Limits...
Evaluation of Renal Oxygenation Level Changes after Water Loading Using Susceptibility-Weighted Imaging and T2* Mapping.

Ding J, Xing W, Wu D, Chen J, Pan L, Sun J, Xing S, Dai Y - Korean J Radiol (2015)

Bottom Line: Both medullary phase and medullary T2(*) values increased after water loading (p < 0.001), although poor correlations were found between the phase changes and the T2(*) changes (p > 0.05).The area under receiver operating characteristic curve of the SWI medullary phase values was 0.85 and was not different from the medullary T2(*) value (0.84).Susceptibility-weighted imaging enabled monitoring changes in the oxygenation level in the medulla after water loading, and may allow comparable feasibility to detect renal oxygenation level changes due to water loading compared with that of T2(*) mapping.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Third Affiliated Hospital of Suzhou University, Changzhou, Jiangsu 213003, China.

ABSTRACT

Objective: To assess the feasibility of susceptibility-weighted imaging (SWI) while monitoring changes in renal oxygenation level after water loading.

Materials and methods: Thirty-two volunteers (age, 28.0 ± 2.2 years) were enrolled in this study. SWI and multi-echo gradient echo sequence-based T2(*) mapping were used to cover the kidney before and after water loading. Cortical and medullary parameters were measured using small regions of interest, and their relative changes due to water loading were calculated based on baseline and post-water loading data. An intraclass correlation coefficient analysis was used to assess inter-observer reliability of each parameter. A receiver operating characteristic curve analysis was conducted to compare the performance of the two methods for detecting renal oxygenation changes due to water loading.

Results: Both medullary phase and medullary T2(*) values increased after water loading (p < 0.001), although poor correlations were found between the phase changes and the T2(*) changes (p > 0.05). Interobserver reliability was excellent for the T2(*) values, good for SWI cortical phase values, and moderate for the SWI medullary phase values. The area under receiver operating characteristic curve of the SWI medullary phase values was 0.85 and was not different from the medullary T2(*) value (0.84).

Conclusion: Susceptibility-weighted imaging enabled monitoring changes in the oxygenation level in the medulla after water loading, and may allow comparable feasibility to detect renal oxygenation level changes due to water loading compared with that of T2(*) mapping.

No MeSH data available.


Receiver operating characteristics curve analysis of two methods for detecting changes in renal oxygenation levels due to water loading.Area under receiver operating characteristic curve (AUC) was not significantly larger for medullary phase (φmedulla), as measured using susceptibility weighted imaging, than medullary T2* values (T2*medulla) using T2* map.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4499547&req=5

Figure 4: Receiver operating characteristics curve analysis of two methods for detecting changes in renal oxygenation levels due to water loading.Area under receiver operating characteristic curve (AUC) was not significantly larger for medullary phase (φmedulla), as measured using susceptibility weighted imaging, than medullary T2* values (T2*medulla) using T2* map.

Mentions: The AUC was 0.85 for φmedulla and 0.84 for T2*medulla (p = 0.85) (Fig. 4). Sensitivity and specificity were 87.50% and 71.87%, respectively when the φmedulla cutoffs was -9.99 × 10-3 rad, 75.00%, and 84.40% respectively when the T2*medulla cutoff was 26.22 ms.


Evaluation of Renal Oxygenation Level Changes after Water Loading Using Susceptibility-Weighted Imaging and T2* Mapping.

Ding J, Xing W, Wu D, Chen J, Pan L, Sun J, Xing S, Dai Y - Korean J Radiol (2015)

Receiver operating characteristics curve analysis of two methods for detecting changes in renal oxygenation levels due to water loading.Area under receiver operating characteristic curve (AUC) was not significantly larger for medullary phase (φmedulla), as measured using susceptibility weighted imaging, than medullary T2* values (T2*medulla) using T2* map.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4499547&req=5

Figure 4: Receiver operating characteristics curve analysis of two methods for detecting changes in renal oxygenation levels due to water loading.Area under receiver operating characteristic curve (AUC) was not significantly larger for medullary phase (φmedulla), as measured using susceptibility weighted imaging, than medullary T2* values (T2*medulla) using T2* map.
Mentions: The AUC was 0.85 for φmedulla and 0.84 for T2*medulla (p = 0.85) (Fig. 4). Sensitivity and specificity were 87.50% and 71.87%, respectively when the φmedulla cutoffs was -9.99 × 10-3 rad, 75.00%, and 84.40% respectively when the T2*medulla cutoff was 26.22 ms.

Bottom Line: Both medullary phase and medullary T2(*) values increased after water loading (p < 0.001), although poor correlations were found between the phase changes and the T2(*) changes (p > 0.05).The area under receiver operating characteristic curve of the SWI medullary phase values was 0.85 and was not different from the medullary T2(*) value (0.84).Susceptibility-weighted imaging enabled monitoring changes in the oxygenation level in the medulla after water loading, and may allow comparable feasibility to detect renal oxygenation level changes due to water loading compared with that of T2(*) mapping.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Third Affiliated Hospital of Suzhou University, Changzhou, Jiangsu 213003, China.

ABSTRACT

Objective: To assess the feasibility of susceptibility-weighted imaging (SWI) while monitoring changes in renal oxygenation level after water loading.

Materials and methods: Thirty-two volunteers (age, 28.0 ± 2.2 years) were enrolled in this study. SWI and multi-echo gradient echo sequence-based T2(*) mapping were used to cover the kidney before and after water loading. Cortical and medullary parameters were measured using small regions of interest, and their relative changes due to water loading were calculated based on baseline and post-water loading data. An intraclass correlation coefficient analysis was used to assess inter-observer reliability of each parameter. A receiver operating characteristic curve analysis was conducted to compare the performance of the two methods for detecting renal oxygenation changes due to water loading.

Results: Both medullary phase and medullary T2(*) values increased after water loading (p < 0.001), although poor correlations were found between the phase changes and the T2(*) changes (p > 0.05). Interobserver reliability was excellent for the T2(*) values, good for SWI cortical phase values, and moderate for the SWI medullary phase values. The area under receiver operating characteristic curve of the SWI medullary phase values was 0.85 and was not different from the medullary T2(*) value (0.84).

Conclusion: Susceptibility-weighted imaging enabled monitoring changes in the oxygenation level in the medulla after water loading, and may allow comparable feasibility to detect renal oxygenation level changes due to water loading compared with that of T2(*) mapping.

No MeSH data available.