[Percutaneous layer differentiation of the colonic wall by ultrasound. Clinical case examples and experimental...

Based on 3 case observations, the feasibility of the percutaneous sonographic objectivation of a five-layer image of the colon wall using a 5 Mhz linear transducer is reported for the first time. Sonographic stratification is promoted by means of "ultrasound windows" or contrasting borderlines. Employing stepwise dissection of autoptic specimens and ultrasonic comparison, it was possible to identify the hypodense zones 2 and 4 as mucous membrane and muscle layer, divided by the reflecting submucous layer (zone 3). The hyperdense bands 1 and 5 were found to represent borderline echos of the large bowel wall. This preliminary report is a step towards an eventual percutaneous staging of colon neoplasms.