Cochlear implants have become a standard treatment for many with severe to profound sensorineural hearing loss. However, delicate cochlear structures can be damaged during surgical insertion, which can lead to loss of residual hearing and decreased implant effectiveness. We propose a magnetic guidance concept in which a magnetically tipped cochlear implant is guided as it is inserted into the cochlea. In a scaled in vitro experimental study, we record insertion forces for nonguided and magnetically guided insertion experiments and compare the results. Results indicate that magnetic guidance reduced insertion forces by approximately 50%. Using first principles, we discuss the effects of scaling down our in vitro experiments, and account for realistic clinical dimensions. We conclude that scale–down effects are negligible, but to produce the same field strength as in our experiments and provide sufficient clearance between the patient and the manipulator, the magnet dimensions should be increased by approximately four times.

References

References
1.
Rebscher
,
S. J.
,
Hetherington
,
A.
,
Bonham
,
B.
,
Wardrop
,
P.
,
Whinney
,
D.
, and
Leake
,
P. A.
, 2008, “
Considerations for Design of Future Cochlear Implant Electrode Arrays: Electrode Array Stiffness, Size, and Depth of Insertion
,”
J. Rehabil. Res. Dev.
,
45
(
5
), pp.
731
747
.
2.
Briggs
,
R. J. S.
,
Tykocinski
,
M.
,
Saunders
,
E.
,
Hellier
,
W.
,
Dahm
,
M.
,
Pyman
,
B.
, and
Clark
,
G. M.
, 2001, “
Surgical Implications of Perimodiolar Cochlear Implant Electrode Design: Avoiding Intracochlear Damage and Scala Vestibuli Insertion
,”
Cochlear Implants Int.
,
2
(
2
), pp.
135
149
.
3.
Adunka
,
O.
, and
Kiefer
,
J.
, 2006, “
Impact of Electrode Insertion Depth on Intracochlear Trauma
,”
Otolaryngol. Head Neck Surg.
,
135
(
3
), pp.
374
382
.
4.
Gstoettner
,
W.
,
Franz
,
P.
,
Hamzavi
,
J.
,
Plenk
,
H.
,
Baumgartner
,
W.
, and
Czerny
,
C.
, 1999, “
Intracochlear Position of Cochlear Implant Electrodes
,”
Acta Otolaryngol.
,
119
(
2
), pp.
229
233
.
5.
Gstoettner
,
W. K.
,
Adunka
,
O.
,
Franz
,
P.
,
Hamzavi
,
J.
,
Plenk
,
H.
,
Susani
,
M.
,
Baumgartner
,
W.
, and
Kiefer
,
J.
, 2001, “
Perimodiolar Electrodes in Cochlear Implant Surgery
,”
Acta Otolaryngol.
,
121
(
2
), pp.
216
219
.
6.
Roland
, Jr.,
J. T.
, 2005, “
A Model for Cochlear Implant Electrode Insertion and Force Evaluation: Results With a New Electrode Design and Insertion Technique
,”
Laryngoscope
,
115
(
8
), pp.
1325
1339
.
7.
Todd
,
C. A.
,
Naghdy
,
F.
, and
Svehla
,
M. J.
, 2007, “
Force Application During Cochlear Implant Insertion: An Analysis for Improvement of Surgeon Technique
,”
IEEE Trans. Biomed. Eng.
,
54
(
7
), pp.
1247
1255
.
8.
Schurzig
,
D.
,
Webster
III,
R. J.
,
Dietrich
,
M. S.
, and
Labadie
,
R. F.
, 2010, “
Force of Cochlear Implant Electrode Insertion Performed by a Robotic Insertion Tool: Comparison of Traditional Versus Advance Off-Stylet Techniques
,”
Otol. Neurotol.
,
31
(
8
), pp.
1207
1210
.
9.
Mirzadeh
,
H.
, and
Abbasi
,
F.
, 2004, “
Segmented Detachable Structure of Cochlear-Implant Electrodes for Close-Hugging Engagement With the Modiolus
,”
J. Biomed. Mater. Res. B Appl. Biomater.
,
68B
(
2
), pp.
191
198
.
10.
Arcand
,
B. Y.
,
Bhatti
,
P. T.
,
Butala
,
N. V.
,
Wang
,
J.
,
Friedrich
,
C. R.
, and
Wise
,
K. D.
, 2004, “
Active Positioning Device for a Perimodiolar Cochlear Electrode Array
,”
Microsys.Tech.
,
10
(6)
, pp.
478
483
.
11.
Wu
,
J.
,
Yan
,
L.
,
Xu
,
H.
,
Tang
,
W. C.
, and
Zeng
,
F.-G.
, 2005, “
A Curvature-Controlled 3D Micro-Electrode Array for Cochlear Implants
,”
IEEE 13th International Conference on Solid-State Sensors, Actuators and Microsystems, TRANSDUCERS ’05, Vol. 2, Seoul, Korea, June 5–9
, pp.
1636
1639
.
12.
Chen
,
B.
,
Kha
,
H. N.
, and
Clark
,
G. M.
, 2007, “
Development of a Steerable Cochlear Implant Electrode Array
,” 3rd Kuala Lumpur International Conference on Biomedical Engineering 2006
(IFMBE Proceedings)
, Vol.
15
pp.
607
610
.
13.
Zhang
,
J.
,
Roland
, Jr.,
J. T.
,
Manolidis
,
S.
, and
Simaan
,
N.
, 2009, “
Optimal Path Planning for Robotic Insertion of Steerable Electrode Arrays in Cochlear Implant Surgery
,”
ASME J. Med. Devices
,
3
(
1
), p.
011001
.
14.
Zhang
,
J.
,
Wei
,
W.
,
Ding
,
J.
,
Roland
, Jr.,
J. T.
,
Manolidis
,
S.
, and
Simaan
,
N.
, 2010, “
Inroads Toward Robot-Assisted Cochlear Implant Surgery Using Steerable Electrode Arrays
,”
Otol. Neurotol.
,
31
(
8
), pp.
1199
1206
.
15.
Majdani
,
O.
,
Schurzig
,
D.
,
Hussong
,
A.
,
Rau
,
T.
,
Wittkopf
,
J.
,
Lenarz
,
T.
, and
Labadie
,
R. F.
, 2010, “
Force Measurement of Insertion of Cochlear Implant Electrode Arrays in Vitro: Comparison of Surgeon to Automated Insertion Tool
,”
Acta Otolaryngol.
,
130
(
1
), pp.
31
36
.
16.
Schurzig
,
D.
,
Labadie
,
R. F.
,
Hussong
,
A.
,
Rau
,
T. S.
, and
Webster
III,
R. J.
, 2012, “
Design of a Tool Integrating Force Sensing With Automated Insertion in Cochlear Implantation
,”
IEEE/ASME Trans. Mechatronics
,
17
(2)
, pp.
381
389
.
17.
Clark
,
J. R.
,
Warren
,
F. M.
, and
Abbott
,
J. J.
, 2011, “
A Scalable Model for Human Scala-Tympani Phantoms
,”
ASME J. Med. Devices
,
5
(
1
), p.
014501
.
18.
Maghribi
,
M. N.
,
Krulevitch
,
P. A.
,
Davidson
,
J. C.
, and
Hamilton
,
J. K.
, 2006, “
Implantable Devices Using Magnetic Guidance
,” U.S. Patent No. 0052656.
19.
Abbott
,
J. J.
,
Ergeneman
,
O.
,
Kummer
,
M. P.
,
Hirt
,
A. M.
, and
Nelson
,
B. J.
, 2007, “
Modeling Magnetic Torque and Force for Controlled Manipulation of Soft–Magnetic Bodies
,”
IEEE Trans. Robot.
,
23
(
6
), pp.
1247
1252
.
20.
Zeng
,
F.-G.
,
Rebscher
,
S.
,
Harrison
,
W.
,
Sun
,
X.
, and
Feng
,
H.
, 2008, “
Cochlear Implants: System Design, Integration, and Evaluation
,”
IEEE Rev. Biomed. Eng.
,
1
, pp.
115
142
.
21.
Ishii
,
T.
,
Takayama
,
M.
, and
Takahashi
,
Y.
, 1995, “
Mechanical Properties of Human Round Window, Basilar and Reissner’s Membranes
,”
Acta Otolaryngol.
,
115
(
s519
), pp.
78
82
.
22.
Kha
,
H. N.
, and
Chen
,
B. K.
, 2006, “
Determination of Frictional Conditions Between Electrode Array and Endosteum Lining for Use in Cochlear Implant Models
,”
J. Biomech.
,
39
(
9
), pp.
1752
1756
.
23.
Howell
,
L. L.
, 2001,
Compliant Mechanisms
,
John Wiley & Sons, Inc.
, New York.
24.
Teissl
,
C.
,
Kremser
,
C.
,
Hochmair
,
E. S.
, and
Hochmair-Desoyer
,
I. J.
, 1999, “
Magnetic Resonance Imaging and Cochlear Implants: Compatibility and Safety Aspects
,”
J. Magn. Reson. Imaging
,
9
(
1
), pp.
26
38
.
25.
Gubbels
,
S. P.
, and
McMenomey
,
S. O.
, 2006, “
Safety Study of the Cochlear Nucleus 24 Device With Internal Magnet in the 1.5 Tesla Magnetic Resonance Imaging Scanner
,”
Laryngoscope
,
116
(
6
), pp.
865
871
.
26.
Crane
,
B. T.
,
Gottschalk
,
B.
,
Kraut
,
M.
,
Aygun
,
N.
, and
Niparko
,
J. K.
, 2010, “
Magnetic Resonance Imaging at 1.5 T After Cochlear Implantation
,”
Otol. Neurotol.
,
31
(
8
), pp.
1215
1220
.
You do not currently have access to this content.