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Enzo Ballone

Publications and source records attributed to Enzo Ballone.

18 recordsLinked to original sources
PubMed2006

Predictors of local recurrence after conservative surgery and whole-breast irradiation.

PURPOSE: To identify independent factors associated with increased risk of local recurrence (LR) in patients with breast cancer treated with conservative surgery and radiotherapy with or without systemic therapy. METHODS AND MATERIALS: Between January 1997 and December 2001, 969 women were treated at the Radiation Oncology Department in Chieti. We retrospectively analyzed 802 of them who were treated with conservative surgery and whole breast irradiation with or without systemic therapy. Tangential fields delivering 50 Gy to the whole breast were used and a boost was added for a total dose of 60 Gy. chi(2)-test or Fisher's exact test were used to identify independent significant factors that are predictive for LR. Kaplan-Meier method was used to calculate the 8-year rates of recurrence according to age, histologic findings, tumor size, number of positive nodes, margin status, receptor status and systemic therapy use: log-rank test was used to compare these curves. Cox proportional hazard model was used to obtain hazard ratios and 95% CI of LR for each covariate. RESULTS: Median follow-up time was 63.1 months. LR occurred in 33 (4.1%) of 802 patients. Percentage of LR was greater in <50 year-olds compared with 50-64 year-olds and > or =65 year-olds (9.8% versus 4.1 and 2.0%, respectively). LR was 18.8% in women with a tumor size >3 cm versus 3.5, 4.0, 5.5% in women with a tumor size of 0.1-1, 1.1-2, 2.1-3 cm, respectively. The 8-year LR rate calculated with Kaplan-Meier method was 6.54+/-1.51. Multivariate Cox regression analysis showed that independent significant factors that are predictive for LR were: age <50, tumor size >3 cm, positive margin or unknown status, and hormonal therapy alone versus chemotherapy or combined therapy. CONCLUSIONS: Age and tumor size were the most important and statistically significant factors that correlated independently with higher rates of LR. Women <50 years old and with a tumor size >3 cm had a higher risk of LR. Also margin status and systemic therapy could influence LR risk.

Adult↗
PubMed2006

Blood pressure variability and cardiovascular risk in treated hypertensive patients.

BACKGROUND: The independent prognostic value of blood pressure (BP) variability in treated hypertension is not yet clear. We investigated the relationship between BP variability, evaluated by noninvasive monitoring, and cardiovascular outcome in treated hypertensive patients. METHODS: The occurrence of fatal and nonfatal cardiovascular events was evaluated in 1472 treated patients. Subjects with the standard deviation of daytime or night-time systolic BP below or above the median of the population were classified as having low or high BP variability. Specifically, 738 and 734 patients had low and high daytime BP variability, respectively, and 739 and 733 subjects had low and high night-time BP variability, respectively. RESULTS: During follow-up (4.88 +/- 2.9 years, range 0.2-11.6 years) there were 119 events. The event rates per 100 patient-years in subjects with low and high BP variability according to daytime BP were 1.18 and 2.01, respectively, and in those with low and high BP variability according to night-time BP were 1.2 and 2.05, respectively. Event-free survival was significantly different between the low and high BP variability groups (P = .006 for both daytime and night-time BP). However, after adjustment for other covariates in a Cox multivariate analysis, the adverse prognostic relevance of high BP variability was no longer detectable, whereas age, smoking habit, LDL cholesterol, diabetes, previous events, LV hypertrophy, and daytime or night-time systolic BP resulted independent predictors of risk. CONCLUSIONS: Increased BP variability is associated with higher incidence of cardiovascular events, but also with other relevant prognostic factors. Indeed, in multivariate analysis the possible adverse prognostic impact of BP variability is no longer evident. Thus, in treated hypertension, BP variability evaluated by noninvasive monitoring is not an independent predictor of outcome.

Aged↗
PubMed2006

Photorefractive keratectomy with aspheric profile of ablation versus conventional photorefractive keratectomy for myopia correction: six-month controlled clinical trial.

PURPOSE: To analyze ocular wavefront error and corneal asphericity (Q) in patients treated with aspheric profile photorefractive keratectomy (PRK) compared with patients having conventional PRK to correct myopia and myopic astigmatism and to evaluate the effect of postoperative corneal shape on visual performance. SETTING: Eye Clinic, University G. d'Annunzio, Chieti-Pescara, Italy. METHODS: Fifty eyes were treated with aspheric profile PRK using the MEL 80 flying-spot excimer laser, and 24 eyes were treated with standard PRK using the MEL 70 flying-spot excimer laser. RESULTS: Postoperative wavefront error increased in both groups. Six months after surgery, there was a smaller increase in root mean square (RMS) of total higher-order aberrations and spherical aberration (59% and 106%, respectively) in the aspheric profile PRK group than in the conventional PRK group (94% and 136%, respectively) (P<.01). The aspheric profile PRK group showed more prolate corneal asphericities (mean Q of 0.15 +/- 0.26) than the conventional group (mean Q of 0.45 +/- 0.26) (P<.001), with increasing oblateness for higher attempted corrections. A higher percentage of patients with better low-contrast uncorrected visual acuity and best corrected visual acuity was observed in the aspheric PRK group than in the conventional PRK group (P<.05). CONCLUSIONS: Aspheric profile and conventional PRK were safe and efficient for the correction of myopia and myopic astigmatism. Moreover, aspheric profile PRK induced a smaller increment of total wavefront error, was related to a smaller increase in spherical aberration, and better maintained the physiology of the corneal surface than conventional treatment.

Adult↗
PubMed2006

Cardiovascular risk in patients receiving double therapy with false and true nonresponder hypertension.

OBJECTIVE: The aim of this study was to evaluate cardiovascular risk in hypertensive patients receiving double therapy with false and true nonresponder hypertension. METHODS: The occurrence of fatal and nonfatal cardiovascular events was evaluated in 730 patients receiving double therapy with uncontrolled clinic blood pressure. Two hundred and seventy had false nonresponder hypertension (clinic blood pressure > or =140 or 90 mmHg and daytime blood pressure <135/85 mmHg) and 460 had true nonresponder hypertension (clinic blood pressure > or =140 or 90 mmHg and daytime blood pressure > or =135 or 85 mmHg). RESULTS: During the follow-up (4.77+/-2.9 years, range 0.2-11.7 years), 55 cardiovascular events occurred. The event rates per 100 patient-years in patients with false and true nonresponder hypertension were 1.03 and 1.9, respectively. Event-free survival was significantly different between the groups (P<0.05). After adjustment for several covariates, including clinic blood pressure (forced into the model), Cox regression analysis showed that cardiovascular risk was significantly higher in true than in false nonresponder hypertension (relative risk 2.33, 95% confidence interval 1.14-4.77, P=0.02). CONCLUSIONS: This study shows that, among treated hypertensive patients receiving double therapy with uncontrolled clinic blood pressure those with true nonresponder hypertension are at higher cardiovascular risk. Ambulatory blood pressure monitoring should be performed in this population to achieve a better prognostic stratification.

Aged↗
PubMed2006

Smoking habits in a sample of young Italian soldiers.

The aim of this cross-sectional study was to determine the attitudes and characteristics of smoking patterns in a sample of 450 young, Italian, military men. Data were collected using a self-administered questionnaire. The prevalence of military smokers was 54.4%; 45.7% of military men were smokers before enrollment, whereas 8.7% initiated smoking after enrollment. In multiple logistic regression analysis, the risk of becoming a smoker was associated with "high" cultural class of the family of origin (odds ratio [OR], 1.99; 95% confidence interval [CII, 1.05-4.23), non-nuclear family types (OR, 2.56; 95% CI, 1.25-5.25), parent (OR, 1.73; 95% CI, 1.04-2.90) and sibling/partner (OR, 2.25; 95% CI, 1.45-3.50) smokers, and >12 months of service (OR, 1.39; 95% CI, 1.07-5.43). None of the other variables relative to military status was significantly associated with smoking. Because the prevalence of military smokers was very high, we think that special programs aimed at decreasing the prevalence, with the long-term goal of smoking cessation, are needed.

Adult↗
PubMed2005

Analytical assessment of MALDI-TOF Imaging Mass Spectrometry on thin histological samples. An insight in proteome investigation.

BACKGROUND: The development of MALDI Imaging Mass Spectrometry is a promising technique in the investigation of biological molecular repertoire. We have pursued an analytical assessment of this technique in its application to proteome analysis. METHODS: A specific statistical method of analysis has been developed to enable data processing in the absence of internal standards, by defining similarity scores. RESULTS: The investigated linear mode MALDI-TOF set-up allows to obtain data variations comprised within the 30% of variation when assaying tissues samples from the same animal, while the 60% of variation was highlighted in the inter-mice series assaying syngenic animals. CONCLUSIONS: This analytical assessment represents the first step of a process that should validate the utilisation of this technique in the clinical practice.

Animals↗
PubMed2005

Screening of mutations in the CFTR gene in 1195 couples entering assisted reproduction technique programs.

Genetic testing of the cystic fibrosis transmembrane conductance (CFTR) gene is currently performed in couples undergoing assisted reproduction techniques (ART), because of the high prevalence of healthy carriers in the population and the pathogenic relationship with congenital bilateral absence of vas deferens (CBAVD). However, discordant data have been reported concerning the usefulness of this genetic test in couples with no family history of cystic fibrosis (CF). In this study, we report the results of CFTR molecular screening in 1195 couples entering ART. Genetic testing was initially carried out in a single partner of each couple. CFTR mutations were detected in 55 subjects (4.6%), a percentage that overlaps with the one reported in the general population. However, significantly higher frequencies of were found in CBAVD individuals (37.5%) and in males with nonobstructive azoospermia (6.6%). The 5T allele was found in 78 patients (6.5%). This figure was again significantly different in males with nonobstructive-azoospermia (9.9%) and in those with CBAVD (100%). All together, 139 subjects (11.6%) had either a CFTR mutation or the 5T allele. Subsequent molecular analysis of their partners disclosed a CFTR mutation or 5T allele in nine cases (6.5%). However, none of these couples had CFTR alterations in both members, a CFTR mutation being invariably present in one partner and the 5T allele in the other. In order to improve genetic counselling of these couples, the TG-M470V-5T association was analyzed, and a statistically significant relationship between 12TG-V470 and CBAVD was detected.

Alleles↗
PubMed2004

Removal of uraemic plasma factor(s) using different dialysis modalities reduces phosphatidylserine exposure in red blood cells.

BACKGROUND: Solute(s) retained during uraemia cause increased exposure of aminophospholipid phosphatidylserine (PS) on the outer surface of erythrocyte membranes, and this phenomenon may be involved in the pathophysiology of uraemia by promoting abnormal erythrocyte interactions. METHODS: We examined in a prospective randomized cross-over fashion the ability of various dialysis modalities to remove the circulating uraemic factor(s) causing increased PS externalization in red cells. Each patient was treated with haemodialysis (HD) and with on-line haemodiafiltration (HDF) using standard high-flux polysulphone membranes or with the new polisulphone-based Helixone membrane to compare the effects of dialysis technique and membrane type on PS exposure. Removal of PS was assessed indirectly by measuring PS-expressing normal erythrocytes exposed to uraemic plasma or to ultrafiltrate obtained at various time points during the extracorporeal session. RESULTS: Removal of the uraemic plasma factor(s) causing PS exposure was demonstrated by the reduced ability of uraemic plasma at the end of dialysis to induce PS exposure in normal erythrocytes, and by the capacity of ultrafiltrate from the dialysate side of the dialyzer membrane to markedly increase PS-positive red cells. However, the degree of removal varied according to the dialyzer type and to dialysis technique. Removal was greater for on-line HDF using the Helixone membrane, intermediate and comparable with HD with Helixone and with on-line HDF using standard polysulphone, and lower for HD using polysulphone membrane. The putative uraemic compound causing PS exposure seems to be highly lipophilic, somehow associated with plasma proteins, and apparently having a molecular weight between 10 and 10.8 kDa. CONCLUSIONS: Uraemia is associated with retention of compound(s) that are lipophilic, possibly protein-bound and which cause an abnormal exposure of PS in erythrocytes. Our findings, that such compound(s) can be removed during dialysis and at higher rates with convection techniques, indicate a potential benefit for uraemic patients. The present results also seem to confirm the marked ability of high-flux Helixone membranes to eliminate high molecular weight solutes.

Adult↗
PubMed2004

Analysis of the optical quality of intraocular lenses.

PURPOSE: To evaluate the optical quality of different intraocular lenses (IOLs). METHODS: An optical test bench and suitable software were used to assist in analysis of the optical Fourier transform (OFT) of a test image and to determine the quality of the lens in terms of spatial frequency response. The OFT was automatically converted, by means of an optical-electronic calibration procedure, into a modulation transfer function (MTF) for each lens. The passband value calculated by computer analysis of the MTF is an objective index of the lens quality. Three randomly acquired samples of 24 different models of foldable IOLs were compared. Statistical analysis was performed with two-way and one-way ANOVA for repeated measurements and with the Ryan-Einot-Gabriel-Welsch multiple F test. RESULTS: The method was demonstrated to be precise and accurate. A large range of passband values was found. Statistically significant differences between the mean passband values for different lenses were found. The lowest passband value (125.60 line pairs [lp]/mm) was measured for the IOL (Lenstec LH3000; Lenstec, Inc., St. Petersburg, FL) and the highest (191.48 lp/mm) for the Acrysof SA30AL (Alcon, Fort Worth, TX). CONCLUSIONS: Different IOLs can transmit different spectra of spatial frequencies. The best frequency response was provided by acrylic IOLs, particularly those with an asymmetrically biconvex profile. This could be due to a reduction of optical degradation provided by this type of profile. A lens with a higher frequency response should determine a better quality of vision once implanted and the frequency response should therefore be considered when choosing the intraocular lens model.

Fourier Analysis↗
PubMed2003

Probabilistic approach to developing nephropathy in diabetic patients with retinopathy.

It is well known that diabetes is a risk factor for many complications including diabetic retinopathy and nephropathy. An interesting question is whether a diabetic patient who has developed a retinopathy develops a nephropathy sooner. We approached this problem by calculating the conditional probability that a diabetic patient will develop a second complication, given that they had already developed the first complication. We also propose the application of Bayes' formula to estimate the probability of developing the second complication, given that the first complication had developed previously. We compared these two methods by applying them to analyse 5473 patients with type 2 diabetes. The results of our experience are described.

Adult↗
PubMed2003

Hydrophobic acrylic versus heparin surface-modified polymethylmethacrylate intraocular lens: a biocompatibility study.

BACKGROUND: The implant of intraocular lenses (IOLs) following cataract surgery induces a foreign-body reaction to the IOL and a response on the part of the lens epithelial cells (LECs). The purpose of this study was to compare these aspects after the implantation of two different IOL materials. METHODS: Thirty-six cataract patients were randomised to receive two different foldable lens: an acrylic hydrophobic IOL (Acrysof MA30BA) and a heparin surface-modified (HSM) polymethylmethacrylate IOL (Pharmacia & Upjohn 809C) after phacoemulsification. Slit-lamp biomicroscopy with specular technique was used to assess the inflammatory cell adhesion on the anterior IOL surface, anterior capsule opacification (ACO) and membrane growth from the rhexis edge at 7, 30, 90, 180 and 360 days after surgery. RESULTS: The 809C group showed a higher percentage of patients with slight inflammatory cell adhesion on the anterior cell surface and a higher small cellular density during the whole follow-up period. The epithelioid cell response was greater in the 809C group than the Acrysof group but the difference between the two groups was not statistically significant. The ACO increased during the follow-up in both groups but was significantly higher in the 809C group. CONCLUSION: Acrysof lenses are more biocompatible than HSM IOLs, showing a lower grade of inflammatory cell adhesion and ACO. The implantation of these lenses may be particularly indicated in patients with pathologies predisposing to blood-aqueous barrier damage.

Acrylates↗
PubMed2003

Clinical study of the 1CU accommodating intraocular lens.

PURPOSE: To compare the near functional capacities of patients with an accommodating intraocular lens (IOL) with those of patients with a conventional monofocal IOL. SETTING: Department of Ophthalmology, University of Chieti, Chieti, Italy. METHODS: This prospective double-blind case-control study comprised 42 eyes that had phacoemulsification and implantation of 1 of 2 types of IOLs: HumanOptics accommodating 1CU(R) (study group) and Eurocrystal IFP 3G 6.00 (control group). The main outcome measures were subjective refraction, uncorrected distance acuity, best corrected distance acuity, distance corrected near acuity at 40 cm, best corrected near acuity at 40 cm, and subjective amplitude of accommodation. Patients were examined 7, 30, 90, and 180 days after surgery. RESULTS: Postoperatively, both groups had excellent uncorrected distance acuity, best corrected distance acuity, and best corrected near acuity. In the study group, the mean distance corrected near acuity (Jaeger) was 5.43 +/- 0.98 (SD) (range 4 to 7) at 7 days, 2.33 +/- 0.48 (range 2 to 3) at 1 and 3 months, and 3.66 +/- 2.12 (range 2 to 7) at 6 months. In the control group, the mean distance corrected near acuity was 7.43 +/- 0.50 (range 7 to 8) during the entire follow-up. The differences between the groups was statistically significant (P<.001). The mean amplitude of accommodation was 0.00 diopter (D) in the control group and 1.14 +/- 0.44 D (range 0.75 to 2.00 D) in the study group at 7 days, 2.36 +/- 0.28 D (range 2.00 to 2.75 D) at 30 and 90 days, and 1.90 +/- 0.77 D (range 0.75 to 2.75 D) at 6 months. CONCLUSIONS: The 1CU accommodating IOL provided better useful spectacle-free near visual acuity than the conventional monofocal IOL. However, the accommodating mechanism can play a role in capsule fibrosis.

Aged↗
PubMed2003

Association between serum leptin levels and 24-hour blood pressure in obese women.

OBJECTIVE: To assess the relationship between serum leptin and 24-hour blood pressure (BP) in obese women, according to body fat distribution. RESEARCH METHODS AND PROCEDURES: A cross-sectional study was carried out in a population of 70 nondiabetic, normotensive, obese women (40 with android and 30 with gynoid type of obesity) and 20 nonobese healthy women as a control group. All subjects underwent 24-hour ambulatory BP monitoring. Blood samples were collected for serum leptin and plasma insulin measurements. Total cholesterol and high-density lipoprotein cholesterol were also measured. RESULTS: Serum leptin levels were significantly higher in obese subjects than in controls, and they were more elevated in android obese women than in gynoid ones. Leptin levels were positively related to body mass index (BMI), insulin, and waist and hip circumferences in the android group. Among gynoid subjects, leptin levels showed positive associations with BMI and insulin. In women with android obesity, strong positive correlations (p < 0.001) were found between leptin levels and 24-hour systolic BP (SBP), daytime SBP, nighttime SBP, 24-hour diastolic BP (DBP), and daytime DBP. Multiple regression analyses, including age, insulin and leptin concentrations, BMI, and waist and hip circumferences on 24-hour and daytime SBP and DBP, showed that only leptin levels contributed to the variability of BP. CONCLUSIONS: Our study shows that serum leptin levels are directly related to 24-hour BP levels in normotensive women with android fat distribution, independently of BMI.

Adult↗
PubMed2002

Biocompatibility of hydrophilic intraocular lenses.

PURPOSE: To assess the biocompatibility of 3 hydrophilic acrylic intraocular lenses (IOLs) by evaluating the postoperative cell reaction on the IOL surface, anterior capsule opacification (ACO) rate, and presence of membrane growth over the anterior IOL surface. SETTING: University Eye Clinic of Trieste, Trieste, Italy. METHODS: In this prospective study, 73 patients were randomized to receive 1 of 3 types of hydrogel IOLs after phacoemulsification: Storz Hydroview H60M, Corneal ACR6D, or Ioltech Stabibag. To analyze and photograph the anterior IOL surface, slitlamp biomicroscopy and specular microscopy were performed 7, 30, 90, and 180 days after surgery. Small, epithelioid, and giant inflammatory cell reaction was evaluated. In addition, ACO and membrane growth on the anterior IOL surface were assessed. RESULTS: Low inflammatory cell adhesion was observed on the anterior surface of all 3 IOLs. The Stabibag group had a significantly higher grade of small inflammatory cell reaction 7 and 30 days after surgery. A significantly higher rate of ACO was observed in the ACR6D group. The Hydroview and ACR6D groups had a significantly higher percentage of membrane growth from the capsulorhexis edge onto the anterior IOL surface than the Stabibag group. CONCLUSIONS: Clinically, the 3 hydrophilic IOLs behaved in a different manner, showing the different forms of biocompatibility. Results indicate that a different chemical composition determines correspondingly different protein absorption on IOL surfaces. This might result in a different adhesion pattern and spreading of lens epithelial and inflammatory cells.

Acrylic Resins↗
PubMed2002

Comparison of Etest, agar dilution, broth microdilution and disk diffusion methods for testing in vitro activity of levofloxacin against Staphylococcus spp. isolated from neutropenic cancer patients.

The susceptibility to levofloxacin of 194 consecutive staphylococcal (45 Staphylococcus aureus and 149 coagulase-negative staphylococci) isolates from neutropenic patients was determined by Etest and the results compared with those obtained using NCCLS-methods (broth microdilution, agar dilution and disk diffusion). Overall agreement at +/- 1log(2) dilution for Etest compared with broth microdilution and agar dilution was 99.0 and 83.5%, respectively. The Etest category agreement with broth microdilution and disk diffusion was 95.9 and 89.7%, respectively. Comparison of categories with Etest and agar dilution method gave only 67.0% absolute categorical agreement, with 29.9% minor errors and 10.7% major errors. No very major errors occurred by the four methods tested. Our results show that Etest is a valid alternative to the reference NCCLS-methods for monitoring the clinical usefulness of levofloxacin against staphylococci isolates from neutropenic patients.

Agar↗
PubMed2002

Platelet activation markers in patients with nephrotic syndrome. A comparative study of different platelet function tests.

BACKGROUND/AIM: Enhanced platelet reactivity may play a significant role in the genesis of the hypercoagulable state of nephrotic syndrome. However, the role of platelet function testing in nephrosis is controversial, partly because the methods used to assess platelet function (platelet aggregation and immunoassays of plasma beta-thromboglobulin and platelet factor 4) have such marked methodological problems. In the present study, we evaluated several tests assessing platelet function in 18 adult patients with idiopathic nephrotic syndrome and normal renal function. METHODS: Platelet function was assessed by measurement of plasma beta-thromboglobulin (enzyme-linked immunosorbent assay, ELISA), plasma P-selectin (ELISA), circulating platelets exposing the activation-dependent antigens P-selectin (CD62P) and lysosomal GP53 (CD63) (flow cytometry), and by aggregation response to agonists such as ADP and collagen. Results were compared to those obtained in a group of 16 age- and gender-matched healthy subjects. RESULTS: Levels of plasma beta-thromboglobulin (p = 0.001), plasma P-selectin (p < 0.001), and CD62P/CD63-positive platelets (p < 0.001 for both) were increased in nephrotic patients as compared to healthy controls. Platelet hyperaggregability in vitro was found in 13/18 patients. The reproducibility of platelet activation markers, as assessed by blood sample collection a week later from all patients, was found to be higher for plasma P-selectin (Spearman correlation coefficient, R = 0.99) and circulating activated platelets (CD62P: R = 0.97; CD63: R = 0.96) than for plasma beta-thromboglobulin (R = 0.78). CONCLUSIONS: Pronounced platelet activation takes place in nephrotic syndrome and may contribute to the hypercoagulability of nephrosis. Whole blood flow cytometry assay of platelet activation and plasma P-selectin assay may represent useful tests to assess the hypercoagulable state in nephrotic patients.

Adult↗
PubMedDate not supplied

Prospective randomized comparison of wavefront-guided and conventional photorefractive keratectomy for myopia with the meditec MEL 70 laser.

PURPOSE: To study refractive results and aberrometric changes in myopic patients treated with wavefront-guided photorefractive keratectomy (PRK) in comparison with standard PRK. METHODS: Sixty eyes of 60 patients with myopic astigmatism were randomly divided into two groups. Group 1 included 30 eyes (mean spherical equivalent refraction -4.39 +/- 1.31 D; range -2.50 to -6.50 D) treated with wavefront-guided PRK using the WASCA workstation and the Asclepion Meditec flying spot MEL 70 excimer laser. Group 2 had 30 eyes (mean spherical equivalent refraction -4.33 +/- 1.22 D; range -2.50 to -6.50 D) that underwent conventional PRK using the same laser, and served as the control group. Wavefront analysis of high order aberrations was performed before and 6 months after surgery. RESULTS: Postoperatively, wavefront error increased in both groups (5.0-mm wavefront aperture diameter). Six months after surgery, the eyes that received the WASCA ablation had a smaller increase in root-mean-square (RMS; 70% of increment) compared to the conventional PRK group (139% of increment) (P<.001). In the standard PRK group, all aberrations notably increased; in the wavefront-guided PRK group there was a smaller increase of trefoil and spherical aberrations (P<.001) and a decrease of coma aberrations (P<.001). The smaller increase of wavefront error in the wavefront-guided PRK group compared to the standard PRK group was more evident when preoperative RMS values were higher than 0.4 microm (P<.01). The visual parameters (spherical equivalent refraction, uncorrected and best spectacle-corrected visual acuity) did not show significant differences between the two groups. CONCLUSION: Wavefront-guided PRK induced a smaller increase of postoperative wavefront-error compared to conventional PRK, particularly in patients with higher preoperative higher order aberrations.

Adult↗