1,720,972 research outputs found
A 14-year follow-up of photorefractive keratectomy
No full textPurpose: To evaluate the long-term outcome of myopic photorefractive keratectomy (PRK).
Methods: This prospective study included 31 patients (49 eyes) who underwent PRK between 1991 and 1993. A Summit UV200 excimer laser was used. Patients were divided into two groups--low myopia: preoperative < 6.00 diopters (D) (range: -1.50 to -5.75 D) (n = 19); and high myopia: preoperative > 6.00 D (range: -6.00 to -13.00 D) (n = 12). Long-term postoperative follow-up was every 2 years up to 14 years. Refraction, visual acuity, corneal status, and intraocular pressure (IOP) were evaluated. At 14 years, corneal topography and endothelial cell count were performed.
Results: At last follow-up, manifest refraction spherical equivalent (MRSE) for the low myopia group was -0.17 +/- 0.8, uncorrected visual acuity (UCVA) logMAR was -0.06 +/- 0.55, and best spectacle-corrected visual acuity (BSCVA) logMAR was 0.00 +/- 1.00. The high myopia group had a final MRSE of -0.67 +/- 1.4, UCVA logMAR -0.11 +/- 0.55, and BSCVA logMAR -0.03 +/- 1.00. At 14 years, BSCVA for most eyes was at least equal to preoperative BSCVA. In both groups, haze increased between 3 and 6 months, then declined in the first year. A temporary increase of IOP was seen in 4 eyes. Complications were minor haze (2 eyes), transient anisocoria (9 eyes), and intraepithelial hemosiderin deposits (4 eyes). No abnormalities in endothelial cell count or morphology, astigmatism, or ectasia were noted. Three patients reported night vision disturbance, but the majority of patients were satisfied with the outcome based on subjective questionnaire (low myopia group: 84%; high myopia group: 75%).
Conclusions: Our study demonstrates the safety of myopic PRK
Comparison of the IOP behavior after implantation of two types of stainless steel glaucoma drainage miniature implants (Ex-Press) with different flow characteristics
No full text
Retinal blood flow autoregulation after dynamic exercise in healthy young subjects
No full textPurpose: To evaluate the retinal blood flow before and after the increase in systemic blood pressure to assess the autoregulation in healthy young subjects. Methods: Twenty eyes of 20 healthy volunteers were examined. The retinal blood flow was assessed by a Heidelberg retina flowmeter (HRF), while the systemic pressure was assessed by a portable electronic sphygmomanometer. Furthermore intraocular pressure (IOP) was always measured by a Goldmann tonometer immediately after HRF assessments. All measurements of physiological and flow parameters were performed with the subjects seated at rest and then immediately after stair climbing. Results: The IOP decreased significantly after dynamic exercise, while the heart rate and the systemic artery pressure increased significantly. At the baseline, the mean retinal blood flow was 276.8 ± 80.7 arbitrary units (AU) in the superotemporal area, 243.4 ± 63.68 AU in the superonasal area, 258.2 ± 67.37 AU in the inferotemporal area and 243.9 ± 72.24 AU in the inferonasal area. After dynamic exercise the mean retinal blood flow was 249.8 ± 86.78 AU in the superotemporal area, 248.7 ± 63.87 AU in the superonasal area, 245.4 ± 83.85 AU in the inferotemporal area and 228.8 ± 62.53 AU in the inferonasal area. No significant change in retinal blood flow was found. Conclusion: Our data support the hypothesis that in normal subjects autoregulation is sufficient to compensate the increase in blood pressure and maintain a stable retinal blood flow after exercise. Copyright © 2007 S. Karger AG
Corneal thickness and visual field damage in glaucoma patients
No full textPurpose: To verify whether there was a significant correlation between central corneal thickness (CCT) and visual field damage in patients with primary open angle glaucoma (POAG).
Methods: A total of 99 eyes with POAG were consecutively recruited. Patients were classified as glaucomatous based on visual field and optic nerve head damage. All underwent applanation tonometry, Humphrey perimetry, and measurement of CCT with ultrasonic pachymetry. Based on CCT value, the sample was split at the mode in two groups (group 1<535 microm, n=49; group 2>or=535 microm, n=50).
Results: Entire cohort: mean CCT 554 microm+/-45.03; mean deviation (MD) -6.68 dB+/-7.32; pattern standard deviation (PSD) 5.33+/-3.75; intraocular pressure (IOP) 17.91+/-4.16 mmHg with treatment. Group 1: CCT was 504.8 microm+/-30.8; MD -9.01 dB+/-8.72; PSD 6.38+/-3.99; IOP 18.02 mmHg+/-4.66. Group 2: mean CCT 574.6 microm+/-35.03; MD -4.39 dB+/-4.70; PSD 4.25+/-3.19; IOP 17.79 mmHg+/-3.57. A significant difference was found between the two groups for both MD and PSD. Linear regression analysis showed a significant correlation between CCT and PSD (P<0.001).
Conclusions: Our data show that patients with a thinner cornea had a worse MD and PSD. As a thinner CCT causes an underestimation of the true IOP, there may be a delay in the diagnosis of POAG or an inadequate estimate of the clinical course despite apparently desirable IOP applanation readings
Uso della monoterapia con Bimatoprost nella clinica quotidiana
Full text linkGli Autori riportano i risultati di uno studio multicentrico,prospettico, osservazionale condotto nel 2010 sull'uso nella pratica clinica della monoterapia con l'analogo prostanidico ,Bimatoprost 0.3 mg/ml, in pazienti con glaucoma cronico ad angolo aperto mai trattati in precedenza se non con farmaci betabloccanti
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