[Evaluation of a training system for middle ear surgery with optoelectric detection].
OBJECTIVE
This work presents a new training concept for surgery of the temporal bone. It is based on a model of gypsum plastic with optoelectric detection of risk structures. A prototypical evaluation is given.


METHODS
The training models are based on high-resolution computed tomographic data of a human skull. The resulting data set was printed by a three-dimensional (3D) printer. A 3D phantom is created from gypsum powder and a bonding agent. Risks structures are the facial nerve, semicircular canal, cochlea, ossicular chain, sigmoid sinus, dura, and internal carotid artery. An electrically conductive metal (Wood's metal) and a fiber-optic cable were used as detection materials for the risk structures. For evaluating the training system, a study was done with eight inexperienced and eight experienced ear surgeons. They were asked to perform temporal bone surgery using two identical training models (group A). In group B, the same surgeons underwent surgical training with human cadavers. In the case of injuries, the number, point in time, degree (facial nerve), and injured structure were documented during the training on the model. In addition, the total time needed was noted.


RESULTS
The training systems could be used in all cases. Evaluation of the anatomic accuracy of the models showed results that were between 49.5% and 90% agreement with the anatomic origin. Error detection was evaluated with values between 79% and 100% agreement with the perception of an experienced surgeon. The operating setting was estimated to be better than the previous"gold standard." The possibility of completely replacing the previous training method, which uses cadavers, with the examined training model was affirmed.


CONCLUSIONS
This study shows that the examined system fulfills the conditions for a new training concept for temporal bone surgery. The system connects the preliminary work with printed and sintered models with the possibilities of microsystem engineering. In addition, the model's digital database permits a complete virtual representation of the model with appropriate further applications ("look behind the wall," virtual endoscopy).
Strauss
G
G
Klinik und Poliklinik für HNO-Heilkunde/Plastische Operationen, Innovation Center Computer Assisted Surgery (ICCAS) der Universität, Liebigstrasse 10-14, 04103, Leipzig. Gero.Strauss@medizin.uni-leipzig.de
Bahrami
N
N
Pössneck
A
A
Strauss
M
M
Dietz
A
A
Korb
W
W
Lüth
T
T
Haase
R
R
Moeckel
H
H
Grunert
R
R
D003194:Computer-Assisted Instruction / Q000379:methods*; D004432:Ear, Middle / Q000601:surgery*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005858:Germany; D006801:Humans; D008348:Manikins; D010027:Osteotomy / Q000193:education* / Q000379:methods; D013517:Otorhinolaryngologic Surgical Procedures / Q000193:education* / Q000379:methods; D025321:Surgery, Computer-Assisted / Q000295:instrumentation* / Q000379:methods*
Otol Neurotol. 2002 Nov;23(6):832-5
12438841
HNO. 1998 Mar;46(3):246-51
9583030
HNO. 2006 Dec;54(12):947-57
16625370
J Am Coll Surg. 2004 Jan;198(1):105-10
14698317
Ergonomics. 2002 Apr 15;45(5):362-79
12028721
Laryngorhinootologie. 2003 Oct;82(10):683-6
14593565
Otol Neurotol. 2001 Jul;22(4):451-6
11449098
Acta Otolaryngol. 2004 May;124(4):400-2
15224862
Clin Otolaryngol Allied Sci. 1997 Aug;22(4):355-7
9298612
Laryngorhinootologie. 2004 Jun;83(6):363-6
15197675
ORL J Otorhinolaryngol Relat Spec. 2006;68(2):115-7
16446558
Laryngorhinootologie. 2005 May;84(5):335-44
15909245
Laryngoscope. 2007 Mar;117(3):434-41
17334303
Stud Health Technol Inform. 2003;94:4-10
15455854
Laryngoscope. 1994 Aug;104(8 Pt 1):922-6
8052074
Conf Proc IEEE Eng Med Biol Soc. 2006;2006:4408-11
17945837
Eur Arch Otorhinolaryngol. 2007 Jun;264(6):595-9
17235531
Am J Surg. 2002 Sep;184(3):291-5
12354602
J Am Coll Surg. 2001 Dec;193(6):660-5
11768683
Surgery. 2002 Mar;131(3):318-23
11894037
ORL J Otorhinolaryngol Relat Spec. 2002 Nov-Dec;64(6):378-81
12499759
Otolaryngol Head Neck Surg. 2005 Dec;133(6):911-5
16360513
J Laryngol Otol. 1997 Feb;111(2):113-6
9102433
Laryngoscope. 2007 Feb;117(2):258-63
17204992