The Quantification of the Iron Contents in the Ovarian Endometrial Cyst; R2 Measurement in Vivo and Vitro

Junko Takahama¹, Hiroshi Kobayashi², Chiharu Yoshimoto², Hiroshi Shigetomi², Masato Uchikoshi³, Takuya Iwabuchi⁴, Nagaaki Marugami¹, and Kimihiko Kichikawa¹

¹Radiology, Nara Medical University, Kashihara, Japan, ²Gynecology, Nara Medical University, Kashihara, Japan, ³Siemens AG, Erlangen, Germany, ⁴Metallogenics Co., Ltd., Chiba, Japan

Synopsis

The measurement of R2 values to quantify the iron concentration in vivo and vitro.

Purpose

The ovarian endometrial cysts, known as popular female pelvic benign lesions, are also the precursor of ovarian cancer. The carcinogenesis in endometrial cysts was reported to correlate with the free radical caused by the iron ion of the hemorrhagic cystic contents. The iron quantification in the endometriosis can be the clue to predict the ovarian cancer arising from endometriosis. The purpose of this study is to evaluate the iron quantification in vivo using R2 value obtained by multi echo T2 corrected single voxel spectroscopy.

Materials and Methods

To evaluate the R2 of endometrial cyst in vivo, we performed MRI (3T, Verio, Siemens) in both pre-operation (in vivo) and evacuated content (in vitro). The Multi Echo T2 corrected Single Voxel Spectroscopy was applied by Siemens to measure the R2.2 The R2 value was compared with the iron density measured by biochemical analysis (inductively coupled plasma optical emission spectrometry). To clarify the iron ion affect to R2 value, we also evaluate the phantom of the fluid, Fe with Hemoglobin in multiple densities in vitro. The 6 patients with 8 endometrial cysts were evaluated. MRI was performed the day before the operation, and the voxel (sized 1.5x1.5x1.5cm) was located by the well-trained radiologist(Figure 1). After the operation, the contents of cysts were evaluated by MRI in the same way using the tube phantom fixed with agar. The iron density of the cystic fluid was also analyzed by biochemical analysis. Using the same phantoms, that the 6 tubes fixed with agar box, we measured R2 of the fluid, Fe with albumin in water (0, 1, 5, 10, 25, 50(mg/l)).

Results

The R2 value in vivo and vitro evaluated by Multi Echo T2 corrected Single Voxel Spectroscopy was shown in table 1. The correlation coefficient of R2 between in vivo and vitro was r=0.929 (Fig.2a). The iron density and R2 in vivo and in vitro was also had a good correlation (r=0.946, R=0.926)(Fig 2b, c). For the phantom study, the Fe density with albumin in water and R2 was shown in table 2 and had a good correlation (Table 3, Fig. 3).

Conclusion

The R2 value evaluated by MRI using Multi Echo T2 corrected Single Voxel Spectroscopy correlate the iron density in ovarian endometrial cyst.

Acknowledgements

No acknowledgement found.

References

1. Yamaguchi K, Mandai M, Toyokuni S, Hamanishi J, Higuchi T, Takakura K, Fujii S. Contents of endometriotic cysts, especially the high concentration of free iron, are a possible cause of carcinogenesis in the cysts through the iron-induced persistent oxidative stress. Clin Cancer Res. 2008 Jan 1;14(1):32-40. 2. Pineda N, Sharma P, Xu Q, Hu X, Vos M, Martin DR. Measurement of Hepatic Lipid: High-Speed T2-Corrected Multiecho Acquisition at 1 H MR Spectroscopy—A Rapid and Accurate Technique 1. Radiology. 2009 Aug;252(2):568–76.

Figures

Figure 1 The single voxel spectroscopy; the located VOI

R2 value of the endometrial cyst in vivo and vitro correlated with Fe density

Figure 2a, b, c

The correlation coefficient of R2 between in vivo and vitro was r=0.929 (Fig.2a). The iron density and R2 in vivo and in vitro was also had a good correlation (r=0.946, R=0.926)(Fig 2b, c).

Table 2 and Figure 3 The phantom study of the fluid with Fe with albmin: the density of Fe and the R2 value

Proc. Intl. Soc. Mag. Reson. Med. 24 (2016)

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