Relation of ocular trauma to cortical, nuclear, and posterior subcapsular cataracts: the Beaver Dam Eye Study

The Functional Significance of High Cysteine Content in Eye Lens γ-Crystallins

Cataract disease is strongly associated with progressively accumulating oxidative damage to the extremely long-lived crystallin proteins of the lens. Cysteine oxidation affects crystallin folding, interactions, and light-scattering aggregation especially strongly due to the formation of disulfide bridges. Minimizing crystallin aggregation is crucial for lifelong lens transparency, so one might expect the ubiquitous lens crystallin superfamilies (α and βγ) to contain little cysteine. Yet, the Cys content of γ-crystallins is well above the average for human proteins. We review literature relevant to this longstanding puzzle and take advantage of expanding genomic databases and improved machine learning tools for protein structure prediction to investigate it further. We observe remarkably low Cys conservation in the βγ-crystallin superfamily; however, in γ-crystallin, the spatial positioning of Cys residues is clearly fine-tuned by evolution. We propose that the requirements of long-term lens transparency and high lens optical power impose competing evolutionary pressures on lens βγ-crystallins, leading to distinct adaptations: high Cys content in γ-crystallins but low in βB-crystallins. Aquatic species need more powerful lenses than terrestrial ones, which explains the high methionine content of many fish γ- (and even β-) crystallins. Finally, we discuss synergies between sulfur-containing and aromatic residues in crystallins and suggest future experimental directions.

Correlation between higher-order aberration and photophobia after cataract surgery

Cataract surgery impinges on the spatial properties and wavelength distribution of retinal images, which changes the degree of light-induced visual discomfort/photophobia. However, no study has analyzed the alteration in photophobia before and after cataract surgery or the association between retinal spatial property and photophobia. Here, we measured the higher-order aberrations (HOAs) of the entire eye and the subjective photophobia score. This study investigated 71 eyes in 71 patients who received conventional cataract surgery. Scaling of photophobia was based on the following grading system: when the patient is outdoor on a sunny day, score of 0 and 10 points were assigned to the absence of photophobia and the presence of severe photophobia prevents eye-opening, respectively. We decomposed wavefront errors using Zernike polynomials for a 3-mm pupil diameter and analyzed the association between photophobia scores and HOAs with Spearman’s rank sum correlation (rs). We classified patients into two groups: photophobia (PP) unconcerned included patients who selected 0 both preoperatively or postoperatively and PP concerned included the remaining patients. After cataract surgery, photophobia scores increased, remained unchanged (stable), and decreased in 3, 41, and 27 cases, respectively. In the stable group, 35 of 41 cases belonged to PP unconcerned. In PP concerned, there were significant correlations between photophobia score and postoperative root-mean-square values of total HOAs (rs = 0.52, p = 0.002), total coma (rs = 0.52, p = 0.002), total trefoil (rs = 0.47, p = 0.006), and third-order group (rs = 0.53, p = 0.002). In contrast, there was no significant correlation between photophobia scores and preoperative HOAs. Our results suggest that the spatial properties of retinal image modified by HOAs may affect the degree of photophobia. Scattering light due to cataracts could contribute to photophobia more than HOAs, which may mask the effect of HOAs for photophobia preoperatively.

Optimising the surgical outcome in a case of post-traumatic cataract using ultrasound biomicroscopy

A 12-year-old boy was brought with the chief complaint of diminution of vision in his left eye for the past 1 month. History revealed a blunt trauma to his left eye with a wooden stick 6 weeks ago.Visual acuity was 20/20 and hand movement close to face in right and left eye, respectively, without any relative afferent pupillarydefect. Slit-lamp examination showed a total cataractous lens with signs suggestive of suspected posterior capsular (PC) defect. The PC defect was screened initially using B-scan ultrasound of the posterior segment, followed by confirmation of the same using ultrasound biomicroscopy. Left eye lens aspiration along with limited anterior vitrectomy followed by placement of multipiece intraocular lens in the sulcus was performed. Best-corrected visual acuity at 6 months of follow-up was 20/20.

Prevalence, subtypes, severity and determinants of ocular trauma: The Singapore Chinese Eye Study

PURPOSE

To describe the prevalence, subtypes, severity and determinants of ocular trauma (OT) in a population-based study in Singapore.

METHODS

We included 3353 Chinese adults aged ≥40 years from the Singapore Chinese Eye Study, a population-based study, conducted between 2009 and 2011. OT was defined as self-reported history of any eye injury requiring medical attention with or without hospitalisation, and further classified as blunt object, sharp object or chemical burns related. Age and gender-standardised prevalence was estimated using the 2010 Singapore Chinese population census. Multivariable models were used to assess the independent associations of OT with age, gender, income, education, literacy, alcohol consumption, smoking and history of falls.

RESULTS

The mean (SD) age was 59.7 (9.9) years and 49.4% were male. There were 138 OT cases, giving a crude and age and gender-standardised prevalence of 4.1% (95% CI 3.5% to 4.8%) and 4.4% (95% CI 3.7% to 5.2%), respectively. Of these, 45 (32.6%), 56 (40.6%) and 10 (7.3%) were blunt object, sharp object and chemical burns-related trauma, respectively. Twenty eight (20.3%) required hospitalisation, with no difference between subtypes. In multivariable models, men (OR (95% CI): 2.80 (1.79-4.39)), younger persons (per year decrease in age (1.03 (1.00-1.05)) and lower education levels (1.8 (1.25-2.60); comparing ≤6 years vs >6 years of education) were independent determinants of OT.

CONCLUSIONS

OT affected one in 25 adults, with 20% of these requiring hospitalisation. Because OT is preventable, raising awareness and education strategies in the population would allow prevention of vision loss particularly in men, and younger and lesser-educated individuals.

Care of Older Adults: Role of Primary Care Physicians in the Treatment of Cataracts and Macular Degeneration

This article aims to facilitate optimal management of cataracts and age-related macular degeneration (AMD) by providing information on indications, risk factors, referral guidelines, and treatments and to describe techniques to maximize quality of life (QOL) for people with irreversible vision loss. A review of PubMed and other online databases was performed for peer-reviewed English-language articles from 1980 through August 2012 on visual impairment in elderly adults. Search terms included vision loss, visual impairment, blind, low vision, QOL combined with age-related, elderly, and aging. Articles were selected that discussed vision loss in elderly adults, effects of vision impairment on QOL, and care strategies to manage vision loss in older adults. The ability of primary care physicians (PCPs) to identify early signs of cataracts and AMD in individuals at risk of vision loss is critical to early diagnosis and management of these common age-related eye diseases. PCPs can help preserve vision by issuing aptly timed referrals and encouraging behavioral modifications that reduce risk factors. With knowledge of referral guidelines for soliciting low-vision rehabilitation services, visual aids, and community support resources, PCPs can considerably increase the QOL of individuals with uncorrectable vision loss. By offering appropriately timed referrals, promoting behavioral modifications, and allocating low-vision care resources, PCPs may play a critical role in preserving visual health and enhancing the QOL for the elderly population.

Past History of Ocular Trauma in an Iranian Population-Based Study: Prevalence and its Associated Factors

Purpose:

The purpose of this study was to determine the prevalence of a history of ocular trauma and its association to age, sex, and biometric components.

Materials and Methods:

Residents of Shahroud, Iran aged 40–64 years, were sampled through a cross-sectional study using multistage cluster sampling. Three hundred clusters were randomly selected, and 20 individuals were systematically selected from each cluster. The subjects underwent optometric and ophthalmic examinations, and ocular imaging. A history of ocular trauma was determined through personal interviews.

Results:

The prevalence of a history of trauma and blunt trauma, sharp trauma, and chemical burns were 8.57%, 3.91%, 3.82%, and 1.93%, respectively. After adjusting for age, the rate of all types of trauma was significantly higher for males. Only the prevalence of chemical burns significantly decreased with aging. A history of hospitalization was stated by 1.64% of the subjects. The axial length was significantly longer in cases with a history of trauma. The corneal curvature was significantly larger in cases with a history of sharp trauma and chemical burns. The prevalence of corneal opacities was significantly higher among cases with a history of the blunt trauma odds ratio (OR = 2.33) and sharp trauma (OR = 4.46). Based on corrected visual acuity, the odds of blindness was 3.32 times higher in those with a history of ocular trauma (P < 0.001).

Conclusion:

A considerable proportion of the 40–64-year-old population reported a history of ocular trauma. This observation has important health implications. Blindness, corneal opacities, and posterior subcapsular cataract were observed more frequently among these cases, and they demonstrated differences in some ocular biometric components.

Ophthalmic diseases and disorders in free-ranging rhesus macaque (Macaca mulatta) of Shivalik hill area of Himachal Pradesh, Northern India

BACKGROUND

The studies on ophthalmic diseases and disorders in a population of rhesus macaques, in particular with free-ranging macaques, are limited mainly by the difficulty in capturing animals and obtaining samples.

METHODS

From October 2011 to 2013, prevalence of various ophthalmic affections was recorded and analyzed on the basis of sex, age-group, and disease condition both in urban and peri-urban free-ranging rhesus macaques (Macaca mulatta) from various locations in Shivalik hill areas of Himachal Pradesh in northern India, as a part of clinical health examination.

RESULTS AND CONCLUSION

Ophthalmic diseases were more prevalent in macaques captured from urban settings than those from peri-urban, and difference between two groups was statistically significant (P < 0.01). Further classification of ophthalmic diseases revealed that traumatic injuries, corneal opacity, and cataract were significantly higher in urban than those in peri-urban macaque (P < 0.01). Similarly, the ophthalmic disorders among different age-groups were also found statistically significant (P < 0.01). The effect of sex on ophthalmic disorders was not found significant. Overviewing these results, disturbances in environment, close proximity to humans, and increasing age may lead to ophthalmic occurrences in these free-range macaques.

Risks of cataract in Nigerian metal arc welders

BACKGROUND

Occupational exposure to ultraviolet (UV) radiation from welding is considered a risk factor for cataract and other eye disorders, but the evidence for such effects is limited.

AIMS

To identify any increased risk of developing cataract from metal arc welding and to investigate the associated risk factors.

METHODS

A cross-sectional study was carried out on male welders and control subjects (not engaged in welding) from five fabrication and construction companies in Port Harcourt, Nigeria. A questionnaire was used to gather information regarding their demography and lifestyle, along with their occupational, medical and ocular histories. Cataract was identified by external examination and ophthalmoscopy.

RESULTS

A total of 117 welders and 105 controls participated. There was no statistically significant increase in the risk of cataract in welders after adjusting for age, smoking status, family history of cataract, outdoor work and history of eye injury. There was a strong association between work-related eye-injury history and cataract. Only 60% of welders were wearing eye protection when the eye injury occurred. The majority of the eye injuries (72%) occurred during welding and grinding operations.

CONCLUSIONS

The findings of this study suggest that the main occupational risk factor for cataract was a history of eye injuries. The role of UV (or optical) radiation appeared to be less important than impact eye injuries associated with welding-allied processes. It is therefore important that welders are provided with different types of eye protection and are informed about which type should be used, and when, so that they can be protected against optical and impact injuries.

Prevalence and incidence of ocular trauma in North China: the Beijing Eye Study

PURPOSE

To determine the prevalence and incidence of ocular trauma and proportion of trauma-related visual impairment in the population of Greater Beijing.

METHODS

The population-based Beijing Eye Study included 4439 subjects in 2001, of whom 3251 subjects returned for follow-up examination in 2006 (response rate: 73.3%). The subjects underwent a comprehensive ocular evaluation. Prospective information on ocular trauma and type of treatment was recorded with questionnaires in face-to-face interviews.

RESULTS

A history of ocular trauma was reported by 72 (1.6 ± 0.2%) subjects (age-standardized prevalence: 1.7 ± 0.01%). Prevalence of ocular trauma history was associated with male gender (p = 0.02), rural residence (p = 0.04) and alcohol consumption (p = 0.01). Trauma as underlying cause for visual impairment (best-corrected visual acuity < 20/60 and ≥ 20/400) was found in 4 (6.6%) eyes and as underlying cause for blindness (best-corrected visual acuity <20/400) in three eyes (4.2%). In the survey of 2006, 116 (3.6 ± 0.3%) participants had a self-reported history of ocular trauma, which was associated with male gender (p = 0.002), low income (p = 0.01) and alcohol consumption (p = 0.016). The 5-year incidence of ocular trauma was 2.6 ± 0.3%, which was associated with male gender (p = 0.02), younger age (p = 0.037) and lower income (p = 0.009).

CONCLUSIONS

In the adult population of Greater Beijing with an age of 40+ years, the prevalence of ocular trauma was 1.6 ± 0.2% and was associated with male gender, rural residence and alcohol consumption. The age-standardized ocular trauma prevalence of 1.7 ± 0.01% was comparable with figures from Caucasian populations. The 5-year incidence of ocular trauma of 2.6 ± 0.3% was associated with male gender, younger age and lower income.

A novel splicing mutation of the FRMD7 gene in a Chinese family with X-linked congenital nystagmus

PURPOSE

To identify a potential pathogenic mutation in a four-generation Chinese family with X-linked congenital nystagmus (XLCN).

METHODS

Routine clinical examination and ophthalmic evaluation were performed on normal controls, two patients and two healthy members of the family. Genomic DNA was prepared from the peripheral blood of members of the family and from 50 normal controls. All coding exons and the intronic boundaries of the four-point-one (4.1), ezrin, radixin, moesin (FERM) domain-containing 7 (FRMD7) gene were amplified using polymerase chain reaction (PCR) followed by direct sequencing.

RESULTS

A previously unreported splicing mutation, c.163-1 G→T transversion (c.163-1 G>T), was detected preceding exon3 of FRMD7 in the patients but not in the unaffected family members and 50 unrelated healthy individuals.

CONCLUSIONS

We identified a novel mutation (c.163-1 G→T) of FRMD7 in this Chinese family with XLCN. Our finding is the first report related to c.163-1 G→T mutation in FRMD7. The result expands the mutation spectrum of FRMD7 in association with congenital nystagmus.

The prevalence and risk factors of ocular trauma: the Singapore Indian eye study

PURPOSE

To describe the prevalence and risk factors of ocular trauma in an urban Southeast Asian population.

METHODS

A population-based survey of 3,400 (75.6% response rate) adults of Indian ethnicity aged 40-80 years residing in Singapore was conducted in 2007-2009. An age-stratified (10-year age group) random sampling procedure was performed to select participants. Ocular trauma was defined as any eye injury requiring medical attention and any history of ocular trauma was documented using a standardized and validated questionnaire comprising seven questions. Potential risk factors associated with ocular trauma included age, gender, socioeconomic status, occupation, housing type, alcohol consumption, smoking, diabetes mellitus, hypertension and history of falls.

RESULTS

Ocular trauma was reported in 5.1% (n = 162; 95% confidence interval [CI] 4.3-6.1%) of the study population, of whom 26.5% (n = 43) required hospitalization. A total of 42.0% (n = 68) of cases resulted from a blunt object, 36.4% (n = 59) from a sharp object, and 15.4% (n = 25) from chemical burns. After adjusting for age and sex, men had a higher prevalence of ocular trauma (7.1% vs. 3.0%, age-adjusted odds ratio [OR] 2.2, 95% CI 1.6-3.1). A history of cigarette smoking was associated with higher likelihood of ocular trauma (OR 1.6, 95% CI 1.1-2.4) but not consumption of alcohol (OR 1.0, 95% CI 0.6-1.6).

CONCLUSIONS

One in twenty Indian adults in this urban Southeast Asian population had a history of ocular trauma, similar to the prevalence reported in Malays living in Singapore. Men and cigarette smokers were more likely to have incurred ocular trauma.

Management of crystalline lens dislocation into the anterior chamber in a victim of domestic violence

A 53-year-old woman presented with a right eye injury due to domestic violence. The crystalline lens in that eye was completely dislocated into the anterior chamber, fixated by the cornea and the iris. Fundoscopy showed a mild vitreous haemorrhage and a giant retinal tear. A modified lensectomy with a fragmatome was performed. During this procedure the capsule was preserved first to minimise the risk of corneal damage and second to reduce vitreous traction, which would repair the giant retinal tear.

Bilateral cataract in a cynomolgus monkey

Severe bilateral cataract was found in a 7 year-old naïve female cynomolgus monkey (Macaca fascicularis) 3 months before necropsy. During macroscopic examination, severe opacity and thinning of the lens were observed in both eyes. Histopathology revealed that the lens nuclei and majority of cortex lens fibers had disappeared and become excavated, while the lens fibers in the subcapsular area were swollen and distorted. Other observations included atrophy and vacuolation in the lens epithelial cells and proliferation of spindle cells and collagen fiber beneath the anterior capsule of the right eye. Immunohistochemical staining of these spindle cells revealed the presence of vimentin, cytokeratin and α-smooth muscle actin (α-SMA), which were considered to be derived from lens epithelial cells. This is a rare case of spontaneous, bilateral, hypermature cataract in a cynomolgus monkey.

Cystatin C, other markers of kidney disease, and incidence of age-related cataract

OBJECTIVE

To investigate the 15-year incidence of 3 specific types of age-related cataract as related to cystatin C and other measures of kidney function.

METHODS

Examinations of a population-based cohort (n = 4926) occurred at 5-year intervals for 15 years. Assessment of medical history, examination, and photographs of the lens after pupil dilation were performed at each examination. Protocols for photography and grading were used. Laboratory measures were from specimens collected at baseline.

RESULTS

In multivariable analyses, a 1-SD increase in the logarithm of cystatin C was associated with 15-year incidence of cortical (odds ratio [OR], 1.24; 95% confidence interval [CI], 1.09-1.41) and posterior subcapsular (OR, 1.24; 95% CI, 1.02-1.50) cataracts. One SD increase in the logarithm of blood urea nitrogen and creatinine were associated with 15-year incidence of posterior subcapsular cataract (OR, 1.22; 95% CI, 1.04-1.42 and OR, 1.26; 95% CI, 1.03-1.54, respectively).

CONCLUSION

Increased levels of cystatin C are associated with increased risk of specific types of age-related cataract. Whether the associations are due to the metabolic changes associated with decreased renal function, common genes, or both awaits further research.

Does Blunt Ocular Trauma Induce Corneal Astigmatism?

PURPOSE

To determine the effect of blunt ocular trauma on refractive astigmatism.

METHODS

Eighty-six eyes of 86 patients with known previous refractive status exposed to blunt ocular trauma were included in the study. Trauma-induced astigmatism (TIA) was calculated using vector analysis. In eyes with TIA, central corneal thickness was assessed by ultrasound pachymetry, and corneal topographies were obtained. Anterior-chamber angles were examined by Goldmann 3-mirror lens to find microhemorrhages, scarring, or recession. Patients were followed up between 8 and 12 months (average, 9.2 months).

RESULTS

In 18 eyes (21%), TIA was detected. Six (7%) of these eyes had lenticular astigmatism caused by traumatic lens subluxation. In the remaining 12 eyes (14%), corneal topography showed regular astigmatic patterns, which were symmetrical in 3 eyes and asymmetric in the remaining 9. The etiologic factor was a game marble in 6 eyes and a stone in the remaining 6. The mean central corneal thickness was 535.75 microm (range, 498-570 microm) in these 12 eyes. In 9 of these 12 eyes, recession or scarring in the anterior-chamber angle was detected at 1 edge of the steepest axis.

CONCLUSIONS

Blunt trauma can induce astigmatism. Hard and small objects are more likely to induce astigmatism.

Markers of inflammation, vascular endothelial dysfunction, and age-related cataract

PURPOSE

To examine the associations of systemic markers of inflammatory disease and vascular endothelial dysfunction with three types of age-related cataract.

DESIGN

Cross-sectional analyses of data from a population-based sample of adults.

METHODS

Standardized protocols for blood collection, measurement of markers, administration of a questionnaire, and grading of lens photographs to determine cataract were used. Univariable and multivariable analyses were performed.

SETTINGS

Cohort in Beaver Dam, Wisconsin.

STUDY POPULATION

A random sample of 396 persons who were > or =50 years of age.

MAIN OUTCOME MEASURE

Prevalent age-related nuclear, cortical, and posterior subcapsular cataract.

RESULTS

Interleukin-6 and intracellular adhesion molecule-1 were associated significantly with prevalent nuclear cataract (odds ratio for each quartile, 1.45 and 2.17, respectively). Many of the associations of markers with cataract types were not linear. There were no significant associations between the markers and cortical or posterior subcapsular cataract.

CONCLUSION

Two serum markers of systemic inflammation and vascular endothelial dysfunction were associated with nuclear cataract.