bluuebunny/crossref_metadata_2025 huggingface dataset:
Eight-year Follow-up of Photorefractive Keratectomy for Myopia
Authors: Pietilä Juhani , Mäkinen Petri , Pajari Tero , Suominen Sakari , Keski-Nisula Juho , Sipilä Kalle , Huhtala Anne , Uusitalo Hannu
Published: December 2019

ABSTRACT

PURPOSE: We evaluated 8-year results of excimer laser photorefractive keratectomy (PRK) for myopia in terms of stability and late complications.

METHODS: Ninety-two myopic eyes of 55 patients were treated with a single-step method using an Aesculap-Meditec MEL 60 excimer laser with a 5.0-mm ablation zone. Treated eyes were divided into three groups according to preoperative refraction: low myopes (≤-6.00 D), medium myopes (-6.10 to -10.00 D), and high myopes (>-10.00D).

RESULTS: Change in myopic regression stabilized in all myopia groups within 12 months, although a small myopic shift occurred up to 8 years after PRK. Mean change in refraction between 2 and 8 years was -0.42 ± 0.48 D for low myopes, -0.37 ± 0.34 D for medium myopes, and -0.41 ± 0.50 D for high myopes. The percentage of eyes within ±1.00 D of emmetropia 8 years after PRK was 78.3% in the low myopia group, 68.8% in the medium myopia group, and 57.1% in the high myopia group. One eye lost 2 lines of best spectacle-corrected visual acuity due to irregular astigmatism. In 13.0% of eyes, a residual trace corneal haze was observed, which had no effect on visual acuity. Apart from the loss of 2 lines of BSCVA in one eye, there were no other late complications during the study period.

CONCLUSIONS: The mean change in refraction between 2 and 8 years was less than -0.50 D, regardless of preoperative refraction, and may be attributed to natural age-related refractive change. The appearance of residual corneal haze after 8 years correlated with the amount of myopic correction. PRK was a safe and stable surgical procedure in this group of patients. [J Refract Surg 2004;20: 110-115]
Laser Subepithelial Keratomileusis for Myopia of -6 to -10 Diopters With Astigmatism With the MEL60 Laser
Authors: Bilgihan Kamil , Hondur Ahmet , Hasanreisoglu Berati
Published: December 2019

ABSTRACT

PURPOSE: To evaluate the efficacy, predictability, and safety of laser subepithelial keratomileusis (LASEK) for treatment of high myopia with astigmatism.

METHODS: LASEK was performed in 61 eyes of 36 consecutive patients with myopic spherical equivalent refraction of -6.00 to -10.00 D using the Aesculap-Meditec MEL60 excimer laser. Data were collected prospectively with a follow-up of 6 to 17 months. Main outcome measures recorded were UCVA, BSCVA, residual refractive error, corneal haze, and complications.

RESULTS: Ninety-six percent of eyes achieved 20/40 or better UCVA at 1 month. At 12 months, 64% of eyes achieved 20/20 and 92% achieved 20/40 or better UCVA. Two eyes lost 2 lines of BSCVA at 6 or 12 months. Accuracy of correction was ±0.50 D from emmetropia in 82% of eyes, and ±1.00 D in 90% at 12 months. No eye showed more than grade 1 haze. Grade 1 haze was observed in three eyes at 12 months. One patient had mild postoperative keratitis, which was successfully treated.

CONCLUSIONS: LASEK with the Aesculap-Meditec MEL60 excimer laser appeared to be safe, effective, and highly predictable in treating high myopia. [J Refract Surg 2004;20:121-126]
Diode Laser Thermal Keratoplasty for Hyperopia and Hyperopic Astigmatism in Patients Younger Than 40 Years
Authors: Berret Rudolf , Jean Benedikt , Bende Thomas
Published: December 2019

ABSTRACT

PURPOSE: We performed a prospective, nonrandomized investigation of contact continuous wave diode laser thermal keratoplasty (DTK) for correction of hyperopia and hyperopic astigmatism. The goal of surgery was not to achieve emmetropia but to investigate the refractive effect in patients younger than 40 years.

METHODS: Twenty eyes with spherical hyperopia (Group A) and 15 eyes with hyperopic astigmatism (Group B) were treated with two rings; treatment zone diameter of the inner ring was 6 or 7 mm. Each ring consisted of eight spots for hyperopia correction; for astigmatism correction four additional pairs of spots were applied around the flat corneal meridian.

RESULTS: Mean change in manifest spherical equivalent refraction 18 months postoperatively in Group A was 2.00 ± 0.90 D (Group B, 15 mo, 1.80 ± 0.60 D). Mean increase in keratometric power was 1.20 ± 0.60 D (1.30 ± 0.60 D). Mean refractive astigmatism reduction was 0.10 D (1.70 D). Mean paired differences per month for regression between spherical equivalent manifest refraction/keratometric power was 0.12/0.04 D (0.06/0.05 D) from 9 to 12 months, 0.01/0.04 D (0.06/0.06 D) from 12 to 15 mo, and -0.03/±0 D from 15 to 18 months. Mean uncorrected visual acuity improved from 20/100 to 20/32 (20/63 to 20/32). No eye lost more than 1 line of BSCVA. The amount of correction showed an age dependency.

CONCLUSION: DTK is a minimally invasive, low-risk procedure, and was effective for correction of low hyperopia and low to moderate hyperopic astigmatism in patients less than 40 years. [J Refract Surg 2004;20:155-161]
Recovery of Corneal Sensitivity to Mechanical and Chemical Stimulation After Laser in situ Keratomileusis
Authors: Gallar Juana , Acosta M Carmen , Moilanen Jukka A O , Holopainen Juha M , Belmonte Carlos , Tervo Timo M T
Published: December 2019

ABSTRACT

PURPOSE: To evaluate the time course of changes in corneal sensitivity to mechanical and chemical stimuli produced by laser in situ keratomileusis (LASIK) in humans.

METHODS: We performed a cross-sectional study of 17 LASIK-operated eyes (VisX S2, equipped with version 2.50-3.10 software) and 15 control eyes of 17 individuals to evaluate regeneration of corneal sensitivity after LASIK. Gas pulses of variable flow and compositions were applied to the cornea by a non-contact gas esthesiometer. Mechanical stimuli consisted of air puffs at flows from 0 to 200 ml/min. Chemical stimulation was made with gas pulses containing 0% to 80% CO2 in air at subthreshold flow. Mechanical and chemical thresholds and intensity-response curves for the evoked sensations were determined prior to surgery, and 7 to 9 days, 3 to 5 months, and 1.5 to 2.5 years after surgery.

RESULTS: Corneal sensitivity to mechanical stimulation was enhanced 7 to 9 days after surgery but subsequently dropped markedly and remained significantly below control levels 3 to 5 months after LASIK. Sensitivity to both mechanical and chemical types of stimuli was close to normal 2 years postoperatively.

CONCLUSIONS: Corneal sensitivity decreased immediately after LASIK but mechanical sensitivity showed a transient hyperesthesia 7 to 9 days afterward. Subsequently, a long-lasting and deep hypoesthesia to mechanical and chemical stimuli was observed. Gas esthesiometry revealed that disturbances of corneal sensation still exist at times when coarse mechanical sensitivity appeared to be normal. [J Refract Surg 2004;20:229-235]
Comparison of the Colvard Pupillometer and the Zywave for Measuring Scotopic Pupil Diameter
Authors: Cheng Arthur C K , Lam Dennis S C
Published: December 2019

ABSTRACT

PURPOSE: To evaluate the accuracy and repeatability of two pupillometers.

METHODS: Two pupillometers, the Colvard and Zywave, were used to measure scotopic pupil diameter for 64 consecutive patients. Accuracy and repeatability were assessed by two independent examiners and statistical analysis was performed using the comparison method described by Bland and Altman.

RESULTS: Mean scotopic pupil diameter was 5.96 ± 0.69 mm with the Colvard pupillometer and 5.77 ± 0.85 mm with the Zywave. The difference between the Colvard and Zywave measurements was 0.21 ± 0.56 mm (P<.001). The coefficient of interrater repeatability was smaller for the Colvard (0.59) than for the Zywave (1.17). The mean difference between the pupillometers for each examiner was 0.17 ± 0.47 mm (P<.01) for examiner 1 and 0.26 ± 0.64 mm (P<.01) for examiner 2.

CONCLUSIONS: Scotopic pupil diameter measured with the Zywave was statistically but not clinically significantly smaller than that measured with the Colvard pupillometer. The Zywave produced an inter-rater repeatability comparable to other devices although not as good as the Colvard pupillometer. [J Refract Surg 2004;20:248-252]
Holmium Laser Thermal Keratoplasty for Hyperopia in Eyes Overcorrected With Laser in situ Keratomileusis for Myopia
Authors: Gozum Nilufer , Ayoglu Buket , Gezer Acun , Goker Sinan , Gucukoglu Ahmet
Published: December 2019

ABSTRACT

PURPOSE: To assess the efficacy and safety of holmium laser thermal keratoplasty (Ho:LTK) for hyperopia in eyes overcorrected after laser in situ keratomileusis (LASIK) for myopia.

METHODS: We performed a prospective evaluation of Ho:LTK in eyes with secondary hyperopia from +1.00 to +5.50 D after LASIK. Thirty-seven eyes of 23 patients received one concentric 8-spot application at the 6-mm-diameter zone. Mean patient age was 41.3 ± 13.0 years (range 20 to 68 yr). Mean corneal thickness was 455.86 ± 31.20 µm (range 373 to 506 µm).

RESULTS: Mean spherical equivalent refraction changed from +2.30 ± 1.08 D to +0.45 ± 1.00 D at 12 months after Ho:LTK. Thirty-one eyes (84%) were within ±1.00 D of emmetropia and 25 eyes (68%) were within ±0.50 D at 1 year. Mean change in refraction was 1.84 ± 0.92 D. No eye lost 2 lines of best spectacle-corrected visual acuity.

CONCLUSIONS: Ho:LTK is a suitable alternative for correcting secondary hyperopia resulting from LASIK for myopia. Parameter adjustments may be necessary for improving the results. [J Refract Surg 2004;20:253-257]
Laser in situ Keratomileusis for Residual Hyperopic Astigmatism After Conductive Keratoplasty
Authors: Kymionis George D , Aslanides Ioannis M , Khoury Aghlab N , Markomanolakis Marinos M , Naoumidi Tatiana , Pallikaris Ioannis G
Published: December 2019

ABSTRACT

PURPOSE: To report a case of laser in situ keratomileusis (LASIK) in a patient with previous conductive keratoplasty.

METHODS: A 48-year-old man underwent conductive keratoplasty for low hyperopic astigmatism (manifest refraction OD: +2.25 -0.50 x 77°; OS: +2.50 -0.50 x 105°). Three months postoperatively, UCVA was 20/25 and BSCVA was 20/20 in both eyes; manifest refraction OD: -0.25 -0.75 v 110°; OS: +0.75 -0.75 x 50°. Sixteen months after the operation, regression of refractive outcome was (manifest) OD: +1.75 *1.25 x 90°; OS: +2.50 -0.50 x 85°; UCVA was 20/40 in the right eye and 20/63 in the left eye and BSCVA was 20/20 in both eyes. LASIK was performed for hyperopic regression in the left eye using an automated microkeratome (Alcon SKBM, 130-µm plate; Aesculap-Meditec MEL 70 excimer laser).

RESULTS: LASIK was uneventful and no intraoperative or postoperative complications related to the previous conductive keratoplasty procedure or LASIK were observed. Three months after LASIK and 19 months after the initial conductive keratoplasty, the patient's left eye was emmetropic; UCVA was 20/20^sup -2^, BSCVA was 20/20 and manifest refraction was +0.25 -0.25 x 35°. There was a uniform increase in topographical steepening. Visual acuity, refraction and topographic findings remained unchanged at 6 months.

CONCLUSIONS: Even though our experience is limited, treatment of hyperopia with LASIK in an eye with refractive regression following previous conductive keratoplasty resulted in a predicted refractive outcome, with no complications, and improvement in visual acuity at 6 months followup. [J Refract Surg 2004;20:276-278]
Wavefront Aberrations Following Laser in situ Keratomileusis and Refractive Lens Exchange for Hypermetropia
Authors: Ma Luxin , Atchison David A , Albietz Julie M , Lenton Lee M , McLennan Suzanne G
Published: December 2019

ABSTRACT

PURPOSE: To compare the magnitude of aberrations in eyes after elective hypermetropic laser in situ keratomileusis (LASIK) and refractive lens exchange (clear lens replacement).

METHODS: Forty-nine patients (92 eyes) had hypermetropic LASIK and 28 (48 eyes) had refractive lens exchange; 23 hypermetropic subjects (41 eyes) were the control group. LASIK was performed with the Nidek EC-5000 excimer laser; ablation zones 5.5 to 6.0-mm in diameter with transition zones 7.5 to 8-mm in diameter. For refractive lens exchange, all but four IOLs were made of foldable acrylic. Aberrations and corneal topography were measured with the Nidek OPD-Scan model ARK10000 more than 12 months after surgery. The higher-order root-mean-square (HORMS) wave aberrations for combined third to sixth Zernike aberration orders and the Zernike spherical aberration coefficient C ?? at both 4.2-mm and 6.0-mm pupil sizes were calculated.

RESULTS: For the LASIK group, surgical refractive change correlated significantly with total, corneal, and internal HORMS and spherical aberrations (except with internal spherical aberration for a 4.2-mm diameter pupil). For the refractive lens exchange group, there were no significant correlations of surgical refractive change with any of these factors. Similarly, there were no significant correlations of refraction with any of these factors for the control group. For a 3-diopter change in refraction with 6-mm pupils, LASIK doubled the total HORMS aberrations. LASIK changed the sign of spherical aberration from positive to negative by increasing the negative asphericity of the anterior cornea. Taking age differences between groups into account, refractive lens exchange increased the total HORMS aberrations by 40% compared with that of the control group, but this was not statistically significant. However, refractive lens exchange significantly increased total spherical aberration.

CONCLUSION: Refractive lens exchange was a better refractive procedure than LASIK for minimizing total higher order optical aberrations that accompany hypermetropic refractive surgery. [J Refract Surg 2004;20:307-316]
Rate of Cataract Formation in 343 Highly Myopic Eyes After Implantation of Three Types of Phakic Intraocular Lenses
Authors: Menezo José L , Peris-Martínez Cristina , Cisneros-Lanuza Angel L , Martínez-Costa Rafael
Published: December 2019

ABSTRACT

PURPOSE: To assess the feasibility of using phakic intraocular lenses (PIOL) to treat high myopia, and evaluate the incidence of cataract, comparing three different lens types.

METHODS: From 1989 to 2002, we implanted three different phakic intraocular lenses (PIOL) in 343 eyes of 232 patients; 231 eyes recieved an Ophtec (Worst-Fechner model, iris-claw), 89 an Adatomed (silicone posterior chamber), and 23 a Staar (posterior chamber, models V2, V3, V4). Average follow-up was 96.2 months for the Ophtec group, 31.5 months for the Adatomed group, and 19.3 months for Staar group. Eyes that subsequently developed cataract were studied for clinical evolution and had PIOL explantation and cataract extraction.

RESULTS: Nuclear cataract developed in 7 of 231 eyes (3.04 %) with an Ophtec lens. Anterior subcapsular cataract developed with the two types of posterior PIOLs (Adatomed group: 38/89 eyes, 42.69%; Staar group: 3/23 eyes, 13.04%). Anterior subcapsular cataract in the Adatomed group developed more rapidly compared to the Staar group. We explanted 7 lenses in the Ophtec group, 16 lenses in the Adatomed group, and 2 lenses in the Staar group (models V2 and V3 only). Patient age older than 40 years at implantation of PIOLs and axial length greater than 30 mm were factors significantly related to nuclear cataract formation and the Ophtec lens. However, these two factors had a weaker correlation with the posterior phakic lenses (Adatomed, Staar) for high myopia than with the Ophtec lens. Postoperative best spectacle -corrected visual acuity remained stable after explantation, phacoemulsification, and posterior chamber lens implantation.

CONCLUSIONS: Delayed cataract development and cataract type (nuclear) in patients with an Ophtec lens and the variables of patient age (>40 yr) and axial length (>30 mm) may considered prognostic factors. Other factors such as lens design, material, and placement probably influenced cataract formation in patients with the Adatomed and Staar PIOLs. The lens styles used in this study are no longer manufactured. [J Refract Surg 2004;20:317-324]
Monovision Laser in situ Keratomileusis for Pre-presbyopic and Presbyopic Patients
Authors: Miranda Danielle , Krueger Ronald R
Published: December 2019

ABSTRACT

PURPOSE: To evaluate the outcome and success of refractive surgery in pre-presbyopic and presbyopic patients with monovision after laser in situ keratomileusis (LASIK).

METHODS: We performed a retrospective analysis of 748 eyes of 374 patients over 35 years of age treated in one or both eyes for a monovision outcome using the Alcon LADARVision 4000 laser. Analysis of age at the time of surgery, gender, bilateral versus unilateral treatment, targeted outcome, and patient acceptance are reported.

RESULTS: The success rate of monovision patients in this study was 92.5%. Acceptance rate was higher in older patients, although there was no significantly greater acceptance of monovision for any of the variables studied (P values >.26).

CONCLUSIONS: Monovision is a valuable option for pre-presbyopic and presbyopic patients considering refractive surgery. [J Refract Surg 2004;20: 325-328]
Wavefront-guided Ablation With Bausch and Lomb Zyoptix for Retreatments After Laser in situ Keratomileusis for Myopia
Authors: Castanera Jorge , Serra Alicia , Rios Carlos
Published: December 2019

ABSTRACT

PURPOSE: To evaluate the efficacy of wavefrontguided ablation for treatment of residual refractive error and higher order aberrations after laser in situ keratomileusis (LASIK) for myopia.

METHODS: Twenty-one eyes of 13 patients with residual refractive error after myopic LASIK were treated with a wavefront-guided ablation with the Zyoptix technique. In 13 eyes of 8 patients (Group A) we lifted the flap with an epitheliorhexis technique; in 8 eyes of 5 patients (Group B) we cut a new flap with a Hansatome microkeratome.

RESULTS: Preoperative root mean square (RMS) values were 1.370 for second order aberrations, 0.382 for total higher order aberrations, 0.273 for third order, 0.243 for fourth order, and 0.052 for fifth order aberrations. Three months postoperatively, RMS values decreased significantly to 0.278 (second order), 0.189 (total higher order), 0.138 (third order), 0.107 (fourth order), and 0.038 (fifth order). Ablation depth was two times greater than needed with a standard Planoscan treatment. Patients in the microkeratome re?ut group showed a trend toward overcorrection, and residual astigmatism was higher (-0.75 ? 0.58 D) than in the flap lift group (-0.25 ? 0.29 D).

CONCLUSIONS: Wavefront-guided ablation was an effective method to correct residual refractive error and higher order aberrations after myopic LASIK. Functional and refractive outcomes were better when we lifted the flap than when we re?ut the flap. [J Refract Surg 2004;20:439-443]
Smoothing of the Ablated Porcine Anterior Corneal Surface Using the Technolas Keracor 217C and Nidek EC-5000 Excimer Lasers
Authors: Lombardo Marco , Serrao Sebastiano
Published: December 2019

ABSTRACT

PURPOSE: To demonstrate efficacy of a smoothing technique to increase regularity of the anterior corneal surface after photorefractive keratectomy (PRK), using two different excimer lasers.

METHODS: Spherical ablations of -10.00 D were performed on 11 fresh porcine corneas using either the Technolas Keracor 217C scanning-spot or the Nidek E C -5000 scanning-slit beam excimer laser. Following the procedure, we performed a phototherapeutic keratectomy treatment (smoothing technique) on half of the corneal surface. The smoothing technique was performed using a viscous solution of 0.25% sodium hyaluronate, which was spread on the cornea prior to the procedure. The ablation zone was 6 mm in diameter and the transition zone extended to 3 mm. The ablation depth was set at 10 ???. Corneas were then examined with scanning electron microscopy.

RESULTS: Smoother treatment zones were apparent in porcine corneas in which smoothing was performed following PRK, with both laser systems. Results from the two lasers were not directly compared.

CONCLUSIONS: The smoothing procedure performed following PRK using a viscous 0.25% sodium hyaluronate masking solution and a scanning laser system rendered the porcine corneal surface more regular. [J Refract Surg 2004;20:450-453]
Very High Frequency Ultrasound Biometry of the Anterior and Posterior Chamber Diameter
Authors: Rondeau Mark J , Barcsay György , Silverman Ronald H , Reinstein Dan Z , Krishnamurthy Rupa , Chabi Almira , Du Ted , Coleman D Jackson
Published: December 2019

ABSTRACT

PURPOSE: To measure the largest diameter of the anterior chamber (AC) and posterior chamber (PC) dimension and its orientation and determine the relationship with the principal keratometric meridians.

METHODS: Twenty-eight eyes of 14 subjects were scanned with high frequency (50 MHz) ultrasound in sequential meridional scan planes at 30? increments. Observer identified angle and ciliary sulcus recess boundaries in each patient scan set were fit with an elliptical model to obtain the ellipse semi-major axis corresponding to the largest diameter and its meridional orientation. Anterior and posterior chamber diameters from raw data and model fit were compared using linear statistics. Circular statistics were used to compare the orientation of the largest diameter for raw ultrasound measurements, model estimations of largest diameter, and autorefractor determined keratometric axes.

RESULTS: The mean model diameters were anterior chamber OD 12.07 mm (0.32 SD); anterior chamber OS 12.06 mm (0.36 SD); posterior chamber OD 12.35 mm (0.42 SD); posterior chamber OS 12.33 mm (0.43 SD). The general trend for orientation of the meridian of largest diameter was in the horizontal meridian. In over 35% of eyes the difference between AC or PC meridian and the flat keratometric axis was greater than 20 degrees.

CONCLUSIONS: Accurate and reproducible anterior segment biometry depends on visualization of structures and minimization of eye and head movement error. The range and standard deviation of the diameter and orientation measures suggests anatomic variation is sufficient to require biometry for proper sizing and placement of intraocular devices that use angle or sulcus fixation. [J Refract Surg 2004;20:454-464]
Measuring Visual Acuity-Mesopic or Photopic Conditions, and High or Low Contrast Letters?
Authors: Pesudovs Konrad , Marsack Jason D , Donnelly William J , Thibos Larry N , Applegate Raymond A
Published: December 2019

ABSTRACT

PURPOSE: To develop s ingle -valued wavefront aberration metrics that correlate strongly with visual performance. The purpose of this study is to explore whether photopic high contrast visual acuity (VA) is an appropriate visual performance reference and whether mesopic and/or low contrast testing provides any advantage.

METHODS: Subjects from the Texas Investigation of Cataract Optics study (N = 148) ranged in age from 21.6 to 83.8 years and from clear lens to dense nuclear cataract. Visual acuity was measured under four conditions: photopic high (VA^sub PHC^) and low (VA^sub PLC^) contrast, mesopic high (VA^sub MHC^) and low (VA^sub MLC^) contrast (photopic = 280 cd/mp 2, mesopic = 0.75 cd/mp 2). Variables were tested for compliance with normality (-2.00 < skew and kurtosis < 2.00) and transformed if required. Linear regression and Bland-Altman 95% limits of agreement (±1.96 SD) were used to examine relationships between VA variables and between VA and wavefront aberration metrics.

RESULTS. The two photopic measures VA^sub PHC^ (skew = 2.57, kurtosis = 12.2) and VA^sub PLC^ (1.67, 5.41) were poorly distributed, but the two mesopic measures VA^sub MHC^ (0.88, 1.67) and VA^sub MLC^ (0.29, -0.18) were normally distributed. Strong correlations existed between the (transformed) VA variables (R: 0.53 to 0.84). However, limits of agreement ranged over 0.30 to 0.42 logMAR, whereas retest data suggested a range of 0.15. All four were offered in stepwise multiple linear regression for 30 wavefront metrics: 20 included VA^sub MLC^ alone, two included VA^sub PLC^, two included VA^sub MHC^ and six included both VA^sub MLC^ and VA^sub MHC^; Rp 2 averaged 25%.

CONCLUSION: Although strongly correlated, low contrast and/or mesopic VA testing provides different information. Wave aberration metrics correlate better with VAMLC making this the visual performance test of choice. [J Refract Surg 2004;20:S508-S514]
Ablation Design in Relation to Spatial Frequency, Depth-of-focus, and Age
Authors: Charman W Neil
Published: December 2019

ABSTRACT

PURPOSE: To consider factors relevant to the design of wavefront-aberration-based customized ablations.

METHODS: Review.

RESULTS: Ablations that seek to eliminate all wavefront aberrations, both second- and higherorder, may not be optimal for all patients. This is particularly the case for presbyopes. Their main requirement will normally be for extended binocular depth-of-focus to yield adequate distance and near vision with good retinal contrast at lower spatial frequencies, rather than the highest levels of acuity and modulation transfer function at a single distance. For many presbyopes, this can be achieved by aiming for monovision correction or low myopic astigmatism, with reasonable but not necessarily complete correction of higher-order aberrations. This compromise allows a range of everyday tasks to be carried out, including face recognition and reading.

CONCLUSION: The targeted correction of wavefront aberration should take into account the visual needs and preferences of the individual patient. [J Refract Surg 2004;20:S542-S549]
Wavefront-guided Laser Epithelial Keratomileusis With the WaveLight Concept System 500
Authors: von Mohrenfels Christoph Winkler , Huber Andrea , Gabler Bernhard , Herrmann Wolfgang , Kempe Alexander , Donitzky Christof , Lohmann Chris P
Published: December 2019

ABSTRACT

PURPOSE: Laser epithelial keratomileusis (LASEK) is a technique of refractive surgery for treatment of myopia. More than 90% of patients are within the intended correction of ?0.50 diopters (D), without any unwanted side effects. After conventional refractive surgery, higher-order aberrations are induced. To reduce these aberrations, we used wavefront-guided ablation.

METHODS: Twenty patients with visual problems in ambient light were included. The primary surgery was 141 to 463 days before the re treatment. LASEK was performed with the Camellin technique with 20% EtOH for 30 seconds. Before surgery, the root mean square (RMS) values were measured and the laser treatment was performed with the WaveLight Concept System 500 (WaveLight Laser Technologie AG). The preoperative spherical equivalent refraction was -1.22 D (SD 0.57 D) and the astigmatism was -0.42 D (SD 0.25 D). Preoperatively and 6 months postoperatively, a comprehensive examination was performed.

RESULTS: All retreatments were performed without any intra- or postoperative complications. All patients reported an improvement of vision. The 6-month postoperative refraction was 0.25 D (SD 0.36 D). RMS decreased significantly from 0.72 to 0.47. RMS fourth order also decreased significantly from 0.60 to 0.30 and the spherical aberration decreased significantly from 0.57 to 0.28.

CONCLUSIONS: In earlier studies, patients reported reduction of contrast vision, even after resurge ry. Our patients showed a significant reduction of higher-order aberrations and better contrast vision after retreatment with wavefront guided LASEK. Retreatment with wavefront-guided LASEK has the potential to correct night vision problems after excimer laser surgery. [J Refract Surg 2004;20:S565-S569]
Corneal Asphericity and Retinal Image Quality: A Case Study and Simulations
Authors: Somani Seema , Tuan K Ashley , Chernyak Dimitri
Published: December 2019

ABSTRACT

PURPOSE: The optical quality of retinal images is dependent on the refracting elements of the eye including the nominally aspheric cornea and crystalline lens. This paper presents a retrospective theoretical analysis of the impact of corneal asphericity on the quality of retinal images. Clinical data are from the VISX Incorporated CustomVue IDE.

METHOD: Topography, contrast sensitivity, and visual acuity data were collected from 278 myopic eyes before and after wavefront-guided laser surgery. The measured corneal surface of each eye was fitted to a conic, and a Q-value was computed for a 5.5-mm pupil. A model eye was used to simulate various amounts of optical asphericity.

RESULTS: Preoperatively, most corneas exhibited negative conic shape constants. Postoperatively, corneas were about equally divided between positive and negative conies. There was no statistically significant correlation between the shape of the cornea and the subjects' perceptions of image quality including contrast sensitivity and visual acuity. Simulations showed that the corneal Q-value can vary from more to less prolate depending upon the shape of the internal surface.

CONCLUSION: Following wavefront-guided laser in situ keratomileusis (LASIK), contrast sensitivity is usually good and is not dependent upon the corneal conic shape. Better visual outcomes are more likely with a customized shape than a standard best conic shape. [J Refract Surg 2004;20:S581-S585]
Randomized Comparison of Custom Laser in situ Keratomileusis With the Alcon CustomCornea and the Bausch & Lomb Zyoptix Systems: One-month Results
Authors: Durrie Daniel S , Stahl Jason
Published: December 2019

ABSTRACT

PURPOSE: To compare the early visual results of custom laser in situ keratomileusis (LASIK) outcomes for two different excimer laser systems.

METHODS: This is a preliminary report of an ongoing prospective study that evaluated 30 patients (60 eyes) who were randomized to one of two custom LASIK treatment groups: 15 patients (30 eyes) with the Alcon CustomCornea laser system (Alcon Laboratories Ine, Fort Worth, Tex) and 15 patients (30 eyes) with the Bausch & Lomb Zyoptix laser system (Bausch & Lomb, Rochester, NY). These matched patients were required to qualify for treatment with both custom laser systems. All flaps were created with the IntraLase femtosecond laser (IntraLase Corp, Irvine, Calif) using a superior hinge. Early outcome measures are uncorrected visual acuity (UCVA) at 1 day, 1 week, and 1 month postoperative; manifest refractions at 1month follow-up; and a comparison of 1 -month postoperative UCVA to preoperative best spectaclecorrected visual acuity (BSCVA). Wavefront, topography, contrast sensitivity, and subjective questionnaires were also performed and will be reported after 3-month follow-up.

RESULTS: At 1 month, the percentage of eyes with UCVA of 20/20 and 20/40 were similar with 93% and 100%, respectively, for CustomCornea eyes and 90% and 97%, respectively, for Zyoptix eyes. A difference between the two groups is in the percentage of eyes with UCVA of 20/16, 20/12.5, and 20/10 with 80%, 47%, and 13%, respectively, for CustomCornea and 70%, 10%, and 0%, respectively, for Zyoptix. The mean residual spherical equivalent refraction was +0.01 ? 0.34 diopters (D) for CustomCornea and -0.04 ? 0.38 D for Zyoptix. The two groups are similar at ?1.00 D of intended correction, with CustomCornea 100% and Zyoptix 97%. However, ?0.25 D the CustomCornea group was 10% more accurate at 73% versus 63% for the Zyoptix group. The efficiency ratio (postoperative UCVA compared to preoperative BSCVA) was greater for the CustomCornea group at 20/20, 20/16, 20/12.5, and 20/10 levels.

CONCLUSION: Custom LASIK with CustomCornea and Zyoptix is safe and effective and produces excellent early visual outcomes. This study demonstrates that current standard metrics for reporting refractive surgery visual outcomes are not adequate for evaluating wavefront-guided laser vision correction procedures. Amending the standard reporting metrics to include visual outcomes at the 20/16, 20/12.5, and 20/10 levels; accuracy at the ?0.25 D of attempted; and postoperative UCVA compared to preoperative BSCVA will improve our ability to analyze wavefront-guided outcomes. [J Refract Surg 2004;20:S644-S648]
E-Books Preference Compared to Print Books Based on Student Perceptions: A Case of University of Fort Hare Students
Authors: Makwanya Comfort , Oni Olabanji
Published: December 2019

Technology advent has been transforming students’ perceptions and preferences mostly on how they acquire information and learn. The way students perceive e-books and print books significantly influences the format they prefer to use for academic purposes. Recently, the accessibility of e-books on assorted mobile gadgets is substituting the conventional print based resources which are regarded costly in production, sharing and also heavy. Differing views on the format (e-book or print) that students prefer for academic purposes to improve their educational experience exist of which most studies have been done in developed countries. Therefore, a research that reveals students’ perceptions and preferences towards the two book formats in the nation of South Africa can afford a better understanding and conclusion on an African student. This study aimed to determine students’ preference on using e-books and print books in meeting academic information needs based on perceptions. The study adopted a cross-sectional research design and a questionnaire as a research instrument which was administered to students at the University of Fort Hare. Findings revealed that students preferred using both (e-books and print books) for their academic needs. Moreover, they perceived e-books to be as good as print books, easy and friendly to use and capable of providing sufficient information to meet educational needs.

 
Designing a Theoretical Integration Framework for Mobile Learning
Authors: Zidoun Youness , Dehbi Rachid , Talea Mohamed , El Arroum Fatima-Zohra
Published: December 2019

New technologies are rapidly changing mobile learning and making it difficult to control. In addition to educational factors and learning content, a modern mobile learning system must take into account the technical and personal aspects of learning, the devices and aspects related to its evolution and interoperability. Teaching on the other hand has also evolved involving more flexibility in tasks and learning stages, thus using modern technologies that offer more alternatives now. In addition, such tasks may be specific to the learning content as well as the learning context or furthermore the learner's environment.

Traditionally, mobile platform design relies on the skills of a mobile developer whose knowledge allows him to design mobile applications that are useful to users. But with mobile learning, the design phase involves more than just mobile development skills. For example, if you are designing a platform for practical work, the instructors responsible for the training should be involved. However, the empirical results show that educators do not integrate technology effectively into their curricula. To enable these instructors to develop mobile learning platforms, it is important to facilitate their integration through a theoretical model that will take into account all the ingredients necessary to complete this learning and to balance them in order to ensure its efficiency. In this study authors used a thematic synthesis methodology to present a framework for mobile devices integration in learning. They focused on three models that they think are the most cited in the field of ICT (information and communication technologies) integration in learning.

The five-axis framework consists of enriching the TPACK framework(Technological Pedagogical Content Knowledge model in order to more precisely address mobile learning by covering the following parts: pedagogy, content, mobile technology, learning environment and learner’s profile. It describes relatively in depth the various factors involved as well as the effective interconnection to be ensured to achieve an optimal and efficient integration of m-learning. Balancing those five parts will be a matter of plural reflection when designing or consulting on a mobile learning platform.
Development of Countenance Application Oriented on Combining ANEKA-Tri Hita Karana as A Mobile Web to Evaluate the Computer Knowledge and Morality
Authors: Divayana Dewa Gede Hendra , Ariawan I Putu Wisna , Adiarta Agus
Published: December 2019

The principal objective of this study was to introduce the existence on development of Countenance evaluation application that can be used to evaluate the moral and quality of students’ computer knowledge by using evaluation indicators which oriented to combining between ANEKA values with the Tri Hita Karana concept. This research was developed by using the Borg & Gall method, which focuses on the stages of creating a mobile web-based evaluation application, field trial stage, and revision stage of field trial results. The subjects involved in creating the application as much as three peoples, subjects involved in the field trial as much as 94 peoples, and subjects involved in the revision of field trial as much as three peoples. The instruments that were used in conducting the assessment on the field trial was in questionnaires form. The technique that was used to analyze the collected data from field trials results using quantitative descriptive techniques by determining the average of percentage from application quality that was compared to a standard score of application quality that refers to eleven’s scale. The study results showed that the quality of the evaluation application belongs to a very good category, so it was ready to be implemented, and it is no need to be done the major revision.
New Efficient Caching Strategy based on Clustering in Named Data Networking
Authors: Fethellah Nour El Houda , Bouziane Hafida , Chouarfia Abdallah
Published: December 2019

The Named Data Networking NDN is one of the most proposed architecture for the new model of Internet communications based on contents distribution, called Information-Centric Network ICN. It is widely accepted by the research community since it has become dominant in ICN design that resolves TCP-IP based Internet problems such as bandwidth, delay, location dependent and congestion. Based on location host IP addresses, TCP-IP designed for Peer-to-Peer communication P2P. NDN architecture is oriented Content Centric Networking CCN, where the data is stored on routers and distributed to users from the nearest router.  Cache capacities of routers are limited compared to forwarded contents. To move from TCP-IP model to CCN model, many papers propose several new contents distribution based architecture ICN. In this paper, we propose a novel strategy to optimize the use of network resources inspired from Network clustering and cluster head selection in MANETs. Specifically, the improved K-medoids cluster algorithm is used to divide the global network in clusters, where for each cluster; three routers are selected as content routers. The first is the main caching router as well as the second and the third are the secondary caching router. The caching router selection process relies on three relevant criteria consisting of the distance between a node and its cluster centroid, the number of neighbors, and the congestion level. Two Multi Attribute Decision–Making methods MADM are applied, namely TOPSIS and AHP. Performance analysis of our proposed strategy with the established criteria showed  � its effectiveness and strong potential.
Augmented Reality Storytelling – Narrative Design and Reconstruction of a Historical Event in situ
Authors: Liestoel Gunnar
Published: December 2019

How may we best utilize mobile augmented reality for storytelling when reconstructing historical events onlocation? In this article we present a series of narrative design considerations when developing an augmented reality application recreating the assault on Omaha Beach in the early morning on D-Day. To what extent may we select existing genre conventions from, for example, documentary film, and adapt them to a location–based audio–visual medium like AR? How can we best combine sequence and access, the narrative flow of an unfolding historical event with the availability of background information, in order to enrich the experience of the story, but without distorting its coherence? To what extent may we draw from existing and well known media representations of the Omaha Beach landing? How was the battle documented with contemporary means? We present the rich documentation of photos, films, drawings, paintings, maps, action reports, official reports, etc., and discuss how these have been employed to create the published AR situated simulation. We also describe and discuss the testing and evaluation of the application on location with visitors, as well as online tracking of its current use.
Development of Augmented Reality (AR) Based Gamelan Simulation with Leap Motion Control
Authors: Permana Frihandhika , Tolle Herman , Utaminingrum Fitri , Dermawi Rizdania
Published: December 2019

One of the traditional musical instrument from Indonesia is gamelan, that is now less desirable because people nowadays prefer to play modern musical instruments, or because of its expensive price. This study combines the modern technology of AR and Leap Motion and also utilizes the sophisticated smartphone to develop a gamelan simulation that is presentable to the user. There are two kinds of an experiment performed in this research. The first is Augmented Reality (AR) experiment which authenticates that the distance and the height parameters are the keys to get a 100% success in running the gamelan simulation. The distance is ranged from 45 cm to 65 cm and the height is ranged from 25 cm to 30 cm. And the second one is the usability evaluation to five users, who resolves the completion task very well, acquires the result of 86.48%.
Heterogeneity in IoT-based Smart Cities Designs
Authors: Haj Qasem Mais , AlMobaideen Wesam
Published: December 2019

Smart city is a strategy of supporting new way of living using data that are collected from different types of electronic devices, analyzed and utilized to enable efficient resource usability and service optimization. Applications of various nature are elaborated in the smart cities, such as traffic planning applications, crowd monitoring, public health care, security, economy and urban planning. Thus, various requirements are needed to incorporate and facilitate efficient development of these applications in the smart city design. Accordingly, smart city can be distinguished via the requirements that support these applications. In this study, the requirements of smart city in relations to the involved applications and its influence on the smart city design are discussed.  A list of smart city requirements is concluded and the potentials of various network architecture to facilitate such requirements are discussed. Based on the requirements and the architectures, the existing smart city designs are evaluated and compared. 
Wilfried Steiner’s Der Weg nach Xanadu – an Austrian Campus Novel?
Authors: Fuchs Dieter
Published: December 2019

This article focuses on Wilfried Steiner’s 2003 novel Der Weg nach Xanadu / The Way To Xanadu which appears to be an Austrian campus novel owing to the setting of the Austrian world of academia in its first part. Owing to its lack of local coloring, however, the Vienna-based plot of the first part does not feature a (stereo)typically ‘Austrian’ genius loci. Although this part of the text echoes features of the international campus novel tradition, it may be definitely not considered an Austrian campus novel. The second part of the novel is set in the Lake District, focuses on Coleridge’s Romantic poetry and the Doppelgänger-motif. Whereas the first part may be vaguely contextualized within the international campus novel tradition, the second part is deeply imbued with the Romantic tradition of the Künstlerroman or artist’s novel.
Ideological Influences on the Reception of Mark Twain among Slovenians across the Atlantic
Authors: Trupej Janko
Published: December 2019

The article discusses the reception of Mark Twain and his works in serial publications by Slovenian immigrants in the United States of America. The analysis encompassed writings published in newspapers and magazines with different ideological orientations, from the beginning of the 20th century to mid-century. The article compares Twain’s reception in left-wing and right-wing publications and furthermore discusses the extent to which the reception was affected by the contemporary political situation in the United States.
Les apories du surréalisme
Authors: Turk Boštjan Marko
Published: December 2019

La présente étude se propose de répondre à la question des apories qui concernent la conception surréaliste du langage et de ses outils poétiques. Les surréalistes démettaient du premier rang la disposition d’esprit d’après laquelle ce qui existe possède sa raison d’être et peut – par conséquent – être considéré comme intelligible. Ils postulaient qu’il y avait une sphère au-delà de la réalité dans laquelle la raison n’était pas capable de pénétrer. Or, tous les outils que les surréalistes proposaient afin d’atteindre la surréalité étaient conçus sur les modalités du raisonnement. Ainsi, ils se sont laissés piéger par leur propre piège.
Traduire Chateaubriand dans le Vermont : les Mémoires d’Outre-Tombe dans Le livre des illusions de Paul Auster
Authors: Marinčič Katarina
Published: December 2019

Cet article présente une analyse des rapports intertextuels entre le roman Le livre des illusions (The Book of Illusions) de Paul Auster et les Mémoires d’Outre-Tombe de François-René de Chateaubriand. Le protagoniste-narrateur du roman, bouleversé par une tragédie personnelle, recouvre une raison de vivre dans la tâche quasi impossible de faire une traduction intégrale des Mémoires d’Outre-Tombe. Au cours de l’histoire racontée dans le roman, l’immensité de ce travail entre au second plan. Initialement ressentie comme « un tas de charbon à pelleter », l’autobiographie de Chateaubriand devient un modèle à suivre au niveau formel aussi bien qu’au niveau moral. L’ambition de parler de l’au-delà s’impose à la fois comme l’objectif de vie du protagoniste et comme le squelette narratif du roman.
Refugee Experience in Alan Gratz’s Refugee and Gillian Cross’ After Tomorrow Margarete Rubik Summary As a response to recent
Authors: Rubik Margarete
Published: December 2019

As a response to recent mass migratory movements, numerous children’s novels about refugees have been published in the last decades. The paper analyses two of these novels, Alan Gratz’s Refugee (2017) and Gillian Cross’s After Tomorrow (2013), and puts them into the context of the ‘transcultural turn’ in cultural studies. The paper also presents the results of a survey among university lecturers of various countries about the benefits, challenges and teaching aims of including migrant and refugee literature into the courses they teach.
Transing the Algerian Nation-State: Textual Transgender and Intersex from Pre-Independence to the Black Decade
Authors: Zabus Chantal
Published: December 2019

The article examines the role of transgender and intersex in two key-texts, Marie-Pierre Pruvot’s Marie parce que c’est joli (2007) and Fériel Assima’s Rouhlem ou le sexe des anges (1996). Both texts chronicle two «moments» in Algerian history: 1) the two decades leading to Algerian independence in 1962; and 2) the Black decade spanning 1988-1998. These «moments» are experienced by two protagonists—pied-noir Jean-Pierre Pruvot and MTF Marie-Pierre Pruvot, rolled into one; and Assima’s intersex character raised as a boy, Rhoulem. Both their repressed feminine genders and bodies-in-transition, reflected through the discursive erosion of male genitalia, augur the “transing” of the Algerian nation-state, away from a traditional engendering of the nation-state as male.