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1.
The possibility of a relation between high myopia and lens opacity was studied. For this research, the Lens Opacity Meter 701 was used. The lens opacity values measured in 91 high-myopic eyes were compared with those measured in a control group of 106 emmetropic eyes. This comparison showed that myopic had always higher lens opacity values than emmetropic ones, and this result was statistically significant after the age of 20.  相似文献   

2.
The sensitivity of the visual field declines with age. The density of the crystalline lens increases with age and may be partly responsible for the decline in sensitivity. To determine whether lens opacity influences the mean threshold of the visual field, 82 normal subjects were enrolled. All had their lens opacity measured with the Interzeag Lens Opacity Meter 701 and the visual field assessed with the Ring Resolution Perimeter. Lens opacity was highly correlated with age, while mean visual field threshold was also correlated with age but showed much greater variation. Multiple regression failed to show any influence of lens opacity measurements on the mean field threshold after age had been accounted for.  相似文献   

3.

Purpose

To investigate the long-term characteristics of cataracts among adults aged 30 to 49 years in Korean over a span of 10 years.

Methods

Subjects between the ages of 30 to 49 years who underwent cataract surgery at St. Mary''s Hospital from 1995 to 2004 (n = 976) were included. Patients with a history of ocular trauma, uveitis, other ocular or systemic diseases, and congenital cataracts were excluded. Additional information including type of lens opacity, urban/rural region, and pre- and postoperative visual acuities were analyzed. Lens opacity grading was conducted using Lens Opacity Classification System III. The Cochran-Armitage proportion trend test was used to analyze vision changes with the passage of time.

Results

Among the patients who had undergone cataract surgeries, 8.8% (976 / 11,111) met the inclusion criteria. The mean age was 41.7 ± 5.45 years. Gender breakdown of the patient population included 79.0% male and 21.0% female. In terms of home environment, 60.9% were from an urban region and 39.1% from a rural region. Opacity type included anterior polar (AP), posterior subcapsular (PSC), AP and PSC, cortical, and nuclear in 35.7%, 35.1%, 7.0%, 6.0%, and 5.4% of patients, respectively. At a 2-month postoperative follow-up appointment, 92.7% of patients showed a best-corrected visual acuity of more than 20 / 40.

Conclusions

Predominance of AP and PSC opacities as well as male patients was observed in this study population.  相似文献   

4.
PURPOSE: To compare lens thickness (LT), lens position (LP), relative lens position (RLP), and degree and type of lens opacity between affected and fellow eyes of subjects with acute primary angle closure (APAC) to identify any differences in lens characteristics that may be contributory to the acute episode. In addition, axial length (AL) and anterior chamber depth (ACD) measurements were evaluated. METHODS: Seventy-three study subjects with unilateral APAC were treated with sequential laser iridotomy (LI) in both eyes. Two weeks after LI, ACD, LT, and AL measurements were made in both eyes using ultrasound pachymetry. LP was defined as ACD+1/2LT and RLP as LP/AL. The Lens Opacity Classification III (LOCS III) System was used for grading lens opacity. RESULTS: The subjects were 90% Chinese and 63% female. Mean age was 61.0+/-10.9 years. Significant differences between the affected and fellow eyes were found in the ACD (2.11+/-0.35 vs 2.18+/-0.23; P=0.02) and LP (4.61+/-0.47 vs 4.75+/-0.29; P=0.02). Cortical opacity was greater in fellow eyes (0.32+/-0.72 vs 0.53+/-0.95; P=0.02). There was no difference in LT, RLP, or degree of lens opacity in the nuclear and posterior subcapsular regions. CONCLUSIONS: Compared with fellow eyes, APAC-affected eyes have shallower ACD, more anterior LP, and less cortical opacity. These differences may be contributory to APAC.  相似文献   

5.
Purpose: To determine the influence of lens opacities on temporal contrast sensitivity, measured by the full-field flicker test (”Erlangen flicker test”). Methods: Thirty-six consecutive patients (mean age 71.1±11.6 years, 12 male, 24 female, refractive error –1.5±3.8 dpt) with cataract (visual acuity 0.21±0.16, retinal acuity 0.56±0.32, no glaucoma) were studied. Temporal contrast sensitivity (full-field flicker test, 37.1 Hz) and lens opacity (back scatter Lens Opacity Meter, Interzeag) were measured preoperatively and on the 3rd postoperative day. Statistics: nonparametric tests (Wilcoxon-test, Spearman correlation coefficient, Mann-Whitney U-test). Results: No significant difference was seen in temporal contrast sensitivity pre- and postoperatively, but there was a significant difference in lens opacity measurements pre- and postoperatively. No significant correlation was found between temporal contrast sensitivity and lens opacity values preoperatively and postoperatively. Conclusion: The temporal contrast sensitivity, measured by the full-field flicker test, seems to be independent of lens opacity due to the range of cataract included in this study. The data indicate that the full-field flicker test is useful for early glaucoma detection even in patients with cataract formations. Received: 4 October 1999 Revised: 14 December 1999 Accepted: 10 January 2000  相似文献   

6.
Purpose: To evaluate the prevalence and risk factors of lens opacities in a geographically defined population of subjects with type 2 diabetes mellitus compared with a control population. Methods: Subjects in the community of Laxå with a diagnosis of type 2 diabetes mellitus (n = 275) and a control group (n = 256) participated in the study. Lens opacities were graded with Lens Opacities Classification System II in all participants. Lens Opacities Classification System score ≥2 was considered as significant lens opacity. Anthropometric and blood chemistry data were collected for all participants in connection with the eye examination. For the diabetic population, yearly updated information on glucose control, blood pressure and body mass index was available through medical records from diabetes diagnosis until the time of the eye examination. Results: The prevalence of significant cortical, posterior subcapsular and nuclear cataract was 65.5%, 42.5% and 48.0%, respectively, in the type 2 diabetes population in Laxå. In logistic regression analyses, all types of lens opacities were strongly associated with age (p < 0.0001). Cortical lens opacity was also associated with a diagnosis of diabetes (p < 0.0001), posterior subcapsular lens opacity with HbA1c (p < 0.0001) and nuclear lens opacity with female gender and higher heart rate (both p = 0.0004). In the diabetic population, all types of cataract were likewise strongly associated with age (p < 0.0001), posterior subcapsular cataract with HbA1c (p = 0.0032), nuclear cataract with female gender (p = 0.0002) and higher heart rate (p = 0.0008). Conclusions: Our study shows that cortical cataract is associated with diabetes mellitus, not necessarily defined by glucose control, whereas posterior subcapsular cataract is associated with glucose levels. Nuclear cataract is not associated with diabetes mellitus, but is more frequent in women and is also associated with higher heart rate.  相似文献   

7.
The Opacity Lensmeter is a new instrument permitting the measurement of lens opacity. This preliminary report was performed on 98 patients (195 phakic eyes). Age, sex, lens opacity and retinal sensibility (using automated perimetry with the Octopus 2000 R) were assessed. A correlation between age and lens opacity was found in a simple linear regression model on 186 eyes (available data): opacity = 0.00423 square (age) + 5.18. An another more precise correlation was found in 138 eyes, excluding those with anterior segment abnormalities and corneal opacity: opacity = 0.0035 square (age) + 5.17. No statistical differences were observed between lens opacity and sex nor were left/right differences significant. No conclusion was possible concerning retinal sensibility and measured lens opacity because of the small sample (25 eyes). This easily handled instrument may be helpful in daily practice to evaluate opacity in lens pathology. Furthermore, it should be useful for the interpretation of the respective role of cataract and retinal damage in P.O.A.G. loss of retinal sensibility.  相似文献   

8.
The quantitative influence of cataracts on visual fields was studied in 11 patients before and after cataract extraction with intraocular lens implantation. Lens opacity, measured with the Opacity Lens Meter 701, correlated closely with the visual field changes. Measurement of stray light backscattered from the cataractous lens permits quantitative prediction of the influence of cataract on the visual field.  相似文献   

9.
AIM: To study whether specific anesthetic drugs or tear layer evaporation was primarily responsible for the acute cataract and what the change of lens structure is in anesthetized mice. METHODS: Five groups were set up in the experiment: Group A (topicamide and phenylephrine mixed eye drop+ chloral hydrate), Group B (tropicamide and phenylephrine mixed eye drop+sevoflurane), Group C (tropicamide and phenylephrine mixed eye drop), Group D (topicamide and phenylephrine mixed eye drop+chloral hydrate, carbomer eye drop in the right eyes), and Group E (tropicamide and phenylephrine mixed eye drop+sevoflurane, carbomer eye drop in the right eyes). A simple classification system was used to assess the severity of lens opacity. And a numerical value from 0 to 3 to each grade was assigned for the cataract index calculation and data analysis. The gross appearance and time course of development of lens opacity were assessed. Hematoxylin and eosin staining was used to observe the lens structure changes in the reversible cataract. RESULTS: Tropicamide did not induce lens opacification in mice. Lens opacity caused by inhaled sevoflurane was similar to injected cholral hydrate. Both inhaled-anesthetic-induced lens opacity and injected-anesthetic-induced lens opacity could be prevented by carbomer eye drop. In the severe opacity lens, a wide range of lens fiber cell structure had disordered. The fiber cells became uneven thickness. CONCLUSION: The acute reversible lens opacity can unilaterally develop or be induced by a local cause. The structure of lens fiber cells changed in the lens opacity which may influence the permanent connection of the lens fiber cells. This study was not only of practical significance to help maintain lens transparency for eye research, but also of the deeper consideration about the reversible lens opacification phenomenon.  相似文献   

10.
PURPOSE: To compare values of the human lens autofluorescence and back light scatter measurements with the improved Lens Opacities Classification System, LOCS III. METHODS: We measured autofluorescence and back light scatter of the lens from 122 smoking males aged 57 to 76 years who participated in a cancer prevention study. The retroillumination and slit-lamp photographs of the lenses were graded according to LOCS III by the Center for Ophthalmic Research in Boston. Lens fluorometry was carried out with a previously described technique using blue-green (495 nm/520 nm) autofluorescence range. Interzeag Lens Opacity Meter 701 was used for light scatter measurements. RESULTS: LOCS III nuclear opalescence and color grades were statistically significantly correlated with lens autofluorescence as well as with light scatter values. The lens transmission index of autofluorescence measurements showed the highest correlation with the nuclear color (r = -0.71; p < 0.0001) and the light scatter value with nuclear opalescence (r = 0.64; p < 0.0001). There was no correlation between autofluorescence measurements and LOCS III grades of cortical or posterior subcapsular cataract. A weak relation could be found between the grades of cortical cataract and light scatter values. CONCLUSIONS: The lens fluorometry provides a practical clinical technique to evaluate the yellow coloration and opalescence of the human lens nucleus. It may be a useful additional tool together with a subjective grading system in the follow-up of optical changes occurring in the nuclear region of the lens.  相似文献   

11.
PURPOSE: To ascertain whether the exfoliation syndrome (EXS) is a risk factor for cataract development. SETTING: Helsinki University Eye Hospital, Helsinki, Finland. METHODS: This prospective study examined the development of lens opacities using the Lens Opacity Meter. Visual acuity and refraction were measured in both eyes of 63 nonglaucomatous patients with clinically unilateral EXS. After 5 years, 46 patients were available for follow-up. Case histories of 14 patients were recorded. RESULTS: During the 5 year study, the rate of conversion to bilateral disease was 22% and to exfoliative glaucoma, 30%. At the beginning of the study, the mean lens opacity was 23.5 opacity units (OU) +/- 6.7 (SD) in EXS eyes and 22.9 +/- 7.2 OU in fellow, initially nonexfoliative (NE) eyes; the difference was not significant. After 5 years, the mean opacity was 30.0 +/- 8.8 OU in EXS eyes and 26.9 +/- 8.3 OU in NE eyes (P <.001). In patients who remained unilaterally affected, the EXS eye had a higher opacity value than the NE eyes at the start of the study (23.6 +/- 7.3 OU and 22.7 +/- 7.2 OU, respectively) (P <.05) and after 5 years (29.9 +/- 9.0 OU and 27.0 +/- 8.5 OU) (P <.01). There was a significant myopic change in refraction over time in both groups. The mean refraction in EXS eyes was +1.02 +/- 2.48 diopters (D) at the start and + 0.11 +/- 3.06 D after 5 years (P =.0001) and in NE eyes, +0.99 +/- 2.25 D and +0.43 +/- 2.55 D, respectively (P <.01). At the start of the study, the mean difference in refraction between fellow eyes (refraction in NE eye - refraction in EXS eye) was -0.27 +/- 1.00 D. After 5 years, it was +0.32 +/- 1.44 D (P =.016), showing a greater myopic change in EXS eyes. CONCLUSION: The results show that EXS is a risk factor for lens opacification.  相似文献   

12.
PURPOSE: To obtain estimates of the prevalence of lens opacities in an Indian setting by using photographically acquired lens images. METHODS: In 11 randomly sampled villages from a rural district of Haryana, North India, 1443 people (median age 60 years), 52% women, were identified from enumeration of the > or =50-year age group; 87% attended an eye examination. Digital images of cortical and posterior subcapsular opacities and photographs of nuclear opacities were graded using the Lens Opacity Classification System (LOCS) II. The prevalence of opacities was based on a grade of 2 or higher in the worse eye for nuclear, cortical, or posterior subcapsular opacities. RESULTS: Of the participants, 1071 people had gradable images; a further 163 had undergone surgery or had dense opacities. Nuclear opacities were the most common type, with an overall prevalence of 56.9% (95% CI, 53.0-60.6). Posterior subcapsular opacities occurred in 20.6% (95% CI, 17.9-25.8) and cortical opacities in 21.6% (95% CI, 17.9-25.8). Prevalence rose steeply with age for all opacities and was higher in the women than in the men for cortical opacities (P = 0.03). The prevalence of any type of lens opacity including surgical cases and dense opacities was 75.3% (95% CI, 71.4-78.81). CONCLUSIONS: These results highlight the substantial excess of lens opacities in India compared with Western populations.  相似文献   

13.
Seah SK  Wong TY  Foster PJ  Ng TP  Johnson GJ 《Ophthalmology》2002,109(11):2058-2064
OBJECTIVE: To determine the prevalence of lens opacity among Chinese residents of Singapore. DESIGN: Population-based, cross-sectional survey. PARTICIPANTS: Chinese men and women aged 40 years or more in Singapore. METHODS: A stratified, clustered, random sampling method, with more weights given to the older age groups, was used to initially select 2000 Chinese persons aged 40 to 79 years from the 1996 electoral register in the Tanjong Pagar district in Singapore. Eligible subjects (n = 1717) were invited for a comprehensive ocular examination at a centralized clinic, after which nonrespondents were examined in their homes with portable instruments. MAIN OUTCOME MEASURES: Lens opacity, as determined clinically at the slit lamp using a modification of the Lens Opacity Classification System III. Prevalence rates were age adjusted to the 1997 Singapore census population. RESULTS: Of the 1232 persons examined (71.8%), 1206 (70.2%) provided lens data for this analysis. The age-adjusted prevalence of any cataract surgery was 5.1% (95% confidence interval [CI], 3.6, 6.5), with similar rates between men and women. The age-adjusted prevalence of specific types of lens opacity was 22.6% (95% CI, 19.8, 25.4) for any nuclear opacity, 23.9% (95% CI, 21.0, 26.8) for any cortical opacity, and 7.0% (95% CI, 5.3, 8.8) for any posterior subcapsular opacity. The overall age-adjusted prevalence of any cataract or cataract surgery was 34.7% (95% CI, 31.5, 38.0), increasing from 7.0% in those 40 to 49 years and to 94.3% in those 70 years and older (P < 0.001, test for trend for age). When the prevalence of distinct types of lens opacity in an eye was considered, the most common was mixed (age-adjusted prevalence, 11.5%, based on right eye data), followed by nuclear only (9.7%), cortical only (8.3%), and posterior subcapsular only (0.6%). For all cataract types, the prevalence was similar in men and women and was higher in persons examined at their homes than in those examined at the study clinic. CONCLUSIONS: These population-based data suggest that cataract is common among adult Chinese residents in Singapore, despite ready access to cataract surgical services. Persons accepting the offer of free eye examinations were less likely to have cataract than those who did not take up this offer.  相似文献   

14.
外伤性白内障人工晶体植入时机与后囊混浊发生的关系   总被引:10,自引:2,他引:10  
对50例外伤性白内障人工晶体植入术随访观察,平均随访20.7月(8~46月),分组比较术后后囊混浊发生情况:儿童组与成人组发生率分别为77.78%和15.63%,二者有极显著差异。伤后4~14天手术组发生率低于其他时间组,与伤后15天~3月手术组比较有显著差异。结果表明:后囊混浊的发生与病人年龄和手术时期有关。简述了后囊混浊的病因和发病机制。  相似文献   

15.
Tsai SY  Hsu WM  Cheng CY  Liu JH  Chou P 《Ophthalmology》2003,110(6):1089-1095
PURPOSE: The purpose of this study was to determine the prevalence and risk factors for age-related cataracts in a metropolitan elderly Chinese population in Shihpai, Taipei, Taiwan. DESIGN: Population-based cross-sectional study. PARTICIPANTS: A total of 2045 subjects at least 65 years of age were invited to participate, and 1361 (66.6%) participated in the survey. METHODS: An eye examination, including lens opacity grading, was conducted by ophthalmologists using the Lens Opacity Classification System III (LOCS III). A structured questionnaire was used for data collection. Interviewers also collected information on subjects' blood pressure, lifestyle (cigarette smoking and alcohol intake), medical history, and waist and hip circumferences. MAIN OUTCOME MEASURES: Subjects were defined as having age-related cataracts if there was any type of lens opacity with an LOCS III grade of more than 2 in one or both eyes. When both eyes of an individual had age-related cataracts, the more affected eye was used for analysis. RESULTS: Among the 1361 participants, 806 were diagnosed with age-related cataracts. The prevalence was 59.2% (95% confidence interval, 56.6%-61.8%). Women had a higher prevalence of cataracts than men (64.0% vs. 56.1%, P = 0.004). The prevalence of age-related cataracts increased with age (P = 0.001). Nuclear opacity was the most prevalent type (38.9%), followed by cortical opacity (21.9%) and posterior subcapsular opacity (9.2%). On the basis of the final logistic regression model, after controlling for all other covariates, increased age and female gender were factors that were associated with an increased risk for all types of cataracts. Besides age and gender, the most significant risk factor for nuclear cataracts was current cigarette smoking; the significant predictors for cortical cataracts were higher systolic blood pressure, a history of cigarette smoking in the past, and history of diabetes; the significant predictor for posterior subcapsular cataracts was higher systolic blood pressure. CONCLUSIONS: The increasing prevalence of age-related cataracts with age highlights the need to seek appropriate medical services and for preventative interventions. Elderly people often ignore the importance of seeking vision services and care to prevent blindness or visual impairment. These findings suggest that the elderly need to be educated regarding the importance of eye care by physicians and hygiene authorities in Taiwan.  相似文献   

16.
A comparison of two photographic systems for grading cataract   总被引:2,自引:0,他引:2  
Two different systems for classifying lens opacities were compared: the Lens Opacity Classification System version II (LOCS II) and the system developed at Johns Hopkins University. Using the two systems, slit-lamp photographs of the nucleus and retroillumination lens photographs of 100 eyes were graded. Each photograph was graded independently by three trained observers, and the time taken to grade the photographs was similar. Each system uses photographs to define the severity of nuclear opacity and nuclear color, and each showed good interobserver agreement (kappa statistic, greater than 0.6). The method of classifying cortical and posterior subcapsular opacity varied, and although interobserver agreement was acceptable in each system, it was somewhat higher with the Hopkins system. Because different standards and definitions are used to define severity with each system, there was some variation in the classification of individual photographs and corresponding differences in the proportion of photographs in each grade of severity. These data provide a useful cross reference for future comparison of studies using these systems.  相似文献   

17.
AIM: To assess lens thickness measurements with anterior segment-optical coherence tomography (AS-OCT) in comparison with A-scan ultrasonography (A-scan US). METHODS: There were 218 adult subjects (218 eyes) aged 59.2±9.2y enrolled in this prospective cross-sectional study. Forty-three eyes had open angles and 175 eyes had narrow angles. Routine ophthalmic exam was performed and nuclear opacity was graded using the Lens Opacities Classification System III (LOCS III). Lens thickness was measured by AS-OCT (Visante OCT, Carl Zeiss Meditec, Dublin, CA, USA). The highest quality image was selected for each eye and lens thickness was calculated using ImageJ software. Lens thickness was also measured by A-scan US. RESULTS: Interclass correlations showed a value of 99.7% for intra-visit measurements and 95.3% for inter-visit measurements. The mean lens thickness measured by AS-OCT was not significantly different from that of A-scan US (4.861±0.404 vs 4.866±0.351 mm, P=0.74). Lens thickness values obtained from the two instruments were highly correlated overall (Pearson correlation coefficient=0.81, P<0.001), and in all LOCS III specific subgroups except in grade 5 of nuclear opacity. Bland-Altman analysis revealed a 95% limit of agreement from -0.45 to 0.46 mm. Lens thickness difference between the two instruments became smaller as the lens thickness increased and AS-OCT yielded smaller values than A-scan US in thicker lens (β=-0.29, P<0.001) CONCLUSION: AS-OCT-derived lens thickness measurement is valid and comparable to the results obtained by A-scan US. It can be used as a reliable noncontact method for measuring lens thickness in adults with or without significant cataract.  相似文献   

18.
Age-corrected normal values for the Opacity Lens Meter (OLM) 701 were established by measuring 1598 eyes of 799 healthy volunteers. This study revealed a remarkable age-relation for the normal values. The average readings of the OLM of the 30-year-old subjects were around 10 units whereas the average for the 65-year-olds was close to 20 units. The best fit of the opacity vs. age was a quadratic function. The interindividual variation was small in the young and quite large in the older population. The correlation between contralateral eyes was high (R=0.93).  相似文献   

19.
Purpose: Determination of lens opacity is important in aging glaucoma patients, because sensory testing may be influenced by increasing lens opacity. Purpose of this study was to measure lens opacity in normals and glaucoma patients using two different techniques, to compare both methods, and to correlate the results with contrast sensitivity testing. Methods: 94 glaucomatous eyes, 47 ocular hypertensive eyes, and 79 control eyes were studied using the following devices: opacity lens meter (OLM, objective back scatter method), stray light meter (SLM, subjective forward scatter using flicker light), and temporal contrast sensitivity (full-field flicker test). SLM results were separately analyzed at the lower and upper flicker disappearance. All subjects were younger than 66 years and had no significant cataracts. Results: In patients and in normal subjects OLM readings and SLM findings elicited at the upper disappearance point are significantly correlated with age and with each other (R>0.45, P<0.001), while SLM at the lower disappearance point shows no such correlation. In normals, but not in patients, SLM at the lower disappearance point is significantly correlated with temporal contrast sensitivity. Conclusions: Both devices can be used for quantifying lens opacity in glaucoma. SLM readings with increasing light intensity at the lower disappearance point seems to be more influenced by the individual flicker sensitivity than determination of the upper flicker disappearance. Therefore, using the SLM in glaucoma patients, the threshold measurements based on the upper disappearance of the flicker should be used instead of the suggested mean threshold measurements.  相似文献   

20.
PurposeUltraviolet B (UVB) has been well documented to induce capsular cataracts; however, the mechanism of the lens epithelial cell–mediated repair process after UVB irradiation is not fully understood. The purpose of this study was to better understand lens epithelial cell repair after UVB-induced epithelium damage.MethodC57BL/6J mice were irradiated by various doses of UVB. Lens morphology and lens capsule opacity were monitored by slit lamp, darkfield microscopy, and phase-contrast microscopy. Lens epithelial cell mitotic activation and cell apoptosis were measured by immunohistochemistry. Lens epithelial ultrastructure was analyzed by transmission electron microscopy.ResultsUVB irradiation above a dose of 2.87 kJ/m2 triggered lens epithelial cell apoptosis and subcapsular cataract formation, with a ring-shaped structure composed of multilayered epithelial cell clusters manifesting a dense ring-shaped capsular cataract. The epithelial cells immediately outside the edge of the ring-shaped aggregates transitioned to mitotically active cells and performed wound healing through the epithelialization process. However, repairs ceased when lens epithelial cells made direct contact, and scar-like tissue in the center of the anterior capsule remained even by 6 months after UVB irradiation.ConclusionsOur present study demonstrates that normally quiescent lens epithelial cells can be reactivated for epithelialization repair in response to UV-induced damage.  相似文献   

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