PMID- 11471997
OWN - NLM
STAT- MEDLINE
DCOM- 20011204
LR  - 20220210
IS  - 1081-597X (Print)
IS  - 1081-597X (Linking)
VI  - 17
IP  - 4
DP  - 2001 Jul-Aug
TI  - Anterior corneal optical aberrations induced by photorefractive keratectomy for 
      hyperopia.
PG  - 406-13
AB  - PURPOSE: Photorefractive keratectomy (PRK) for hyperopia requires both a 
      steepening of the central cornea and a flattening of the mid-periphery to achieve 
      its effect and is likely to affect the optical aberrations of the eye. METHODS: 
      Nine patients underwent PRK to correct between +2.00 and +4.00 D of hyperopia 
      (first eye treated for each patient) using the Summit Technology Apex Plus 
      excimer laser. Anterior corneal aberrations for pupil diameters of 3, 5.5 and 7 
      mm were estimated from corneal topography data (TMS-1), assuming a uni-index, 
      single surface cornea. Refractive error was assessed using retinoscopy and 
      standard subjective tests. RESULTS: Apart from the intended change in refraction 
      (mean spherical equivalent manifest refraction, +4.60 +/- 1.60 D before surgery 
      and +0.70 +/- 1.60 D at 1 year after surgery), the most significant change was in 
      spherical aberration. Anterior corneal spherical aberration was positive (+1.60 
      +/- 0.60 D for a 5.5-mm pupil) before surgery and became negative after surgery 
      (-1.80 +/- 1.20 D at 1 year). The change in spherical aberration was related to 
      the achieved change in refractive error. CONCLUSIONS: The large change 
      (approximately 3.00 D) in spherical aberration (from positive to negative 
      aberration) has implications for the optical performance of the whole eye, where 
      the effects of lenticular aberration must also be considered.
FAU - Oliver, K M
AU  - Oliver KM
AD  - Department of Vision Sciences, Glasgow Caledonian University, UK. 
      K.Oliver@gcal.ac.uk
FAU - O'Brart, D P
AU  - O'Brart DP
FAU - Stephenson, C G
AU  - Stephenson CG
FAU - Hemenger, R P
AU  - Hemenger RP
FAU - Applegate, R A
AU  - Applegate RA
FAU - Tomlinson, A
AU  - Tomlinson A
FAU - Marshall, J
AU  - Marshall J
LA  - eng
PT  - Journal Article
PL  - United States
TA  - J Refract Surg
JT  - Journal of refractive surgery (Thorofare, N.J. : 1995)
JID - 9505927
SB  - IM
MH  - Cornea/*pathology/surgery
MH  - Corneal Topography
MH  - Humans
MH  - Hyperopia/*surgery
MH  - Lasers, Excimer
MH  - Myopia/diagnosis/*etiology
MH  - Photorefractive Keratectomy/*adverse effects
MH  - Refraction, Ocular
MH  - Visual Acuity
EDAT- 2001/07/27 10:00
MHDA- 2002/01/05 10:01
CRDT- 2001/07/27 10:00
PHST- 2001/07/27 10:00 [pubmed]
PHST- 2002/01/05 10:01 [medline]
PHST- 2001/07/27 10:00 [entrez]
AID - 10.3928/1081-597X-20010701-01 [doi]
PST - ppublish
SO  - J Refract Surg. 2001 Jul-Aug;17(4):406-13. doi: 10.3928/1081-597X-20010701-01.