More articles from ADULT BRAIN
- Whole-Tumor Histogram and Texture Analyses of DTI for Evaluation of IDH1-Mutation and 1p/19q-Codeletion Status in World Health Organization Grade II Gliomas
Ninety-three patients with World Health Organization grade II gliomas with known IDH-mutation and 1p/19q-codeletion status (18 IDH1 wild-type, 45 IDH1-mutant and no 1p/19q codeletion, 30 IDH-mutant and 1p/19q codeleted tumors) underwent DTI. ROIs were drawn on every section of the T2-weighted images and transferred to the ADC and the fractional anisotropy maps to derive volume-based data of the entire tumor. Histogram and texture analyses were correlated with the IDH1-mutation and 1p/19q-codeletion status. Various histogram and texture parameters differed significantly according to IDH1-mutation and 1p/19q-codeletion status. The skewness and energy of ADC, fractional anisotropy 10th and 25th percentiles, and correlation of fractional anisotropy were independent predictors of an IDH1 wild-type in the least absolute shrinkage and selection operator. The authors conclude that whole-tumor histogram and texture features of the ADC and fractional anisotropy maps are useful for predicting the IDH1-mutation and 1p/19q-codeletion status in World Health Organization grade II gliomas.
- HARMless: Transient Cortical and Sulcal Hyperintensity on Gadolinium-Enhanced FLAIR after Elective Endovascular Coiling of Intracranial Aneurysms
The authorsconducted a retrospective review of 58 patients with 62 MR imaging studies performed within 72 hours following endovascular treatment of intracranial aneurysms. Patient demographics, aneurysm location, and vascular territory distribution of cortical and sulcalhyperintensity on gadolinium-enhanced FLAIR were documented. Cortical and sulcalhyperintensity on gadolinium-enhanced FLAIR was found in 51.61% of post-endovascular treatment MR imaging studies, with complete resolution of findings in all patients on the available follow-up studies (27/27). Angiographic iodinated contrast medium injection and arterial anatomy matched the vascular distribution of cortical and sulcalhyperintensity on gadolinium-enhanced FLAIR. Thishyperintensity is a transient observation in the arterial territory exposed to iodinated contrast medium during endovascular treatment of intracranial aneurysms, and is significantly associated with procedural time and the frequency of angiographic runs, suggesting a potential technical influence on the breakdown of the BBB.
- Quantification of Intracranial Aneurysm Volume Pulsation with 7T MRI
Tenunruptured aneurysms in 9 patients were studied using a high-resolution 3D gradient-echo sequence with cardiac gating. Semiautomatic segmentation was used to measure aneurysm volume per cardiac phase. Aneurysm pulsation was defined as the relative increase in volume between the phase with the smallest volume and the phase with the largest volume. The accuracy and precision of the measured volume pulsations were addressed by digital phantom simulations and a repeat image analysis. In Stage II, the imaging protocol was optimized and 9 patients with 9 aneurysms were studied with and without administration of a contrast agent. Mean aneurysm pulsation in Stage I was 8%, with a mean volume change of 15 mm3. The artifactual volume pulsations measured with the digital phantom simulations were of the same magnitude as the volume pulsations observed in the patient data. Volume pulsation quantification with the current imaging protocol on 7T MR imaging is not accurate due to multiple imaging artifacts.