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Uncorrected Visual Acuity (uncorrected + visual_acuity)
Selected AbstractsInfectious keratitis related to orthokeratologyOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 2 2006Xuguang Sun Abstract Purpose:, To report 28 cases of infectious keratitis related to orthokeratology lens overnight wear in China. Methods:, From March 2000 to August 2001, 28 cases of infectious keratitis related to overnight orthokeratology lens wear were diagnosed in Beijing Institute of Ophthalmology. These were retrospectively reviewed with regard to the pathogens isolated, duration of wear, the time since onset of symptoms, and age. Cultures of corneal scrapes for bacteria, fungus and Acanthamoeba were performed in all of the 28 cases. Results:, All cases were students, including 10 males and 18 females, average age was 16 years (range 10,21 years). The duration of orthokeratology overnight wearing was from 2 weeks to 2 years. Uncorrected visual acuity (UCVA) on initial examination in our institute was from 20/200 to light perception. Of 28 isolates, 24 were culture positive (including 11 bacteria, 11 Acanthamoeba and two fungi), and four were culture negative. In two of the four culture negative cases, Acanthamoeba cysts were detected in the corneal stroma with the confocal microscope. Acanthamoeba and Pseudomonas aeruginosa accounted for 75% (21 of 28) of the cases of infectious keratitis. Conclusion:, Infectious keratitis is a severe complication associated with overnight orthokeratology lens wear. Ophthalmologists should pay more attention to this complication in practice. [source] LASIK after retinal detachment surgeryACTA OPHTHALMOLOGICA, Issue 3 2006Mohsen Farvardin Abstract. Purpose:,To compare, in the same individuals, the safety and efficacy of laser in situ keratomileusis (LASIK) in eyes with and without previous retinal detachment surgery. Methods:,In a prospective clinical trial, seven myopic patients who had previously undergone scleral buckling surgery in one eye underwent conventional LASIK surgery in both eyes. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), refraction, Orbscan topography and pachymetry were recorded before and 1, 3, 6 and 12 months after surgery. The eyes were divided into two groups: group 1 consisted of eyes that had undergone previous surgery for retinal detachment, and group 2 consisted of the fellow eyes of the same patients, which had not undergone any previous ocular surgery. Student's t -test for match-paired data was used to evaluate the significance of differences. Results:,LASIK was performed successfully in all patients. The UCVA improved in all eyes in both groups. The mean change in the spherical equivalent between 1 and 12 months after LASIK surgery was 1.7 ± 1.1 and 0.6 ± 0.5 diopter in groups 1 and 2, respectively (p = 0.019). Conclusion:,LASIK may be considered for treatment of myopia in eyes that have had previous surgery for retinal detachment. However, the risk of regression may be higher in such eyes than in eyes with no previous scleral buckling surgery. [source] Clinical outcomes of corneal wavefront customized ablation strategies with SCHWIND CAM in LASIK treatmentsOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 5 2009Maria Clara Arbelaez Abstract Purpose:, To evaluate the clinical outcomes of aspheric corneal wavefront (CW) ablation profiles in LASIK treatments. Methods:, Thirty eyes treated with CW ablation profiles were included after a follow-up of 6 months. In all cases, standard examinations including preoperative and postoperative wavefront analysis with a CW topographer (Optikon Keratron Scout) were performed. Custom Ablation Manager (CAM) software was used to plan corneal wavefront customized aspheric treatments, and the ESIRIS flying spot excimer laser system was used to perform the ablations (both SCHWIND eye-tech-solutions, Kleinhostheim, Germany). Clinical outcomes were evaluated in terms of predictability, refractive outcome, safety, and wavefront aberration. Results:, In general, the postoperative uncorrected visual acuity and the best corrected visual acuity improved (p < 0.001). In particular, the trefoil, coma, and spherical aberrations, as well as the total root-mean-square values of higher order aberrations, were significantly reduced (p < 0.05) when the pre-existing aberrations were greater than the repeatability and the biological noise. Conclusions:, The study results indicate that the aspheric corneal wavefront customized CAM approach for planning ablation volumes yields visual, optical, and refractive results comparable to those of other wavefront-guided customized techniques for correction of myopia and myopic astigmatism. The CW customized approach shows its strength in cases where abnormal optical systems are expected. Apart from the risk of additional ablation of corneal tissue, systematic wavefront-customized corneal ablation can be considered as a safe and beneficial method. [source] 2146: Intracorneal lenses for the treatment of presbyopia using femtosecond laser: visual outcomes and safetyACTA OPHTHALMOLOGICA, Issue 2010IG PALLIKARIS Purpose To investigate the visual outcomes and safety of Intracorneal lenses (Flexivue Micro-Lens, Presbia, CA)) for the treatment of presbyopia. Methods This was a prospective clinical study. An intrastromal corneal tunnel was created using femtosecond laser (Intralase 150, AMO , CA). The lens was inserted within the cornea tunnel of the non-dominant eye of 10 presbiopian patients. Mean age was 51,23 years old ± 3,11 (5 males and 5 females). The follow-up was up to 12 months. Results In the operated eye, mean uncorrected visual acuity for distance (UVA-D) preoperatively, one day, one week one month, three months and six months, and 1 year after surgery was 20/20, 20/40, 20/40, 20/32, 20/32, 20/32 and 20/32 respectively, whereas for near (UVA-N) was 20/50, 20/40, 20/30, 20/30, 20/25, 20/25 and 20/30. Binocular far vision was not altered. No tissue alterations of the cornea were found using corneal confocal microscopy. No intra or post-operative complications were demonstrated up to one year after surgery. Conclusion Intracorneal lenses for the correction of presbyopia using femtosecond laser seems to be a safe and effective method to correct presbyopia in patients aged between 45 to 55 years old; a target group which is considered too old for refractive laser surgery and too young for clear lens extraction. Longer follow-up and a larger population are necessary in order to draw more significant results of this new surgical approach for the treatment of presbyopia. Commercial interest [source] Comparison of laser in situ keratomileusis reoperation outcomes with the Moria M2 head 90 and 130 following previous photorefractive keratectomy or laser in situ keratomileusisACTA OPHTHALMOLOGICA, Issue 3 2010Antti Pitkänen Abstract. Purpose:, To compare the Moria Model Two (M2) automated microkeratome with the head 90 (intended to create a 120-,m flap) to the head 130 (intended to create a 160-,m flap) in reoperations following previous photorefractive keratectomy (PRK) or laser-assisted in situ keratomileusis (LASIK) in terms of accuracy, predictability, safety and complications of the procedure. Methods:, Eighty-five eyes of 70 consecutive patients received LASIK with the Moria M2 microkeratome. Nine previously PRK-operated eyes were reoperated with the head 90 and 37 eyes were reoperated with the head 130. Repeated LASIK was performed on 16 eyes with the head 90 and on 23 eyes with head the 130. Flap dimensions were measured and correlated to preoperative parameters. Results:, The average flap thickness in the previously PRK-operated eyes was 115.1 ,m [range 82,137 ,m, standard deviation (SD) 17.9] with the head 90 and 131.2 ,m (range 105,171 ,m, SD 19.8) with the head 130. In the previously LASIK-operated eyes, the mean flap thickness was 139.2 ,m (range 92,182 ,m, SD 23.8) with the head 90 and 141.9 ,m (range 109,179 ,m, SD 15.2) with the head 130. There were no free or incomplete flaps or flaps with buttonholes in the study. There was no statistically significant difference in postoperative uncorrected visual acuity (UCVA) between the groups. Conclusion:, In eyes with previous PRK or LASIK, LASIK reoperation offers a safe alternative for improving refractive outcomes. The Moria M2 head 90, especially in LASIK-operated eyes, does not cut thinner flaps compared to the head 130. [source] Visual outcome and corneal aberrometry after implantation of intracorneal ring segments (INTACS) for keratoconusACTA OPHTHALMOLOGICA, Issue 2007J HERNANDEZ VERDEJO Purpose: To analyze corneal aberrometry and visual outcome after implantation of intracorneal ring segments (INTACS) in keratoconus patients. Methods: Corneal aberration was measured in 15 keratoconus eyes pre and post implantation of INTACS. Root Mean Square values (RMS), (Total, RMS for corneal astigmatism and RMS for coma) where recorded for 5, 6 and 7 pupil diameters, and where divided into two groups due to their previous levels of coma and total RMS. Comatic aberration was divided in vertical (Z3-1) an horizontal (Z3+1) Zernicke Coeficcients. All data was recorded pre-op and three months after surgery. Best corrected visual acuity (BCVA), uncorrected visual acuity (UCVA), spherical equivalent and astigmatism where also analyzed. Results: We found statistically significant decrease in spherical equivalent (p<0,01) and increase of UCVA (p<0,01). Significant increase (p=0,04) in coma and total RMS in patients with lower previous values for 5 and 6mm and significant decrease in patients with higher previous values for 7mm (p=0,03) Conclusions: INTACS implantation for keratoconus reduces the mean spherical refractive error, increases UCVA and improves keratoconus aberrations for 7mm pupil diameter in patients with previous high levels of coma and total RMS. [source] | ||||||||||