title: Enhanced torque-based impedance control to assist brain targeting during open-skull neurosurgery: a feasibility study.
abstract: BACKGROUND
  Cooperatively-controlled robotic assistance could provide increased positional accuracy and stable and safe tissue targeting tasks during open-skull neurosurgical procedures, which are currently performed free-hand.
  
  
  METHODS
  Two enhanced torque-based impedance control approaches, i.e. a variable damping criterion and a force-feedback enhancement control, were proposed in combination with an image-based navigation system. Control systems were evaluated on brain-mimicking phantoms by 13 naive users and 8 neurosurgeons (4 novices and 4 experts).
  
  
  RESULTS
  In addition to a 60% reduction of user effort, the combination of the proposed strategies showed comparable performances with respect to state-of-the-art admittance controller, thus satisfying the clinical accuracy requirements (below 1 mm), reducing the hand tremor (by a factor of 10) and the tissue's indentation overshooting (by 80%).
  
  
  CONCLUSIONS
  Although the perceived reliability of the system should be improved, the proposed control was suitable to assist targeting procedures, such as brain cortex stimulation, allowing for accurate, stable and safe contact with soft tissues. Copyright © 2015 John Wiley & Sons, Ltd.
authors.affiliation: Electronics, Information and Bioengineering Department, Politecnico di Milano, p.zza Leonardo da Vinci 32, 2013, Milan, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Beretta
authors.affiliation: Electronics, Information and Bioengineering Department, Politecnico di Milano, p.zza Leonardo da Vinci 32, 2013, Milan, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Nessi
authors.affiliation: Electronics, Information and Bioengineering Department, Politecnico di Milano, p.zza Leonardo da Vinci 32, 2013, Milan, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Ferrigno
authors.affiliation: Neurosurgery Department, Fondazione I.R.C.C.S. Istituto Neurologico "C. Besta", Milano, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Di Meco
authors.affiliation: Neurosurgery Department, Fondazione I.R.C.C.S. Istituto Neurologico "C. Besta", Milano, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Perin
authors.affiliation: NeuroOncological Surgery, Università degli Studi di Milano, Humanitas Research Hospital, IRCCS, Rozzano, Milan, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Bello
authors.affiliation: "Claudio Munari" Center for Epilepsy and Parkinson Surgery, Niguarda Hospital, Piazza Ospedale Maggiore, 3, 20162, Milan, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Casaceli
authors.affiliation: "Claudio Munari" Center for Epilepsy and Parkinson Surgery, Niguarda Hospital, Piazza Ospedale Maggiore, 3, 20162, Milan, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Raneri
authors.affiliation: Neurosurgery Unit, Bambino Gesù Children's Hospital, Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: De Benedictis
authors.affiliation: Electronics, Information and Bioengineering Department, Politecnico di Milano, p.zza Leonardo da Vinci 32, 2013, Milan, Italy.
authors.forename: E
authors.initials: E
authors.lastname: De Momi
mesh_terms: D017097:Electric Impedance; D005069:Evaluation Studies as Topic; D005240:Feasibility Studies; D006801:Humans; D019635:Neurosurgical Procedures / Q000379:methods*; D065287:Robotic Surgical Procedures; D012886:Skull / Q000601:surgery*; D019415:Torque
keywords: cooperative control; robotic neurosurgery; targeting task