Packaging & Delivery

Topographic Map before Wearing MCT Lens

Topographic Map after Wearing MCT Lens

 

Case No. 2:

Patient´s Problem: Myopia with Astigmatism 

Topographic Map after Wearing MCT Lens

Dynamic analysis the changes of ocular axial length of different types of myopia.

WU gang-yue HUANG tang-qin.Jinhua Eye Hospital, Jinhua 321000

ABSTRACT 

Objective Dynamic analysis the changes of ocular axial length of different types of myopia(low Myopia group and moderate myopia group, low age group and high age group) after orthokeratology.

Methods Select 63 adolescents of wearing MCT Tech Design ortho-k lens in our hospital from 2009 to 2012,male 28, female 35, a total of 121 eyes, ranging in age from 8 to 14 years old,diopter degree≤ -6.00D, with-the-rule astigmatism≤ -1.50D, against-the-rule astigmatism≤-0.75D. To observe the changes of ocular axis after 1 week, 1 month, 3 months, 6 months, 12 months, 18 months, 24 months of wearing Ortho-K contact lens through overnight wear. The volunteers were divided into 4 groups: low myopia group ( the Diopter degree≤ -3.00 D ) and moderate myopia group (-3.00D ~ -6.00 D ); low age group ( 8 to 10 years old ) and aged group( 11~ 14 years old ). This grouping was according to the degree of myopia and age.

Results The growth of ocular axis after six months of wearing Ortho-K was statistically significant compared with unwearing ( t=4.68, P<0.05 ). The difference between ocular axial growth of the Moderate myopia group and the low myopia group after wearing a month later was statistically significant ( t=3.4, P<0.05 ), the axial growth of Moderate myopia group was slow, the axial growth between the low age group and the high age group had no significant difference(P>0.05).

ConclusionsThe effect of wearing MCT Tech ortho-k contact lens of controlling myopia is better for Moderate myopia than low myopia, while the factor of age has no effect on controlling myopia.

  [Key words]   Orthokeratology ; myopia control ; axial length  

Along with the increasing incidence of juvenile myopia, and the appearance in younger ages, more and ophthalmologists select effective way to control myopia. Orthokeratology is accepted by ophthalmologist in both domestic and abroad, but we clinically found that for ortho-k lens, its effect is uneven for different patients. For some wearers, their eye axis changes is little for a year or two years later, but for some wears, after a few months later, the axial became significantly longer and whether there is any objective factors, such as age, diopter, and so on? Now, we will show the treatment effect and the axis reports from our hospital for 3 years.

SUBJECTS & METHODS

1.Clinical Data

Selected from 63 cases teenagers who firstly wear Ortho-k lenses for over 2 years in 2009 to 2012. There are totally 121 eyes and male 28 cases and female 35 cases. The first wearing is from 8 ~ 14 years old, and the average age is 10.77 ± 1.90. The diopter of spherical power is - 6.00 D or less, the inverse rule astigmatism is - 1.50 DC, and the rule astigmatism is - 0.75 DC or less.

According to the degree of myopia, the wearers were divided into low myopia group whose spherical power was - 3.00 D or less and there were totally 68 eyes;

Moderate myopia group whose spherical power was 3.00 D ~ 6.00 D, and there were totally 53

According to the first wearing age, there was young age group 8-10 years old which had totally 62 eyes;

And older age group which is in 11 ~ 14 years old and totally 59 eyes.

2.Methods

(1) According to the standard fitting process of Ortho-k lens, all cases include the naked eye eyesight test, medical optometry correction, corneal topography curvature test, IOL Master, corneal thickness test, eye disease screening programme, such as slit lamp examination, non-contact intraocular pressure, retinal examination. (2) After excluding all contraindications, customized the lens according to the results of the corneal topographic map and the result of medical optometry. (3) Guide patients to wear and maintain lens, and ask patients strictly under the wearing time: wear 8 ~ 10 hours at night. Discuss with parents to and pay special attention to the clean and health. After wearing lens 1 day, 1 week, 1 month, 3 months, 6 months, 12 months, 18 months and 24 months, to do the recheck. The contents are the eyesight, eye axis, corneal topographic map, diopter, corneal thickness, intraocular pressure; Palpebral conjunctiva and bulbar conjunctiva, cornea transparency, damage, and phenomenons such as tears. If you feel unwell or have any abnormal, do the timely treatment, and stop wearing for a few days which are determined by the physician.

3. Materials & Equipment

The material of the lens is the third generation of Ortho-k lens, Boston XO whose DK value is 100. The lens is provided by E&E company in the United States; the lens is use reverse geometric four arcs design, and it total diameter is 9.80 ~ 11.60 mm. The lens is designed by Professor Wang in Shanghai Furen ophthalmic hospital. This lens is Ortho-k Leans designed by new digital model technology, and we also call it MCT lens. The lens greatly improved the traditional Orthokeratology, mainly used corneal shape, and make the cornea gradually to a more rational deformation, and finally help us to achieve the effect of safe vision correction, MCT lens, MCT technology provided by Wuhan Web Science and Technology Development Co., LTD and the measurement of eye axis is by IOL-master optical measurement instrument from Chua's Company.

4. Statistical Methods

Use SPSS19.0 test statistical software to do statistical analysis, and put P < 0.05 as difference. And then, there is statistical significance.