Focused Liver Ablation by Cavitation in the Rabbit: a Potential New Method of Extracorporeal Treatment
Overview
Affiliations
A new device was used to achieve focused tissue ablation by shockwave induced cavitation. The device produced a half cycle of negative pressure followed by a shock wave, thus enhancing cavitation. Twenty eight New Zealand rabbits were treated. Therapeutic ultrasound was targeted at the centre of the liver under ultrasound guidance. The focal volume was scanned with a computer operated x-y-z micropositioner. The number and frequency of bursts as well as the distance between two x-y-z displacements were preselected. The relation of tissue ablation seen to preselected parameters, effects on surrounding tissues, biological side effects, and mode of healing were studied. Macroscopy, planimetry, and quantitative microscopy were used. Focused and homogeneous tissue ablation was achieved within well defined limits. Maximal tissue ablation was seen in the centre of the target. Liver surrounding the target remained unaffected. Lesions were made of a-cellular spots surrounded by disorganised rims of necrotic hepatocytes; 24 hours after treatment, the changes (mean (SEM)) in alanine transaminase and haemoglobin were +225 (36)% and -2.4 (2)% respectively. Serum transaminases, haemoglobinaemia, and packed cell volume were normal 21 days after treatment and the target area was replaced by a fibrous scar. It is concluded that ultrasound cavitation may achieve extracorporeal intrahepatic tissue ablation inside a predetermined target. This technique should now be tested in an animal hepatic tumour model.
The histotripsy spectrum: differences and similarities in techniques and instrumentation.
Williams R, Simon J, Khokhlova V, Sapozhnikov O, Khokhlova T Int J Hyperthermia. 2023; 40(1):2233720.
PMID: 37460101 PMC: 10479943. DOI: 10.1080/02656736.2023.2233720.
Xu Z, Hall T, Vlaisavljevich E, Lee Jr F Int J Hyperthermia. 2021; 38(1):561-575.
PMID: 33827375 PMC: 9404673. DOI: 10.1080/02656736.2021.1905189.
Ultrastructural observation of liver tissue ablation induced by high-intensity focused ultrasound.
Cheng S, Zhou X, Tang Z, Yu Y, Bao S, Qian D World J Gastroenterol. 2016; 3(3):134-6.
PMID: 27239124 PMC: 4842865. DOI: 10.3748/wjg.v3.i3.134.
Quantitative ultrasound backscatter for pulsed cavitational ultrasound therapy- histotripsy.
Wang T, Xu Z, Winterroth F, Hall T, Fowlkes J, Rothman E IEEE Trans Ultrason Ferroelectr Freq Control. 2009; 56(5):995-1005.
PMID: 19750596 PMC: 3130252. DOI: 10.1109/tuffc.2009.1131.
Distinct sensitivity of normal and malignant cells to ultrasound in vitro.
Lejbkowicz F, Salzberg S Environ Health Perspect. 1998; 105 Suppl 6:1575-8.
PMID: 9467085 PMC: 1469937. DOI: 10.1289/ehp.97105s61575.