M. Ferrari

Università degli Studi di Brescia, Brescia, Lombardy, Italy

Are you M. Ferrari?

Claim your profile

Publications (91)86.84 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Recently, there has been an increasing interest in the role of deep fascia mobility in musculoskeletal dynamics and chronic pain mechanisms; however, no strategies have been presented so far to study in vivo fascial motion in 3D. This paper presents a semiautomatic method, based on ultrasound (US) imaging, enabling a 3D evaluation of fascia mobility. The proposed approach relies on the acquisition of 3D US datasets at rest and during a voluntary muscular contraction and consists of two phases: 3D US dataset analysis and generation of a displacement vector field using a block matching technique (Phase 1) and validation and filtering of the resulting displacement vector field for outliers removal (Phase 2). The accuracy and effectiveness of the proposed method were preliminarily tested on different 3D US datasets, undergoing either simulated (procedural) or real (muscular contraction) deformations. As for the simulated deformation, estimated displacement vectors resulting from Phase 1 presented a mean magnitude percentage error of 8.05 % and a mean angular error of [Formula: see text] which, after Phase 2, were reduced by 69.44 and by 83.05 %, respectively. Tests on real deformations further validated the effectiveness of Phase 2 in the removal of outliers from the displacement vector field. Obtained results preliminarily demonstrate the viability of the proposed algorithm for the analysis of fascia mobility. Such analysis can enable clinicians to better understand the fascia role in musculoskeletal dynamics and disorder. Further experiments are needed to optimize the method in consideration of the anatomical region to be studied.
    International Journal of Computer Assisted Radiology and Surgery 03/2015; DOI:10.1007/s11548-015-1167-4 · 1.36 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Ultrasound (US) imaging offers advantages over other imaging modalities and has become the most widespread modality for many diagnostic and interventional procedures. However, traditional 2D US requires a long training period, especially to learn how to manipulate the probe. A hybrid interactive system based on mixed reality was designed, implemented and tested for hand-eye coordination training in diagnostic and interventional US.
    International Journal of Computer Assisted Radiology and Surgery 09/2014; DOI:10.1007/s11548-014-1113-x · 1.66 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Vessel lumen centerline extraction is an important issue for the intra-operative guidance of endovascular instruments; furthermore, vessel centerline is often used as a reference position in many hemodynamic studies, especially in carotid arteries. In this work we propose an innovative method for the extraction of carotid vessels centerline from three-dimensional Color Doppler ultrasound images. The method was tested on carotid Color Doppler images of eighteen healthy subjects and validated by calculating the Euclidean distances between the centerlines detected by the algorithm and those manually annotated by two experts in the corresponding original US volumes. The results show that the proposed approach can accurately estimate the actual centerline with an average error of 1.08 ± 0.54 mm. Furthermore, the method is completely automatic and therefore suitable for the aforementioned purposes.
    36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society EMBC, Chicago; 08/2014
  • [Show abstract] [Hide abstract]
    ABSTRACT: Magnetic guide of endovascular devices or magnetized therapeutic microparticles to the specific target in the arterial tree is increasingly studied, since it could improve treatment efficacy and reduce side effects. Most proposed systems use external permanent magnets attached to robotic manipulators or magnetic resonance imaging (MRI) systems to guide internal carriers to the region of treatment. We aim to simplify this type of procedures, avoiding or reducing the need of robotic arms and MRI systems in the surgical scenario. On account of this we investigated the use of a wearable stereoscopic video see-through augmented reality system to show the hidden vessel to the surgeon; in this way, the surgeon is able to freely move the external magnet, following the showed path, to lead the endovascular magnetic device towards the desired position. In this preliminary study, we investigated the feasibility of such an approach trying to guide a magnetic capsule inside a vascular mannequin. The high rate of success and the positive evaluation provided by the operators represent a good starting point for further developments of the system.
    36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society EMBC, Chicago; 08/2014
  • Augmented and Virtual Reality, 01/2014: chapter 33: pages 428-433; Springer International Publishing., ISBN: 978-3-319-13968-5
  • Salento AVR, Lecce, Italy; 01/2014
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We present the results of an extensive characterization of physical and electrostatic effects influencing the dynamical behavior of a micro-electromechanical (MEMS) accelerometer based on commercial technology. A similar device has been utilized recently to demonstrate the effect of Casimir and other nano-scale interactions on the pull-in distance [Ardito et. al., Microelectron. Reliab., 52 (2012) 271]. In the present work, we focus on the influence of pressure, plate separation, and electric surface potentials on the spectral mechanical response. We finally find evidence for the presence of non-viscous damping due to compressibility of the ambient gas, and demonstrate a strong dependence of the sensitivity on the parameters of the operating point.
    Procedia Engineering 01/2014; 87:827-830. DOI:10.1016/j.proeng.2014.11.279
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this study we evaluated the diagnostic performance of (99m)Tc-HMPAO-leucocyte ((99m)Tc-HMPAO-WBC) scintigraphy in a consecutive series of 55 patients (46 men and 9 women, mean age 71 ± 9 years, range 50 - 88 years) with a suspected late or a low-grade late vascular prosthesis infection (VPI), also comparing the diagnostic accuracy of WBC with that of other radiological imaging methods. All patients suspected of having VPI underwent clinical examination, blood tests, microbiology, US and CT, and were classified according to the Fitzgerald criteria. A final diagnosis of VPI was established in 47 of the 55 patients, with microbiological confirmation after surgical removal of the prosthesis in 36 of the 47. In the 11 patients with major contraindications to surgery, the final diagnosis was based on microbiology and clinical follow-up of at least 18 months. (99m)Tc-HMPAO-WBC planar, SPECT and SPECT/CT imaging identified VPI in 43 of 47 patients (20 of these also showed infection at extra-prosthetic sites). In the remaining eight patients without VPI, different sites of infections were found. The use of SPECT/CT images led to a significant reduction in the number of false-positive findings in 37 % of patients (sensitivity and specificity 100 %, versus 85.1 % and 62.5 % for stand-alone SPECT). Sensitivity and specificity were 34 % and 75 % for US, 48.9 % and 83.3 % for CT, and 68.1 % and 62.5 % for the FitzGerald classification. Perioperative mortality was 5.5 %, mid-term mortality 12 %, and long-term mortality 27 %. Survival rates were similar in patients treated with surgery and antimicrobial therapy compared to patients treated with antimicrobial therapy alone (61 % versus 63 %, respectively), while infection eradication at 12 months was significantly higher following surgery (83.3 % versus 45.5 %). (99m)Tc-HMPAO-WBC SPECT/CT is useful for detecting, localizing and defining the extent of graft infection in patients with late and low-grade late VPI with inconclusive radiological findings. (99m)Tc-HMPAO-WBC SPECT/CT might be used to optimize patient management.
    European Journal of Nuclear Medicine 10/2013; 41(2). DOI:10.1007/s00259-013-2582-9 · 4.53 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The purpose of this in vitro study was to clinically assess the feasibility of a three-dimensional (3D) electromagnetic (EM) navigator, including sensorized catheters and guidewires, to determine any reduction in radiation dose and contrast medium injection. The study was performed using a navigator prototype developed at the EndoCAS center. The system includes catheters and guidewires simultaneously tracked with an EM localizer (Aurora, Northern Digital, Waterloo, Canada). Tests were performed on a commercial abdominal aortic aneurysm model. Fifteen operators were asked to cannulate renal arteries using the conventional fluoroscopic guidance and the EM navigator without fluoroscopic support. Each trial was video-recorded and analyzed for timing and success of completing the cannulation task by two blinded and independent observers. Performances were also qualitatively evaluated using the Imperial College Endovascular Cannulation Scoring Tool (IC3ST). Moreover, a questionnaire was administered to participants to evaluate the navigator potentialities. Quantitative analysis results show no significant difference between the fluoroscopic and EM guidance regarding the total procedure time (median 2.36 minutes [interquartile range {IQR} = 1.26-4.7) vs. 2.95 min [IQR = 1.35-5.38], respectively; p = .93); number of total hits with catheter/guidewire tip to vessels wall (median 5.50 [IQR = 2.00-10.00] vs. 3.50 [IQR = 2.50-7.00], respectively; p = .65); and number of attempts at cannulation (median 4.0 [IQR = 2.00-5.00] vs. 4.0 [IQR = 2.00-5.00], respectively; p = .72]. Moreover, there was no significant difference between the IC3ST score obtained using the EM navigator and the traditional method (average 22.37 [STD = 7.95] vs. 21.58 [STD = 6.86]; p = .92). Finally, questionnaire results indicate a general agreement concerning the navigator usefulness, which clearly shows the positions of instruments inside the 3D model of the patient's anatomy. Participants also agreed that the navigator can reduce the amount of contrast media delivered to the patient, as well as fluoroscopy time. This work provides proof of concept that simultaneous EM navigation of guidewires and catheters is feasible without the use of live fluoroscopic images.
    European journal of vascular and endovascular surgery: the official journal of the European Society for Vascular Surgery 10/2013; 47(1). DOI:10.1016/j.ejvs.2013.10.001 · 2.92 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Vessel lumen centerline extraction is important for intraoperative tracking of abdominal vessels and guidance of endovascular instruments. Three-dimensional ultrasound has gained increasing acceptance as a safe and convenient surgical image guidance modality. We aimed to optimize vascular centerline detection and tracking in 3D ultrasound. To overcome the intrinsic limitation of low ultrasound image quality, an active contour method (snake) was used to track changes in vessel geometry. We tested two variants of a classic snake using the image gradient and gradient vector field (GVF) as external forces. We validated these methods in liver ultrasound images of 10 healthy volunteers, acquired at three breath-holding instances during the exhalation phase. We calculated the distances between the vessel centerlines as detected by algorithms and a gold standard consisting of manual annotations performed by an expert. Both methods (GVF and image gradient) can accurately estimate the actual centerlines with average Euclidean distances of 0.77 and 1.24 mm for GVF and gradient, respectively. Both methods can automatically follow vessel morphology and position changes. The proposed approach is feasible for liver vessel centerline extraction from 3D ultrasound images. The algorithm can follow the movement of the vessels during respiration; further improvements of hardware components are needed for a real-time implementation.
    International Journal of Computer Assisted Radiology and Surgery 07/2013; 9(1). DOI:10.1007/s11548-013-0917-4 · 1.36 Impact Factor
  • D. Alghisi, M. Ferrari, V. Ferrari
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents an autonomous battery-less temperature measurement system powered on-demand by human action. The conversion between the human action and electrical energy is provided by an hand-held electromagnetic (EM) converter intentionally activated by the user. The AC voltage generated by the EM converter has time-varying amplitude and frequency and is rectified by a voltage doubler active rectifier circuit. The energy harvested is stored into multiple capacitors by the innovative Sequential Charging of Storage Capacitors (SCSC) technique. With a force of about 29.4 N over 2 cm applied to the EM converter, the power management circuit is able to extract an energy of 27.5 mJ and power the noncontact temperature measurement system for about 17 s.
    Emerging Technologies & Factory Automation (ETFA), 2013 IEEE 18th Conference on; 01/2013
  • M. Ferrari, F. Cerini, V. Ferrari
    [Show abstract] [Hide abstract]
    ABSTRACT: This work proposes and experimentally validates an autonomous battery-less sensor module based on off-the-shelf electronics powered by a multi-beam piezoelectric energy converter that exploits impact to widen the harvesting bandwidth at low frequency. The module manages the converted energy, interfaces two sensors and periodically sends the measurement signals over a radio-frequency (RF) link. The architecture and principle have been experimentally validated on a fabricated proof-of-concept prototype. The solution that exploits impact increases the overall rms output voltage of the converter of up to 35% and widens the useful bandwidth toward lower frequencies of up to 50% over the no-impact condition at parity of mechanical excitation. In the tested experimental conditions, the prototype features a typical time interval between measurement-and-transmission events of a few seconds, with event durations of the order of tens of milliseconds, corresponding to an operation duty cycle of about 1%. The average power consumption during transmission is of the order of 35 mW with an operative range of 25 m in laboratory environment.
    Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS & EUROSENSORS XXVII), 2013 Transducers & Eurosensors XXVII: The 17th International Conference on; 01/2013
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background The da Vinci robotic surgical telemanipulator has been utilized in several surgical specialties for varied procedures, and the users' experiences have been widely published. To date, no detailed system technical analyses have been performed. MethodsA detailed review was performed of all publications and patents about the technical aspects of the da Vinci robotic system. ResultsPublished technical literature on the da Vinci system highlight strengths and weaknesses of the robot design. While the system facilitates complex surgical operations and has a low malfunction rate, the lack of haptic (especially tactile) feedback and collisions between the robotic arms remain the major limitations of the system. Accurate, preplanned positioning of access ports is essential. Conclusion Knowledge of the technical aspects of the da Vinci robot is important for optimal use. We confirmed the excellent system functionality and ease of use for surgeons without an engineering background. Research and development of the surgical robot has been predominant in the literature. Future trends address robot miniaturization and intelligent control design. Copyright (c) 2012 John Wiley & Sons, Ltd.
    International Journal of Medical Robotics and Computer Assisted Surgery 11/2012; 9(4). DOI:10.1002/rcs.1468 · 1.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background Currently, pedicle screws are positioned using a free-hand technique or under fluoroscopic guidance, with error in the range 10-40%, depending on the skill of the surgeon. Methods After spine CT acquisition, each vertebra is segmented and the surgeon plans screw positioning in a virtual environment, then the template is designed around the chosen trajectories. This design is based on surgical and mechanical considerations to obtain an optimal solution to guarantee template stability, simple positioning and minimized intervention invasiveness. In vitro evaluation on synthetic spine models and ex vivo animal tests on porcine specimens were performed, with the insertion of 28 Kirschner wires. ResultsDuring the in vitro tests, all the surgeons rendered positive evaluations regarding the device and considered template placement to be easy. Ex vivo tests were evaluated by CT examination, which showed that 96.5% of the Kirschner wires had been correctly inserted. Conclusions The proposed solution is a promising, simple, highly precise, low-cost solution to safely performing posterior stabilization. Such a solution would be of interest even in hospitals in which a few spine interventions are performed per year, and for which it is not reasonable to purchase the equipment required for robotic or navigated approaches. Copyright (c) 2012 John Wiley & Sons, Ltd.
    International Journal of Medical Robotics and Computer Assisted Surgery 05/2012; 9(3). DOI:10.1002/rcs.1439 · 1.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Endovascular procedures are nowadays limited by difficulties arising from the use of 2D images and are associated with dangerous X-ray exposure and the injection of nephrotoxic contrast medium. An electromagnetic navigator is proposed to guide endovascular procedures with reduced radiation dose and contrast medium injection. Five DOF electromagnetic sensors are calibrated and used to track in real time the positions and orientation of endovascular catheters and guidewires, while intraoperative 3D rotational angiography is used to acquire 3D models of patient anatomy. A preliminary prototype is developed to prove the feasibility of the system using an anthropomorphic phantom. The spatial accuracy of the system was evaluated during 70 targeting trials obtaining an overall accuracy of 1.2 ± 0.3 mm; system usability was positively evaluated by three surgeons. The strategy proposed to sensorize endovascular instruments paves the way for the development of surgical strategies with reduced radiation dose and contrast medium injection. Further in vitro, animal and clinical experiments are necessary for complete surgical validation.
    International Journal of Medical Robotics and Computer Assisted Surgery 02/2012; 8(3):300-10. DOI:10.1002/rcs.1417 · 1.49 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Among the main vibration-to-electricity conversion systems, resonant harvesters suffer from a series of strong limits like their narrow frequency response and poor output power at small scale. Most of all, realistic vibration sources are variable in time and abundant at relatively low frequencies. Nonlinear vibration harvesters, on the other hand, are more attractive, thanks to their large bandwidth response and flexibility to convert kinetic energy of the natural frequency of the sources. In particular, bistable oscillators have been proven to show higher global performances when excited by random vibrations. In this paper, such an approach is investigated for piezoelectric beams by exerting an increasing axial compression. An advantage of this technique is the absence of magnetic forces to create bistable dynamics. A thin piezoelectric axially loaded beam is theoretically modelled and experimentally investigated under wideband random vibrations. In the buckled configuration, the device exhibits superior power generation over a large interval of resistive load, with gains up to more than a factor of ten compared to the unbuckled state. The numerical model and experimental results are in good qualitative agreement.
    Smart Materials and Structures 02/2012; 21(3):035021. DOI:10.1088/0964-1726/21/3/035021 · 2.45 Impact Factor
  • E. Tonoli, M. Baù, M. Ferrari, V. Ferrari
    [Show abstract] [Hide abstract]
    ABSTRACT: Piezoelectric resonator sensors that can be contactless interrogated as passive elements are proposed. The interrogation technique is based on time-gated excitation and detection phases, exploiting the sensing of the transient response of the resonator. The proposed system can be exploited for the measurement of physical or chemical quantities affecting the electromechanical resonant response. In particular, experimental results show the successful interrogation of variable-mass resonator sensors for humidity sensing in closed volumes and submersible resonator sensors operated in liquid environments. (C) 2012 Elsevier Ltd.... Selection and/or peer-review under responsibility of the Symposium Cracoviense Sp. z.o.o.
    Procedia Engineering 01/2012; 47:442-445. DOI:10.1016/j.proeng.2012.09.179
  • [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents an energy harvester based on a bistable clamped-clamped beam to collect energy from wideband vibrational sources at low frequencies. The device exhibits a nonlinear dynamic behaviour which can be described by a double well bistable potential with a switching threshold and two stable equilibrium states. The beam switching is activated by environmental vibrations. The mechanical-to-electrical energy conversion is performed by a screen printed piezoelectric layer electrically connected using InterDigiTed Electrodes (IDT) realized by the inkjet printing of a silver based solution on a flexible PET (PolyEthyleneTerephthalate) substrate through a cheap commercial EPSON (R) inkjet printer. Main advantages of the proposed approach are related to the wide frequency band assuring high device efficiency and low cost technologies adopted to realize both electrodes and the piezoelectric layer. (C) 2012 Elsevier Ltd....Selection and/or peer-review under responsibility of the Symposium Cracoviense Sp. z.o.o.
    Proceedings Eurosensors 2012; 01/2012
  • M. Ferrari, M. Baù, F. Cerini, V. Ferrari
    [Show abstract] [Hide abstract]
    ABSTRACT: This work proposes and experimentally validates a piezoelectric vibration energy harvester, which exploits the impact of a central compliant driving beam onto two piezoelectric parallel bimorph beams on flexible steel. At suitable mechanical excitation conditions, the central driving beam impacts the piezo beams and triggers a nonlinear frequency-up conversion mechanism that improves the overall effectiveness, i.e. increases the overall rms output voltage and widens the equivalent bandwidth of the converter with respect to the condition of the noninteracting linear converters. (C) 2012 Elsevier Ltd.... Selection and/or peer-review under responsibility of the Symposium Cracoviense Sp. z.o.o.
    Procedia Engineering 01/2012; 47:418-421. DOI:10.1016/j.proeng.2012.09.173

Publication Stats

379 Citations
86.84 Total Impact Points

Institutions

  • 2002–2014
    • Università degli Studi di Brescia
      • Department of Information Engineering
      Brescia, Lombardy, Italy
  • 1988–2013
    • Università di Pisa
      • Department of Clinical and Experimental Medicine
      Pisa, Tuscany, Italy
  • 2007
    • Stanford University
      • Department of Chemical Engineering
      Palo Alto, California, United States
    • University of Valencia
      Valenza, Valencia, Spain
  • 2004
    • Azienda Ospedaliero-Universitaria Pisana
      Pisa, Tuscany, Italy
    • Brescia University
      Kenosha, Wisconsin, United States
  • 2003
    • Università degli studi di Parma
      Parma, Emilia-Romagna, Italy
  • 1994
    • National Research Council
      Roma, Latium, Italy