Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY, United States.
Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY, United States; Biomedical Engineering and Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States.
Eur J Radiol. 2020 May;126:108931. doi: 10.1016/j.ejrad.2020.108931. Epub 2020 Mar 3.
Tumor consistency is a critical factor in surgical planning that influences ease of resection and risk of operative morbidity. The ability of MRI to predict tumor consistency tumor consistency has been shown to increase with higher field strength. The present study examined the utility of 7 T (7 T) MRI in predicting the tumor consistency of pituitary adenomas.
Fifteen patients with pituitary adenomas were preoperatively scanned at 7 T MRI. Regions of interest were drawn around lesions for voxel-based signal intensity (SI) analysis. The percentage of tumor voxels with intensity higher than local gray matter was calculated on T2-weighted imaging. A single neurosurgeon rated tumor firmness for all patients. Histopathological analysis was performed. Radiological tumor features were correlated with intraoperative tumor consistency measurements and histopathology.
Tumors rated as 'soft' intraoperatively were hyperintense to local gray matter on T2-weighted imaging. 'Firm' tumors were hypointense to local gray matter. There was no significant difference in SI ratio between soft and firm tumors (p = 0.098). Soft tumors had a significantly higher percentage of tumor voxels greater than local gray matter compared to firm tumors (p = 0.035, Cohen's D-effect size = 1.208). Soft tumors had higher vascularity than firm tumors, p = 0.015.
The signal and contrast advantage conferred by 7 T MRI may provide valuable preoperative information regarding pituitary tumor consistency and physiology. The use of granular, voxel-based analysis maximizes the potential afforded by the high resolution of 7 T imaging, and may be a valuable method of predicting consistency of pituitary adenoma.
肿瘤硬度是手术规划中的一个关键因素，它影响着切除的难易程度和手术发病率的风险。MRI 预测肿瘤硬度的能力随着磁场强度的增加而提高。本研究旨在检验 7T（7 特斯拉）MRI 在预测垂体腺瘤肿瘤硬度方面的作用。
15 例垂体腺瘤患者在术前接受 7T MRI 扫描。对病变进行感兴趣区勾画，进行基于体素的信号强度（SI）分析。在 T2 加权成像上计算肿瘤 SI 高于局部灰质的肿瘤体素百分比。由一位神经外科医生对所有患者的肿瘤硬度进行评分。对所有患者进行组织病理学分析。对影像学肿瘤特征与术中肿瘤硬度测量和组织病理学进行相关性分析。
术中评为“软”的肿瘤在 T2 加权成像上呈高信号，高于局部灰质。“硬”肿瘤的信号低于局部灰质。软肿瘤和硬肿瘤之间的 SI 比值没有显著差异（p=0.098）。与硬肿瘤相比，软肿瘤中大于局部灰质的肿瘤体素百分比明显更高（p=0.035，Cohen's D 效应量=1.208）。软肿瘤的血管生成比硬肿瘤高，p=0.015。
7T MRI 带来的信号和对比度优势，可能为垂体肿瘤硬度和生理学提供有价值的术前信息。基于体素的粒度分析最大限度地利用了 7T 成像的高分辨率，可能是预测垂体腺瘤硬度的一种有价值的方法。
