Yukio Honma

Laser Ureterolithotripsy with Combined Rigid and Flexible Ureterorenoscopy

Because the pulsed dye laser can be transmitted through a thin, flexible quartz fiber a small caliber ureteroscope and flexible ureterorenoscope are applicable. Therefore, the use of a rigid or flexible ureterorenoscope was combined with laser lithotripsy to treat upper urinary tract calculi. All 14 ureteral stones below the pelvic brim were removed successfully with a rigid 7.2F (outer diameter) ureteroscope and 14 of 16 stones above the pelvic brim were removed with a flexible ureterorenoscope. Laser monotherapy was effective in 24 cases and the complementary use of forceps or electrohydraulic lithotripsy was required in 4. Two stones were lost from the visual field during endoscopic manipulation. There was no complication requiring surgical correction. The combined use of these instruments is highly successful and safe for the treatment of upper urinary tract calculi.

Robust servoing method for renal stones/tumors for the non-invasive ultrasound theragnostic system

The main problem on HIFU (High Intensity Focused Ultrasound) therapy is the difficulty to locate HIFU focus precisely onto the focal lesion, which is located in the moving organ such as livers/kidneys, due to the deformation and rotation, which is caused by respiration. Furthermore, rib bones frequently block the acoustic path to the lesion. The acoustic shadow, which is generated by the rib bone, is observed in the ultrasound images and the lesion is hidden in the shadow. To cope with this problem, we have developed a novel method to track, follow, and monitor the lesion by utilizing the contour information of the organ, which incorporate the lesion under those difficult conditions. As for the tracking method, the contour of the organ, which is deformed and rotated in accordance with respiration, is extracted automatically in 2-D ultrasound images. The missing contour information in the acoustic shadow area is estimated and compensated by the surrounding contours, which are successfully extracted. To con...

A CASE OF THYMOMA ASSOCIATED WITH PROSTATIC CANCER

A case of prostatic cancer treated with an LH-RH analogue depo-preparation was found to have a mediastinal thymoma which was later removed by surgery. The association of thymoma and prostatic cancer has not been documented in the world literature, and it remains to be elucidated whether the occurrence of the both tumors is a coincidence or etiologically inter-related.