bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydroepithelial Keratectomy in Rabbits with a Waterjet-based Instrument
Authors: Parolini Barbara , Turdiu Parid , Abelson Marc , Zarbin Marco , Gordon Eugene 
Published: April 2021

ABSTRACT
BACKGROUND: Corneal epithelial removal finds multiple applications in ophthalmic surgery (epithelial herpes infections, recurrent epithelial erosion, corneal ulcers and plaques, and intraoperative epithelial clouding). Photorefractive keratectomy is initiated by removal of the epithelium. Current techniques for epithelial removal are suboptimal. We studied the safety and effectiveness of a new technique, hydroepithelial keratectomy, performed with the HydroBrush keratome on live rabbits.
METHODS: Eighteen rabbits (18 eyes) underwent hydroepithelial keratectomy and 18 rabbits (18 eyes) underwent epithelial removal with a surgical blade (blade group). Twelve rabbits were euthanized immediately after the procedure. Twenty-four rabbits were followed for up to 120 hours after treatment. Ultrastructural analysis was performed with light and electron microscopy.
RESULTS: The hydroepithelial keratectomy group healed a mean 53 hours after treatment; the blade group healed a mean 78 hours after treatment. The HydroBrush keratome exposed the basement membrane and the basal cell membrane of the epithelium. The blade exposed patches of basement membrane, as well as stroma and cell debris.
CONCLUSIONS: Hydroepithelial keratectomy with the HydroBrush keratome is effective and safe. Wound healing after hydroepithelial keratectomy is faster than after blade removal. Unlike the blade, the HydroBrush keratome exposed a smooth surface, devoid of debris, with well-defined edges and round shape without hydration nor dehydration of the tissue. [J Refract Surg 1998;14:346-3561
Refractive versus Corneal Changes After Photorefracive Keratectomy for Astigmatism
Authors: Alpins Noel A , Tabin Geoffrey C , Adams Lorraine M , Aldred Geoffrey F , Kent David G , Taylor Hugh R 
Published: April 2021

ABSTRACT
PURPOSE: To define measures of assessing success and subsequent ways to improve excimer laser treatment of astigmatism.
METHODS: We studied 97 eyes of 79 patients, followed for 12 months, that underwent photorefractive keratectomy (PRK) for myopia and astigmatism with a VISX 20/20 excimer laser. Preoperative spherical equivalent refraction at the corneal plane was between -1.00 and -15.00 D. Mean preoperative refractive astigmatism at the spectacle plan was -2.17 ± 1.05 D (range, -1.25 to -6.00 D), which is -1.81 ± 0.86 D (range -1.04 to -4.97 D) when calculated at the corneal plane. All patients were examined before and after surgery; examination included refraction, keratometry, and topography measurement.
RESULTS: The success in treatment of astigmatism appeared measurably less than the treatment of sphere when analogous indices were used for assessment. Success in astigmatism surgery improved, as measured by all parameters, after an additional 20% was applied to astigmatism treatment magnitude indicated by the VISX computer algorithm. The sequential modes of treatment undercorrected astigmatism magnitude to a greater extent than elliptical, but equivalent success rates were present in view of the greater astigmatic changes attempted using the sequential mode. The elliptical mode tended to produce a greater undercorrection of associated sphere (p=0.313). Results measured by refraction showed a larger change than those measured by topography and keratometry.
CONCLUSION: During PRK with the VISX 20/20 laser, adjustment for undercorrection of astigmatism treatment achieves a fuller correction of astigmatism. When measuring astigmatic changes, results are different when comparing refractive astigmatism changes with corneal astigmatism changes measured by keratometry and topography. [J Refract Surg 1998;14:386-396]
Evaluation of Pentoxifylline in the Prevention of Haze after Photorefractive Keratectomy in the Rabbit
Authors: Francesconi Claudia M , Abad Juan Carlos , Lim Jonathan E , Talamo Jonathan H 
Published: April 2021

ABSTRACT
BACKGROUND: Pentoxifylline (PTX) is a methylxanthine derivative that, besides its hemorrheologic properties, possesses multiple physiologic effects at the cellular level. It has been used in keloid prevention due to its ability to inhibit the secretion of collagen and glycosaminoglycans from activated fibroblasts.
METHODS: Ten New Zealand White (NZW) rabbits underwent a -7.00 diopters, 6.0 mm diameter photorefractive keratectomy after laser ablation of the epithelium with a VISX 20/20 excimer laser. The bare stroma was stained with fresh 0.5% dichlorotriazinyl aminofluorescein (DTAF). The procedure was performed on both eyes, 4 days apart. One eye received 1% Pentoxifylline qid and the other balanced salt solution qid as a control for 4 weeks, starting the same day of surgery. Two masked observers graded the amount of haze at 2, 4, 6, and 8 weeks after surgery using slit-lamp biomicroscopy. Three rabbits were sacrificed at 2 and 4 weeks followed by two rabbits at 6 and 8 weeks. The area between the DTAF-stained collagen to the base of the epithelium was measured using a digital image analyzer.
RESULTS: There was no statistically significant difference in the amount of haze either by slit-lamp microscopy or by histological analysis between the pentoxifylline-treated eyes and the controls at any time interval (Student's f-test: 0.16 to 0.92)
CONCLUSION: Pentoxifylline did not seem to affect haze formation in a PRK rabbit model. As no signs of toxicity were observed, further studies might examine higher concentrations or dose frequencies. [J Refract Surg 1998;14:567-570]
Photorefractive Keratectomy for -1.25 to -25.00 Diopters of Myopia
Authors: Pietilä Juhani , Mäkinen Petri , Pajari Seppo , Uusitalo Hannu 
Published: April 2021

ABSTRACT
BACKGROUND: We evaluated prospectively the efficacy, predictability, stability, and safety of photorefractive keratectomy (PRK) for myopia.
METHODS: Three hundred sixty-nine eyes of 257 patients were treated with an Aesculap-Meditec MEL 60 excimer laser. Treated eyes were divided into 3 groups: low myopes (-1.25 to -6.00 D), 226 eyes; medium myopes (-6.10 to -10.00 D), 104 eyes; high myopes (-10.10 to -25.00 D), 39 eyes. Follow-up at 12 months was available for 348 eyes (94%).
RESULTS: One year after surgery the number of eyes within ±1.00 D of emmetropia was 182 (86.7%) for low myopes, 43 (40.5%) for medium myopes, and 12 (30.8%) for high myopes. Values for ±0.50 D were low: 142 (67.6%), medium: 29 (29.3%), and high: 9 (23.1%). Three eyes with low myopia (1.4%) and 5 eyes with medium myopia (5.1%) lost 2 or more lines of spectacle-corrected visual acuity. None of the high myopes lost 2 or more lines. Uncorrected visual acuity of 20/20 or better was achieved in 82 eyes (39%) with low myopia; 20/40 or better was achieved in 183 eyes (87.1%). Five eyes (5.1%) of medium myopes achieved 20/20 or better; 52 eyes (52.5%) with medium myopia achieved 20/40 or better. Zero eyes with high myopia acheived 20/20 or better; 11 eyes (28.8%) achieved 20/40 or better.
CONCLUSION: Photorefractive keratectomy proved to be an effective method to correct myopia up to -6.00 D. For myopia greater than -6.00 D, good results were achieved in most eyes when myopia was less than -10.00 D, but efficacy and predictability decrease. To avoid systematic undercorrection, slight overcorrection must be attempted with the Aesculap-Meditec MEL 60 excimer laser for the treatment of myopia. [J Refract Surg 1998;14:615-622]
Evaluation of Increased Aqueous Outflow After Radial Keratotomy in Enucleated Bovine Eyes
Authors: Perez Edward P , Weinreb Seth , Blanco Ernesto , Miller David 
Published: April 2021

ABSTRACT
PURPOSE: We studied the efficacy of using radial keratotomy incisions as a surgical method of increasing outflow facility in enucleated bovine eyes.
METHODS: Each freshly enucleated bovine eye (n=23) was cannulated to a system measuring the rate of flow into the eyes. Preoperatively, corneal thickness measurements were determined for all treated eyes. Radial keratotomy was performed in 13 eyes and a control set of eyes (n=10) had no surgical manipulation. The intraocular pressure was set at 16.9mm Hg. A clear zone of 10 mm was used for each eye with the incision depth set at 100% of the pachymetric reading. One set of experimental eyes had incisions that remained in the clear cornea, and the other set had incisions that reached 2 mm beyond the limfaus into sclera. Preoperative outflow measurements were performed on each eye. Postoperative measurements were made after 10 incisions and 20 incisions. All eyes were checked for perforation after surgery and discarded if a perforation was found.
RESULTS: No eye included in the analysis was perforated. The preoperative (baseline) total flow rate was 27.90 ± 3.72 µ 1/min at 16.9 mmHg. The flow rate increased by 23.5% (over baseline) with 20 radial keratotomy incisions. A paired i-test was used to statistically compare the outflow measurements before radial keratotomy and after the first and second set of radial incisions. The increases in flow were found to be statistically significant (P<005) for both 10 and 20 radial incisions.
CONCLUSION: Assuming the flow measurements (flow rate) in these experiments parallel outflow facility, radial keratotomy increases the outflow facility in enucleated bovine eyes. [J Refract Surg 1998;14:641-645]
Corneal Sensitivity and Some Properties of the Tear Film After Laser in situ Keratomileusis
Authors: Patel Sudi , Pérez-Santonja Juan J , Alió Jorge L , Murphy Paul J 
Published: April 2021

ABSTRACT
PURPOSE: To investigate central corneal sensitivity, lipid layer structure of the precorneal tear film, and tear volume after laser in situ keratomileusis (LASIK).
METHODS: Central corneal sensitivity was measured using the Non-Contact Corneal Aesthesiometer. The aesthesiometer was mounted on a slit lamp and an airpulse of controlled pressure was directed onto the cornea. When central corneal sensitivity was reduced, a higher air pulse pressure was required to stimulate the cornea. The final central corneal sensitivity threshold measured was recorded in millibars. Tear lipid layer structure was assessed by optical interferometry and classified according to appearance using the Keeler Tearscope. Tear volume was measured using the phenol red cotton thread test. Subjects were recruited from a group of patients after LASEK who had experienced no complications (n=22). The average postoperative time was 14 weeks and measurements were taken on one eye. In bilateral cases, measurements were recorded from the right eye only. Average attempted correction was -6.30 D (range, -2 to -11 D). Age-matched controls were later recruited for central corneal sensitivity threshold (n=24). A second group of age-matched controls were recruited for tear volume and lipid layer structure (n=24).
RESULTS: The median (range) was 1.1 mbars (0.2 to 4.3 mbars) after LASEK and 0.58 mbars (0.20 to 1.3 mbars) in the controls; the difference was statistically significant (P = .043). The lipid layer of the tear film tended to be thinner in eyes after LASEK compared with controls (P = .032). The mean (± SD) tear volume was 16.9 ± 8.3 mm after LASEK and 19.8 ± 7.1 mm in controls. This difference was not statistically significant (P = .492).
CONCLUSION: At 14 weeks postoperatively, central corneal sensitivity was below normal levels and the tear lipid layer was thinner. The poorer quality lipid layer may predispose to symptoms of dry eye after LASEK. [J Refract Surg 2001;17:17-24]
Treatment of Progressive or Recurrent Epithelial Ingrowth With Ethanol Following Laser in situ Keratomileusis
Authors: Haw Weldon W , Manche Edward E 
Published: April 2021

ABSTRACT
PURPOSE: To evaluate the use of ethanol in the treatment of progressive or recurrent epithelial ingrowth following laser in situ keratomileusis (LASIK).
METHODS: Four eyes of four patients with aggressive epithelial ingrowth following LASIK underwent epithelial ingrowth removal with 50% ethanol. Aggressive epithelial ingrowth was defined as, 1) progressive enlargement on serial examination with an area of ingrowth involving at least 30% of the flap surface area, 2) epithelial ingrowth associated with stromal melting as evidence on clinical or topographic examination, or 3) recurrent epithelial ingrowth in the same area following previous removal.
RESULTS: Epithelial ingrowth was removed successfully in all eyes. No eye lost best spectaclecorrected visual acuity. One eye with multiple risk factors for failure experienced nonprogressive recurrence. No eyes required reoperation for recurrent epithelial ingrowth. No eyes experienced progression of stromal melt. Regularization of corneal topography was observed in an eye with preoperative stromal melting. The only complication was a tendency for the development of diffuse lamellar keratitis. Two eyes (50%) experienced diffuse lamellar keratitis following epithelial ingrowth removal with ethanol, which resolved completely with topical corticosteroids.
CONCLUSION: Ethanol may be a useful adjunct in the treatment of aggressive or recurrent epithelial ingrowth following LASIK. Cautious use with the lowest concentration of ethanol may prove useful in these difficult epithelial ingrowth cases. Randomized and prospective studies are recommended to evaluate our experience. [J Refract Surg 2001;17:63-68]
Non-invasive Measurement of Corneal Hydration
Authors: March Wayne F , Bauer Noel J C 
Published: April 2021

ABSTRACT
PURPOSE: To investigate the feasibility of a confocal Raman spectroscopic technique for the noncontact assessment of corneal hydration in vivo in two legally blind subjects.
METHODS: A laser beam (632.8 nm; 15 mJ) was maintained on the cornea using a microscope objective lens (25x magnification, NA=0.5, /=10 mm) both for focusing the incident light as well as collecting the Raman backscattered light, in a 180° backseat· ter configuration. An optical fiber, acting as the confocal pinhole for elimination of light from outof-focus places, was coupled to a spectrometer that dispersed the collected light onto a sensitive arraydetector for rapid spectral data acquisition over a range from 2890 to 3590 cm1. Raman spectra were recorded from the anterior 100 to 150 µta of the cornea over a period of time before and after topical application of a mild dehydrating solution. The ratio between the amplitudes of the signals at 3400 cm^sup -1^ (OH- vibrational mode of water) and 2940 cm^sup -1^ (CH-vibrational mode of proteins) was used as a measure of corneal hydration.
RESULTS: High signal-to-noise ratio (SNR 25) Raman spectra were obtained from the human corneas using 15 m J of laser light energy. Qualitative changes in the hydration of the anterior-most part of the corneas could be observed as a result of the dehydrating agent.
CONCLUSION: Confocal Raman spectroscopy could potentially be applied clinically as a noncontact tool for the assessment of corneal hydration in vivo. [J Refract Surg 2001;17(suppl):S205-S210]
Reduction of Hyperopia Associated With Manual Excision of Salzmann's Nodular Degeneration
Authors: Oster John G , Steinert Roger F , Hogan R Nick 
Published: April 2021

ABSTRACT
PURPOSE: Removing central corneal pathology often leads to a hyperopic shift secondary to corneal flattening. A myopic shift, or reduction in hyperopia, would be expected after removal of peripheral corneal pathology with central corneal steepening. This case illustrates the refractive changes induced by Salzmann's nodular degeneration and the myopic shift associated with their excision.
METHODS: A 53-year-old female presented with a slowly progressive increase in hyperopia. Vision in the right eye was 20/40 with a refraction of +10.00 -4.00 x 90°. Vision in the left eye was 20/30 with a refraction of +5.75 -2.00 x 105°. Both corneas exhibited nodular subepithelial opacities in the midperiphery. A superficial keratectomy was performed on each eye, 1 year apart.
RESULTS: Twelve days postoperatively, uncorrected visual acuity in the right eye was 20/25, and 20/20 with a refraction of -0.75 -0.50 x 31°, 6 months later. Six days postoperatively, uncorrected visual acuity in the left eye was 20/40, and 20/30 with a refraction of -1.25 D, 1 month later.
CONCLUSION: Superficial keratectomy provides a means of restoring the original corneal contour, especially when the pathology is easily dissected firom Bowman's layer. The surgeon should investigate the refractive status prior to the development of the nodules and be aware of the possible refractive change upon removal of the pathology. [J Refract Surg 2001;1 7:466-469]
Laser in situ Keratomileusis in Children 8 to 15 Years Old
Authors: Nassaralla Belquiz R A , Nassaralla João J 
Published: April 2021

ABSTRACT
PURPOSE: To determine the safety, efficacy, predictability, and stability of laser in situ keratomileusis (LASIK) to correct high myopia or high myopic astigmatism in patients with high anisometropia in whom conventional treatments have failed.
METHODS: Nine eyes of nine patients, three boys and six girls with high anisometropia (>3.50 D), were included in this study. Patient age was 8 to 15 years. Minimum follow-up was 12 months. All patients were treated with the Chiron Technolas 217 excimer laser.
RESULTS: Three months after LASIK, uncorrected visual acuity improved by at least five Snellen lines in all eyes. Three eyes (33.3%) were 20/40 or better without correction. Due to dense amblyopia, no eye had uncorrected visual acuity of 20/20 or better. The mean spherical equivalent refraction decreased from -7.66 to -0.22 D, and mean preoperative astigmatism decreased from -3.11 to -0.69 D. Eight eyes (88.8%) were within ±1.00 D of emmetropia. Two eyes (22.2%) were within ±0.50 D of the desired outcome. All patients were able to function binocularly.
CONCLUSION: In this study of selected older children, LASIK was a safe and effective option for the correction of high anisometropia and for improved binocularity, when conventional therapies had failed. Further study is necessary to determine the long-term refractive stability in these young patients. [J Refract Surg 2001;17:519-524]
Removal of Corneal Foreign Bodies Following Laser in situ Keratomileusis
Authors: Porges Yair , Landau David , Douieb Joseph , Levinger Samuel 
Published: April 2021

ABSTRACT
PURPOSE: To report the outcome of uncomplicated removal of corneal foreign bodies in patients who previously underwent laser in situ keratomileusis (LASIK).
METHODS: Nine eyes of eight patients presented with corneal foreign bodies after LASIK.
RESULTS: In three patients, diagnosis of corneal foreign bodies was delayed due to reduced pain and symptoms. Removal of foreign bodies was performed with no flap-related complications. Corneal wound healing was normal. Final visual acuity was not decreased.
CONCLUSION: Corneal foreign bodies can be removed safely and effectively from corneas after LASIK. [J Refract Surg 2001;17:559-560]
Laser in situ Keratomileusis for Hyperopia and Hyperopic Astigmatism With the Nidek EC-5000 Excimer Laser
Authors: Pineda-Fernández Angel , Rueda Lizbeth , Huang David , Nur Jorge , Jaramillo Jorge 
Published: April 2021

ABSTRACT
PURPOSE: We evaluated the efficacy, predictability, stability, and safety of laser in situ keratomileusis (LAStK) for hyperopia and hyperopic astigmatism.
METHODS: A retrospective study was performed for 92 eyes of 62 consecutive patients to evaluate uncorrected (UCVA) and best spectacle-corrected visual acuity (BSCVA) and manifest refraction before and 3 and 6 months after IASIK (Moria LSKONE microkeratome, Nidek EC-5000 excimer laser). Eyes were divided into groups: Group 1 (low hyperopia) for spherical correction of +1.00 to +3.00 D (22 eyes), Group 2 (low hyperopic astigmatism) for toric correction with spherical equivalent refraction of +1.00 to +3.00 D (18 eyes), Group 3 (moderate hyperopia) for spherical correction of +3.25 to +6.00 D (10 eyes), and Group 4 (moderate hyperopic astigmatism) for toric correction with spherical equivalent refraction between +3.25 and +6.00 D (18 eyes).
RESULTS: At 3 and 6 months after LASLK, 68 eyes (73.9%) were available for follow-up examination. Percentage of eyes with a spherical equivalent refraction within ?0.50 D of emmetropia for Group 1 was 54.5% (12 eyes); Group 2, 50% (9 eyes); Group 3, 40% (4 eyes), and Group 4, 38.8% (7 eyes). UCVA 2*20/20 in Group 1 was 14% and in Groups 2, 3, and 4, 0%. One eye (5.5%) lost two lines of BSCVA.
CONCLUSION: LASLK with the Moria LSK-ONE microkeratome and the Nidek EC-5000 excimer laser reduced low and moderate hyperopia and was within ?0.50 D of target outcome in approximately 50% of eyes. Undercorrection was evident in all groups. The procedure was safe. [?/ Refract Surg 2001;17:670-675]
Conductive Keratoplasty to Correct Hyperopic Astigmatism
Authors: Pallikaris Ioannis G , Naoumidi Tatiana L , Astyrakakis Nikos I 
Published: April 2021

ABSTRACT
PURPOSE: To evaluate the efficacy of conductive keratoplasty in the treatment of pre-existing and surgically induced hyperopic astigmatism.
METHODS: In this prospective, noncomparative case series, four eyes of four subjects, two female and two male (age 25 to 47 yr) were treated for hyperopia (up to +5.50 D) and hyperopic astigmatism (up to +5.75 D) with the Refractee ViewPoint conductive keratoplasty system. The follow-up period was 6 months. Uncorrected and spectaclecorrected visual acuity, manifest and cycloplegic refraction, and videokeratographs were obtained before and after surgery. We treated two patients who had already had LASDK, one of them with a decentered ablation and the other with flap striae, one patient after PRK, and one patient with keratoconus.
RESULTS: No complications were observed. No eye lost lines of spectacle-corrected visual acuity. All eyes showed improvement of uncorrected visual acuity of 3 or more lines. Videokeratographs demonstrated improved centration and reduction in keratometric power readings. Each eye was analyzed separately, including a comparative analysis of the proposed nomograms and quality of vision after surgery.
CONCLUSIONS: Conductive keratoplasty may be a minimally invasive solution for patients with irregular hyperopic astigmatism, offering improved quality of vision in instances of flap striae by tightening the central cornea. [J Refract Surg 2003;19:425-432]
Optic Nerve Head Blood Flow Using Scanning Laser Doppler Flowmetry After Laser in situ Keratomileusis
Authors: Ozdamar Akif , Ocakoglu Ozcan 
Published: April 2021

ABSTRACT
PURPOSE: To investigate ocular blood flow changes following laser in situ keratomileusis (LASIK) in myopic eyes.
METHODS: Seventeen eyes of ten myopic patients were included in the study. Mean age of the seven men and three women was 29.1±2.5 years. Mean spherical equivalent retraction was -7.70±2.52 D. LASEK was performed with the Hansatome microkeratome and Summit SVS Apex excimer laser. Optic nerve head blood flow was measured by using the Heidelberg Retinal Flowmeter preoperatively and postoperatively at 1 day, 1 week, and 1 month. Preoperative ocular blood flow data (blood flow, volume, velocity) were compared with postoperative data using variance analysis. Correlation analysis was performed for age of patients, suction time, and ocular blood flow data.
RESULTS: Mean suction time was 19±7 seconds. There was no significant correlation between suction time, age, and ocular blood flow. We found an increase in blood flow at the lamina cribrosa taken 1 day postoperatively (P=.04). Blood flow returned to preoperative values at the 1-week and 1-month measurements in the lamina cribrosa region. There was no significant change in ocular blood flow data in the neuroretinal rim except an increase in velocity at the lower nasal quadrant on postoperative day 1 (P=.03).
CONCLUSIONS: LASIK caused a temporary increase in blood flow at the lamina cribrosa region of the optical nerve head in healthy myopic eyes. The increase in blood flow may suggest a compensatory change for maintaining blood flow in the ocular nerve head following LASIK-induced ischemia. [J Refract Surg 2003;19:433-4371