This work describes the mechanical and the electromagnetic design of a microwave surface applicator used to coagulate liver tissue in the treatment of hepatic tumors. A good prediction of the ratio between reflected and forward microwave power (return loss) is obtained with a finite element model using commercial software. Laboratory testing of the applicator performed in polyacrylamide gel (PAG) and in ex vivo bovine liver show a hemispherical heat distribution pattern and hemispherical ablations up to 20 mm in diameter and 15 mm in depth in a controlled manner in 1 min. The applicator can also be used to coagulate larger areas of tissue with 2–5 mm depth by moving the applicator on the surface of the tissue. Experimental results indicate that the coagulated volume of tissue is approximately proportional to the energy delivered into ex vivo bovine liver, hemispherical in shape, obtained in short time duration with a volumetric rate of coagulated tissue of about 50 mm3/s.

References

References
1.
Hamady
,
Z. Z. R.
,
Kotru
,
A.
,
Nishio
,
H.
, and
Lodge
,
P. A.
, 2004, “
Current Techniques and Results of Liver Resection for Colorectal Liver Metastases
,”
Br. Med. Bull.
,
70
, pp.
87
104
.
2.
Tanabe
,
G.
,
Sakamoto
,
M.
,
AkAzawak
,
K.
,
Kurita
,
K.
,
Hamanoue
,
M.
,
Uenos
,
S.
,
Kobayashia
,
Y.
,
Mitue
,
S.
,
Ogura
,
Y.
,
Yoshidome
,
N.
,
Baba
,
M.
, and
Aikou
,
T.
, 1995, “
Intraoperative Risk-Factors Associated With Hepatic Resection
,”
Br. J. Surg.
,
82
, pp.
1262
1265
.
3.
Kooby
,
D. A.
,
Stockman
,
J.
,
Ben-Porat
,
L.
,
Gonen
,
M.
,
Jarnagin
,
W. R.
,
Dematteo
,
R. P.
,
Tuorto
,
S.
,
Wuest
,
D.
,
Blumgart
,
L. H.
, and
Fong
,
Y.
, 2003, “
Influence of Transfusions on Perioperative and Long-Term Outcome in Patients Following Hepatic Resection for Colorectal Metastases
,”
Ann. Surg.
,
237
, pp.
860
870
.
4.
Fortner
,
J. G.
, and
Blumgart
,
L. H.
, 2001, “
A Historic Perspective of Liver Surgery for Tumors at the End of the Millennium
,”
J. Am. Coll. Surg.
,
193
, pp.
210
222
.
5.
Takatsuki
,
M.
,
Eguchi
,
S.
,
Yamanouchi
,
K.
,
Tokai
,
H.
,
Hidaka
,
M.
,
Soyama
,
A.
,
Miyazaki
,
K.
,
Hamasaki
,
K.
,
Tajima
,
Y.
, and
Kanematsu
,
T.
, 2009, “
Two-Surgeon Technique Using Saline-Linked Electric Cautery and Ultrasonic Surgical Aspirator in Living Donor Hepatectomy: Its Safety and Efficacy
,”
Am. J. Surg.
,
197
, pp.
25
27
.
6.
Poon
,
R. T.
,
Fan
,
S. T.
, and
Wong
,
J.
, 2005, “
Liver Resection Using a Saline-Linked Radiofrequency Dissecting Sealer for Transection of the Liver
,”
J. Am. Coll. Surg.
,
200
, pp.
308
313
.
7.
Stavrou
,
G. A.
,
Donati
,
M.
,
Fruehauf
,
N. R.
,
Flemming
,
P.
, and
Oldhafer
,
K. J.
, 2009, “
Liver Resection Using Heat Coagulative Necrosis: Indications and Limits of a New Method
,”
ANZ J. Surg.
,
79
(9)
, pp.
628
634
.
8.
Peralta
,
A. U.
,
Pirani
,
N.
,
Clegg
,
P.
,
Cronin
,
N.
,
Ryan
,
T. P.
,
Liu
,
Z.
, and
Goldberg
,
N.
, 2006, “
Microwave Ablation: Results With a 2.45-GHz Applicator in Ex Vivo Bovine and in vivo Porcine Liver
,”
Radiology
,
239
, pp.
94
102
.
9.
Bhardwaj
,
N.
,
Strickland
,
A. D.
,
Ahmad
,
F.
,
Atanesyan
,
L.
,
West
,
K.
, and
Lloyd
,
D. M.
, 2009, “
A Comparative Histological Evaluation of the Ablations Produced By Microwave, Cryotherapy and Radiofrequency in the Liver
,”
Pathology
,
41
, pp.
168
172
.
10.
Ong
,
S. L.
,
Gravante
,
G.
,
Metcalfe
,
M. S.
,
Strickland
,
A. D.
,
Dennison
,
A. R.
, and
Lloyd
,
D. M.
, 2009, “
Efficacy and Safety of Microwave Ablation for Primary and Secondary Liver Malignancies: A Systematic Review
,”
Eur. J. Gastroenterol. Hepatol.
,
21
, pp.
599
605
.
11.
Strickland
,
A. D.
,
Clegg
,
P.
,
Cronin
,
N.
,
Swift
,
B.
,
Festing
,
M.
,
West
,
K. P.
,
Roberston
,
G. S. M.
, and
Lloyd
,
D. M.
, 2002, “
Experimental Study of Large-Volume Microwave Ablation in The Liver
,”
Br. J. Surg.
,
89
, pp.
1003
1007
.
12.
Pozar
,
D.
, 2005,
Microwave Engineering
,
Wiley
,
New York
.
13.
Christel
,
P. S.
, 1992, “
Biocompatibility of Surgical Grade Dense Polycrystalline Alumina
,”
Clin. Orth. Related Res.
,
282
, pp.
10
17
.
14.
Piatelli
,
P.
,
Podda
,
G.
, and
Scarano
,
A.
, 1996, “
Histological Evaluation of Bone Reactions to Aluminium Oxide Dental Implants in Man: A Case Report
,”
Biomaterials
,
17
, pp.
711
714
.
15.
Piconi
,
C.
, and
Maccauro
,
G.
, 1999, “
Zirconia As a Ceramic Biomaterial
,”
Biomaterials
,
20
, pp.
1
25
.
16.
Manicone
,
P. F.
,
Iommetti
,
R. R.
, and
Raffaeli
,
L.
, 2007, “
An Overview of Zirconia Ceramics: Basic Properties and Clinical Applications
,”
J. Dentistry
,
35
, pp.
819
826
.
17.
Comsol, Comsol version 3.3, AC/DC module. www.comsol.com.
18.
Saxton
,
J.
, and
Lane
,
J.
, 1952, “
Properties of Seawater
,”
Wireless Eng.
,
29
, pp.
269
275
.
19.
Andreucetti
,
D.
,
Bini
,
M. G.
,
Ignesti
,
A.
,
Olmi
,
R.
,
Rubino
,
N.
, and
Vanni
,
R.
, 1998, “
Use of Polyacrylamide As a Tissue-Equivalent Material in the Microwave Range
,”
IEEE Trans. Biomed. Eng.
,
35
, pp.
275
277
.
20.
Bini
,
M. G.
,
Ignesti
,
A.
,
Millanta
,
L.
,
Olmi
,
R.
,
Rubino
,
N.
, and
Vanni
,
R.
, 1984, “
The Polyacrylamide As a Phamtom Material for Electromagnetic Hyperthermia Studies
,”
IEEE Trans. Biomed. Eng.
,
31
, pp.
317
322
.
You do not currently have access to this content.