01.12.2017 | Research | Ausgabe 1/2017 Open Access

# Magnitude and influencing factors of respiration-induced liver motion during abdominal compression in patients with intrahepatic tumors

- Zeitschrift:
- Radiation Oncology > Ausgabe 1/2017

## Introduction

## Materials and methods

### Patients

### Abdominal compression

### 4D-CT image acquisition

### Liver displacement acquisition and analysis

_{Contour10}, Copy

_{Contour20}…Copy

_{Contour90}. There were 10 liver contours (Copy

_{Contour10}, Copy

_{Contour20}…Copy

_{Contour90}and liver contours of CT0) on the CT0 image. Then, 0- and 90° digitally reconstructed radiographic beams were added to the CT0 image. 0- and 90° digitally reconstructed radiographic images were a set of coronal and sagittal projections. Ten liver 3-dimensional (3D) contours could be projected onto the digitally reconstructed radiographic images in the directions of 0 and 90°. Overlays of 10 liver contours were shown on the digitally reconstructed radiographic images of 0 and 90°. The relative coordinates of the liver were automatically generated to calculate the respiratory liver motion in three different anatomical directions. The position for each liver was expressed using the left-right (LR), CC, and anterior-posterior (AP) coordinates of the center of mass (COM) for each 4D-CT bin. Then, the range in respiratory liver motion from the COM of each coordinate was obtained. Maximum range of motion in each axial direction was calculated by subtracting the minimum relative coordinate value from the maximum relative coordinate value.

### Formulas

### Statistical analyses

Clinicopathological factors | Breath amplitude in CC direction |
p-value | |
---|---|---|---|

≤5 mm | >5 mm | ||

Gender, n (%) | |||

Male | 17 (41.5%) | 24 (58.5%) | 0.041* |

Female | 9 (75.0%) | 3 (25.0%) | |

Age, n (%) | |||

≤ 50 y | 11 (55.0%) | 9 (45.0%) | 0.500 |

> 50 y | 15 (45.5%) | 18 (54.5%) | |

BMI, n (%) | |||

< 25 kg/m ^{2}
| 23 (62.2%) | 14 (37.8%) | 0.004* |

≥ 25 kg/m ^{2}
| 3 (18.7%) | 13 (81.3%) | |

TACE, n (%) | |||

Yes | 15 (51.7%) | 14 (48.3%) | 0.669 |

No | 11 (45.8%) | 13 (54.2%) | |

Postoperative recurrence, n (%) | |||

Yes | 10 (45.5%) | 12 (54.5%) | 0.659 |

No | 16 (51.6%) | 15 (48.4%) | |

Liver tumor location, n (%) | |||

Right lobe | 18 (50.0%) | 18 (50.0%) | 0.691 |

Left lobe | 2 (33.3%) | 4 (66.7%) | |

Left and right lobe | 6 (54.5%) | 5 (45.5%) | |

Intrahepatic lesions, n (%) | |||

Solitary | 15 (48.4%) | 16 (51.6%) | 0.908 |

Multiple | 11 (50.0%) | 11 (50.0%) | |

Tumor diameter, n (%) | |||

≤ 5 cm | 19 (48.7%) | 20 (51.3%) | 0.934 |

> 5 cm | 7 (50.0%) | 7 (50.0%) |

Parameter | Multivariate Analysis | ||
---|---|---|---|

OR | 95% CI |
p-value | |

Gender | |||

Male | 1 | 0.030* | |

Female | 7.450 | 1.221–45.473 | |

BMI | |||

≥ 25 kg/m ^{2}
| 1 | 0.006* | |

< 25 kg/m ^{2}
| 10.842 | 2.012–58.434 |

## Results

### Respiratory liver motion during abdominal compression

### Predictors of effectiveness of abdominal compression

### The optimal cut-off value for BMI

^{2}, as shown in Fig. 2. When repeating the multivariate logistic regression analysis of the association between BMI and AC effectiveness using the optimal cut-off BMI value of 25.15 kg/m

^{2}, the p-value was 0.006 and 95% CI was 2.012–58.434, which were the same results obtained using the original BMI cut-off value of 25 kg/m

^{2}.

### Correlation between body mass index and gender

^{2}for the females and 23.26 ± 3.44 kg/m

^{2}for the males. There was no significant difference between these values (p = 0.821). No correlation was detected between BMI and gender. This supports the multivariate analysis findings that BMI and gender were independent factors influencing the effectiveness of AC.