Rossi T.,University of Cagliari |
Rossi T.,Optikon 2000 Inc |
Querzoli G.,University of Cagliari |
Angelini G.,Optikon 2000 Inc |
And 6 more authors.
Retina | Year: 2014
PURPOSE:: To assess the efficacy of novel vitreous cutter blades compared with the regular guillotine by means of particle image velocimetry. Tested blades included a regular blade (RB) and newer designs where a circular (hole blade [HB]) or a slit aperture (slit blade [SB]) had been opened proximal to the cutting edge. METHODS:: Twenty-three-gauge probes were immersed in BSS or egg albumen, and high-speed video (1,000 frames per second) was recorded. Duty cycle, flow rate, and acceleration generated by Venturi and peristaltic pumps were measured under cutter settings simulating "low-speed" vitrectomy (1600 cuts per minute, 200 mmHg vacuum) and "high speed" vitrectomy (3000 cuts per minute, 300 mmHg vacuum). RESULTS:: The SB and HB had a significantly more favorable duty cycle than that of the RB (P < 0.01) and higher BSS flow rate regardless of the aspiration. The SB flow rate in albumen was significantly higher than that of the HB and RB only over 1,000 cuts per minute using a peristaltic pump and at any cut rate with Venturi pump (P < 0.001). The SB also yielded the lowest fluid acceleration than both the HB and SB (P < 0.001 in all cases). CONCLUSION:: The HB and SB proved to be significantly more efficient than the RB, with better duty cycle and higher flow rate. The SB generated significantly less fluid acceleration than any other tested blade, regardless of the fluid viscosity and pump technology. The SB design is significantly more efficient and possibly safer than both HB and RB. Copyright © by Ophthalmic Communications Society, Inc. Source
Rossi T.,Ospedale Oftalmico di Rome |
Querzoli G.,University of Cagliari |
Pasqualitto G.,Optikon 2000 Inc |
Iossa M.,Ospedale Oftalmico di Rome |
And 4 more authors.
Experimental Eye Research | Year: 2012
Knowledge of vitreous motion in response to saccades is a prerequisite for understanding vitreous rheology. Purpose of present paper is to introduce Ultrasound Image Velocimetry of the human eye, measure scleral and vitreous velocity fields and test the reproducibility of the proposed technique. Twelve patients with varying diagnosis underwent Ocular Dynamic Ultrasound; scleral angular velocity (V S) was measured by 2 different operators and reproducibility calculated. Squared velocity of the vitreous (E), which is representative of kinetic energy per unit mass, was computed from velocity. The time evolution of the energy of the vitreous was described by its spatial average (E S), whereas spatial distribution was described by its time average (E T). Peak and average E S, the ratio K p of the peak of the spatially averaged kinetic energy per unit mass to the maximum squared scleral angular velocity, vitreous motion onset time (T O) and vitreous motion decay time (T D) were also defined. Inter-operator reproducibility coefficient was 0.043 and correlation between operators was significant. V S, peak and average E S, K p ratio and T D differed among patients but not among operators. V S correlated with E S and T D. E S and T D but not V S, were significantly different in patients with Posterior Vitreous Detachment. Patients with retinal detachment showed significantly higher V S and E S. K p was inversely correlated to age and refraction. Measures proved accurate and reproducible. E is related to V S, retinal traction and mechanical stimulation. Identified variables varied with age, refraction pathologic conditions. © 2012 Elsevier Ltd. Source
Bandello F.,San Raffaele Scientific Institute |
Iacono P.,Fondazione G.B. Bietti |
Parodi M.B.,San Raffaele Scientific Institute
European Journal of Ophthalmology | Year: 2011
Purpose. To describe the current management of diffuse diabetic macular edema (DDME). Method s. Review and discussion of the literature regarding DDME. Results. Diffuse diabetic macular edema is a condition that can be managed by means of several treatment options, including focal/grid laser photocoagulation, intravitreal or periocular corticosteroids, intravitreal anti-vascular endothelial growth factor (VEGF), and vitrectomy with or without internal limiting membrane peeling. Conclusions. Even though there is no randomized clinical trial specifically designed to assess the best treatment approach for DDME, new therapeutic approaches based on intravitreal injections of corticosteroid and anti-VEGF molecules offer new hope for its management. © 2010 Wichtig Editore. Source
Vujosevic S.,Fondazione G.B. Bietti |
Tempesta D.,Digestive Diseases |
Noventa F.,University of Padua |
Midena E.,Fondazione G.B. Bietti |
And 3 more authors.
Hepatology | Year: 2012
Treatment with pegylated interferon alpha (PegIFNα) and ribavirin is still regarded as the standard of care for chronic hepatitis C virus (HCV). Retinopathy has been occasionally described but prospective, longitudinal data are lacking. We investigated the frequency and clinical significance of retinopathy during therapy with PegIFNα and ribavirin in 97 consecutive HCV patients. In all, 54 (55.7%) and 43 (44.3%) patients were treated with PegIFNα 2a and PegIFNα 2b, respectively. Ophthalmologic examination was performed before therapy (baseline), at 3 and 6 months (3T and 6T, respectively) of therapy, and 3 months after the end of therapy (3ET). All patients underwent the baseline and 3T examination, 95.9% and 90.7% of patients underwent 6T and 3ET examination, respectively. Overall, 30.9% of patients developed retinopathy, as defined by the presence of cotton wool spots and/or retinal hemorrhages. Variables significantly associated with retinopathy during treatment were age (P = 0.004), metabolic syndrome (P = 0.05), hypertension (P < 0.0001), cryoglobulinemia (P = 0.05), and preexisting intraocular lesions at baseline (P = 0.01). By multivariate analysis, the only variable independently associated with PegIFNα-associated retinopathy was hypertension (hazard ratio [HR] = 4.99, 95% confidence interval [CI] 2.29-10.89). The frequency of retinopathy was significantly higher in hypertensive patients versus those without hypertension at all timepoints (18.5% versus 5.7% at baseline, P = 0.05; 48.1% versus 15.7% at 3T, P = 0.0009; 68.0% versus 19.1% at 6T, P < 0.0001; 32.0% versus 6.2%, P = 0.0005 at 3ET). In one (1.1%) hypertensive patient, who developed bilateral branch retinal vein occlusion at 6T, the therapy was discontinued. A cost analysis showed that screening for PegIFNα-associated retinopathy was cost-effective as compared with thyroid-stimulating hormone screening. Conclusion: Retinopathy is frequent during treatment with PegIFNα and ribavirin, especially in hypertensive patients, who may develop serious complications. Screening for PegIFNα-associated retinopathy should be recommended for HCV patients with hypertension. © 2012 American Association for the Study of Liver Diseases. Source
Vujosevic S.,Fondazione G.B. Bietti |
Bottega E.,University of Padua |
Casciano M.,University of Padua |
Pilotto E.,University of Padua |
And 3 more authors.
Retina | Year: 2010
PURPOSE:: The purpose of this study was to evaluate and compare microperimetry and fundus autofluorescence (FAF) after subthreshold micropulse diode laser versus modified Early Treatment Diabetic Retinopathy Study photocoagulation for clinically significant diabetic macular edema. METHODS:: A prospective randomized clinical trial including 62 eyes (50 patients) with untreated, center-involving, clinically significant diabetic macular edema was performed. All patients underwent best-corrected visual acuity determination (logarithm of the minimum angle of resolution), slit-lamp biomicroscopy, FAF, optical coherence tomography, microperimetry (macular sensitivity), and fluorescein angiography before and after treatment. Best-corrected visual acuity, optical coherence tomography, microperimetry, and FAF were repeated at 1-, 3-, 6-, 9-, and 12-month follow-up examinations. Fluorescein angiography was performed at baseline and at 6 and 12 months. RESULTS:: Before treatment, demographic and macular parameters were not different between the two treatment groups. At 12 months, best-corrected visual acuity remained stable in both groups (P = 0.41 and P = 0.82), mean central retinal thickness decreased in both groups (P = 0.0002 and P < 0.0001), and mean central 4° and 12° retinal sensitivity increased in the micropulse diode laser group (P = 0.02 and P = 0.0075) and decreased in the Early Treatment Diabetic Retinopathy Study group (P = 0.2 and P = 0.0026). There was no significant difference in either best-corrected visual acuity or central retinal thickness between the 2 treatment groups (P = 0.48 and P = 0.29), whereas there was a significant difference in 4° and 12° retinal sensitivity (P = 0.04 and P < 0.0001). Fundus autofluorescence never changed in the micropulse diode laser group even after retreatment. In the Early Treatment Diabetic Retinopathy Study group, FAF increased up to 9 months and decreased in 6 eyes (20%) at 12 months. DISCUSSION:: Micropulse diode laser seems to be as effective as modified Early Treatment Diabetic Retinopathy Study laser photocoagulation in the treatment of clinically significant diabetic macular edema. Micropulse diode laser treatment does not determine any change on FAF showing (at least) nonclinically visible damage of the retinal pigment epithelium. Microperimetry data encourage the use of a new, less aggressive laser therapeutic approach in the treatment of clinically significant diabetic macular edema. Copyright © by Ophthalmic Communications Society, Inc. Source