51
|
Klooster DCW, de Louw AJA, Aldenkamp AP, Besseling RMH, Mestrom RMC, Carrette S, Zinger S, Bergmans JWM, Mess WH, Vonck K, Carrette E, Breuer LEM, Bernas A, Tijhuis AG, Boon P. Technical aspects of neurostimulation: Focus on equipment, electric field modeling, and stimulation protocols. Neurosci Biobehav Rev 2016; 65:113-41. [PMID: 27021215 DOI: 10.1016/j.neubiorev.2016.02.016] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 02/05/2016] [Accepted: 02/17/2016] [Indexed: 12/31/2022]
Abstract
Neuromodulation is a field of science, medicine, and bioengineering that encompasses implantable and non-implantable technologies for the purpose of improving quality of life and functioning of humans. Brain neuromodulation involves different neurostimulation techniques: transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), vagus nerve stimulation (VNS), and deep brain stimulation (DBS), which are being used both to study their effects on cognitive brain functions and to treat neuropsychiatric disorders. The mechanisms of action of neurostimulation remain incompletely understood. Insight into the technical basis of neurostimulation might be a first step towards a more profound understanding of these mechanisms, which might lead to improved clinical outcome and therapeutic potential. This review provides an overview of the technical basis of neurostimulation focusing on the equipment, the present understanding of induced electric fields, and the stimulation protocols. The review is written from a technical perspective aimed at supporting the use of neurostimulation in clinical practice.
Collapse
Affiliation(s)
- D C W Klooster
- Kempenhaeghe Academic Center for Epileptology, P.O. Box 61, 5590 AB Heeze, The Netherlands; Department of Electrical Engineering, University of Technology Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
| | - A J A de Louw
- Kempenhaeghe Academic Center for Epileptology, P.O. Box 61, 5590 AB Heeze, The Netherlands; Department of Electrical Engineering, University of Technology Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands; Department of Neurology, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ Maastricht, The Netherlands.
| | - A P Aldenkamp
- Kempenhaeghe Academic Center for Epileptology, P.O. Box 61, 5590 AB Heeze, The Netherlands; Department of Electrical Engineering, University of Technology Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands; Department of Neurology, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ Maastricht, The Netherlands; School for Mental Health and Neuroscience, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands; Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
| | - R M H Besseling
- Department of Electrical Engineering, University of Technology Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
| | - R M C Mestrom
- Department of Electrical Engineering, University of Technology Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
| | - S Carrette
- Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
| | - S Zinger
- Kempenhaeghe Academic Center for Epileptology, P.O. Box 61, 5590 AB Heeze, The Netherlands; Department of Electrical Engineering, University of Technology Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
| | - J W M Bergmans
- Department of Electrical Engineering, University of Technology Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
| | - W H Mess
- Departments of Clinical Neurophysiology, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ Maastricht, The Netherlands.
| | - K Vonck
- Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
| | - E Carrette
- Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
| | - L E M Breuer
- Kempenhaeghe Academic Center for Epileptology, P.O. Box 61, 5590 AB Heeze, The Netherlands.
| | - A Bernas
- Department of Electrical Engineering, University of Technology Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
| | - A G Tijhuis
- Department of Electrical Engineering, University of Technology Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
| | - P Boon
- Kempenhaeghe Academic Center for Epileptology, P.O. Box 61, 5590 AB Heeze, The Netherlands; Department of Electrical Engineering, University of Technology Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands; Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
| |
Collapse
|
52
|
Bredlau AL, McCrackin MA, Motamarry A, Helke K, Chen C, Broome AM, Haemmerich D. Thermal Therapy Approaches for Treatment of Brain Tumors in Animals and Humans. Crit Rev Biomed Eng 2016; 44:443-457. [PMID: 29431091 DOI: 10.1615/critrevbiomedeng.2017021249] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Primary brain tumors are often aggressive, with short survival from time of diagnosis even with standard of care therapies such as surgery, chemotherapy, and radiation therapy. Thermal therapies have been extensively investigated as both primary and adjuvant therapy. Although thermal therapies are not yet widely used clinically, there have been several promising approaches demonstrated in both animals and humans. This review presents thermal therapy approaches in animal and human studies, including both hyperthermia (temperatures ~42°C-45°C) and thermal ablation (temperatures > 50°C). Hyperthermia is primarily used as adjuvant to chemotherapy and radiotherapy, and is the most widely studied radiation sensitizer where enhanced efficacy has been shown in human patients with brain cancer. Hyperthermia has additional beneficial effects such as immunogenic effects, and opening of the bloodbrain barrier to potentially enhance drug delivery, for example in combination with nanoparticle drug delivery systems. Thermal ablation uses high temperatures for direct local tumor destruction, and it found its way into clinical use as laser interstitial thermal therapy (LITT). This review presents various hyperthermia and ablation approaches, including a review of different devices and methods that have been used for thermal therapies, such as radiofrequency/microwaves, laser, high-intensity focused ultrasound, and magnetic nanoparticles. Current research efforts include the combination of advanced thermal therapy devices, such as focused ultrasound with radiation, as well as the use of thermal therapies to enhance chemotherapy delivery across the blood-brain barrier.
Collapse
Affiliation(s)
- A L Bredlau
- Departments of Pediatrics and Neurosciences, Medical University of South Carolina, Charleston, South Carolina
| | - M A McCrackin
- Department of Comparative Medicine, Medical University of South Carolina; Ralph H. Johnson VAMC Research Service, Charleston, South Carolina
| | - Anjan Motamarry
- Department of Pediatrics, Medical University of South Carolina, Charleston, South Carolina
| | - Kris Helke
- Ralph H. Johnson VAMC Research Service, Charleston, South Carolina
| | - Chao Chen
- Department of Cell and Molecular Pharmacology & Experimental Therapeutics, Medical University of South Carolina, Charleston, South Carolina
| | - Ann-Marie Broome
- Department of Cell and Molecular Pharmacology & Experimental Therapeutics, Medical University of South Carolina, Charleston, South Carolina
| | - Dieter Haemmerich
- Department of Pediatrics, Medical University of South Carolina, Charleston, South Carolina, USA; Department of Bioengineering, Clemson University, Clemson, South Carolina, USA
| |
Collapse
|
53
|
Gray JP, Dana N, Dextraze KL, Maier F, Emelianov S, Bouchard RR. Multi-Wavelength Photoacoustic Visualization of High Intensity Focused Ultrasound Lesions. ULTRASONIC IMAGING 2015; 38:96-112. [PMID: 26149314 DOI: 10.1177/0161734615593747] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
High intensity focused ultrasound (HIFU) thermal therapies are limited by deficiencies in existing image-guidance techniques. Previous studies using single-wavelength photoacoustic (PA) imaging have demonstrated that HIFU lesions generate contrast with respect to native tissues but have not sufficiently assessed lesion extent. The purpose of this study is to demonstrate feasibility of characterization of in vitro HIFU ablation lesion dimensions using 3D multi-wavelength PA imaging. Fresh porcine cardiac and liver tissue samples were embedded in agar phantoms and ablated using a 2.5 MHz small-animal HIFU system. Both 2D and 3D multi-wavelength photoacoustic-ultrasonic (PAUS) scans were performed in the near-infrared (NIR) range to characterize the change in the absorption spectrum of tissues following ablation and were compared to stained gross pathology to assess treatment margins and lesion extent. Comprehensive 2D multi-wavelength PA imaging yielded a spectrum in ablated tissue that did not display the characteristic local maximum in the optical absorption spectrum of deoxy-hemoglobin (Hb) near 760 nm. Two-dimensional tissue characterization map (TCM) images reconstructed from 3D TCM volumes reliably characterized lesion area and showed >70% area agreement with stained gross pathology. In addition, tissue samples were heated via water bath and concurrently interrogated with 2D PAUS imaging. PA signal exhibited an initial amplitude increase across all wavelengths, corresponding to an initial temperature increase, before then exhibiting a spectral change. This study suggests that multi-wavelength PA imaging has potential to obtain accurate characterization of HIFU lesion extent and may be better suited to guide HIFU ablation therapies during clinical treatments than single-wavelength methods.
Collapse
Affiliation(s)
- J P Gray
- MD Anderson Cancer Center, Houston, TX, USA
| | - N Dana
- University of Texas at Austin, Austin, TX, USA
| | | | - F Maier
- MD Anderson Cancer Center, Houston, TX, USA
| | - S Emelianov
- University of Texas at Austin, Austin, TX, USA
| | | |
Collapse
|
54
|
Chang WS, Jung HH, Kweon EJ, Zadicario E, Rachmilevitch I, Chang JW. Unilateral magnetic resonance guided focused ultrasound thalamotomy for essential tremor: practices and clinicoradiological outcomes. J Neurol Neurosurg Psychiatry 2015; 86:257-64. [PMID: 24876191 DOI: 10.1136/jnnp-2014-307642] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Several options exist for surgical management of essential tremor (ET), including radiofrequency lesioning, deep brain stimulation and γ knife radiosurgery of the ventralis intermedius nucleus of the thalamus. Recently, magnetic resonance-guided focused ultrasound (MRgFUS) has been developed as a less-invasive surgical tool aimed to precisely generate focal thermal lesions in the brain. METHODS Patients underwent tremor evaluation and neuroimaging study at baseline and up to 6 months after MRgFUS. Tremor severity and functional impairment were assessed at baseline and then at 1 week, 1 month, 3 months and 6 months after treatment. Adverse effects were also sought and ascertained by directed questions, neuroimaging results and neurological examination. RESULTS The current feasibility study attempted MRgFUS thalamotomy in 11 patients with medication-resistant ET. Among them, eight patients completed treatment with MRgFUS, whereas three patients could not complete the treatment because of insufficient temperature. All patients who completed treatment with MRgFUS showed immediate and sustained improvements in tremors lasting for the 6-month follow-up period. Skull volume and maximum temperature rise were linearly correlated (linear regression, p=0.003). Other than one patient who had mild and delayed postoperative balance, no patient developed significant postsurgical complications; about half of the patients had bouts of dizziness during the MRgFUS. CONCLUSIONS Our results demonstrate that MRgFUS thalamotomy is a safe, effective and less-invasive surgical method for treating medication-refractory ET. However, several issues must be resolved before clinical application of MRgFUS, including optimal patient selection and management of patients during treatment.
Collapse
Affiliation(s)
- Won Seok Chang
- Department of Neurosurgery, Brain Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Hyun Ho Jung
- Department of Neurosurgery, Brain Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Eun Jung Kweon
- Department of Neurosurgery, Brain Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | | | | | - Jin Woo Chang
- Department of Neurosurgery, Brain Research Institute, Yonsei University College of Medicine, Seoul, Korea
| |
Collapse
|
55
|
Coluccia D, Fandino J, Schwyzer L, O'Gorman R, Remonda L, Anon J, Martin E, Werner B. First noninvasive thermal ablation of a brain tumor with MR-guided focused ultrasound. J Ther Ultrasound 2014; 2:17. [PMID: 25671132 PMCID: PMC4322509 DOI: 10.1186/2050-5736-2-17] [Citation(s) in RCA: 149] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Accepted: 08/27/2014] [Indexed: 11/21/2022] Open
Abstract
Magnetic resonance-guided focused ultrasound surgery (MRgFUS) allows for precise
thermal ablation of target tissues. While this emerging modality is increasingly
used for the treatment of various types of extracranial soft tissue tumors, it
has only recently been acknowledged as a modality for noninvasive neurosurgery.
MRgFUS has been particularly successful for functional neurosurgery, whereas its
clinical application for tumor neurosurgery has been delayed for various
technical and procedural reasons. Here, we report the case of a 63-year-old
patient presenting with a centrally located recurrent glioblastoma who was
included in our ongoing clinical phase I study aimed at evaluating the
feasibility and safety of transcranial MRgFUS for brain tumor ablation. Applying
25 high-power sonications under MR imaging guidance, partial tumor ablation
could be achieved without provoking neurological deficits or other adverse
effects in the patient. This proves, for the first time, the feasibility of
using transcranial MR-guided focused ultrasound to safely ablate substantial
volumes of brain tumor tissue.
Collapse
Affiliation(s)
- Daniel Coluccia
- Department of Neurosurgery, Kantonsspital Aarau, Tellstrasse, 5001 Aarau, Switzerland ; Brain Tumor Center, Kantonsspital Aarau, 5001 Aarau, Switzerland
| | - Javier Fandino
- Department of Neurosurgery, Kantonsspital Aarau, Tellstrasse, 5001 Aarau, Switzerland ; Brain Tumor Center, Kantonsspital Aarau, 5001 Aarau, Switzerland
| | - Lucia Schwyzer
- Department of Neurosurgery, Kantonsspital Aarau, Tellstrasse, 5001 Aarau, Switzerland ; Brain Tumor Center, Kantonsspital Aarau, 5001 Aarau, Switzerland
| | - Ruth O'Gorman
- Center for MR Research, University Children's Hospital, 8032 Zürich, Switzerland ; Children's Research Center, University Children's Hospital, 8032 Zürich, Switzerland
| | - Luca Remonda
- Division of Neuroradiology, Department of Radiology, Kantonsspital Aarau, 5001 Aarau, Switzerland
| | - Javier Anon
- Division of Neuroradiology, Department of Radiology, Kantonsspital Aarau, 5001 Aarau, Switzerland
| | - Ernst Martin
- Center for MR Research, University Children's Hospital, 8032 Zürich, Switzerland ; Children's Research Center, University Children's Hospital, 8032 Zürich, Switzerland
| | - Beat Werner
- Center for MR Research, University Children's Hospital, 8032 Zürich, Switzerland ; Children's Research Center, University Children's Hospital, 8032 Zürich, Switzerland
| |
Collapse
|
56
|
Padayachy LC, Fieggen G. Intraoperative Ultrasound-Guidance in Neurosurgery. World Neurosurg 2014; 82:e409-11. [DOI: 10.1016/j.wneu.2013.09.052] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 09/30/2013] [Indexed: 11/25/2022]
|
57
|
N’Djin WA, Burtnyk M, Lipsman N, Bronskill M, Kucharczyk W, Schwartz ML, Chopra R. Active MR-temperature feedback control of dynamic interstitial ultrasound therapy in brain:In vivoexperiments and modeling in native and coagulated tissues. Med Phys 2014; 41:093301. [DOI: 10.1118/1.4892923] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
58
|
Zibly Z, Graves CA, Harnof S, Hadani M, Cohen ZR. Sonoablation and application of MRI guided focused ultrasound in a preclinical model. J Clin Neurosci 2014; 21:1808-14. [PMID: 25012486 DOI: 10.1016/j.jocn.2014.04.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 04/05/2014] [Indexed: 01/16/2023]
Abstract
Stereotaxic sonoablative surgery by MRI guided high intensity focused ultrasound (FUS) holds great potential in disorders of the central nervous system (CNS). We previously described the ExAblate 2000 system (InSightec, Tirat Carmel, Israel), currently in use for various pathologies including uterine, liver, and, breast tumors, and referred to as the "body" system. Using a porcine model we have previously demonstrated, using the body system, the ablative capacity and thermal transfer in the cortex; developed a reproducible and translational model of craniectomy and post-operative recovery in FUS; and determined a grouping strategy based on thermal ablation and pathologic incremental changes in the cortex. Here we describe a novel ExAblate 4000 system that is designed specifically to treat CNS disorders ("head" system). Twenty-two swine underwent an improved wide craniectomy for positioning of the ExAblate 4000 containing 1024 elements arrayed with MRI guidance. Further neurologic and pathological analysis was performed 1 week post-operatively. Subjects underwent a wide craniectomy followed by high intensity MR guided focused ultrasound (MRgHIFU) sonoablation. Thermal ultrasonic ablative lesions were achieved in all subjects (n=22) ranging from 52-65°C following ∼70 consecutive sonications at 80 watts. These subjects were grouped based on thermal ablative lesions and post-operative staging (MRI, gross and microscopic pathology). Our results indicate the reproducibility of a porcine model for cerebral ablation, achieved across a dynamic temperature range, and well tolerated in this cohort. The ExAblate 4000 system is efficient through a wide craniectomy as well as a closed skull and demonstrates a high safety margin. Incremental hemorrhage and necrosis were minimal and energy dependent, indicating MRgHIFU can be used for the treatment of various cerebral pathologies and movement disorders.
Collapse
Affiliation(s)
- Zion Zibly
- Department of Neurological Surgery, The Charles Clore Hospitalization Tower, West Wing Sheba Medical Center, Ramat Gan, Israel.
| | - Christian A Graves
- Department of Pathology, Microbiology, and Immunology, 6439 Garners Ferry Rd., Building 1, Room C27, Columbia, SC 29209, USA
| | - Sagi Harnof
- Department of Neurological Surgery, The Charles Clore Hospitalization Tower, West Wing Sheba Medical Center, Ramat Gan, Israel
| | - Moshe Hadani
- Department of Neurological Surgery, The Charles Clore Hospitalization Tower, West Wing Sheba Medical Center, Ramat Gan, Israel
| | - Zvi R Cohen
- Department of Neurological Surgery, The Charles Clore Hospitalization Tower, West Wing Sheba Medical Center, Ramat Gan, Israel
| |
Collapse
|
59
|
Christian E, Yu C, Apuzzo MLJ. Focused ultrasound: relevant history and prospects for the addition of mechanical energy to the neurosurgical armamentarium. World Neurosurg 2014; 82:354-65. [PMID: 24952224 DOI: 10.1016/j.wneu.2014.06.021] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 06/08/2014] [Accepted: 06/10/2014] [Indexed: 10/25/2022]
Abstract
Although the concept of focused ultrasonography emerged more than 70 years ago, the need for a craniectomy obviated its development as a noninvasive technology. Since then advances in phased array transducers and magnetic resonance imaging technology have resurrected the ultrasound as a noninvasive therapeutic for a plethora of neurological conditions ranging from embolic stroke and intracranial hemorrhage to movement disorders and brain neoplasia. In the same way that stereotactic radiosurgery has fundamentally changed the scope and treatment paradigms of tumor and specifically skull base surgery, focused ultrasound has a similar potential to revolutionize the field of neurological surgery. In addition, focused ultrasound comes without the general complexity or the risks of ionizing radiation that accompany radiosurgery. As the quest for minimally invasive and noninvasive therapeutics continues to define the new neurosurgery, the focused ultrasound evolves to join the neurosurgical armamentarium.
Collapse
Affiliation(s)
- Eisha Christian
- Department of Neurosurgery, Keck School of Medicine of University of Southern California, Los Angeles, California, USA
| | - Cheng Yu
- Department of Neurosurgery, Keck School of Medicine of University of Southern California, Los Angeles, California, USA.
| | - Michael L J Apuzzo
- Department of Neurosurgery, Keck School of Medicine of University of Southern California, Los Angeles, California, USA
| |
Collapse
|
60
|
Zhang S, Li C, Zhou F, Wan M, Wang S. Enhanced lesion-to-bubble ratio on ultrasonic Nakagami imaging for monitoring of high-intensity focused ultrasound. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2014; 33:959-970. [PMID: 24866603 DOI: 10.7863/ultra.33.6.959] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
OBJECTIVES This work explored the feasibility of using ultrasonic Nakagami imaging to enhance the contrast between thermal lesions and bubbles induced by high-intensity focused ultrasound (US) in a transparent tissue-mimicking phantom at different acoustic power levels. METHODS The term "lesion-to-bubble ratio" was proposed and defined as the ratio of the scattered power from the thermal lesion to the scattered power from the bubbles calculated in the various monitoring of images for high-intensity focused US. Two-dimensional radiofrequency data backscattered from the exposed region were captured by a modified diagnostic US scanner to estimate the Nakagami statistical parameter, m, and reconstruct the ultrasonic B-mode images and Nakagami parameter images. The dynamic changes in the lesion-to-bubble ratio over the US exposure procedure were calculated simultaneously and compared among video photos, B-mode images, and Nakagami images for monitoring of high-intensity focused US. RESULTS After a small thermal lesion was induced by high-intensity focused US in the phantom, the lesion-to-bubble ratio values corresponding to the video photo, B-mode image, and Nakagami image were 5.3, 1, and 9.8 dB, respectively. When a large thermal lesion appeared in the phantom, the ratio values increased to 7.2, 3, and 14 dB. During US exposure, the ratio values calculated for the video photo, B-mode image, and Nakagami image began to increase gradually and rose to peak values of 8.3, 2.9, and 14.8 dB at the end of the US exposure. CONCLUSIONS This preliminary study on a tissue-mimicking phantom suggests that Nakagami imaging may have a potential use in enhancing the lesion-to-bubble ratio for monitoring high-intensity focused US. Further studies in vivo and in vitro will be needed to evaluate the potential applications for high-intensity focused US.
Collapse
Affiliation(s)
- Siyuan Zhang
- Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Chong Li
- Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Fanyu Zhou
- Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Mingxi Wan
- Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China.
| | - Supin Wang
- Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| |
Collapse
|
61
|
Wintermark M, Huss DS, Shah BB, Tustison N, Druzgal TJ, Kassell N, Elias WJ. Thalamic connectivity in patients with essential tremor treated with MR imaging-guided focused ultrasound: in vivo fiber tracking by using diffusion-tensor MR imaging. Radiology 2014; 272:202-9. [PMID: 24620914 DOI: 10.1148/radiol.14132112] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To use diffusion-tensor (DT) magnetic resonance (MR) imaging in patients with essential tremor who were treated with transcranial MR imaging-guided focused ultrasound lesion inducement to identify the structural connectivity of the ventralis intermedius nucleus of the thalamus and determine how DT imaging changes correlated with tremor changes after lesion inducement. MATERIALS AND METHODS With institutional review board approval, and with prospective informed consent, 15 patients with medication-refractory essential tremor were enrolled in a HIPAA-compliant pilot study and were treated with transcranial MR imaging-guided focused ultrasound surgery targeting the ventralis intermedius nucleus of the thalamus contralateral to their dominant hand. Fourteen patients were ultimately included. DT MR imaging studies at 3.0 T were performed preoperatively and 24 hours, 1 week, 1 month, and 3 months after the procedure. Fractional anisotropy (FA) maps were calculated from the DT imaging data sets for all time points in all patients. Voxels where FA consistently decreased over time were identified, and FA change in these voxels was correlated with clinical changes in tremor over the same period by using Pearson correlation. RESULTS Ipsilateral brain structures that showed prespecified negative correlation values of FA over time of -0.5 or less included the pre- and postcentral subcortical white matter in the hand knob area; the region of the corticospinal tract in the centrum semiovale, in the posterior limb of the internal capsule, and in the cerebral peduncle; the thalamus; the region of the red nucleus; the location of the central tegmental tract; and the region of the inferior olive. The contralateral middle cerebellar peduncle and bilateral portions of the superior vermis also showed persistent decrease in FA over time. There was strong correlation between decrease in FA and clinical improvement in hand tremor 3 months after lesion inducement (P < .001). CONCLUSION DT MR imaging after MR imaging-guided focused ultrasound thalamotomy depicts changes in specific brain structures. The magnitude of the DT imaging changes after thalamic lesion inducement correlates with the degree of clinical improvement in essential tremor.
Collapse
Affiliation(s)
- Max Wintermark
- From the Department of Radiology, Neuroradiology Division (M.W., N.T., T.J.D.), Department of Neurosurgery (D.S.H., N.K., W.J.E.), and Department of Neurology (B.B.S.), University of Virginia, 1215 Lee St, New Hospital, 1st Floor, Room 1011, Charlottesville, VA 22908-0170; and Department of Radiology, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland (M.W.)
| | | | | | | | | | | | | |
Collapse
|
62
|
Mehić E, Xu JM, Caler CJ, Coulson NK, Moritz CT, Mourad PD. Increased anatomical specificity of neuromodulation via modulated focused ultrasound. PLoS One 2014; 9:e86939. [PMID: 24504255 PMCID: PMC3913583 DOI: 10.1371/journal.pone.0086939] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 12/16/2013] [Indexed: 11/19/2022] Open
Abstract
Transcranial ultrasound can alter brain function transiently and nondestructively, offering a new tool to study brain function now and inform future therapies. Previous research on neuromodulation implemented pulsed low-frequency (250–700 kHz) ultrasound with spatial peak temporal average intensities (ISPTA) of 0.1–10 W/cm2. That work used transducers that either insonified relatively large volumes of mouse brain (several mL) with relatively low-frequency ultrasound and produced bilateral motor responses, or relatively small volumes of brain (on the order of 0.06 mL) with relatively high-frequency ultrasound that produced unilateral motor responses. This study seeks to increase anatomical specificity to neuromodulation with modulated focused ultrasound (mFU). Here, ‘modulated’ means modifying a focused 2-MHz carrier signal dynamically with a 500-kHz signal as in vibro-acoustography, thereby creating a low-frequency but small volume (approximately 0.015 mL) source of neuromodulation. Application of transcranial mFU to lightly anesthetized mice produced various motor movements with high spatial selectivity (on the order of 1 mm) that scaled with the temporal average ultrasound intensity. Alone, mFU and focused ultrasound (FUS) each induced motor activity, including unilateral motions, though anatomical location and type of motion varied. Future work should include larger animal models to determine the relative efficacy of mFU versus FUS. Other studies should determine the biophysical processes through which they act. Also of interest is exploration of the potential research and clinical applications for targeted, transcranial neuromodulation created by modulated focused ultrasound, especially mFU’s ability to produce compact sources of ultrasound at the very low frequencies (10–100s of Hertz) that are commensurate with the natural frequencies of the brain.
Collapse
Affiliation(s)
- Edin Mehić
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
| | - Julia M. Xu
- Department of Materials Science and Engineering, University of Washington, Seattle, Washington, United States of America
| | - Connor J. Caler
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
| | - Nathaniel K. Coulson
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
| | - Chet T. Moritz
- Department of Rehabilitation Medicine, University of Washington, Seattle, Washington, United States of America
- Department of Physiology and Biophysics, University of Washington, Seattle, Washington, United States of America
| | - Pierre D. Mourad
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
- Applied Physics Laboratory, University of Washington, Seattle, Washington, United States of America
- Department of Neurological Surgery, University of Washington, Seattle, Washington, United States of America
- Department of Engineering and Mathematics, University of Washington, Bothell, Washington, United States of America
- * E-mail:
| |
Collapse
|
63
|
High-Intensity Focussed Ultrasound and Radio-Frequency Ablation for Bone Metastasis Treatment. BONE METASTASES 2014. [DOI: 10.1007/978-94-007-7569-5_14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
64
|
Kyriakou A, Neufeld E, Werner B, Paulides MM, Szekely G, Kuster N. A review of numerical and experimental compensation techniques for skull-induced phase aberrations in transcranial focused ultrasound. Int J Hyperthermia 2013; 30:36-46. [PMID: 24325307 DOI: 10.3109/02656736.2013.861519] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The development of phased array transducers and their integration with magnetic resonance (MR) guidance and thermal monitoring has established transcranial MR-guided focused ultrasound (tcMRgFUS) as an attractive non-invasive modality for neurosurgical interventions. The presence of the skull, however, compromises the efficiency of transcranial FUS (tcFUS) therapy, as its heterogeneous nature and acoustic characteristics induce significant phase aberrations and energy attenuation, especially at the higher acoustic frequencies employed in tcFUS thermal therapy. These aberrations may distort and shift the acoustic focus as well as induce heating at the patient's scalp and skull bone. Phased array transducers feature hundreds of elements that can be driven individually, each with its own phase and amplitude. This feature allows for compensation of skull-induced aberrations by calculation and application of appropriate phase and amplitude corrections. In this paper, we illustrate the importance of precise refocusing and provide a comprehensive review of the wide variety of numerical and experimental techniques that have been used to estimate these corrections.
Collapse
Affiliation(s)
- Adamos Kyriakou
- IT'IS Foundation for Research on Information Technologies in Society , Zurich , Switzerland
| | | | | | | | | | | |
Collapse
|
65
|
Abstract
Transcranial MRI-guided focused ultrasound (TcMRgFUS) is an old idea but a new technology that may change the entire clinical field of the neurosciences. TcMRgFUS has no cumulative effect, and it is applicable for repeatable treatments, controlled by real-time dosimetry, and capable of immediate tissue destruction. Most importantly, it has extremely accurate targeting and constant monitoring. It is potentially more precise than proton beam therapy and definitely more cost effective. Neuro-oncology may be the most promising area of future TcMRgFUS applications.
Collapse
|
66
|
[On the diversity of applications for ultrasound]. Radiologe 2013; 53:707-8. [PMID: 23818014 DOI: 10.1007/s00117-013-2528-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
67
|
Monteith SJ, Kassell NF, Goren O, Harnof S. Transcranial MR-guided focused ultrasound sonothrombolysis in the treatment of intracerebral hemorrhage. Neurosurg Focus 2013; 34:E14. [DOI: 10.3171/2013.2.focus1313] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Intracerebral hemorrhage remains a significant cause of morbidity and mortality. Current surgical therapies aim to use a minimally invasive approach to remove as much of the clot as possible without causing undue disruption to surrounding neural structures. Transcranial MR-guided focused ultrasound (MRgFUS) surgery is an emerging technology that permits a highly concentrated focal point of ultrasound energy to be deposited to a target deep within the brain without an incision or craniotomy. With appropriate ultrasound parameters it has been shown that MRgFUS can effectively liquefy large-volume blood clots through the human calvaria. In this review the authors discuss the rationale for using MRgFUS to noninvasively liquefy intracerebral hemorrhage (ICH), thereby permitting minimally invasive aspiration of the liquefied clot via a small drainage tube. The mechanism of action of MRgFUS sonothrombolysis; current investigational work with in vitro, in vivo, and cadaveric models of ICH; and the potential clinical application of this disruptive technology for the treatment of ICH are discussed.
Collapse
Affiliation(s)
- Stephen J. Monteith
- 1Department of Neurosurgery, University of Virginia Health System, Charlottesville, Virginia; and
| | - Neal F. Kassell
- 1Department of Neurosurgery, University of Virginia Health System, Charlottesville, Virginia; and
| | - Oded Goren
- 2Department of Neurosurgery, Sheba Medical Center, Tel Hashomer, Israel
| | - Sagi Harnof
- 2Department of Neurosurgery, Sheba Medical Center, Tel Hashomer, Israel
| |
Collapse
|
68
|
Harnof S, Zibly Z, Cohen Z, Shaw A, Schlaff C, Kassel NF. Cranial nerve threshold for thermal injury induced by MRI-guided high-intensity focused ultrasound (MRgHIFU): preliminary results on an optic nerve model. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2013; 60:702-705. [PMID: 23549530 DOI: 10.1109/tuffc.2013.2618] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Future clinical applications of magnetic resonance imaging-guided high-intensity focused ultrasound (MRgHIFU) are moving toward the management of different intracranial pathologies. We sought to validate the production, safety, and efficacy of thermal injury to cranial nerves generated by MRgHIFU. In this study, five female domestic pigs underwent a standard bifrontal craniectomy under general anesthesia. Treatment was then given using an MRgHIFU system to induce hyperthermic ablative sonication (6 to 10 s; 50 to 2000 J.) Histological analyses were done to confirm nerve damage; temperature measured on the optic nerve was approximately 53.4°C (range: 39°C to 70°C.) Histology demonstrated a clear definition between a necrotic, transitional zone, and normal tissue. MRgHIFU induces targeted thermal injury to nervous tissue within a specific threshold of 50°C to 60°C with the tissue near the sonication center yielding the greatest effect; adjacent tissue showed minimal changes. Additional studies utilizing this technology are required to further establish accurate threshold parameters for optic nerve thermo-ablation.
Collapse
Affiliation(s)
- Sagi Harnof
- Department of Neurosurgery, Chaim Sheba Medical Center, Tel Hashomer, Israel.
| | | | | | | | | | | |
Collapse
|
69
|
|
70
|
Chauvet D, Marsac L, Pernot M, Boch AL, Guillevin R, Salameh N, Souris L, Darrasse L, Fink M, Tanter M, Aubry JF. Targeting accuracy of transcranial magnetic resonance-guided high-intensity focused ultrasound brain therapy: a fresh cadaver model. J Neurosurg 2013; 118:1046-52. [PMID: 23451909 DOI: 10.3171/2013.1.jns12559] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT This work aimed at evaluating the accuracy of MR-guided high-intensity focused ultrasound (MRgHIFU) brain therapy in human cadaver heads. METHODS Eighteen heads of fresh human cadavers were removed with a dedicated protocol preventing intracerebral air penetration. The MR images allowed determination of the ultrasonic target: a part of the thalamic nucleus ventralis intermedius implicated in essential tremor. Osseous aberrations were corrected with simulation-based time reversal by using CT data from the heads. The ultrasonic session was performed with a 512-element phased-array transducer system operating at 1 MHz under stereotactic conditions with thermometric real-time MR monitoring performed using a 1.5-T imager. RESULTS Dissection, imaging, targeting, and planning have validated the feasibility of this human cadaver model. The average temperature elevation measured by proton resonance frequency shift was 7.9°C ± 3°C. Based on MRI data, the accuracy of MRgHIFU is 0.4 ± 1 mm along the right/left axis, 0.7 ± 1.2 mm along the dorsal/ventral axis, and 0.5 ± 2.4 mm in the rostral/caudal axis. CONCLUSIONS Despite its limits (temperature, vascularization), the human cadaver model is effective for studying the accuracy of MRgHIFU brain therapy. With the 1-MHz system investigated here, there is millimetric accuracy.
Collapse
Affiliation(s)
- Dorian Chauvet
- Department of Neurosurgery, Groupe Hospitalier Pitié Salpêtrière, Paris, France
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
71
|
Medel R, Monteith SJ, Elias WJ, Eames M, Snell J, Sheehan JP, Wintermark M, Jolesz FA, Kassell NF. Magnetic resonance-guided focused ultrasound surgery: Part 2: A review of current and future applications. Neurosurgery 2013; 71:755-63. [PMID: 22791029 DOI: 10.1227/neu.0b013e3182672ac9] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Magnetic resonance-guided focused ultrasound surgery (MRgFUS) is a novel combination of technologies that is actively being realized as a noninvasive therapeutic tool for a myriad of conditions. These applications are reviewed with a focus on neurological use. A combined search of PubMed and MEDLINE was performed to identify the key events and current status of MRgFUS, with a focus on neurological applications. MRgFUS signifies a potentially ideal device for the treatment of neurological diseases. As it is nearly real time, it allows monitored provision of treatment location and energy deposition; is noninvasive, thereby limiting or eliminating disruption of normal tissue; provides focal delivery of therapeutic agents; enhances radiation delivery; and permits modulation of neural function. Multiple clinical applications are currently in clinical use and many more are under active preclinical investigation. The therapeutic potential of MRgFUS is expanding rapidly. Although clinically in its infancy, preclinical and early-phase I clinical trials in neurosurgery suggest a promising future for MRgFUS. Further investigation is necessary to define its true potential and impact.
Collapse
Affiliation(s)
- Ricky Medel
- Department of Neurosurgery, University of Virginia Health Sciences Center, University of University, Charlottesville, Virginia 22902, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
72
|
King RL, Brown JR, Newsome WT, Pauly KB. Effective parameters for ultrasound-induced in vivo neurostimulation. ULTRASOUND IN MEDICINE & BIOLOGY 2013; 39:312-31. [PMID: 23219040 DOI: 10.1016/j.ultrasmedbio.2012.09.009] [Citation(s) in RCA: 293] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 08/01/2012] [Accepted: 09/11/2012] [Indexed: 05/13/2023]
Abstract
Ultrasound-induced neurostimulation has recently gained increasing attention, but little is known about the mechanisms by which it affects neural activity or about the range of acoustic parameters and stimulation protocols that elicit responses. We have established conditions for transcranial stimulation of the nervous system in vivo, using the mouse somatomotor response. We report that (1) continuous-wave stimuli are as effective as or more effective than pulsed stimuli in eliciting responses, and responses are elicited with stimulus onset rather than stimulus offset; (2) stimulation success increases as a function of both acoustic intensity and acoustic duration; (3) interactions of intensity and duration suggest that successful stimulation results from the integration of stimulus amplitude over a time interval of 50 to 150 ms; and (4) the motor response elicited appears to be an all-or-nothing phenomenon, meaning stronger stimulus intensities and durations increase the probability of a motor response without affecting the duration or strength of the response.
Collapse
Affiliation(s)
- Randy L King
- Department of Bioengineering, Stanford University, Stanford, CA, USA.
| | | | | | | |
Collapse
|
73
|
Monteith S, Sheehan J, Medel R, Wintermark M, Eames M, Snell J, Kassell NF, Elias WJ. Potential intracranial applications of magnetic resonance–guided focused ultrasound surgery. J Neurosurg 2013; 118:215-21. [DOI: 10.3171/2012.10.jns12449] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Magnetic resonance–guided focused ultrasound surgery (MRgFUS) has the potential to create a shift in the treatment paradigm of several intracranial disorders. High-resolution MRI guidance combined with an accurate method of delivering high doses of transcranial ultrasound energy to a discrete focal point has led to the exploration of noninvasive treatments for diseases traditionally treated by invasive surgical procedures. In this review, the authors examine the current intracranial applications under investigation and explore other potential uses for MRgFUS in the intracranial space based on their initial cadaveric studies.
Collapse
Affiliation(s)
| | | | | | - Max Wintermark
- 2Neuroradiology, University of Virginia Health System; and
| | - Matthew Eames
- 3Focused Ultrasound Foundation, Charlottesville, Virginia
| | - John Snell
- 3Focused Ultrasound Foundation, Charlottesville, Virginia
| | - Neal F. Kassell
- 1Departments of Neurological Surgery and
- 3Focused Ultrasound Foundation, Charlottesville, Virginia
| | | |
Collapse
|
74
|
Monteith SJ, Medel R, Kassell NF, Wintermark M, Eames M, Snell J, Zadicario E, Grinfeld J, Sheehan JP, Elias WJ. Transcranial magnetic resonance–guided focused ultrasound surgery for trigeminal neuralgia: a cadaveric and laboratory feasibility study. J Neurosurg 2013; 118:319-28. [DOI: 10.3171/2012.10.jns12186] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Transcranial MR-guided focused ultrasound surgery (MRgFUS) is evolving as a treatment modality in neurosurgery. Until now, the trigeminal nerve was believed to be beyond the treatment envelope of existing high-frequency transcranial MRgFUS systems. In this study, the authors explore the feasibility of targeting the trigeminal nerve in a cadaveric model with temperature assessments using computer simulations and an in vitro skull phantom model fitted with thermocouples.
Methods
Six trigeminal nerves from 4 unpreserved cadavers were targeted in the first experiment. Preprocedural CT scanning of the head was performed to allow for a skull correction algorithm. Three-Tesla, volumetric, FIESTA MRI sequences were performed to delineate the trigeminal nerve and any vascular structures of the cisternal segment. The cadaver was positioned in a focused ultrasound transducer (650-kHz system, ExAblate Neuro, InSightec) so that the focus of the transducer was centered at the proximal trigeminal nerve, allowing for targeting of the root entry zone (REZ) and the cisternal segment. Real-time, 2D thermometry was performed during the 10- to 30-second sonication procedures. Post hoc MR thermometry was performed on a computer workstation at the conclusion of the procedure to analyze temperature effects at neuroanatomical areas of interest. Finally, the region of the trigeminal nerve was targeted in a gel phantom encased within a human cranium, and temperature changes in regions of interest in the skull base were measured using thermocouples.
Results
The trigeminal nerves were clearly identified in all cadavers for accurate targeting. Sequential sonications of 25–1500 W for 10–30 seconds were successfully performed along the length of the trigeminal nerve starting at the REZ. Real-time MR thermometry confirmed the temperature increase as a narrow focus of heating by a mean of 10°C. Postprocedural thermometry calculations and thermocouple experiments in a phantom skull were performed and confirmed minimal heating of adjacent structures including the skull base, cranial nerves, and cerebral vessels. For targeting, inclusion of no-pass regions through the petrous bone decreased collateral heating in the internal acoustic canal from 16.7°C without blocking to 5.7°C with blocking. Temperature at the REZ target decreased by 3.7°C with blocking. Similarly, for midcisternal targeting, collateral heating at the internal acoustic canal was improved from a 16.3°C increase to a 4.9°C increase. Blocking decreased the target temperature increase by 4.4°C for the same power settings.
Conclusions
This study demonstrates focal heating of up to 18°C in a cadaveric trigeminal nerve at the REZ and along the cisternal segment with transcranial MRgFUS. Significant heating of the skull base and surrounding neural structures did not occur with implementation of no-pass regions. However, in vivo studies are necessary to confirm the safety and efficacy of this potentially new, noninvasive treatment.
Collapse
Affiliation(s)
| | | | - Neal F. Kassell
- 1Departments of Neurosurgery and
- 2Focused Ultrasound Surgery Foundation, Charlottesville, Virginia; and
| | | | - Matthew Eames
- 2Focused Ultrasound Surgery Foundation, Charlottesville, Virginia; and
| | - John Snell
- 2Focused Ultrasound Surgery Foundation, Charlottesville, Virginia; and
| | | | | | | | | |
Collapse
|
75
|
Monteith SJ, Harnof S, Medel R, Popp B, Wintermark M, Lopes MBS, Kassell NF, Elias WJ, Snell J, Eames M, Zadicario E, Moldovan K, Sheehan J. Minimally invasive treatment of intracerebral hemorrhage with magnetic resonance-guided focused ultrasound. J Neurosurg 2013; 118:1035-45. [PMID: 23330996 DOI: 10.3171/2012.12.jns121095] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Intracerebral hemorrhage (ICH) is a major cause of death and disability throughout the world. Surgical techniques are limited by their invasive nature and the associated disability caused during clot removal. Preliminary data have shown promise for the feasibility of transcranial MR-guided focused ultrasound (MRgFUS) sonothrombolysis in liquefying the clotted blood in ICH and thereby facilitating minimally invasive evacuation of the clot via a twist-drill craniostomy and aspiration tube. METHODS AND RESULTS In an in vitro model, the following optimum transcranial sonothrombolysis parameters were determined: transducer center frequency 230 kHz, power 3950 W, pulse repetition rate 1 kHz, duty cycle 10%, and sonication duration 30 seconds. Safety studies were performed in swine (n = 20). In a swine model of ICH, MRgFUS sonothrombolysis of 4 ml ICH was performed. Magnetic resonance imaging and histological examination demonstrated complete lysis of the ICH without additional brain injury, blood-brain barrier breakdown, or thermal necrosis due to sonothrombolysis. A novel cadaveric model of ICH was developed with 40-ml clots implanted into fresh cadaveric brains (n = 10). Intracerebral hemorrhages were successfully liquefied (> 95%) with transcranial MRgFUS in a highly accurate fashion, permitting minimally invasive aspiration of the lysate under MRI guidance. CONCLUSIONS The feasibility of transcranial MRgFUS sonothrombolysis was demonstrated in in vitro and cadaveric models of ICH. Initial in vivo safety data in a swine model of ICH suggest the process to be safe. Minimally invasive treatment of ICH with MRgFUS warrants evaluation in the setting of a clinical trial.
Collapse
Affiliation(s)
- Stephen J Monteith
- Department of Neurological Surgery, University of Virginia Health System, Charlottesville, Virginia 22908, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
76
|
Yang PS, Kim H, Lee W, Bohlke M, Park S, Maher TJ, Yoo SS. Transcranial focused ultrasound to the thalamus is associated with reduced extracellular GABA levels in rats. Neuropsychobiology 2012; 65:153-60. [PMID: 22378299 DOI: 10.1159/000336001] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Accepted: 12/13/2011] [Indexed: 01/03/2023]
Abstract
OBJECTIVE Transcranial focused ultrasound (FUS), with its ability to non-invasively modulate the excitability of region-specific brain areas, is gaining attention as a potential neurotherapeutic modality. The aim of this study was to examine whether or not FUS administered to the brain could alter the extracellular levels of glutamate and γ-aminobutyric acid (GABA), which are representative excitatory and inhibitory amino acid neurotransmitters, respectively. METHODS FUS, delivered in the form of a train of pulses, was applied to the thalamus of Sprague-Dawley rats transcranially. Glutamate and GABA were directly sampled from the frontal lobe of the rat brain via a direct microdialysis technique before, during, and after the sonication. The dialysate concentrations were determined by high-performance liquid chromatography. RESULTS The individual levels of the neurotransmitters sampled were normalized to the baseline level for each rat. In terms of the changes in extracellular glutamate levels, there was no difference between the FUS-treated group and the unsonicated control group. However, extracellular GABA levels started to decrease upon sonication and remained reduced (approximately 20% below baseline; repeated-measures ANOVA, p < 0.05, adjusted for multiple comparisons) compared to the control group. CONCLUSION The ability to modulate region-specific brain activity, along with the present evidence of the ability to modulate neurotransmission, demonstrates the potential utility of FUS as a completely new non-invasive therapeutic modality.
Collapse
Affiliation(s)
- Po Song Yang
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | | | | | | | | | | | | |
Collapse
|
77
|
Wei KC, Tsai HC, Lu YJ, Yang HW, Hua MY, Wu MF, Chen PY, Huang CY, Yen TC, Liu HL. Neuronavigation-guided focused ultrasound-induced blood-brain barrier opening: a preliminary study in swine. AJNR Am J Neuroradiol 2012; 34:115-20. [PMID: 22723060 DOI: 10.3174/ajnr.a3150] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE FUS-induced BBB opening is a promising technique for noninvasive and local delivery of drugs into the brain. Here we propose the novel use of a neuronavigation system to guide the FUS-induced BBB opening procedure and investigate its feasibility in vivo in large animals. MATERIALS AND METHODS We developed an interface between the neuronavigator and FUS to allow guidance of the focal energy produced by the FUS transducer. The system was tested in 29 swine by more than 40 sonication procedures and evaluated by MR imaging. Gd-DTPA concentration was quantitated in vivo by MR imaging R1 relaxometry and compared with ICP-OES assay. Brain histology after FUS exposure was investigated using H&E and TUNEL staining. RESULTS Neuronavigation could successfully guide the focal beam, with precision comparable to neurosurgical stereotactic procedures (2.3 ± 0.9 mm). A FUS pressure of 0.43 MPa resulted in consistent BBB opening. Neuronavigation-guided BBB opening increased Gd-DTPA deposition by up to 1.83 mmol/L (a 140% increase). MR relaxometry demonstrated high correlation with ICP-OES measurements (r(2) = 0.822), suggesting that Gd-DTPA deposition can be directly measured by imaging. CONCLUSIONS Neuronavigation provides sufficient precision for guiding FUS to temporally and locally open the BBB. Gd-DTPA deposition in the brain can be quantified by MR relaxometry, providing a potential tool for the in vivo quantification of therapeutic agents in CNS disease treatment.
Collapse
Affiliation(s)
- K-C Wei
- Department of Neurosurgery, Chang-Gung University and Memorial Hospital, Taoyuan, Taiwan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
78
|
Zhang S, Zhou F, Wan M, Wei M, Fu Q, Wang X, Wang S. Feasibility of using Nakagami distribution in evaluating the formation of ultrasound-induced thermal lesions. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2012; 131:4836-4844. [PMID: 22712954 DOI: 10.1121/1.4711005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The acoustic posterior shadowing effects of bubbles influence the accuracy for defining the location and range of ablated thermal lesions during focused ultrasound surgery when using ultrasonic monitoring imaging. This paper explored the feasibility of using Nakagami distribution to evaluate the ablated region induced by focused ultrasound exposures at different acoustic power levels in transparent tissue-mimicking phantoms. The mean value of the Nakagami parameter m was about 0.5 in the cavitation region and increased to around 1 in the ablated region. Nakagami images were not subject to significant shadowing effects of bubbles. Ultrasound-induced thermal lesions observed in the photos and Nakagami images were overshadowed by bubbles in the B-mode images. The lesion size predicted in the Nakagami images was smaller than that predicted in the photos due to the sub resolvable effect of Nakagami imaging at the interface. This preliminary study on tissue-mimicking phantom suggested that the Nakagami parameter m may have the potential use in evaluating the formation of ultrasound-induced thermal lesion when the shadowing effect of bubbles is strong while the thermal lesion was small. Further studies in vivo and in vitro will be needed to evaluate the potential application.
Collapse
Affiliation(s)
- Siyuan Zhang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China
| | | | | | | | | | | | | |
Collapse
|
79
|
Pinton G, Aubry JF, Fink M, Tanter M. Numerical prediction of frequency dependent 3D maps of mechanical index thresholds in ultrasonic brain therapy. Med Phys 2012; 39:455-67. [PMID: 22225316 DOI: 10.1118/1.3670376] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Therapeutic ultrasound has been used in the brain for thrombolysis and high intensity focused ultrasound (HIFU) therapy. A low-frequency clinical study of sonothrombolysis, called the transcranial low-frequency ultrasound-mediated thrombolysis in brain ischemia (TRUMBI), has revealed an increased incidence of hemorrhage, which may have been caused by cavitation. The goal of this study is to determine if there is a comparable risk of generating cavitation during HIFU brain therapy at different frequencies. METHODS Two approaches are used to transmit acoustic energy through the skull to the brain: low-frequency ultrasound, with a wavelength that is larger than the skull thickness, and high frequency ultrasound, that is sensitive to aberrations and must use corrective techniques. At high frequency, the mechanical index (MI) is lower, which translates to a higher cavitation threshold. In addition to the nonfocused geometry of the 300 kHz sonothrombolysis treatment device, two types of focused therapeutic transducers were modeled: a low frequency 220 kHz transducer and a 1 MHz transducer that required aberration correction with a time-reversal approach, representing the lowest and highest frequencies currently used. The acoustic field was modeled with a finite difference fullwave acoustic code developed for large scale computations, that is, capable of simulating the entire brain volume. Various MI thresholds and device geometries were considered to determine the regions of the brain that have an increased probability of cavitation events. RESULTS For an equivalent energy deposition rate, it is shown that at a low frequency there is a significant volume of the brain that is above the MI thresholds. At a high frequency, the volume is over 3 orders of magnitude smaller, and it is entirely confined to a compact focal spot. CONCLUSIONS The significant frequency dependence of the volumes with an increased probability of cavitation can be attributed to two factors: First, the volume encompassed by the focal region depends on the cube of the frequency. Second, the heat deposition increases with frequency. In conclusion, according to these simulations, the acoustic environment during HIFU brain therapy at 1 MHz is not conducive to a high probability of cavitation in extended regions of the brain.
Collapse
|
80
|
Bor-Seng-Shu E, Nogueira RDC, Figueiredo EG, Evaristo EF, Conforto AB, Teixeira MJ. Sonothrombolysis for acute ischemic stroke: a systematic review of randomized controlled trials. Neurosurg Focus 2012; 32:E5. [PMID: 22208898 DOI: 10.3171/2011.10.focus11251] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Sonothrombolysis has recently been considered an emerging modality for the treatment of stroke. The purpose of the present paper was to review randomized clinical studies concerning the effects of sonothrombolysis associated with tissue plasminogen activator (tPA) on acute ischemic stroke. METHODS Systematic searches for literature published between January 1996 and July 2011 were performed for studies regarding sonothrombolysis combined with tPA for acute ischemic stroke. Only randomized controlled trials were included. Data extraction was based on ultrasound variables, patient characteristics, and outcome variables (rate of intracranial hemorrhages and arterial recanalization). RESULTS Four trials were included in this study; 2 trials evaluated the effect of transcranial Doppler (TCD) ultrasonography on sonothrombolysis, and 2 addressed transcranial color-coded duplex (TCCD) ultrasonography. The frequency of ultrasound waves varied from 1.8 to 2 MHz. The duration of thrombus exposure to ultrasound energy ranged from 60 to 120 minutes. Sample sizes were small, recanalization was evaluated at different time points (60 and 120 minutes), and inclusion criteria were heterogeneous. Sonothrombolysis combined with tPA did not lead to an increase in symptomatic intracranial hemorrhagic complications. Two studies demonstrated that patients treated with ultrasound combined with tPA had statistically significant higher rates of recanalization than patients treated with tPA alone. CONCLUSIONS Despite the heterogeneity and the limitations of the reviewed studies, there is evidence that sonothrombolysis associated with tPA is a safe procedure and results in an increased rate of recanalization in the setting of acute ischemic stroke when wave frequencies and energy intensities of diagnostic ultrasound systems are used.
Collapse
Affiliation(s)
- Edson Bor-Seng-Shu
- Division of Neurological Surgery, Hospital das Clinicas, University of Sao Paulo School of Medicine, Sao Paulo, Brazil.
| | | | | | | | | | | |
Collapse
|
81
|
|
82
|
Serrone J, Kocaeli H, Douglas Mast T, Burgess MT, Zuccarello M. The potential applications of high-intensity focused ultrasound (HIFU) in vascular neurosurgery. J Clin Neurosci 2012; 19:214-21. [DOI: 10.1016/j.jocn.2011.07.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Revised: 06/29/2011] [Accepted: 07/01/2011] [Indexed: 11/25/2022]
|
83
|
Jeanmonod D, Werner B, Morel A, Michels L, Zadicario E, Schiff G, Martin E. Transcranial magnetic resonance imaging–guided focused ultrasound: noninvasive central lateral thalamotomy for chronic neuropathic pain. Neurosurg Focus 2012; 32:E1. [PMID: 22208894 DOI: 10.3171/2011.10.focus11248] [Citation(s) in RCA: 257] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Object
Recent technological developments open the field of therapeutic application of focused ultrasound to the brain through the intact cranium. The goal of this study was to apply the new transcranial magnetic resonance imaging–guided focused ultrasound (tcMRgFUS) technology to perform noninvasive central lateral thalamotomies (CLTs) as a treatment for chronic neuropathic pain.
Methods
In 12 patients suffering from chronic therapy-resistant neuropathic pain, tcMRgFUS CLT was proposed. In 11 patients, precisely localized thermal ablations of 3–4 mm in diameter were produced in the posterior part of the central lateral thalamic nucleus at peak temperatures between 51°C and 64°C with the aid of real-time patient monitoring and MR imaging and MR thermometry guidance. The treated neuropathic pain syndromes had peripheral (5 patients) or central (6 patients) origins and covered all body parts (face, arm, leg, trunk, and hemibody).
Results
Patients experienced mean pain relief of 49% at the 3-month follow-up (9 patients) and 57% at the 1-year follow-up (8 patients). Mean improvement according to the visual analog scale amounted to 42% at 3 months and 41% at 1 year. Six patients experienced immediate and persisting somatosensory improvements. Somatosensory and vestibular clinical manifestations were always observed during sonication time because of ultrasound-based neuronal activation and/or initial therapeutic effects. Quantitative electroencephalography (EEG) showed a significant reduction in EEG spectral overactivities. Thermal ablation sites showed sharply delineated ellipsoidal thermolesions surrounded by short-lived vasogenic edema. Lesion reconstructions (18 lesions in 9 patients) demonstrated targeting precision within a millimeter for all 3 coordinates. There was 1 complication, a bleed in the target with ischemia in the motor thalamus, which led to the introduction of 2 safety measures, that is, the detection of a potential cavitation by a cavitation detector and the maintenance of sonication temperatures below 60°C.
Conclusions
The authors assert that tcMRgFUS represents a noninvasive, precise, and radiation-free neurosurgical technique for the treatment of neuropathic pain. The procedure avoids mechanical brain tissue shift and eliminates the risk of infection. The possibility of applying sonication thermal spots free from trajectory restrictions should allow one to optimize target coverage. The real-time continuous MR imaging and MR thermometry monitoring of targeting accuracy and thermal effects are major factors in optimizing precision, safety, and efficacy in an outpatient context.
Collapse
Affiliation(s)
- Daniel Jeanmonod
- 1Department of Functional Neurosurgery and
- 2Center of Ultrasound Functional Neurosurgery, Solothurn
| | - Beat Werner
- 3MR-Center, University Children's Hospital, Zürich, Switzerland; and
| | - Anne Morel
- 1Department of Functional Neurosurgery and
- 4Center for Clinical Research, University Hospital Zürich
| | - Lars Michels
- 1Department of Functional Neurosurgery and
- 3MR-Center, University Children's Hospital, Zürich, Switzerland; and
| | | | | | - Ernst Martin
- 3MR-Center, University Children's Hospital, Zürich, Switzerland; and
| |
Collapse
|
84
|
Transcranial ultrasound for arteriovenous malformations: something old is new again. World Neurosurg 2011; 77:269-70. [PMID: 22120323 DOI: 10.1016/j.wneu.2011.07.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Accepted: 07/27/2011] [Indexed: 11/21/2022]
|
85
|
Mason TJ. Therapeutic ultrasound an overview. ULTRASONICS SONOCHEMISTRY 2011; 18:847-852. [PMID: 21316286 DOI: 10.1016/j.ultsonch.2011.01.004] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Revised: 01/07/2011] [Accepted: 01/10/2011] [Indexed: 05/30/2023]
Abstract
Therapeutic ultrasound is defined as the use of ultrasound for the treatment of diseased or injured organs or bodily structures and is quite distinct from diagnostic ultrasound. There were many early attempts in the past to use ultrasound in therapy for a variety of applications and while some of these have not been pursued others have led on to clinical applications which are now used routinely. Such progress has been made possible by a number of factors including advances in transducer design, more accurate measurement and calibration of acoustic power and careful experiments to determine the precise nature of chemical processes taking place during and following the exposure of tissue to ultrasound. Major advances have been made in some fields where ultrasound is used such as physiotherapy, surgical instruments, chemotherapy, drug delivery and more recently, high intensity focused ultrasound (HIFU). The last of these has seen enormous activity leading to the formation of the International Society of Therapeutic Ultrasound and a number of very well attended regular specialist meetings. In this review some historical perspectives of therapeutic ultrasound and progress in the field since the early 1990's will be presented.
Collapse
Affiliation(s)
- Timothy J Mason
- The Sonochemistry Centre at Coventry University, Faculty of Health and Life Sciences, Priory Street, Coventry CV1 5FB, United Kingdom.
| |
Collapse
|
86
|
Hoffer FA. Interventional oncology: the future. Pediatr Radiol 2011; 41 Suppl 1:S201-6. [PMID: 21523599 DOI: 10.1007/s00247-011-1990-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 01/04/2011] [Accepted: 01/13/2011] [Indexed: 01/03/2023]
Abstract
Interventional radiology techniques to treat oncological disease have already shown value in adults. The adoption and development of interventional oncology (IO) in children have been more limited and challenging. This relates to the approval process for new devices and agents, oncology group protocol limitations and the inherent hesitation of trying new treatments in children. This paper will discuss how new procedures are developed and approved, and the new therapies that will become available to better treat pediatric malignancies. Bringing the benefits of IO to children will require initiative on the part of pediatric diagnostic and interventional radiologists as well as the cooperation of our clinical colleagues.
Collapse
Affiliation(s)
- Fredric A Hoffer
- Department of Radiology, University of Washington, 3904 NE Belvoir Place, Seattle, WA 98105, USA.
| |
Collapse
|
87
|
Dick EA, Gedroyc WMW. ExAblate magnetic resonance-guided focused ultrasound system in multiple body applications. Expert Rev Med Devices 2011; 7:589-97. [PMID: 20822382 DOI: 10.1586/erd.10.38] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Focused ultrasound surgery (FUS) is a completely noninvasive method of thermally destroying a target tissue while sparing adjacent tissues and organs. Treatment is relatively painless and can be carried out under conscious sedation on an out-patient basis. The combination of magnetic resonance guidance with FUS (MRgFUS) provides the ability to plan and monitor treatments in near real-time, further increasing the safety profile of MRgFUS. This technology provides a very personalized treatment, adjusted to the individual patient anatomy, pathology and treatment response, hence it meets the needs of patients, as well as of physicians. MRgFUS has been used extensively in the successful treatment of uterine fibroids, and has been shown to be an effective treatment in the breast and in bone metastases in smaller scale studies. It shows great potential in the treatment of prostate and liver tumors, as well as in the brain and facet joints.
Collapse
Affiliation(s)
- E A Dick
- Department of MRI, St Mary's Hospital, London, UK
| | | |
Collapse
|
88
|
Colen RR, Jolesz FA. Future potential of MRI-guided focused ultrasound brain surgery. Neuroimaging Clin N Am 2010; 20:355-66. [PMID: 20708551 DOI: 10.1016/j.nic.2010.05.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Magnetic resonance image-guided focused ultrasound surgery (MRgFUS) has surfaced as a viable noninvasive image-guided therapeutic method that integrates focused ultrasound (FUS), the therapeutic component, with magnetic resonance imaging (MRI), the image guidance module, into a real-time therapy delivery system with closed-loop control of energy delivery. The main applications for MRgFUS of the brain are thermal ablations for brain tumors and functional neurosurgery, and nonthermal, nonablative uses for disruption of the blood brain barrier (BBB) or blood clot and hematoma dissolution by liquification. The disruption of the BBB by FUS can be used for targeted delivery of chemotherapy and other therapeutic agents. MRI is used preoperatively for target definition and treatment planning, intraoperatively for procedure monitoring and control, and postoperatively for validating treatment success. Although challenges still remain, this integrated noninvasive therapy delivery system is anticipated to change current treatment paradigms in neurosurgery and the clinical neurosciences.
Collapse
Affiliation(s)
- Rivka R Colen
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
| | | |
Collapse
|
89
|
Holtel MR. Emerging Technology in Head and Neck Ultrasonography. Otolaryngol Clin North Am 2010; 43:1267-74, vii. [DOI: 10.1016/j.otc.2010.08.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
90
|
Deffieux T, Konofagou EE. Numerical study of a simple transcranial focused ultrasound system applied to blood-brain barrier opening. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2010; 57:2637-53. [PMID: 21156360 PMCID: PMC3968803 DOI: 10.1109/tuffc.2010.1738] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
In this paper, we investigate the focalization properties of single-element transducers at low frequencies (300 to 1000 kHz) through primate and human skulls. The study addresses the transcranial targeting involved in ultrasound- induced blood-brain barrier (BBB) opening with clinically relevant targets such as the hippocampus and the basal ganglia, which are typically affected by early Alzheimer's and Parkinson's disease, respectively. A finite-difference, timedomain simulation platform is used to solve the 3-D linear acoustic wave equation with CT-based acoustic maps of the skulls. The targeted brain structures were extracted from 3-D brain atlases registered with the skulls and used to virtually position and orient the transducers. The effect of frequency is first investigated and the targeting of the different structures is then tested. The frequency of 500 kHz provided the best tradeoff between phase aberrations and standing wave effects in the human case, whereas the frequency of 800 kHz was most suitable in the case of the primate skull. A fast periodic linear chirp method was developed and found capable of reducing the standing wave effects. Such a simple, affordable, and convenient system is concluded to be feasible for BBB opening in primates and humans and could thus allow for its broader impact and applications.
Collapse
Affiliation(s)
- Thomas Deffieux
- Department of Biomedical Engineering, Columbia, University, New York, NY
| | - Elisa E. Konofagou
- Department of Biomedical Engineering, Columbia, University, New York, NY
- E. E. Konofagou is also with the Department of Radiology, Columbia, University, New York, NY
| |
Collapse
|
91
|
Radiosurgical Induced Neoplasia: A Seldom Seen Complication. World Neurosurg 2010; 73:644-5. [DOI: 10.1016/j.wneu.2010.05.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Indexed: 11/19/2022]
|
92
|
Hertzberg Y, Volovick A, Zur Y, Medan Y, Vitek S, Navon G. Ultrasound focusing using magnetic resonance acoustic radiation force imaging: Application to ultrasound transcranial therapy. Med Phys 2010; 37:2934-42. [DOI: 10.1118/1.3395553] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
93
|
Martin E, Jeanmonod D, Morel A, Zadicario E, Werner B. High-intensity focused ultrasound for noninvasive functional neurosurgery. Ann Neurol 2010; 66:858-61. [PMID: 20033983 DOI: 10.1002/ana.21801] [Citation(s) in RCA: 331] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Transcranial magnetic resonance (MR)-guided high-intensity focused ultrasound (tcMRgHIFU) implies a novel, noninvasive treatment strategy for various brain diseases. Nine patients with chronic neuropathic pain were treated with selective medial thalamotomies. Precisely located thermal ablations of 4mm in diameter were produced at peak temperatures of 51 degrees C to 60 degrees C under continuous visual MR guidance and MR thermometry. The resulting lesions are clearly visible on follow-up MR imaging. All treatments were well tolerated, without side effects or neurological deficits. This is the first report on successful clinical application of tcMRgHIFU in functional brain disorders, portraying it as safe and reliable for noninvasive neurosurgical interventions.
Collapse
Affiliation(s)
- Ernst Martin
- MR-Center, University Children's Hospital Zurich, Zurich, Switzerland.
| | | | | | | | | |
Collapse
|
94
|
Damianou C, Ioannides K, Hadjisavvas V, Mylonas N, Couppis A, Iosif D. In vitro and in vivo brain ablation created by high-intensity focused ultrasound and monitored by MRI. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2009; 56:1189-1198. [PMID: 19574126 DOI: 10.1109/tuffc.2009.1160] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In this paper, magnetic resonance imaging (MRI) is investigated for monitoring small and large lesions created by high-intensity focused ultrasound (HIFU) in freshly excised lamb brain and in rabbit brain in vivo. A single-element spherically focused transducer of 5 cm diameter, focusing at 10 cm and operating at 1 MHz was used. A prototype MRI-compatible positioning device that is used to navigate the transducer is described. The effects of HIFU were investigated using T1-W and T2-W fast spin echo (FSE) and fluid-attenuated inversion recovery (FLAIR). T2-W FSE and FLAIR show better anatomical details within the brain than T1-W FSE, but with T1-W FSE, the contrast between lesion and brain is higher for both thermal and bubbly lesions. The best contrast between lesion and brain with T1-W FSE is obtained with TR above 500 ms, whereas with T2-W FSE, the best contrast is observed between 40 and 60 ms. The maximum contrast to noise ratio (CNR) measured with T1-W FSE was approximately 20. With T2-W FSE, the corresponding CNR was approximately 12. With this system, we were able to create large lesions (by producing overlapping lesions), and it was possible to monitor these lesions with MRI with excellent contrast. The length of the lesions in vivo brain was much higher than the length in vitro, indicating that the penetration in the in vitro brain is limited, possibly by reflection due to trapped bubbles in the blood vessels. This paper demonstrates that HIFU has the potential to treat brain tumors in humans. This could be done either using a single-element transducer with a frequency around 1 MHZ or using a multi-element transducer.
Collapse
|