Ortho Keratology (ortho is "straight" in Greek, Kera is "Cornea" in Greek, and "ology" is the "science of" or the study of) is a method whereby a gas permeable contact lens is used by the patient, usually while sleeping, to reshape the cornea to decrease myopia (most often) and astigmatism.
It does decrease the progression of myopia in most studies. A very good study by an eyeMD at Harvard is below.
It does have risks.
[10]
[11]
[12]
[13]
It does decrease the progression of myopia in most studies. A very good study by an eyeMD at Harvard is below.
It does have risks.
It does work but has some serious risks:
1. Corneal infection/ulcer leading to possible permanent loss of best corrected vision:
Here are how many have been published to date.
The Harvard Study below notes:
Here are how many have been published to date.
The Harvard Study below notes:
173 eyes Systematic Review Hong Kong 2017
1 Mooren Ulcer 2018
6 in China 2004
2 in Taiwan 2003
A long term risk that has not been adequately studied is the risk of long term meibomian gland disease and chronic dry eye.
Before getting Ortho K for yourself or your child, be sure to get a meibography to see if there are enough oil glands. If not, Ortho K is not a good option as chronic contact lens use can worsen MGD and dry eye symptoms.
SLC
References:
Before getting Ortho K for yourself or your child, be sure to get a meibography to see if there are enough oil glands. If not, Ortho K is not a good option as chronic contact lens use can worsen MGD and dry eye symptoms.
SLC
References:
Infectious keratitis and orthokeratology lens use: a systematic review.
Review article
Kam KW, et al. Infection. 2017.
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.
Mooren Ulcer in a Child Wearing Orthokeratology Contact Lenses.
Kim J, et al. Eye Contact Lens. 2018.
Abstract
PURPOSE: To report a case of Mooren ulcer that developed in a pediatric patient wearing orthokeratology overnight contact lenses.
METHODS: Case report.
RESULTS: A 10-year-old boy was referred to our clinic because of progressive peripheral corneal ulcer in the right eye, despite the intensive use of fortified antibiotic eye drops. The patient had been using overnight orthokeratology lenses for 4 months before presentation of corneal ulcer. There was no other history of ocular or systemic trauma and disorders. Microbiological tests of the lesion were negative. Systemic evaluation showed no sign of rheumatologic disease. Under a diagnosis of Mooren ulcer, the patient was treated with topical and systemic corticosteroids. After four weeks of treatment, the patient's symptoms rapidly disappeared, and corneal ulcer was healed. The vision recovered to normal with the correction of with-the-rule astigmatism.
CONCLUSIONS: Mooren ulcer can develop in pediatric patients wearing orthokeratology contact lenses. Given rapid progression of Mooren ulcer in a young population, early diagnosis and proper treatment are essential to prevent a devastating outcome
Orthokeratology lens-related corneal ulcers in children: a case series.
Young AL, et al. Ophthalmology. 2004.
Abstract
OBJECTIVE: Orthokeratology is a process by which the corneal curvature is flattened by sequentially fitting rigid gas permeable contact lenses of decreasing central curvature. There has been a resurgence of interest with the recent introduction of reverse geometry lenses. Although promising results have been described in reducing the myopic refractive error, the use of these lenses can be associated with corneal problems, as reported in this case series.
DESIGN: Observational case series.
PARTICIPANTS: Six children with orthokeratology-related corneal ulcers.
METHODS: Consecutive cases of orthokeratology lens (OKL)-related corneal ulcers in children presented to a tertiary referral center (March 1999-June 2001) were reviewed.
MAIN OUTCOME MEASURES: Preinfection and postinfection visual acuity, refraction, any organisms identified.
RESULTS: Six children between the ages of 9 and 14 years (mean = 12.1) were treated. The male:female ratio was 1:5. All cases were unilateral, with equal numbers of left and right eyes. All children wore the OKL at night for a duration of 8 to 12 hours, with the onset of infection between 3 and 36 months (mean = 16.6) of OKL wear. All of the patients suffered a resultant best-corrected visual acuity loss. Five of the 6 cases were culture positive for Pseudomonas aeruginosa.
CONCLUSIONS: In view of the temporary benefits of orthokeratology, together with a known increased risk of infection associated with overnight lens wear, parents of children considering orthokeratology must be informed and warned of the potential for permanent loss of vision. The ophthalmic community should have a heightened awareness of the associated complications.
Pseudomonas corneal ulcer related to overnight orthokeratology.
Lau LI, et al. Cornea. 2003.
Abstract
PURPOSE: To report two cases of Pseudomonas aeruginosa corneal ulcers as a complication of overnight orthokeratology lens wear.
METHODS: Case report.
RESULTS: Two 11-year-old girls with acute central corneal ulcers were referred to our hospital. In both cases, the ulcers were about 2 mm in diameter, located centrally, contained dense cellular infiltration, and discharged purulent material. Intensive topical ceftazidime was applied to treat the ulcers. Cultures of the scraped corneal tissues and the contact lens storage solutions in both cases grew P. aeruginosa, which was sensitive to the antibiotic. The presenting best-corrected visual acuity was hand motion at 20 cm in one patient and 6/20 in the other. Both patients had received several months of overnight orthokeratology treatment with rigid gas permeable contact lenses to correct myopia (-4.25 D and -4.75 D in the two affected eyes). The final best-corrected visual acuity was 6/60 in one patient and 6/7.5 in the other.
CONCLUSIONS: Overnight orthokeratology contact lens wear carries a potential risk of corneal ulcer and may cause significant visual impairment in children.
Ophthalmic Technology Assessment
Use of Orthokeratology for the Prevention of Myopic Progression in Children: A Report by the American Academy of Ophthalmology
Received 20 November 2018, Revised 20 November 2018, Accepted 20 November 2018, Available online 23 November 2018.
Ophthalmic Technology Assessment
Use of Orthokeratology for the Prevention of Myopic Progression in Children: A Report by the American Academy of Ophthalmology
Received 20 November 2018, Revised 20 November 2018, Accepted 20 November 2018, Available online 23 November 2018.
Manuscript no. 2018-2613.
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Risk of Chronic Dry Eye and Meibomian Gland Dysfunction from Chronic Contact Lens Use:
Eye Contact Lens. 2018 Dec 28. doi: 10.1097/ICL.0000000000000572. [Epub ahead of print]
The Role of Soft Contact Lens Wear on Meibomian Gland Morphology and Function.
Abstract
PURPOSE:
To evaluate the impact of soft contact lens (CL) wear on the morphology and function of the meibomian glands (MG).
METHODS:
One hundred seventy-three eyes of 87 soft CL wearers and 103 eyes of 55 age-matched healthy volunteers were included into this study. The patients were divided into 3 groups according to the total duration of lens wear: less than 3 years, 3 to 7 years, and more than 7 years. Ocular Surface Disease Index (OSDI) scores, slitlamp biomicroscopy findings, fluorescein staining of the ocular surface, tear film break-up time (BUT), Schirmer I test, and meibography findings were recorded in all patient eyes and were compared with controls.
RESULTS:
The mean meiboscores of the upper and lower eyelids were significantly higher in CL wearers compared with controls (P<0.05). The mean BUT and the mean MG expressibility were significantly lower, whereas the mean OSDI score, corneal staining scores, percentage of partial/complete gland loss, and percentage of thickened and curled MG in upper/lower lids were statistically significantly higher in CL wearers (P<0.05). Meiboscores were significantly higher in patients with a total lens wear duration of more than 3 years compared to those with less than 3 years of lens wear for both upper/lower lids (P<0.05). The earliest morphological change in the MG of CL wearers was MG thickening, and this parameter was the only meibography finding that had the highest diagnostic ability for MG dysfunction.
CONCLUSION:
Soft CL wear causes significant morphological and functional changes in MG with thickening of MG presenting an early diagnostic finding of MG dysfunction on meibography.
M. Guillon, C. MaissaBulbar conjunctival staining in contact lens wearers and non lens wearers and its association with symptomatology
Cont Lens Anterior Eye, 28 (2) (2005), pp. 67-73
B.L. Ong, J.R. LarkeMeibomian gland dysfunction: some clinical, biochemical and physical observations
Ophthalmic Physiol Opt, 10 (2) (1990), pp. 144-148
A. Machalinska, A. Zakrzewska, B. Adamek, K. Safranow, B. Wiszniewska, M. Parafiniuk, et al.Comparison of morphological and functional Meibomian gland characteristics between daily contact lens wearers and nonwearers
Cornea, 34 (9) (2015), pp. 1098-1104
R. Arita, K. Itoh, K. Inoue, A. Kuchiba, T. Yamaguchi, S. AmanoContact lens wear is associated with decrease of meibomian glands
Ophthalmology, 116 (3) (2009), pp. 379-384
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Notes
Nice piece by Edric Wei, OD:
Generally speaking, an orthok lenses should be replaced annually to prevent any serious ocular complication.
What will happen to the orthok lenses over years?
As the lenses aged, protein deposits may build up and lens surface scratches may develop, both of which may affect the integrity of the lens and affects lens wearing experience.
As we know, proteins are complex organic compounds that exist throughout our body. In our tear, the main protein component is known as lysozyme which functions to combat microbial activities on the surface of the eye. As you keep wearing your lenses, lysozyme will denature (a chemical and physical transformation that causes a change in the configuration of the protein) due to oxidation and drying. The denatured lysozyme can build up on the surface of contact lenses forming protein deposits. Thus, reduced its' transparency and integrity and may also challenge the body's immune system causing inflammation, irritation, redness and itching.
Some of the serious ocular reactions known related to protein deposits are giant papillary conjunctivitis (GPC) and superior limbic keratoconjunctivitis (SPK), while keratitis is another immune response that experts have linked to denatured protein deposits.
Giant Pupillary Conjunctivitis (GPC)
Superior Limbic Keratoconjunctivitis (SPK)
Besides that, lens surface scratches may also develop while you are washing your lenses and during storage. Those scratches may increase the chances of protein deposit to stick on the lens surface.
Scratches seen on rigid gas permeable lenses.
Personally, I do advise my patient to replace the lenses annually and even stated the condition in the consent form. However, if the patient is really taking good care of their lenses I will somehow allow them to stick with it for up to 2 years provided they attend all the necessary follow-ups, no excessive protein deposits and lenses surface scratches are seen.
Edric Wei, OD
FDA accepts IND application to begin Eyenovia myopia study
Eyenovia announced the FDA accepted an investigational new drug application to initiate a phase 3 registration trial of MicroPine to reduce the progression of myopia in children.
According to a company press release, the U.S.-based, multicenter, randomized, double-masked CHAPERONE study will include 400 children between 5 and 12 years old. Participants will be randomly assigned to receive one of two MicroPine treatment concentrations or a placebo.
“The American Academy of Ophthalmology recently cited Level 1 evidence that topical lower doses of atropine treatment have demonstrated robust and sustained effect in slowing progressive myopia by up to 60% to 70%,” Sean Ianchulev, MD, MPH, Eyenovia’s CEO and chief medical officer, said in the release. “We believe that by combining the knowledge gained from these studies with our OpteJet, high-precision piezo-print microdose technology, we have the opportunity to potentially change the odds of progressive myopia.”
Trial enrollment is expected to begin in the first half of this year.
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