Research Article

Risk Assessment for Corneal Ectasia following Photorefractive Keratectomy

Table 3

Literature review—demographic and pre- and postoperative data.

Eye numberReference yearNumber of eyesNumber of pts.Age (years)SexEyePreoperative refractionTopographic findingsMeasured pachyc (μm)Ablation depth (μm)Calculated RSBd (μm)RetreateTime to onset of ectasia (months)Family historyOcular history
Sphere (D)Cylinder (D)BSCVAa (Snellen)SEQb (D)

12000 [12]2141FR−4.00−3.500.7−5.75KCNf or FFKCNg1
2L−5.50−2.500.7−6.75KCN or FFKCN1
32002 [11]2234ML−12.00−1.500.5−12.75Normal144146Amblyopia
439MR−3.00−4.500.3−5.25KCN010KCN
52006 [6]2122MR−1.50−1.001.0−2.00D sign49532413052
6L−1.50−1.001.0−2.00SRAXh −60°
I-Si −0.9 (susp. FFKCN)
49530415052
72006 [13]4237MR−1.50−2.501.0−2.75I-S ~34725336900.25
8L−4.00−3.000.7−5.50Central steep.j44110029100.25
940MR−4.75−3.751.0−6.63SBTk50998365010Sister had bil. PKlEye rubber
10L−5.25−4.001.0−7.25SBT50810635601.5
112006 [9]2142MR−9.25−1.250.8−9.88SBT47714228518
12L−8.25−2.000.8−9.25SBT48113329818
132007 [10]5438FR−7.00−3.00−8.50Inf. steep.m520036
14L−6.00−4.00−8.00Inf. steep.510036
1531MR−4.50−1.751.0−5.38SBT487013LE KCN s/p PKn
1631ML−3.75−0.501.0−4.00Inf. steep., SRAX49291351030
1738FL−1.50−1.251.0−2.13Inf. Steep.5095040904
182007 [8]2135MR−3.00−1.501.0−3.75ABTo4976738000.5Sister with KCNEye rubber
19L−3.00−2.001.0−4.00ABT5117039100.5
202008 [7]1125MR−5.75−1.750.8−6.63I-S ~450070380060
Total2013

Mean34.8−4.75−2.310.8−5.914948036221.62
SD±6.0±2.78±1.17±0.2±2.87±20±35±45±20.7
Min22−12.00−4.500.3−12.75441302850.3
Max42−1.50−0.501.0−2.0052014241560.0

aBest spectacle-corrected visual acuity; bspherical equivalent; cpachymetry; dresidual stromal bed; enumber of enhancements; fkeratoconus; gform fruste keratoconus; hskewed radial axis; iinferior-superior value; jcentral steepening; ksymmetric bowtie; lbilateral penetrating keratoplasty; minferior steepening; nleft eye keratoconus status post penetrating keratoplasty; oasymmetric bowtie. Measured RSB.