bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Advanced Human Eye Model (AHEM): A Personal Binocular Eye Modeling System Inclusive of Refraction, Diffraction, and Scatter
Authors: Donnelly William 
Published: September 2019

Purpose
To present a commercially available software tool for creating eye models to assist the development of ophthalmic optics and instrumentation, simulate ailments or surgery-induced changes, explore vision research questions, and provide assistance to clinicians in planning treatment or analyzing clinical outcomes.

Methods
A commercially available eye modeling system was developed, the Advanced Human Eye Model (AHEM). Two mainstream optical software engines, ZEMAX (ZEMAX Development Corp) and ASAP (Breault Research Organization), were used to construct a similar software eye model and compared. The method of using the AHEM is described and various eye modeling scenarios are created. These scenarios consist of retinal imaging of targets and sources; optimization capability; spectacles, contact lens, and intraocular lens insertion and correction; Zernike surface deformation on the cornea; cataract simulation and scattering; a gradient index lens; a binocular mode; a retinal implant; system import/export; and ray path exploration.

Results
Similarity of the two different optical software engines showed validity to the mechanism of the AHEM. Metrics and graphical data are generated from the various modeling scenarios particular to their input specifications.

Conclusions

The AHEM is a user-friendly commercially available software tool from Breault Research Organization, which can assist the design of ophthalmic optics and instrumentation, simulate ailments or refractive surgery–induced changes, answer vision research questions, or assist clinicians in planning treatment or analyzing clinical outcomes. [
J Refract Surg
. 2008;24:976–983.]
In Vivo Application and Imaging of Intralenticular Femtosecond Laser Pulses for the Restoration of Accommodation
Authors: Schumacher Silvia , Fromm Michael , Oberheide Uwe , Gerten Georg , Wegener Alfred , Lubatschowski Holger 
Published: September 2019

Purpose
According to the Helmholtz theory of accommodation, one major cause of the development of presbyopia is the increasing sclerosis of the crystalline lens. One concept for regaining the elasticity of the sclerosing lens is intralenticular treatment by femtosecond laser pulses.

Methods
The feasibility of applying and imaging in vivo microincisions by femtosecond laser pulses was evaluated in five rabbit lenses with a new high repetition rate (100 kHz) femtosecond laser unit. The treated eyes were monitored using optical coherence tomography (OCT) and Scheimpflug imaging for localizing and studying the tissue effects of the incisions. The rabbits were investigated preoperatively, immediately postoperatively, and 14 days after treatment.

Results
The procedure, termed femtosecond-lentotomy, was successfully applied to the left lens of each rabbit. The laser microincisions within the crystalline lens were detectable with OCT and Scheimpflug imaging, which emphasizes the integral role these technologies play in targeting and characterizing postoperative tissue effects. The imaging within the lens showed a progressive fading of the incisional opacities generated by the femtosecond laser after 14 days with no detectable cataract formation.

Conclusions

It is possible to create microincisions inside the crystalline lens within an acceptably short treatment time (<30 seconds). The 14-day follow-up did not show undesirable side effects, such as cataract formation, after intralenticular laser treatment. [
J Refract Surg
. 2008;24:991–995.]
Mitomycin C in Photorefractive Keratectomy
Authors: Shalaby Ashraf , Kaye Geoffrey B. , Gimbel Howard V. 
Published: September 2019

Purpose:
To evaluate the outcome of primary or retreatment photorefractive keratectomy (PRK) or photo-therapeutic keratectomy (PTK) with mitomycin C (MMC) 0.02% applied prophylactically intraoperatively for the prevention of haze and regression in cases of significant haze and regression after primary PRK, due to previous radial keratotomy (RK), in primary PRK eyes with high myopia, and in corneas with a previous superficial foreign body scar.

Methods:
This was a retrospective evaluation of 34 eyes treated with PRK or PTK and intraoperative MMC. Mitomycin C was applied immediately after laser ablation. Postoperative examinations were conducted 3 and 7 days after surgery and monthly for 6 months. Haze was graded on a standard 0+ (clear cornea) to 4+ (total opacity) scale. Visual acuity was measured as a general baseline indicator.

Results:
Postoperatively, uncorrected visual acuity (UCVA) was 20/20 or better in 21 eyes and 20/25 in 5 eyes with best spectacle-corrected visual acuity (BSCVA) of 20/20 or better. Three eyes achieved UCVA of 20/30 with BSCVA of 20/20 or better; and 5 eyes had UCVA of 20/40 with BSCVA of 20/20 or better. Nineteen (56%) eyes had grade 0+ haze and 15 (44%) eyes had grade 0.5+ haze (trace haze) at 6-month follow-up.

Conclusions:

Mitomycin C 0.02% used prophylactically during PRK or PTK retreatment was effective in preventing significant recurrent haze from developing. In eyes with high myopia or previous RK or scarring, MMC was effective in preventing significant haze formation. [
J Refract Surg
. 2009;25:S93–S97.]
Confocal Microscopy of Corneal Sub-basal Nerve Plexus: A Quantitative and Qualitative Analysis in Healthy and Pathologic Eyes
Authors: Midena Edoardo , Cortese Marta , Miotto Stefania , Gambato Catia , Cavarzeran Fabiano , Ghirlando Alessandra 
Published: September 2019

Purpose:
To validate corneal sub-basal nerve plexus examination by in vivo corneal confocal microscopy.

Methods:
Five parameters of corneal sub-basal nerve plexus in 250 human eyes (nerve fiber length, number of fibers, number of beadings, branching pattern, fiber tortuosity) acquired using in vivo corneal confocal microscopy (Confoscan 4.0; NIDEK Co Ltd) were analyzed. The first operator repeated the parameter analysis twice, performing the 2 evaluations 4 weeks apart. The second operator analyzed the cases once.

Results:
Intraoperator reproducibility of nerve fiber length, number of fibers, and number of beadings (intraclass correlation coefficient [ICC] = 0.96, 0.96, and 0.93, respectively) and interoperator reproducibility (ICC = 0.94, 0.95, and 0.87, respectively) were very good. Intraoperator reproducibility for branching pattern was good (ICC = 0.74), whereas interoperator reproducibility was very good (ICC = 0.81). Reproducibility of fiber tortuosity was good both at intra- and interoperator levels (ICC = 0.69 and 0.60, respectively).

Conclusions:

Corneal confocal microscopy with the NIDEK Confoscan 4.0 represents an in vivo, noninvasive, and reproducible diagnostic technique for the analysis of sub-basal corneal nerve plexus. Methods used to analyze quantitative and qualitative variables were highly reproducible. [
J Refract Surg
. 2009;25:S125–S130.]
NIDEK Optimized Prolate Ablation for the Treatment of Myopia With and Without Astigmatism
Authors: El Danasoury Alaa M. 
Published: September 2019

Purpose:
To report the ocular and corneal higher order aberrations of a pilot trial of optimized prolate ablations for the treatment of myopia.

Methods:
In this prospective study, patients were treated using optimized prolate ablation or conventional ablation. Five patients underwent bilateral optimized pro-late ablation treatment, and nine patients were randomized to receive optimized prolate ablation (OPA group) in one eye and conventional ablation (control group) in the other eye. The mean preoperative manifest refraction spherical equivalent was −4.13±1.17 diopters (D) (range: −8.00 to −1.50 D), with a mean cylinder of −0.42±0.32 D (range: −1.00 to 0.00 D). Predictability, contrast sensitivity, and corneal and ocular aberrations were analyzed out to 6 months postoperatively.

Results:
Postoperative predictability was similar between the two groups. There was an increase in mesopic contrast sensitivity in the OPA group, and the OPA group had higher mesopic contrast sensitivity postoperatively. At 6 months postoperatively, the root-mean-square (RMS) of the total ocular higher order aberrations was 0.47 µm for the OPA group and 0.75 µm for the control group. Ocular spherical aberration was 0.04 µm for the OPA group and 0.22 µm for the control group. Six-month postoperative RMS of corneal spherical aberration was 0.25 µm for the OPA group and 0.46 µm for the control group.

Conclusions:

The preliminary outcomes in this study indicate that optimized prolate ablation-treated eyes had less induction of higher order aberration and spherical aberrations postoperatively. Better contrast sensitivity was noted in eyes that underwent optimized prolate ablation treatment compared with preoperatively. [
J Refract Surg
. 2009;25:S136–S141.]
Outcomes of NIDEK Optical Path Difference Custom Ablation Treatments (OPDCAT) for Myopia With or Without Astigmatism
Authors: Chen Shihao , Wang Yibo , Wang Qinmei 
Published: September 2019

Purpose:
To report refractive and visual acuity outcomes using wavefront-guided optical path difference custom ablation treatments (OPDCAT; NIDEK Co Ltd) for myopia and myopic astigmatism.

Methods:

One hundred eyes of 50 patients with preoperative manifest refraction spherical equivalent (MRSE) of 4.62±1.30 diopters (D) (range: −1.38 to −7.25 D) with mean astigmatism of −0.57±0.37 D (range: 0 to −1.75 D) underwent LASIK with OPDCAT. Eyes that had ⩾5 µm of irregularity preoperatively underwent additional irregularity treatment (irregularity group) and were compared with eyes that did not undergo irregularity ablation (aspheric group). An independent-samples
t
test was used to analyze refractive outcomes at 3 months postoperatively. A
P
value <.05 was considered statistically significant.

Results:

The mean postoperative MRSE was 0.18±0.35 D (range: −0.63 to 1.00 D). Ninety-six (96%) eyes had uncorrected visual acuity of 20/20 or better and 87 (87%) eyes were within ±0.50 D of the intended correction. No eyes lost two or more lines of best spectacle-corrected visual acuity (BSCVA), 1 (1%) eye lost one line of BSCVA, and 99 (99%) eyes maintained gained lines of BSCVA. The MRSE changed 0.02 D between 1 and 3 months postoperatively. A statistically significant increase was noted in higher order aberrations in the entire cohort (
P
<.05) with lower induced higher order aberration and coma aberrations in the irregularity group (
P
<.05).

Conclusions:

LASIK using wavefront-guided OPDCAT ablation with or without irregularity is safe and efficacious for the treatment of myopia with astigmatism. The irregularity treatment induces fewer higher order aberrations than aspheric ablation. [
J Refract Surg
. 2009;25: S142–S147.]
Pseudoaccommodative Cornea Treatment Using the NIDEK EC-5000 CXIII Excimer Laser in Myopic and Hyperopic Presbyopes
Authors: Uy Edward , Go Rory 
Published: September 2019

Purpose:
To investigate the refractive outcomes and spherical aberration of multifocal LASIK to create a distant-dominant center and near-dominant periphery in hyperopic, myopic, and emmetropic presbyopia.

Methods:
One hundred ninety-five eyes with myopic presbyopia and 119 eyes with hyperopic or emmetropic presbyopia that underwent LASIK or epithelial LASIK (epi-LASIK) were assessed out to 3 months postoperatively. All eyes underwent the pseudoaccommodative cornea (PAC) treatment using aspheric ablation profiles and wavefront correction with the NIDEK CXIII excimer laser. Mean preoperative spherical equivalent refraction was −3.80±2.10 diopters (D) for myopic presbyopia and +1.00±0.92 D for hyperopic or emmetropic presbyopia.

Results:
Mean postoperative spherical equivalent refraction was −0.40±0.77 D for myopic presbyopia and +0.15±0.62 D for hyperopic or emmetropic presbyopia. Functional vision, defined as 20/30 or better distance uncorrected visual acuity (UCVA) combined with J3 or better near UCVA, was achieved in 162 (83%) eyes with myopic presbyopia and 103 (87%) eyes with hyperopic or emmetropic presbyopia. An induction of 0.312 µm of spherical aberration was noted at 6 mm for myopic presbyopia treatments and 0.016 µm for hyperopic presbyopia treatments.

Conclusions:

The distance-dominant center used for PAC treatments is effective in emmetropic, myopic, and hyperopic presbyopia. The induced spherical aberration allows for depth of focus in patients with presbyopia. [
J Refract Surg
. 2009;25:S148–S155.]
Bioptics With LASIK Flap First for the Treatment of High Ametropia
Authors: Dvali Merab L. , Tsinsadze Nana A. , Sirbiladze Bella V. 
Published: September 2019

Purpose:
To report the safety and predictability of an alternate sequence of the bioptics procedure.

Methods:
In this prospective study of 50 eyes, phakic intraocular lenses (IOLs) and pseudophakic IOLs were implanted, followed by LASIK. The corneal flap was created, followed by lens implantation 3 days later. Laser ablation was performed to the stromal bed 3 months later. Fifty eyes with varying degrees of refractive error (range of manifest refraction spherical equivalent [MRSE], −19.50 to +8.50 diopters [D]) were treated. Follow-up ranged from 3 months to 4 years postoperatively.

Results:
No intra- or postoperative complications occurred. Postoperatively, MRSE ranged from −0.75 to +0.50 D. Mean residual refractive astigmatism ranged from +0.25 to +1.50 D postoperatively. Postoperative uncorrected visual acuity was 20/20 or better in 82% (41/50) of eyes and 20/40 or better in 98% (49/50) of eyes. No eyes experienced a loss of best spectacle-corrected visual acuity postoperatively.

Conclusions:

This modification of the sequence of procedures for bioptics provided safe and predictable outcomes. [
J Refract Surg
. 2009;25:S160–S162.]
Acular LS Before and During LASIK for the Control of Pain: A Randomized, Masked Contralateral Eye Trial
Authors: Dougherty Paul J. 
Published: September 2019

Purpose:
To assess the effect of ketorolac tromethamine 0.4% (Acular LS; Allergan Inc) drops in controlling LASIK pain.

Methods:
A prospective, randomized, double-masked, placebo-controlled study was performed to evaluate the effect of Acular LS on LASIK pain. Patients were given two unmarked bottles prior to surgery, one containing ketorolac tromethamine 0.4% (ketorolac group) and the other containing Refresh Tears (Tears group). Patients were randomly assigned to instill Acular LS in one eye and Refresh Tears in the fellow eye four times a day beginning 48 hours prior to LASIK, just before the keratome pass, and at the conclusion of surgery. Bilateral simultaneous LASIK was performed on the right eye followed by the left eye. Pain was assessed on a scale of 0 (no pain) to 6 (extreme pain) immediately after surgery on each eye and again 4 to 6 hours after surgery. Patients were evaluated at postoperative day 1 for microstriae and flap slips.

Results:

Sixty eyes of 30 patients were enrolled in the study. No eyes experienced postoperative flap slips or microstriae. The mean postoperative pain score in the Tears group of 1.23±1.33 was significantly higher (
P
=.002) than the postoperative score of 0.53±0.86 in the ketorolac group. The mean intraoperative pain score in the Tears group of 1.43±1.31 was higher (
P
=.085) than the intraoperative score of 0.97±1.16 in the ketorolac group.

Conclusions:

Pre- and intraoperative treatment with Acular LS significantly reduces postoperative LASIK pain. [
J Refract Surg
. 2009;25:210–213.]
Evaluation of the Apparent Change in Posterior Corneal Power in Eyes With LASIK Using Orbscan II With Magnification Compensation
Authors: Cheng Arthur C.K. , Ho Thomas , Lau Silvania , Lam Dennis S.C. 
Published: September 2019

Purpose:
To develop a mathematical model for the assessment of the apparent posterior corneal curvature changes after myopic keratorefractive surgery with Orbscan (Bausch & Lomb) and to assess its accuracy with clinical data.

Methods:

Part 1: Postoperative and preoperative magnification ratio of the posterior corneal surface was calculated from a theoretical eye model. Changes of radius and power of the posterior corneal surface were estimated over a wide range of refractive corrections and preoperative anterior corneal power. Part 2: The measured radius of the posterior cornea by Orbscan II 3 months postoperatively was converted to a new value based on the mathematical model. Both the measured radius and corrected radius were compared with preoperative values using paired sample
t
test.

Results:

Myopic correction is associated with apparent steepening of the posterior curvature. The higher the amount of correction, the more the apparent difference. A statistically significant difference was noted between preoperative and measured postoperative radius of the posterior cornea (0.35±0.16 mm,
P
<.01). However, no significant difference was seen between preoperative and corrected postoperative radius of the posterior cornea (0.008±0.11 mm,
P
=.44).

Conclusions:

The change of corneal magnification induced by refractive correction partly explains the apparent steepening of the posterior corneal curvature. The mathematical model effectively compensates for the error in Orbscan II in the assessment of posterior corneal curvature after LASIK. [
J Refract Surg.
2009;25:221–228.]
Matrix-optical Representation of Currently Used Intraocular Lens Power Formulas
Authors: Haigis Wolfgang 
Published: September 2019

Purpose:
The formulas presently used to calculate the power of intraocular lenses (IOLs) are the SRK II, SRK/T, Holladay I, Hoffer Q, and Haigis. Apart from the empirical SRK II, these formulas are based on paraxial optics. With different notations and different algebraic forms, a comparison between formulas is difficult. Matrix techniques, on the other hand, have been successfully used in paraxial optics for many years, offering an elegant, simple, and straightforward way to characterize complex optical systems. The aim of this study, therefore, was to represent the current theoretical IOL formulas in matrix notation.

Methods:
The SRK/T, Holladay I, Hoffer Q, and Haigis formulas were analyzed, algebraically transformed, and expressed in matrix-optical notation in the form of translation and refraction matrices and the system matrix. An example calculation was carried out and compared to results from two commercial biometry instruments (Zeiss IOLMaster and Tomey AL-2000).

Results:
Although all formulas examined are based on thin lens optics in paraxial approximation, considerable differences exist in the interpretation and calculation of corneal power, axial length, and effective lens position as well as the manner in which individual IOLs are represented (“IOL constants”). All relations necessary for matrix-optical representation are given.

Conclusions:

The matrix-optical representation of the currently used IOL power formulas offers new insights into the calculation of IOLs and allows a deeper understanding of the advantages and drawbacks of each formula. [
J Refract Surg.
2009;25:229–234.]
Changes in Iridocorneal Angle Structure and Trabecular Pigmentation With STAAR Implantable Collamer Lens During 2 Years
Authors: Chung Tae-Young , Park Sung Chul , Lee Myoung Ok , Ahn Kyeon , Chung Eui-Sang 
Published: September 2019

Purpose:
To evaluate the changes in iridocorneal angle structure and trabecular pigmentation after implantation with the STAAR Implantable Collamer Lens (ICL), as potential risk factors of secondary glaucoma.

Methods:
An ICL was implanted in 48 eyes of 29 patients with high myopia. Angle opening distance (distance between trabecular meshwork and iris) measured at 500 µm from the scleral spur and trabecular-iris angle were assessed preoperatively and at 1, 6, 12, and 24 months postoperatively by ultrasound biomicroscopy, and trabecular pigmentation was evaluated preoperatively and at 1, 12, and 24 months postoperatively by standardized gonioscopic photography.

Results:

Mean follow-up was 33.2±7.3 months. One-month postoperative trabecular-iris angle and angle opening distance values were significantly smaller than preoperative values by 41.5% and 31.8%, respectively (
P
<.001), but no significant progressive changes were observed thereafter. The mean trabecular pigmentation of four quadrants did not change significantly during the first month after ICL implantation (
P
=.317), but significantly decreased at 1 and 2 years postoperatively compared with the preoperative value (
P
=.039 and .047, respectively). Intraocular pressure (IOP) remained stable in all eyes throughout follow-up except in one eye, which showed elevated IOP and significantly increased trabecular pigmentation requiring antiglaucoma medications.

Conclusions:

No ongoing narrowing of iridocorneal angle was noted after approximately 40% narrowing at 1 month postoperatively. There was no general increase in trabecular pigmentation or IOP over a mean follow-up of 33.2 months. Considering significant initial angle crowding and one eye with increased trabecular pigmentation and IOP, careful monitoring of iridocorneal angle and IOP is required during the early postoperative period, especially for 1 month. [
J Refract Surg
. 2009;25:251–258.]
Prophylaxis of Diffuse Lamellar Keratitis With Intraoperative Interface Steroids in LASIK
Authors: Ng Eugene Y.J. , Thinagaran Sashin , Kinsella Frank , O'Keefe Michael 
Published: September 2019

Purpose:
To investigate the safety and efficacy of intraoperative interface steroids for the prophylaxis of diffuse lamellar keratitis (DLK).

Methods:
Two centers analyzed 1210 consecutive procedures in a prospective interventional trial. Center A irrigated the lasered stromal bed with balanced salt solution (BSS), instilled a drop of preserved dexamethasone 0.1% suspension on the stromal bed, and replaced the corneal flap. Center B replaced the flap, inserted a multiple port cannula to irrigate the stromal interface with BSS, then introduced 0.5 mL preservative-free prednisolone sodium phosphate 0.5% solution into the stromal interface with another multiple port cannula. All LASIK procedures after a fixed date received intraoperative interface steroids. Consecutive procedures immediately before this date were used as controls.

Results:
Center A performed 405 intraoperative interface steroids procedures and contributed 405 controls. Center B performed 200 intraoperative interface steroids procedures and contributed 200 controls. Preoperative refraction and postoperative visual acuity were similar in control and intraoperative interface steroids groups. In center A, 5.7% (30% were stage II) and 2% (all only stage I) of controls and intraoperative interface steroid eyes, respectively, developed DLK; intraoperative interface steroids decreased the rate of DLK by 3.0 times (95% confidence interval: 1.3 to 6.8). In center B, 6.5% of controls developed DLK (15% were stage II); with intraoperative interface steroids, only 1 procedure (0.5%) developed DLK. In both centers, no bilateral DLK or DLK beyond stage I were noted when intraoperative interface steroids were used.

Conclusions:

Intraoperative interface steroids safely reduced the incidence and severity of DLK. [
J Refract Surg.
2009;25:306–311.]