Application of MRI diffusion weighted imaging and perfusion weighted in primary and secondary brain tumor evaluation

Purpose: The aim of this study was to evaluate the contribution of DWI and PWI in the clinical practice precisely: in characterization and grading of brain gliomas, characterization and differential diagnosis of brain malignancies, discrimination between benign and malignant brain lesions, characterization of meningioma (Μ) and discrimination between regression (R) and post irradiation necrosis (PIN). Patients and Methods: Conventional 1.5 T MRI, DWI, and PWI were performed on total of 185 patients. 170 patients with intracranial malignancies [low grade astrocytoma (LGA), high grade astrocytoma (HGA), solitary brain metastases (SBM) and brain lymphomas (BL), 124 patients with benign lesions [M, brain abscesses (BA), encephalitis (E), tumefactive multiple sclerosis (TMS), arteriovenous malformations (AVM) and PRES] and 15 patients with R, PIN or combination. Τhe diagnosis was confirmed for brain malignancies and for the cases with regression and PIN with strereotactic biopsy or resection (subtotal or total) and for benign brain lesions with strereotactic biopsy or resection or analysis of cerebrospinal fluid and laboratory examinations. The Mann-Whitney U test and One-Way ANOVA or Kruskal-Wallis employed in order to identify statistical differences in mean ADCs and mean rCBVs rations in the regions of interest of the brain lesions. Results: The mean ADCs in the solid part were lower in high-grade gliomas (HGG) than low grade gliomas (LGG), but not statistical significantly p> 0.001. The mean rCBVs in the solid part were higher in HGG than low LGG and statistical significantly, p 0.001. The mean rCBVs the solid part was higher in R than PIN with p0.001 και υψηλότερη τιμή λόγου rCBV με p<0.001.Συμπεράσματα: Η εφαρμογή των τεχνικών του μαγνητικού συντονισμού: DWI η οποία έμμεσα ανέδειξε την κυτταρική σύσταση της ΕΕ και PWI η οποία ανέδειξε την νεοαγγείωση, πρόσφερε σημαντικές πληροφορίες στον χαρακτηρισμό και την διάκριση των πρωτοπαθών και δευτεροπαθών εγκεφαλικών νεοπλασμάτων στην καθημερινή κλινική πράξη. Συγκεκριμένα επέτρεψαν την διάκριση μεταξύ ΧΚΑ από ΥΚΑ και συνέβαλαν στην βαθμονόμηση τους με την τεχνική της PWI και επικουρικά με την τεχνική της DWI. Και οι δύο τεχνικές συνέβαλλαν, στον χαρακτηρισμό της ΜΕΜ και στην διάκριση μεταξύ ΥΚΑ και ΜΕΜ, στον χαρακτηρισμό του ΕΛ και στην διαφορική διάγνωση του μεταξύ ΥΚΑ και ΜΕΜ. Η τεχνική της DWI, συνέβαλε στο χαρακτηρισμό του Μ και την διάκριση μεταξύ κυστικού τμήματος ΥΚΑ και ΕΑ. Τέλος PWI επέτρεψε την διάκριση μεταξύ Υ και ΜΙ

An atypical meningioma demystified and advanced magnetic resonance imaging techniques

A 40-year-old male presented with visuospatial processing disturbances. Family history was free. Conventional and advanced magnetic resonance imaging (MRI) studies were performed. On T2 and fluid attenuation inversion recovery images, an increased signal intensity extra-axial lesion was demonstrated. Post-contrast scans depicted homogeneous intense contrast medium enhancement. T2FNx01 star sequence was negative for hemorrhagic or calcification foci. Diffusion-weighted imaging findings were indicative of malignant behavior and magnetic resonance venography confirmed superior sagittal sinus infiltration. Increased cerebral blood volume values were observed and peri-lesional oedema on perfusion-weighted imaging was also demonstrated. The signal intensity-time curve depicted the characteristic meningioma pattern. Spectroscopy showed increased choline and alanine levels, but decreased N-acetyl-aspartate levels. Conventional MRI is adequate for typical types of meningiomas. However, the more atypical ones, in which even the histopathologic specimen may demonstrate characteristics of typical meningioma, could be easier diagnosed with advanced MRI techniques

An atypical meningioma demystified and advanced magnetic resonance imaging techniques

A 40-year-old male presented with visuospatial processing disturbances. Family history was free. Conventional and advanced magnetic resonance imaging (MRI) studies were performed. On T2 and fluid attenuation inversion recovery images, an increased signal intensity extra-axial lesion was demonstrated. Post-contrast scans depicted homogeneous intense contrast medium enhancement. T2FNx01 star sequence was negative for hemorrhagic or calcification foci. Diffusion-weighted imaging findings were indicative of malignant behavior and magnetic resonance venography confirmed superior sagittal sinus infiltration. Increased cerebral blood volume values were observed and peri-lesional oedema on perfusion-weighted imaging was also demonstrated. The signal intensity-time curve depicted the characteristic meningioma pattern. Spectroscopy showed increased choline and alanine levels, but decreased N-acetyl-aspartate levels. Conventional MRI is adequate for typical types of meningiomas. However, the more atypical ones, in which even the histopathologic specimen may demonstrate characteristics of typical meningioma, could be easier diagnosed with advanced MRI techniques