ISSN:
1435-604X
Keywords:
YAG laser
;
Hyperthermia
;
Liver cell necrosis
;
Therapy
;
Metastasis
;
Focal lesions
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
,
Physics
,
Technology
Notes:
Abstract A solitary hepatic metastasis is amenable to surgery. However, if surgery is contraindicated or if multiple lesions are present in both liver lobes, other treatment modalities have to be considered. We compared the effect of interstitial laser hyperthermia with damage caused by alcoholization. Six anaesthetized beagle dogs were studied. Three animals were treated with laser hyperthermia. A bare laser fibre (400μm diameter) was introduced through a 17-gauge needle, length 170 mm, positioned into the liver under real time ultrasonographic guidance. Lesions were produced by continuous 500-s exposure of 1W YAG laser (Medilas MBB 40N) power. Three dogs were subjected to an injection of 4 ml of 98% pure ethanol into the liver through the same needle system. Two days after the procedure the animals were killed and the livers examined. The surface of the livers treated with the YAG laser were entirely normal; superficial lesions were, however, clearly visible. Laserinduced lesions were well reproducible, clearly demarcated, roughly spherical with a mean diameter of 1.01±0.23 cm (n=16). In contrast, the dogs treated with alcohol had free intraperitoneal serohaemorrhagic fluid and the surface of the liver was diffusely abnormal. The lesions had a more or less cylindrical shape, 1.22±0.43 cm on 0.40±0.10 cm (n=12) although exact measurement was often difficult. The border of the lesions was irregular and there was a clear necrotic zone along the puncture track. On microscopic examination the laser-induced lesions consisted of a central evaporation area, a zone of carbonized material and an outer zone of coagulation necrosis. The alcohol-induced lesions were characterized by both ‘fixation’ necrosis and coagulative necrosis but surprisingly, there was also necrosis present at a distance of the lesions extending along the centrilobular and even portal veins. These data show that laser-induced interstitial necrosis in the liver is better controlled and more reproducible than necrosis induced by injection of pure ethanol. Moreover, pure ethanol may cause damage to the liver surface and even at a distance of the injection site.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02042644
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