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Y Kutsutani-Nakamura

Publications and source records attributed to Y Kutsutani-Nakamura.

11 recordsLinked to original sources
PubMed1996

[Method of calculating TDF biological equivalent for optimal treatment dose in fractionated intracavitary irradiation of carcinoma of the uterine cervix].

Intracavitary irradiation therapy for carcinoma of the uterine cervix used with high or low dose rate irradiation is fractionated in Japan. The optimal treatment dose is determined according to the biological effect on both diseased and healthy tissues. The equations of modified NSD and TDF biological equivalents were recalculated from Arai's clinical data, which were used to examine the optimal time-dose-fractionation relationship for high and low dose rate intracavitary irradiation on squamous cell carcinoma of the cervix uteri. The optimal time-dose-fractionation relationship at point A is expressed as follows: D = NSD N0.26 T0.06 where NSD is 17.75 get for high dose rate and 31.78 get for low dose rate. TDF = K n d1.47 x-0.09 where K is 1.46 for high dose rate and 0.62 for low dose rate. The range of the optimal total dose to point A given by one fraction per week was 30.7 Gy for 4 fractions and 38.3 Gy for 8 fractions in high dose rate irradiation. In the case of low dose rate irradiation, the optimal total dose given by one fraction per week and the dose rate of 75.0 cGy/h was 55.0 Gy for 4 fractions. The maximum dose difference between our result and Arai's was about +/- 10%. The dose modification ratio for high dose rate and low dose rate is 1.79.

Brachytherapy↗
PubMed1990

[Determination of the point position from two orthogonal X-ray photographs using least squares method and geometrical solutions].

Six sets of solutions for calculating the position of an interest point were obtained geometrically using four measured image coordinates on two X-ray photographs orthogonally projected. When the image coordinates had no error, all the solutions gave the same position without error. When an error occurred, the calculated positions differed from each other due to the propagation of error. Some solutions could not be used for this determination owing to a large propagation of error. Under conditions similar to those of clinical practice, the ratio of maximum error of position calculated by the six geometrical solutions to minimum error was about 426. The least squares method that we proposed gave results with less error. When one of the image coordinates could not be measured for some reason, the least squares method became automatically equivalent to one of the six geometrical solutions.

Image Processing, Computer-Assisted↗
PubMed1988

A method for calculating the optimum irradiation condition for intracavitary radiotherapy using quadratic programming.

A method of calculating optimum irradiation conditions for intracavitary radiotherapy using quadratic programming has been formulated and then modified for practical application. The allowable range of obtained dose, which is usually fixed in advance, is automatically computed to be as small as possible. The variance of the product of the activity and the irradiation time of the tandem source is also minimised to avoid the occurrence of cold and/or hot spots. Optimum irradiation conditions for conventional intracavitary radiotherapy of carcinoma of the uterine cervix were obtained on the basis of isodose curves passed through the points A of the Manchester system. Those for carcinoma of the other organs and special cases of carcinoma of the uterine cervix can be determined after consideration of the tumour state.

Brachytherapy↗
PubMedDate not supplied

Two-radiograph reconstruction using six geometrical solution sets and least-squares method.

When two radiographic projections are available for reconstruction, it was found that six different combinations of equations could be used to obtain the geometrical solutions for the position of any point. No errors in the image coordinates read from the radiographs resulted in identical solutions for the six equations. Inaccuracies or errors present in the image coordinates generated differences among the six solutions. In this case, a least-squares method could be used to determine the optimum position. The utility of such a least-squares optimizing approach is presented in the context of a clinical example.

Brachytherapy↗