Hypermetropes and Myopes Mangat S Kumar B V Prasad S Arrowe Park Hospital Wirral University Hospital NHS Trust No financial interests Introduction Cataract surgery in patients with myopia and ID: 225169
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Slide1
Biometric Accuracy in High Hypermetropes and Myopes
Mangat
S, Kumar B V,
Prasad
S
Arrowe
Park Hospital,
Wirral University Hospital NHS Trust
No financial interestsSlide2
Introduction
Cataract surgery in patients with myopia and
hypermetropia
can be technically challenging .
These challenges arise due to extremes of axial length which can lead to complications during biometry.
This can lead to potential intra and postoperative complications particularly with postoperative surprises particularly
anisometropia
.
Hence obtaining accurate biometry in these patients is essential to ensure that the cataract surgery is successful.Slide3
Methods
Retrospective review of
medisoft
database was undertaken of cataract surgery carried out between Jan 2005 - September 2009
Surgery was carried out by Consultants, Fellow and Registrars.
Myopia is defined when patient has an axial length more than 26mm
Hypermetropia
is defined when patient has an axial length less than 22mm
Preoperative refraction, biometry measurements , visual acuity pre and post cataract surgery were all documented.
Deviation from
- predicted postoperative outcome and
- final best corrected visual acuity were recordedSlide4
Results
Axial length < 22mm
Axial length >26mm
Number of Patients
632
245
Number of Operations
764297Data Available585225Mean Age of Patient76.3 68.5Age Range37-9513-93Mean Post Op Spherical Equivalent-0.01+/-1.20 (SD) (95%CI +/- 0.11)-0.70 +/-0.95(SD) (95% CI +/-0.12)Mean Deviation From Predicted Refraction-0.01+/- 0.90 (SD) (95% CI +/- 0.08)-0.09+/- 1.34 (SD) (95% CI +/- 0.17)Predicted Post Operative Refraction +/- 1 D of predicted484192<-1D of predicted5420>1D of predicted4512
Slide5
Slide6Slide7Slide8
Main IOL Models Inserted
IOL
Mode
(%)
Axial Length <22mm
Axial Length 22-26mm
Axial Length >26mm
B&L L161AO50.9547.8848.55B&L L161SE30.1327.9926.97Chiron soflex 214.6721.219.5B&L M1601.741.831.24Slide9
Conclusions
Postoperative refraction in the <22mm and >26mm groups was within +/-1D in 84% and 86 % respectively
There was no statistically significant difference between the mean post operative spherical equivalent -0.01 (<22mm) and 0.70 (>26mm). Paired Student t Test >0.05
There was no statistically significant difference between the mean deviation from predicted refraction -0.01 (<22mm) and -0.09 (>26mm). Paired student t Test >0.05Slide10
Conclusions 89.5% cases with Axial Lengths 22-26mm had a postoperative refraction of +/- 1D
Some postoperative surprises were noted as a result of Biometry errors which was rectified later with further surgery.
It may be wise to discuss this finding preoperatively when dealing with patients with extremes of axial lengthSlide11
Available Evidence
Zuberbuhler
et al state that 53.2% of patients were +/- 1D of predicted in those with axial lengths above 30mm
Lyle et al studied 106 highly myopic eyes. Postoperative corrected visual acuity was 20/40 or better in 94% of eyes, and uncorrected visual acuity was 20/40 or better in 77% of eyes at 27 months in those with axial lengths >26mm
Maclaren
et al state 55% patients were +/- 1D of
predcited
in 76 eyes requiring IOLs between 30-35DSlide12
References1.
Zuberbuhler
B,
Seyedian
M, Tuft S.
Phacoemulsification
in eyes with extreme axial myopia. J Cataract Refract
Surg. 2009 Feb;35(2):335-40. 2. Lyle et al. Phacoemulsification with intraocular lens implantation in high myopia. J Cataract Refract Surg. 1996 Mar;22(2):238-42.3. MacLaren RE et al. Biometry and formula accuracy with intraocular lenses used for cataract surgery in extreme hyperopia. Am J Ophthalmol. 2007 Jun;143(6):920-931.