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Rossi T, Querzoli G, Cosimi P, Ripandelli G, Steel DH, Romano MR. TANGENTIAL RETINAL DISPLACEMENT INCREASES AFTER MACULAR PUCKER SURGERY: An Apparent Nonsense. Retina 2024; 44:610-617. [PMID: 37973044 DOI: 10.1097/iae.0000000000004001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
PURPOSE To measure the tangential retinal displacement and vision before and after macular pucker surgery and study if pars plana vitrectomy with epiretinal membrane peeling allows the reconstitution of previous anatomy or else it results in a different configuration. METHODS Retrospective series of patients undergoing pars plana vitrectomy for epiretinal membrane, with >6-month follow-up before and after surgery, complete with best-corrected visual acuity, optical coherence tomography, M-Charts, and infrared retinography. Tangential retinal displacement between earliest visit (T E ), time of surgery (T 0 ), and latest available visit (T L ) of the examined retina, concentric circles at 0.5, 1.5, and 4.5 mm radii, and the central horizontal and vertical meridians were measured. Tangential displacement was calculated as the optical flow of consecutive infrared photographs. RESULTS The study comprised 32 patients: 15 men and 17 women. Average preoperative and postoperative follow-up were 23.4 ± 27.9 months and 19.2 ± 11.8 months, respectively. Best-corrected visual acuity reduced before surgery (0.69 ± 0.16 Snellen to 0.46 ± 0.17; P < 0.001) and increased after (0.866 ± 0.16 Snellen; P < 0.001). Horizontal and vertical metamorphopsia increased between before surgery but only horizontal metamorphopsia significantly reduced after. Average tangential displacement before surgery was 35.6 ± 29.9 µ m versus 56.6 ± 41.3 µ m after ( P = 0.023). Preoperative and postoperative displacement within the fovea was less than over the entire area ( P < 0.001). CONCLUSION Retinal tangential displacement between diagnosis and surgery (T E - T 0 ) is less than the displacement occurring after surgery (T 0 - T L ). Postoperative displacement does not represent the restoration of the anatomy existing before the disease ensued but rather the resulting equilibrium of newly deployed forces.
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Affiliation(s)
| | - Giorgio Querzoli
- DICAAR Faculty of Engineering, University of Cagliari, Cagliari, Italy
| | | | | | - David H Steel
- Newcastle University, Newcastle, United Kingdom; and
| | - Mario R Romano
- Department of Biomedical Science, Humanitas University, Milan, Italy
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Scarinci F, Querzoli G, Cosimi P, Ripandelli G, Romano MR, Cacciamani A, Munk MR, Rossi T. RETINAL TECTONICS AFTER MACULAR PUCKER SURGERY: Thickness Changes and En Face Displacement Recovery. Retina 2024; 44:102-110. [PMID: 37695945 DOI: 10.1097/iae.0000000000003928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
PURPOSE To study visual function, retinal layer thickness changes, and tangential displacement after pars plana vitrectomy for epiretinal membrane. METHODS Retrospective series of patients undergoing pars plana vitrectomy for epiretinal membrane, with 6-month follow-up including best-corrected visual acuity, optical coherence tomography, M-charts, epiretinal membrane grading, and infrared fundus photograph at time 0 (T0, preop) at months 1 (T1), 3 (T3), and 6 (T6) postop (±1 week). Retinal layer thickness and tangential ( en face ) retinal displacement between successive times for the entire retinal surface and the central horizontal and vertical meridian were also measured. En face displacement was calculated as optical flow of consecutive images. RESULTS Average best-corrected visual acuity improved from 0.28 ± 0.08 logarithm of Minimum Angle of Resolution at T0 to 0.16 ± 0.25 at T6 ( P = 0.05), best-corrected visual acuity improvement correlated with best corrected visual acuity (BCVA) at T0 ( P < 0.001). Vertical metamorphopsia decreased from 1.33° ± 0.70° at T0 to 0.82° ± 0.69° at T6 ( P < 0.05). Foveal thickness reduced from 453 ± 53 µ m at T0 to 359 ± 31 µ m at T6 ( P < 0.05) and reduction correlated with best-corrected visual acuity improvement ( P < 0.05). Foveal layers decreased ( P < 0.05) in all cases. The mean en face deformation was 155.82 ± 50.17 µ m and mostly occurred in the first month: T0-T1 displacement was 83.59 ± 30.28 µ m, T1-T3 was 36.28 ± 14.45 µ m, while T3-T6 was 39.11 ± 22.79 µ m ( P < 0.001) on average. Perifoveal and parafoveal deformation correlated with optical coherence tomography foveal thickness reduction at all time intervals (1, 3, and 6 months: P < 0.01). CONCLUSION Epiretinal membrane peeling affects all retinal layer thickness and results in new force balance across the entire retina and tangential displacement. Both en face and in-depth changes correlate with visual function.
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Affiliation(s)
| | | | | | | | - Mario R Romano
- Department of Biomedical Science, Humanitas University, Milan, Italy
| | | | - Marion R Munk
- Augenarzt-Praxisgemeinschaft Gutblick AG, Pfäffikon. Switzerland
- Feinberg School of Medicine, Northwestern University, Chicago, Illinois; and
- Department of Ophthalmology, Inselspital, University Hospital Bern, Bern, Switzerland
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Ledda PG, Rossi T, Badas MG, Querzoli G. Can wall shear-stress topology predict proliferative vitreoretinopathy localization following pars plana vitrectomy? J Biomech 2024; 162:111914. [PMID: 38157782 DOI: 10.1016/j.jbiomech.2023.111914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 12/08/2023] [Accepted: 12/20/2023] [Indexed: 01/03/2024]
Abstract
We numerically study the fluid dynamics of oil tamponade in models of vitrectomized eyes prompted by a subset of daily activities corresponding to movements on the horizontal plane with the patient in a standing position. Bulk flow features are related to near-wall flow topology and transport at the retinal surface through a wall shear-stress-based analysis. Proliferative VitreoRetinopathy (PVR) is the leading cause of retinal re-detachment occurring in about 20% of all cases due to the accumulation of inflammatory cells in discrete retinal regions. Signalling soluble mediators stimulate inflammatory cells' chemotaxis and studying their distribution across the retinal surface may acquire clinical relevance. In all the investigated cases, persistent and elongated regions along the retina, potentially prone to accumulate chemo-attractants and cells are observed. Gradients of soluble inflammation mediators present in the aqueous are known responsible for the so-called epithelial-mesenchymal transition that initiates PVR and favours recurrent retinal detachment prompting the proliferation of inflammatory cells with collagen matrix deposition and its contraction. The surgical apposition of encircling scleral buckling elements, known for over a century to influence PVR formation and localization, modifies the attracting regions, possibly causing an accumulation of molecules and cells along approximately vertical lines that follow the rising menisci due to the cerclage indentation. The resulting spatial pattern is compatible with clinical observations. This study may open toward rational analyses of near-wall transport to predict PVR pathogenesis by relating biochemical accumulation in certain areas of the retina to clinical conditions.
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Affiliation(s)
- P G Ledda
- DICAAR, Università degli Studi di Cagliari, Cagliari, Italy
| | - T Rossi
- IRCCS Fondazione G.B. Bietti ONLUS, Rome, Italy
| | - M G Badas
- DICAAR, Università degli Studi di Cagliari, Cagliari, Italy
| | - G Querzoli
- DICAAR, Università degli Studi di Cagliari, Cagliari, Italy.
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Rossi T, Badas MG, Angius F, Querzoli G. DO DAILY ACTIVITIES AFFECT GAS TAMPONADE‒RETINA CONTACT AFTER PARS PLANA VITRECTOMY?: A Computational Fluid Dynamics Study. Retina 2023; 43:955-963. [PMID: 36800522 PMCID: PMC10187623 DOI: 10.1097/iae.0000000000003750] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
PURPOSE To calculate the retinal surface alternatively in contact with gas and aqueous because of fluid sloshing during daily activities such as ocular saccade, turning the head, standing up, and being a passenger of a braking car. METHODS Fluid dynamics of aqueous and gas tamponade was reproduced using computational methods using the OpenFOAM open-source library. The double-fluid dynamics was simulated by the volume of fluid method and setting the contact angle at the aqueous-gas-retina interface. RESULTS Sloshing increased the retinal surface in contact with aqueous by 13% to 16% regardless of fill rate and standing up determined the largest area of wet retina, followed by car braking, head rotation, and ocular saccade ( P < 0.001). All activities except the ocular saccade determined a significant increase in the surface of retina in contact with the aqueous ( P < 0.005). Car braking induced the highest shear stress (6.06 Pa); standing up determined the highest specific impulse and saccade the lowest. CONCLUSION Daily activities instantaneously reduce the amount of retina consistently in contact with gas tamponade and increase shear stress giving aqueous a potential access to the subretinal space regardless of patients' compliance.
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Affiliation(s)
- Tommaso Rossi
- IRCCS Fondazione G.B. Bietti ONLUS, Roma, Italy; and
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Rossi T, Canepa P, Cavalleri O, Rolandi R, Querzoli G, D'Agostino I, Telani S, Ripandelli G. Silicone Oil Tamponade Removal: Which Technique Is More Effective? An X-Ray Photoemission Spectroscopy Study. Transl Vis Sci Technol 2023; 12:21. [PMID: 37070937 PMCID: PMC10123323 DOI: 10.1167/tvst.12.4.21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2023] Open
Abstract
Purpose To compare the efficacy of two surgical techniques used to remove silicone oil (SiO) emulsion tamponade after pars plana vitrectomy: triple air-fluid exchange (AFX) and balanced salt solution lavage (BSSL). Methods X-ray photoemission spectroscopy measured silicon content of the dry residue of fluid samples taken during AFX and BSSL. Ten patients underwent AFX and five BSSL. Three fluid samples were taken per patient, and the dry residue of 10 drops per sample were analyzed. A fluid sample from a patient who never received SiO tamponade was also analyzed to set a "blank" reference sample. Results Patients' demographics showed no significant difference. Sample 1 of the two groups contained comparable silicon content while samples 2 and 3 of the AFX group contained significantly more silicon than that of the BSSL group (15.0 ± 0.1 and 12.0 ± 0.9 for the AFX group vs. 10.7 ± 1.4 and 5.2 ± 0.6 for the BSSL group, respectively; P < 0.05). The cumulative amount of silicon in the three successive samples was also significantly higher for the AFX group (42.3 ± 1.6 vs. 32 ± 2; P < 0.0001). The average silicon content ratio of consecutive samples was significantly higher for the AFX group compared to the BSSL group (0.90 ± 0.01 vs. 0.58 ± 0.06; P = 0.006). Conclusions Triple AFX removed more silicon than triple lavage. The eye wall actively interacts with silicon emulsion retaining silicon content rather than behaving as a neutral container. Translational Relevance Triple air-fluid exchange removed more silicon than BSS lavage. Neither technique behaved as a well-mixed box dilution, suggesting the eye walls actively retain emulsion and a dynamic equilibrium is established between silicon dispersion and the eye wall surface.
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Affiliation(s)
| | - Paolo Canepa
- Department of Physics, University of Genoa, Genoa, Italy
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Rossi T, Romano MR, Carotenuto A, Malvasi C, Angelini GB, Rossi A, Telani S, Ripandelli G, Querzoli G. Phacoemulsification Tip Elongation Under Standardized Resistance: An Objective Measure of Human Crystalline Lens Hardness. Transl Vis Sci Technol 2023; 12:6. [PMID: 37017957 PMCID: PMC10082381 DOI: 10.1167/tvst.12.4.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2023] Open
Abstract
Purpose To establish a correlation between phacoemulsification tip normalized driving voltage (NDV) and crystalline lens hardness and use it as an objective measure of lens hardness. The study used a phaco tip equipped with previously validated elongation control adjusting the driving voltage (DV) to produce invariant elongation regardless of resistance. Methods The laboratory study measured the mean and maximum DV of the phaco tip immersed in glycerol-balanced salt solution and correlated the DV with the kinematic viscosity at 25, 50, and 75 µm tip elongation. The NDV were obtained by dividing the DV in glycerol by the DV in the balanced salt solution. The clinical arm of the study recorded DV of 20 consecutive cataract surgeries. The correlation of mean and maximum NDV to Lens Opacities Classification System (LOCS) III classification, patient's age and effective phaco time were evaluated. Results The mean and maximum NDV correlated with the kinematic viscosity of the glycerol solution (P < 0.001 in all cases). Mean and maximum NDV during cataract surgery correlated with patients' age, effective phaco time, LOCS III nuclear color, and nuclear opalescence (P < 0.001 in all cases). Conclusions When a feedback algorithm is running, DV variation strictly correlates with encountered resistance in glycerol solutions and real-life surgery. NDV significantly correlates with the LOCS classification. Future developments might include sensing tips that react to lens hardness in real time. Translational Relevance The study correlates for the first time phaco tip DV and crystalline lens mechanical properties, establishing an objective and reliable measure of lens hardness. This may lead to smart phaco tips reacting to cataract hardness change in real time and sparing ultrasound dispersion.
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Affiliation(s)
| | - Mario R Romano
- Department of Biomedical Science, Humanitas University, Milan, Italy
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Rossi T, Querzoli G, Badas MG, Angius F, Ripandelli G. Silicone Oil Tamponade-Retina Contact in Highly Myopic Eyes With and Without Encircling Bands: A Computational Fluid Dynamics Study. Transl Vis Sci Technol 2022; 11:1. [PMID: 35648638 PMCID: PMC9172018 DOI: 10.1167/tvst.11.6.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Purpose To investigate the behavior of silicone oil (SiO) at a steady equilibrium and during saccades in pseudophakic highly myopic eyes with posterior staphyloma with and without an encircling band and compare it to behavior in emmetropic eyes. The SiO–retina contact area and shear stress were calculated by computational fluid dynamics. Methods A numerical model of an emmetropic eye and a myopic eye with and without scleral band underwent a saccade of 50°/0.137 s. The vitreous chamber surface was divided into superior and inferior 180° sectors: lens, pre-equator, post-equator, and macula. SiO–retina contact was evaluated as a function of fill percentages between 80% and 90% for standing, 45° upward tilt, and supine patients. Maximum and average shear stress were calculated. Results Overall, SiO–retina contact ranged between 40% and 83%; fill percentage varied between 80% and 95%. Neither the encircling scleral band nor the staphyloma significantly affected the SiO–retina contact area, although the presence of a scleral band proved disadvantageous when gazing 45° upward. The inferior retina–SiO contact remained below 40% despite 95% SiO fill. The SS significantly increased at the scleral band indentation and decreased elsewhere. The staphyloma greatly reduced shear stress at the macula. Conclusions The presence of a myopic staphyloma reduces shear stress at the macula but does not alter SiO–retina contact significantly. The apposition of a 360° scleral band may reduce SiO–retina contact at least in some postures and increases the SS at the indentation. Translational Relevance Assessing SiO–retina contact when vitreous chamber geometry changes according to pathologic or iatrogenic modifications allows accurate prediction of real-life tamponade behavior and helps explain surgical outcomes.
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Affiliation(s)
- Tommaso Rossi
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | | | | | | | - Guido Ripandelli
- IRCCS Fondazione G.B. Bietti per lo Studio e la Ricerca in Oftalmologia ONLUS, Rome, Italy
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Rossi T, Speciale A, Menichini P, Izzotti A, D'Agostino I, Trillo C, Telani S, Querzoli G, Ripandelli G. Human Vitreous Collagen Fragments Dimension As a Function of Vitrectomy Cut Rate. Transl Vis Sci Technol 2022; 11:29. [PMID: 35333285 PMCID: PMC8963665 DOI: 10.1167/tvst.11.3.29] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Purpose To study the dimensions and distribution of human vitreous collagen type II fragments collected after vitrectomy performed at varying cut rates and to evaluate if increasing the cut rate produces smaller collagen fragments, thus reducing retinal traction and/or viscosity. Methods Fluid was collected during core vitrectomies performed for macular surgery at cut rates from 1000 to 16,000 cuts per minute (CPM) and immediately refrigerated. Protein fractions were separated by molecular weight (MW; >100 kDa, 50–100 kDa, 50–30 kDa, 30–10 kDa, and <10 kDa) through centrifugal filters. The Human Collagen II ELISA Kit colorimetric assay was then used to measure the COL2A1 in unfiltered and filtered samples. Results Vitreous samples collected after vitrectomy performed at 16,000 CPM contained a higher concentration of protein with MW over 100 kDa than at any other cutting frequency (P < 0.01). No significant differences were found in fractions collected with a MW between 50 and 100 kDa. Collagen type II fragments over 100 kDa were significantly more represented than smaller fragments at each cut rate. The proportion of smaller (50–100 kDa) collagen fragments compared with those over 100 kDa was higher at 2000 CPM than at higher cut rates. Conclusions Vitreous samples collected at different cut rates do not contain a significantly different proportion of collagen type II fragments of the tested MW. The extreme variability of vitreous flow through the cutter port may explain the uncertain predictability of collagen fragment MWs. Translational Relevance Increasing the cut rate does not produce vitreous fragments of proportionally smaller dimension. It is necessary to achieve an invariant instantaneous flow through the cutter port in order to decrease retinal traction during vitrectomy.
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Affiliation(s)
- Tommaso Rossi
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Andrea Speciale
- Mutagenesis and Cancer Prevention Unit, Comprehensive Cancer Center, IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Paola Menichini
- Mutagenesis and Cancer Prevention Unit, Comprehensive Cancer Center, IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Alberto Izzotti
- Mutagenesis and Cancer Prevention Unit, Comprehensive Cancer Center, IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | | | | | - Serena Telani
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
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Abstract
Purpose To investigate the behavior of silicone oil (SiO) at the steady equilibrium and during saccades and calculate SiO-retina contact, shear stress (SS), and shear rate (SR). Methods A 24 mm phakic eye mesh model underwent 50°/0.137s saccade. The vitreous chamber compartment was divided into superior and inferior 180° sectors: lens, pre-equator, postequator, and macula. SiO-retina contact was evaluated as a function of fill percentages between 80% and 90% for a standing patient, 45° upward gaze, and supine. SS and SR for 1000 mPa-s (SiO1000) and 5000 mPa-s (SiO5000) silicon oil were calculated. Results SiO fill between 80% to 90% allowed 55% to 78% retinal contact. The superior retina always kept better contact with SiO, regardless of the fill percentage (P < 0.01). SiO interface thoroughly contacted the macula only in standing position. SS followed a bimodal behavior and was always significantly higher for SiO5000 compared to SiO1000 (P < 0.01) throughout the saccade. The macula suffered the highest mean SS in standing position, while throughout the saccade the average SS was maximum at the SiO-aqueous interface. SR was significantly higher for SiO1000 compared to SiO5000 (P < 0.001). Conclusions SS on the retinal surface may instantaneously exceed reported retinal adhesiveness values especially at the SiO-aqueous interface and possibly favor redetachment. Despite 90% SiO fill the inferior retina remains extremely difficult to tamponade. Translational Relevance Accurate assessment of retina-tamponade interaction may explain recurrent inferior retinal redetachment, silicone oil emulsification, and help to develop better vitreous substitutes.
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Bertoglio P, Ventura L, Aprile V, Cattoni M, Nachira D, Lococo F, Rodriguez M, Guerrera F, Minervini F, Gnetti L, Bacchin D, Franzi F, Querzoli G, Rindi G, Bellafiore S, Femia F, Viti A, Kestenholz P, Ruffini E, Paci M, Margaritora S, Imperatori A, Lucchi M, Ampollini L, Terzi A. P08.01 Prognostic Impact of Second Predominant Pattern in Lung Adenocarcinoma: Analysis From a Large Multicentric European Database. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.01.420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Rossi T, Saffioti S, Angelini G, Querzoli G, Telani S, Rossi A, Ripandelli G. Testing a Novel Device for Accurate Ultrasound Delivery During Crystalline Lens Phacoemulsification Surgery. Transl Vis Sci Technol 2020; 9:7. [PMID: 32704427 PMCID: PMC7347506 DOI: 10.1167/tvst.9.3.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose 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.
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Affiliation(s)
- Tommaso Rossi
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | | | | | - Giorgio Querzoli
- Department of Civil, Environmental, and Architectural Engineering, Università di Cagliari, Cagliari, Italy
| | - Serena Telani
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
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Bertoglio P, Cattoni M, Nachira D, Lococo F, Aprile V, Rodriguez M, Guerrera F, Franzi F, Viti A, Bellafiore S, Rindi G, Bacchin D, Lozano Escario M, Femia F, Querzoli G, Tobar LG, Ruffini E, Paci M, Margaritora S, Lucchi M, Imperatori A, Terzi A. P2.17-29 Impact of Second Predominant Pattern on Recurrence in Early Stage Resected Lung Adenocarcinoma: A Multicentric Study. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.1940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ferrari S, Badas MG, Garau M, Salvadori L, Seoni A, Querzoli G. On The Effect Of The Shape Of Buildings And Chimneystacks On Ventilation And Pollutant Dispersion. EPJ Web Conf 2019. [DOI: 10.1051/epjconf/201921302017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The purpose of this work is to investigate the modifications induced by the change of the roof shape in the flow field, inside and above the buildings, with an attention to their capability to modify the air quality and the dispersion of pollutants released from chimneystacks. We have carried out laboratory experiments on arrays of identical buildings, with symmetrical dual-pitched or flat roofs, and chimneystacks of different heights and positions. The experiments have been carried out in a close-loop water-channel, where two non-intrusive and quasi-continuous in space Digital Image Analysis technique have been implied to measure the velocity fields (Feature Tracking Velocimetry) and the concentration fields (Laser Induced Visualization). Results have highlight the meaningful role of gabled roofs in modifying turbulence, which increases the air exchange rate between the street canyon and the outer flow, but, in some conditions, they increase the dragging of pollutant inside the canyon. These results can have an immediate practical impact on the building design and on planning strategies, as the roof shape can be a useful tool to enhance natural ventilation and pollutant, humidity and/or heat dispersion, i.e. the air quality in urban and industrial areas.
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Rossi T, Badas MG, Querzoli G, Trillo C, Telani S, Landi L, Gattegna R, Ripandelli G. Does the Bursa Pre-Macularis protect the fovea from shear stress? A possible mechanical role. Exp Eye Res 2018; 175:159-165. [PMID: 29935948 DOI: 10.1016/j.exer.2018.06.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/24/2018] [Accepted: 06/19/2018] [Indexed: 10/28/2022]
Abstract
Purpose of present study is to evaluate whether the Pre-Macular Bursa (PMB) modifies Wall Shear Stress (WSS) at the retinal surface during saccadic movements. We created a mathematical model consisting of 25,000 grid cells and simulated a horizontal saccade spanning 50° in 0.17s, both in absence and in presence of the PMB. Wall Shear Stress SS was computed throughout the retinal surface and the posterior pole was divided into 3 Zones comprising 400 nodes each: Zone 1 (radius 3.5 mm; 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 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. Zone 2 WSS was 9.39 ± 10.33 (max 48.36 Pa) with PMB Vs 6.95 ± 9.40 (max 38.60 Pa) without Zone 3 WSS 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.
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Affiliation(s)
- Tommaso Rossi
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy.
| | | | | | | | - Serena Telani
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Laura Landi
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
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Abstract
Negatively buoyant jets develop when fluids are released upwards into a lighter fluid or, vice versa, downwards into a heavier fluid. There are many engineering applications, such as the discharge, via submerged outfalls, of brine from desalination plants into the sea. Some concerns are raised about the potential negative environmental impacts of this discharge. The increase in salinity is the major cause for environmental impact, as it is very harmful to many marine species. The diffusers for brine discharge are typically inclined upwards, to increase the path before the brine reaches the sea bottom, as it tends to fall downwards driven by negative buoyancy. The negatively buoyant jet that develops conserves axisymmetry only when released vertically, so that it is not possible to use the well-known equations for axisymmetric jets. The main target of this paper is to investigate on a laboratory model the effects of different stratifications on the features of negatively buoyant jets. This has been done via a LIF (Light Induced Fluorescence) technique, testing various release angles on the horizontal and densimetric Froude numbers. Except for the initial stage, a different widening rate for the upper boundary and the lower boundary has been highlighted.
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Rossi T, Querzoli G, Gelso A, Angelini G, Rossi A, Corazza P, Landi L, Telani S, Ripandelli G. Ocular perfusion pressure control during pars plana vitrectomy: testing a novel device. Graefes Arch Clin Exp Ophthalmol 2017; 255:2325-2330. [PMID: 28887584 DOI: 10.1007/s00417-017-3799-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Revised: 08/17/2017] [Accepted: 08/31/2017] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To study the efficacy of a novel device intended to control infusion pressure based on mean ocular perfusion pressure (MOPP) during pars plana vitrectomy (PPV). METHODS An arm blood pressure cuff connected to a vitrectomy machine calculated mean arterial pressure (MAP), while a pressure sensor close to the infusion trocar measured intraocular pressure (IOP). MOPP was calculated in real time in 36 consecutive patients undergoing PPV, who were divided into two groups. The device lowered IOP every time that calculated MOPP fell below 30 mmHg in the Control ON group (18 patients), while no action was taken in the Control OFF group (18 patients). RESULTS Baseline IOP and blood pressure were similar between groups. The Control ON group had significantly lower average intraoperative IOP (30.5 ± 2.1 vs. 35.9 ± 6.9 mmHg; p = 0.002) and higher MOPP (56.4 ± 5.9 vs. 49.7 ± 6.1 mmHg) than the Control OFF group. The Control ON group also spent less time at MOPP < 10 mmHg and < 30 mmHg: 0 vs. 3.40 ± 2.38 min (p < 0.001) and 9.91 ± 7.15 vs. 16.13 ± 8.12 min (p = 0.02), respectively. CONCLUSIONS The MOPP control device effectively maintained lower IOP and higher MOPP throughout surgery. It also helped avoid dangerous IOP peaks and MOPP dips, allowing patients to spend less time at MOPP of < 10 and < 30 mmHg.
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Affiliation(s)
- Tommaso Rossi
- San Martino Hospital, Largo Rosanna Benzi 2, 16100, Genoa, Italy.
| | | | - Aldo Gelso
- UO oculistica Clinica Villa dei Fiori, Acerra - Napoli, Acerra, Italy
| | | | | | - Paolo Corazza
- San Martino Hospital, Largo Rosanna Benzi 2, 16100, Genoa, Italy
| | - Laura Landi
- San Martino Hospital, Largo Rosanna Benzi 2, 16100, Genoa, Italy
| | - Serena Telani
- San Martino Hospital, Largo Rosanna Benzi 2, 16100, Genoa, Italy
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Rossi T, Querzoli G, Angelini G, Malvasi C, Rossi A, Morini M, Iossa M, Ripandelli G. AXIAL ROTATION VITRECTOMY: Back to the Future? the Fluidics of a Prototype Vitreous Cutter Probe. Retina 2017; 36:1252-9. [PMID: 26655617 DOI: 10.1097/iae.0000000000000896] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE 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). METHODS 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. RESULTS 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 < 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 < 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 < 0.001 in all cases). CONCLUSION 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.
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Affiliation(s)
- Tommaso Rossi
- *Department of Neurosciences, Azienda Ospedaliera Universitaria San Martino IRCCS, Genoa, Italy; †University of Cagliari, DICAAT, Cagliari, Italy; ‡Optikon 2000 Inc., Rome, Italy; and §Fondazione G.B. Bietti IRCCS, Rome, Italy
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Susin FM, Espa S, Toninato R, Fortini S, Querzoli G. Integrated strategy for in vitro characterization of a bileaflet mechanical aortic valve. Biomed Eng Online 2017; 16:29. [PMID: 28209171 PMCID: PMC5314609 DOI: 10.1186/s12938-017-0314-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Accepted: 01/17/2017] [Indexed: 12/31/2022] Open
Abstract
Background
Haemodynamic performance of heart valve prosthesis can be defined as its ability to fully open and completely close during the cardiac cycle, neither overloading heart work nor damaging blood particles when passing through the valve. In this perspective, global and local flow parameters, valve dynamics and blood damage safety of the prosthesis, as well as their mutual interactions, have all to be accounted for when assessing the device functionality. Even though all these issues have been and continue to be widely investigated, they are not usually studied through an integrated approach yet, i.e. by analyzing them simultaneously and highlighting their connections. Results
An in vitro test campaign of flow through a bileaflet mechanical heart valve (Sorin Slimline 25 mm) was performed in a suitably arranged pulsatile mock loop able to reproduce human systemic pressure and flow curves. The valve was placed in an elastic, transparent, and anatomically accurate model of healthy aorta, and tested under several pulsatile flow conditions. Global and local hydrodynamics measurements and leaflet dynamics were analysed focusing on correlations between flow characteristics and valve motion. The haemolysis index due to the valve was estimated according to a literature power law model and related to hydrodynamic conditions, and a correlation between the spatial distribution of experimental shear stress and pannus/thrombotic deposits on mechanical valves was suggested. As main and general result, this study validates the potential of the integrated strategy for performance assessment of any prosthetic valve thanks to its capability of highlighting the complex interaction between the different physical mechanisms that govern transvalvular haemodynamics. Conclusions We have defined an in vitro procedure for a comprehensive analysis of aortic valve prosthesis performance; the rationale for this study was the belief that a proper and overall characterization of the device should be based on the simultaneous measurement of all different quantities of interest for haemodynamic performance and the analysis of their mutual interactions. Electronic supplementary material The online version of this article (doi:10.1186/s12938-017-0314-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Francesca Maria Susin
- Cardiovascular Fluid Dynamics Laboratory HER, Department of Civil, Environmental and Architectural Engineering, University of Padua, Padua, Italy
| | - Stefania Espa
- Department of Civil and Environmental Engineering, Sapienza University of Rome, Rome, Italy.
| | - Riccardo Toninato
- Cardiovascular Fluid Dynamics Laboratory HER, Department of Civil, Environmental and Architectural Engineering, University of Padua, Padua, Italy
| | - Stefania Fortini
- Department of Civil and Environmental Engineering, Sapienza University of Rome, Rome, Italy
| | - Giorgio Querzoli
- Department of Civil, Environmental Engineering and Architecture, University of Cagliari, Cagliari, Italy
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Rossi T, Querzoli G, Angelini G, Malvasi C, Rossi A, Morini M, Esposito G, Micera A, di Luca NM, Ripandelli G. Hydraulic Resistance of Vitreous Cutters: The Impact of Blade Design and Cut Rate. Transl Vis Sci Technol 2016; 5:1. [PMID: 27441099 PMCID: PMC4942252 DOI: 10.1167/tvst.5.4.1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 03/26/2016] [Indexed: 11/24/2022] Open
Abstract
Purpose 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. Methods 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. Results RB and DEB showed identical HR in BSS between 0 and 3000 CPM. Above 3000 CPM, RB HR steadily increased, and was significantly higher than DEB HR. Vitreous HR was also similar for the two blades between 0 and 1500 CPM. Above 1500 CPM, RB offered a significantly higher resistance. Western blot and immunostaining of vitreous samples did not yield a significant difference in size, regardless of blade type and cut rate. Conclusions DEB is more efficient, offering a lower HR than RB over 1500 CPM in human vitreous. There is no viscosity reduction as a function of cut-rate between 1500 and 12,000 CPM, as HR does not vary. Translational Relevance Future vitreous cutters will benefit of a DEB; optimal cut rate needs to be defined, and the simple increase of cut rate does not provide benefits after a certain limit to be assessed.
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Affiliation(s)
- Tommaso Rossi
- IRCCS Azienda Ospedaliera Universitaria San Martino, IST Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy
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Ferrari S, Badas MG, Querzoli G. A non-intrusive and continuous-in-space technique to investigate the wave transformation and breaking over a breakwater. EPJ Web of Conferences 2016. [DOI: 10.1051/epjconf/201611402022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Ferrari S, Querzoli G. Laboratory experiments on the interaction between inclined negatively buoyant jets and regular waves. EPJ Web of Conferences 2015. [DOI: 10.1051/epjconf/20159202018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Rossi T, Querzoli G, Angelini G, Rossi A, Malvasi C, Iossa M, Ripandelli G. Ocular Perfusion Pressure During Pars Plana Vitrectomy: A Pilot Study. Invest Ophthalmol Vis Sci 2014; 55:8497-505. [DOI: 10.1167/iovs.14-14493] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Rossi T, Querzoli G, Angelini G, Rossi A, Malvasi C, Iossa M, Ripandelli G. Instantaneous flow rate of vitreous cutter probes. Invest Ophthalmol Vis Sci 2014; 55:8289-94. [PMID: 25414180 DOI: 10.1167/iovs.14-15467] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE We report on instantaneous volumetric flow rate of vitreous cutters measured by means of particle image velocimetry (PIV). METHODS In an in vitro experimental study, vitreous cutters mounting a regular blade (RB) or modified Twedge blade (TB) engineered for higher flow were connected to a console machine equipped with a double peristaltic and Venturi pump, and immersed in balanced salt solution (BSS). Instantaneous flow was measured on aspiration tubing sections proximal to the cutter hand piece. Measures settings were as follows: (1) regular functioning at 3000 and 6000 cuts per minute (cpm) with 300 mm Hg aspiration with both pumps, (2) aspiration tubing clamped proximal to pump cassette, and (3) aspiration tubing clamped proximal to hand piece, and (4) flow fluctuation as a function of cut rate also was calculated. For main outcome measures, instantaneous volumetric flow rate in mL/min and flow fluctuation measured as the standard deviation of flow rate were measured. RESULTS Regular functioning shows sinusoidal flow oscillating at cut rate frequency, with amplitude between ±50 mL/min at 3000 cpm and ±35 mL/min at 6000 cpm. The TB always determined a bimodal wave and neither blade nor pump type influenced the sinusoidal pattern of flow. Clamping aspiration tubing zeroes flow, but does not influence fluctuation frequency or amplitude. Clamping at the hand piece determined a significantly higher oscillation. Oscillation amplitude retain a typical resonance pattern with significant changes in function of cut rate and resonance occurs at approximately 4000 cpm. CONCLUSIONS Cutter blade action determines instantaneous flow rate fluctuation that interferes significantly with cutter suction and hampers a steady suction through cutter port. In a surgical scenario, this translates into a higher risk of inadvertent retinal entrapment and lower predictability of cutter behavior, especially at frequency approaching resonance.
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Querzoli G, Fortini S, Espa S, Costantini M, Sorgini F. Fluid dynamics of aortic root dilation in Marfan syndrome. J Biomech 2014; 47:3120-8. [DOI: 10.1016/j.jbiomech.2014.06.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 06/09/2014] [Accepted: 06/18/2014] [Indexed: 12/20/2022]
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Besalduch L, Badas M, Ferrari S, Querzoli G. Experimental Studies for the characterization of the mixing processes in negative buoyant jets. EPJ Web of Conferences 2013. [DOI: 10.1051/epjconf/20134501012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Rossi T, Querzoli G, Pasqualitto G, Iossa M, Placentino L, Repetto R, Stocchino A, Ripandelli G. Ultrasound imaging velocimetry of the human vitreous. Exp Eye Res 2012; 99:98-104. [DOI: 10.1016/j.exer.2012.03.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 03/24/2012] [Accepted: 03/27/2012] [Indexed: 11/30/2022]
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Domenichini F, Querzoli G, Cenedese A, Pedrizzetti G. Combined experimental and numerical analysis of the flow structure into the left ventricle. J Biomech 2006; 40:1988-94. [PMID: 17097665 DOI: 10.1016/j.jbiomech.2006.09.024] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2006] [Accepted: 09/18/2006] [Indexed: 11/30/2022]
Abstract
Fluid dynamics is used for diagnosis in cardiology only to a partial extent. Indeed several aspects of cardiac flows and their relation with pathophysiology are unknown. The flow that develops into the left ventricle is here studied by using a combination of numerical and experimental models. The former allows a detailed three-dimensional analysis, the latter can be used in conditions, like in presence of turbulence, that are out of reach of the current computational power. The three-dimensional flow dynamics is analyzed in terms of its vortical structure. The study, within its limitations, provides further physical understanding about the intraventricular flow structure. This could eventually support the development of cardiac diagnostic indicators based on fluid dynamics.
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Affiliation(s)
- F Domenichini
- Dipartimento di Ingegneria Civile, University of Firenze, Italy.
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Falchi M, Querzoli G, Romano G. Pulsatile flows through orifices. J Biomech 2006. [DOI: 10.1016/s0021-9290(06)84188-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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