Groupe Hospitalier Pitié-Salpêtrière, Neuroradiology department, AP-HP, 47-83 bd de l'Hôpital, 75651, Paris, France.
Radiology department, Ghent University Hospital, Ghent, Belgium.
Clin Neuroradiol. 2019 Mar;29(1):75-86. doi: 10.1007/s00062-017-0623-7. Epub 2017 Sep 11.
Pseudo-continuous arterial spin labeling (pCASL) is a non-invasive magnetic resonance (MR) perfusion technique. Our study aimed at estimating the diagnostic performance of the pCASL sequence in assessing the perfusion of skull base lesions both qualitatively and quantitatively and at providing cut-off values for differentiation of specific skull base lesions.
In this study 99 patients with histopathologically confirmed skull base lesions were retrospectively enrolled. Based on a pathological analysis, the lesions were classified as hypervascular and non-hypervascular. Patients were divided into two subgroups according to the anatomical origin of each lesion. The MRI study included pCASL and 3D T1-weighted fat-saturated post-contrast sequences. Of the patients seven were excluded due to technical difficulties or patient movement. The lesions were classified by two raters, blinded to the diagnosis as either hyperperfused or non-hyperperfused, based on the pCASL sequence. The normalized tumor blood flow (nTBF) of each lesion was determined. Qualitative and quantitative characteristics of hypervascular and non-hypervascular lesions were compared.
Visual assessment enabled correct classification of 98% of the lesions to be performed. Quantitatively, we found significant differences between the nTBF values for hypervascular and non-hypervascular lesions (p < 0.001) and provided cut-off values, allowing meningioma and schwannoma to be distinguished from meningioma and adenoma. Significant differences were also found within the hypervascular group, namely, paraganglioma was more hyperperfused than meningioma (p = 0.003) or metastases (p = 0.009).
The present study demonstrates the high diagnostic performance of pCASL in characterizing skull base lesions by either visual assessment or nTBF quantification. Adding the pCASL sequence to the conventional protocol of skull base assessment can be recommended.
伪连续动脉自旋标记（pCASL）是一种非侵入性磁共振（MR）灌注技术。我们的研究旨在评估 pCASL 序列在定性和定量评估颅底病变灌注方面的诊断性能，并提供区分特定颅底病变的截止值。
本研究回顾性纳入了 99 例经组织病理学证实的颅底病变患者。根据病理分析，将病变分为高血管性和非高血管性。根据病变的解剖起源，将患者分为两组。MRI 研究包括 pCASL 和 3D T1 加权脂肪饱和对比后序列。由于技术困难或患者移动，有 7 例患者被排除在外。根据 pCASL 序列，两位阅片者将病变分为高灌注或非高灌注，对病变进行分类。确定每个病变的归一化肿瘤血流（nTBF）。比较高血管性和非高血管性病变的定性和定量特征。
视觉评估能够正确分类 98%的病变。定量分析发现，高血管性和非高血管性病变的 nTBF 值存在显著差异（p<0.001），并提供了截止值，允许区分脑膜瘤和神经鞘瘤与脑膜瘤和腺瘤。在高血管性病变组内也发现了显著差异，即副神经节瘤比脑膜瘤（p=0.003）或转移瘤（p=0.009）更灌注。
本研究表明，pCASL 无论是通过视觉评估还是 nTBF 定量都能很好地诊断颅底病变。建议在颅底评估的常规方案中加入 pCASL 序列。
