[Evaluation of colon diseases by using new method of extracorporeal ultrasonic examination during usual colon endoscopy]

Generally two types of ultrasonic colon examination method are carried out. One is extracorporeal ultrasonographic examination (US). And another is endoscopic ultrasonographic examination (EUS). US is technically easy but is difficult to take good image of colon diseases. EUS can give us good and sufficient informations. But it is technically difficult and gives much trouble to patients. During usual endoscopy, we have tried extracorporeal ultrasonic examination by filling de-aired water around the diseased colon area. With this new method, we could easily identify the disease and got much better picture than usual US. And this new method gave almost no trouble and pain to examinees in comparison with EUS.

[Newly developed ultrasonic micro-probe (15MHz), basic and clinical study for gastrointestinal lesions]

The authors evaluated a new device the ultrasonic micro-probe (2.4mm in the outer diameter, radial scanning system, 15MHz, Toshiba Co.) from both its basic and clinical aspects using resected gastric specimens and clinical subjects. The ultrasonic resolution of this new ultrasound imaging catheter was demonstrated to be best the probe-object distance was 1.0-3.0mm and angle of inclination was 0-20. On clinical use of the probe, the above-mentioned basic evaluation is important to achieve high resolution ultrasonic image. For attenuation of ultrasound due to the high-frequency (15MHz), the main subjects of this probe for evaluation of gastrointestinal tract are small lesions of mucosal-submucosal layers. Because of its small caliber (2.4mm), the micro-probe can be passed through the biopsy channel of common used endoscope, and permits the intra-luminal ultrasound examination at routine endoscopy, if necessary. This new device the ultrasonic micro-probe will develop the ability of endoscopic ultrasound in diagnosing gastrointestinal disorders.