding co-morbid ophthalmic diseases, and funding bias were excluded. Studies of ME glaucoma risk factors that identify chromosomes, familial trend, age/gender, socioeconomic status, lifestyle, intraocular pressure, vascular influences, optic disc hemorrhage, cup-to-disc ratio, blood pressure, obstructive sleep apnea, and diabetes mellitus were included in this systematic review. We conclude that the prevalence of POAG in the ME is likely higher than the prevalence rate that European models suggest, with ME specific risk factors likely playing a role. However, these findings are severely limited by the paucity of population-level data in the ME. Well-designed, longitudinal population-based studies with rigorous inclusion and exclusion criteria are ultimately needed to accurately assess the epidemiology and specific mechanistic risk factors of glaucoma in ME populations.

Intravitreal methotrexate (MTX) has been proven to be an effective treatment for various intraocular diseases. In this article, a comprehensive review was performed on intravitreal applications of methotrexate. Different aspects of the administration of intravitreal MTX for various clinical conditions such as intraocular tumors, proliferative vitreoretinopathy, diabetic retinopathy, age-related macular degeneration, and uveitis were reviewed and the adverse effects of intravitreal injection of MTX were discussed. The most common indications are intraocular lymphoma and uveitis. Other applications remain challenging and more studies are needed to establish the role of intravitreal MTX in the management of ocular diseases.

Age-related macular degeneration and its complication, subretinal neovascularization, are common causes of progressive, irreversible impairment of central vision. Antivascular endothelial growth factor (anti-VEGF) therapy has improved the visual outcome and provided an evolution in the treatment of retinal disease. The current four antiVEGF drugs – pegaptanib, ranibizumab, aflibercept, and bevacizumab – have been administered for many years. A new anti-VEGF agent, brolucizumab, was approved by the U.S. Food and Drug Administration (FDA) in late 2019 for the treatment of wet agerelated macular degeneration. Brolucizumab is a novel single-chain fragment variable antibody that inhibits all isoforms of VEGF-A and has been suggested to have more tissue penetration. Despite all the benefits, there are some reports of serious side effects that need to be understood in managing patients. Brolucizumab has been reported to cause occlusive retinal vasculitis in the setting of intraocular inflammation, which has not been seen in other anti-VEGF medications. A PubMed and Scopus search was performed and all article types were included. In the present article, we have reviewed the reported side effects of brolucizumab.

Neovascular age-related macular degeneration (AMD) can lead to rapid, irreversible vision loss in untreated eyes. While the pathogenesis of neovascular AMD remains incompletely understood, the choriocapillaris has been hypothesized as the initial site of injury. Due to limitations of dye-based angiography, in vivo imaging of the choriocapillaris has been a longstanding challenge. However, the clinical introduction of optical coherence tomography angiography (OCTA) has enabled researchers and clinicians to noninvasively image the choriocapillaris vasculature, allowing the evaluation of the choriocapillaris in eyes with a variety of pathologies. In this perspective, we review important OCTA-based findings regarding choriocapillaris impairment in neovascular AMD and discuss limitations and future directions of OCTA technologies in the context of this disease.

To report a rare case of isolated intraconal meningioma.

A 24-year-old woman presented with painless proptosis in her left eye which started and progressed during her pregnancy about 10 months ago. Hertel exophthalomometry revealed anterior displacement of the globe with 4 mm of proptosis which was remarkable. Magnetic resonance imaging (MRI) demonstrated an intraconal circumscribed oval-shaped mass with hypointense signals on T1-weighted images and hyperintense signals on T2-weighted images, mimicking cavernous hemangioma. This mass, however, was free of any connections to optic nerve or bones. Due to the imaging characteristics, more prevalent diagnoses like cavernous hemangioma were placed on the top of the differential diagnoses list. However, during the surgical excision, the tumor’s consistency and gross features were not compatible with cavernous hemangioma. The pathologic findings instead determined meningotheliomatous meningioma, a very rare condition, which was far from our expectations prior to the surgery.

Ectopic orbital meningiomas are rare tumors that are not easily diagnosed without postoperative histopathology. Despite its low prevalence, they should be considered in the differential diagnosis list of intraconal masses with hypointense signals on T1-weighted images and hyperintense signals on T2-weighted images.

To report the computed tomography features of a case with complete luxation of the globe after a road traffic accident.

A 35-year-old male presented with pain, loss of vision, and bleeding from the left eye 48 hr after a road traffic accident. The ophthalmic examination of the left upper and lower eyelids showed edema with subcutaneous hematoma, crepitus, and complete blepharoptosis. On retracting the eyelids, the left eyeball was not visible and the patient was not able to perceive light. The left temporal region appeared filled with a soft, palpable globular structure situated beneath the temporalis muscle. A noncontrast computed tomography (NCCT) of the head and orbits showed a comminuted and displaced fracture of the floor, medial, and lateral orbital walls in addition to a displaced tripod fracture of the left zygomatic bone. The intact left eyeball was seen below the temporalis muscle without any optic nerve or extraocular muscle attachment. The virtual reality reconstruction highlighted a contributory supero-temporal defect in the bony orbit, which appeared large enough to accommodate the intact eyeball.

The computed tomography of the orbits provided a detailed location of the luxated eyeball and provided guidance in further management of the case.

We describe a modified allogenic intrastromal lenticule implantation technique for management of keratoconus (KCN). Patients with advanced KCN already scheduled for corneal transplantation were enrolled. An allogenic corneal lenticule was implanted inside a stromal pocket created by femtosecond laser. In three cases, the estimated refractive error of the recipient eyes was corrected on the donor lenticules using an Excimer laser. All operated eyes underwent corneal crosslinking at the time of surgery. This method was named “Femtosecond Laser-assisted Allogenic Stromal Keratoplasty Without and With Excimer Laser-assisted Donor Keratomileusis”; briefly called FASK and FASK Plus EDK, respectively. Two out of five patients were satisfied with the results. There was a decrease in the average simulated keratometric values as well as myopia when FASK Plus EDK was performed. Increased corneal thickness was achieved in all cases. Graft edema gradually decreased over weeks but interface wrinkling and lenticule folds in the visual axis remained as a problem during follow-up period. No other complications were encountered.