Non-compliance with lens care and maintenance in diabetic contact lens wearers

We hypothesize that diabetic contact lens wearers may represent a special group displaying higher levels of compliance with their lens care regimens as a result of learned behaviour relating to maintenance of their diabetic condition. To test this hypothesis, a prospective, single centre, controlled, masked study was performed whereby 29 diabetic contact lens patients and 29 non-diabetic control subjects were issued with disposable hydrogel contact lenses and a multipurpose lens care regimen. All participants were given identical instruction on lens care and maintenance. Compliance levels were assessed at a 12-month aftercare appointment by demonstration and questionnaire. Twenty-four different aspects of compliance were scored, 12 by observation and 12 by questionnaire report, of which only two showed a significant difference between the diabetic and control groups. Although the combined population of contact lens wearers was generally compliant, there were examples of non-compliance in both groups. Neither the duration of diabetes nor the degree of metabolic control appeared to have a significant effect on compliance. The results suggest that eye care practitioners cannot assume that diabetic patients will be more compliant with contact lens care and maintenance than non-diabetic patients.     

眼科成像设备在接触镜适配中的应用

接触镜在全球的应用日益广泛,配适方法的不断进步是目前接触镜安全性、舒适性不断提高的原因之一。在接触镜适配过程中,越来越多的先进影像技术被运用于指导接触镜的配适,这些技术的出现简化了接触镜适配的过程,为临床医生进行简便、准确、个性化的接触镜适配提供了帮助,也为接触镜的个性化设计提供了参考数据。     

Extended Wear Silicone Contact Lenses in Children with Cataracts

Thirty-two patients, ranging in age from three weeks to 22 years, were fitted with an extended wear 100% silicone lens. The longest period of time a lens remained in the eye without being removed was 120 days. Most lenses were worn an average of six weeks before cleaning was required. No cases of infection or corneal edema were observed that required discontinuing use of the lens.     

亲水性软性角膜接触镜所致角膜新生血管临床观察

本文观察了因配戴软性亲水性角膜接触镜而产生角膜新生血管的３３例５９眼，对角膜新生血管的发病机制进行了探讨，指出角膜新生血管的发生与戴镜年限、连续戴镜时间、角膜与镜片的匹配有密切关系，对于此并发症的治疗采用停戴接触镜取得较好效果。     

A clinical comparison of the Johnson & Johnson Acuvue,the Barnes-Hind Calendar and the Bausch & Lomb Medalist disposable contact lenses

We compared the clinical performacne of three brands of disposable contact lenses availble in Australia by refitting 82 Johnson & Johnson Acuvue wearers with either Barnes-Hind Calendar or Bausch & Lomb Medalist lenses. Subjective lens assessments were analysed with regard to patient factors. Many of these factors wer not significant for predicting the success of a lens but overall lens preference and preference on the basis of comfort, handling and quality of vision were predictable from a history of keratitis, wearing mode or lens power. However, High individual variations did occur. Fitting success is imporved by following some simple guidelines but is maximised obly by trialing more than one lens type.     

Early Australian contact lens practice

Recently, a number of papers have addressed the international history of contact lens practice. In this paper, the unique features of early Australian contact lens practice are reviewed. The most important landmark was the introduction of ground glass haptic lenses to Australia during the 1920s. However, Australian ophthalmologists subsequently entered into an exclusive trade agreement with the manufacturers, Zeiss of Germany. Only when contact lens development entered the age of plastics, during the 1940s, were Australian optometrists able to readily prescribe contact lenses.     

Clinic study on silicone hydrogel contact lenses used as bandage contact lenses after LASEK surgery

AIM: To compare the clinical performance of two types of silicon hydrogel contact lenses used as bandage lenses after LASEK surgery. METHODS: A prospective, double-masked study was conducted on 42 eyes of 21 patients who received binocular LASEK surgeries. The interocular difference in spherical equivalent power was less than -1.50D. Patients were randomly assigned to wear Galyfilcon A (Lens A) bandage contact lens in one eye and Balafilcon A (Lens B) in the fellow eye after the surgery. The responses to a subjective questionnaire on comfort of wearing, corneal epithelial status, conjunctival hyperemia, limbal neovascularization, lens fitting and contact lens debris were assessed 1 and 5 days postoperatively. Corneal endothelium was assessed before and 5 days after the surgery upon bandage lens removal. RESULTS: There was no difference between the two groups in terms of conjunctival hyperemia, limbal neovascularization, contact lens fitting, corneal epithelial status, corneal endothelium cell density (CD) and endothelium cell size (CS) at any postoperative visit. Complaints of discomfort, including foreign body sensation, pain and intolerance were statistically more among Lens B wearers at any postoperative visit (P<0.05). Lens B appeared to attract much more debris than Lens A at the 5-day post-operative follow-up visit (P<0.01). CONCLUSION: The two types of silicon hydrogel lenses investigated in this study demonstrated similar clinical performance in terms of corneal responses and lens fitting. However, Lens A showed a better performance in terms of comfort of wearing and deposit resistance.     

Contact lens compliance amongst soft contact lens users

目的:从卫生和镜片、镜片盒及镜片护理液的更换来调查隐形眼镜配戴者的依从性.方法:以每天配戴镜片至少8h、持续配戴≥6mo的隐形眼镜配戴者为研究对象.采用半结构化、经过预先测试和验证的问卷调查表,在接受口头知情同意后评估软性隐形眼镜配戴者的依从性.每位受试者都接受访问,收集有关戴隐形眼镜使用历史的信息.年龄、性别、使用的镜片类型、配戴经验(a)、配戴时间和习惯、一天中持续使用镜片的时间和护理方法的细节都进行了记录.结果:共73名参与者的平均年龄为23.63±5.23y.观察到:依从性最高的项目为镜片清洁和消毒程序(98%);依从性最低的是隐形眼镜配件护理(81%).依从性较差的是:更换镜片盒(41%),检查并丢弃过期的护理液(22%)和未能进行后续随访(22%).镜片配戴的性别、配戴方式、配戴类型以及隐形眼镜使用年限依从性间无统计学差异.结论:这项研究结果证明总体上配戴者依从性良好.然而,在隐形眼镜盒和护理液等镜片配件的护理中,存在一定程度的不遵嘱执行.我们认为有必要考虑改善镜片护理操作依从性的方法.     

Trends in Australian contact lens prescribing during the first decade of the 21st Century (2000–2009)

Purpose: The aim was to document contact lens prescribing trends in Australia between 2000 and 2009. Methods: A survey of contact lens prescribing trends was conducted each year between 2000 and 2009. Australian optometrists were asked to provide information relating to 10 consecutive contact lens fittings between January and March each year. Results: Over the 10‐year survey period, 1,462 practitioners returned survey forms representing a total of 13,721 contact lens fittings. The mean age (± SD) of lens wearers was 33.2 ± 13.6 years and 65 per cent were female. Between 2006 and 2009, rigid lens new fittings decreased from 18 to one per cent. Low water content lenses reduced from 11.5 to 3.2 per cent of soft lens fittings between 2000 and 2008. Between 2005 and 2009, toric lenses and multifocal lenses represented 26 and eight per cent, respectively, of all soft lenses fitted. Daily disposable, one‐ to two‐week replacement and monthly replacement lenses accounted for 11.6, 30.0 and 46.5 per cent of all soft lens fittings over the survey period, respectively. The proportion of new soft fittings and refittings prescribed as extended wear has generally declined throughout the past decade. Multi‐purpose lens care solutions dominate the market. Rigid lenses and monthly replacement soft lenses are predominantly worn on a full‐time basis, whereas daily disposable soft lenses are mainly worn part‐time. Conclusions: This survey indicates that technological advances, such as the development of new lens materials, manufacturing methods and lens designs, and the availability of various lens replacement options, have had a significant impact on the contact lens market during the first decade of the 21st Century.     

Current Australian Contact Lens Practice*

ABSTRACT: A survey was sent to 572 contact lens practitioners in order to ascertain trends in Australian contact lens practice. Replies were obtained from 134 optometrists and 8 ophthalmologists. The results indicate a resurgence of interest in soft lenses, a high usage of toric soft lenses, a dramatic reduction in PMMA usage and an increase in the use of gas permeable lenses. Possible reasons for these apparent trends are discussed.     

Spectral optical coherence tomography: a new imaging technique in contact lens practice

PURPOSE: Spectral optical coherence tomography (SOCT) is a new non-invasive, non-contact, high-resolution technique, which provides cross-sectional images of objects that weakly absorb and scatter light. The aim of this article is to demonstrate the application of SOCT to imaging of eyes fitted with contact lenses. METHODS: Nine eyes of six different subjects fitted with various contact lenses have been examined with a slit-lamp and a prototype SOCT instrument. RESULTS: Our SOCT system provides high-resolution (4-6 mum longitudinal, 10 mum transversal) tomograms composed of 3000-5000 A-scans with acquisition time of 100-250 ms. The quality of the images is adequate for detailed evaluation of contact lens fit. Design, shape and lens edge position were assessed, and complications of contact lens wear could be visualized. Thickness of the lens, corneal epithelium and stroma as well as the space between the lens and the eye surface have been measured. CONCLUSIONS: SOCT allows high-resolution, cross-sectional visualization of the eye fitted with a contact lens. The ability to carry out a detailed evaluation of the fitting relationship between the lens and the ocular surface might be useful in research and optometric practice. SOCT can also be helpful in diagnosis, evaluation and documentation of contact lens complications.     

Modified suturing contact lens for penetrating keratoplasty.

The authors have previously described a suturing contact lens that protects the corneal endothelium by aiding in the maintenance of the anterior chamber during penetrating keratoplasty. This report describes structural modifications of the suturing contact lens, which improve its stability and effectiveness. An additional configuration for use in corneal lacerations is presented.     

圆锥角膜患者使用Rose K2软性角膜接触镜的临床表现

目的:评价圆锥角膜患者使用Rose K2软性角膜接触镜的舒适度及视觉表现.方法:横断面研究.50例患者(50眼)接受全面的眼科检查,包括屈光度、裸眼视力(UCVA)、最佳矫正视力(BCVA)、裂隙灯显微镜及眼底检查、泪膜破裂时间(BUT)、角膜地形图和对比敏感度.戴镜后,测量最佳戴镜矫正视力(BCLCVA)、对比敏感度及舒适度通过平均视觉模拟量(VAS)呈现.结果:患者平均年龄为26.2依6.0 (16 ~39) y.使用Rose K2软性角膜接触镜 UCVA,BCVA,和 BCLCVA 的平均logMAR值依次为0.61依0.37 (0.15 ~1.3),0.42依0.32 (0~1.3) 和0.18依0.20 (0 ~1.3).使用接触镜后视敏度显著提高(P<0.05),在明视和暗视条件下,对比敏感度数值明显增加(P<0.05).Rose K2软性角膜接触镜的视觉模拟量(VAS)值为8.02依1.64(5~10).结论:圆锥角膜患者使用Rose K2软性角膜接触镜能够改善视力,对比敏感度以及舒适度.     

Contact lens practice in Australia 1988–1989

Contact lens practitioners completed an annual survey of their prescribing patterns, usage of care solutions and attitudes to extended wear (EW). The survey period was July 1 1988 to June 30 1989 and the results were compared to those of previous, similar surveys. Many results were close to those in previous surveys, including the average number of pairs of lenses prescribed (95 new, 30 replacement), the proportion of contact lens fittings which were refits (40 per cent), the percentage of lenses prescribed which were soft (83 per cent) and the proportions of toric (soft 23 per cent, hard five per cent) and tinted (soft 39 per cent, hard 71 per cent) lenses prescribed. Results which differed markedly from previous surveys included the number of pairs of replacement lenses sold and the percentage of contact lens patients who were presbyopic. More than 90 per cent of lenses prescribed for EW were soft, although approximately 20 per cent of practitioners indicated that they would prefer to fit rigid gas permeable materials for EW. EW lenses were worn only on a true EW basis in six per cent of cases.     

Silsoft extended wear contact lenses in pediatric aphakia

Fifty pediatric aphakic patients, ranging in age from 7 days to 11 years, were fitted with the Silsoft extended wear contact lens. Compared to other extended wear lenses, the Silsoft lens has several advantages. These include easier handling, a less traumatic fitting procedure for the child, the use of fluorescein for evaluation of the lens-cornea relationship and a low loss rate. This lens appears to be safe, with no permanent adverse effects on the cornea.     

新型的持续配戴高DK值的角膜接触镜

目的：随着镜片材料和制作工艺的高速发展，更加安全地过夜配戴角膜接触镜已逐渐成为可能。方法：对近年来涉及持续配戴高DK值角膜接触镜的一些研究论文进行综述。结果：新型的高DK值的硅胶和硅氟化物水凝胶镜片与传统的HEMA镜片相比，氧传导性高出6倍，这种新材料的镜片能够从根本上避免任何与组织缺氧有关的并发症。另一个明显的差异在于：新一代的硅胶镜片有更高的系数。而且在生理反应、匹配以及易操作性方面，与传统的低DK值镜片也明显不同。另外，尽管与组织缺氧相关的并发症不再存在，但是由于镜片覆盖在角巩缘360度范围，所以潜在的炎症反应以及机械性的损伤仍然不可避免。因此，制造者对涉及角膜生理反应的评估和对配适关系重要性的理解是这些新镜片获得成功过夜配戴的关键。结论：作为眼保健的从业者，视光医师必须了解持续配戴镜片的新进展情况、新材料潜在的副反应和配适特性。     

软性角膜接触镜在治疗角膜穿孔中的应用

目的评价软性角膜接触镜在治疗角膜穿孔中的效果。方法9例(9眼)新鲜角膜穿孔伴前房消失,其中角膜溃疡致穿孔7例,角膜穿孔伤2例。所有患眼均配戴软性角膜接触镜治疗。戴镜期间根据不同病例选择用药,接触镜每周消毒1次。结果所有患眼1~2 d内前房恢复,22~40 d角膜溃疡愈合,5例病灶见新生血管长入,1例角膜溃疡前房反复消失,后行穿透性角膜移植,2例角膜穿孔伤口对合整齐。结论软性角膜接触镜在治疗角膜小穿孔中是一种安全有效的辅助治疗方法。     

软性虹彩片联合透气性半硬性角膜接触镜矫治外伤性无虹膜无晶状体眼

目的 评价软性虹彩片联合透气性半硬性角膜接触镜(RGPCL)对外伤性无虹膜无晶状体眼的矫治效果.设计回顾性病例系列.研究对象 角膜内皮细胞密度在2500个/mm2以上外伤性无虹膜无晶状体眼患者59例(59眼).方法患者联合戴用软性虹彩片和RGPCL,比较初诊时的插片视力和RGPCL矫正视力,随诊5年,非接触性角膜内皮计...     

Hydrogel lens wettability and deposition in vivo

Background : Wearing a hydrogel contact lens disrupts tear film stability, resulting in a low non-invasive surface drying time (NISDT) on the lens front surface. Reduced wettability causes deposit formation, reducing the quality of vision and lens comfort. This investigation determined the effect of commercially available HEMA-based materials on pre-lens tear film stability and deposition. Methods : Twenty patients in a randomised, double blind study wore four lenses for eight hours. These lenses were Tefilcon, Polymacon (Group I lenses), Vifilcon A and Etafilcon A (Group IV lenses). Non-invasive surface drying time (NISDT) was measured for each lens type after 10 minutes, one hour, four hours and eight hours wear. Lenses were then removed and examined by scanning electron microscopy. Results : NISDT decreased significantly (p < 0.05) over the eight-hour wear period for all lens types. Group IV lenses showed a slightly, but not clinically significantly, higher NISDT compared to Group I lenses. A greater number of deposits was seen on Vifilcon A and Polymacon compared to Etafilcon A and Tefilcon lenses. Conclusions : Wear decreases lens wettability over eight hours, irrespective of lens type. Higher wettability was seen with Group IV lenses, although the increase was not clinically significant. Wettability was not correlated with the formation of discrete deposits. Deposit formation depends on the composition of the lens base material, its ionic charge, surface topography, water content and wearers' ocular characteristics.     

Contact lens fitting for post-radial-keratotomy residual myopia

Purpose: To formulate guidelines for contact lens fitting following radial keratotomy and to achieve a relationship between contact lens fitting parameters and refractive and keratometric parameters. Methods: Thirty‐five eyes of 30 patients who had post‐radial‐keratotomy residual myopia were evaluated for contact lens fitting. The base curve was selected by ‘hit and trial’ method until a proper fit was achieved, following which an over‐refraction was done and final power of the contact lens obtained. Results: The mean contact lens base curve was 43.04 ± 1.62 D, which was steeper than the postoperative keratometry by 2.35 ± 0.74 D. The base curve and the postoperative keratometry were correlated by regression analysis (r = 0.895, P < 0.001). The mean overall diameter of the contact lenses was 9.64 ± 0.08 mm. The mean contact lens power was 5.81 ± 3.07 D, which was more myopic than the residual myopia by 2.79 ± 1.67 D. Regression analysis showed definite correlation between the contact lens power and postoperative myopia (r = 0.854, P < 0.001). Conclusion: For correction of post‐radial‐keratotomy residual myopia, contact lens fitting parameters can be determined by a regression formula using keratometric and refractive values.