Dataset Information

Simple calculation using anatomical features on pre-treatment verification CT for bladder volume estimation during radiation therapy for rectal cancer.

ABSTRACT:

Background

Despite detailed instruction for full bladder, patients are unable to maintain consistent bladder filling during a 5-week pelvic radiation therapy (RT) course. We investigated the best bladder volume estimation procedure for verifying consistent bladder volume.

Methods

We reviewed 462 patients who underwent pelvic RT. Biofeedback using a bladder scanner was conducted before simulation and during treatment. Exact bladder volume was calculated by bladder inner wall contour based on CT images (V_ctsim). Bladder volume was estimated either by bladder scanner (V_scan) or anatomical features from the presacral promontory to the bladder base and dome in the sagittal plane of CT (V_ratio). The feasibility of V_ratio was validated using daily megavoltage or kV cone-beam CT before treatment.

Results

Mean V_ctsim was 335.6?±?147.5?cc. Despite a positive correlation between V_ctsim and V_scan (R²?=?0.278) and between V_ctsim and V_ratio (R²?=?0.424), V_ratio yielded more consistent results than V_scan, with a mean percentage error of 26.3 (SD 19.6, p?ratio and V_ctsim was stronger than that between V_scan and V_ctsim (Z-score: -?7.782, p?ratio was consistent in megavoltage or kV cone-beam CT during treatment. In a representative case, we can dichotomize for clinical scenarios with or without bowel displacement, using a ratio of 0.8 resulting in significant changes in bowel volume exposed to low radiation doses.

Conclusions

Bladder volume estimation using personalized anatomical features based on pre-treatment verification CT images was useful and more accurate than physician-dependent bladder scanners.

Trial registration

Retrospectively registered.

SUBMITTER: Kim N

PROVIDER: S-EPMC7528380 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Publications

Simple calculation using anatomical features on pre-treatment verification CT for bladder volume estimation during radiation therapy for rectal cancer.

Kim Nalee N Yoon Hong In HI Kim Jin Sung JS Koom Woong Sub WS Chang Jee Suk JS Chung Yoonsun Y

BMC cancer 20201001 1

<h4>Background</h4>Despite detailed instruction for full bladder, patients are unable to maintain consistent bladder filling during a 5-week pelvic radiation therapy (RT) course. We investigated the best bladder volume estimation procedure for verifying consistent bladder volume.<h4>Methods</h4>We reviewed 462 patients who underwent pelvic RT. Biofeedback using a bladder scanner was conducted before simulation and during treatment. Exact bladder volume was calculated by bladder inner wall contou ...[more]

PMID: 33004026

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Dataset Information

Simple calculation using anatomical features on pre-treatment verification CT for bladder volume estimation during radiation therapy for rectal cancer.

Background

Methods

Results

Conclusions

Trial registration

Publications

Simple calculation using anatomical features on pre-treatment verification CT for bladder volume estimation during radiation therapy for rectal cancer.

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