Abstract
Amirah Alsaedi1,2, Fabio Doniselli3,4, Hans Rolf Jäger2,5, Jasmina Panovska-Griffiths6, Antonio Rojas-Garcia6, Xavier Golay2 and Sotirios Bisdas2,5
1Department of Radiology Technology, Taibah University, Medina, KSA
2Department of Brain Repair & Rehabilitation, Queen Square Institute of Neurology, University College London, London, UK
3Postgraduate School in Radiodiagnostics, Università degli Studi di Milano, Milan, Italy
4PhD Course in Clinical Research, Università degli Studi di Milano, Milan, Italy
5Lysholm Department of Neuroradiology, The National Hospital for Neurology and Neurosurgery, University College Hospitals NHS Trust, London, UK
6Department of Applied Health Research, University College London, London, UK
Correspondence to:
Amirah Alsaedi, email: amirah.alsaedi.13@ucl.ac.uk
Keywords: glioma; arterial spin labeling; grading
Received: October 30, 2018 Accepted: February 01, 2019 Published: February 22, 2019
ABSTRACT
This study aimed to evaluate the diagnostic performance of arterial spin labelling (ASL) in grading of adult gliomas. Eighteen studies matched the inclusion criteria and were included after systematic searches through EMBASE and MEDLINE databases. The quality of the included studies was assessed utilizing Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). The quantitative values were extracted and a meta-analysis was subsequently based on a random-effect model with forest plot and joint sensitivity and specificity modelling. Hierarchical summary receiver operating characteristic (HROC) curve analysis was also conducted. The absolute tumour blood flow (TBF) values can differentiate high-grade gliomas (HGGs) from low-grade gliomas (LGGs) and grade II from grade IV tumours. However, it lacked the capacity to differentiate grade II from grade III tumours and grade III from grade IV tumours. In contrast, the relative TBF (rTBF) is effective in differentiating HGG from LGG and in glioma grading. The maximum rTBF (rTBFmax) demonstrated the best results in glioma grading. These results were also reflected in the sensitivity/ specificity analysis in which the rTBFmax showed the highest discrimination performance in glioma grading. The estimated effect size for the rTBF was approximately similar between HGGs and LGGs, and grade II and grade III tumours, (–1.46 (–2.00, –0.91), p- value < 0.001), (–1.39 (–1.89, –0.89), p- value < 0.001), respectively; while it exhibited smaller effect size between grade III and grade IV (–1.05 (–1.82, –0.27)), p < 0.05). Sensitivity and specificity analysis replicate these results as well. This meta-analysis suggests that ASL is useful for glioma grading, especially when considering the rTBFmax parameter.