1.Comparison of flap thickness, visual outcomes, and higher order aberrations in eyes that underwent LASIK flap creation using a femtosecond laser versus a mechanical microkeratome
Rachelle C. Perez ; Emerson M. Cruz ; Albert G. Dela Cruz, Jr. ; Robert Edward T. Ang
Philippine Journal of Ophthalmology 2012;37(2):83-90
Objective:
To compare the predictability of flap thickness, visual and refractive outcomes, and higher order
aberrations in eyes that underwent myopic LASIK using either a Technolas femtosecond laser or a Zyoptix XP
mechanical microkeratome for flap creation.
Methods:
The study involved a total of 44 eyes of 22 patients who underwent LASIK. Flap creation was randomized
to using the Technolas femtosecond laser in one eye and Zyoptix XP microkeratome in the contralateral eye. Flap
thickness was measured intraoperatively using ultrasonic pachymetry and postoperatively using the Visante ASOCT. Refractive outcome, visual acuity (VA), higher order aberrations, and contrast sensitivity were compared
between the two groups.
Results:
Twenty-two patients had LASIK for myopia or myopic astigmatism. Using ultrasonic pachymetry
intraoperatively, the mean flap thickness was 134 (±10) um and 124 (±23) um in the femtosecond (FS) and
microkeratome (MK) groups respectively. Comparing the deviation of the actual from the intended flap thickness,
the FS group had statistically lower standard deviation compared to the MK group (p=0.04). Using the AS-OCT,
the mean flap thickness at 3 months postoperatively was 119 (±10.82) um and 123 (±15.77) um in the FS and MK
groups respectively. The difference in standard deviation between the two groups did not reach statistical significance
(p=0.19). The mean spherical equivalent at 3 months was -0.45D (±0.42) and -0.13D (±0.16) respectively. Eightynine percent (89%) of eyes had uncorrected VA of 20/20 or better in both groups. All eyes attained best corrected VA of 20/20 or better in both groups. Differences in total higher order aberrations (p=0.09) and contrast sensitivity
scores (p=0.47) were not statistically different between the two groups.
Conclusion
Flap thickness predictability was better using the Technolas femtosecond laser compared to the
XP microkeratome blade. Visual and refractive outcomes, higher order aberrations, and contrast sensitivity were
comparable between the 2 groups.
Keratomileusis, Laser In Situ
;
Lasers, Excimer
2.Clinical comparison of visual and refractive outcomes of two models of accommodative intraocular lenses
Robert Edward T. Ang ; Constancia C. Zayco ; Emerson M. Cruz ; Albert G. Dela Cruz, Jr.
Philippine Journal of Ophthalmology 2012;37(1):24-32
Objective:
To evaluate the visual and refractive outcomes of eyes implanted with the Crystalens HD and the
Crystalens AO intraocular lens.
Methods:
We retrospectively reviewed the records of 159 eyes of 100 patients implanted with the Crystalens
HD IOL and 108 eyes of 66 patients implanted with the Crystalens AO IOL. Visual and refractive outcomes preoperatively and postoperatively were assessed and compared between the lenses.
Results:
At 1 year, uncorrected distance VA was 20/30 in 78% of eyes in the HD and 76% of eyes in the AO
groups. Uncorrected intermediate VA was 20/30 in 90% of eyes in both groups. Uncorrected near VA was J3 in
92% in the HD and 90% in the AO groups. Comparing the two groups, the difference in uncorrected distance
(p=0.60), intermediate (p=0.77), and near (p=0.64) vision was not statistically significant. Spherical equivalent was
-0.42D +/-0.51D in the HD and -0.6 +/-0.48D in the AO groups (p=0.10).
Conclusion
Refractive outcomes were similar between the Crystalens HD and AO groups. Mild myopic refractive
outcomes were targeted and achieved in both lens groups. These refractive outcomes provided good uncorrected
distance, intermediate, and near vision postoperatively.
Multifocal Intraocular Lenses
3.Refractive and visual outcomes of surgical treatments for high myopia
Robert Edward T. Ang ; Maria Rachelle Katrina C. Solis ; Maria Luisa Patricia C. Solis ; Emmerson M. Cruz ; Albert G. Dela Cruz ; Rosalie Mae M. Reyes
Philippine Journal of Ophthalmology 2013;38(1):21-28
Objective:
To present the refractive and visual outcomes of refractive surgical treatment options in high myopia.
Methods
This was a retrospective review of patients diagnosed with high myopia (manifest refractive spherical
equivalent [MRSE] ≥-6.00D) who underwent one of the following procedures: laser-in-situ keratomileusis (LASIK),
photorefractive keratectomy (PRK), phakic IOL implantation with the Staar Implantable Collamer Lens (ICL), or
Alcon Cachet Phakic IOL. Eyes with best corrected distance vision of less than 20/30 due to amblyopia or other
eye pathologies were excluded.
Keratomileusis, Laser In Situ
;
Photorefractive Keratectomy
4.Incidence, indications, and outcomes of Yag Capsulotomy in eyes Implanted with an accommodating intraocular lens
Robert Edward T. Ang ; Angela Adelaida J. Samano ; Rosalie Mae M. Reyes ; Emerson M. Cruz ; Albert G. Dela Cruz ; Maria Luisa Patricia C. Solis
Philippine Journal of Ophthalmology 2013;38(1):13-20
Objectives:
To do report the incidence of capsular changes in Crystalens-implanted eyes and analyze the indications and outcomes of yag capsulotomy.
Methods:
We reviewed the records of 411 eyes of 258 patients implanted with the Crystalens IOL. Capsular change
indications for yag capsulotomy were posterior capsular opacification (PCO), lens tilt, and capsular striae. Eyes in
each indication were further subdivided into therapeutic yag (TY) and prophylactic yag (PY) groups. Outcomes
before and after yag capsulotomy were analyzed.
Results:
Ninety of 411 crystalens-implanted eyes (22%) had undergone yag capsulotomy. Sixty-one eyes had PCO,
12 had lens tilt, and 17 had striae. Twenty-seven eyes belonged to the therapeutic (TY) and 63 eyes to the prophylactic
(PY) yag subgroups. The mean interval between phacoemulsification and yag capsulotomy was 10 months. In the
TY PCO subgroup, uncorrected distance visual acuity (UDVA) changed from 20/40 pre-yag to 20/25 post-yag,
uncorrected near visual acuity (UNVA) from J3 to J2, manifest refraction spherical equivalent (MRSE) from -0.43D
to -0.2D. In the TY tilt subgroup, UDVA changed from 20/50 to 20/30, UNVA was unchanged at J2, and MRSE
from -1.21D to -0.89D. In the TY striae group, UDVA changed from 20/50 to 20/30, UNVA from J3 to J2, and
MRSE from 0.62D to -0.4D. In the PY PCO subgroup, UDVA was unchanged at 20/25, UNVA unchanged at J2,
and MRSE changed from -0.52D to -0.47D. In the PY tilt subgroup, UDVA changed from 20/25 to 20/20, UNVA
unchanged at J2, and MRSE changed from -0.87D to -0.45D. In the PY striae subgroup, UDVA was unchanged at
20/30, UNVA changed from J3 to J2, and MRSE changed from -0.62D to -0.7D.
Conclusion
Capsular changes occurred after Crystalens implantation that necessitated yag capsulotomy. Once
vision has deteriorated, a therapeutic yag treatment can help improve vision. If capsular changes have occurred but
vision has not deteriorated, a prophylactic yag capsulotomy can stabilize visual and refractive outcomes.
Multifocal Intraocular Lenses
;
YAG capsulotomy