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Krisztina Fischer,1–3 Nathan J McDannold,1 Clare M Tempany,1 Ferenc A Jolesz,1,† Fiona M Fennessy1,4 1Department of Radiology, 2Renal Division, 3Biomedical Engineering Division, Brigham and Women’s Hospital, 4Department of Radiology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA †Ferenc A Jolesz passed away on December 31, 2014 Abstract: Minimally invasive treatment options are an important part of the uterine fibroid-treatment arsenal, especially among younger patients and in those who plan future pregnancies. This article provides an overview of the currently available minimally invasive therapy options, with a special emphasis on a completely noninvasive option: magnetic resonance-guided focused ultrasound (MRgFUS). In this review, we describe the background of MRgFUS, the patient-selection criteria for MRgFUS, and how the procedure is performed. We summarize the published clinical trial results, and review the literature on pregnancy post-MRgFUS and on the cost-effectiveness of MRgFUS. Keywords: uterine fibroids, MRgFUS, focused ultrasound, minimally invasive treatment&nbsp

Background Epilepsy is a common neurological disorder, which is attributed to uncontrollable abnormal hyper-excitability of neurons. We investigated the feasibility of using low-intensity, pulsed radiation of focused ultrasound (FUS) to non-invasively suppress epileptic activity in an animal model (rat), which was induced by the intraperitonial injection of pentylenetetrazol (PTZ). Results After the onset of induced seizures, FUS was transcranially administered to the brain twice for three minutes each while undergoing electroencephalographic (EEG) monitoring. An air-backed, spherical segment ultrasound transducer (diameter: 6 cm; radius-of-curvature: 7 cm) operating at a fundamental frequency of 690 KHz was used to deliver a train of 0.5 msec-long pulses of sonication at a repetitive rate of 100 Hz to the thalamic areas of the brain. The acoustic intensity (130 mW/cm2) used in the experiment was sufficiently within the range of safety guidelines for the clinical ultrasound imaging. The occurrence of epileptic EEG bursts from epilepsy-induced rats significantly decreased after sonication when it was compared to the pre-sonication epileptic state. The PTZ-induced control group that did not receive any sonication showed a sustained number of epileptic EEG signal bursts. The animals that underwent sonication also showed less severe epileptic behavior, as assessed by the Racine score. Histological analysis confirmed that the sonication did not cause any damage to the brain tissue. Conclusions These results revealed that low-intensity, pulsed FUS sonication suppressed the number of epileptic signal bursts using acute epilepsy model in animal. Due to its non-invasiveness and spatial selectivity, FUS may offer new perspectives for a possible non-invasive treatment of epilepsy.

Background Epilepsy is a common neurological disorder, which is attributed to uncontrollable abnormal hyper-excitability of neurons. We investigated the feasibility of using low-intensity, pulsed radiation of focused ultrasound (FUS) to non-invasively suppress epileptic activity in an animal model (rat), which was induced by the intraperitonial injection of pentylenetetrazol (PTZ). Results After the onset of induced seizures, FUS was transcranially administered to the brain twice for three minutes each while undergoing electroencephalographic (EEG) monitoring. An air-backed, spherical segment ultrasound transducer (diameter: 6 cm; radius-of-curvature: 7 cm) operating at a fundamental frequency of 690 KHz was used to deliver a train of 0.5 msec-long pulses of sonication at a repetitive rate of 100 Hz to the thalamic areas of the brain. The acoustic intensity (130 mW/cm2) used in the experiment was sufficiently within the range of safety guidelines for the clinical ultrasound imaging. The occurrence of epileptic EEG bursts from epilepsy-induced rats significantly decreased after sonication when it was compared to the pre-sonication epileptic state. The PTZ-induced control group that did not receive any sonication showed a sustained number of epileptic EEG signal bursts. The animals that underwent sonication also showed less severe epileptic behavior, as assessed by the Racine score. Histological analysis confirmed that the sonication did not cause any damage to the brain tissue. Conclusions These results revealed that low-intensity, pulsed FUS sonication suppressed the number of epileptic signal bursts using acute epilepsy model in animal. Due to its non-invasiveness and spatial selectivity, FUS may offer new perspectives for a possible non-invasive treatment of epilepsy.

The increased use of image-guided surgery systems during neurosurgery has brought to prominence the inaccuracies of conventional intraoperative navigation systems caused by shape changes such as those due to brain shift. We propose a method to track the deformation of the brain and update preoperative images using intraoperative MR images acquired at different crucial time points during surgery. We use a deformable surface matching algorithm to capture the deformation of boundaries of key structures (cortical surface, ventricles and tumor) throughout the neurosurgical procedure, and a linear finite element elastic model to infer a volumetric deformation. The boundary data are extracted from intraoperative MR images using a real-time intraoperative segmentation algorithm. The algorithm has been applied to a sequence of intraoperative MR images of the brain exhibiting brain shift and tumor resection. Our results characterize the brain shift after opening of the dura and at the different stages of tumor resection, and brain swelling afterwards. Analysis of the average deformation capture was assessed by comparing landmarks identified manually and the results indicate an accuracy of 0.7+/-0.6 mm (mean+/-S.D.) for boundary surface landmarks, of 0.9+/-0.6 mm for landmarks inside the boundary surfaces, and 1.6+/-0.9 mm for landmarks in the vicinity of the tumor.

Two studies were done using 3 iP magnetic resonance spectroscopy to examine the separate effects of hypohydration and dietary creatine supplementation on muscle metabolism and performance. Volunteers performed supine single-leg knee extension exercise in a 1.5 Tesla whole body magnetic resonance spectroscopy (MRS) system. For the hypohydration study, exercise was performed to exhaustion when euhydrated and 4% hypohydrated. Hypohydration reduced (P <0.05) time to fatigue 15% (EU =251+67 HY=213 +52 Sec; Isd). Muscle pH and Pi/BATP were similar during exercise and at exhaustion regardless of hydration state. It was concluded that hypohydration reduces muscle endurance and the effects appear independent of H + and Pi concentration. For the creatine studies, 3 repeat bouts of high-intensity exercise were performed before and after 5 days of creatine supplementation (0.3 g'kg-1-day-i). Middle-aged persons (5814 yr) had lower resting PCr/BATP compared to the young group (6.3610.94 vs. 7.18+0.93, p

Computer Tomography (CT) and Magnetic Resonance Imaging (MRI) are non-invasive diagnostic imaging modalities that display internal anatomy of the middle and inner ear as two-dimensional cross-sectional slices. Radiologists and otolaryngologists can view these 2-D images and usually create a mental model of the 3-D structures present in the study. However, many of the tubular structures that exist in the temporal bone have complex morphology and pass back and forth through the cross sections. Endoscopists view organs from the inside, but a navigationally and spatially constrained and, in the inner ear, real endoscopy is currently not possible. We demonstrate the use of 3-D computer graphics techniques to generate a non-invasive 'virtual' otoscopy of the middle and inner ear from CT or MRI data, that avoids the difficulties of traditional techniques and permits views of the middle and inner ear not otherwise attainable. If developed, virtual otoscopy will permit planning the treatment of a variety of inner ear pathologies without the need for ablative labyrinthectomy., Included with AD-M000 654.