bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photorefractive Keratectomy for Myopia of 6 to 12 Diopters
Authors: Chan Wing-Kwong , Heng Wee Jin , Tseng Peter , Balakrishnan Vivian , Chan Tat Keong , Low Cze Hong 
Published: April 2021

ABSTRACT
To conduct a prospective, nonrandomized clinical trial to assess the efficacy, stability and safety of the use of excimer laser photorefractive keratectomy (PRK) to correct myopia of greater than -6.00 diopters (D) in Singapore.
Two hundred thirty-three eyes of 176 patients with a mean preoperative spherical equivalent refraction of -8.70 ± 2.30 D (range, -5.75 D to -18.13 D) underwent PRK with a 193nm ArF excimer laser (ExciMed, Summit) for myopic corrections of between -6.20 D and -11.90 D. The first 66 of 233 eyes that reached at least 1 year of postoperative follow up are reported.
One year postoperatively, the mean manifest spherical equivalent refraction was -1.50 D ± 1.90 D (range -6.25 D to +3.25 D); 34% of eyes were within ± 1.00 D of attempted correction; uncorrected visual acuity was 20/40 or better in 75% of eyes. No eyes lost two or more Snellen lines of spectacle corrected visual acuity. Central corneal haze was mild in 20% of eyes and moderate in 3% of eyes. Five eyes developed ocular hypertension that subsequently resolved with treatment.
Excimer laser PRK is reasonably effective and safe in the treatment of -6.00 D to -12.00 D of myopia. However, it is less accurate than PRK in eyes with low to moderate myopia and is more likely to result in significant corneal haze. [J Refract Surg. 1995;11(suppl.):S286-S292.]
Automatic Eye Tracker for Excimer Laser Photorefractive Keratectomy
Authors: Gobbi Pier Giorgio , Carones Francesco , Brancato Rosario , Carena Marco , Fortini Alberto , Scagliotti Franco , Morico Alessandro , Venturi Elisabetta 
Published: April 2021

ABSTRACT
Acute overlapping of successive laser pulses onto the cornea during photorefractive keratectomy (PRK) is important to avoid refractive distortions. Most excimer laser systems performing corneal ablation lack control of the patient's eye movements and they cannot track the target corneal zone.
We developed an eye-tracker based on television monitoring of the pupil and on automatic electromechanical deflection of the laser turning mirror, and we applied it to the ExciMed UV200 ArF work station (Summit Technology, Inc., Waltham, Mass.). Basic components are a black and white CCD camera and two fast stepping motors. The circuitry for target discrimination and tracking, and the optical imaging system are designed specifically. The tracker assembly does not interfere with the laser beam path nor with the operator's observation.

Tracking of the pupil has been successfully achieved on different color irides, with an accuracy better than 0.1 mm in a 6 × 6 mm
p 2
tracking field. Response time is less than 100 me. Recordings of eye movements during PRK are presented. Tracking ablations have been performed on moving test eyeballs with plastic corneas.

The proposed automatic system appears to be a reliable and effective method for the compensation of patient eye movements appears to be a reliable and effective method during PRK procedures. [J Refract Surg.1995; 11 (suppl.):S337-S342.]
Holmium: YAG Laser to Treat Astigmatism Associated With Myopia or Hyperopia
Authors: Cherry Paul M H 
Published: April 2021

ABSTRACT
The Summit Technology, Inc. (Waltham, Mass.) holmium:YAG laser was used to treat astigmatism in 31 myopic and 8 hyperopic eyes. There was slow but continuing regression of effect even 1 year after treatment. This regression was particularly seen in hyperopic astigmatism, larger amounts of myopic astigmatism, and younger patients. In some cases keratometry readings returned to their pretreatment values. Males and females had similar results. The mean myopic shift in 9 myopic astigmatism eyes at 9-month follow up was 1 D. [J Refract Surg. 1995;11(suppl.):S349-S357.]
Corticosteroid Suppression of TraumaInduced Hyaluronan in Rabbit Cornea and Aqueous
Authors: Molander Nils , Ehinger Berndt , Stenevi Ulf , Lindquist Ulf , Lind Maj-Lis 
Published: April 2021

ABSTRACT
BACKGROUND: Corneal and aqueous hyaluronan have recently been shown to react in response to several different types of trauma, including cataract surgery. In order to find ways to influence the reaction, we have evaluated the effect of topical dexamethasone (Isopto-Maxidex®, Alcon Universal Ltd, Fort Worth, Tex) or indomethacin (Confortid®, Dumex Ltd, Copenhagen, Denmark) on the postoperative hyaluronan concentration in rabbit cornea and aqueous after extracapsular lens extraction.
METHODS: The drugs were administered as topical eye drops three times daily. The hyaluronan concentration in rabbit cornea and aqueous after extracapsular lens extraction was measured with a radioligand assay.
RESULTS: Dexamethasone treatment (1 mg/mL) significantly suppressed the increase in corneal hyaluronan seen after extracapsular lens extraction, 2 (p≤0.0022) and 3 weeks (p≤0.0002) after surgery, while indomethacin did not induce any significant difference at 2 weeks. When the dexamethasone concentration was lowered to 0.1 and 0.2 mg/mL, there was still a significant decrease (p≤0.009) in hyaluronan concentration, but at lower concentrations of dexamethasone (0.01 and 0.02 mg/ mL), no significant decrease was seen. The increase in aqueous hyaluronan concentration seen 2 days after surgery in untreated eyes was significantly lowered by both dexamethasone (p≤O.0076) and indomethacin (p≤0.036).
CONCLUSIONS: Dexamethasone lowers reactive corneal and aqueous hyaluronan concentration in vivo after extracapsular lens extraction. [J Refract Surg. 1995;11:260-266.]
Comparison of Histologic Findings in Wound Healing of Rabbit Scleral Homografts With Fibrin Glue (Tisseel®) and Suture Material
Authors: Lee Kyeong Hee , Kim Man Soo , Hahn Tae Won , Kim Jae Ho 
Published: April 2021

ABSTRACT
BACKGROUND: This study was performed to observe the histological differences of scleral homografts with fibrin glue and with suture material and to evaluate the effect of fibrin glue on wound healing as a fixation method in rabbits. Rabbits were divided into two groups: a suture group, using 10-0 nylon sutures, and a fibrin glue group, using Tisseel®.
METHODS: At 1, 7, 14, 30, and 90 days after scleral graft, the tissues of grafted rabbit scleras were examined under light microscope after staining with hematoxylin-eosin.
RESULTS: In the scleral homograft, fibrin glue induced hemostasis and inhibited the inflammatory process. At 7 days, aggregation of fibroblasts was more prominent at the fibrin glue site than at the suture site. At 14 days, a larger number of fibroblasts and more collagen fibril bundles were seen at the interspace between donor and recipient scleras in the fibrin glue group than in the suture group. At 1 month, more condensed collagen was seen in the fibrin glue group. At 3 months, the interspace between graft and recipient tissues showed complete wound healing with well-arranged, condensed collagen fibril bundles in the fibrin glue group.
CONCLUSION: These findings suggest that fibrin glue may promote hemostasis as well as collagen formation by fibroblasts and inhibit the inflammatory process in scleral homografts. [J Refract Surg. 1995;11:397-401.]
Laser Epithelial Keratomileusis for Myopia With the Autonomous Laser
Authors: Rouweyha Rajy M , Chuang Alice Z , Mitra Shrabanee , Phillips Chris B , Yee Richard W 
Published: April 2021

ABSTRACT
PURPOSE: To describe the refractive outcome, objective clinical data, and subjective patient experiences after laser epithelial keratomileusis (LASEK) at 1, 3, and 6 months after surgery.
METHODS: This was a retrospective, nonrandomized, comparative study of 58 LASEK-treated eyes (36 patients) with myopia (with and without astigmatism) between -1.50 and -14.75 D (mean -7.80 ± 2.90 D, median -7.90 D). Refractive surgery was performed using the Alcon Summit Autonomous LADAR Vision excimer laser. Manifest refraction, best-spectacle and uncorrected Snellen visual acuity, stability of refraction, and corneal haze were evaluated before surgery and up to 6 months after surgery. A group of randomly selected LASIK-treated eyes were compared at each time point.
RESULTS: Patients who opted for monovision (n=12) were excluded. In the emmetropia targeted eyes (n=46), 45%, 83%, 85%, and 89% achieved 20/40 or better uncorrected Snellen visual acuity (UCVA) at 1 day, 1 week, 2 weeks, and 1 month respectively. At 6 months, 73% (n=28) of eyes treated achieved UCVA 20/20 with 97% achieving 20/40 or better (mean, -0.51 D). At 3 and 6 months, 71% (n=46) and 68% (n=28) were within ±0.50 D of emmetropia. The percentage of eyes that achieved UCVA 20/40 or better at 6 months was 97% (n=28). Visually significant corneal haze was evident in two LASEK-treated patients (four eyes) at 6 months. No eyes lost two or more lines of best spectacle-corrected Snellen visual acuity.
CONCLUSIONS: Preliminary data suggest that LASEK appears to be a safe, effective, and comparable alternative to LASIK, even for higher amounts of myopia. A prospective, randomized clinical trial is needed to better define the role of LASEK as it compares to other refractive procedures, specifically LASIK and PRK. [J Refract Surg 2002;18:217-224]
Changes in Mesopic Vision After Photorefractive Keratectomy for Myopia
Authors: Nagy Zoltán Z , Munkácsy Györgyi , Krueger Ronald R 
Published: April 2021

ABSTRACT
PURPOSE: To evaluate the mesopic functions of excimer laser treated eyes with different treatment diameters and different laser beam delivery systems.
METHODS: In Group 1, 38 eyes were treated with the Aesculap Meditec MEL 60 ArF scanning laser beam excimer laser. The treatment diameter was 5.0 mm. In Group 2, 38 eyes were treated with the Aesculap Meditec MEL 70^sub G-Scap^ flying spot excimer laser; the chosen treatment diameter was 6.5 mm. In Group 3, there were 38 eyes with no treatment; vision was corrected only with spectacles (control group). All eyes had 20/20 best spectacle-corrected visual acuity before surgery, as did the control group. Measurements were carried out preoperatively and at 12 months following surgery. All eyes exhibited normal corneal wound healing, and subepithelial haze was <0.5 according to Hanna's scale. Mesopic functions (mesopic vision and glare sensitivity) were tested with the Mesoptometer II.
RESULTS: The average preoperative refractive error in Group 1 was -3.40 D; in Group 2, -3.38 D; in Group 3, -3.44 D. In Group 1, 34% of the treated eyes met the night driving requirements (recognition at 1:5 contrast level), whereas in Group 2, 85%, and in Group 3, 95% of the eyes fulfilled this criteria. When contrast vision was tested under glare conditions in Group 1, 31.6%; in Group 2, 80%; and in Group 3, 94.7% of the eyes identified the target orientation (Landolt ring) at contrast level 1:5.
CONCLUSIONS: The unoperated spectacle wearers had better results in all tested functions. The larger 6.5-mm treatment diameter with the use of the flying spot laser beam delivery system resulted in better mesopic function and contrast vision under mesopic conditions than the smaller 5.0-mm diameter. [J Refract Surg 2002;18:249-252]
Pseudo-accommodation With Intraocular Lenses Implanted in the Bag
Authors: Altan-Yaycioglu Rana , Gözüm Nilüfer , Gücükoglu Ahmet 
Published: April 2021

ABSTRACT
PURPOSE: To evaluate the accommodation potential in eyes after intraocular lens in-the-bag implantation.
METHODS: Fifty-one consecutive patiente were included in the study. Group 1 included 26 eyes that had phacoemulsification with continuous curvilinear capsulorhexis and in-the-bag implanted foldable IOL. Twenty-five eyes in Group 2 had capsulotomy with extracapsular cataract extraction and were implanted with polymethylmethacrylate IOL. Time elapsed from surgery was at least 6 months. There was no significant difference for age or gender between groups (P>.05). We measured accommodation amplitude and depth of the anterior chamber at distance and near fixation with an ultrasonic biometry device. The results were compared using the unpaired Student t-test.
RESULTS: The anterior chamber depths while fixating at a distant object were not significantly different between groups (P>.05), however, at near the difference was statistically significant (P=.008). The change in depths between far and near fixation was significantly different (P=.002) and was more pronounced in the the capsulorhexis group (P<.001). The accommodation amplitudes in this group were significantly greater than in the capsulotomy group (P=.025).
CONCLUSION: Patients who had uncomplicated small incision phacoemulsification surgery with continuous curvilinear capsulorhexis and in-the-bag implanted lens seemed to preserve some pseudo-accommodation after surgery. [J Refract Surg 2002;18:271-275]
Antioxidant Activity of Tear Fluid and Antioxidant Therapy in Myopic Patients After Laser in situ Keratomileusis
Authors: Smirennaia Elena , Kourenkov Vyacheslav , Chesnokova Natalya B , Kuznetsova Tatyana P 
Published: April 2021

ABSTRACT
PURPOSE: To study the antioxidant activity of the tear fluid after laser in situ keratomileusis (LASIK).
METHODS: Antioxidant activity of the tear fluid was investigated in 12 eyes of seven patients with myopia who underwent LASIK. All patients were treated with the Nidek EC-5000 excimer laser using the Chiron Vision Hansatome HT-230 microkeratome. The hemoluminescence method for assessment of antioxidant activity of tear fluid was used.
RESULTS: Increase in antioxidant activity of tear fluid was found in 50% of eyes and decrease was found in 25% of eyes on day 4 after surgery. In 25% of eyes, antioxidant activity did not change. Parameters of antioxidant activity returned approximately to preoperative levels in 75% of eyes on the 7th day. In eyes with increased antioxidant activity on the 7th day, signs of epitheliopathy and light dystrophic corneal flap changes were found. Topical use of antioxidants led to clinical improvement.
CONCLUSIONS: In eyes with epithelial or corneal flap problems after LASIK, we recommend 2-week antioxidant therapy for cornea protection from oxygen-derived free radicals. [J Refract Surg 2002;18(suppl):S364-S365]
Refractive Lens Exchange With an Array Multifocal Intraocular Lens
Authors: Dick H Burkhard , Gross Susanne , Tehrani Mana , Eisenmann Dieter , Pfeiffer Norbert 
Published: April 2021

ABSTRACT
PURPOSE: To prospectively evaluate safety, efficacy, predictability, stability, complications, and patient satisfaction after refractive lens exchange (clear lens extraction) followed by posterior chamber implantation of a multifocal intraocular lens (IOL).
METHODS: Fifty eyes of 25 patients (mean age 51 years, range 44 to 62 years) with preoperative spherical equivalent refraction between -15.50 and +5.75 D and cylinder between 0 and 1.50 D underwent bilateral implantation of a zonal progressive multifocal IOL (Array, AMO).
RESULTS: Eyes were divided into group A (n=24; myopia, average preoperative spherical equivalent refraction -7.11 ± 3.25 D (-1.75 to -15.50 D), and group B (n=26; hyperopia, average preoperative spherical equivalent refraction +3.04 ± 1.04 D). Follow-up was 6 months in ail eyes. Postoperatively, all eyes of both groups were within ±1.00 D of target refraction. No eye in group A and three eyes in group B sustained a loss of one line of BSCVA, Forty-seven eyes (94%) remained unchanged or gained one or more lines of their preoperative BSCVA In all eyes, postoperative UCVA was 20/40 or better. When compared to preoperative, uncorrected near visual acuity improved (statistically significant). All patients achieved uncorrected binocular visual acuity of 20/30 and J4 or better. Patient satisfaction was extremely high; no intraor postoperative complications were reported.
CONCLUSION: Six-month results of implantation of the AMO Array multifocal IOL for refractive lens exchange demonstrated safety, efficacy, and predictability in correcting high ametropia and significant improvement of uncorrected near and distance visual acuity. [J Refract Surg 2002;18:509-518]
Photorefractive Keratectomy Using the Meditec MEL 70 G-scan Laser for Hyperopia and Hyperopic Astigmatism
Authors: Nagy Zoltán Z , Munkácsy Györgyi , Popper Mónika 
Published: April 2021

ABSTRACT
PURPOSE: To evaluate the results of photorefractive keratectomy (PRK) using Gaussian flying spot technology in the treatment of hyperopia and hyperopic astigmatism.
METHODS: Two hundred eyes were evaluated with 12-month follow-up. An Asclepion-Meditec MEL 70 G-scan flying spot ArF excimer laser with a Gaussian scanner was used (6.0-mm treatment zone and 9.0-mm transition zone). Eyes were divided into four groups: Group 1 (spherical hyperopia up to +3.50 D and astigmatism lees than 1.00 D, n=62); Group 2 (hyperopia up to 4-3.50 D and astigmatism of 1.00 D or more, n=44); Group 3 (hyperopia greater than +3.50 D and astigmatism less than 1.00 D, n=56); and Group 4 (hyperopia greater than +3.50 D and astigmatism of 1.00 D or more, n=38).
RESULTS: In Group 1, 82.2% (51/62 eyes) were within ±0.50 D of target refraction; 88.7% (55/62 eyes) had 20/20 or better uncorrected visual acuity; 1.6% (1/62 eye) lost two or more lines, 3.2% (2/62 eyes) gained two or more lines of spectacle-corrected visual acuity. In Group 2, 68.1% (30/44 eyes) were within ±0.50 D; 77.2% (34/44 eyes) had 20/20 or better uncorrected visual acuity; 9.1% (4/44 eyes) lost two or more lines of spectacle-corrected visual acuity. In Group 3, 76.8% (43/56 eyes) were within ±0.50 D; 78.6% (44/56 eyes) had 20/20 or better uncorrected visual acuity; 5.4% (3/56 eyes) lost two or more lines of spectacle-corrected visual acuity. In Group 4, 42% (16/38 eyes) were within ±0.50 D; 60.5% (23/38 eyes) had 20/20 or better uncorrected visual acuity; 15.8% (6/38 eyes) lost two or more Snellen lines.
CONCLUSION: PRK with the flying spot Méditée MEL 70 G-scan was most safe and effective for low hyperopia. [J Refract Surg 2002;18:542-550]
Are All Aberrations Equal?
Authors: Applegate Raymond A , Sarver Edwin J , Khemsara Vic 
Published: April 2021

ABSTRACT
PURPOSE: To determine for a fixed RMS error (25 µm, over a 6-mm pupil) how each mode of the normalized Zernike polynomial (second through the fourth radial order) affects high and low contrast logMAR visual acuity.
METHODS: Three healthy volunteers served as subjects. CTView was used to generate optically aberrated logMAR charts. Accommodation was paralyzed and pupils dilated. The foveal achromatic axis of the eye was aligned to a 3-mm pupil and the eye was optimally refracted. Aberrated acuity charts were read until five letters were missed. Data were normalized for each subject to the acuity obtained by reading unaberrated charts and plotted as letters lost as a function of Zernike mode.

RESULTS: Defocus (Z
p 0
2
) decreased letter acuity more than astigmatism (Z
p 2
2
, Z^sup -2^
2
). Coma (Z
p 1
3
, Z^sup -1^
3
) decreased acuity more than trefoil (Z
p 3
3
, Z^sup -3^
3
). Spherical aberration (Z
p 0
4
) and secondary astigmatism (Z
p 2
42
, Z^sup -2^
4
) decreased acuity much more than quadrafoil (Z
p 4
4
, Z^sup -4^
4
).

CONCLUSIONS: 1. For an equal amount of RMS error not all coefficients of the Zernike polynomial induce equivalent losses in high and low contrast logMAR acuity. 2. Wavefront error concentrated near the center of the pyramid adversely affects visual acuity more than modes near the edge of the pyramid. 3. Large changes in chart appearance are not reflected in equally large decreases in visual performance (ie, subjects could correctly identify highly aberrated letters). 4. Interactions between modes complicate weighting each Zernike mode for visual impact. [J Refract Surg 2002;18:S556-S562]
Are Optical Aberrations During Accommodation a Significant Problem for Refractive Surgery?
Authors: Artal Pablo , Fernández Enrique J , Manzanera Silvestre 
Published: April 2021

ABSTRACT
PURPOSE: To study the limits to a perfect ideal customized wavefront correction due to the change of aberrations during accommodation.
METHODS. We measured the dynamic changes of ocular aberrations during accommodation in normal eyes with a real-time Hartmann-Shack wavefront sensor. Those results were used in computer simulations to predict the benefit of a perfect customized correction.
RESULTS: Due to the continuous changes of the aberrations over time, an ideal perfect static correction will not provide stable aberration-free optics. For example, when the eye accommodates to near objects, due to the changing aberrations, the eye will become aberrated again. An alternative correction using the aberration pattern for a slightly accommodated condition could provide a bettercorrection in a larger accommodative range, although at the cost of non-perfect correction for far vision.
CONCLUSIONS: Due to the dynamic nature of ocular optics, a static perfect correction, for instance performed in customized refractive surgery, would not remain perfect for every condition occurring during normal accommodation. [J Refract Surg 2002;18:S563-S566]
Wavefront and Topography: Keratome-induced Corneal Changes Demonstrate That Both Are Needed for Custom Ablation
Authors: Schwiegerling Jim , Snyder Robert W , Lee James H 
Published: April 2021

ABSTRACT
PURPOSE: To examine the effects of laser in situ keratomileusis (LeASIK) flap incision and healing on the shape of the cornea and the wavefront error of the eye.
METHODS: Four weeks prior to bilateral LASLK, study subjects had a flap cut using a keratome in one eye. The fellow eye remained untouched as a control. Corneal topography and wavefront errors were measured at 1 day, 1, and 4 weeks after the flap was created. After 4 weeks, the flap was lifted and LASLK was performed. The control eye also had LASLK at this time.
RESULTS: Differences in corneal shape and wavefront error consistent with a mild hyperopic shift were seen as a result of the keratome incision.
CONCLUSION: Cutting the flap in LASLK causes subtle changes to corneal shape and the optics of the eye that may affect customized treatments. Additional work is needed to quantify these changes so that their effect can be incorporated into future treatments. [J Refract Surg 2002; 18:S584-S588]
Wavefront-guided Photorefractive Keratectomy for Myopia and Myopic Astigmatism
Authors: Nagy Zoltán Z , Palágyi-Deák Ilona , Kelemen Edit , Kovács Andrea 
Published: April 2021

ABSTRACT
PURPOSE: To evaluate the results of wavefrontsupported customized ablation (WASCA) in eyes treated with photorefractive keratectomy (PRK) to correct spherical myopia and myopic astigmatism.
METHODS: One-hundred fifty eyes of 104 patients (mean age 33.4 ± 4.4 years) were included in the study. An Asclepion Shack-Hartmann wavefront aberrometer was used to assess lower and higher order refractive aberrations of eyes, and customized PRK treatments were carried out using the Asclepion-Meditec MEL 70 G-Scan excimer laser. Follow-up time was 6 months.
RESULTS: The mean preoperative spherical equivalent refraction was -4.02 ±- 1.04 D, and mean uncorrected visual acuity (UCVA) was 0.06 ± 0.02. Postoperatively, mean UCVA was 1.04 (better than 20/20), mean best spectacle-corrected visual acuity was 1.22 (20/16), and average spherical equivalent refraction was -0.12 D; 98.6% (148 of 150 eyes) were within ±0.50 D of intended refraction, and 100% were within ±1.00 D. Concerning safety, in 71.1% of eyes (107 of 150) BSCVA was the same as preoperative^, and in 8.2% (11 of 150) it increased by two or more Snellen lines. None of the eyes lost two or more lines of BSCVA. The root mean square value for higher order aberrations increased 1.4 times following PRK.
CONCLUSIONS: WASCA-guided PRK was efficacious, safe and predictable; BSCVA may be improved by the WASCA method compared to results achievable with a traditional PRK technique, in spite of an increase in the root mean square value for higher-order aberrations. [J Refract Surg 2002;18:S615-S619]