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Masao Tanooka

Publications and source records attributed to Masao Tanooka.

2 recordsLinked to original sources

Kidney displacement simulator for retroperitoneal laparoscopic nephrectomy.

PURPOSE: We evaluated the efficacy of a renal displacement simulator originally developed at our department for retroperitoneal laparoscopic nephrectomy. MATERIALS AND METHODS: A total of 12 patients with a malignant localized renal (7) or ureteral (5) neoplasm underwent multidetector row computerized tomography. Imaging data were sent to a dedicated work station to create volume rendering and virtual laparoscopic images of the kidney, which was displaced ventral using a retroperitoneal balloon. These findings were compared with video images obtained during laparoscopy surgery. RESULTS: The kidney displacement simulator depicted all renal arteries (100% sensitivity) and 13 of 14 renal veins (93% sensitivity). Hilar anatomy, including the tumor, as well as major vessels and their relationships were visualized by the simulator in the laparoscopic views. The major vessel portions completely corresponded to those seen during surgery, and the left adrenal and gonadal veins were also synchronized quite well. CONCLUSIONS: Our kidney displacement simulator was able to visualize the major vessel portions and branched small vessels, such as the adrenal and gonadal veins, prior to surgery. It is considered useful for providing guidance to surgeons and decreasing operative risks and possible complications.

Aged↗

[Evaluation of gantry tilt correction in multi detector-row CT: effect on multi-planar reconstruction images].

In multi-slice CT, the scanning center of each line multiple-row detector array is shifted in the Y-axis direction by the tilting of the gantry. Correction of this effect is necessary when CT images are reconstructed. Correction of table feed is necessary as well. These corrections are possible with the Somatom Plus4 Volume Zoom. The use of multi-planar reconstruction (MPR) images has been increasing rapidly in the area of clinical diagnosis. Therefore, we examined the influence of MPR images according to gantry tilt. For each gantry tilt, the spatial resolution of MPR images was almost the same even though scanning pitch was changed. When the gantry was tilted, the full width at half maximum (FWHM) of the section sensitivity profile (SSP) was about 10% to 20% wider than that when the gantry was not tilted. The spatial resolution of MPR images is more affected by whether or not the gantry is tilted than by the angle of tilt. Gantry tilt correction is useful to obtain images without artifact for metal and artificial teeth; however, deterioration in spiral resolution cannot be avoided.

Artifacts↗