Publications by Year: 2016

Torcuator RG, Hulou MM, Chavakula V, Jolesz FA, Golby AJ. Intraoperative Real-time MRI-guided Stereotactic Biopsy Followed by Laser Thermal Ablation for Progressive Brain Metastases after Radiosurgery. J Clin Neurosci. 2016;24 :68-73.Abstract

Stereotactic radiosurgery is one of the treatment options for brain metastases. However, there are patients who will progress after radiosurgery. One of the potential treatments for this subset of patients is laser ablation. Image-guided stereotactic biopsy is important to determine the histopathological nature of the lesion. However, this is usually based on preoperative, static images, which may affect the target accuracy during the actual procedure as a result of brain shift. We therefore performed real-time intraoperative MRI-guided stereotactic aspiration and biopsies on two patients with symptomatic, progressive lesions after radiosurgery followed immediately by laser ablation. The patients tolerated the procedure well with no new neurologic deficits. Intraoperative MRI-guided stereotactic biopsy followed by laser ablation is safe and accurate, providing real-time updates and feedback during the procedure.

Mitsouras D, Mulkern RV, Maier SE. Multicomponent T2 Relaxation Studies of the Avian Egg. Magn Reson Med. 2016;75 (5) :2156-64.Abstract

PURPOSE: To investigate the tissue-like multiexponential T2 signal decays in avian eggs. METHODS: Transverse relaxation studies of raw, soft-boiled and hard-boiled eggs were performed at 3 Tesla using a three-dimensional Carr-Purcell-Meiboom-Gill imaging sequence. Signal decays over a TE range of 11 to 354 ms were fitted assuming single- and multicomponent signal decays with up to three separately decaying components. Fat saturation was used to facilitate spectral assignment of observed decay components. RESULTS: Egg white, yolk and the centrally located latebra all demonstrate nonmonoexponential T2 decays. Specifically, egg white exhibits two-component decays with intermediate and long T2 times. Meanwhile, yolk and latebra are generally best characterized with triexponential decays, with short, intermediate and very long T2 decay times. Fat saturation revealed that the intermediate component of yolk could be attributed to lipids. Cooking of the egg profoundly altered the decay curves. CONCLUSION: Avian egg T2 decay curves cover a wide range of decay times. Observed T2 components in yolk and latebra as short as 10 ms, may prove valuable for testing clinical sequences designed to measure short T2 components, such as myelin-associated water in the brain. Thus we propose that the egg can be a versatile and widely available MR transverse relaxation phantom. Magn Reson Med 75:2156-2164, 2016. © 2015 Wiley Periodicals, Inc.