1. Application of microwave energy in cardiac tissue ablation: from in vitro analyses to clinical use 
Mathew R Williams, MD, Michael Knaut, MD, Dany Bérubé, PhD, Mehmet C Oz, MD 
The Annals of Thoracic Surgery 
Volume 74, Issue 5, Pages (November 2002)
DOI: /S (02)

2. Fig 1 Microwave ablation system. Close-up of ablating probe [inset].
The Annals of Thoracic Surgery  , DOI: ( /S (02) )

3. Fig 2
Specific absorption rate (SAR) pattern showing microwave energy intensity produced by the ablating probe. The horizontal axis represents the distance along the ablating probe, whereas the vertical axis represents depth within the liquid phantom. The proximal end of the ablating probe was located at Z = 4 mm, and the distal end at Z = 29 mm. Normalized SAR values indicate maximal energy deposition, which was obtained at the interface between the ablating probe and phantom.
The Annals of Thoracic Surgery  , DOI: ( /S (02) )

4. Fig 3
Thermal profiles obtained with microwave energy power application of 40 W for 8, 16, and 24 seconds, respectively. Proximal end of the ablating probe was located at 0 mm, the distal end at 20 mm (x-axis). Lesion depth is given on the y-axis and isotherms are expressed in degrees Celsius. The zone of irreversible tissue damage begins at the 50°C isotherm line.
The Annals of Thoracic Surgery  , DOI: ( /S (02) )

5. Fig 4
Temperature elevation (°C) demonstrated by solid phantom modeling with application of 40 W microwave power over 24 seconds at specified tissue depths (0, 2, 4, and 6 mm). Temperatures over time were similar at the solid phantom surface and 2 mm deep. Tissue temperature sufficient for a 4-mm-deep lesion (50°C) occurred with 12 to 13 seconds of ablation, and for a 6-mm-deep lesion with 24 seconds of ablation, while surface temperature remained below 100°C.
The Annals of Thoracic Surgery  , DOI: ( /S (02) )

6. Fig 5
Average lesion penetration depths achieved with application of 40 W microwave energy for 10, 25, and 40 seconds. Penetration depth was successively and significantly deeper with increased ablation time.
The Annals of Thoracic Surgery  , DOI: ( /S (02) )

7. Fig 6
Cross section of a lesion produced using a power application of 40 W for 25 seconds. Although not apparent here, the length of the lesion was approximately 25 mm, corresponding to the length of the microwave energy antenna.
The Annals of Thoracic Surgery  , DOI: ( /S (02) )