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Fang J, Huang Z, Long Y, Zhu M, Wu Q, Chen X, Xv W, Du C. Retardation of Myopia by Multifocal Soft Contact Lens and Orthokeratology: A 1-Year Randomized Clinical Trial. Eye Contact Lens 2022; 48:328-334. [PMID: 35877183 PMCID: PMC9298149 DOI: 10.1097/icl.0000000000000911] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2022] [Indexed: 11/26/2022]
Abstract
OBJECTIVES This randomized, single-blind, clinical trial compared the effectiveness of multifocal soft contact lenses (MFSCLs), orthokeratology contact lenses (Ortho-kCLs), and single vision spectacles (SVSs) for myopia control. METHODS Sixty-six eligible Chinese subjects, aged 7 to 15 years old with cycloplegic refraction measurements between -1.00 and -8.00 diopters (D), astigmatism not more than 1.00 D, and no history of myopia control treatment, were randomly assigned to wear MFSCLs, Ortho-kCLs, or SVSs for 1 year. For all three groups, baseline measurements of cycloplegic refraction, axial length (AL), and corneal endothelial cell density (CECD) were made. At the 6- and 12-month follow-up visits, changes in cycloplegic refraction, AL, and CECD were measured in the MFSCL and SVS groups. For the Ortho-kCL group, only changes in the AL were measured at 6 and 12 months, and CECD was measured at the 12-month follow-up visit. RESULTS After 1 year of lens wear, myopia progression of the SVS group, -0.938±0.117 D, was greater than that of the MFSCLs group, -0.591±0.106 D (P=0.032). Thus, MFSCLs reduced the rate of myopia progression by 37.0% compared with the SVSs. The AL elongations after 1 year were 0.30±0.03 mm for MFSCLs (P=0.027 vs SVSs), 0.31±0.04 mm for Ortho-kCLs (P=0.049 vs SVSs), and 0.41±0.04 mm for SVSs. Compared with the SVS group, the reduction in AL elongation was 26.8% and 24.4% in the MFSCL and Ortho-kCL groups, respectively. There were no significant differences in CECD among the three groups (P>0.05). CONCLUSIONS Compared with SVSs, wearing MFSCLs and Ortho-kCLs significantly delayed myopia progression. MFSCLs and Ortho-kCLs are safe and promising methods of myopia control (chictr.org number, ChiCTR2100048452).
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Affiliation(s)
- Jianxia Fang
- Department of Ophthalmology (J.F., Y.L., M.Z., Q.W., X.C., W.X., C.D.), The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, P. R. China; and Department of Ophthalmology (Z.H., C.D.), The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang Province, P. R. China
| | - Zhu Huang
- Department of Ophthalmology (J.F., Y.L., M.Z., Q.W., X.C., W.X., C.D.), The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, P. R. China; and Department of Ophthalmology (Z.H., C.D.), The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang Province, P. R. China
| | - Yan Long
- Department of Ophthalmology (J.F., Y.L., M.Z., Q.W., X.C., W.X., C.D.), The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, P. R. China; and Department of Ophthalmology (Z.H., C.D.), The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang Province, P. R. China
| | - Miaomiao Zhu
- Department of Ophthalmology (J.F., Y.L., M.Z., Q.W., X.C., W.X., C.D.), The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, P. R. China; and Department of Ophthalmology (Z.H., C.D.), The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang Province, P. R. China
| | - Qin Wu
- Department of Ophthalmology (J.F., Y.L., M.Z., Q.W., X.C., W.X., C.D.), The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, P. R. China; and Department of Ophthalmology (Z.H., C.D.), The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang Province, P. R. China
| | - Xiaojun Chen
- Department of Ophthalmology (J.F., Y.L., M.Z., Q.W., X.C., W.X., C.D.), The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, P. R. China; and Department of Ophthalmology (Z.H., C.D.), The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang Province, P. R. China
| | - Wei Xv
- Department of Ophthalmology (J.F., Y.L., M.Z., Q.W., X.C., W.X., C.D.), The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, P. R. China; and Department of Ophthalmology (Z.H., C.D.), The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang Province, P. R. China
| | - Chixin Du
- Department of Ophthalmology (J.F., Y.L., M.Z., Q.W., X.C., W.X., C.D.), The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, P. R. China; and Department of Ophthalmology (Z.H., C.D.), The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang Province, P. R. China
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Zada M, Cabrera‐Aguas M, Branley M, Azar D, Watson S. Microbial keratitis associated with long‐term orthokeratology. Clin Exp Ophthalmol 2018; 47:292-294. [DOI: 10.1111/ceo.13386] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 09/01/2018] [Indexed: 11/30/2022]
Affiliation(s)
- Mark Zada
- Department of OphthalmologyConcord Repatriation General Hospital Sydney Australia
| | - Maria Cabrera‐Aguas
- Sydney Eye Hospital Sydney Australia
- Save Sight Institute, University of Sydney Sydney Australia
| | - Michael Branley
- Department of OphthalmologyRoyal North Shore Hospital Sydney Australia
| | - Domit Azar
- Department of OphthalmologyConcord Repatriation General Hospital Sydney Australia
- Concord Clinical SchoolUniversity of Sydney Sydney Australia
| | - Stephanie Watson
- Sydney Eye Hospital Sydney Australia
- Save Sight Institute, University of Sydney Sydney Australia
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Shehadeh-Masha'Our R, Segev F, Barequet I, Ton Y, Garzozi H. Orthokeratology Associated Microbial Keratitis. Eur J Ophthalmol 2018; 19:133-6. [DOI: 10.1177/112067210901900120] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Purpose To report the clinical course, microbiologic findings, treatment, and outcomes of overnight orthokeratology associated microbial keratitis. Methods Four cases of overnight orthokeratology associated microbial keratitis are reported. Results Four patients aged 14–23 years (mean 18 years) who had central or paracentral corneal ulcers were included. Visual acuity at presentation ranged from 20/30 to hand motion. In all cases Pseudomonas aeruginosa was cultured from corneal scrapings or storage solution. In all patients the infection resolved with intensive topical antimicrobial treatment. Final best-corrected visual acuity ranged from 20/25 to 20/200 according to the location, size, and density of the corneal scar, which complicated all cases. Conclusions Infectious keratitis is a significant, visual threatening complication of overnight orthokeratology. Eye care practitioners should be aware of this complication and educate their patients of the importance of lens hygiene and prompt medical care when symptoms or signs of keratitis appear.
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Affiliation(s)
| | - F. Segev
- Meir Hospital-Sackler Faculty of Medicine, Tel Aviv University, Kfar Saba
| | - I.S. Barequet
- Goldschleger Eye Institute, Sheba Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Hashomer - Israel
| | - Y. Ton
- Meir Hospital-Sackler Faculty of Medicine, Tel Aviv University, Kfar Saba
| | - H.J. Garzozi
- Bnai Zion Medical Center, Faculty of Medicine Technion, Haifa
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Infectious keratitis and orthokeratology lens use: a systematic review. Infection 2017; 45:727-735. [PMID: 28534320 DOI: 10.1007/s15010-017-1023-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 05/04/2017] [Indexed: 10/19/2022]
Abstract
PURPOSE Myopia is a prevalent condition among Asians. Orthokeratology lens has gained popularity as a method of myopia control. This systematic review is to summarize the clinical profile of infectious keratitis in association with orthokeratology lens wear. METHODS We searched in the PubMed and EMBASE for articles adopting the search strategy "(orthokeratology lens OR orthokeratology) AND (bacterial eye infection OR keratitis OR cornea ulcer OR microbial keratitis OR bacterial keratitis)", from the start date of the databases to August 23, 2016. Articles reporting infectious keratitis in orthokeratology lens users with data of individual cases were considered eligible for this systematic review. We recorded the outcome measures including method of diagnosis, etiological agents, duration and mode of treatment and treatment outcomes. RESULTS Our literature search yielded 172 papers. After removing duplicated and irrelevant reports, we included 29 articles for data analysis, involving 173 eyes. Among all reported cases, the mean age at presentation was 15.4 ± 6.2 years, with a female preponderance (male-to-female ratio 1:1.7). Positive microbiological cultures were reported in 69.4% of cases, with Pseudomonas aeruginosa and Acanthamoeba being the most common etiological agents. The mean duration of hospitalization was 7.7 ± 6.7 days. Mean LogMAR visual acuity at presentation was 1.17 ± 0.78, increased to 0.33 ± 0.41 at final visit (p < 0.001). CONCLUSIONS Despite early intervention and treatment, the majority of infections resulted in the formation of corneal scars and almost 10% of eyes needed surgical treatment. Timely awareness and treatment of keratitis should be emphasized to the users.
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Abstract
Objectives: The aim of this review is to evaluate the ocular safety of orthokeratology (OrthoK) treatment of myopia correction and retardation. Data Sources: Clinical studies published in English and Chinese were identified from MEDLINE, EMBASE CNKI, CQVIP, and WANFANG DATA (all from 1980 to April 2015). The reference lists of the studies and the Science Citation Index were also searched. Selection Criteria: Relevant clinical studies including case series, case reports, patient/practitioner surveys, retrospective and prospective cohort studies, and clinical trials were all included in the review. The material of OrthoK lenses was limited to gas-permeable lens. Main Results: This review incorporated a total of 170 publications, including 58 English and 112 Chinese literature. The risk of microbial keratitis in overnight OrthoK was similar to that of other overnight modality. The most common complication was corneal staining. Other clinically insignificant side effects included epithelial iron deposit, prominent fribrillary lines, and transient changes of corneal biomechanical properties. There was no long-term effect of OrthoK on corneal endothelium. Conclusions: There is sufficient evidence to suggest that OrthoK is a safe option for myopia correction and retardation. Long-term success of OrthoK treatment requires a combination of proper lens fitting, rigorous compliance to lens care regimen, good adherence to routine follow-ups, and timely treatment of complications.
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Aldebasi YH, Mohamed HA, Aly SM. Histopathological Studies on Rabbits Infected by Bacteria Causing Infectious Keratitis in Human through Eye Inoculation. Int J Health Sci (Qassim) 2014; 8:257-67. [PMID: 25505861 DOI: 10.12816/0023978] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
AIM This study aimed to investigate the pathogenic effect of bacteria causing infectious keratitis among patients through experimental study conducted on rabbits' eyes with the aid of histopathology as eye infection is a common disease in developing countries that may complicate to loss of vision. METHODOLOGY 100 swab samples were collected from human infected eyes, at Qassim region during 2012, for the isolation of Pseudomonas aeruginosa and Staphylococcus aureus. The isolated pathogenic bacteria were tested to various antibiotics using some selected antibiotics discs through agar-well diffusion method. Then, experimental study conducted on 27 rabbits. The rabbits were divided randomly into three equal groups, each containing 9 rabbits. Rabbits of group (1) served as control group (Negative Control) and their eyes were inoculated with the buffer only. Rabbits of group (2) were inoculated through eyes with the isolated Pseudomonas aeruginosa. Rabbits of group (3) were inoculated through eyes with the isolated Staphylococcus aureus. RESULTS Out of 100 collected swab samples from human infected eyes, Pseudomonas aeruginosa and Staphylococcus aureus were isolated with a total percentage of 25.21% and 15.65%; respectively and used in this study. Both bacterial isolates were sensitive to Gentamicin and Cefuroxime. Clinically, experimentally infected rabbits by Pseudomonas aeruginosa, revealed varying degree corneal abrasions, corneal abscess and dense corneal opacity. Histopathologically, at 3(rd) day post-infection (PI), the cornea revealed polymorpho-nuclear cells infiltration with loss of the outer epithelial lining. At 7(th) day PI, neutrophils were seen in the stroma. At 15(th) day PI, proliferation of fibroblasts and new vascularisation were seen in the stroma. Clinically, rabbits experimentally infected with Staphylococcus aureus, revealed corneal ulcers and focal abscesses. Histopathologically, at 3(rd) and 7(th) day PI, the cornea revealed edema and infiltration of leukocytes. At 15(th) day PI, hyperplasia of corneal epithelium and proliferation of keratocytes were evident. The liver and kidneys of experimented rabbits revealed no remarkable histopathological alterations along the period of experiment. CONCLUSION Pseudomonas aeruginosa and Staphylococcus aureus are common eye infection in human, both induced severe lesions in the eyes of rabbits that could interfere with vision, therefore, strict measures to control these infections in human is recommended.
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Affiliation(s)
- Yousef H Aldebasi
- Dept of Optometry, College of Applied Medical Sciences, Qassim University, KSA.Dept of Pathology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Hala A Mohamed
- Dept of Optometry, College of Applied Medical Sciences, Qassim University, KSA.Dept of Pathology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Salah M Aly
- Dept of Medical Laboratories, College of Applied Medical Sciences, Qassim University, KSA.Dept of Pathology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
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Wan KHN, Jhanji V, Young AL. Orthokeratology lens related infections. World J Ophthalmol 2014; 4:63-70. [DOI: 10.5318/wjo.v4.i3.63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 05/21/2014] [Accepted: 06/27/2014] [Indexed: 02/06/2023] Open
Abstract
Orthokeratology is a reversible technique that temporarily changes the curvature of the cornea with the aim of addressing refractive errors. The United States Food and Drug Administration (FDA) granted approval for using reverse geometry contact lenses to correct myopia without any age restriction. Information from the pre-market applications to the FDA was rated as level II evidence. Another unapproved use of overnight orthokeratology is for the prevention of myopic progression. Although orthokeratology is advocated to reduce myopic progression, there are limited long-term studies with substantial evidence of its benefits. Much of this evidence comes from non-robust experimental studies using historical or self-selected controls with relative high dropout rates. Although some positive results have been published in temporarily reducing the myopic refractive error and its progression, the use of these lenses can be associated with serious complications such as microbial keratitis. Microbial keratitis is a potentially vision-threatening adverse response associated with contact lens wear. In fact, contact lens wear has been shown to be the predominant risk factor of microbial keratitis in some developed countries. Most of the published cases on overnight orthokeratology related microbial keratitis occurred in children or adolescents. Parents considering orthokeratology must make an informed decision about its temporary benefit and its potential for permanent loss of vision. The ophthalmic community should be reminded of the potential complications of orthokeratology.
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Microbial Keratitis Profile at a University Hospital in Hong Kong. INTERNATIONAL SCHOLARLY RESEARCH NOTICES 2014; 2014:689742. [PMID: 27433502 PMCID: PMC4897357 DOI: 10.1155/2014/689742] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 10/05/2014] [Accepted: 10/22/2014] [Indexed: 11/17/2022]
Abstract
Purpose. To evaluate the recent trends in demographics, risk factors, and microbiological profiles of microbial keratitis at a university hospital in Hong Kong. Design. Retrospective review. Methods. The medical records of 51 patients admitted to the Prince of Wales Hospital for microbial keratitis from January 2010 to June 2012 were reviewed. Demographics, risk factors, clinical features, microbiological results, and treatment were recorded. Data was analyzed and compared to our historical sampled data collected 11 years ago. Results. The mean age of patients was 41.6 ± 20.3 years. Contact lens use was the major risk factor (45%), followed by injury (12%). The culture positive rate was 59%, of which 37% were Gram-positive organisms and 53% were Gram-negative organisms. Pseudomonas aeruginosa (50%) and coagulase-negative Staphylococcus (13%) were the most commonly isolated pathogens. No resistance to fluoroquinolones was identified. Conclusions. Our study showed that contact lens wear remained the major risk factor for microbial keratitis in Hong Kong and Pseudomonas aeruginosa remained the commonest bacterium isolated. This is comparable to our historical data and other studies conducted in East Asia.
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Young AL, Leung KS, Tsim N, Hui M, Jhanji V. Risk factors, microbiological profile, and treatment outcomes of pediatric microbial keratitis in a tertiary care hospital in Hong Kong. Am J Ophthalmol 2013; 156:1040-1044.e2. [PMID: 23972308 DOI: 10.1016/j.ajo.2013.06.019] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 06/10/2013] [Accepted: 06/11/2013] [Indexed: 11/25/2022]
Abstract
PURPOSE To report the risk factors and microbiological profile of pediatric microbial keratitis cases in a tertiary care hospital in Hong Kong. DESIGN Retrospective study. METHODS Case records of patients <18 years old with microbial keratitis were reviewed over a period of 10 years, between January 2001 and December 2010. Risk factors, microbiological profile, and treatment outcomes were analyzed. RESULTS Overall, 18 patients (13 female, 5 male) with unilateral microbial keratitis were included. The mean age was 12.4 years (range: 3-17 years). The most commonly associated risk factor was contact lens wear (15, 83.3%). Seven cases (38.8%) were associated with orthokeratology lenses. Two cases (11.1%) were related to intrinsic keratopathy and 1 case (5.5%) was infected secondary to trauma. Microbiological culture was positive in 16 cases (88.8%). Overall, Pseudomonas sp. was the most commonly isolated organism (10/16, 62.5%), followed by coagulase-negative Staphylococcus (5/16, 31.2%) and Corynebacterium sp. (2/16, 12.5%). All cases responded to intensive medical management with topical antibiotics. One case with posttraumatic keratitis required stepped surgeries with initial tectonic penetrating keratoplasty followed by lens aspiration and retinal detachment repair. At the last follow-up, 13 out of 17 eyes (76.5%) had best-corrected visual acuity ≥20/40. CONCLUSIONS Contact lens wear was the most commonly encountered risk factor for the occurrence of microbial keratitis in the pediatric age group in our setting. Orthokeratology remains one of the leading causes of contact lens-related infections. The majority of the cases responded to medical management.).
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Quantitative evaluation of night vision and correlation of refractive and topographical parameters with glare after orthokeratology. Graefes Arch Clin Exp Ophthalmol 2011; 249:1519-26. [PMID: 21562891 DOI: 10.1007/s00417-011-1696-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2010] [Revised: 02/15/2011] [Accepted: 03/22/2011] [Indexed: 10/18/2022] Open
Abstract
PURPOSE To evaluate night vision disturbance and investigate correlations between pre- and post-treatment parameters and glare scores in orthokeratology patients. METHODS Twenty-eight right eyes of 28 patients were enrolled in this study. Corneal topography and a night vision test (NVT) to evaluate the extent of glare were performed after orthokeratology. From the corneal topography, two indices [surface regularity index (SRI) and surface asymmetry index (SAI)] were calculated. Fourier analysis was performed on the topographic data from the central 6 mm, and data were decomposed into asymmetric and higher order components for analysis. RESULTS There was no correlation between the glare score and pre-treatment keratometric value, pre-treatment cylinder, post-treatment sphere, and post-treatment cylinder. However, there was a statistically significant correlation between pre-treatment sphere and glare score (Pearson correlation coefficient, r = -0.54, p < 0.01). SRI and SAI significantly correlated with glare score (SRI: r = 0.52, p < 0.01, SAI: r = 0.41, p < 0.05). Higher order and asymmetric components were also significantly correlated with glare score (asymmetry: r = 0.61, p < 0.01, higher order: r = 0.67, p < 0.001). CONCLUSIONS The glare score was significantly correlated with corneal irregularity, and appeared to be a beneficial parameter for assessment of night vision performance in patients receiving orthokeratology.
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Microbial contamination of contact lenses, lens care solutions, and their accessories: a literature review. Eye Contact Lens 2010; 36:116-29. [PMID: 20168237 DOI: 10.1097/icl.0b013e3181d20cae] [Citation(s) in RCA: 161] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE A contact lens (CL) can act as a vector for microorganisms to adhere to and transfer to the ocular surface. Commensal microorganisms that uneventfully cohabitate on lid margins and conjunctivae and potential pathogens that are found transiently on the ocular surface can inoculate CLs in vivo. In the presence of reduced tissue resistance, these resident microorganisms or transient pathogens can invade and colonize the cornea or conjunctiva to produce inflammation or infection. METHODS The literature was reviewed and used to summarize the findings over the last 30 years on the identification, enumeration, and classification of microorganisms adherent to CLs and their accessories during the course of normal wear and to hypothesize the role that these microorganisms play in CL infection and inflammation. RESULTS Lens handling greatly increases the incidence of lens contamination, and the ocular surface has a tremendous ability to destroy organisms. However, even when removed aseptically from the eye, more than half of lenses are found to harbor microorganisms, almost exclusively bacteria. Coagulase-negative Staphylococci are most commonly cultured from worn lenses; however, approximately 10% of lenses harbor Gram-negative and highly pathogenic species, even in asymptomatic subjects. In storage cases, the incidence of positive microbial bioburden is also typically greater than 50%. All types of care solutions can become contaminated, including up to 30% of preserved products. CONCLUSIONS The process of CL-related microbial keratitis and inflammation is thought to be preceded by the presence or transfer or both of microorganisms from the lens to the ocular surface. Thus, this detailed understanding of lens-related bioburden is important in the understanding of factors associated with infectious and inflammatory complications. Promising mechanisms to prevent bacterial colonization on lenses and lens cases are forthcoming, which may decrease the incidence of microbially driven CL complications.
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Abstract
PURPOSE The purpose of this study was to investigate the influence of overnight orthokeratology on corneal sensation. METHODS A prospective study was conducted in 34 eyes of 17 patients undergoing overnight orthokeratology. Their ages ranged from 21 to 33 years (23.5 +/- 3.2 years, mean +/- standard deviation). The logarithm of minimum angle of resolution of uncorrected visual acuity at baseline ranged from 0.22 to 1.52 (0.71 +/- 0.32), and myopic refractive error ranged from -1.00 to -4.00 D (-2.15 +/- 0.90 D). Corneal sensation was measured using the Cochet-Bonnet esthesiometer before and 3 months after the start of treatment, and each eye was tested at 5 different corneal locations: one central point and 4 peripheral points at the superior, inferior, temporal, and nasal positions 2 mm away from the limbus. RESULTS Overnight orthokeratology significantly reduced corneal sensation from 58.24 +/- 6.14 mm at baseline to 49.12 +/- 13.90 mm at 3 months after the start of treatment at the central point (P = 0.0003, Wilcoxon signed-rank test), from 58.24 +/- 6.14 to 47.65 +/- 14.37 mm at the superior point (P = 0.0002), from 57.50 +/- 6.43 to 48.09 +/- 14.82 mm at the inferior point (P = 0.0004), from 58.24 +/- 6.14 to 50.44 +/- 13.73 mm at the temporal point (P = 0.0009), and from 57.65 +/- 6.54 to 48.68 +/- 14.84 mm at the nasal point (P = 0.0022). There were no significant differences in corneal sensation among these 5 points 3 months after the treatment (P = 0.9549, Kruskal-Wallis test). The induced change in corneal sensation at the central cornea was further analyzed in relation to the amount of myopic correction. There was no significant correlation between the loss of corneal sensation and the amount of myopic correction (r = -0.211, P = 0.2245, Spearman rank correlation). CONCLUSIONS Overnight orthokeratology significantly reduced corneal sensation at both central and peripheral locations, and the reduction was not correlated with the amount of myopic correction. At present, the clinical significance of this sensory loss is not clear, but practitioners should take this effect into account in the practice of orthokeratology.
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Differences between overnight and long-term wear of orthokeratology contact lenses in corneal contour, thickness, and cell density. Cornea 2009; 28:271-9. [PMID: 19387227 DOI: 10.1097/ico.0b013e318186e620] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE To investigate changes in corneal topography and morphology in human eyes wearing orthokeratology (OK) lenses for overnight and over a 5-year period. MATERIALS AND METHODS Fifty-six adults with moderate myopia were assigned to 2 groups based on age matching: 5-year lens wear (n = 26, 51 eyes) and 1-night lens wear (n = 30, 60 eyes). All subjects wore reverse-geometry OK lenses with the eyes before 1-night lens wear serving as a control to both the groups. Visual acuity, slit-lamp biomicroscopy, confocal microscopy, and corneal topography were assessed before and after lens wear. RESULTS Visual acuity was improved satisfactorily with flattening of the central cornea in both lens wear groups. Corneal thickness increased extensively in the 1-night lens wear group but only paracentrally in the 5-year lens wear group. Central epithelial thinning with a decreased density of the basal cells was only observed in the 5-year group. Keratocyte density was reduced throughout the entire corneal thickness for the 2 groups. Endothelium was normal in density and morphology for the 2 groups. CONCLUSIONS Short-term and long-term OK lens wear can effectively correct myopia by flattening the cornea. The flattened cornea in the short-term lens wear is mainly because of the thickening of the midperipheral cornea. In the long-term lens wear, however, this change is associated with thickening of the midperipheral cornea and thinning of the central corneal epithelium.
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Safety of Overnight Orthokeratology for Myopia. Ophthalmology 2008; 115:2301-2313.e1. [DOI: 10.1016/j.ophtha.2008.06.034] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2008] [Accepted: 06/26/2008] [Indexed: 11/19/2022] Open
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Prophylactic and therapeutic efficacy of a fully human immunoglobulin G1 monoclonal antibody to Pseudomonas aeruginosa alginate in murine keratitis infection. Infect Immun 2008; 76:4720-5. [PMID: 18644881 DOI: 10.1128/iai.00496-08] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Treatment of ulcerative keratitis due to Pseudomonas aeruginosa is difficult, time-consuming, and uncomfortable owing to the need for the frequent application of antibiotic drops to the infected corneal surface. We examined here whether a fully human immunoglobulin G1 monoclonal antibody (MAb) specific to the conserved alginate surface polysaccharide of P. aeruginosa could mediate protective immunity against typically nonmucoid strains isolated from human cases of keratitis. MAb F429 effectively opsonized alginate-positive, but not alginate-negative, nonmucoid strains in conjunction with phagocytes and complement. Prophylactic administration of MAb F429 18 h prior to infection with two clinical isolates significantly reduced bacterial levels in the eye and the associated corneal pathology. Along similar lines, systemic intraperitoneal injection, as well as topical application of the MAb onto the infected eye, starting 8 h postinfection in both experimental protocols resulted in significant reductions in bacteria in the eye, as well as minimizing pathological damage to the cornea. These findings indicate that MAb F429 could be useful as an additional therapeutic component for the treatment of P. aeruginosa keratitis.
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Choo JD, Caroline PJ, Harlin DD, Papas EB, Holden BA. Morphologic changes in cat epithelium following continuous wear of orthokeratology lenses: A pilot study. Cont Lens Anterior Eye 2008; 31:29-37. [PMID: 17913568 DOI: 10.1016/j.clae.2007.07.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2007] [Revised: 07/06/2007] [Accepted: 07/11/2007] [Indexed: 10/22/2022]
Abstract
PURPOSE To investigate the sequence of morphologic changes over time in cat epithelium during continuous wear of orthokeratology lenses. METHODS Four 2-year-old female cats were used; one served as a no lens wear control and three wore custom designed Paragon CRT lenses for myopic and hyperopic correction in the right and left eyes, respectively. Lenses were worn continuously and animals were euthanased after 4h, 8h and 14 days. Corneal tissue was fixed then stained with hematoxylin and eosin for histologic evaluation and measurement of epithelial thickness. RESULTS Average epithelial thickness of control eyes in the centre (38+/-1 microm) and mid-periphery (3.0 mm from the centre, 38+/-2 microm) of the cornea was similar. Epithelial thickness in myopic corrected eyes showed progressive thinning in the centre and progressive thickening in the mid-periphery with increased lens wearing time. Hyperopic corrected eyes showed the opposite pattern of progressive epithelial thickening in the centre and thinning in the mid-periphery with lens wearing time. CONCLUSIONS The epithelium appears to play a major role in the changes induced by orthokeratology lenses. The epithelial effects were dependent on time and lens design. Further studies are needed to determine the mechanisms responsible for these changes.
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17
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Lee JE, Hahn TW, Oum BS, Choi HY, Yu HS, Lee JS. Acanthamoeba keratitis related to orthokeratology. Int Ophthalmol 2007; 27:45-9. [PMID: 17377749 DOI: 10.1007/s10792-007-9055-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2006] [Accepted: 02/07/2007] [Indexed: 12/15/2022]
Abstract
PURPOSE To report four cases of Acanthamoeba keratitis related to the overnight wearing of orthokeratology lenses. METHODS Four patients had histories of overnight wearing of orthokeratology lenses when they presented with corneal ulcers. They had used a contact lens care system irregularly with tap water. RESULTS The organism isolated by corneal scraping was Acanthamoeba. The patients were treated with polyhexamethylene biguanide (PHMB) and chlorhexidine, resulting in a resolution of ocular inflammation. CONCLUSION The risk of Acanthamoeba keratitis as a potential complication of overnight orthokeratology should be considered, especially in patients with over one-year duration of contact lens wearing. Careful contact lens management is needed and tap-water rinsing should be eliminated from the lens care regimen.
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Affiliation(s)
- Ji-Eun Lee
- Department of Ophthalmology, College of Medicine, Pusan National University, 1-10, Ami-Dong, Seo-Ku, Pusan 602-739, Korea
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18
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Lee SJ, Jeong HJ, Lee JE, Lee JS, Xuan YH, Kong HH, Chung DI, Ock MS, Yu HS. Molecular characterization of Acanthamoeba isolated from amebic keratitis related to orthokeratology lens overnight wear. THE KOREAN JOURNAL OF PARASITOLOGY 2007; 44:313-20. [PMID: 17170573 PMCID: PMC2559130 DOI: 10.3347/kjp.2006.44.4.313] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
In an effort to characterize, on the molecular scale, the Acanthamoeba initially isolated from the cornea of an amoebic keratitis patient associated with overnight-wear orthokeratology lens in Korea, we conducted mitochondrial DNA restriction fragment length polymorphism, 18S rDNA sequencing, and drug sensitivity analyses on the isolate (KA/PE1). The patient was treated with polyhexamethylene biguanide, chlorhexidine and oral itraconazole, which resulted in resolution of the patientos ocular inflammation. The majority of the molecular characteristics of the KA/PE1 were determined to be identical, or quite similar, to those of A. castellanii Ma strain, which had been isolated also from amoebic keratitis. The risk of Acanthamoeba keratitis as a potential complication of overnight orthokeratology is briefly discussed.
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Affiliation(s)
- Sun Joo Lee
- Department of Parasitology, School of Medicine, Pusan National University, Busan, Korea
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19
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Lee JK, Lee JE, Lee JS. A Case of Fungal Keratitis as a Complication of Orthokeratology Contact Lens. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2007. [DOI: 10.3341/jkos.2007.48.10.1415] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Ja Kyun Lee
- The Department of Ophthalmology, College of Medicine, Pusan National University, Pusan, Korea
| | - Ji Eun Lee
- The Department of Ophthalmology, College of Medicine, Pusan National University, Pusan, Korea
| | - Jong Soo Lee
- The Department of Ophthalmology, College of Medicine, Pusan National University, Pusan, Korea
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20
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Ikema K, Matsumoto K, Inomata Y, Komohara Y, Miyajima S, Takeya M, Tanihara H. Induction of matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs correlates with outcome of acute experimental pseudomonal keratitis. Exp Eye Res 2006; 83:1396-404. [PMID: 16968651 DOI: 10.1016/j.exer.2006.07.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2006] [Revised: 07/04/2006] [Accepted: 07/19/2006] [Indexed: 10/24/2022]
Abstract
This study aimed to investigate expressions and sources of matrix metalloproteinases (MMP)-2 and MMP-9, and of tissue inhibitors of MMP (TIMP)-1 and TIMP-2 in experimental Pseudomonas aeruginosa keratitis in rabbits. Pseudomonal keratitis was induced in New Zealand white rabbits, and macroscopic and microscopic examinations were performed at appropriate time points (3, 9, 12, 18, 24, 72 h). Expressions and sources of MMP-2, 9, and TIMP-1, 2 were determined using immunohistochemistry, gelatin zymography, ELISA, and RT-PCR. A typical corneal ulcer with a ring abscess was observed 12-72 h post-infection (p.i.) with P. aeruginosa. In microscopic examinations, massive inflammatory cell (mostly polymorphonuclear leukocytes, PMNs) infiltration and liquefactive necrosis were characteristic features. MMP-2 was constitutively expressed in keratocytes, and its expression was not apparently enhanced after pseudomonal infection as evidenced by zymography, immunostaining, and RT-PCR. However, MMP-9 and its activated form were induced, and were significantly enhanced 12-24 h p.i. MMP-9 appeared to derive from PMNs rather than from resident corneal cells. TIMP-1 was expressed in PMNs, macrophages, and keratocytes, and its expression was enhanced 72 h p.i. Although TIMP-2 was constitutively expressed as seen by immunostaining and RT-PCR, its concentration was below detection limits during the experiments. We demonstrated that MMP-9 was one of the important factors for corneal tissue destruction, because it was induced and significantly expressed in keratocytes and inflammatory cells after pseudomonal infection. Although TIMP-1 was expressed in later stages of infection, enhancement and activation of MMP-9 were much faster and stronger than those of TIMP-1, thereby facilitating tissue destruction leading to corneal ulceration.
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Affiliation(s)
- Kousuke Ikema
- Department of Ophthalmology and Visual Science, Kumamoto University Graduate School of Medical Sciences, Honjo, Kumamoto, Japan
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21
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Ng LHY. Central corneal epitheliopathy in a long-term, overnight orthokeratology lens wearer: a case report. Optom Vis Sci 2006; 83:709-14. [PMID: 17041315 DOI: 10.1097/01.opx.0000236813.39603.49] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
PURPOSE The purpose of this study is to report an unusual case of central corneal epitheliopathy (CCE) in a long-term orthokeratology lens wearer. CASE REPORT A single observational case report of a 12-year-old Chinese female myope with 3(1/2) years' experience in wearing orthokeratology lenses overnight was diagnosed with a CCE lesion during her regular orthokeratology aftercare consultation. The patient was asymptomatic. Trace or almost negative fluorescein staining was observed over the particular lesion area and, according to the clinical features of the corneal lesion, was thought to be a partially formed "dellen." The lesion healed after the use of the orthokeratology lenses was suspended for 4 months and reappeared when the patient resumed wearing the lenses. Close monitoring of the corneal condition was needed on this patient, and permanent discontinuation of the orthokeratology procedures will be considered if the signs and symptoms of the lesion worsen. DISCUSSION The etiology, clinical management and the possible differential diagnosis of the central cornea "dellen" are discussed. CONCLUSION A central corneal "dellen" may be associated with long-term, overnight use of orthokeratology lenses.
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Affiliation(s)
- Larry Hou-Yan Ng
- The Hong Kong Polytechnic University, School of Optometry, Hung Hom, Kowloon, Hong Kong, China
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22
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Sun X, Zhao H, Deng S, Zhang Y, Wang Z, Li R, Luo S, Jin X. Infectious keratitis related to orthokeratology. Ophthalmic Physiol Opt 2006; 26:133-6. [PMID: 16460313 DOI: 10.1111/j.1475-1313.2006.00381.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE To report 28 cases of infectious keratitis related to orthokeratology lens overnight wear in China. METHODS From March 2000 to August 2001, 28 cases of infectious keratitis related to overnight orthokeratology lens wear were diagnosed in Beijing Institute of Ophthalmology. These were retrospectively reviewed with regard to the pathogens isolated, duration of wear, the time since onset of symptoms, and age. Cultures of corneal scrapes for bacteria, fungus and Acanthamoeba were performed in all of the 28 cases. RESULTS All cases were students, including 10 males and 18 females, average age was 16 years (range 10-21 years). The duration of orthokeratology overnight wearing was from 2 weeks to 2 years. Uncorrected visual acuity (UCVA) on initial examination in our institute was from 20/200 to light perception. Of 28 isolates, 24 were culture positive (including 11 bacteria, 11 Acanthamoeba and two fungi), and four were culture negative. In two of the four culture negative cases, Acanthamoeba cysts were detected in the corneal stroma with the confocal microscope. Acanthamoeba and Pseudomonas aeruginosa accounted for 75% (21 of 28) of the cases of infectious keratitis. CONCLUSION Infectious keratitis is a severe complication associated with overnight orthokeratology lens wear. Ophthalmologists should pay more attention to this complication in practice.
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Affiliation(s)
- Xuguang Sun
- Department of Ocular Microbiology, Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital University of Medical Science, Beijing 100005, China.
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23
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Abstract
The use of multipurpose solutions for cleaning and disinfecting rigid gas permeable lenses has replaced single purpose solutions, but there are no reports of the efficacy of these multipurpose solutions, or of the effects of storage conditions on their disinfecting capacities. This study investigated activity against four bacterial and two fungal species, and the effects of storage in a refrigerator, at room temperature, at elevated temperature in both dry and humid conditions and with exposure to sunlight. The disinfecting solutions were challenged with the micro-organisms initially upon opening and then at 2-weekly intervals up to 12 weeks after being stored under the different conditions. Solutions were opened daily to simulate use. One solution failed to meet Food and Drug Administration (FDA) criteria to reduce numbers of bacteria by three log dilutions and of fungi by one log dilution. Storage reduced activity of all solutions over the 12-week period, but not below the requirements of the FDA. Storage in the refrigerator tended to reduce disinfecting capacity more quickly. Multipurpose solutions for rigid gas permeable (RGP) lenses lose activity over the 3 months recommended time of use but remain satisfactory for use over this time in the conditions tested. Practitioners need to remind patients to replace their solutions regularly and should advise against storage in the refrigerator. Multipurpose solutions for RGP lenses have simplified cleaning and disinfecting processes and the current formulations have improved disinfecting capacity compared to former disinfecting solutions, which is particularly important for wearers of orthokeratology lenses.
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Affiliation(s)
- Maureen Boost
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, China.
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24
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Mathews SM, Spallholz JE, Grimson MJ, Dubielzig RR, Gray T, Reid TW. Prevention of Bacterial Colonization of Contact Lenses With Covalently Attached Selenium and Effects on the Rabbit Cornea. Cornea 2006; 25:806-14. [PMID: 17068458 DOI: 10.1097/01.ico.0000224636.57062.90] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE Although silicone hydrogel materials have produced many corneal health benefits to patients wearing contact lenses, bacteria that cause acute red eye or corneal ulcers are still a concern. A coating that inhibits bacterial colonization while not adversely affecting the cornea should improve the safety of contact lens wear. A covalent selenium (Se) coating on contact lenses was evaluated for safety using rabbits and prevention of bacterial colonization of the contact lenses in vitro. METHODS Contact lenses coated with Se were worn on an extended-wear schedule for up to 2 months by 10 New Zealand White rabbits. Corneal health was evaluated with slit-lamp biomicroscopy, pachymetry, electron microscopy, and histology. Lenses worn by the rabbits were analyzed for protein and lipid deposits. In addition, the ability of Se to block bacterial colonization was tested in vitro by incubating lenses in a Pseudomonas aeruginosa broth followed by scanning electron microscopy of the contact lens surface. RESULTS The covalent Se coating decreased bacterial colonization in vitro while not adversely affecting the corneal health of rabbits in vivo. The Se coating produced no noticeable negative effects as observed with slit-lamp biomicroscopy, pachymetry, electron microscopy, and histology. The Se coating did not affect protein or lipid deposition on the contact lenses. CONCLUSION The data from this pilot study suggest that a Se coating on contact lenses might reduce acute red eye and bacterial ulceration because of an inhibition of bacterial colonization. In addition, our safety tests suggest that this positive effect can be produced without an adverse effect on corneal health.
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Affiliation(s)
- Steven M Mathews
- Department of Ophthalmology and Visual Sciences, Texas Tech University Health Science Center, Lubbock, TX 79430, USA.
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25
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Ying-Cheng L, Chao-Kung L, Ko-Hua C, Wen-Ming H. Daytime orthokeratology associated with infectious keratitis by multiple gram-negative bacilli: Burkholderia cepacia, Pseudomonas putida, and Pseudomonas aeruginosa. Eye Contact Lens 2006; 32:19-20. [PMID: 16415688 DOI: 10.1097/01.icl.0000167714.53847.8c] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE To report a case of a corneal ulcer in a patient who wore orthokeratology contact lenses during the day. METHODS Case report. RESULTS A 16-year-old girl who underwent orthokeratology treatment developed a corneal ulcer in her right eye. The refractive status of the affected eye was -5.75 -1.75 x 180, and the best-corrected visual acuity was 20/40. Corneal topography showed the temporal upper dislocation of a central flattened zone in the right eye. The patient had worn orthokeratology contact lenses during the day for more than 4 years. Her ulcer became worse after treatment with tobramycin and gentamicin for 1 day. After treatment with ciprofloxacin, the ulcer healed, and visual acuity returned to 20/20 with spectacle correction. Cultures of the cornea, contact lens, and lens solution all grew Burkholderia cepacia, Pseudomonas putida, and Pseudomonas aeruginosa. CONCLUSIONS Improper fitting of lenses and contamination of lenses or solutions in orthokeratology therapy are risk factors for a corneal ulcer, even when patients wear orthokeratology lenses only during the day.
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Affiliation(s)
- Lin Ying-Cheng
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan
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26
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Abstract
PURPOSE Despite growing evidence for clinical efficacy of orthokeratology (OK) for the temporary reduction of myopic refractive error, there has been an increasing number of reports of microbial keratitis (MK) in association with overnight wear of OK lenses. This article analyzes the first 50 cases of MK reported in overnight OK, in order to define the spectrum of the disease and to identify possible risk factors. METHODS All reported cases of presumed MK in overnight OK from 2001 onwards were included in the analysis. Demographic data of patients affected and lenses worn, and details of the disease process and possible risk factors were extracted from these reports. RESULTS Most cases of MK in OK were reported from East Asia (80%) and most affected patients were Asian (88%). The peak age range was from 9 to 15 years (61%). Although Pseudomonas aeruginosa was the predominant organism implicated in this series of cases (52%), an alarmingly high frequency of Acanthamoeba infection (30%) was found. Inappropriate lens care procedures, patient noncompliance with practitioner instructions, and persisting in lens wear despite discomfort emerged as potential risk factors. CONCLUSIONS The high frequency of MK in overnight OK in young Asian patients is likely to reflect the demographics of the OK lens-wearing population. The high frequency of Acanthamoeba infection strongly suggests that tap water rinsing should be eliminated from the lens care regimen for overnight OK. This study does not reveal the absolute incidence or relative risk of MK in overnight OK, and it is therefore premature to ascribe increased risk to this lens-wearing modality compared with other contact lens modalities.
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Affiliation(s)
- Kathleen Watt
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
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27
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Hsiao CH, Lin HC, Chen YF, Ma DHK, Yeh LK, Tan HY, Huang SCM, Lin KK. Infectious keratitis related to overnight orthokeratology. Cornea 2005; 24:783-8. [PMID: 16160492 DOI: 10.1097/01.ico.0000175412.13612.8a] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To report the microbial culture results, clinical course, and visual outcomes for infectious keratitis related to overnight orthokeratology. METHODS The records of patients with infectious keratitis related to overnight orthokeratology who presented to a tertiary referral center from April 2000 to March 2003 were retrospectively reviewed. RESULTS Twenty patients (21 eyes) were included; 1 patient had bilateral infections. The average age of the patients was 14 years. The average period between the time the patient started the overnight orthokeratology program and the onset of infectious keratitis was 23 months. Thirteen of the 21 eyes were culture positive. Organisms cultured were Pseudomonas aeruginosa (n = 9), coagulase-negative Staphylococcus species (n = 2), Serratia marcescens (n = 1), and Acathamoeba species (n = 1). All patients responded well to medical antimicrobial treatment. Final best spectacle-corrected visual acuity ranged from 20/20 to 20/100. CONCLUSIONS Infectious keratitis is a potential complication of overnight orthokeratology that may cause significant visual impairment. Parents of children who consider overnight orthokeratology should evaluate the benefit of temporary myopia reduction and the risk of infection.
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Affiliation(s)
- Ching-Hsi Hsiao
- Department of Ophthalmology, Chang Gung Memorial Hospital, No. 199, Tung Hwa North Road, Taipei, Taiwan, Republic of China
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28
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Abstract
PURPOSE This study was designed to report the clinical aspects, microbiologic findings, and treatment outcomes of overnight orthokeratology-associated microbial keratitis. METHODS Medical records of patients with overnight orthokeratology-associated microbial keratitis at National Taiwan University Hospital from August 2000 to October 2001were reviewed. The clinical and microbiologic characteristics and treatment outcomes were investigated. RESULTS Nine patients (in total 10 eyes) from aged 8 to 17 (mean, 12.3 +/- 2.9) years were included in this study. Eight patients had a unilateral infection and one had a bilateral infection. The initial best corrected visual acuities ranged from hand motion to 20/20. The lesions were located at the central cornea in nine eyes (90%). Smears and cultures from corneal scrapings were obtained from all patients. Four eyes were culture-positive, which included nonfermentative Gram-negative bacillus, Pseudomonas aeruginosa and Acanthamoeba. Positive smears from another two eyes revealed Gram-negative bacilli and double-walled cyst. All patients were cured using antimicrobial medications with complete re-epithelization and disappearance of corneal infiltrates. Four eyes had a final best corrected visual acuity of 20/30 or worse after a mean follow-up of 9.4 months, including one eye that had visual acuity of hand motion only. Complications included corneal opacity in all eyes, glaucoma in one eye, and cataract in one eye. CONCLUSIONS Overnight orthokeratology is an important risk factor of microbial keratitis, especially in school children. Acanthamoeba and Gram-negative bacilli, especially Pseudomonas aeruginosa, are the most common pathogens in our series. The risk of microbial keratitis after overnight orthokeratology should not be overlooked.
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Affiliation(s)
- Chia-Hui Tseng
- Department of Ophthalmology, National Taiwan University Hospital, National Taiwan University, Taipei, Taiwan
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29
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Abstract
PURPOSE To report an infectious complication of overnight rigid gas-permeable contact lenses. METHODS Case report and medical literature review. RESULTS A 16-year-old girl developed laboratory-confirmed acanthamoebic keratitis during orthokeratology for myopic reduction. Recent case reports suggest that Acanthamoeba is a cause of microbial keratitis associated with gas-permeable contact lenses among teenagers and young adults undergoing orthokeratology. CONCLUSIONS Acanthamoeba keratitis is an emerging complication of orthokeratology in young myopes.
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Affiliation(s)
- Kirk R Wilhelmus
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA.
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30
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Yepes N, Lee SB, Hill V, Ashenhurst M, Saunders PPR, Slomovic AR. Infectious Keratitis After Overnight Orthokeratology in Canada. Cornea 2005; 24:857-60. [PMID: 16160504 DOI: 10.1097/01.ico.0000154388.43501.f8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To report 3 cases of infectious keratitis related to overnight orthokeratology use. METHODS Retrospective case observation. RESULTS All 3 patients were using overnight orthokeratology lenses when they presented with unilateral corneal ulcers. The organisms isolated were Acanthamoeba, Pseudomonas aeruginosa, and Serratia marcescens. The clinical presentation and treatment of each case is presented. CONCLUSIONS Overnight orthokeratology use may be associated with infectious keratitis despite the use of more oxygen-permeable materials and improved lens design. Patient education with informed consent, appropriate lens care, and meticulous follow-up is important. Because this complication is potentially sight threatening, orthokeratology requires further analysis and evaluation to establish its safety. The cases here are the first few reported cases in North America.
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Affiliation(s)
- Natasha Yepes
- Department of Ophthalmology and Vision Science, University of Toronto, Toronto Western Hospital, Toronto, Ontario, Canada
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31
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Araki-Sasaki K, Nishi I, Yonemura N, Takatsuka H, Mutoh K, Matsumoto K, Asari S, Tanihara H. Characteristics of Pseudomonas corneal infection related to orthokeratology. Cornea 2005; 24:861-3. [PMID: 16160505 DOI: 10.1097/01.ico.0000175411.05988.fa] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE To describe a Pseudomonas aeruginosa corneal infection resulting from orthokeratology. METHODS Case report. RESULTS A 17-year-old boy wearing orthokeratology (OK) lenses was referred to our clinic because of redness in his right eye in spite of his usage of ofloxacin (OFLX) eye drops. An excavated paracentral corneal ulcer with an immune ring and hypopyon was observed. It was positioned under the paracentral steeper portion of the optic of the OK lens. Culture of the lens solution revealed P. aeruginosa. The patient was treated with topical OFLX and cefmenoxime (CMX) plus intravenous and subconjunctival injections of cefozopran (CZOP), successfully. The antibiotic susceptibility of P. aeruginosa by the disk diffusion susceptibility test was reduced under moderately hypoxic conditions. Glycocalyx slime was formed on the OK lens in vitro by P. aeruginosa isolated from the case. CONCLUSIONS Changes in P. aeruginosa susceptibility to antibiotics under moderately hypoxic conditions and glycocalyx slime formation might affect the features of OK lens-associated infections.
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32
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Boost MV, Cho P. Microbial flora of tears of orthokeratology patients, and microbial contamination of contact lenses and contact lens accessories. Optom Vis Sci 2005; 82:451-8. [PMID: 15976581 DOI: 10.1097/01.opx.0000168587.72893.ec] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
PURPOSE The purpose of this study is to determine if there are changes in the ocular flora of overnight orthokeratology (ortho-k) patients, and the levels of contamination of their lenses and lens accessories, and to correlate compliance with levels of contamination. METHOD Normal ocular flora of 41 subjects was determined twice before commencing ortho-k lens wear by culture of the lower conjunctiva. Further specimens were collected on six follow-up visits after beginning lens wear, as were samples from their lenses, cases, and suction holders. A questionnaire on lens care was administered after the fifth visit. RESULTS Three subjects provided conjunctival samples yielding Staphylococcus aureus on one occasion before lens wear, one being positive for this organism after beginning lens wear. Of 38 subjects yielding no growth or only normal eye flora before use, 28 remained free of ocular pathogens after beginning lens wear. Only four subjects had positive cultures on more than one occasion after lens wear. There was no significant difference in isolation levels of pathogens with lens wear (p = 0.423). Lens culture of 54% of subjects yielded no growth or normal flora only; lenses of 16 subjects yielded potential pathogens, including three subjects contaminated on more than one occasion. Lens isolates did not match the organisms transiently colonizing the eye. Lens case, the most frequently contaminated item, was associated with lens contamination (p < 0.001), the same organism being isolated from both items in 11 subjects. Lens suction holder was less frequently contaminated. Neither lens case nor suction holder contamination was associated with isolates from the eye. Reported good compliance correlated with lack of contamination in all but one subject. The most frequent breaches in the lens care protocol were failure to clean, disinfect, and replace the lens case. CONCLUSION Ocular flora was not altered by ortho-k lens wear over an extended period, and patients remained free of infection. Contaminants identified were generally of a transient nature. Most patients had significant contamination of at least one item, most frequently the lens case. Lens case isolates were significantly associated with those from the lens. The majority of patients reporting good compliance had low or no contamination of their lenses and accessories.
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Affiliation(s)
- Maureen V Boost
- Centre for Myopia Research, Department of Optometry & Radiography, The Hong Kong Polytechnic University, Hong Kong Special Administrative Region, China
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33
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Walline JJ, Holden BA, Bullimore MA, Rah MJ, Asbell PA, Barr JT, Caroline PJ, Cavanagh HD, Despotidis N, Desmond F, Koffler BH, Reeder K, Swarbrick HA, Wohl LG. The Current State of Corneal Reshaping. Eye Contact Lens 2005; 31:209-14. [PMID: 16163012 DOI: 10.1097/01.icl.0000179709.76832.4f] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE The application of contact lenses to alter the shape of the cornea and temporarily reduce or eliminate myopia is known as orthokeratology, corneal refractive therapy, or corneal reshaping. It was first introduced in the 1960s, but high oxygen permeable materials and more sophisticated designs allow patients to wear contact lenses only during sleep, while dramatically improving the predictability and rate of myopia reduction. Many studies have shown that most corneal reshaping patients achieve uncorrected visual acuity of 20/25 or better that lasts all day long in one to two weeks of nighttime wear. Treatment is primarily effective through central epithelial thinning and midperipheral epithelial and stromal thickening. Much remains to be learned about corneal reshaping contact lenses and their effects on the cornea. METHODS The authors reviewed existing knowledge and determined what needs to be learned in order to provide patients with appropriate informed consent prior to corneal reshaping contact lens wear. RESULTS While corneal reshaping contact lenses are effective at temporarily reducing or eliminating myopia, claims about the progress of myopia being controlled with corneal reshaping contact lenses should not be made until further studies are published in peer-reviewed literature. The incidence and prevalence of microbial keratitis related to corneal reshaping contact lens wear is not known. Any overnight wear of contact lenses increases the risk of infection, but it is not known whether the risks of microbial keratitis are greater for corneal reshaping overnight contact lens wearers than other form of overnight contact lens wear. It is also not known whether the risk of microbial keratitis is greater for children than adults, but we must determine if children are at greater risk than adults because many children are wearing corneal reshaping contact lenses. CONCLUSIONS Finally, it is recommended that ongoing education be provided to practitioners and staff regarding safety, informed consent, and prevention of potential problems, with special emphasis on the critical need to properly and thoroughly disinfect lenses that will be worn overnight.
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Affiliation(s)
- Jeffrey J Walline
- The Ohio State University College of Optometry, The Vision Cooperative Research Centre, OH, USA
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Shin YJ, Kim MK, Wee WR, Lee JH, Shin DB, Lee JL, Xu YG, Choi SW. Change of Proliferation Rate of Corneal Epithelium in the Rabbit with Orthokeratology Lens. Ophthalmic Res 2005; 37:94-103. [PMID: 15746565 DOI: 10.1159/000084251] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2004] [Accepted: 10/20/2004] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To investigate the cell proliferation rate of normal corneal epithelium with extended orthokeratology lens (OKL) wear in comparison with extended rigid gas-permeable (RGP) lens wear. METHODS Twenty-four rabbits were fitted unilaterally with either an OKL or an RGP lens, and the other eye was used as a control. They were injected with 5-bromo-2-deoxyuridine (BrdU) 24 h prior to being sacrificed. The rabbits were sacrificed at 1, 3, 7 and 14 days after lens fitting. The cornea from the superior limbus to the center was taken at 1.0-mm intervals. The BrdU-labeled cells were counted in medium power fields (x200) in each sample using light microscopy. RESULTS The number of BrdU-labeled cells in the RGP lens group initially increased, but the number decreased in the corneal center and superior limbus by 32 and 8%, respectively, after 14 days. There was no statistically significant change. However, the number of BrdU-labeled cells in the OKL group decreased after 3 days, and the number of BrdU-labeled cells was reduced in the center and superior limbus by 63 and 8%, respectively, after 14 days. The change in proliferation in the corneal center in the OKL-wearing rabbits was statistically significant compared to the control (p < 0.05). CONCLUSIONS Wearing an OKL had a greater effect on the change of the proliferation pattern in the epithelium than wearing an RGP lens, which suggests that the OKL might be less physiologic than the RGP lens is.
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Affiliation(s)
- Young Joo Shin
- Department of Ophthalmology, Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, Seoul 110-744, Korea
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Ladage PM, Yamamoto N, Robertson DM, Jester JV, Petroll WM, Cavanagh HD. Pseudomonas aeruginosa corneal binding after 24-hour orthokeratology lens wear. Eye Contact Lens 2004; 30:173-8. [PMID: 15499241 DOI: 10.1097/01.icl.0000133220.32701.c8] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE To examine the effect of short-term 24-hr orthokeratology lens (OKL) wear on Pseudomonas aeruginosa binding, epithelial surface cell morphology, epithelial sheet thickness, and stromal thickness in a rabbit model. METHODS Seventeen New Zealand white rabbits were treated according to the Association for Research in Vision and Ophthalmology Statement for the Use of Animals in Ophthalmic and Vision Research. Partial membranectomy was performed on all rabbits 1 week before the experiments. Baseline values for epithelial and stromal thickness and epithelial surface cell size were determined by in vivo confocal microscopy in one randomly chosen eye (n = 6). One week later, rabbits were fitted in the same eye with a hyper oxygen-transmissible OKL. Twenty-four hours later, confocal microscopy was repeated. The second group of rabbits (n = 6) was fitted with an OKL in one randomly chosen eye for 24 hr. P. aeruginosa binding to the corneal epithelium was assessed for the control corneas and those exposed to the test lens. Scanning electron microscopy was performed on a third group of rabbits to assess epithelial surface damage (n = 5). RESULTS There was a statistically significant difference (P<0.001) in P. aeruginosa binding between the control (1.11 +/- 0.74 x 10(5) colony-forming units per cornea) and the OKL-wearing eyes (2.74 +/- 0.69 x 10(5) colony-forming units per cornea). The central epithelium thinned by 6.5% after lens wear (48.2 +/- 1.9 microm to 45 +/- 1.7 microm, P=0.005); however, central stromal thickness increased by 7.3% (322 +/- 22 microm to 345 +/- 29 microm, P=0.006). Compared with the baseline value, central epithelial cell size increased significantly from 1,253 +/- 140 mm(2) to 1,627 +/- 393 mm(2) (29.4%, P=0.02). Scanning electron microscopy showed increased surface epithelial damage associated with OKL wear. CONCLUSIONS This prospective, masked, pilot study showed that 24-hr hyper oxygen-transmissible OKL wear induced a statistically significant increase in P. aeruginosa binding to the epithelium of the rabbit cornea, accompanied by central epithelial thinning, stromal thickening, and surface cell damage assessed by scanning electron microscopy. Collectively, the data suggest that despite adequate lens oxygen transmissibility, the mechanical pressure inherent in the OKL design exerted on the corneal surface appears to be associated with increased adherence of P. aeruginosa to surface corneal epithelial cells, which may pose an increased risk for lens-related microbial keratitis, especially in overnight (i.e., closed-eye) wearing conditions. Future studies are needed to determine whether these results are similar in human wear and how P. aeruginosa binding during OKL wear compares with other lens-wearing modalities, such as daily or continuous soft lens wear.
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Affiliation(s)
- Patrick M Ladage
- Department of Ophthalmology, University of Texas, Southwestern Medical Center at Dallas, Dallas, TX 75390-9057, USA
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Abstract
PURPOSE This case series presents the first documented cases of infectious ulcers associated with overnight orthokeratology in North America and other less serious complications associated with overnight corneal reshaping. CASE REPORTS Five cases of adverse corneal events associated with corneal refractive therapy are described: two cases of microbial keratitis, one case of infiltrates, one case of toxic keratitis, and one corneal abrasion. CONCLUSIONS Corneal compromise and poor compliance can cause adverse events with corneal reshaping. The need for ongoing patient education is important not only for pediatric contact lens patients, but also for adults.
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Affiliation(s)
- Jacob Lang
- New England College of Optometry, Boston, MA, USA
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Choy CKM, Cho P, Benzie IFF, Ng V. Effect of One Overnight Wear of Orthokeratology Lenses on Tear Composition. Optom Vis Sci 2004; 81:414-20. [PMID: 15201714 DOI: 10.1097/01.opx.0000135094.15125.4c] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
PURPOSE To evaluate the effect of one night of orthokeratology lens wear on ocular surface health based on the changes in tear components, including ascorbate, urate, lactate dehydrogenase (LD), lactoferrin, lipocalin, lysozyme, secretory immunoglobulin A (sIgA), and serum albumin. METHODS Changes in tear components in eight healthy young men before and after 7-h overnight ortho-k lens wear were studied. Subjects attended on two separate occasions during a 1-week period, on one occasion wearing lens overnight and on the other wearing no lens. Tears (yawn-induced) were collected by capillary tube before lens fitting and on awakening. Tear ascorbate and urate were measured by high-performance liquid chromatography; LD was measured by a commercial kit method; tear proteins were measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. RESULTS Ascorbate, sIgA, albumin, and LD increased significantly overnight with and without overnight lens wear (p < 0.05); however, no significant increases were found in tear urate, lactoferrin, lipocalin, or lysozyme (p > 0.05). Without lens wear, tear ascorbate, sIgA, albumin, and LD increased by 21%, 34%, 9-fold, and 13-fold, respectively (p < 0.05). With ortho-k lens wear, significant flattening of the apical curvature was observed as expected, and the increases in tear ascorbate, sIgA, albumin, and LD (increases were 56%, 76%, 13-fold, and 14-fold, respectively) were significantly (p < 0.05) greater than with no lens. There was significant correlation seen between changes in albumin and LD with (r = 0.762; p = 0.037) and without (r = 0.738; p = 0.046) ortho-k lens wear. CONCLUSIONS The result of tear ascorbate suggests that corneal cell disturbance is small after one night of ortho-k lens wear. The marked increases in albumin and LD suggest that the ocular surface is under additional hypoxic stress during overnight ortho-k lens wear.
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Affiliation(s)
- Camus Kar Man Choy
- Department of Optometry and Radiography and School of Nursing, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China.
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