MR T2WI Research Articles

MRI diagnosis of sinonasal inverted papilloma

Objective To investigate the MRI findings of sinonasal inverted papilloma so as to promote the diagnostic accuracy.Methods All 36 cases of sinonasal inverted papilloma were verified by pathology.Their MRI findings were analyzed retrospectively.Results The lesion occurred in the lateral nasal wall in 25 cases,in the maxillary sinus in 4 cases,in the ethmoid sinus in 2 cases,in the frontal and ethmoid sinuses in 2 cases, in the ethmoid and sphenoid sinuses in 2 cases and in the frontal sinus in one case.Of the 36 cases,11 cases had recurrent lesions and 3 cases were associated with malignant change.All lesions showed well-defined margin,with lobulate configuration in 26 cases and irregular shape in 10 cases.The diameter of the lesions ranged from 22 to 82 mm (mean,38 mm).On MR T1WI,sinonasal inverted papilloma revealed isointense signal compared to adjacent muscle in 32 cases and slight hyperintense signal in 4.On T2 WI,the lesions showed heterogeneous hyperintense signal in 34 cases and inhomogeneous isointense signal in 2 cases with malignant change.Postcontrast MR imaging demonstrated marked inhomogeneous enhancement compared with nasal septum mucosa in 34 cases.Regular fence-like pattern was found on MR T2WI and enhanced T1WI in 32 cases,while irregular ones were found in three cases with malignant change.The time-intensity curve (TIC)of dynamic contrast enhancement of MRI showed rapid enhancing and slow wash-out type in 7 cases,while rapid enhancing and wash-out pattern was detected in one ease with malignant change.Conclusion Regular fence-like pattern on MR T2WI or enhanced T1WI was reliable characteristics for the diagnosis of sinonasal inverted papilloma.Irregular ones may suggest malignant change. Key words: Papilloma,inverted; Nasal cavity; Paranasal sinus discases; Magnetic resonance imaging

Asymptomatic carotid artery plaques: use of magnetic resonance imaging to characterize vulnerable plaques in 6 cases

Background Echography is a convenient and noninvasive method of characterizing carotid artery plaques. However, recent reports suggest that multisequential MR imaging may yield better data regarding the instability of asymptomatic carotid artery plaques. Therefore, the goal of the present study was to show the useful information for asymptomatic carotid artery plaque. Methods A total of 6 patients (5 men, 1 woman; age range, 62-76 years; mean age, 69.2 years) with carotid artery plaques, which were detected during medical check-up using carotid MR angiography and/or echography, underwent MR imaging. Two-dimensional TOF MR angiography, T1WI, and fat-suppressed, cardiac-gated, black-blood proton density image, and T2WI were obtained with a 1.5-T MR imager. All plaques underwent carotid endarterectomy and histological examination. Results The MR imaging demonstrated high signals in at least one modality in 4 of 7 plaques. In the remaining 3 patients, MR imaging detected partial-high signals, which corresponded to histologically confirmed partial lipid core or hemorrhagic components in the fibrous tissues The TOF MR imaging showed 2 cases of thin fibrous caps, and MR imaging also showed a large mural thrombus in 1 patient. Conclusions Magnetic resonance imaging was useful in characterizing factors associated with plaque instability in patients with asymptomatic carotid artery plaques and may help guide therapeutic strategies for asymptomatic carotid artery plaques.

Comparative studies of MRI and mammography in patients with breast diseases

目的 分析乳腺疾病的X线钼靶与MRI影像学表现,评价X线钼靶与MRI对乳腺疾病的诊断价值.方法回顾性分析了60例乳腺疾病的X线钼靶与MRI表现,MRI分别采用自旋回波T1WI、短时反转恢复(STIR)序列及动态增强扫描.X线钼靶采用常规方法摄片.结果MRI 53例诊断正确,与病理结果相符,MRI诊断的准确率为88.3%,X线钼靶38例诊断正确,与病理结果相符,X线钼靶诊断的准确率为63.3%,两者差异具有显著性意义,χ2=10.23,P＜0.01.结论MRI对乳腺疾病的诊断价值明显优于X线钼靶,对乳腺疾病的临床诊断及治疗具有重要意义。