bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Corticosteroids in Postoperative Care Following Photorefractive Keratectomies
Authors: Tengroth B , Fagerholm P , Söderberg P , Hamberg-Nyström H , Epstein D 
Published: April 2021

ABSTRACT
Since the start of photorefractive keratectomy (PRK) Seiler has recommended the use of topical corticosteroids during the first 3 months after surgery.1 The rationale for this treatment was to diminish the inflammatory reaction as well as to control the keratocytes from producing collagen and creating scars. Our knowledge of corneal wound healing in general, and after PRK in particular, is very limited and the action of corticosteroids is still unclear. Corticosteroids, when given in comparatively large topical doses, create problems. Between 15 and 30% of patients are corticosteroid responders with increased intraocular pressure. This is a threat to the eye, and also a burden for the doctor as intraocular pressure has to be checked during the treatment. The risk for cataract formation after longer periods of topically administered corticosteroids also has been discussed.
In order to decrease the rise in intraocular pressure, FML has been used in place of dexamethasone. During the 4 years follow up after PRK it has been reported that a number of patients do not regress or get a scar formation if they have not used corticosteroids in the postoperative period. The reasons to avoid topical corticosteroids in some patients are a misunderstanding of their instructions, or those who have had a history of herpes infection or glaucoma.
A double-masked study of the effects of corticosteroids after PRK was performed by Gartry, et al in a small group of patients. After 6 months, the results revealed that there were no differences between the corticosteroid and the non-corticosteroid group. However, the standard deviation was high.
As a result of these findings, our group stopped the use of dexamethasone in the postoperative care of PRK patients. The result of this was very dramatic. Within a month's time, a myopic regression started in a majority of the patients. This regression was greater than that seen in earlier experience. At 3 months, the regression increased and it was impossible to avoid corticosteroids in these patients. As a consquence of these results we did two retrospective studies. (Refract Corneal Surg (suppl) 1993;9:S61-S64.)
Double-Blind Corticosteroid Trial in Identical Twins Following Photorefractive Keratectomy
Authors: Machat Jeffery J 
Published: April 2021

ABSTRACT
The use of topical corticosteroids following excimer laser photorefractive keratectomy (PRK) is widespread, but the role of corticosteroids remains poorly defined. The purpose of this study was to evaluate the use of different corticosteroid postoperative regimens following 193-nanometer excimer PRK in identical twins.
Preoperatively, cycloplegic refraction of the left eye of each twin measured -3.00 D sphere. The full correction was treated utilizing the identical technique within the same 30 minute period. The study was conducted in a double-blind fashion and the refraction, corneal clarity, uncorrected and best spectacle corrected visual acuity, and kerafometry were assessed over the 6-month study period. Both twins were placed on an identical regimen, tapering their drops over a 3-month period.
Corneal clarity was remarkably well preserved with essentially clear corneas observed in both twins. Similarly, both twins achieved 20/15 vision with a cycloplegic refraction of +0.75 D at 6 months. The only difference in the healing pattern was the slightly more rapid visual recovery in twin A. The code was revealled upon the cessation of corticosteroid regimen. Twin A had received fluoromethalone 0.1% and Twin B received dexamethasone 0.1%. Keratometry demonstrated identical flattening. There were no corticosteroid induced intraocular pressure rise or other complications noted.
Identical twins presented a unique opportunity to better understand wound healing following laser keratectomy. The results of this limited study indicated that for at least lower degrees of myopia the need for full strength topical corticosteroids remains questionable. (Refract Corneal Surg (suppl) 1993;9:S105-S107)
The Erodible Mask in Photorefractive Keratectomy for Myopia and Astigmatism
Authors: Brancato Rosario , Carones Francesco , Trabucchi Giuseppe , Scialdone Antonio , Tavola Alessandra 
Published: April 2021

ABSTRACT
This paper reports a new approach for performing photorefractive keratectomy (PRK) that uses an erodible mask to control shape transfer processes. The advantages of this technique, when compared to conventional PRK performed with mechanical diaphragm, are 1) the possibility of transferring almost any shape onto corneal surface; 2) a smoother corneal surface following photoablation; 3) easier eye fixation; and 4) a controlled humidified environment over ablation zone.
We report our experimental study on scanning electron microscopy of polymethylmethacrylate (PMMA) plates ablated using conventional technique versus erodible mask technique; the results showed a smoother surface in the PMMA plate ablated using the erodible mask. We also report our preliminary clinical results of four eyes treated for the correction of myopia combined with astigmatism. Myopia ranged from -2.00 to - 10.00 D, and astigmatism ranged from - 1.50 to -2.50 D. Three months after surgery, all four eyes were within ± 1 .00 D of myopic attempted correction, but astigmatism was completely corrected only in one eye. No complications or scarring have been reported.
We believe the erodible mask could be effective in the correction of myopia and myopic astigmatism, but further improvements are necessary to allow easier alignment of the mask over the eye.
All commonly available excimer laser devices produce photorefractive keratectomy as a concentric ablation of the corneal stroma, deeper in the center than in the peripheral part;1-3 this is produced by means of an iris or diaphragm which, depending on the type of laser, progressively opens or closes, allowing a greater laser beam delivery in the center.4,5 In all cases, the movement of the diaphragm is not progressive and linear but occurs in steps. This results in ablation in micrometrie "steps" that are not perfectly smooth.6 In addition, the concentric aperture (or closure) of the diaphragm produces only circular ablations, able to correct myopia, but not astigmatism or hyperopia. (Refract Corneal Surg (suppl) 1993;9:S125-S130)
Keratomileusis for Myopia With the Excimer Laser (Buratto Technique): Short-Term Results
Authors: Buratto L , Ferrari M , Genisi C 
Published: April 2021

ABSTRACT
We present a prospective clinical study based on the results of 150 consecutive cases of myopic intrastromal keratomileusis cases using the ExciMed UV200 193 nm excimer laser 193-nanometer (Summit Technology, Inc, Waltham, Mass) to reduce high myopia. The mean and standard deviation of the follow up considered was 3.13 ± 1.12. The mean preoperative spheroequivalent was -18.96 ±3.70 D and -2.32 ±2.36 D postoperatively. One hundred twenty-eight eyes (85.3%) were within ± 1.00 D from the intended correction. In a majority of cases the best spectacle corrected visual acuity was unchanged or improved.
No cases of intraoperative complications were observed; postoperative complications are reported. The Buratto technique to correct or reduce high myopia is efficient and safe, while the predictability is satisfactory. (Refract Corneal Surg (suppl) 1993;9:S130-S133.)
Corneal Iron Line Associated with Steep Central Islands after Photorefractive Keratectomy
Authors: Krueger Ronald R , Tersi Ira , Seiler Theo 
Published: April 2021

ABSTRACT
PURPOSE: To report a new corneal iron deposit after excimer laser photorefractive keratectomy (PRK).
METHODS: Two patients with symptomatic persistent steep central islands were noted to have a corneal iron ring at 6 months to 1 year after surgery. This is different from the centred iron spot noted in most patients at 1 year.
RESULTS: One patient had repeated PRK with improvement of his symptoms and resolution of the iron ring.
CONCLUSIONS: A corneal iron ring after excimer laser PRK suggests the presence of a persistent steep central island of stromal origin. Since corneal iron deposition signifies chronicity, symptomatic patients should be retreated as resolution of the steep central island is not likely to occur. [J Refract Surg 1997;13:401-403]
Laser in situ Keratomileusis for Myopia of -2 to -25 Diopters
Authors: Tsai Ray Jui-Fank 
Published: April 2021

ABSTRACT
PURPOSE: To evaluate excimer laser in situ keratomileusis in the treatment of low, high, and excessively myopic eyes in Taiwan, 77 patients (104 eyes) were treated with Nidek EC-5000 excimer laser and divided into four groups.
METHODS: In situ keratomileusis was performed with a Chiron or SCMD microkeratome. The Nidek EC-5000 excimer laser was used, with multiple passes and a multiple zone ablation technique was performed for myopia higher than -10.00 D.
RESULTS: In eyes with a preoperative spherical power equal to or less than -7.00 D (29 eyes of 18 patients), the preoperative cycloplegic mean spherical equivalent refraction was -5.44 ± 1.36 D. The mean postoperative subjective spherical equivalent refraction was 0.25 ± 0.64 D at 1 month, 0.056 ± 0.55 D at 3 months, -0.069 ± 0.415 D at 6 months, and 0.022 ± 0.496 D at 9 months. The predictability of postoperative 9 month results demonstrated that 86.21% of eyes were within ±0.50 D, 96.55% were within ±1.00 D, and 100% were within ±2.00 D of emmetropia.
In eyes with a preoperative spherical power equal to or less than -10.00 D and higher than -7.00 D, 26 eyes of 17 patients had a preoperative cycloplegic mean spherical equivalent refraction of -8.41 ± 0.84 D. The mean postoperative subjective spherical equivalent refraction was -0.043 ± 1.15 D at 1 month, -0.12 ± 0.92 D at 3 months, -0.21 ± 1.05 D at 6 months, and -0.37 ± 1.04 D at 9 months. The predictability of postoperative 9 month results demonstrated that 76.92% of eyes were within ±0.50 D, 80.77% were within ±1.00 D, and 96.5% were within ±2.00 D of emmetropia.
In eyes with a preoperative spherical power equal to or less than -15,00 D and more than than -10.00 D, 40 eyes of 27 patients had a preoperative cycloplegic mean spherical equivalent refraction of -12.65 ± 1.51 D. The mean postoperative subjective spherical equivalent refraction was 0.275 ± 1.72 D at 1 month, -0.30 ± 1.34 D at 3 months, -0.47 ± 1.23 D at 6 months, and -0.62 ± 1.23 D at 9 months. The predictability of postoperative 9 month results demonstrated that 62.5% of eyes were within ±0.50 D, 75% were within ±1.00 D, and 87.5% were within ±2.00 D of emmetropia.
For 19 eyes of 15 patients with a preoperative spherical power greater than -15.00 D, the preoperative cycloplegic mean spherical equivalent refraction was -19.53 ± 2.61 D. The mean postoperative subjective spherical equivalent refraction was -0.40 ± 1.22 D at 1 month, -0.69 ± 1.34 D at 3 months, -0.83 ± 1.40 D at 6 months, and -0.65 ± 2.99 D at 9 months. The predictability of postoperative 9 month results demonstrated that 31.5% of eyes were within ±0.50 D, 52.63% were within ±1.00 D, and 63.16% were within ±2.00 D.
CONCLUSION: LASDX is a safe and effective technique for the treatment of low, high, and excessive myopia. [J Refract Surg 1997;13(suppl):S427-S429]
Patient Satisfaction after Photorefractive Keratectomy for Low Myopia Using the Visual Analogue Scale
Authors: Rushood Abel A , Nassim Hala M , Azeemuddin T 
Published: April 2021

ABSTRACT
OBJECTIVE: To subjectively assess patient satisfaction after photorefractive keratectomy (PRK) for low myopia using the visual analogue scale.
METHODS: We evaluated the satisfaction of 28 patients (53 eyes) who underwent PRK. Their baseline myopia ranged from -0.50 to -5.00 diopters (D) with a refractive cylinder ranging between piano to -2.00 D. They were all treated using the Nidek EC5000 scanning excimer laser with an ablation zone diameter of 5.5 mm and a transition zone diameter of 7.0 nun. Mean follow-up time was 11 months.
RESULTS: Mean satisfaction in this group of patients was 90.95 + 8.9%. We found that age, baseline astigmatism, postoperative refraction, and postoperative haze influenced the satisfaction outcome.
CONCLUSION: Satisfaction assessment after PRK in patients with low myopia using the visual analogue scale is simple, subjective, reproducible, quick, and probably reliable. [J Refract Surg 1997;13(suppl):S438-S440]
Excimer Laser Photorefractive Keratectomy for Hyperopia
Authors: Pietilä Juhani , Mäkinen Petri , Pajari Seppo , Uusitalo Hannu 
Published: April 2021

ABSTRACT
OBJECTIVE: Excimer laser photorefractive keratectomy (PRK) has been shown to be an effective method in the treatment of refractive errors, especially myopia. We evaluated prospectively the efficacy, predictability, stability, and safety of excimer laser PRK in the treatment of hyperopia.
METHODS: Thirty-four hyperopic eyes were treated with an Aesculap-Meditec (MEL 60) excimer laser. The patients were divided into two groups. In the low-moderate hyperopia group, baseline spherical equivalent refraction was between +1.50 and +6.00 diopters (D) (mean, +4.20 ± 1.30 D) and in the high hyperopia group between +6.25 and +9.75 D (mean, +7.70 ± 1.30 D). Follow-up visits occurred 1, 3, 6, and 12 months after surgery.
RESULTS: One-year results were available for a total 27 eyes (79%): 15 eyes with low to moderate hyperopia and 12 eyes with high hyperopia. One year after PRK in the low-moderate group, six eyes (40%) had a refractive error within ±1.00 D of emmetropia, but in the high hyperopia group only two eyes (17%) were within ±1.00 D of emmetropia; three eyes (20%) and one eye (8%) were within ±0.50 D, respectively. The stability of the refractive change was better in the low to moderate hyperopia group; in the high hyperopia group there was still some regression after 6 months. At 12 months, 10 eyes (67%) in the low-moderate and one eye (8%) in the high hyperopia group had postoperative uncorrected visual acuity of 20/40 or better. One eye in the low-moderate hyperopia group saw 20/20 without correction. Only one eye lost two lines of spectacle-corrected visual acuity. Haze was more intense in the high hyperopia group, but it did not reduce visual acuity. No vision-threatening complications were observed.
CONCLUSIONS: When low to moderate hyperopia up to +6.00 D is treated, excimer laser PRK with the Aesculap Méditée MEL60 laser is safe and moderately effective, and refraction stabilizes after 3 months in most eyes . However, PRK is not sufficient to treat high hyperopia in an effective and predictable way. [J Refract Surg 1997;13:504-510]
Flap Measurements With the Hansatome Microkeratome
Authors: Spadea Leopoldo , Cerrone Loredana , Necozione Stefano , Balestrazzi Emilio 
Published: April 2021

ABSTRACT
PURPOSE: To evaluate flap thickness, flap diameter, and hinge length during laser in situ keratomileusis (LASIK) and to correlate these measurements with preoperative keratometric power, central corneal thickness, and patient refraction, gender, and age.
METHODS: In this prospective study of 50 eyes of 28 patients (mean age 31 ? 6.6 yr; range, 24 to 43 yr) results of LASEK for myopia were analyzed (mean spherical equivalent refraction of -7.16 ? 1.69 D; range, -2.75 to -13.50 D). Corneal flaps were created using the Hansatome microkeratome (Baush & Lomb Surgical) with a 160-jtm plate and a 9.5-mm suction ring. Corneal thickness was evaluated using an ultrasonic 50-MHz pachymeter (Sonogage Corneo Gage Plus) and the mean keratometric power was measured with a Corneal Analysis System videokeratographic unit (EyeSys). Data were analyzed using /-test, Pearson product moment correlation coefficient, and Spearman's rho non-parametric correlation coefficients.
RESULTS: Mean corneal flap thickness was 142.6 ± 20.8 µm (range, 107 to 177 /tm), mean flap diameter was 9.9 ± 0.3 mm (range, 9.2 to 10.5 mm), and mean hinge length was 6.2 ± 0.4 mm (range, 5.2 to 7 mm). Statistically significant correlations (P<05) were found between mean keratometric power and flap hinge length, mean keratometric power and flap diameter, preoperative spherical equivalent refraction and flap diameter, corneal thickness and flap hinge length, as well as patient age and corneal thickness.
CONCLUSIONS: The Hansatome microkeratome was an effective and safe instrument in the creation of corneal flaps for LASIK. Consideration of preoperative keratometric power and corneal thickness may help to reduce or avoid complications. [J Refract Surg 2002;18:149-154]
Iatrogenic Keratectasia Following Laser in situ Keratomileusis
Authors: Spadea Leopoldo , Palmieri Giampiero , Mosca Luigi , Fasciani Romina , Balestrazzi Emilio 
Published: April 2021

ABSTRACT
PURPOSE: To evaluate keratectasia after laser in situ keratomileusis (LASIK) for high myopia.
METHODS: A 49-year-old male patient with myopia of -23.50 D in both eyes underwent LASIK with a Summit Technology Apex Plus excimer laser. A Moria manually-guided MDSC microkeratome was used. Preoperative corneal topography in both eyes did not reveal underlying or fruste form of keratoconus. Four months after LASDX, a progressive keratectasia occurred in right eye and after 12 months, in left eye. Corneal transplantation was performed in both eyes.
RESULTS: Histological and ultrastructural examinations were performed on one corneal button. The analysis showed regular stromal morphology and cellularity, with no sign of inflammation. The morphometric analysis showed an overall thickness of 334 /cm, with a flap of 262 /on and a stromal residual bed of 72 ?a\, in the center of the button.
CONCLUSION: A LASIK corneal flap made with a planned 120-/tm plate turned out histologically to be approximately 260 ??\ thick, in an eye with a refractive correction of -23.50 D. The excessive flap thickness and excessive ablation produced progressive keratectasia requiring a penetrating keratoplasty. [J Refract Surg 2002;18:475-480]
The Ascent of Mount Everest Following Laser in situ Keratomileusis
Authors: Dimmig Jason W , Tabin Geoff 
Published: April 2021

ABSTRACT
PURPOSE: To report the visual experiences of climbers with prior laser in situ keratomileusis (IuASIK) for myopia at extreme altitudes, including the summit of Mount Everest.
METHODS: We measured the visual acuity of 12 LASIK eyes of 6 Mount Everest climbers at base camp (17,600 ft). Results are reported on their subjective visual experiences, as all climbers ascended above 26,000 feet and four reached the 29,035-foot summit.
RESULTS: Five of the six climbers reported no visual changes up to 26,400 feet. Three climbers noted no problems and perfect vision with their LASDX eyes on the summit of Mount Everest. One reported mild blurring with ascent above altitudes of 16,000 feet that improved with descent, or a prolonged stay at altitude. Two climbers reported blurred vision at 27,000 and 28,500 feet, respectively, which improved with descent.
CONCLUSION: Laser in situ keratomileusis may be a good choice for patients involved in high altitude activities. Patients achieving extreme altitudes of 26,000 feet and above should be aware of possible fluctuation of vision. [J Refract Surg 2003; 19:48-51]
Intraocular Pressure in Myopic Patients After Worst-Fechner Anterior Chamber Phakic Intraocular Lens Implantation
Authors: Aguilar-Valenzuela Lucrecia , Lleó-Pérez Antonio , Alonso-Muñoz Luis , Casanova-Izquierdo Joaquin , Pérez-Moltó Francisco José , Rahhal Mohamed Saleh 
Published: April 2021

ABSTRACT
PURPOSE: To assess intraocular pressure measured with a Goldmann tonometer over a period of 1 year after implantation of a Worst-Fechner anterior chamber phakic intraocular lens to correct myopia of -7.00 D or more.
METHODS: We performed a prospective, nonmasked study of 100 patients (100 myopic eyes) who had a Worst-Fechner phakic intraocular lens implanted to correct myopia of -7.00 D or greater. Central corneal Goldmann tonometry was performed before surgery and 1, 3, 6, and 12 months after surgery. The influence of different variables was assessed.
RESULTS: IOP showed a significant increase of of a mean 2.1 mmHg at 3 months after surgery (P=. 001). There was not a statistically significant difference between IOP before surgery and 6 months after PIOL implantation (P=.244) or 1 year after surgery (P=.845). In one eye, the lens was explanted 11 months after surgery because of the presence of ocular hypertension. No variables studied showed a statistically significant difference from before to after surgery.
CONCLUSIONS: Worst-Fechner anterior chamber phakic intraocular lens implantation led to a slight transitory increase of intraocular pressure during the first 3 months after surgery, but returned to preoperative levels by 6 months after implantation. [J Refract Surg 2003; 19:131-136]
Partial Flap During Laser in situ Keratomileusis: Role of Smaller Diameter Corneal Flap of Original Thickness
Authors: Fogla Rajesh , Sitalakshmi Guruswamy 
Published: April 2021

ABSTRACT
PURPOSE: To report results of smaller diameter corneal flap of original thickness in the management of partial flap during laser in situ keratomileusis (LASIK).
METHODS: Retrospective review of the case records of three patients (3 eyes) who had a partial corneal flap during LASIK.
RESULTS: Retreatment was performed using an 8.5-mm-diameter corneal flap, which was smaller than the original partial flap of 9.5-mm diameter. The reçut depth was maintained as the original cut depth of 160 µm. No intraoperative or postoperative complications were noted. At follow-up 4 weeks later, two patients had an uncorrected visual acuity of 20/20. One patient had uncorrected visual acuity of 20/40 that improved to preoperative best spectacle-corrected visual acuity of 20/30 with a correction of +0.50 -1.2? ? 170°.
CONCLUSION: A smaller diameter corneal flap of original thickness can be used for retreatment of partial flap during LASIK. A thicker posterior stromal bed after laser ablation may be retained with this technique, compared to retreatment using a corneal flap of greater thickness. [J Refract Surg 2003;19:165-168]
Safety of Laser in situ Keratomileusis Performed Under Ultra-thin Corneal Flaps
Authors: Lin Robert T , Lu Stephanie , Wang Lan Lan , Kim Elli S , Bradley Jarrod 
Published: April 2021

ABSTRACT
PURPOSE: To report on the safety of laser in situ keratomileusis (LASIK) performed under ultra-thin corneal flaps (Micro-LASIK).
METHODS: We performed a retrospective review of 1131 eyes that underwent LASIK for myopia with the Nidek MK-2000 microkeratome, and Nidek EC5000 excimer laser. The 130-/nn head and 8.5-mm ring were used in 1042 eyes and the 160-jim head and 9.5-mm ring were used in 89 eyes. For 175 eyes, intraoperative ultrasonic pachymetry was used to measure central corneal thickness and central bed thickness. Flap thickness was calculated by subtracting bed thickness prior to laser ablation from central corneal thickness. All 175 of these eyes had keratectomies using the 130-/¿m head and 8.5-mm ring.
RESULTS: At last follow-up, 455 eyes (40%) achieved 20/20 or better, 798 eyes (70%) achieved 20/25 or better, and 1077 eyes (95%) achieved 20/40 or better uncorrected visual acuity; 922 eyes (82%) achieved within 1 line of their best spectaclecorrected visual acuity. The following clinically significant complications were observed: four epithelial defects (3.5%), zero irregular flaps (0%), seven stria (0.6%), one diffuse lamellar keratitis (0.1%), one epithelial ingrowth (0.1%), and zero infections (0.0%). Two eyes (0.2%) with stria had 20/40 best spectacle-corrected visual acuity, but lost more than 2 lines of best spectacle-corrected visual acuity. The average measured flap thickness was 87.3 ± 15.4 /an.
CONCLUSION: LASIK can be performed safely under ultra-thin corneal flaps. [J Refract Surg 2003;19(suppl):S231-S236]