Image-guided thermochemical ablation: theoretical and practical considerations.
OBJECTIVE
To test thermochemical ablation for potential as a new method to coagulate tissue and create a prototype device for administration.


METHODS
Reactions of either HCl or acetic acid and either NH4OH or NaOH were run in triplicate in a gel phantom as a simple calorimeter. Data were recorded over a period of 5 minutes using concentrations from 1-12 M in the case of HCl and NH4OH. Comparison reactions were run at 11 M using each acid reacted with each base. Two early device prototypes were devised using readily available components.


RESULTS
Maximum temperature rise was nearly instantaneous and was observed to peak with the 12 M solutions at 106 degrees C. The maximum temperatures in the 11 M comparisons were seen with the strong acid HCl paired with the strong base NaOH. The lowest temperatures were seen with the weak acid acetic acid paired with the weak base NH4OH.


CONCLUSIONS
Thermochemical ablation reactions can release adequate amounts of heat energy to cause tissue ablation.
Cressman
Erik N K
EN
University of Minnesota Medical School, Minneapolis, MN 55455, USA. cress013@umn.edu
D055011:Ablation Techniques; D019342:Acetic Acid / Q000737:chemistry; D064753:Ammonium Hydroxide; D002151:Calorimetry / Q000379:methods; D004867:Equipment Design; D005782:Gels; D006358:Hot Temperature; D006801:Humans; D006851:Hydrochloric Acid / Q000737:chemistry; D006878:Hydroxides / Q000737:chemistry; D006979:Hyperthermia, Induced / Q000295:instrumentation / Q000379:methods*; D008422:Materials Testing; D019047:Phantoms, Imaging; D012972:Sodium Hydroxide / Q000737:chemistry; D025321:Surgery, Computer-Assisted; D013816:Thermodynamics
D005782:Gels; D006878:Hydroxides; D064753:Ammonium Hydroxide; D012972:Sodium Hydroxide; D019342:Acetic Acid; D006851:Hydrochloric Acid