Effects of IOP Lowering Agents on Myopic Regression after Refractive

Surgery

Lim, Taehyung M.D., Hong, So Jin M.D., Cho, Beom Jin M.D., Ph.D.

Chung Kyu-Hyung M.D, Ph.D, Choi Kee-Yong M.D, Ph.D.

HanGil Eye Hospital

* All authors have no financial interest in the subject matter of this poster.

BackgroundBackground

The higher IOP, the more anterior shifting of the cornea

Factors affecting the forward shift of posterior corneal surface after laser in situ keratomileusis. Baek T, et al, 108(2):317-20, 2001, Ophthalmology

Factors affecting the forward shift of posterior corneal surface after laser in situ keratomileusis. Baek T, et al, 108(2):317-20, 2001, Ophthalmology

Differences between regressive eyes and non-regressive eyes after LASIK for myopia in the time course of corneal changes assessed with the Orbscan. Pan, et al, 218(2):96-101, 2004, Ophthalmologica

Differences between regressive eyes and non-regressive eyes after LASIK for myopia in the time course of corneal changes assessed with the Orbscan. Pan, et al, 218(2):96-101, 2004, Ophthalmologica

Regressive eye vs. Non-regressive eye differed in the corneal shifting movements after LASIK

Regression-related factors before and after laser in situ keratomileusis. Qi H. et al, 220(4):272-6,2006 Ophthalmologica

Regression-related factors before and after laser in situ keratomileusis. Qi H. et al, 220(4):272-6,2006 Ophthalmologica

IOP lowering may prevent myopic regression.

Evidences of correlation between IOP and refractive error after LASIK

BackgroundBackground

Effects of antiglaucoma drugs on refractive outcomes in eyes with myopic regression after laser in situ keratomileusis.

Kamiya K, et al, 145(2):233-238, Am J Ophthalmol, 2008

Effects of antiglaucoma drugs on refractive outcomes in eyes with myopic regression after laser in situ keratomileusis.

Kamiya K, et al, 145(2):233-238, Am J Ophthalmol, 2008

27 eyes with myopic regression after LASIKMean regression : 1.26±0.48D(-0.5 ~ -2.25D)2.5 % Nipradilol bid for 3months

Pretreatment 3 Months

Spherical -1.02±0.52D -0.44±0.39D*

Astigmatism -0.55±0.30D -0.49±0.22D

IOP 11.4±2.4mmHg 9.1±8.2mmHg*

CCT 505.2±39.3um 505.6±38.7um

15% of patients did not respond to the treatment.

Evidences of correlation between IOP and refractive error after LASIK

BackgroundBackground

Pretreatment 3 Months

Mean refractive power of the total cornea

(3mm)38.4±2.0D 37.7±2.0D

Posterior corneal surface shifted posteriorly by 9.1±8.2um (mean)

It is suggested that backward movement of the cornea may occur, possibly flattening the corneal curvature by lowering the IOP

Effects of antiglaucoma drugs on refractive outcomes in eyes with myopic regression after laser in situ keratomileusis.

Kamiya K, et al, 145(2):233-238, Am J Ophthalmol, 2008

Effects of antiglaucoma drugs on refractive outcomes in eyes with myopic regression after laser in situ keratomileusis.

Kamiya K, et al, 145(2):233-238, Am J Ophthalmol, 2008

Evidences of correlation between IOP and refractive error after LASIK

PurposePurpose

To evaluate effects of IOP lowering agents on patients who

have myopic regression after laser vision correction(LVC)

MethodsMethods

94 eyes in 47 patients (Male = 11 , Female = 36)

Mean age : 33.7 years (22~53)

Patients who have myopic regression after LVC

Occurrence of Myopic regression after LVC : postoperative 4y5m ± 3y11m (1month ~ 12 years)

Op PRK LASIK LASEK

Number 9 65 20

MethodsMethods

At the time of diagnosis, treatment was started with topical 0.5% timolol + 5% dorsolamide combination (Cosopt®, MSD, USA),twice daily for 3 months.

Outcome parameters :UCVA, BCVA, IOP, CCT, MR, Topography and ACD

f/u period : 1 week, 1 month, 3 months

ResultsResultsPre-

treatmentPost-treatment

1 month Post-treatment

3 months

Spherical error (D)*

-1.02±1.55 -0.50±1.27 -0.41±0.92

Astigmatism (D) -0.23±0.78 -0.18±0.77 -0.18±0.67

IOP(mmHg)* 10.55±5.75 9.17±3.69 9.64±3.78

CCT(um) 486.9±95.1 486.9±95.1 481.6±109.1

ACD(um) 3.23±0.50 3.29±0.61 3.27±0.58

Keratometry(D)†

AnteriorPosterior

39.61±3.77-6.43±0.64

38.36±3.94-6.36±0.51

39.43±3.36-6.41±0.55

* p < 0.05, paired T test for pre-treatment & Post-treatment 3 months† p < 0.05, paired T test for pre-treatment & Post-treatment 1 month

ResultsResults

* Refractive improvement : manifest refraction error (spherical or cylindrical) improvement of more than 0.5D

Refractive Improvement* UCVA improvement

73.3% 87.5 %

Pre-treatment

Post-treatment 1

month

Post-treatment

3 month

UCVA(logMAR)* 0.38±0.51 0.17±0.41 0.15±0.39

BCVA(logMAR) 0.01±0.06 0.01±0.07 0.01±0.08* p < 0.05, paired T test for pre-treatment & Post-treatment 3 months

Refractive error and UCVA changes through 3 months treatment

Pre-Tx Post-Tx 1M Post-Tx 3M

UCVA L

ogM

AR

0.0

0.3

0.6

Change of UCVA(LogMAR)Change of UCVA(LogMAR)

UCVA (LogMAR) improved significantly through 3 months treatment.(p<0.05)

ConclusionConclusion

• UCVA improved in 87.5% of patients much more than that of refractive error improvement(73.3%).

• It is suggested that IOP lowering may induce the change of corneal curvature, according to 1-month result.

• IOP lowering agents may be helpful to reduce myopic regression.

DiscussionDiscussion

• Although 3-month result showed no statistically significant change in corneal curvature, it is still though to be important mechanism that IOP lowering may induce the change of corneal curvature.

• Long term follow-up should be needed.

• We stopped the medication at 3 months and are evaluating patients to confirm the effect and mechanism.