Prevalence of pterygium and its associated factors among adults aged 18 years and above in Gambella town, Southwest Ethiopia, May 2019

Prevalence and associated factors of corneal opacity among adults in Kolladiba town, Northwest Ethiopia: a cross-sectional study

OBJECTIVE

This study aimed to assess the prevalence and associated factors of corneal opacity among adults in Kolladiba town, Northwest Ethiopia.

METHODS AND ANALYSIS

A community-based cross-sectional study was conducted using a systematic random sampling technique. A total of 846 adult individuals were recruited for the study. Ethical approval was obtained from the University of Gondar School of Medicine Ethical Review Committee. A standardised, semistructured questionnaire plus an ocular examination were used to collect the data. The data were entered into Epi Info V.7 and cleaned and analysed using SPSS V.26. Binary and multivariable logistic regression analyses were performed to select candidate variables and identify statistically significant factors. Variables with a p value of less than 0.05 according to the multivariable logistic regression analysis were considered to be statistically significant.

RESULTS AND CONCLUSION

The prevalence of corneal opacity among the study participants was 27.2% (95% CI 24.4% to 30.4%). In this study, age 49-60 years (adjusted OR (AOR): 1.90; 95% CI 1.03 to 3.32), age ≥61 years (AOR=2.12; 95% CI 1.17 to 3.87), inability to read and write (AOR=2.65; 95% CI 1.68 to 4.16), middle-income level (AOR=2.12; 95% CI 1.30 to 3.47) and poor income level (AOR=4.96; 95% CI 3.04 to 8.09) were factors that were significantly associated with corneal opacity.In this study, the prevalence of corneal opacity was considerably high. Being poor and unable to read and write were the primary factors significantly associated with corneal opacity. Hence, concerned stakeholders should strive to reverse the effects of corneal opacity on the quality of life of the study and causal studies should be considered in the future.

Genetic evidence implicating circulating lipids and lipid drug targets in pterygium

There is limited knowledge about the impact of circulating lipids and lipid-modifying drugs on pterygium development, with conflicting results reported. Our study aimed to address these questions by applying the Mendelian randomization (MR) approach. A two-step MR model was developed. In the first step, bidirectional two-sample MR was employed to establish the causal relationship between circulating lipids and pterygium risk. In the second step, drug-target MR analysis was conducted to assess the causal effect of proprotein convertase subtilisin/kexin type 9 (PCSK9) and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) inhibitors on pterygium outcomes. Genetically predicted low-density lipoprotein cholesterol (LDL-c) levels were found to be significantly associated with an increased risk of pterygium (Inverse variance weighted [IVW] odds ratio [OR] = 2.227; P = 1.53 × 10-4). Similarly, higher total cholesterol (TC) levels exhibited a suggestive association with greater susceptibility to pterygium (IVW OR = 1.806; P = 1.70 × 10-3). Through drug-target MR, a positive causal association was noted between HMGCR-mediated LDL-c levels and pterygium (IVW OR = 6.999; P = 0.016), suggesting that statins may be effective in reducing pterygium risk. The present findings suggest that circulating TC and LDL-c are risk factors for pterygium. Additionally, the results indicate that HMGCR inhibitors, which lower LDL-c levels, have a potential protective effect on pterygium outcomes. Further research is warranted to elucidate the underlying mechanisms involved in pterygium pathogenesis, with a particular focus on cholesterol metabolism.

Current social determinants of health and social risk factors in conditions of the cornea: a scoping review

PURPOSE OF REVIEW

To achieve health equity in eye health and vision care, social determinants of health (SDoH) and the associated social risk factors must be addressed. To address SDoH and social risk factors in ophthalmology, they must first be identified. The purpose of this review was to determine the SDoH and social risk factors in conditions of the cornea that have most recently been explored.

RECENT FINDINGS

This review identified social risk factors associated with all five domains of SDoH, as outlined by Healthy People 2030. The neighborhood and built environment was the domain identified the most for both exploration and observation. The social and community context domain was the least explored, and healthcare access and quality and social and community context domains were the least observed. The cornea condition explored the most in relation to SDoH was dry eye syndrome.

SUMMARY

The findings from this review can inform clinicians on the social risk factors that could be screened for in eye care facilities, so patients can be connected with services to minimize the impact of social risk factors on cornea conditions. Furthermore, the findings have identified cornea conditions and domains of SDoH that are understudied which can be an area for future studies by vision researchers.

Amniotic membrane transplantation and conjunctival autograft combined with mitomycin C for the management of primary pterygium: A systematic review and meta-analysis

Background

Pterygium is a common ocular surface disease. Recurrence is the greatest concern in the treatment of pterygium. Thus, a standardized and effective treatment modality with minimal risk for complications is needed for the management of pterygium. The aim of this systematic review and meta-analysis was to evaluate different tissue grafting options, including conjunctival autograft (CAG) with mitomycin C (MMC), CAG alone, and amniotic membrane transplantation (AMT), for the management of primary pterygium.

Methods

We searched the MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases for relevant studies. We included randomized controlled trials (RCTs) in which CAG + MMC and AMT were compared with surgical excision with CAG alone for the treatment of primary pterygium. The rates of recurrence and adverse events reported in the studies were also evaluated. Risk ratio (RR) was used to represent dichotomous outcomes. The data were pooled using the inverse variance weighting method. The quality of the evidence derived from the analysis was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Risk of bias was assessed using the revised Cochrane risk-of-bias tool for randomized trials.

Results

Twelve RCTs (n = 1144) were deemed eligible and included for analysis. Five RCTs had a low risk of bias, five had some concerns, and two had a high risk of bias. Subgroup analysis showed a statistically significant reduction in the rate of pterygium recurrence after CAG + MMC (RR = 0.12; 95% confidence interval [CI], 0.02–0.63). This outcome was rated as high-quality evidence according to the GRADE criteria. There were insignificant differences between the rates of recurrence after AMT and CAG (RR = 1.51; 95% CI, 0.63–3.65). However, this result was rated as low-quality evidence. Regarding adverse events, patients treated using AMT showed significantly lower rates of adverse events than those treated using CAG (RR = 0.46; 95% CI, 0.22–0.95). However, this finding was rated as low-quality evidence as well. CAG + MMC showed a safety profile comparable to that of surgical excision with CAG alone (RR = 1.81; 95% CI, 0.40–8.31). This result was also rated as low-quality evidence.

Conclusion

A single intraoperative topical application of 0.02% MMC during excision of pterygium followed by CAG has significantly shown to decrease the rate of pterygium recurrence to 1.4% with no severe complications.

A case of spontaneous avulsion of primary pterygium analyzed with anterior segment optical coherence tomography

Purpose

This study reports a case of the spontaneous avulsion of primary pterygium with anterior segment optical coherence tomography (AS-OCT) findings.

Observation

A 72-year-old woman complained of acute pain of the left eye. Primary pterygia were noted in both eyes on the initial examination 4 months ago. Slit-lamp microscopy revealed a nasal corneal epithelial defect, and the rolled elevated lesion in the corneal limbus of the left eye. She was diagnosed with a spontaneous avulsion of the corneal pterygium head. Then the avulsed pterygium head slowly recurred. The pterygium head of the fellow eye had a yellow-whitish elevated lesion beneath the epithelium with poor vascularity. AS-OCT revealed hyper-reflective foci beneath the epithelium corresponding to the yellow-whitish elevated lesion.

Conclusions/importance

The present case revealed the spontaneous avulsion of the pterygium head leading to the corneal epithelial defects and ocular pain, while the pterygium head of the fellow eye showed subepithelial hyper-reflective foci suspicious of spheroidal degeneration on AS-OCT. In this case, the cause of spontaneous avulsion of the pterygium head might be potentially weak adhesion to the cornea due to spheroidal degeneration.

Precis

This case is a primary pterygium leading to spontaneous avulsion, in which hyper-reflective foci were noted in OCT.

Computer-Assisted Pterygium Screening System: A Review

Pterygium is an eye condition that causes the fibrovascular tissues to grow towards the corneal region. At the early stage, it is not a harmful condition, except for slight discomfort for the patients. However, it will start to affect the eyesight of the patient once the tissues encroach towards the corneal region, with a more serious impact if it has grown into the pupil region. Therefore, this condition needs to be identified as early as possible to halt its growth, with the use of simple eye drops and sunglasses. One of the associated risk factors for this condition is a low educational level, which explains the reason that the majority of the patients are not aware of this condition. Hence, it is important to develop an automated pterygium screening system based on simple imaging modalities such as a mobile phone camera so that it can be assessed by many people. During the early stage of automated pterygium screening system development, conventional machine learning techniques such as support vector machines and artificial neural networks are the de facto algorithms to detect the presence of pterygium tissues. However, with the arrival of the deep learning era, coupled with the availability of large training data, deep learning networks have replaced the conventional networks in screening for the pterygium condition. The deep learning networks have been successfully implemented for three major purposes, which are to classify an image regarding whether there is the presence of pterygium tissues or not, to localize the lesion tissues through object detection methodology, and to semantically segment the lesion tissues at the pixel level. This review paper summarizes the type, severity, risk factors, and existing state-of-the-art technology in automated pterygium screening systems. A few available datasets are also discussed in this paper for both classification and segmentation tasks. In conclusion, a computer-assisted pterygium screening system will benefit many people all over the world, especially in alerting them to the possibility of having this condition so that preventive actions can be advised at an early stage.