TY - JOUR
T1 - Improved coagulation with saline solution pretreatment during radiofrequency tumor ablation in a canine model
AU - Ahmed, Muneeb
AU - Lobo, S. Melvyn
AU - Weinstein, Joseph
AU - Kruskal, Jonathan B.
AU - Gazelle, G. Scott
AU - Halpern, Elkan F.
AU - Afzal, S. Karim
AU - Lenkinski, Robert E.
AU - Goldberg, S. Nahum
PY - 2002/7
Y1 - 2002/7
N2 - PURPOSE: To determine whether pretreatment with local NaCl injection can increase radiofrequency (RF)-induced coagulation in a large animal model. MATERIAL AND METHODS: Multiple canine venereal sarcomas (n = 25) were implanted subcutaneously in eight mildly immunosuppressed dogs (25 mg/kg cyclosporin A twice daily). Tumors were incubated for 8-12 weeks to a diameter of 4.2-6.3 cm (5.1 cm ± 0.7). Internally cooled RF ablation (1-cm tip; 12 min; pulsed technique; 2,000-mA maximum) was performed. Tumors were pretreated with 6 mL of 18%, 24%, or 36% NaCl injected intratumorally under direct ultrasound guidance after RF electrode insertion, and this treatment was compared to RF treatment without NaCl injection and to 36% NaCl injection without RF ablation. Impedance measurements and remote thermometry were performed. These measurements and resultant coagulation were compared. RESULTS: Significantly greater RF heating (73°C ± 11°C at 20 mm) was observed when the tumors were treated with 24% or 36% NaCl pretreatment, compared to the 47°C ± 5°C observed when 18% or no NaCl was injected (P < .02). In the 36% NaCl group, the entire tumor (5.2 cm ± 0.8 diameter) was completely ablated in every case, with coagulation extending several centimeters into the surrounding tissues. By comparison, control tumors (without NaCl injection) contained coagulation measuring 3.1 cm ± 0.2, surrounded by viable, well-perfused tumor (P < .01), and 36% NaCl alone produced 2.7 cm ± 0.6 of patchy necrosis. CONCLUSIONS: Pretreatment with intratumoral injection of small volumes of highly concentrated NaCl markedly increases RF heating and coagulation in a large animal tumor model. The complete destruction of tumors 5 cm in diameter or larger suggests that this substantial increase may be achieved for tumor ablation in clinical practice.
AB - PURPOSE: To determine whether pretreatment with local NaCl injection can increase radiofrequency (RF)-induced coagulation in a large animal model. MATERIAL AND METHODS: Multiple canine venereal sarcomas (n = 25) were implanted subcutaneously in eight mildly immunosuppressed dogs (25 mg/kg cyclosporin A twice daily). Tumors were incubated for 8-12 weeks to a diameter of 4.2-6.3 cm (5.1 cm ± 0.7). Internally cooled RF ablation (1-cm tip; 12 min; pulsed technique; 2,000-mA maximum) was performed. Tumors were pretreated with 6 mL of 18%, 24%, or 36% NaCl injected intratumorally under direct ultrasound guidance after RF electrode insertion, and this treatment was compared to RF treatment without NaCl injection and to 36% NaCl injection without RF ablation. Impedance measurements and remote thermometry were performed. These measurements and resultant coagulation were compared. RESULTS: Significantly greater RF heating (73°C ± 11°C at 20 mm) was observed when the tumors were treated with 24% or 36% NaCl pretreatment, compared to the 47°C ± 5°C observed when 18% or no NaCl was injected (P < .02). In the 36% NaCl group, the entire tumor (5.2 cm ± 0.8 diameter) was completely ablated in every case, with coagulation extending several centimeters into the surrounding tissues. By comparison, control tumors (without NaCl injection) contained coagulation measuring 3.1 cm ± 0.2, surrounded by viable, well-perfused tumor (P < .01), and 36% NaCl alone produced 2.7 cm ± 0.6 of patchy necrosis. CONCLUSIONS: Pretreatment with intratumoral injection of small volumes of highly concentrated NaCl markedly increases RF heating and coagulation in a large animal tumor model. The complete destruction of tumors 5 cm in diameter or larger suggests that this substantial increase may be achieved for tumor ablation in clinical practice.
KW - Neoplasms, therapy
KW - Radiofrequency (RF) ablation
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U2 - 10.1016/S1051-0443(07)61850-8
DO - 10.1016/S1051-0443(07)61850-8
M3 - Article
C2 - 12119331
AN - SCOPUS:0036079449
SN - 1051-0443
VL - 13
SP - 717
EP - 724
JO - Journal of Vascular and Interventional Radiology
JF - Journal of Vascular and Interventional Radiology
IS - 7
ER -