Pathologic Analysis of Tissue Destruction with Neutral Argon Plasma
Madhuri TK1, Butler-Manuel SA1, Tailor A1 & Haagsma B2
1Department
of Gynaecological Oncology, 2Department of Histopathology
Royal Surrey County Hospital NHS Foundation Trust, Guildford, UK
Background
Results from Sigmoid Bowel Table 2
DTD varied from 0.2 -3.5mm (mean 1.29)
LTS was minimal at all the settings ranging from 0.1-0.4(mean: 0.22)
Tissue damage at the base of the cavity ranged from 0.07 to 0.4 (mean 0.15)
Various electrosurgical devices have been developed to coagulate tissues
and achieve haemostasis. Both conventional electrosurgery and the argon
beam coagulator (ABC) employ a monopolar current passing though the
patient. Plasmajet (PJ) is a novel electrically neutral device which uses a
jet of high energy Argon Plasma for direct tissue effects. Energy is
dissipated as light, kinetic energy and heat and PJ may be used for tissue
dissection, coagulation of small vessels and even vapourization of tissues
depending on the distance from the tissues, time of application and power
setting used.
Aim
Leiomyoma Figure 1 showing
cavity at 40% setting (3sec)
Leiomyoma Figure 2 showing
eschar at 40% setting (3sec)
Figure 3 showing cavity
at 40% setting (1sec)
Figure 4 showing cavity
at 40% setting (5sec)
Figure 5 showing eschar
at 40% setting (1sec)
Figure 6 showing eschar
at 40% setting (5sec)
The aim of this study is to investigate the histopathological effects of tissue
destruction (TD) and lateral thermal spread (LTS) following PJ use at
different power settings used and tissue interaction time at a fixed distance
of 1cm.
Materials & Methods
The study was performed in 3 phases using the same PJ handpiece and
console. Consent was obtained from all women and tissue obtained at
surgery was subjected to the PJ at different power settings and time
duration. Initially this was performed on uterine fibroids. Subsequently, from
women undergoing debulking for EOC, fresh tissue was harvested intraoperatively from the sigmoid bowel following anterior resection. Following
tissue excision, 1cm3 sections of tissue was exposed to PJ at varied power
settings and increasing time duration. These were formalin-fixed and
stained. Histological examination of tissue destruction included assessment
of cavity depth and extent of burn at the base of cavity..
Lateral thermal spread is remarkably constant and predictable with PJ
tissue destruction, despite changes in power used. Increasing both
power and tissue interaction time resulted in a deeper crater of tissue
vapourization but with constant size of surrounding eschar.
Discussion
We previously reported the use of PJ for various applications in benign and
malignant gynaecological procedures and these uniques tissue properties
may well be of use in other specialties.1 In ovarian cancer debulking where
optimal cytoreduction is desired, but many tumour deposits are on the
surface of vital organs, the PJ appears to effectively vaporize cancer cells
effectively. Minimal LTS and DTD is necessary especially when ablating
tumour deposits around viscera and bowel surfaces.
Results
144 specimens were analysed. These included 48 specimens each from a
uterus (hysterectomy specimen for benign leiomyomata), omentum and from
the sigmoid colon following anterior resection.
Depth of Tissue Destruction
DTD was defined by the depth of the cavity left by the ablated tissue.
Conclusion
Lateral Thermal Spread
LTS was defined by the depth of histologically visible tissue damage. This
was measured from the surface of the eschar to the level of normal tissue
morphology.
Leiomyoma Results Table 1
DTD for leiomyoma varied from 0.2 -3.48mm (mean 2.25mm)
LTS was minimal at all the settings mentioned. (mean: 0.38 range 0.24 to 1)
Tissue damage at the base of the cavity ranged from 0.1-0.22 (mean 0.17)
The above data suggests that the PJ has unique properties which
render it inherently safe and well suited to may be used optimal
cytoreduction of metastatic ovarian cancer. An RCT to assess the role
of this device including assessment of cost-effectiveness has been
setup further evaluation.
References
1. Madhuri TK, Papatheodorou D, Tailor A, Sutton CJG, Butler-Manuel SA.
First clinical experience of argon neutral plasma energy in gynaecological surgery in the UK. Gynecol
Surg. 2010:7(4):423-425
Table 1 showing the results of PJ use on leiomyomas
Cavity
Eschar
Cavity
Eschar
Superficial Margin (mm)
Cavity Base
(mm)
Depth (mm)
0.2
0.15
0.1
0.5
0.3
1.3
0.3
0.1
1
0.35
3
2
0.45
0.2
1.5
0.3
Exposure Time
(Seconds)
Depth (mm)
1
2
Superficial Margin
(mm)
Cavity
Cavity Base
(mm)
Eschar
Cavity
Depth (mm)
Superficial Margin
(mm)
Cavity Base
(mm)
0.2
0.7
0.25
0.14
1.45
0.35
0.2
1.75
Eschar
Depth (mm)
Superficial Margin
(mm)
Cavity Base
(mm)
0.22
1
0.25
0.1
0.2
1.25
0.24
0.2
0.35
0.15
1.57
0.24
0.22
5
2.25
0.4
0.15
4.25
0.45
0.2
3.1
0.47
0.13
2.25
0.4
0.2
7
3.5
0.44
0.1
3
0.4
0.13
3.3
0.51
0.15
3.05
0.25
0.15
9
4.5
0.6
0.19
3.9
1
0.14
3.6
0.65
0.16
3.48
0.25
0.22
Power Setting
10%
20%
40%
60%
Table 2 showing the results of examination of the tumour tissue (serous carcinoma from sigmoid bowel)
Cavity
Exposure Time
(Seconds)
Depth
(mm)
1
0.45
2
0.2
3
0.3
4
0.4
Power Setting
Corresponding
Eschar
Superficial
Margin
(mm)
Cavity
Eschar
Superficial
Margin
(mm)
Cavity Base
(mm)
Depth (mm)
0.1
0.4
0.2
0.1
0.15
0.1
0.6
0.15
0.2
0.13
0.4
0.2
0.4
0.1
0.2
0.21
10%
20%
Cavity
Eschar
Cavity
Eschar
Depth (mm)
Superficial
Margin
(mm)
Cavity Base
(mm)
Depth (mm)
Superficial
Margin (mm)
0.08
1
0.35
0.15
0.6
0.18
0.07
1.2
0.3
0.11
1
0.25
0.17
1.5
0.23
0.12
3.5
0.25
0.17
3.5
0.4
0.08
2.75
0.32
Cavity Base
(mm)
40%
60%
Cavity
Cavity
Base
(mm)
Eschar
Depth (mm)
Superficial Margin
(mm)
Cavity Base
(mm)
0.3
1
0.12
0.1
0.15
1.25
0.18
0.12
0.2
2.25
0.25
0.2
0.15
3.5
0.25
0.15
80%
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