Magnetic instruments for laparoscopic surgery have the potential to enhance triangulation and reduce invasiveness, as they can be rearranged inside the abdominal cavity and do not need a dedicated port during the procedure. Onboard actuators can be used to achieve a controlled and repeatable motion at the interface with the tissue. However, actuators that can fit through a single laparoscopic incision are very limited in power and do not allow performance of surgical tasks such as lifting an organ. In this study, we present a tissue retractor based on local magnetic actuation (LMA). This approach combines two pairs of magnets, one providing anchoring and the other transferring motion to an internal mechanism connected to a retracting lever. Design requirements were derived from clinical considerations, while finite element simulations and static modeling were used to select the permanent magnets, set the mechanism parameters, and predict the lifting and supporting capabilities of the tissue retractor. A three-tier validation was performed to assess the functionality of the device. First, the retracting performance was investigated via a benchtop experiment, by connecting an increasing load to the lever until failure occurred, and repeating this test for different intermagnetic distances. Then, the feasibility of liver resection was studied with an ex vivo experiment, using porcine hepatic tissue. Finally, the usability and the safety of the device were tested in vivo on an anesthetized porcine model. The developed retractor is 154 mm long, 12.5 mm in diameter, and weights 39.16 g. When abdominal wall thickness is 2 cm, the retractor is able to lift more than ten times its own weight. The model is able to predict the performance with a relative error of 9.06 ± 0.52%. Liver retraction trials demonstrate that the device can be inserted via laparoscopic access, does not require a dedicated port, and can perform organ retraction. The main limitation is the reduced mobility due to the length of the device. In designing robotic instrument for laparoscopic surgery, LMA can enable the transfer of a larger amount of mechanical power than what is possible to achieve by embedding actuators on board. This study shows the feasibility of implementing a tissue retractor based on this approach and provides an illustration of the main steps that should be followed in designing a LMA laparoscopic instrument.

References

References
1.
Scott
,
D. J.
,
Tang
,
S. J.
,
Fernandez
,
R.
,
Bergs
,
R.
,
Goova
,
M. T.
,
Zeltser
,
I.
,
Kehdy
,
F. J.
, and
Cadeddu
,
J. A.
, 2007, “Completely Transvaginal NOTES Cholecystectomy Using Magnetically Anchored Instruments,”
Surg. Endoscopy
,
21
(12), pp.
2308
2316
.10.1007/s00464-007-9498-z
2.
Best
,
S. L.
,
Kabbani
,
W.
,
Scott
,
D. J.
,
Bergs
,
R.
,
Beardsley
,
H.
,
Fernandez
,
R.
, and
Cadeddu
,
J. A.
,
2011
, “
Magnetic Anchoring and Guidance System Instrumentation for Laparo-Endoscopic Single-Site Surgery/Natural Orifice Transluminal Endoscopic Surgery: Lack of Histologic Damage After Prolonged Magnetic Coupling Across the Abdominal Wall
,”
Urology
,
77
(
1
), pp.
243
247
.10.1016/j.urology.2010.05.041
3.
Park
,
S.
,
Bergs
,
R. A.
,
Eberhart
,
R.
,
Baker
,
L.
,
Fernandez
,
R.
, and
Cadeddu
,
J. A.
,
2007
, “
Trocar-Less Instrumentation for Laparoscopy: Magnetic Positioning of Intra-Abdominal Camera and Retractor
,”
Ann. Surg.
,
245
(
3
), pp.
379
384
.10.1097/01.sla.0000232518.01447.c7
4.
Padilla
,
B. E.
,
Dominguez
,
G.
,
Millan
,
C.
, and
Martinez-Ferro
,
M.
,
2011
, “
The Use of Magnets With Single-Site Umbilical Laparoscopic Surgery
,”
Semin. Pediatr. Surg.
,
20
(
4
), pp.
224
231
.10.1053/j.sempedsurg.2011.05.007
5.
Zeltser
,
I. S.
,
Bergs
,
R.
,
Fernandez
,
R.
,
Baker
,
L.
,
Eberhart
,
R.
, and
Cadeddu
,
J. A.
,
2007
, “
Single Trocar Laparoscopic Nephrectomy Using Magnetic Anchoring and Guidance System in the Porcine Model
,”
J. Urol.
,
178
(
1
), pp.
288
291
.10.1016/j.juro.2007.03.001
6.
Cadeddu
,
J.
,
Fernandez
,
R.
,
Desai
,
M.
,
Bergs
,
R.
,
Tracy
,
C.
,
Tang
,
S. J.
, and
Scott
,
D.
,
2009
, “
Novel Magnetically Guided Intra-Abdominal Camera to Facilitate Laparoendoscopic Single-Site Surgery: Initial Human Experience
,”
Surg. Endoscopy
,
23
(
8
), pp.
1894
1899
.10.1007/s00464-009-0459-6
7.
Lehman
,
A. C.
,
Dumpert
,
J.
,
Wood
,
N. A.
,
Redden
,
L.
,
Visty
,
A. Q.
,
Farritor
,
S.
, and
Oleynikov
,
D.
,
2009
, “
Natural Orifice Cholecystectomy Using a Miniature Robot
,”
Surg. Endoscopy
,
23
(
2
), pp.
260
266
.10.1007/s00464-008-0195-3
8.
Tortora
,
G.
,
Dario
,
P.
, and
Menciassi
,
A.
,
2014
, “
Array of Robots Augmenting the Kinematics of Endocavitary Surgery
,”
IEEE/ASME Trans. Mechatronics
,
19
(
6
), pp.
1821
1829
.10.1109/TMECH.2013.2296531
9.
Simi
,
M.
,
Silvestri
,
M.
,
Cavallotti
,
C.
,
Vatteroni
,
M.
,
Valdastri
,
P.
,
Menciassi
,
A.
, and
Dario
,
P.
,
2013
, “
Magnetically Activated Stereoscopic Vision System for Laparoendoscopic Single-Site Surgery
,”
IEEE/ASME Trans. Mechatronics
,
18
(
3
), pp.
1140
1151
.10.1109/TMECH.2012.2198830
10.
Vartholomeos
,
P.
,
Bergeles
,
C.
,
Qin
,
L.
, and
Dupont
,
P. E.
,
2013
, “
An MRI-Powered and Controlled Actuator Technology for Tetherless Robotic Interventions
,”
Int. J. Rob. Res.
,
32
(
13
), pp.
1536
1552
.10.1177/0278364913500362
11.
Heller
,
J. A.
,
Kwiat
,
D.
,
Fechter
,
R.
,
Harrison
,
M. R.
,
Roy
,
S.
,
Liu
,
J. A.
, and
Etemadi
,
M.
,
2012
, “
ROBOImplant II: Development of a Noninvasive Controller/Actuator for Wireless Correction of Orthopedic Structural Deformities
,”
ASME J. Med. Devices
,
6
(
3
), p.
031006
.10.1115/1.4007183
12.
Di Natali
,
C.
,
Ranzani
,
T.
,
Simi
,
M.
,
Menciassi
,
A.
, and
Valdastri
,
P.
,
2012
, “
Trans-Abdominal Active Magnetic Linkage for Robotic Surgery: Concept Definition and Model Assessment
,”
IEEE International Conference on Robotics and Automation
(
ICRA
), Saint Paul, MN, May 14–18, pp.
695
700
.10.1109/ICRA.2012.6225081
13.
Di Natali
,
C.
, and
Valdastri
,
P.
,
2012
, “
Remote Active Magnetic Actuation for a Single-Access Surgical Robotic Manipulator
,”
Int. J. Comput. Assisted Radiol. Surg.
,
7
(S1), pp.
S169
S171
.10.1007/s11548-012-0716-3
14.
Best
,
S. L.
,
Bergs
,
R.
,
Gedeon
,
M.
,
Paramo
,
J.
,
Fernandez
,
R.
,
Cadeddu
,
J. A.
, and
Scott
,
D. J.
,
2011
, “
Maximizing Coupling Strength of Magnetically Anchored Surgical Instruments: How Thick Can We Go?
,”
Surg. Endoscopy
,
25
(
1
), pp.
153
159
.10.1007/s00464-010-1149-0
15.
Steris
,
1994
, “
AMSCO Evolution Floor Loader
,” Steris Corp., Mentor, OH, http://www.steris.com/products/steam-sterilizer/amsco-evolution-floor-loader
16.
Beckerman
,
P.
, and
Ma
,
J.
,
2006
, “
A Compact, Modular, Teleoperated Robotic Minimally Invasive Surgery System
,”
First IEEE/RAS-EMBS International Conference on Biomedical Robotics and Biomechatronics
(
BioRob 2006
), Pisa, Italy, Feb. 20–22, pp.
702
707
.10.1109/BIOROB.2006.1639172
17.
Wood
,
N. A.
,
2008
,
Design and Analysis of Dexterous In Vivo Robots for NOTES
,
University of Nebraska–Lincoln
,
Lincoln, NE
.
18.
Canes
,
D.
,
Lehman
,
A. C.
,
Farritor
,
S. M.
,
Oleynikov
,
D.
, and
Desai
,
M. M.
,
2009
, “
The Future of NOTES Instrumentation: Flexible Robotics and In Vivo Minirobots
,”
J. Endourology
,
23
(
5
), pp.
787
792
.10.1089/end.2008.0318
19.
Gan
,
P.
,
2014
, “
A Novel Liver Retractor for Reduced or Single-Port Laparoscopic Surgery
,”
Surg. Endoscopy
,
28
(
1
), pp.
331
335
.10.1007/s00464-013-3178-y
20.
Furlani
,
E. P.
,
2001
, “
Permanent Magnet and Electromechanical Devices: Materials, Analysis, and Applications
,” Academic, San Diego, CA.
21.
Agashe
,
J. S.
, and
Arnold
,
D. P.
,
2008
, “
A Study of Scaling and Geometry Effects on the Forces Between Cuboidal and Cylindrical Magnets Using Analytical Force Solutions
,”
J. Phys. D: Appl. Phys.
,
41
(
10
), p.
105001
.10.1088/0022-3727/41/10/105001
22.
Ikuta
,
K.
,
Makita
,
S.
, and
Arimoto
,
S.
,
1991
, “
Non-Contact Magnetic Gear for Micro Transmission Mechanism
,” IEEE Micro Electro Mechanical Systems (
MEMS'91
), Nara, Japan, Jan. 30–Feb. 2, pp.
125
130
.10.1109/MEMSYS.1991.114782
23.
Simi
,
M.
,
Gerboni
,
G.
,
Menciassi
,
A.
, and
Valdastri
,
P.
,
2013
, “
Magnetic Torsion Spring Mechanism for a Wireless Biopsy Capsule
,”
ASME J. Med. Devices
,
7
(
4
), p.
041009
.10.1115/1.4025185
24.
Sudano
,
A.
,
Accoto
,
D.
,
Zollo
,
L.
, and
Guglielmelli
,
E.
,
2013
, “
Design, Development and Scaling Analysis of a Variable Stiffness Magnetic Torsion Spring
,”
Int. J. Adv. Rob. Syst.
,
10
(
372
), pp.
1
11
.10.5772/57300
25.
Montague
,
R.
,
Bingham
,
C.
, and
Atallah
,
K.
,
2012
, “
Servo Control of Magnetic Gears
,”
IEEE/ASME Trans. Mechatronics
,
17
(
2
), pp.
269
278
.10.1109/TMECH.2010.2096473
26.
Namiki,
1999
, “
Coreless Motors: φ 10 mm
,” Namiki Precision Jewel Co. Ltd., Tokyo, Japan, accessed June 26, 2014, http://www.namiki.net/product/dcmotor/coreless.html
27.
Faulhaber,
1997
, “
DC-Micromotors: φ 10 mm
,” Faulhaber Miniature Drive System, Schönaich, Germany, accessed June 26, 2014, https://www.fmcc.faulhaber.com/type/PGR_13813_13801/PGR_13818_13813/en/
28.
Maxon Motor,
2011
, “
DC Motors and Drive System: φ 10 mm & Torque 2–5 mNm
,” Maxon Motor AG, Brünigstrasse, Switzerland, accessed June 26, 2014, http://www.maxonmotor.com/maxon/view/catalog
29.
Chowdhury
,
A. M.
,
Nuruzzaman
,
D. M.
,
Mia
,
A. H.
, and
Rahaman
,
M. L.
,
2012
, “
Friction Coefficient of Different Material Pairs Under Different Normal Loads and Sliding Velocities
,”
Tribol. Ind.
,
34
(
1
), pp.
18
23
.
30.
Brewer
,
R. D.
,
Loewke
,
K. E.
,
Duval
,
E. F.
, and
Salisbury
,
J. K.
,
2008
, “
Force Control of a Permanent Magnet for Minimally-Invasive Procedures
,”
2nd IEEE RAS & EMBS International Conference on Biomedical Robotics and Biomechatronics
(
BioRob 2008
), Scottsdale, AZ, Oct. 19–22, pp.
580
586
.10.1109/BIOROB.2008.4762819
You do not currently have access to this content.