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.Comparison of Ectasia versus Pseudoectasia using the Ectasia Risk Factor Score System
Karen B. Reyes ; Emerson M. Cruz ; Melody Ana T. Daclan ; Robert Edward T. Ang
Acta Medica Philippina 2024;58(Early Access 2024):1-11
Objectives:
To evaluate and compare ectasia and pseudoectasia in post-myopic LASIK patients presenting with
corneal topographic changes indicative of ectasia using the Ectasia Risk Factor Score System (ERFSS).
Methods:
Single-center retrospective comparative case series of a consecutive chart review of cases in 18 years
who underwent bilateral myopic-LASIK and showed topographic changes indicative of ectasia.
Results:
Four patients were included. Group 1: pseudoectasia eyes, consisting of two patients with bilateral
pseudoectasia, and Group 2: ectasia eyes, consisting of two patients with unilateral ectasia. The clinical course of the cases was discussed and compared based on the ERFSS parameters: topography pattern, residual stromal bed thickness, age, preop thinnest cornea, and pre-operative spherical equivalent (SE) manifest refraction (MR). Group 1 scored zero to low risk for developing ectasia while Group 2-eyes with ectasia scored moderate risk. The predictive value of the ERFSS was 1 in this study.
Conclusion
The ERFSS is a good measure in deciding the suited treatment plan for patient undergoing refractive procedure. Knowing the clinical course of ectasia and pseudoectasia is helpful in the therapeutic approach since pseudoectasia is reversible when identified and managed early as seen in this study.
Dilatation, Pathologic
3.Demographic and clinical profile of patients who underwent refractive surgery screening.
Robert Edward T. Ang ; Erwin E. Camus ; Mark Christian R. Rivera ; Dennis C. Vizconde ; Lilette Marie B. Canilao ; Niccolo Zandro R. Valencia
Philippine Journal of Ophthalmology 2015;40(2):64-71
OBJECTIVE: To describe the demographic and clinical profile of patients who underwent refractive surgery screening.
METHODS: Medical records of patients who sought consult for refractive surgery from January 2010 to December 2014 at a refractive center were reviewed and analyzed. The preoperative clinical conditions, optical characteristics of myopes and hyperopes, refractive screening tests, and causes for disqualification were determined.
RESULTS: A total of 1215 patients who sought consult for refractive surgery had a mean age of 36.45 ± 11.60 years. Seven hundred ten (58.44%) were females and 860 (70.78%) were Filipinos. Nine hundred eighty eight (81%) were myopes. The mean manifest refractive spherical equivalent (MRSE) for myopic patients was -4.41D±2.98 with mean uncorrected distance vision (UCDVA) of 20/400 (logMAR 1.26) and mean best-corrected distance vision (BCDVA) of 20/20 (logMAR 0.02). For hyperopic patients, the mean MRSE was +1.33D±3.76 with mean UCDVA of 20/40 (logMAR 0.33) and mean BCDVA of 20/20 (logMAR 0.001). Reasons for disqualification from undergoing a refractive procedure included thin cornea (5.27%), irregular corneal topography (2.39%), steep cornea (0.78%), high refractive errors (0.41%), optic nerve (0.41%), and retina (0.25%) pathologies.
CONCLUSION: Patients who underwent screening for refractive surgery were young, mostly female, with myopic refractive errors. LASIK remained the most popular refractive surgery procedure.
Human ; Male ; Female ; Adult ; Keratomileusis, Laser In Situ ; Corneal Topography ; Hyperopia ; Myopia ; Refractive Errors ; Optic Nerve ; Retina ; Cornea ;
4.A five-year review of refractive procedures, outcomes and complications.
Robert Edward T. Ang ; Clarissa Marie S. Tady ; Niccolo Zandro R. Valencia ; Lilette Marie B. Canilao ; Dennis C. Vizconde ; Mark Christian R. Rivera
Philippine Journal of Ophthalmology 2015;40(2):72-80
OBJECTIVE: To evaluate the visual and refractive outcomes of LASIK, PRK, phakic IOL, and Supracor as treatment for errors of refraction, including presbyopia, performed at a private eye center.
METHODS: This is a retrospective, single-center, single-surgeon study that reviewed the surgical outcomes of patients who underwent LASIK, PRK, phakic IOL, and Supracor from January 2010 to December 2014. Main outcome measures were postoperative uncorrected and corrected distance, intermediate, and near visual acuity (for Supracor), and mean manifest-refraction spherical equivalent (MRSE) of patients who had at least 1 month follow up. Complications and enhancements were analyzed independently.
RESULTS: Data were analyzed from 1,366 eyes of 771 patients. LASIK was the most commonly performed procedure (68%), followed by PRK (18.3%), Supracor (10.2%), and phakic IOL (3.7%). The postoperative mean MRSE at 1 month for LASIK, PRK, and phakic IOL were -0.08 ± 0.36, +0.06 ± 0.52 and -0.11 ± 0.44, respectively. The mean postoperative logMAR uncorrected distance visual acuity (UDVA) at 1 month for LASIK, PRK, and phakic IOL were 0.02 ± 0.10, 0.07 ± 0.12, 0.001 ± 0.09, respectively. In the Supracor group, the mean preoperative and postoperative spherical equivalent were +1.12 ± 0.8 and -0.76 ± 0.62, respectively. The mean postoperative logMAR UDVA and uncorrected near visual acuity (UNVA) for Supracor were 0.24 ± 0.19 and 0.02 ± 0.08, respectively. The most common postoperative complication was symptomatic dry eye (13%). Regression and off-target outcomes occurred in 24 (1.8%) and 13 eyes (1%), respectively. Overall enhancement rate was 2%.
CONCLUSION: LASIK remained to be the most common refractive procedure, with femtosecond laser-created flap becoming the norm. Refractive and visual outcomes showed good efficacy with all the refractive procedures. Complication and enhancement rates were low.
Human ; Adult ; Keratomileusis, Laser In Situ ; Presbyopia ; Visual Acuity ; Eye ; Surgeons ; Postoperative Complications ; Outcome Assessment (health Care)
5.The quality of life in patients with non-surgical and surgical presbyopic corrections.
Robert Edward T. Ang ; Abigail O. Panganiban ; Ma. Melizza Theresa Toledo-Ramirez ; Gladness Henna A. Martinez ; Dennis C. Vizconde
Philippine Journal of Ophthalmology 2015;40(1):11-17
OBJECTIVE: To compare the quality of life using the National Eye Institute Refractive Error Quality of Life (NEI-RQL) instrument in 40-60 year-old patients with reading glasses and presbyopic LASIK correction and in 60-80 year-old patients with monofocal and multifocal intraocular lenses (IOLs).
METHODS: Patients aged 40-80 years old with reading glasses (group 1a) or presbyopic LASIK treatment (group 1b) and bilateral pseudophakia with monofocal (group 2a) or multifocal IOLs (group 2b) were recruited. All patients answered the NEI-RQL questionnaire. The responses in the self-administered questionnaires were collated, analyzed, and compared between the subgroups.
RESULTS: One hundred fifty patients (median age 60 years, range 41-80 years) completed the NEI-RQL questionnaire. Subjects (age 41-59 years) who underwent presbyopic LASIK correction had a higher mean NEI-RQL (p=0.19) and higher subscale score for satisfaction (p=0.42) than those wearing reading glasses. However, the differences were not satistically significant.
CONCLUSION: Presbyopic LASIK improved uncorrected near visual acuity and provided spectacle independence in presbyopes; however, patient satisfaction was similar to those who with reading glasses. Multifocal IOLs significantly improved uncorrected near visual acuity and spectacle independence in pseudophakic patients with high patient satisfaction.
Human ; Male ; Female ; Aged ; Middle Aged ; Adult ; Eyeglasses ; Lenses, Intraocular ; Keratomileusis, Laser In Situ ; Pseudophakia ; Refractive Errors ; Presbyopia ; Quality Of Life
6.Comparison of the rotational stability of different toric intraocular lens implants.
Kate C. Torio ; Robert Edward T. Ang ; Gladness Henna A. Martinez ; Jocelyn Therese M. Remo
Philippine Journal of Ophthalmology 2014;39(2):67-72
OBJECTIVE: To compare the rotational stability and cylinder reduction of different toric intraocular lenses (IOLs).
METHOD: This was a prospective, cross-sectional study of 68 eyes that had at least 0.75 diopters (D) of corneal astigmatism prior to cataract surgery and were at least 3 months post-toric IOL implantation (Envista, AcrySof, FineVision). Patients recruited underwent visual acuity testing, manifest refraction, pupil dilation, and toric IOL axis determination. Actual axis position was obtained and compared to the intended axis calculated from the tonic IOL calculator. Any difference between the two was considered an axis deviation. Main outcome measures were postoperative deviation of the IOL axis from the intended axis, uncorrected distance visual acuity (LIDVA), best corrected distance visual acuity (BCDVA), manifest refraction, and cylinder reduction.
RESULTS: There was no significant difference in the rotational stability of the three different types of toric IOLs (p=0.95). Mean axis deviation for .AcrySof, Envista, and FineVision were 2.43, 2.66, and 2.75 degrees, respectively. There was a significant decrease in the cylinder from preoperative to postoperative levels for all groups (p=0.00 for Envista, p=0.03 for AcrySof, and p=0.00 for Fine-Vision). There were significant improvements in the mean UCVA and BCDVA after cataract surgery and implantation of toric IOLs for all three groups.
CONCLUSION: The three IOL platforms (AcrySof, Envista, and FineVision) showed good rotational stability and significant cylinder reduction:Visual and refractive outcomes improved after surgery.
Human ; Lenses, Intraocular ; Astigmatism ; Dilatation ; Pupil ; Visual Acuity ; Cataract Extraction ; Cataract ; Outcome Assessment (health Care)
7.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
8.Survey of glaucoma practice patterns among members of The Philippine Glaucoma Society
Edgar Felipe U. Leuenberger ; James Paul S. Gomez ; Karlo Paolo L. Alejo ; Robert Edward T. Ang ; Maria Zita Zagala-Meriales ; Pamela C. Allarey ; Aldo Mar B. Cariaga ; John Mark S. De Leon ; Sammy L. Ang ; ; ;
Philippine Journal of Ophthalmology 2020;45(1):9-18
OBJECTIVE: To identify the glaucoma clinical practice patterns among the members of the Philippine Glaucoma Society (PGS) from 2015 to 2016 using an online survey.
METHODS: An online link was sent to each consenting PGS member which directed them to two poll sites. These sites asked questions about demographics and their preferred clinical practice patterns. Frequency and percent distributions were used to analyze the data.
RESULTS: There was a high response rate from PGS members at 97% (42 out of 43 members). More than half of respondents (51%, n=22) defined glaucoma as glaucomatous optic neuropathy with an evident visual field loss. IOP was routinely measured by 90% (n=38) of the respondents with majority preferring to use the Goldmann applanation tonometer (GAT) (98%, n=41). Gonioscopy was done on all new patients by all PGS members but only 62% did regular gonioscopy on follow-up consultations. Most of the respondents relied on the 90D lens (88%) to assess the optic nerve. Visual field examination (VFE) was routinely requested by all respondents. Pachymetry and anterior segment optical coherence tomography (AS-OCT) were used sparingly at only 43% and 12% respectively. Appositional angle closure was addressed by performing laser iridotomy with majority of the respondents preferring a site that is covered by the upper eyelid (57%). Prostaglandin analogues were the top choice as first-line monotherapy for eyes with open-angle glaucoma. Majority of the respondents (55%) opted to do laser trabeculoplasty (LTP) as an adjunct to medical therapy. Mitomycin-C was the preferred intraoperative antimetabolite for trabeculectomy by 98% (n=41). Ahmed (71%, n=30) was the more favored glaucoma drainage device (GDD) by our respondents over Baerveldt (19%, n=8).
CONCLUSION: This survey showed majority of the glaucoma practices of PGS members appear to adhere to the current clinical practice guidelines.
Philippines
;
Glaucoma
;
Tetrahymenina
;
Surveys and Questionnaires
9.Measurement of accommodative amplitude using wavefront aberrometer.
Robert Edward T. Ang ; Jennifer Aurea S. Sarmiento ; Jocelyn Therese M. Remo ; Gladness Henna A. Martinez ; Lilette Marie B. Canilao
Philippine Journal of Ophthalmology 2015;40(1):3-10
OBJECTIVE: To measure and compare the accommodative amplitude of Filipino patients with different accommodative conditions using a wavefront aberrometer.
METHODS: A total of 120 eyes of 67 patients seen in a private eye center were included and divided into two groups (phakic and pseudophakic). After undergoing routine ophthalmologic examination that included manifest refraction and visual acuity testing, accomodative amplitude was measured using the iTraceTM wavefront aberrometer. Comparison of the measurements was made between the accommodative amplitude of phakic pre-presbyopes and presbyopes, and between eyes implanted with monofocal and accommodating intraocular lenses (IOLs).
RESULTS: The mean age of the pre-presbyopes was 27 years, presbyopes 50 years, monofocal IOL 69 years and accommodating IOL 67 years. The mean accommodative amplitude of the pre-presbyopes was 1.64 ± 1.06D, presbyopes 0.99 ± 0.42D, monofocal IOL 0.36 ± 1.16D, and accommodating IOL 0.94 ± 0.89D. The pre-presbyopes had a higher accommodative amplitude than the presbyopes (p=0.008), while the accommodating IOL subgroup had a higher amplitude than the monofocal IOL subgroup (p=0.02). Increasing age was correlated with decreasing amplitude in the phakic group (r2=0.926). There was no correlation between refractive error and amplitude of accommodation in the phakic and pseudophakic groups (r2=0.02 for both groups).
CONCLUSION: The wavefront aberrometer is a reliable tool in objectively measuring accommodative amplitude. Pre-presbyopes and accommodating IOLs were shown to have higher amplitudes of accommodation than presbyopes and monofocal IOLs.
Human ; Male ; Female ; Adult ; Lenses, Intraocular ; Accommodation, Ocular ; Presbyopia ; Visual Acuity ; Refractive Errors
10.A comparative study between the schwind and zyoptix XP microkeratomes
Maria Cecilia P. Garcia ; Joanne A. Barleta ; Gladness HA HA Martinez ; Robert Edward T. Ang
Philippine Journal of Ophthalmology 2010;35(1):10-14
Objectives To compare the flap thickness created by two different microkeratomes and its effect on visual outcomes. Methods This prospective study involved 32 eyes of 16 patients who underwent laser in situ keratomileusis (LASIK). Flap creation was randomly assigned to either the Schwind (110 ?m) or Zyoptix XP (120 ?m) microkeratome. Flap thickness was measured using the subtraction technique. Uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), low-contrast sensitivity, and aberrometry measurements were compared preoperatively and at 6 months postoperatively. Results The mean flap thickness was 97 ± 13 ?m (range, 81 to 116 ?m) and 146 ± 27 ?m (range, 71 to 181 ?m) using the Schwind and XP respectively. The mean deviation from the labeled predicted thickness was –13 ± 13 ?m and 26 ± 27 ?m respectively, and this difference was statistically significant (p = 0.002). Three eyes had flap displacement, 1 had loose epithelium, and 1 had flap striae in the Schwind group. There were no complications in the XP group. At 6 months, 71% of eyes had UCVA of 20/20 or better in both groups. All eyes attained BCVA of 20/30 or better with spherical equivalent within ±1D of targeted emmetropia in both groups. Low-contrast sensitivity scores were higher in the Schwind group in most frequencies; however, the differences were not statistically significant. The mean change in the total higher-order aberration (HOA), trefoil, coma, quadrafoil was comparable between the groups. The mean change in spherical aberration was smaller (p = 0.03) in the Schwind (0.12 ± 0.35) than in the XP group (0.96 ± 1.3). Conclusion Flap thickness was more predictable with the Schwind than the XP. Schwind flaps were thinner, which may have resulted in more flap complications. Vision and refractive results were similar for both groups. There was no statistically significant difference in HOA; however, spherical aberration was significantly lower in the Schwind.
Keratomileusis
;
Laser In Situ