Editor’s Choices
Apparent Diffusion Coefficient of Glial Neoplasms: Correlation with Fluorodeoxyglucose–Positron-Emission Tomography and Gadolinium-Enhanced MR Imaging • A.I. Holodny, S. Makeyev, B.J. Beattie, S. Riad, and R.G. Blasberg
The authors state that contrast enhancement does not always correlate with tumor histology and thus they compared the findings of FDG-PET and apparent diffusion coefficient maps to postcontrast MR images in 21 patients with cerebral glial neoplasias. All images were subjectively and objectively evaluated and correlation coefficients calculated for all regions of interest analyzed. Subjective evaluation showed a 60% correlation between PET and ADC with a greater overlap between PET and ADC than with contrast enhancement. ADC better correlated with survival (for more on this, listen to Dr. Cha’s podcast, April 2010). The authors concluded that ADC provided analogous information to PET when compared to gadolinium.
Simultaneous Bilateral Carotid Stenting in High-Risk Patients • S. Liu, J.H. Jung, S.-M. Kim, H.-K. Lim, H.-j. Kwon, J.K. Kim, J.S. Kim, and D.C. Suh
Here, the authors evaluated the results of bilateral carotid artery stenting in 30 consecutive patients. The procedure was simultaneous in 24 and staged in 6 patients. A group of 175 patients undergoing unilateral carotid stenting was used as controls. Outcomes at 30 days and 6 months were compared. Postprocedure hyperperfusion syndrome was more common after bilateral stenting, but there were no differences at 6 months between groups in minor or major strokes, re-stenosis, or death.
Similar Safety in Centers with Low and High Volumes of Endovascular Treatments for Unruptured Intracranial Aneurysms: Evaluation of the Analysis of Treatment by Endovascular Approach of Nonruptured Aneurysms Study • L. Pierot, L. Spelle, F. Vitry, for the ATENA Investigators
Do experienced interventionalists have better patient outcomes than those with lesser experience? These French authors selected 649 patients from the ATENA database and evaluated the results of aneurysm coilings in centers that had treated <20 aneurysms vs those centers that had treated >21 aneurysms. Stent-assisted procedures were performed more often in experienced centers, thromboembolic events and intraprocedural ruptures were more common in less experienced centers, but mortality and morbidity rates 1 month postprocedure as well as anatomic results were not different between the 2 groups of operators.
Fellows’ Journal Club
Diagnostic Yield of Double-Dose Gadobutrol in the Detection of Brain Metastasis: Intraindividual Comparison with Double-Dose Gadopentetate Dimeglumine • E.S. Kim, J.H. Chang, H.S. Choi, J. Kim, and S.-K. Lee
It seems that everything goes in circles! Many years ago we published a number of articles dealing with the benefits of double doses of MR imaging contrast agents. In a variation of the theme, these authors looked at the efficacy of double-dose gadobutrol vs double-dose gadopentetate dimeglumine in 27 patients who underwent gamma knife treatment of brain metastases. They counted the lesions and measured contrast-to-noise ratios. Gadobutrol was better, identifying 25 additional lesions and not missing any that were seen with gadopentetate. CNRs were also higher with gadobutrol. Because gadobutrol is safe in patients with renal impairment and has not been associated with systemic nephrogenic fibrosis, the authors concluded that double-dosing these specific patients is best.
Inter- and Intraobserver Agreement in CT Characterization of Nonaneurysmal Perimesencephalic Subarachnoid Hemorrhage • W. Brinjikji, D.F. Kallmes, J.B. White, G. Lanzino, J.M. Morris, and H.J Cloft
This is a topic of importance because the definition of perimesencephalic subarachnoid hemorrhage and its interpretation varies among individuals, and results in different work-ups. The authors retrospectively reviewed CT images in 37 patients with PM SAH in whom aneurysms had been excluded previously by digital subtraction angiography. In 78% of instances, the 4 readers agreed unanimously and they disagreed in 22% of cases. Intra- and interobserver agreements were considered good. Because there was disagreement, the authors suggest caution in interpreting this pattern of SAH and when deciding to pursue additional follow-up studies in such patients.
Dose Exposure of Patients Undergoing Comprehensive Stroke Imaging by Multidetector-Row CT: Comparison of 320-Detector Row and 64-Detector Row CT Scanners • S. Diekmann, E. Siebert, R. Juran, M. Roll, W. Deeg, H.-C. Bauknecht, F. Diekmann, R. Klingebiel, and G. Bohner
More CT detectors implies better coverage (with 320 detectors you can scan the entire brain) and higher quality studies, but these days we all are very concerned with radiation exposure. Using phantoms, exposures were measured for different body regions and effective doses were then calculated for the following different studies: head CT, CT angiography of the head and the neck, and CT perfusion. When compared to 64-detector CT, 320-detector CT delivered nearly 25% more radiation. Critical doses that would cause organ damage were not reached, but caution is advised and weighing risk vs benefit is important when using higher detector CT units.
