Tommaso Rossi - Academia.edu (original) (raw)

Papers by Tommaso Rossi

Case Medical Research, 2019

To report closure rate, Best Corrected Visual Acuity (BCVA), Retinal Sensitivity (RS) and Fixatio... more To report closure rate, Best Corrected Visual Acuity (BCVA), Retinal Sensitivity (RS) and Fixation Stability (FS) of idiopathic Macular Holes (MH) randomized to Cover Group (CG) or Fill Group (FG) of the Inverted Internal Limiting Membrane (ILM) flap surgical procedure. Twenty-eight patients were randomized (1:1) to receive a vitrectomy with either Cover or Fill ILM flap technique. All patients underwent BCVA, RS and FS assessment at baseline, 1-month and 3-months after surgery. MH closed in all patients. BCVA rose from 20/100 (baseline) to 20/33 (1-month) in both groups, to 20/28 in CG versus 20/33 in FG (3-months) (p < 0.05). The central 4° RS rose from 11.5 and 12 dB to 19 and 19.5 dB (1-month) and to 22 and 20 dB (3-months), respectively, in CG and FG (p < 0.001). The central 10° RS rose from 11 and 15 dB to 22 and 20 dB (1-month) and to 23 and 20 dB (3-months), respectively, in CG and FG (p < 0.001). FS increased significantly more in CG. CG improved significantly more than FG in terms of BCVA, RS and FS. The average MH diameter was relatively small (397 µm);

British Journal of Ophthalmology, 2018

PurposeTo review a series of highly myopic eyes with retinal detachment undergoing pars plana vit... more PurposeTo review a series of highly myopic eyes with retinal detachment undergoing pars plana vitrectomy with autologous internal limiting membrane (ILM) flap placed over posterior retinal breaks located in areas of choroidal atrophy.MethodsRetrospective review of 13 consecutive patients receiving pars plana vitrectomy with ILM flap over causative breaks, compared with 19 controls receiving the same surgery with ILM peeling but no ILM flap. Main outcome measures included anatomical success rate, visual acuity, number of surgeries and the rate of silicone oil removal.ResultsPatients in the ILM group required 2.08±0.37 interventions versus 2.58±0.75 in the control group (p=0.037). One (1/13; 7.6%) patient in the ILM group required additional unplanned surgery versus 8/19 (42.10%) in the control group (p=0.038). Final anatomical success rate defined as attached retina after silicone oil (SiO) removal was 13/13 in the I-ILM group and 14/19 (73.6%) in the control group (p=0.052). No pati...

PurposeOxidative damage to the trabecular meshwork (TM) represents one of the pathogenic mechanis... more PurposeOxidative damage to the trabecular meshwork (TM) represents one of the pathogenic mechanisms leading to primary open angle glaucoma (POAG). Glutathione S-transferase mu 1 (GSTM1) may neutralizes reactive oxygen species protecting the TM. The present paper investigates the prevalence of GSTM1 null genotype in an Italian population, and its association with POAG treated either medically or surgically.MethodsIn a case-control study, the GSTM1 genotype was identified in POAGs and controls. The POAGs patients were divided in two groups: medical POAGs and surgical POAGS. Medical POAGs consisted of patients with a well-controlled intraocular pressure (IOP) by IOP-lowering medications and a stable visual field (VF). Patients with an uncontrolled IOP and a progressing VF that were submitted to incisional surgery formed the surgical POAGs’ group.ResultsWe enrolled 104 medical POAGs, 158 surgical POAGs and 263 Controls. No significative differences between the groups existed regarding a...

European Journal of Ophthalmology, 2019

Background:The purpose of this study is to determine the prevalence of diabetes and diabetic macu... more Background:The purpose of this study is to determine the prevalence of diabetes and diabetic macular edema in patients undergoing senile cataract surgery in Italy.Methods:It is a prospective, multicenter, cross-sectional study. Thirteen ophthalmic units equally distributed across the Italian territory have been involved in the study. For a period of 3 months, all subjects undergoing phacoemulsification received an Optical Coherence Tompgraphy (OCT) scan and were screened for the anamnestic presence of diabetes. In addition, five selected units collected blood samples from all their patients to measure glycated hemoglobin (HbA1c) levels and detect the presence of occult diabetes (HbA1c > 6.5%). In diabetic patients, levels of retinopathy were measured and diabetic macular edema was considered significant (clinically significant macular edema) when foveal thickness was above 30% of normal levels.Results:A total number of 3657 subjects have been screened. Among them, 20.4% were diab...

Experimental Eye Research, 2018

Purpose of present study is to evaluate if the Pre-Macular Bursa (PMB) modifies Wall Shear Stress... more Purpose of present study is to evaluate if the Pre-Macular Bursa (PMB) modifies Wall Shear Stress (WSS) at the retinal surface during saccadic movements. We created a 25,000 cells mathematical in order to calculate WSS throughout the retinal surface. The posterior pole was divided into 3 zones comprising 400 nodes each. Zone 1 (radius 3.5mm; 0°-17°) corresponding to the PMB area; zone 2 (concentric annular area 5 mm in radius; 22°) and zone 3 (concentric annular area 5.5 mm; 28°). The saccade covered 50° in 0.17s. Recording time was 0.34 s. The PMB reduced WSS significantly at the macula and increased it in the immediate surroundings. Average WSS in zone 1 was 1.53 ± 1.01 (max 4.23 Pa) with PMB Vs 6.94 ± 9.23 (max 35.83 Pa) without; in zone 2 was 9.39 ± 10.33 (max 48.36 Pa) with PMB Vs 6.95 ± 9.40 (max 38.60 Pa) without while in zone 3 was 8.41 ± 10.03 (max 43.16 Pa) with PMB Vs 6.88 ± 9.42 (max 39.43 Pa) without. p<0.001 in all cases. The PMB significantly reduces WSS over the retinal surface underlying the bursa region; conversely, WSS slightly increases it in the immediate neighboring areas.

Neurology - Neuroimmunology Neuroinflammation, 2020

In the Clinical/Scientific Note "Acute disseminated encephalomyelitis after SARS-CoV-2 infection"... more In the Clinical/Scientific Note "Acute disseminated encephalomyelitis after SARS-CoV-2 infection" by Novi et al., 1 there is an error in the opening paragraph. The first sentence should read, "Acute disseminated encephalomyelitis (ADEM) is a rare autoimmune disease of the CNS, that often develops after viral infections and mainly affecting children." The publisher regrets the error.

Acta medica Okayama, 2017

Parafoveal retinal holes (PRHs) are one of the complications that can occur after internal limit... more Parafoveal retinal holes (PRHs) are one of the complications that can occur after internal limiting membrane (ILM) peeling during macular surgery. Here we describe a patient in whom an exceptionally large PRH (1,069-μm dia.) was successfully closed by repeated autologous ILM transplantation.

Modeling and Artificial Intelligence in Ophthalmology, 2019

Purpose: Intraocular pressure (IOP) during pars plana vitrectomy (PPV) decreases as aspiration ge... more Purpose: Intraocular pressure (IOP) during pars plana vitrectomy (PPV) decreases as aspiration generates flow, a phenomenon known as head loss. Since direct measurement of the IOP during surgery is impractical, currently, available compensating systems infer IOP by measuring infusion flow rate and estimating corresponding pressure drop. The purpose of the present paper is to propose and validate a physically based algorithm of the infusion pressure drop as a function of flow. Methods: Complete infusion lines (20G, 23G, 25G and 27G) were set up and primed. The infusion bottle was set at incremental heights and flow rate measured 10 times and recorded as mean Å} SD. Overall head loss (OHL) was defined, according to hydraulics laws, as the sum of frictional head loss (FHL; i.e., pressure drop due to friction along tubing) and exit head loss (EHL). The latter is equal to the kinetic energy of the exiting flow through the trocar (FKE = V2/2g). A 2nd degree polynomial equation (i.e., ΔP =...

Investigative Opthalmology & Visual Science, 2011

PURPOSE. To test the hypothesis that blunt trauma shockwave propagation may cause macular and per... more PURPOSE. To test the hypothesis that blunt trauma shockwave propagation may cause macular and peripheral retinal lesions, regardless of the presence of vitreous. The study was prompted by the observation of macular hole after an inadvertent BB shot in a previously vitrectomized eye. METHODS. The computational model was generated from generic eye geometry. Numeric simulations were performed with explicit finite element code. Simple constitutive modeling for soft tissues was used, and model parameters were calibrated on available experimental data by means of a reverse-engineering approach. Pressure, strain, and strain rates were calculated in vitreous-and aqueous-filled eyes. The paired t-test was used for statistical analysis with a 0.05 significance level. RESULTS. Pressure at the retinal surface ranged between Ϫ1 and ϩ1.8 MPa at the macula. Vitreous-filled eyes showed significantly lower pressures at the macula during the compression phase (P Ͻ 0.0001) and at the vitreous base during the rebound phase (P ϭ 0.04). Multiaxial strain reached 20% and 25% at the macula and vitreous base, whereas the strain rate reached 40,000 and 50,000 seconds Ϫ1 , respectively. Both strain and strain rates at the macula, vitreous base, and equator reached lower values in the vitreous-compared with the aqueous-filled eyes (P Ͻ 0.001). Calculated pressures, strain, and strain rate levels were several orders of magnitude higher than the retina tensile strength and load-carrying capability reported in the literature. CONCLUSIONS. Vitreous traction may not be responsible for blunt trauma-associated retinal lesions and can actually damp shockwaves significantly. Negative pressures associated with multiaxial strain and high strain rates can tear and detach the retina. Differential retinal elasticity may explain the higher tendency toward tearing the macula and vitreous base. (Invest

Translational Vision Science & Technology, 2020

To assess whether the use of a patented, novel feedback device intended to accurately control pha... more To assess whether the use of a patented, novel feedback device intended to accurately control phacoemulsification tip elongation is effective under varying machine settings and material resistance. Methods: Sculpt mode phaco (550-mm Hg Venturi pump; elongations, 35 and 70 μm) and quadrant settings (550-mm Hg Venturi pump; elongations, 15, 30, and 60 μm) were used in agar gel of incremental density (1%, 2%, 3%, and 6% in demineralized water). Dispersed lens fragments were also simulated with 6% agar gel spherules (2-5 mm in diameter; 550-mm Hg vacuum, and 60-μm elongation). Actual phaco tip elongation was measured on voltage readings from the piezoelectric crystals and compared to nominal elongation with feedback control off and on. Results: Mismatch between nominal and actual elongation when feedback control was off in sculpt mode varied between-13.51 μm and-23.07 μm of nominal elongation; in quadrant mode, mismatch varied between-2.79 μm and-20.41 μm. When the feedback control system was switched on, mismatch varied between-0.02 μm and +0.43 μm (P < 0.001 for all matchings). When the feedback system was off, the elongation mismatch among the 1%, 3%, and 6% agar was also statistically significant (P < 0.001). Elongation was 44.72 ± 4.16 μm with feedback control off and 60.02 ± 1.63 μm with it on (nominal elongation 60 μm; P < 0.001) when emulsifying agar 6% gel fragments. Dispersion of elongation data was also significantly wider when feedback control was turned off. Conclusions: A novel feedback control system effectively controls elongation accuracy regardless of the resistance offered by incremental agar gel concentrations. Translational Relevance: Implementing feedback control in phaco handpieces dramatically improves surgical accuracy. The translational value of this research relies on its immediate applicability to routine cataract surgery, resulting in a more appropriate use of ultrasound energy.

Graefe's Archive for Clinical and Experimental Ophthalmology

BMJ Open Ophthalmology

ObjectiveTo report the results of a global survey on cataract practice patterns related to preope... more ObjectiveTo report the results of a global survey on cataract practice patterns related to preoperative, intraoperative and postoperative care, surgical setting and personnel allocation.Methods and analysisAn online 28 questions survey was sent to 240 ophthalmologists asking to describe prevailing trends in their institutions across 38 countries and 5 continents. Questions inquired country, institution, surgical volume and setting, anaesthesia, preoperative and intraoperative examination and postsurgical care. Statistical analysis used crosstabs lambda statistics for non-parametric nominal variables. P value less than 0.05 was considered statistically significant.Results209/240 (87%) ophthalmologists responded: 38% representing public hospitals, 36% private practices and 26% academic sites; overall surgical volume was between 241 700 and 410 500 cataracts per year. There was a significant correlation between type of institution and surgical volume. Complete results available in onli...

Journal of Clinical Medicine

Purpose is to review the pathogenic mechanism for ocular hypertension and glaucoma development af... more Purpose is to review the pathogenic mechanism for ocular hypertension and glaucoma development after pars plana vitrectomy. Both acute and chronic causes are considered, and special attention is paid to the theories and clinical evidence on the risk of developing Open Angle Glaucoma (OAG) after Pars Plana Vitrectomy (PPV). Most existing scientific literature on the issue agree on the role of ascorbate as an oxygen scavenger within the vitreous chamber. Oxygen tension in the vitreous and anterior chamber is maximum inn proximity of the retinal surface and endothelium, respectively and steeply decreases toward the lens, on both sides, and trabecular meshwork. Vitreous removal and, to a lesser extent, liquefaction, greatly reduces oxygen tension gradient in vitreous chamber while cataract extraction has similar effects on anterior chamber oxygen gradients. Oxygen derivatives originated from the cornea and retina are actively reduced by the vitreous gel and/or the crystalline lens. Vitr...

Graefe's Archive for Clinical and Experimental Ophthalmology

Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie, Jan 4, 2017

To compare the anatomic and functional outcome of two variants of the inverted internal limiting ... more To compare the anatomic and functional outcome of two variants of the inverted internal limiting membrane (I-ILM) flap technique for idiopathic macular holes (IMH) larger than 400 µm. Twenty-seven consecutive patients undergoing PPV for IMH were randomly assigned to different variants of I-ILM technique: the Cover group included 14 patients in which the I-ILM was folded upside-down over the MH as a single layer while the Fill group enrolled 13 patients in which the I-ILM was folded within the MH in multiple layers. MH closed in 12/14 Cover and in 13/13 Fill eyes (84.6 vs. 100%, p = 0.14; n.s.). Vision at 1 month was Snellen 0.44 ± 0.17 vs. 0.28 ± 0.21 (p = 0.05) and 0.48 ± 0.20 vs. 0.37 ± 0.25 (n.s.) at 3 months. IS/OS line interruption width was 463 ± 385 vs. 602 ± 210 µm, respectively, at 1 month (n.s.) and 602 ± 210 vs. 563 ± 209 µm at 3 months (n.s.). The Cover group showed outer retina cystic changes more often (p < 0.01). MH over 700 µm closed in 0/2 and in 2/2 cases, respe...

Translational vision science & technology, 2016

To measure the hydraulic resistance (HR) of vitreous cutters equipped with a Regular guillotine B... more To measure the hydraulic resistance (HR) of vitreous cutters equipped with a Regular guillotine Blade (RB) or double edge blade (DEB) at cut rates comprised between 0 and 12,000 cuts per minute (CPM) and compare it with vitreous fragment size. This was an in vitro experimental study; in vivo HR measure and vitreous sampling. HR, defined as aspiration pressure/flow rate, was measured in balanced salt solution (BSS; Alcon, Fort Worth, TX) (in vitro) and during pars plana vitrectomy of 20 consecutive patients aged 18 to 65, undergoing macular surgery. HR was recorded at increasing cut rates (500-6000 CPM for the RB and 500-12,000 CPM for the DEB; 5 mL/min flow). Vitreous samples were withdrawn and analyzed with Western and collagen type II and IX immunostaining to evaluate protein size. The main outcome measures were hydraulic resistance (mm Hg/ml/min [±SD]) and optic density for Western blot and immunostaining. RB and DEB showed identical HR in BSS between 0 and 3000 CPM. Above 3000 C...

Retinal Cases Brief Reports, 2007

Wolters Kluwer Health may email you for journal alerts and information, but is committed to maint... more Wolters Kluwer Health may email you for journal alerts and information, but is committed to maintaining your privacy and will not share your personal information without your express consent. For more information, please refer to our Privacy Policy. ... Skip Navigation Links Home &gt; Spring ...

Retina J Retin Vitr Dis, 1997

The purpose of this study was to estimate if and to what extent scanning laser ophthalmoscopy can... more The purpose of this study was to estimate if and to what extent scanning laser ophthalmoscopy can help in the early diagnosis and follow-up management of the vitreoretinal interface syndrome, which includes disorders such as cellophane maculopathy, pseudomacular hole, macular pucker, and macular hole. The 35 fellow eyes of 35 patients with vitreoretinal interface syndromes in the first eye underwent scanning laser ophthalmoscopy microperimetry and argon, helium-neon, and infrared scanning laser ophthalmoscopy. Fellow eyes were defined as clinically positive or negative for vitreoretinal interface syndrome. Fellow eyes then were classified based on scanning laser ophthalmoscopy techniques. Patients were observed for an average of 18 months (range, 10-26 months). Thirty-two of the 35 fellow eyes were classified as clinically negative, and three of the 35 were classified as clinically positive. Fifteen of the 32 clinically negative fellow eyes were redefined as positive on scanning laser ophthalmoscopy. None of the clinically positive eyes proved to be negative on scanning laser ophthalmoscopy. During the average follow-up period (18 months), the condition of five of 18 fellow eyes that were positive on scanning laser ophthalmoscopy worsened. None of the 17 eyes that were negative on scanning laser ophthalmoscopy worsened. Scanning laser ophthalmoscopy can produce beautifully clear images of structures that are otherwise difficult to see and document, such as posterior hyaloid and the inner retinal layers. Despite a relatively limited number of cases and the short duration of the follow-up period, the present study suggests that scanning laser ophthalmoscopy has good sensitivity and specificity for the early diagnosis of vitreoretinal interface syndromes.

Retina, 2015

To characterize the fluidics of axial rotating vitreous cutter probe (RT) compared with the stand... more To characterize the fluidics of axial rotating vitreous cutter probe (RT) compared with the standard guillotine (regular blade), when tested in Balanced Salt Solution (Alcon Laboratories, Forth Worth, TX). RT and regular blade (RB) cutter probes connected to the same vitrectomy console used a peristaltic pump. The authors measured instantaneous flow through aspiration tubing proximal to the handpiece, fluid velocity, and acceleration at the port by means of particle image velocimetry. Average flow at aspiration tubing of RT and RB did not vary significantly. Regular blade probes produced higher instantaneous flow fluctuation than RT at any considered cut rate (RB 1,600 6.4 ± 5.3 mL/minute; RB 3,000 11.8 ± 6.3 mL/minute; RT 1,600 0.9 ± 0.7 mL/minute, and RT 3,000 1.8 ± 0.8 mL/minute, respectively. P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001 in all cases). Regular blade also yield significantly higher fluid velocity at cutter port compared with RT (RB 1,600 85.8 ± 70.1 mm/second; RB 3,000 81.6 ± 66.4 mm/second; RT 1,600 71.9 ± 40.3 mm/second; and RT 3,000 32.9 ± 20.8 mm/second. P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001 in all cases). Fluid acceleration at the cutter port was higher when the RB was used (RB 1,600 26.85 ± 30.18 mm/second; RB 3,000 33.76 ± 34.09 mm/second; RT 1,600 24.01 ± 21.94 mm/second; and RT 3,000 16.62 ± 17.87 mm/second. P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001 in all cases). RT blade design causes less instantaneous flow fluctuation within the aspiration tubing, and also lower fluid velocity and lower acceleration at the cutter port. Fluidics suggests a safer cutting action and a reduced risk of retinal incarceration.

Case Medical Research, 2019

To report closure rate, Best Corrected Visual Acuity (BCVA), Retinal Sensitivity (RS) and Fixatio... more To report closure rate, Best Corrected Visual Acuity (BCVA), Retinal Sensitivity (RS) and Fixation Stability (FS) of idiopathic Macular Holes (MH) randomized to Cover Group (CG) or Fill Group (FG) of the Inverted Internal Limiting Membrane (ILM) flap surgical procedure. Twenty-eight patients were randomized (1:1) to receive a vitrectomy with either Cover or Fill ILM flap technique. All patients underwent BCVA, RS and FS assessment at baseline, 1-month and 3-months after surgery. MH closed in all patients. BCVA rose from 20/100 (baseline) to 20/33 (1-month) in both groups, to 20/28 in CG versus 20/33 in FG (3-months) (p < 0.05). The central 4° RS rose from 11.5 and 12 dB to 19 and 19.5 dB (1-month) and to 22 and 20 dB (3-months), respectively, in CG and FG (p < 0.001). The central 10° RS rose from 11 and 15 dB to 22 and 20 dB (1-month) and to 23 and 20 dB (3-months), respectively, in CG and FG (p < 0.001). FS increased significantly more in CG. CG improved significantly more than FG in terms of BCVA, RS and FS. The average MH diameter was relatively small (397 µm);

British Journal of Ophthalmology, 2018

PurposeTo review a series of highly myopic eyes with retinal detachment undergoing pars plana vit... more PurposeTo review a series of highly myopic eyes with retinal detachment undergoing pars plana vitrectomy with autologous internal limiting membrane (ILM) flap placed over posterior retinal breaks located in areas of choroidal atrophy.MethodsRetrospective review of 13 consecutive patients receiving pars plana vitrectomy with ILM flap over causative breaks, compared with 19 controls receiving the same surgery with ILM peeling but no ILM flap. Main outcome measures included anatomical success rate, visual acuity, number of surgeries and the rate of silicone oil removal.ResultsPatients in the ILM group required 2.08±0.37 interventions versus 2.58±0.75 in the control group (p=0.037). One (1/13; 7.6%) patient in the ILM group required additional unplanned surgery versus 8/19 (42.10%) in the control group (p=0.038). Final anatomical success rate defined as attached retina after silicone oil (SiO) removal was 13/13 in the I-ILM group and 14/19 (73.6%) in the control group (p=0.052). No pati...

PurposeOxidative damage to the trabecular meshwork (TM) represents one of the pathogenic mechanis... more PurposeOxidative damage to the trabecular meshwork (TM) represents one of the pathogenic mechanisms leading to primary open angle glaucoma (POAG). Glutathione S-transferase mu 1 (GSTM1) may neutralizes reactive oxygen species protecting the TM. The present paper investigates the prevalence of GSTM1 null genotype in an Italian population, and its association with POAG treated either medically or surgically.MethodsIn a case-control study, the GSTM1 genotype was identified in POAGs and controls. The POAGs patients were divided in two groups: medical POAGs and surgical POAGS. Medical POAGs consisted of patients with a well-controlled intraocular pressure (IOP) by IOP-lowering medications and a stable visual field (VF). Patients with an uncontrolled IOP and a progressing VF that were submitted to incisional surgery formed the surgical POAGs’ group.ResultsWe enrolled 104 medical POAGs, 158 surgical POAGs and 263 Controls. No significative differences between the groups existed regarding a...

European Journal of Ophthalmology, 2019

Background:The purpose of this study is to determine the prevalence of diabetes and diabetic macu... more Background:The purpose of this study is to determine the prevalence of diabetes and diabetic macular edema in patients undergoing senile cataract surgery in Italy.Methods:It is a prospective, multicenter, cross-sectional study. Thirteen ophthalmic units equally distributed across the Italian territory have been involved in the study. For a period of 3 months, all subjects undergoing phacoemulsification received an Optical Coherence Tompgraphy (OCT) scan and were screened for the anamnestic presence of diabetes. In addition, five selected units collected blood samples from all their patients to measure glycated hemoglobin (HbA1c) levels and detect the presence of occult diabetes (HbA1c > 6.5%). In diabetic patients, levels of retinopathy were measured and diabetic macular edema was considered significant (clinically significant macular edema) when foveal thickness was above 30% of normal levels.Results:A total number of 3657 subjects have been screened. Among them, 20.4% were diab...

Experimental Eye Research, 2018

Purpose of present study is to evaluate if the Pre-Macular Bursa (PMB) modifies Wall Shear Stress... more Purpose of present study is to evaluate if the Pre-Macular Bursa (PMB) modifies Wall Shear Stress (WSS) at the retinal surface during saccadic movements. We created a 25,000 cells mathematical in order to calculate WSS throughout the retinal surface. The posterior pole was divided into 3 zones comprising 400 nodes each. Zone 1 (radius 3.5mm; 0°-17°) corresponding to the PMB area; zone 2 (concentric annular area 5 mm in radius; 22°) and zone 3 (concentric annular area 5.5 mm; 28°). The saccade covered 50° in 0.17s. Recording time was 0.34 s. The PMB reduced WSS significantly at the macula and increased it in the immediate surroundings. Average WSS in zone 1 was 1.53 ± 1.01 (max 4.23 Pa) with PMB Vs 6.94 ± 9.23 (max 35.83 Pa) without; in zone 2 was 9.39 ± 10.33 (max 48.36 Pa) with PMB Vs 6.95 ± 9.40 (max 38.60 Pa) without while in zone 3 was 8.41 ± 10.03 (max 43.16 Pa) with PMB Vs 6.88 ± 9.42 (max 39.43 Pa) without. p<0.001 in all cases. The PMB significantly reduces WSS over the retinal surface underlying the bursa region; conversely, WSS slightly increases it in the immediate neighboring areas.

Neurology - Neuroimmunology Neuroinflammation, 2020

In the Clinical/Scientific Note "Acute disseminated encephalomyelitis after SARS-CoV-2 infection"... more In the Clinical/Scientific Note "Acute disseminated encephalomyelitis after SARS-CoV-2 infection" by Novi et al., 1 there is an error in the opening paragraph. The first sentence should read, "Acute disseminated encephalomyelitis (ADEM) is a rare autoimmune disease of the CNS, that often develops after viral infections and mainly affecting children." The publisher regrets the error.

Acta medica Okayama, 2017

Parafoveal retinal holes (PRHs) are one of the complications that can occur after internal limit... more Parafoveal retinal holes (PRHs) are one of the complications that can occur after internal limiting membrane (ILM) peeling during macular surgery. Here we describe a patient in whom an exceptionally large PRH (1,069-μm dia.) was successfully closed by repeated autologous ILM transplantation.

Modeling and Artificial Intelligence in Ophthalmology, 2019

Purpose: Intraocular pressure (IOP) during pars plana vitrectomy (PPV) decreases as aspiration ge... more Purpose: Intraocular pressure (IOP) during pars plana vitrectomy (PPV) decreases as aspiration generates flow, a phenomenon known as head loss. Since direct measurement of the IOP during surgery is impractical, currently, available compensating systems infer IOP by measuring infusion flow rate and estimating corresponding pressure drop. The purpose of the present paper is to propose and validate a physically based algorithm of the infusion pressure drop as a function of flow. Methods: Complete infusion lines (20G, 23G, 25G and 27G) were set up and primed. The infusion bottle was set at incremental heights and flow rate measured 10 times and recorded as mean Å} SD. Overall head loss (OHL) was defined, according to hydraulics laws, as the sum of frictional head loss (FHL; i.e., pressure drop due to friction along tubing) and exit head loss (EHL). The latter is equal to the kinetic energy of the exiting flow through the trocar (FKE = V2/2g). A 2nd degree polynomial equation (i.e., ΔP =...

Investigative Opthalmology & Visual Science, 2011

PURPOSE. To test the hypothesis that blunt trauma shockwave propagation may cause macular and per... more PURPOSE. To test the hypothesis that blunt trauma shockwave propagation may cause macular and peripheral retinal lesions, regardless of the presence of vitreous. The study was prompted by the observation of macular hole after an inadvertent BB shot in a previously vitrectomized eye. METHODS. The computational model was generated from generic eye geometry. Numeric simulations were performed with explicit finite element code. Simple constitutive modeling for soft tissues was used, and model parameters were calibrated on available experimental data by means of a reverse-engineering approach. Pressure, strain, and strain rates were calculated in vitreous-and aqueous-filled eyes. The paired t-test was used for statistical analysis with a 0.05 significance level. RESULTS. Pressure at the retinal surface ranged between Ϫ1 and ϩ1.8 MPa at the macula. Vitreous-filled eyes showed significantly lower pressures at the macula during the compression phase (P Ͻ 0.0001) and at the vitreous base during the rebound phase (P ϭ 0.04). Multiaxial strain reached 20% and 25% at the macula and vitreous base, whereas the strain rate reached 40,000 and 50,000 seconds Ϫ1 , respectively. Both strain and strain rates at the macula, vitreous base, and equator reached lower values in the vitreous-compared with the aqueous-filled eyes (P Ͻ 0.001). Calculated pressures, strain, and strain rate levels were several orders of magnitude higher than the retina tensile strength and load-carrying capability reported in the literature. CONCLUSIONS. Vitreous traction may not be responsible for blunt trauma-associated retinal lesions and can actually damp shockwaves significantly. Negative pressures associated with multiaxial strain and high strain rates can tear and detach the retina. Differential retinal elasticity may explain the higher tendency toward tearing the macula and vitreous base. (Invest

Translational Vision Science & Technology, 2020

To assess whether the use of a patented, novel feedback device intended to accurately control pha... more To assess whether the use of a patented, novel feedback device intended to accurately control phacoemulsification tip elongation is effective under varying machine settings and material resistance. Methods: Sculpt mode phaco (550-mm Hg Venturi pump; elongations, 35 and 70 μm) and quadrant settings (550-mm Hg Venturi pump; elongations, 15, 30, and 60 μm) were used in agar gel of incremental density (1%, 2%, 3%, and 6% in demineralized water). Dispersed lens fragments were also simulated with 6% agar gel spherules (2-5 mm in diameter; 550-mm Hg vacuum, and 60-μm elongation). Actual phaco tip elongation was measured on voltage readings from the piezoelectric crystals and compared to nominal elongation with feedback control off and on. Results: Mismatch between nominal and actual elongation when feedback control was off in sculpt mode varied between-13.51 μm and-23.07 μm of nominal elongation; in quadrant mode, mismatch varied between-2.79 μm and-20.41 μm. When the feedback control system was switched on, mismatch varied between-0.02 μm and +0.43 μm (P < 0.001 for all matchings). When the feedback system was off, the elongation mismatch among the 1%, 3%, and 6% agar was also statistically significant (P < 0.001). Elongation was 44.72 ± 4.16 μm with feedback control off and 60.02 ± 1.63 μm with it on (nominal elongation 60 μm; P < 0.001) when emulsifying agar 6% gel fragments. Dispersion of elongation data was also significantly wider when feedback control was turned off. Conclusions: A novel feedback control system effectively controls elongation accuracy regardless of the resistance offered by incremental agar gel concentrations. Translational Relevance: Implementing feedback control in phaco handpieces dramatically improves surgical accuracy. The translational value of this research relies on its immediate applicability to routine cataract surgery, resulting in a more appropriate use of ultrasound energy.

Graefe's Archive for Clinical and Experimental Ophthalmology

BMJ Open Ophthalmology

ObjectiveTo report the results of a global survey on cataract practice patterns related to preope... more ObjectiveTo report the results of a global survey on cataract practice patterns related to preoperative, intraoperative and postoperative care, surgical setting and personnel allocation.Methods and analysisAn online 28 questions survey was sent to 240 ophthalmologists asking to describe prevailing trends in their institutions across 38 countries and 5 continents. Questions inquired country, institution, surgical volume and setting, anaesthesia, preoperative and intraoperative examination and postsurgical care. Statistical analysis used crosstabs lambda statistics for non-parametric nominal variables. P value less than 0.05 was considered statistically significant.Results209/240 (87%) ophthalmologists responded: 38% representing public hospitals, 36% private practices and 26% academic sites; overall surgical volume was between 241 700 and 410 500 cataracts per year. There was a significant correlation between type of institution and surgical volume. Complete results available in onli...

Journal of Clinical Medicine

Purpose is to review the pathogenic mechanism for ocular hypertension and glaucoma development af... more Purpose is to review the pathogenic mechanism for ocular hypertension and glaucoma development after pars plana vitrectomy. Both acute and chronic causes are considered, and special attention is paid to the theories and clinical evidence on the risk of developing Open Angle Glaucoma (OAG) after Pars Plana Vitrectomy (PPV). Most existing scientific literature on the issue agree on the role of ascorbate as an oxygen scavenger within the vitreous chamber. Oxygen tension in the vitreous and anterior chamber is maximum inn proximity of the retinal surface and endothelium, respectively and steeply decreases toward the lens, on both sides, and trabecular meshwork. Vitreous removal and, to a lesser extent, liquefaction, greatly reduces oxygen tension gradient in vitreous chamber while cataract extraction has similar effects on anterior chamber oxygen gradients. Oxygen derivatives originated from the cornea and retina are actively reduced by the vitreous gel and/or the crystalline lens. Vitr...

Graefe's Archive for Clinical and Experimental Ophthalmology

Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie, Jan 4, 2017

To compare the anatomic and functional outcome of two variants of the inverted internal limiting ... more To compare the anatomic and functional outcome of two variants of the inverted internal limiting membrane (I-ILM) flap technique for idiopathic macular holes (IMH) larger than 400 µm. Twenty-seven consecutive patients undergoing PPV for IMH were randomly assigned to different variants of I-ILM technique: the Cover group included 14 patients in which the I-ILM was folded upside-down over the MH as a single layer while the Fill group enrolled 13 patients in which the I-ILM was folded within the MH in multiple layers. MH closed in 12/14 Cover and in 13/13 Fill eyes (84.6 vs. 100%, p = 0.14; n.s.). Vision at 1 month was Snellen 0.44 ± 0.17 vs. 0.28 ± 0.21 (p = 0.05) and 0.48 ± 0.20 vs. 0.37 ± 0.25 (n.s.) at 3 months. IS/OS line interruption width was 463 ± 385 vs. 602 ± 210 µm, respectively, at 1 month (n.s.) and 602 ± 210 vs. 563 ± 209 µm at 3 months (n.s.). The Cover group showed outer retina cystic changes more often (p < 0.01). MH over 700 µm closed in 0/2 and in 2/2 cases, respe...

Translational vision science & technology, 2016

To measure the hydraulic resistance (HR) of vitreous cutters equipped with a Regular guillotine B... more To measure the hydraulic resistance (HR) of vitreous cutters equipped with a Regular guillotine Blade (RB) or double edge blade (DEB) at cut rates comprised between 0 and 12,000 cuts per minute (CPM) and compare it with vitreous fragment size. This was an in vitro experimental study; in vivo HR measure and vitreous sampling. HR, defined as aspiration pressure/flow rate, was measured in balanced salt solution (BSS; Alcon, Fort Worth, TX) (in vitro) and during pars plana vitrectomy of 20 consecutive patients aged 18 to 65, undergoing macular surgery. HR was recorded at increasing cut rates (500-6000 CPM for the RB and 500-12,000 CPM for the DEB; 5 mL/min flow). Vitreous samples were withdrawn and analyzed with Western and collagen type II and IX immunostaining to evaluate protein size. The main outcome measures were hydraulic resistance (mm Hg/ml/min [±SD]) and optic density for Western blot and immunostaining. RB and DEB showed identical HR in BSS between 0 and 3000 CPM. Above 3000 C...

Retinal Cases Brief Reports, 2007

Wolters Kluwer Health may email you for journal alerts and information, but is committed to maint... more Wolters Kluwer Health may email you for journal alerts and information, but is committed to maintaining your privacy and will not share your personal information without your express consent. For more information, please refer to our Privacy Policy. ... Skip Navigation Links Home &gt; Spring ...

Retina J Retin Vitr Dis, 1997

The purpose of this study was to estimate if and to what extent scanning laser ophthalmoscopy can... more The purpose of this study was to estimate if and to what extent scanning laser ophthalmoscopy can help in the early diagnosis and follow-up management of the vitreoretinal interface syndrome, which includes disorders such as cellophane maculopathy, pseudomacular hole, macular pucker, and macular hole. The 35 fellow eyes of 35 patients with vitreoretinal interface syndromes in the first eye underwent scanning laser ophthalmoscopy microperimetry and argon, helium-neon, and infrared scanning laser ophthalmoscopy. Fellow eyes were defined as clinically positive or negative for vitreoretinal interface syndrome. Fellow eyes then were classified based on scanning laser ophthalmoscopy techniques. Patients were observed for an average of 18 months (range, 10-26 months). Thirty-two of the 35 fellow eyes were classified as clinically negative, and three of the 35 were classified as clinically positive. Fifteen of the 32 clinically negative fellow eyes were redefined as positive on scanning laser ophthalmoscopy. None of the clinically positive eyes proved to be negative on scanning laser ophthalmoscopy. During the average follow-up period (18 months), the condition of five of 18 fellow eyes that were positive on scanning laser ophthalmoscopy worsened. None of the 17 eyes that were negative on scanning laser ophthalmoscopy worsened. Scanning laser ophthalmoscopy can produce beautifully clear images of structures that are otherwise difficult to see and document, such as posterior hyaloid and the inner retinal layers. Despite a relatively limited number of cases and the short duration of the follow-up period, the present study suggests that scanning laser ophthalmoscopy has good sensitivity and specificity for the early diagnosis of vitreoretinal interface syndromes.

Retina, 2015

To characterize the fluidics of axial rotating vitreous cutter probe (RT) compared with the stand... more To characterize the fluidics of axial rotating vitreous cutter probe (RT) compared with the standard guillotine (regular blade), when tested in Balanced Salt Solution (Alcon Laboratories, Forth Worth, TX). RT and regular blade (RB) cutter probes connected to the same vitrectomy console used a peristaltic pump. The authors measured instantaneous flow through aspiration tubing proximal to the handpiece, fluid velocity, and acceleration at the port by means of particle image velocimetry. Average flow at aspiration tubing of RT and RB did not vary significantly. Regular blade probes produced higher instantaneous flow fluctuation than RT at any considered cut rate (RB 1,600 6.4 ± 5.3 mL/minute; RB 3,000 11.8 ± 6.3 mL/minute; RT 1,600 0.9 ± 0.7 mL/minute, and RT 3,000 1.8 ± 0.8 mL/minute, respectively. P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001 in all cases). Regular blade also yield significantly higher fluid velocity at cutter port compared with RT (RB 1,600 85.8 ± 70.1 mm/second; RB 3,000 81.6 ± 66.4 mm/second; RT 1,600 71.9 ± 40.3 mm/second; and RT 3,000 32.9 ± 20.8 mm/second. P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001 in all cases). Fluid acceleration at the cutter port was higher when the RB was used (RB 1,600 26.85 ± 30.18 mm/second; RB 3,000 33.76 ± 34.09 mm/second; RT 1,600 24.01 ± 21.94 mm/second; and RT 3,000 16.62 ± 17.87 mm/second. P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001 in all cases). RT blade design causes less instantaneous flow fluctuation within the aspiration tubing, and also lower fluid velocity and lower acceleration at the cutter port. Fluidics suggests a safer cutting action and a reduced risk of retinal incarceration.