1. Non-echoplanar diffusion weighed imaging and T1-weighted imaging for cholesteatoma mastoid extension.
- Author
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Baba, Akira, Kurihara, Sho, Fukuda, Takeshi, Yamauchi, Hideomi, Matsushima, Satoshi, Ikeda, Koshi, Kurokawa, Ryo, Ota, Yoshiaki, Takahashi, Masahiro, Sakurai, Yuika, Motegi, Masaomi, Komori, Manabu, Yamamoto, Kazuhisa, Yamamoto, Yutaka, Kojima, Hiromi, and Ojiri, Hiroya
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MASTOIDECTOMY , *MAGNETIC resonance imaging , *CHOLESTEATOMA , *DIFFUSION magnetic resonance imaging , *MIDDLE ear , *ENDOSCOPIC surgery , *MASTOID process surgery , *EAR surgery , *MASTOID process , *ENDOSCOPY - Abstract
Objectives: A broad mastoid extension limits cholesteatoma resection via a transmeatal approach including endoscopic ear surgery. Therefore, a preoperative diagnosis of mastoid extension is a the most critical factor to determine whether to perform mastoidectomy. The purpose of this study was to assess the efficacy of non-echoplanar diffusion-weighted imaging (non-EPI DWI) and T1-weighted imaging in the evaluation of mastoid extension in cholesteatomas of the middle ear.Methods: Patients who underwent magnetic resonance imaging (MRI) for pretreatment evaluation before primary surgery for pars flaccida or tensa cholesteatoma, which revealed a high-signal intensity in the mastoid on T2-weighed imaging were retrospectively evaluated. Two board-certified radiologists retrospectively evaluated the extent of cholesteatomas on MRI with non-EPI DWI, non-EPI DWI- and T1-weighted axial imaging. The presence of a high signal intensity on non-EPI DWI or low or high signal intensity on T1-weighted imaging in the mastoid was evaluated. All cases were subclassified as M+ (surgically mastoid extension-positive) or M- (surgically mastoid extension-negative).Results: A total of 59 patients with middle ear cholesteatoma were evaluated. There were 37 M+ cases and 22 M- cases. High-signal intensity on non-EPI DWI exhibited a sensitivity of 0.89 and specificity of 0.82, whereas partial low-signal intensity on T1-weighted imaging exhibited a sensitivity of 0.84 and specificity of 0.91 for detecting mastoid involvement. Complete high-signal intensity on T1-weighted imaging exhibited a sensitivity of 0.73 and specificity of 0.89 for detecting non-involvement of the mastoid. The sensitivity (0.92) and specificity (0.96) of combined non-EPI DWI and T1-weighted imaging evaluation were higher than those of with non-EPI DWI or T1-weighted imaging alone. The interobserver agreement for the presence of high-signal intensity in the mastoid cavity on non-EPI DWI was very good at 0.82, that of a partial low-signal intensity area in the mastoid cavity lesions on T1-weighted imaging was good, at 0.76 and that of complete high-signal intensity in the mastoid cavity lesions on T1-weighted imaging was good, at 0.67.Conclusions: The signal intensity on non-EPI DWI and T1-weighted imaging of the mastoid could be used to accurately assess the extent of middle ear cholesteatoma, which could facilitate surgical treatment planning. [ABSTRACT FROM AUTHOR]- Published
- 2021
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