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1.

Purpose

To evaluate the influence of percutaneous cryoablation for renal cell carcinoma on function of the affected kidney.

Materials and Methods

Between June 2016 and September 2017 at our institution, 12 inoperable patients underwent 15 cryoablation sessions for 17 small renal tumors. Of these, 9 patients who underwent 11 sessions of cryoablation were the focus of this study. For those patients, time-dependent changes in postoperative renal function were investigated by a retrospective review of clinical records. Evaluated were the estimated glomerular filtration rate (eGFR) and scintigraphy using 99m technetium-mercaptoacetyltriglycine (99mTc-MAG3) before and 1 week, 1–2 months, and more than 6 months after cryoablation.

Results

Mean baseline eGFR was 76.88 ± 29.82 mL/min/1.73 m2 (mean ± standard deviation; range, 23.4–112.5). Mean eGFR 1 week, 1–2 months, and more than 6 months after cryoablation were 74.56 ± 26.68 mL/min/1.73 m2 (21.0–101.1), 69.5 ± 25.28 mL/min/1.73 m2 (24.1–105.6), and 75.08 ± 26.25 mL/min/1.73 m2 (29.0–107.3), respectively. Changes were statistically insignificant (P = .6044, P = .6699, and P = .9038, respectively). Regarding split renal function, the mean baseline contribution of the affected kidney determined by 99mTc-MAG3 was 47.27% ± 6.14 (38.8%–57.0%). Mean contributions of the affected kidney 1 week after, 1–2 months after, and more than 6 months after cryoablation were 44.40% ± 5.37 (38.3%–53.6%), 44.57% ± 6.52 (34.35%–55.0%), and 45.41% ± 7.77 (34.4%–56.5%), respectively. Differences from baseline were significant for the earliest 2 periods (P = .0473 and P = .0334, respectively) but not the later period (P = .2532).

Conclusions

Results suggested that total renal function does not worsen after cryoablation; however, function of the affected kidney worsened after cryoablation but later partially recovered.  相似文献   
2.
DHS is characterized by chin-on-chest deformity and devastatingly impedes activities of daily living in affected individuals. There is a paucity of literature about the pathophysiology of DHS including knowledge about spinal sagittal alignment. We conducted this study to clarify the relationship between cervical sagittal alignment and global sagittal balance in DHS. This is a retrospective radiographic study of a case series of DHS. Forty-one patients with diagnosed DHS were enrolled. Measurements were made using lateral standing radiograph. C2–C7 sagittal vertical axis (SVA) was estimated as 52.0 ± 2.4 mm. Among sagittal parameters, C7–S1 SVA positively correlated with C2–C7 angle (C2–C7 A) (r = 0.33). For the correlations between C7 and S1 SVA and C2–C7 A, both logistic and linear regression models were used to determine the threshold for C2–C7 A value responsible for global sagittal balance. C2–C7 A of − 15.0 and 6.0 were predicted by logistic and linear regression models and were considered responsible for the occurrence of global positive imbalance. Therefore, we divided into two groups, namely, cervical kyphosis group (C type) and diffuse kyphosis group (D type) by median value of C2–C7 A. Enlarged thoracic kyphosis and global positive imbalance were observed in D type compared to C type. C2–C7 A exhibited correlations with cervical balance and also with global balance. There should be various type of thoraco-lumbar alignment in DHS. These slides can be retrieved under Electronic Supplementary Material.  相似文献   
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Purpose

Suppression of respiratory movement of the liver would be desirable for high-precision radiation therapy for liver tumors. We aimed to investigate the effect of our original device-free compressed shell fixation method and breathing instruction on suppression of respiratory movement. The characteristics of liver motion based on the movement of a fiducial marker were also analyzed.

Methods and Materials

First, respiratory amplitudes of the liver with the device-free compressed shell were analyzed from the data of 146 patients. The effect of this shell fixing method on liver movement was evaluated. Second, as another cohort study with 166 patients, interfractional internal motion of the liver for patients fixed in the shell was calculated using the fiducial marker coordinate data of images for position setting before daily irradiation. Third, in another 12 patients, intrafractional internal motion was calculated from the fiducial marker coordinate data using x-ray images before and after irradiation.

Results

The median respiratory movement without the shell, after fixing with the shell, and after instructing on the breathing method with the shell was 14.2 (interquartile range, 10.7-19.8), 11.5 (8.6-17.5), and 10.4 mm (7.3-15.8), respectively. Systematic and random errors of interfractional internal motion were all ≤2 mm in the left-right and anteroposterior directions and 3.7 and 3.0 mm, respectively, in the craniocaudal direction. Systematic and random errors of intrafractional internal motion were all ≤1.3 mm in the left-right and anteroposterior directions and 0.8 and 2.4 mm, respectively, in the craniocaudal direction.

Conclusions

The device-free compressed shell fixation method was effective in suppressing the respiratory movement of the liver. Irradiation position matching using the fiducial marker can correct the interfractional internal motion on each day, which would contribute to the reduction of the margin to be given around the target.  相似文献   
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