201
|
Busse H, Schmitgen A, Trantakis C, Schober R, Kahn T, Moche M. Advanced approach for intraoperative MRI guidance and potential benefit for neurosurgical applications. J Magn Reson Imaging 2006; 24:140-51. [PMID: 16739122 DOI: 10.1002/jmri.20597] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To present an advanced approach for intraoperative image guidance in an open 0.5 T MRI and to evaluate its effectiveness for neurosurgical interventions by comparison with a dynamic scan-guided localization technique. MATERIALS AND METHODS The built-in scan guidance mode relied on successive interactive MRI scans. The additional advanced mode provided real-time navigation based on reformatted high-quality, intraoperatively acquired MR reference data, allowed multimodal image fusion, and used the successive scans of the built-in mode for quick verification of the position only. Analysis involved tumor resections and biopsies in either scan guidance (N = 36) or advanced mode (N = 59) by the same three neurosurgeons. Technical, surgical, and workflow aspects were compared. RESULTS The image quality and hand-eye coordination of the advanced approach were improved. While the average extent of resection, neurologic outcome after functional MRI (fMRI) integration, and diagnostic yield appeared to be slightly better under advanced guidance, particularly for the main surgeon, statistical analysis revealed no significant differences. Resection times were comparable, while biopsies took around 30 minutes longer. CONCLUSION The presented approach is safe and provides more detailed images and higher navigation speed at the expense of actuality. The surgical outcome achieved with advanced guidance is (at least) as good as that obtained with dynamic scan guidance.
Collapse
Affiliation(s)
- Harald Busse
- Department of Diagnostic and Interventional Radiology, Leipzig University Hospital, Leipzig, Germany.
| | | | | | | | | | | |
Collapse
|
202
|
Dimaio SP, Archip N, Hata N, Talos IF, Warfield SK, Majumdar A, Mcdannold N, Hynynen K, Morrison PR, Wells WM, Kacher DF, Ellis RE, Golby AJ, Black PM, Jolesz FA, Kikinis R. Image-guided neurosurgery at Brigham and Women's Hospital. IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE : THE QUARTERLY MAGAZINE OF THE ENGINEERING IN MEDICINE & BIOLOGY SOCIETY 2006; 25:67-73. [PMID: 17020201 DOI: 10.1109/memb.2006.1705749] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Simon P Dimaio
- Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
203
|
Schwarzmaier HJ, Eickmeyer F, von Tempelhoff W, Fiedler VU, Niehoff H, Ulrich SD, Yang Q, Ulrich F. MR-guided laser-induced interstitial thermotherapy of recurrent glioblastoma multiforme: preliminary results in 16 patients. Eur J Radiol 2006; 59:208-15. [PMID: 16854549 DOI: 10.1016/j.ejrad.2006.05.010] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2006] [Accepted: 05/18/2006] [Indexed: 11/25/2022]
Abstract
We investigated the survival after laser-induced interstitial thermotherapy in 16 patients suffering from recurrent glioblastoma multiforme. The concept underlying the intervention is the cytoreduction of the tumor tissue by local thermocoagulation. All patients received standard chemotherapy (temozolomide). The median overall survival time after the first relapse was 9.4 months, corresponding to a median overall survival time after laser irradiation of 6.9 months. During the study, however, the median survival after laser coagulation increased to 11.2 months. This survival time is substantially longer than those reported for the natural history (<5 months) or after chemotherapy (temozolomide: 5.4-7.1 months). We conclude that cytoreduction by laser irradiation might be a promising option for patients suffering from recurrent glioblastoma multiforme. In addition, the data indicate the presence of a substantial learning curve. Future work should optimize the therapeutic regimen and evaluate this treatment approach in controlled clinical trials.
Collapse
Affiliation(s)
- Hans-Joachim Schwarzmaier
- Center for Medical Research, Klinikum Krefeld, University of Düsseldorf Medical School at Krefeld, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
204
|
Yushkevich PA, Piven J, Hazlett HC, Smith RG, Ho S, Gee JC, Gerig G. User-guided 3D active contour segmentation of anatomical structures: Significantly improved efficiency and reliability. Neuroimage 2006. [DOI: 10.1016/j.neuroimage.2006.01.015 order by 8029-- #] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
|
205
|
Yushkevich PA, Piven J, Hazlett HC, Smith RG, Ho S, Gee JC, Gerig G. User-guided 3D active contour segmentation of anatomical structures: Significantly improved efficiency and reliability. Neuroimage 2006. [DOI: 10.1016/j.neuroimage.2006.01.015 order by 1-- #] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
|
206
|
Yushkevich PA, Piven J, Hazlett HC, Smith RG, Ho S, Gee JC, Gerig G. User-guided 3D active contour segmentation of anatomical structures: Significantly improved efficiency and reliability. Neuroimage 2006. [DOI: 10.1016/j.neuroimage.2006.01.015 and 1880=1880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
|
207
|
User-guided 3D active contour segmentation of anatomical structures: Significantly improved efficiency and reliability. Neuroimage 2006. [DOI: 10.1016/j.neuroimage.2006.01.015 order by 8029-- -] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
|
208
|
Yushkevich PA, Piven J, Hazlett HC, Smith RG, Ho S, Gee JC, Gerig G. User-guided 3D active contour segmentation of anatomical structures: Significantly improved efficiency and reliability. Neuroimage 2006. [DOI: 10.1016/j.neuroimage.2006.01.015 order by 1-- -] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
|
209
|
Mewes AUJ, Hüppi PS, Als H, Rybicki FJ, Inder TE, McAnulty GB, Mulkern RV, Robertson RL, Rivkin MJ, Warfield SK. Regional brain development in serial magnetic resonance imaging of low-risk preterm infants. Pediatrics 2006; 118:23-33. [PMID: 16818545 DOI: 10.1542/peds.2005-2675] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE MRI studies have shown that preterm infants with brain injury have altered brain tissue volumes. Investigation of preterm infants without brain injury offers the opportunity to define the influence of early birth on brain development and provide normative data to assess effects of adverse conditions on the preterm brain. In this study, we investigated serial MRI of low-risk preterm infants with the aim to identify regions of altered brain development. METHODS Twenty-three preterm infants appropriate for gestational age without magnetic resonance-visible brain injury underwent MRI twice at 32 and at 42 weeks' postmenstrual age. Fifteen term infants were scanned 2 weeks after birth. Brain tissue classification and parcellation were conducted to allow comparison of regional brain tissue volumes. Longitudinal brain growth was assessed from preterm infants' serial scans. RESULTS At 42 weeks' postmenstrual age, gray matter volumes were not different between preterm and term infants. Myelinated white matter was decreased, as were unmyelinated white matter volumes in the region including the central gyri. The gray matter proportion of the brain parenchyma constituted 30% and 37% at 32 and 42 weeks' postmenstrual age, respectively. CONCLUSIONS This MRI study of preterm infants appropriate for gestational age and without brain injury establishes the influence of early birth on brain development. No decreased cortical gray matter volumes were found, which is in contrast to findings in preterm infants with brain injury. Moderately decreased white matter volumes suggest an adverse influence of early birth on white matter development. We identified a sharp increase in cortical gray matter volume in preterm infants' serial data, which may correspond to a critical period for cortical development.
Collapse
Affiliation(s)
- Andrea U J Mewes
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St, Boston, Massachusetts 02115, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
210
|
Yushkevich PA, Piven J, Hazlett HC, Smith RG, Ho S, Gee JC, Gerig G. User-guided 3D active contour segmentation of anatomical structures: Significantly improved efficiency and reliability. Neuroimage 2006. [DOI: 10.1016/j.neuroimage.2006.01.015 order by 1-- gadu] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
|
211
|
User-guided 3D active contour segmentation of anatomical structures: Significantly improved efficiency and reliability. Neuroimage 2006. [DOI: 10.1016/j.neuroimage.2006.01.015 order by 8029-- awyx] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
|
212
|
Abstract
Contemporary imaging modalities can now provide the surgeon with high quality three- and four-dimensional images depicting not only normal anatomy and pathology, but also vascularity and function. A key component of image-guided surgery (IGS) is the ability to register multi-modal pre-operative images to each other and to the patient. The other important component of IGS is the ability to track instruments in real time during the procedure and to display them as part of a realistic model of the operative volume. Stereoscopic, virtual- and augmented-reality techniques have been implemented to enhance the visualization and guidance process. For the most part, IGS relies on the assumption that the pre-operatively acquired images used to guide the surgery accurately represent the morphology of the tissue during the procedure. This assumption may not necessarily be valid, and so intra-operative real-time imaging using interventional MRI, ultrasound, video and electrophysiological recordings are often employed to ameliorate this situation. Although IGS is now in extensive routine clinical use in neurosurgery and is gaining ground in other surgical disciplines, there remain many drawbacks that must be overcome before it can be employed in more general minimally-invasive procedures. This review overviews the roots of IGS in neurosurgery, provides examples of its use outside the brain, discusses the infrastructure required for successful implementation of IGS approaches and outlines the challenges that must be overcome for IGS to advance further.
Collapse
Affiliation(s)
- Terry M Peters
- Robarts Research Institute, University of Western Ontario, PO Box 5015, 100 Perth Drive, London, ON N6A 5K8, Canada.
| |
Collapse
|
213
|
Talos IF, Zou KH, Ohno-Machado L, Bhagwat JG, Kikinis R, Black PM, Jolesz FA. Supratentorial low-grade glioma resectability: statistical predictive analysis based on anatomic MR features and tumor characteristics. Radiology 2006; 239:506-13. [PMID: 16641355 PMCID: PMC1475754 DOI: 10.1148/radiol.2392050661] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To retrospectively assess the main variables that affect the complete magnetic resonance (MR) imaging-guided resection of supratentorial low-grade gliomas. MATERIALS AND METHODS Institutional review board approval was obtained for this retrospective HIPAA-compliant study, with the requirement for informed consent waived. Data from 101 patients (61 men, 40 women; mean age, 39 years; age range, 18-72 years) who had nonenhancing supratentorial mass lesions that were histopathologically diagnosed as low-grade (World Health Organization grade II) gliomas and consecutively underwent surgery with intraoperative MR imaging guidance were analyzed. There were 21 low-grade astrocytomas, 64 oligodendrogliomas, and 16 mixed oligoastrocytomas. Initial and residual tumor volumes were measured on intraoperative T2-weighted MR images and three-dimensional spoiled gradient-echo MR images. The anatomic relationships between the tumor and eloquent cortical and/or subcortical regions and the influence of these relationships on the extent of resection were analyzed on the basis of preoperative MR imaging findings. Summary measures, univariate Fisher exact test and t test, and multivariate logistic regression analyses were performed. RESULTS Tumor volume ranged from 2.7-231.0 mL. Univariate analyses revealed the following tumor characteristics to be significant predictive variables of incomplete tumor resection: diffuse tumor margin on T2-weighted MR images, oligodendroglioma or oligoastrocytoma histopathologic type, and large tumor volume (P < .05 for all). Tumor involvement of the following structures was associated with incomplete resection: corpus callosum, corticospinal tract, insular lobe, middle cerebral artery, motor cortex, optic radiation, visual cortex, and basal ganglia (P < .05 for all). Multivariate analyses revealed that incomplete tumor resection was due to tumor involvement of the corticospinal tract (P < .01), large tumor volume (P < .01), and oligodendroglioma histopathologic type (P = .02). CONCLUSION The main variables associated with incomplete tumor resection in 101 patients were identified by using statistical predictive analyses.
Collapse
|
214
|
Hirai N, Kosaka A, Kawamata T, Hori T, Iseki H. Image-guided neurosurgery system integrating AR-based navigation and open-MRI monitoring. ACTA ACUST UNITED AC 2006; 10:59-71. [PMID: 16298917 DOI: 10.3109/10929080500229389] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
As endoscopic surgery has become a popular form of minimally invasive surgery, it increasingly requires useful imaging tools to help the surgeons perform safe and secure operations. Our navigation system provides surgeons with visual information by overlaying 3D wire frame models of tumor onto live images, as well as by displaying relative the positions of surgical tools and the target tumor. Such 3D wire frame models are generated from pre-operative CT/MR images with the help of a 3D surgical simulation software. Another important function of our system is real-time volume rendering of intra-operative MR images for the target tumor. This function allows surgeons to carefully observe the vicinity of the tumor regions to be removed, by rendering the sectional views with respect to the surgical tool position, so that surgical performance can be easily monitored during the operation. We tested this navigation system in more than 10 clinical operations and verified the effectiveness of the navigation and surgical performance.
Collapse
Affiliation(s)
- Nobuyuki Hirai
- Institute of Advanced Biomedical Engineering and Science, Graduate School of Medicine, Tokyo Women's Medical University, Japan.
| | | | | | | | | |
Collapse
|
215
|
Yushkevich PA, Piven J, Hazlett HC, Smith RG, Ho S, Gee JC, Gerig G. User-guided 3D active contour segmentation of anatomical structures: significantly improved efficiency and reliability. Neuroimage 2006; 31:1116-28. [PMID: 16545965 DOI: 10.1016/j.neuroimage.2006.01.015] [Citation(s) in RCA: 5283] [Impact Index Per Article: 293.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2005] [Revised: 12/21/2005] [Accepted: 01/24/2006] [Indexed: 02/07/2023] Open
Abstract
Active contour segmentation and its robust implementation using level set methods are well-established theoretical approaches that have been studied thoroughly in the image analysis literature. Despite the existence of these powerful segmentation methods, the needs of clinical research continue to be fulfilled, to a large extent, using slice-by-slice manual tracing. To bridge the gap between methodological advances and clinical routine, we developed an open source application called ITK-SNAP, which is intended to make level set segmentation easily accessible to a wide range of users, including those with little or no mathematical expertise. This paper describes the methods and software engineering philosophy behind this new tool and provides the results of validation experiments performed in the context of an ongoing child autism neuroimaging study. The validation establishes SNAP intrarater and interrater reliability and overlap error statistics for the caudate nucleus and finds that SNAP is a highly reliable and efficient alternative to manual tracing. Analogous results for lateral ventricle segmentation are provided.
Collapse
Affiliation(s)
- Paul A Yushkevich
- Penn Image Computing and Science Laboratory, Department of Radiology, University of Pennsylvania, PA 19104-6274, USA.
| | | | | | | | | | | | | |
Collapse
|
216
|
Verhey JF, Nathan NS, Rienhoff O, Kikinis R, Rakebrandt F, D'Ambra MN. Finite-element-method (FEM) model generation of time-resolved 3D echocardiographic geometry data for mitral-valve volumetry. Biomed Eng Online 2006; 5:17. [PMID: 16512925 PMCID: PMC1421418 DOI: 10.1186/1475-925x-5-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2005] [Accepted: 03/03/2006] [Indexed: 11/10/2022] Open
Abstract
Introduction Mitral Valve (MV) 3D structural data can be easily obtained using standard transesophageal echocardiography (TEE) devices but quantitative pre- and intraoperative volume analysis of the MV is presently not feasible in the cardiac operation room (OR). Finite element method (FEM) modelling is necessary to carry out precise and individual volume analysis and in the future will form the basis for simulation of cardiac interventions. Method With the present retrospective pilot study we describe a method to transfer MV geometric data to 3D Slicer 2 software, an open-source medical visualization and analysis software package. A newly developed software program (ROIExtract) allowed selection of a region-of-interest (ROI) from the TEE data and data transformation for use in 3D Slicer. FEM models for quantitative volumetric studies were generated. Results ROI selection permitted the visualization and calculations required to create a sequence of volume rendered models of the MV allowing time-based visualization of regional deformation. Quantitation of tissue volume, especially important in myxomatous degeneration can be carried out. Rendered volumes are shown in 3D as well as in time-resolved 4D animations. Conclusion The visualization of the segmented MV may significantly enhance clinical interpretation. This method provides an infrastructure for the study of image guided assessment of clinical findings and surgical planning. For complete pre- and intraoperative 3D MV FEM analysis, three input elements are necessary: 1. time-gated, reality-based structural information, 2. continuous MV pressure and 3. instantaneous tissue elastance. The present process makes the first of these elements available. Volume defect analysis is essential to fully understand functional and geometrical dysfunction of but not limited to the valve. 3D Slicer was used for semi-automatic valve border detection and volume-rendering of clinical 3D echocardiographic data. FEM based models were also calculated. Method A Philips/HP Sonos 5500 ultrasound device stores volume data as time-resolved 4D volume data sets. Data sets for three subjects were used. Since 3D Slicer does not process time-resolved data sets, we employed a standard movie maker to animate the individual time-based models and visualizations. Calculation time and model size were minimized. Pressures were also easily available. We speculate that calculation of instantaneous elastance may be possible using instantaneous pressure values and tissue deformation data derived from the animated FEM.
Collapse
Affiliation(s)
- Janko F Verhey
- MVIP ImagingProducts GmbH, Nörten-Hardenberg, Germany
- Department of Medical Informatics, University Hospital Göttingen, Göttingen, Germany
| | - Nadia S Nathan
- Department of Anesthesiology, Ohio State University, Columbus, Ohio, USA
| | - Otto Rienhoff
- Department of Medical Informatics, University Hospital Göttingen, Göttingen, Germany
| | - Ron Kikinis
- Surgical Planning Laboratory, Department of Radiology, Brigham and Women's Hospital, Boston, USA
| | - Fabian Rakebrandt
- Department of Medical Informatics, University Hospital Göttingen, Göttingen, Germany
| | - Michael N D'Ambra
- Department of Anesthesiology, Brigham and Women's Hospital, Boston, USA
| |
Collapse
|
217
|
Schwarzmaier HJ, Eickmeyer F, von Tempelhoff W, Fiedler VU, Niehoff H, Ulrich SD, Ulrich F. MR-guided laser irradiation of recurrent glioblastomas. J Magn Reson Imaging 2006; 22:799-803. [PMID: 16270287 DOI: 10.1002/jmri.20446] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
We treated two patients with recurrent glioblastoma multiforme using Nd:YAG laser irradiation in the framework of a salvage therapy. The underlying concept is to achieve cytoreduction by partial coagulation of the tumor. Magnetic resonance imaging (MRI) follow-up examinations revealed a volume reduction of the laser-irradiated areas, while the untreated parts of the tumor exhibited a progression. The survival time after the diagnosis of the recurrence was 16 and 20 months, respectively, which is substantially (about four times) longer than the natural history of the disease would suggest. In conclusion, cytoreduction by laser irradiation may be a promising option for patients suffering from recurrent glioblastoma multiforme. Future work should optimize the therapeutic regimen and evaluate this treatment approach in controlled clinical trials.
Collapse
Affiliation(s)
- Hans-Joachim Schwarzmaier
- Department of Medical Technology, Klinikum Krefeld, University of Düsseldorf Medical School, Krefeld, Germany.
| | | | | | | | | | | | | |
Collapse
|
218
|
Wacker FK, Vogt S, Khamene A, Jesberger JA, Nour SG, Elgort DR, Sauer F, Duerk JL, Lewin JS. An Augmented Reality System for MR Image–guided Needle Biopsy: Initial Results in a Swine Model. Radiology 2006; 238:497-504. [PMID: 16436814 DOI: 10.1148/radiol.2382041441] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To evaluate an augmented reality (AR) system in combination with a 1.5-T closed-bore magnetic resonance (MR) imager as a navigation tool for needle biopsies. MATERIALS AND METHODS The experimental protocol had institutional animal care and use committee approval. Seventy biopsies were performed in phantoms by using 20 tube targets, each with a diameter of 6 mm, and 50 virtual targets. The position of the needle tip in AR and MR space was compared in multiple imaging planes, and virtual and real needle tip localization errors were calculated. Ten AR-guided biopsies were performed in three pigs, and the duration of each procedure was determined. After successful puncture, the distance to the target was measured on MR images. The confidence limits for the achieved in-plane hit rate and for lateral deviation were calculated. A repeated measures analysis of variance was used to determine whether the placement error in a particular dimension (x, y, or z) differed from the others. RESULTS For the 50 virtual targets, a mean error of 1.1 mm +/- 0.5 (standard deviation) was calculated. A repeated measures analysis of variance indicated no statistically significant difference (P > .99) in the errors in any particular orientation. For the real targets, all punctures were inside the 6-mm-diameter tube in the transverse plane. The needle depth was within the target plane in 11 biopsy procedures; the mean distance to the center of the target was 2.55 mm (95% confidence interval: 1.77 mm, 3.34 mm). For nine biopsy procedures, the needle tip was outside the target plane, with a mean distance to the edge of the target plane of 1.5 mm (range, 0.07-3.46 mm). In the animal experiments, the puncture was successful in all 10 cases, with a mean target-needle distance of 9.6 mm +/- 4.85. The average procedure time was 18 minutes per puncture. CONCLUSION Biopsy procedures performed with a combination of a closed-bore MR system and an AR system are feasible and accurate.
Collapse
Affiliation(s)
- Frank K Wacker
- Department of Radiology, University Hospitals of Cleveland, Case Western Reserve University, Cleveland, Ohio, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
219
|
Zou KH, Greve DN, Wang M, Pieper SD, Warfield SK, White NS, Manandhar S, Brown GG, Vangel MG, Kikinis R, Wells WM. Reproducibility of functional MR imaging: preliminary results of prospective multi-institutional study performed by Biomedical Informatics Research Network. Radiology 2006; 237:781-9. [PMID: 16304101 PMCID: PMC1351264 DOI: 10.1148/radiol.2373041630] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To prospectively investigate the factors--including subject, brain hemisphere, study site, field strength, imaging unit vendor, imaging run, and examination visit--affecting the reproducibility of functional magnetic resonance (MR) imaging activations based on a repeated sensory-motor (SM) task. MATERIALS AND METHODS The institutional review boards of all participating sites approved this HIPAA-compliant study. All subjects gave informed consent. Functional MR imaging data were repeatedly acquired from five healthy men aged 20-29 years who performed the same SM task at 10 sites. Five 1.5-T MR imaging units, four 3.0-T units, and one 4.0-T unit were used. The subjects performed bilateral finger tapping on button boxes with a 3-Hz audio cue and a reversing checkerboard. In a block design, 15-second epochs of alternating baseline and tasks yielded 85 acquisitions per run. Functional MR images were acquired with block-design echo-planar or spiral gradient-echo sequences. Brain activation maps standardized in a unit-sphere for the left and right hemispheres of each subject were constructed. Areas under the receiver operating characteristic curve, intraclass correlation coefficients, multiple regression analysis, and paired Student t tests were used for statistical analyses. RESULTS Significant factors were subject (P < .005), k-space (P < .005), and field strength (P = .02) for sensitivity and subject (P = .03) and k-space (P = .05) for specificity. At 1.5-T MR imaging, mean sensitivities ranged from 7% to 32% and mean specificities were higher than 99%. At 3.0 T, mean sensitivities and specificities ranged from 42% to 85% and from 96% to 99%, respectively. At 4.0 T, mean sensitivities and specificities ranged from 41% to 73% and from 95% to 99%, respectively. Mean areas under the receiver operating characteristic curve (+/- their standard errors) were 0.77 +/- 0.05 at 1.5 T, 0.90 +/- 0.09 at 3.0 T, and 0.95 +/- 0.02 at 4.0 T, with significant differences between the 1.5- and 3.0-T examinations and between the 1.5- and 4.0-T examinations (P < .01 for both comparisons). Intraclass correlation coefficients ranged from 0.49 to 0.71. CONCLUSION MR imaging at 3.0- and 4.0-T yielded higher reproducibility across sites and significantly better results than 1.5-T imaging. The effects of subject, k-space, and field strength on examination reproducibility were significant.
Collapse
Affiliation(s)
- Kelly H Zou
- Surgical Planning Laboratory, Dept of Radiology, Brigham and Women's Hosp, Harvard Medical School, Boston, MA 02115, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
220
|
Albu AB. Vision-Based User Interfaces for Health Applications: A Survey. ADVANCES IN VISUAL COMPUTING 2006. [DOI: 10.1007/11919476_77] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
221
|
Tokuda J, Morikawa S, Haque HA, Tsukamoto T, Matsumiya K, Liao H, Masamune K, Dohi T. New 4-D imaging for real-time intraoperative MRI: adaptive 4-D scan. MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION : MICCAI ... INTERNATIONAL CONFERENCE ON MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION 2006; 9:454-61. [PMID: 17354922 DOI: 10.1007/11866565_56] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Aiming at real-time 3-D visualization of organ motion to navigate surgical procedures in MRI-guided surgery, a new 4-D MR imaging technique called "Adaptive 4-D Scan" has been proposed. The technique is designed to acquire a time series of volumetric 3-D images (4-D image) of cyclically moving organ, even in a low-field open-configuration MR scanner. A pre-operative 4-D image is acquired with respiratory phase parameter, which is monitored by using navigator-echo-based real-time tracking of the liver and diaphragm. During operation, the respiratory phase is again monitored in real-time, and a 3-D image, reflecting the current state of the target organ, is extracted from the pre-operative 4-D image and provided to physicians as a pseudo real-time 3-D image. We implemented Adaptive 4-D Scan into a 0.5 Tesla open-configuration clinical MRI system for intervention. Phantom and volunteer studies were performed to assess feasibility of this technique, in terms of image quality, imaging time and position accuracy of the imaged subject. A 4-D image (matrix: 256 x 128 x 10 x 8) of cyclically moving phantom was acquired in 719 s, and RMS position error between the imaged subject and the real subject was 2.3 mm, where the range of motion was 50 mm. 4-D image of the moving liver was also successfully acquired under near clinical condition. In conclusion, the study shows that the proposed method is feasible and has capability to provide real-time dynamic 3-D atlas for surgical navigation.
Collapse
Affiliation(s)
- Junichi Tokuda
- Graduate School of Information Science and Technology, The University of Tokyo, 7-3-1, Hongo, Bunkyo, Tokyo 113-8656, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
222
|
Xie K, Yang J, Zhang ZG, Zhu YM. Semi-automated brain tumor and edema segmentation using MRI. Eur J Radiol 2005; 56:12-9. [PMID: 16168259 DOI: 10.1016/j.ejrad.2005.03.028] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2004] [Revised: 02/25/2005] [Accepted: 03/14/2005] [Indexed: 11/25/2022]
Abstract
PURPOSE Manual segmentation of brain tumors from magnetic resonance images is a challenging and time-consuming task. A semi-automated method has been developed for brain tumor and edema segmentation that will provide objective, reproducible segmentations that are close to the manual results. Additionally, the method segments non-enhancing brain tumor and edema from healthy tissues in magnetic resonance images. METHODS AND MATERIALS In this study, a semi-automated method was developed for brain tumor and edema segmentation and volume measurement using magnetic resonance imaging (MRI). Some novel algorithms for tumor segmentation from MRI were integrated in this medical diagnosis system. We exploit a hybrid level set (HLS) segmentation method driven by region and boundary information simultaneously, region information serves as a propagation force which is robust and boundary information serves as a stopping functional which is accurate. Ten different patients with brain tumors of different size, shape and location were selected, a total of 246 axial tumor-containing slices obtained from 10 patients were used to evaluate the effectiveness of segmentation methods. RESULTS This method was applied to 10 non-enhancing brain tumors and satisfactory results were achieved. Two quantitative measures for tumor segmentation quality estimation, namely, correspondence ratio (CR) and percent matching (PM), were performed. For the segmentation of brain tumor, the volume total PM varies from 79.12 to 93.25% with the mean of 85.67+/-4.38% while the volume total CR varies from 0.74 to 0.91 with the mean of 0.84+/-0.07. For the segmentation of edema, the volume total PM varies from 72.86 to 87.29% with the mean of 79.54+/-4.18% while the volume total CR varies from 0.69 to 0.85 with the mean of 0.79+/-0.08. The HLS segmentation method perform better than the classical level sets (LS) segmentation method in PM and CR. CONCLUSIONS The results of this research may have potential applications, both as a staging procedure and a method of evaluating tumor response during treatment, this method can be used as a clinical image analysis tool for doctors or radiologists.
Collapse
Affiliation(s)
- Kai Xie
- Institute of Image Processing & Pattern Recognition, Shanghai Jiaotong University, 200030 Shanghai, China.
| | | | | | | |
Collapse
|
223
|
Zou KH, Resnic FS, Talos IF, Goldberg-Zimring D, Bhagwat JG, Haker SJ, Kikinis R, Jolesz FA, Ohno-Machado L. A global goodness-of-fit test for receiver operating characteristic curve analysis via the bootstrap method. J Biomed Inform 2005; 38:395-403. [PMID: 16198998 DOI: 10.1016/j.jbi.2005.02.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2004] [Revised: 12/23/2004] [Accepted: 02/22/2005] [Indexed: 11/17/2022]
Abstract
OBJECTIVE Medical classification accuracy studies often yield continuous data based on predictive models for treatment outcomes. A popular method for evaluating the performance of diagnostic tests is the receiver operating characteristic (ROC) curve analysis. The main objective was to develop a global statistical hypothesis test for assessing the goodness-of-fit (GOF) for parametric ROC curves via the bootstrap. DESIGN A simple log (or logit) and a more flexible Box-Cox normality transformations were applied to untransformed or transformed data from two clinical studies to predict complications following percutaneous coronary interventions (PCIs) and for image-guided neurosurgical resection results predicted by tumor volume, respectively. We compared a non-parametric with a parametric binormal estimate of the underlying ROC curve. To construct such a GOF test, we used the non-parametric and parametric areas under the curve (AUCs) as the metrics, with a resulting p value reported. RESULTS In the interventional cardiology example, logit and Box-Cox transformations of the predictive probabilities led to satisfactory AUCs (AUC=0.888; p=0.78, and AUC=0.888; p=0.73, respectively), while in the brain tumor resection example, log and Box-Cox transformations of the tumor size also led to satisfactory AUCs (AUC=0.898; p=0.61, and AUC=0.899; p=0.42, respectively). In contrast, significant departures from GOF were observed without applying any transformation prior to assuming a binormal model (AUC=0.766; p=0.004, and AUC=0.831; p=0.03), respectively. CONCLUSIONS In both studies the p values suggested that transformations were important to consider before applying any binormal model to estimate the AUC. Our analyses also demonstrated and confirmed the predictive values of different classifiers for determining the interventional complications following PCIs and resection outcomes in image-guided neurosurgery.
Collapse
Affiliation(s)
- Kelly H Zou
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, MIT, MA, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
224
|
Nour SG, Lewin JS. Percutaneous Biopsy from Blinded to MR Guided: An Update on Current Techniques and Applications. Magn Reson Imaging Clin N Am 2005; 13:441-64. [PMID: 16084412 DOI: 10.1016/j.mric.2005.04.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The advent of interventional MR imaging techniques as well as their adoption to guide percutaneous biopsies and aspirations has served as a further step along a series of technical refinements that commenced with the implementation of image-guided approaches for tissue sampling. Nowadays, the practice of and the expectations from these procedures are quite different from those of the blind percutaneous thrusts performed in the late nineteenth and early twentieth centuries. As the field of interventional MR imaging continues to flourish and to attract more radiologists who realize the many opportunities that this technology can offer to their patients, there is a need for a full comprehension of the concepts, techniques, limitations, and cost-effectiveness of MR imaging guidance to present this service to clinical partners in the appropriate setting. Radiologists should also recognize the need for their significant involvement in the technical aspects of MR-guided procedures, because several user-defined parameters and trajectory decisions can alter device visualization in the MR imaging environment and hence affect procedure safety.
Collapse
Affiliation(s)
- Sherif Gamal Nour
- Department of Radiology, University Hospitals of Cleveland, 11100 Euclid Avenue, Cleveland, OH 44106, USA.
| | | |
Collapse
|
225
|
Scholz M, Noack V, Pechlivanis I, Engelhardt M, Fricke B, Linstedt U, Brendel B, Ing D, Schmieder K, Ermert H, Harders A. Vibrography during tumor neurosurgery. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2005; 24:985-92. [PMID: 15972713 DOI: 10.7863/jum.2005.24.7.985] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
OBJECTIVE The aim of this study was to determine whether elastography, a sonographically based real-time strain imaging method for registering the elastic properties of tissue, can be used in brain tumor surgery. METHODS A modification of classic elastography called vibrography was applied in these measurements with static compression replaced by low-frequency axial vibration. Twenty patients were examined with this technique during brain tumor surgery. A conventional sonographic system with a custom-designed radio frequency (RF) interface was used. The RF data were digitized with a 50-MHz, 12-bit peripheral component interconnect analog/digital converter for real-time or offline processing. Sonographic RF data were acquired with a 6.5-MHz endocavity curved array. A special applicator equipped with a stepping motor moved the ultrasonic probe and produced a low-frequency mechanical vibration of approximately 5 to 10 Hz with a vibration amplitude of 0.3 mm. RESULTS Detection of tumors was possible in 18 of 20 cases. Brain tissue was normally color coded orange or red. Three major groups of tumors with different elastic properties relative to brain tissue could be differentiated. In 3 cases, the stiffness of the tumor was identical to that of brain tissue, but the tumors were surrounded by a thin yellow border. Six tumors displayed higher strain than brain, whereas 7 tumors exhibited lower strain than the surrounding cerebrum. Two patients could not be assigned clearly to either of these groups. CONCLUSIONS These findings indicate that vibrography is a feasible imaging method for brain tumor surgery and may have numerous potential applications in neurosurgery if further improvements are made.
Collapse
Affiliation(s)
- Martin Scholz
- Department of Neurosurgery, Ruhr University Bochum, In der Schornau 23-25, 44892 Bochum, Germany.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
226
|
Abe H, Kurumi Y, Naka S, Shiomi H, Umeda T, Naitoh H, Endo Y, Hanasawa K, Morikawa S, Tani T. Open-configuration MR-guided microwave thermocoagulation therapy for metastatic liver tumors from breast cancer. Breast Cancer 2005; 12:26-31. [PMID: 15657520 DOI: 10.2325/jbcs.12.26] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Liver metastases from breast cancer are associated with a poor prognosis, however, local control with microwave thermocoagulation therapy has been used in certain subgroups of these patients in the past decade. In this study, open-configuration magnetic resonance (MR) -guided microwave thermocoagulation therapy was used for metastatic liver tumors from breast cancer, and the efficacy of this treatment was assessed. METHODS Between June 2000 and April 2004, we used MR-guided microwave thermocoagulation therapy on 11 nodules in 8 patients with metastatic liver tumors from breast cancer. The procedure was carried out under general anesthesia. A 0.5 T open-configuration MR system and a microwave coagulator were used. Near-real-time MR images and real-time temperature images were collected and displayed on the monitor. The MR-compatible thoracoscope was used and combined with MR imaging guidance. Navigation software, a 3D Slicer, was installed and customized. RESULTS The customized navigation software displayed near-real-time MR images. The percutaneous puncture into the tumors was successful in all cases. No mortality or major complications occurred as a result of the procedures. Five of the 8 patients are alive with new metastatic foci with a mean observation period of 25.9 months. CONCLUSIONS We developed several devices to allow safe, easy, and accurate MR-guided microwave thermocoagulation therapy of liver tumors. Open-configuration MR-guided microwave thermocoagulation therapy appears to be a feasible method for tumor ablation of metastatic liver tumors from breast cancer.
Collapse
Affiliation(s)
- Hajime Abe
- Division of General Surgery, Department of Surgery, Shiga University of Medical Science, Seta-Tsukinowa, Otsu, Shiga, 520-2192, Japan.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
227
|
Zook JM, Iftekharuddin KM. Statistical analysis of fractal-based brain tumor detection algorithms. Magn Reson Imaging 2005; 23:671-8. [PMID: 16051042 DOI: 10.1016/j.mri.2005.04.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2004] [Accepted: 04/11/2005] [Indexed: 11/21/2022]
Abstract
Fractals are geometric objects that have a noninteger fractal dimension (FD). The FD has been exploited for various biomedical recognition applications such as breast tumor and lung tumor detection. Our previous work shows that the FD is useful in the detection of brain tumors when a reference nontumor image is available. In this work, we extend our previous work by statistically validating the results of FD analysis on a set of 80 real MR and CT images. Our half-image technique requires that the tumor is located in one half of the brain whereas our whole-image technique does not. Furthermore, we alleviate the need for a reference (control) nontumor image to compute the tumor FD, which was necessary in our previous work. We also compare the brain tumor detection performance of our algorithms with other fractal-based algorithms in the literature and statistically validate our results against manually segmented tumor images. We find that the tumor region offers a statistically significant lower FD compared with that of the nontumor area for most of the FD algorithms studied in this work. Thus, our statistical analysis suggests that these FD algorithms may be exploited successfully to determine the possible presence and location of brain tumors in MR and CT images.
Collapse
Affiliation(s)
- Justin M Zook
- Department of Biomedical Engineering, The University of Memphis, TN 38152-3810, USA
| | | |
Collapse
|
228
|
Bartling SH, Peldschus K, Rodt T, Kral F, Matthies H, Kikinis R, Becker H. Registration and Fusion of CT and MRI of the Temporal Bone. J Comput Assist Tomogr 2005; 29:305-10. [PMID: 15891495 DOI: 10.1097/01.rct.0000160425.63884.5b] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To present and evaluate a registration method to fuse complementary information of CT and MRI of the temporal bone. METHODS CT and MRI of the temporal bone of 26 patients were independently registered 4 times. A manual, iterative, intrinsic, rigid, and retrospective registration method was used. Mean CREm (consistency registration error) was calculated as a reproducibility measurement. RESULTS CREm was 0.6 mm (95% CI = 0.52-0.68 mm). T-test revealed no difference between pathologic and normal cases (t[102] = -1.71; P = 0.09). Time needed: 13 minutes. In the registered and fused datasets, important bony surgical landmarks (eg, facial nerve canal, inner ear) could be assessed in 3 dimensions relatively to tumor tissue (eg, acoustic schwannoma). Fluid distribution within partially obliterated cochleae could be assigned to either scalae. CONCLUSION An accurate, reproducible registration and fusion method that improves tumor surgery and cochlea implantation planning with only minor changes to the clinical workflow was presented and described. We suggest this method in selected cases.
Collapse
|
229
|
Schulz T, Tröbs RB, Schneider JP, Hirsch W, Puccini S, Schmidt F, Kahn T. Pediatric MR-guided interventions. Eur J Radiol 2005; 53:57-66. [PMID: 15607853 DOI: 10.1016/j.ejrad.2004.07.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2004] [Revised: 07/20/2004] [Accepted: 07/26/2004] [Indexed: 11/16/2022]
Abstract
MRI guided interventions are a relatively new but steadily growing field within surgery in pediatric age. Besides the advantages of MRI, such as multiplanar capability and excellent soft tissue contrast and spatial resolution, particularly relevant for the pediatric population is the lack of ionizing radiation. There is meanwhile a group of well defined diagnostic or therapeutic indications for applying MR imaging during pediatric interventions. Aim of this review is to give an overview about indications of MR-guided procedures in children as well as the advantages and disadvantages of MR-guided interventions. We also briefly discuss interventional MR-systems and MR-compatible devices. It is our opinion that MR-guidance for pediatric interventions is a promising technique at the beginning of its development.
Collapse
Affiliation(s)
- T Schulz
- University of Leipzig, Department of Diagnostic Radiology, Liebigstrasse 20, 04103 Leipzig, Germany.
| | | | | | | | | | | | | |
Collapse
|
230
|
Strik HM, Borchert H, Fels C, Knauth M, Rienhoff O, Bähr M, Verhey JF. Three-dimensional reconstruction and volumetry of intracranial haemorrhage and its mass effect. Neuroradiology 2005; 47:417-24. [PMID: 15856213 DOI: 10.1007/s00234-005-1373-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2004] [Accepted: 01/10/2005] [Indexed: 10/25/2022]
Abstract
Intracerebral haemorrhage still causes considerable disability and mortality. The studies on conservative and operative management are inconclusive, probably due to inexact volumetry of the haemorrhage. We investigated whether three-dimensional (3-D), voxel-based volumetry of the haemorrhage and its mass effect is feasible with routine computed tomography (CT) scans. The volumes of the haemorrhage, ventricles, midline shift, the intracranial volume and ventricular compression in CT scans of 12 patients with basal ganglia haemorrhage were determined with the 3-D slicer software. Indices of haemorrhage and intracranial or ventricular volume were calculated and correlated with the clinical data. The intended measures could be determined with an acceptable intra-individual variability. The 3-D volumetric data tended to correlate better with the clinical course than the conventionally assessed distance of midline shift and volume of haemorrhage. 3-D volumetry of intracranial haemorrhage and its mass effect is feasible with routine CT examination. Prospective studies should assess its value for clinical studies on intracranial space-occupying diseases.
Collapse
Affiliation(s)
- H M Strik
- Department of Neurology, Medical School, University of Göttingen, Germany.
| | | | | | | | | | | | | |
Collapse
|
231
|
Davison BD, Yeshwant K, Kikinis R, Rolnick J, Zou K, Chung B, Yucel EK. Development and testing of a cross-sectional area measurement tool for evaluating vein size. Comput Biol Med 2005; 35:617-26. [PMID: 15809099 DOI: 10.1016/j.compbiomed.2004.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2003] [Revised: 12/26/2003] [Accepted: 04/05/2004] [Indexed: 10/26/2022]
Abstract
This paper describes a software system for measuring cross-sectional area in reconstructed elliptical tubular structures. A measurement tool was developed using the freely available, cross-platform, open-source three-dimensional (3-D) Slicer environment. The software is easy to operate and allows the user to make multiple measurements on the fly. Results can be displayed to the screen, output to the system printer, and written to a user-specified data file for later analysis in commercial spreadsheet software. Measuring a known cross-sectional area tested the software. Phantoms of known physical dimensions were imaged using both CT and MR. The measured cross-sectional areas reported by the software were compared to each other, and the cross-sectional areas calculated from the known physical dimensions of the phantoms. The measurement errors were negligible. The results of this study indicate that the cross-sectional area measurement tool described provides reliable measurements and is an inexpensive and versatile alternative to high-end 3-D modeling software.
Collapse
Affiliation(s)
- Brian D Davison
- Department of Radiology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA 02115, USA.
| | | | | | | | | | | | | |
Collapse
|
232
|
Zou KH, Tuncali K, Warfield SK, Zentai CP, Worku D, Morrison PR, Silverman SG. Three-dimensional assessment of MR imaging-guided percutaneous cryotherapy using multi-performer repeated segmentations: the value of supervised learning. Acad Radiol 2005; 12:444-50. [PMID: 15831417 DOI: 10.1016/j.acra.2004.11.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2004] [Revised: 12/09/2004] [Accepted: 12/10/2004] [Indexed: 11/30/2022]
Abstract
RATIONALE AND OBJECTIVES Accurate and reproducible segmentations of two-dimensional images are an important prerequisite for assessing tumor ablations three dimensionally (3D). We evaluated whether supervised learning methods would improve multiperformer repeated segmentations of magnetic resonance images (MRI) obtained before and after MRI-guided cryotherapy of renal cell carcinoma. MATERIALS AND METHODS Three medical students independently performed five manual segmentations of a biopsy-proven renal cell carcinoma that was treated with percutaneous MRI-guided cryotherapy. Using pretreatment (T2-weighted fast recovery fast spin echo [FRFSE]) and posttreatment (T1-weighted, fat-suppressed, dynamically enhanced) MRIs, regions of tumor cryonecrosis were segmented. The same tasks were repeated after an experienced abdominal radiologist provided supervised learning. Segmentation sensitivity was compared with an estimated 3D-ground truth via voxel counts for regions of tumor, both before and after treatment, and for the regions of cryonecrosis. The sensitivity of each repeated segmentation was compared against the estimated ground truth using sensitivity, overlap index, and volume (mL). RESULTS Supervised learning significantly improved posttreatment segmentation sensitivity (P = .03). With supervised learning, the ranges of the performance metrics over the segmentation performers were: pretreated tumor, sensitivity 0.902-0.999, overlap index 0.935-0.961, and volume 19.15-23.71 mL; posttreated tumor, sensitivity 0.923-0.991, overlap index 0.952-0.981, and volume 20.67-22.70 mL; in the ablation zone, sensitivity 0.938-0.969, overlap index 0.940-0.962, and volume 31.79-32.36 mL. CONCLUSIONS Supervised learning improved multiperformer repeated segmentations of MRIs obtained before and after MRI-guided percutaneous cryotherapy of renal cell carcinoma. These methods may prove useful in aiding the 3D assessment of percutaneous tumor ablations.
Collapse
Affiliation(s)
- Kelly H Zou
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | | | | | | | | | | | | |
Collapse
|
233
|
Yeshwant K, Seldin EB, Gateno J, Everett P, White CL, Kikinis R, Kaban LB, Troulis MJ. Analysis of skeletal movements in mandibular distraction osteogenesis. J Oral Maxillofac Surg 2005; 63:335-40. [PMID: 15742283 DOI: 10.1016/j.joms.2004.06.057] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE The purpose of this study was to use geometric parameters of movement, calculated from 3-dimensional computed tomography (CT) data, to determine the curvilinear distractor dimensions required to correct mandibular deformities in a series of patients. MATERIALS AND METHODS Preoperative CT scans from 15 patients with symmetric (n = 5) and asymmetric (n = 10) deformities were imported into a CT-based software program (Osteoplan; an open-source visualization application developed by Gering et al at the Surgical Planning Laboratory [SPL, Brigham and Womens Hospital, Boston, MA]). The software was used to reconstruct virtual 3-dimensional models from these scans. Two experienced surgeons, working with a computer scientist, then used Osteoplan to create an ideal treatment plan for each patient. In each case, the 3-dimensional curvilinear movement was quantified using 4 "parameters of movement" (POMs). These parameters were then used to prescribe a distraction device capable of executing the planned skeletal correction. Curvilinear distractor dimensions calculated by Osteoplan included the radius of curvature of the prescribed device, and the distractor elongation, pitch, and handedness. RESULTS Treatment plans including POMs were developed for each patient. The radii of curvature for the prescribed distractors ranged from 2.3 to 14.1 cm, the distractor elongation dimensions ranged from 0.7 to 3.2 cm, and the pitch (horizontal plane) dimensions ranged from 0.005 to 0.8 cm. Handedness was either a left (n = 12) or right (n = 8) turning helix. CONCLUSION The results of this study indicate that, using geometric parameters of movement calculated from 3-dimensional CT scans, curvilinear devices could be prescribed for correction of the range of skeletal deformities in this group of patients.
Collapse
Affiliation(s)
- Krishna Yeshwant
- Department of Oral and Maxillofacial Surgery, Massachusetts General Hospital, Boston 02114, USA
| | | | | | | | | | | | | | | |
Collapse
|
234
|
Abstract
PET imaging with (18)F-2-deoxy-2-fluoro-D-glucose (FDG-PET) is useful both for the initial evaluation of brain tumors and for follow up after therapy. Over 400 FDG-PET studies are performed at Duke University Medical Center annually for brain tumors. Image registration of FDG-PET data with anatomic imaging (MRI) is essential to accurately localize the abnormality in the brain because of the metabolic heterogeneity of brain tumors and the high background metabolism of normal cerebral cortex. A practical semi-automated image registration technique has been developed which is used routinely for all brain tumor patients. In the future, image registration will likely become increasingly important for FDG and other PET tracers used for brain tumor imaging, and the combined functional/anatomic information will be utilized directly for therapeutic radiation and surgical treatment planning.
Collapse
Affiliation(s)
- Terence Z Wong
- Department of Radiology, Nuclear Medicine Division, Duke University Medical Center, Durham, North Carolina 27710, USA.
| | | | | | | |
Collapse
|
235
|
Abstract
MRI-guided neurosurgery not only represents a technical challenge but a transformation from conventional hand-eye coordination to interactive navigational operations. In the future, multimodality-based images will be merged into a single model, in which anatomy and pathologic changes are at once distinguished and integrated into the same intuitive framework. The long-term goals of improving surgical procedures and attendant outcomes, reducing costs, and achieving broad use can be achieved with a three-pronged approach: 1. Improving the presentation of preoperative and real-time intraoperative image information 2. Integrating imaging and treatment-related technology into therapy delivery systems 3. Testing the clinical utility of image guidance in surgery The recent focus in technology development is on improving our ability to understand and apply medical images and imaging systems. Areas of active research include image processing, model-based image analysis, model deformation, real-time registration, real-time 3D (so-called "four-dimensional") imaging, and the integration and presentation of image and sensing information in the operating room. Key elements of the technical matrix also include visualization and display platforms and related software for information and display, model-based image understanding, the use of computing clusters to speed computation (ie, algorithms with partitioned computation to optimize performance), and advanced devices and systems for 3D device tracking (navigation). Current clinical applications are successfully incorporating real-time and/or continuously up-dated image-based information for direct intra-operative visualization. In addition to using traditional imaging systems during surgery, we foresee optimized use of molecular marker technology, direct measures of tissue characterization (ie, optical measurements and/or imaging), and integration of the next generation of surgical and therapy devices (including image-guided robotic systems). Although we expect the primary clinical thrusts of MRI-guided therapy to remain in neurosurgery, with the possible addition of other areas like orthopedic, head, neck, and spine surgery, we also anticipate increased use of image-guided focal thermal ablative methods (eg, laser, RF, cryoablation, high-intensity focused ultrasound). By validating the effectiveness of MRI-guided therapy in specific clinical procedures while refining the technology that serves as its underpinning at the same time, we expect many neurosurgeons will eventually embrace MRI as their intraoperative imaging choice. Clearly, intraoperative MRI offers several palpable advantages. Most important among these are improved medical outcomes, shorter hospitalization, and better and faster procedures with fewer complications. Certain economic and practical barriers also impede the large-scale use of intraoperative MRI. Although there has been a concerted technical effort to increase the benefit/cost ratio by gathering more accurate information, designing more localized and less invasive treatment devices, and developing better methods to orient and position therapy end-effectors, further research is needed. Indeed, the drive to improve and upgrade technology is ongoing. Specifically, in the context of the real-time representation of the patient's anatomy, we have improved the quality and utility of the information presented to the surgeon, which, in turn, contributes to more successful surgical outcomes. We can also expect improvements in intraoperative imaging systems as well as increased use of nonimaging sensors and robotics to facilitate more widespread use of intraoperative MRI.
Collapse
Affiliation(s)
- Ferenc A Jolesz
- Division of MRI and Image Guided Therapy Program, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
| |
Collapse
|
236
|
Hata N, Muragaki Y, Inomata T, Maruyama T, Iseki H, Hori T, Dohi T. Intraoperative tumor segmentation and volume measurement in MRI-guided glioma surgery for tumor resection rate control. Acad Radiol 2005; 12:116-22. [PMID: 15691732 DOI: 10.1016/j.acra.2004.11.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2004] [Revised: 10/20/2004] [Accepted: 11/02/2004] [Indexed: 11/17/2022]
Abstract
RATIONALE AND OBJECTIVES Gross-total surgery under intraoperative magnetic resonance imaging (MRI) is a promising method of glioma removal. The purpose of this article is intraoperative measurement of resected tumor volume in MRI-guided glioma surgery using semiautomatic image segmentation to unbiased resection rate control. MATERIALS AND METHODS A newly developed software program based on a fuzzy connectedness (FC) segmentation algorithm was used to achieve fast and semiautomatic tumor segmentation and tumor volume measurement. The program was validated by retrospective study of eight glioma cases and then applied to seven glioma cases. All clinical cases underwent actual MRI-guided surgery using 0.3-T open magnets. RESULTS The volume of the tumor before resection ranged from 10.1 to 206.7 mL. A comparison of the results of manual segmentation with those of the semiautomatic FC-based segmentation gave an average dice similarity coefficient of 0.80 and an average match of 76%. Volume measurement combined with a developed software program enabled quantitative monitoring of tumor removal, which was critical in the near-total resection of glioma in MRI-guided surgery. CONCLUSION The FC-based tumor segmentation method can be used for intraoperative tumor segmentation and volume measurement in MRI-guided glioma surgery using 0.3-T open magnets. This method is useful for objective resection rate monitoring, which may ultimately minimize the amount of residual tumor in glioma surgery.
Collapse
Affiliation(s)
- Nobuhiko Hata
- Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan.
| | | | | | | | | | | | | |
Collapse
|
237
|
Sato K, Morikawa S, Inubushi T, Kurumi Y, Naka S, Haque HA, Demura K, Tani T. Alternate Biplanar MR Navigation for Microwave Ablation of Liver Tumors. Magn Reson Med Sci 2005; 4:89-94. [PMID: 16340163 DOI: 10.2463/mrms.4.89] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Real-time MR (magnetic resonance) images in two perpendicular planes, both of which included the path of the needle, were utilized for MR-guided microwave ablation of liver tumors. The two image planes were automatically and alternately switched by new MR scanner control software installed on an external PC. This technique is possible only with MRI (magnetic resonance imaging) units with multiplanar and multisection capabilities. Reformatted images in the corresponding two planes were also constructed from preoperative three-dimensional volume data. These four images (two real-time and two reformatted) were continuously visible to the surgeons. These images enabled the needle position in the three-dimensional space to be accurately and clearly recognized, in contrast to the difficulty encountered with two-dimensional MR images in a single image plane. This technique was also applied to MR temperature mapping during microwave ablation, as it allowed monitoring of the spread of the heat in a three-dimensional space. This type of computer-integrated image navigation was demonstrated to be feasible for MR-guided microwave ablation of liver tumors.
Collapse
Affiliation(s)
- Koichiro Sato
- Department of Surgery, Shiga University of Medical Science, Ohtsu, Shiga 520-2192, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
238
|
Claus EB, Horlacher A, Hsu L, Schwartz RB, Dello-Iacono D, Talos F, Jolesz FA, Black PM. Survival rates in patients with low-grade glioma after intraoperative magnetic resonance image guidance. Cancer 2005; 103:1227-33. [PMID: 15690327 DOI: 10.1002/cncr.20867] [Citation(s) in RCA: 318] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND No age-adjusted or histologic-adjusted assessments of the association between extent of resection and risk of either recurrence or death exist for neurosurgical patients who undergo resection of low-grade glioma using intraoperative magnetic resonance image (MRI) guidance. METHODS The current data included 156 patients who underwent surgical resection of a unifocal, supratentorial, low-grade glioma in the MRI suite at Brigham and Women's Hospital between January 1, 1997, and January 31, 2003. Estimates of disease-free and overall survival probabilities were calculated using Kaplan-Meier methodology. The association between extent of resection and these probabilities was measured using a Cox proportional hazards model. Observed death rates were compared with the expected death rate using age-specific and histologic-specific survival rates obtained from the Surveillance, Epidemiology, and End Results Registry. RESULTS Patients who underwent subtotal resection were at 1.4 times the risk of disease recurrence (95% confidence interval [95% CI], 0.7-3.1) and at 4.9 times the risk of death (95% CI, 0.61-40.0) relative to patients who underwent gross total resection. The 1-year, 2-year, and 5-year age-adjusted and histologic-adjusted death rates for patients who underwent surgical resection using intraoperative MRI guidance were 1.9% (95% CI, 0.3-4.2%), 3.6% (95% CI, 0.4-6.7%), and 17.6% (95% CI, 5.9-29.3%), respectively: significantly lower than the rates reported using national data bases. CONCLUSIONS The data from the current study suggested a possible association between surgical resection and survival for neurosurgical patients who underwent surgery for low-grade glioma under intraoperative MRI guidance. Further study within the context of a large, prospective, population-based project will be needed to confirm these findings.
Collapse
Affiliation(s)
- Elizabeth B Claus
- Department of Neurosurgery, Brigham and Women's Hospital, Boston, Massachusetts, USA.
| | | | | | | | | | | | | | | |
Collapse
|
239
|
Warfield SK, Haker SJ, Talos IF, Kemper CA, Weisenfeld N, Mewes AUJ, Goldberg-Zimring D, Zou KH, Westin CF, Wells WM, Tempany CMC, Golby A, Black PM, Jolesz FA, Kikinis R. Capturing intraoperative deformations: research experience at Brigham and Women's Hospital. Med Image Anal 2004; 9:145-62. [PMID: 15721230 DOI: 10.1016/j.media.2004.11.005] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
During neurosurgical procedures the objective of the neurosurgeon is to achieve the resection of as much diseased tissue as possible while achieving the preservation of healthy brain tissue. The restricted capacity of the conventional operating room to enable the surgeon to visualize critical healthy brain structures and tumor margin has lead, over the past decade, to the development of sophisticated intraoperative imaging techniques to enhance visualization. However, both rigid motion due to patient placement and nonrigid deformations occurring as a consequence of the surgical intervention disrupt the correspondence between preoperative data used to plan surgery and the intraoperative configuration of the patient's brain. Similar challenges are faced in other interventional therapies, such as in cryoablation of the liver, or biopsy of the prostate. We have developed algorithms to model the motion of key anatomical structures and system implementations that enable us to estimate the deformation of the critical anatomy from sequences of volumetric images and to prepare updated fused visualizations of preoperative and intraoperative images at a rate compatible with surgical decision making. This paper reviews the experience at Brigham and Women's Hospital through the process of developing and applying novel algorithms for capturing intraoperative deformations in support of image guided therapy.
Collapse
Affiliation(s)
- Simon K Warfield
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
240
|
Hawkes DJ, Barratt D, Blackall JM, Chan C, Edwards PJ, Rhode K, Penney GP, McClelland J, Hill DLG. Tissue deformation and shape models in image-guided interventions: a discussion paper. Med Image Anal 2004; 9:163-75. [PMID: 15721231 DOI: 10.1016/j.media.2004.11.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
This paper promotes the concept of active models in image-guided interventions. We outline the limitations of the rigid body assumption in image-guided interventions and describe how intraoperative imaging provides a rich source of information on spatial location of anatomical structures and therapy devices, allowing a preoperative plan to be updated during an intervention. Soft tissue deformation and variation from an atlas to a particular individual can both be determined using non-rigid registration. Established methods using free-form deformations have a very large number of degrees of freedom. Three examples of deformable models--motion models, biomechanical models and statistical shape models--are used to illustrate how prior information can be used to restrict the number of degrees of freedom of the registration algorithm and thus provide active models for image-guided interventions. We provide preliminary results from applications for each type of model.
Collapse
Affiliation(s)
- D J Hawkes
- Division of Imaging Sciences, GKT School of Medicine, King's College London, UK.
| | | | | | | | | | | | | | | | | |
Collapse
|
241
|
Engström M, Ragnehed M, Lundberg P, Söderfeldt B. Paradigm design of sensory-motor and language tests in clinical fMRI. Neurophysiol Clin 2004; 34:267-77. [PMID: 15890160 DOI: 10.1016/j.neucli.2004.09.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2004] [Accepted: 09/24/2004] [Indexed: 11/17/2022] Open
Abstract
Functional magnetic resonance imaging (fMRI) paradigms on sensory-motor and language functions are reviewed from a clinical user's perspective. The objective was to identify special requirements regarding the design of fMRI paradigms for clinical applications. A wide range of methods for setting up fMRI examinations were found in the literature. It was concluded that there is a need for standardised procedures adapted for clinical settings. Sensory-motor activation patterns do not vary much at different hand motion tasks. Nevertheless it is one of the most important clinical tests. In contrast, the language system is much more complex. In several studies it has been observed that word production tasks are preferable in determination of language lateralisation. Broca's area is activated by most tasks, whereas sentence processing and semantic decision also involve activation in temporoparietal and frontal areas. However, combined task analysis (CTA) of several different tasks has been found to be more robust and reliable for clinical fMRI compared to separate task analysis.
Collapse
Affiliation(s)
- Maria Engström
- Center for Medical Image Science and Visualisation (CMIV), Linköping University/US, 581 85 Linköping, Sweden.
| | | | | | | |
Collapse
|
242
|
McConnell KA, Zou KH, Chabrerie AV, Bailey NO, Black PM. Decreases in ventricular volume correlate with decreases in ventricular pressure in idiopathic normal pressure hydrocephalus patients who experienced clinical improvement after implantation with adjustable valve shunts. Neurosurgery 2004; 55:582-92; discussion 592-3. [PMID: 15335425 PMCID: PMC1350579 DOI: 10.1227/01.neu.0000134385.23401.01] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2003] [Accepted: 04/07/2004] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE This retrospective study examined whether changes in ventricular volume correspond with changes in adjustable valve pressure settings in a cohort of patients who received shunts to treat idiopathic normal pressure hydrocephalus. We also examined whether these pressure-volume curves and other patient variables would co-occur with a positive clinical response to shunting. METHODS We selected 51 patients diagnosed with idiopathic normal pressure hydrocephalus who had undergone implantation of a Codman Hakim programmable valve (Medos S.A., Le Locle, Switzerland). Clinical data were gathered from the patients' records and clinical notes by an investigator blinded to patients' ventricular volumes. Ventricular volume was measured using 3D Slicer, an image analysis and interactive visualization software package developed and maintained at the Surgical Planning Laboratory at Brigham and Women's Hospital. RESULTS Eighty-six percent of patients with gait disturbance at presentation showed improvement of this symptom, 70% experienced improvement in incontinence, and 69% experienced improvement in dementia. For the group showing 100% clinical improvement, the correlation coefficient of average changes in valve pressure over time (delta P/delta T) and average changes in ventricular volume over time (delta V/delta T) were high at 0.843 (P < 0.05). For the group experiencing no or only partial improvement, the correlation coefficient was 0.257 (P = 0.32), indicating no correlation between average delta V/delta T and average delta P/delta T for each patient. CONCLUSION This was a carefully analyzed modeling study of idiopathic normal pressure hydrocephalus treatment made possible only by adjustable valve technology. With careful volumetric analysis, we found that changes in ventricular volume correlated with adjustments in valve pressure settings for those patients who improved clinically after shunting. This suggests that positive clinical responders retained parenchymal elasticity, emphasizing the importance of dynamic changes in this cohort.
Collapse
Affiliation(s)
- Kathleen A McConnell
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | | | | | | | | |
Collapse
|
243
|
Schulz T, Puccini S, Schneider JP, Kahn T. Interventional and intraoperative MR: review and update of techniques and clinical experience. Eur Radiol 2004; 14:2212-27. [PMID: 15480689 DOI: 10.1007/s00330-004-2496-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2004] [Revised: 08/12/2004] [Accepted: 08/16/2004] [Indexed: 11/30/2022]
Abstract
The concept of interventional magnetic resonance imaging (MRI) is based on the integration of diagnostic and therapeutic procedures, favored by the combination of the excellent morphological and functional imaging characteristics of MRI. The spectrum of MRI-assisted interventions ranges from biopsies and intraoperative guidance to thermal ablation modalities and vascular interventions. The most relevant recently published experimental and clinical results are discussed. In the future, interventional MRI is expected to play an important role in interventional radiology, minimal invasive therapy and guidance of surgical procedures. However, the associated high costs require a careful evaluation of its potentials in order to ensure cost-effective medical care.
Collapse
Affiliation(s)
- Thomas Schulz
- Department of Diagnostic Radiology, Leipzig University Hospital, Liebigstrasse 20, 04103 Leipzig, Germany.
| | | | | | | |
Collapse
|
244
|
Silverman SG, Sun MRM, Tuncali K, Morrison PR, vanSonnenberg E, Shankar S, Zou KH, Warfield SK. Three-dimensional assessment of MRI-guided percutaneous cryotherapy of liver metastases. AJR Am J Roentgenol 2004; 183:707-12. [PMID: 15333359 DOI: 10.2214/ajr.183.3.1830707] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE We report our initial investigation of the use of a 3D method for assessing percutaneous tumor ablations. We hypothesized that these 3D techniques could be used to assess the technical success of ablations and that 3D metrics would be predictive of treatment response. CONCLUSION Three-dimensional assessment of percutaneous tumor ablations provides a quantitative evaluation of the technical success of the procedure. Three-dimensional computer-based techniques can both quantify coverage of a tumor and create a virtual ablation margin for percutaneous procedures, akin to a surgical margin. Although results are preliminary, 3D metrics were useful in predicting treatment response.
Collapse
Affiliation(s)
- Stuart G Silverman
- Department of Radiology, Division of Abdominal Imaging and Intervention, Brigham and Women's Hospital, 75 Francis St., Boston, MA 02115, USA.
| | | | | | | | | | | | | | | |
Collapse
|
245
|
Ilkko E, Suomi K, Karttunen A, Tervonen O. Computer-assisted diagnosis by temporal subtraction in postoperative brain tumor patients: a feasibility study. Acad Radiol 2004; 11:887-93. [PMID: 15288039 DOI: 10.1016/j.acra.2004.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2004] [Revised: 01/29/2004] [Accepted: 02/26/2004] [Indexed: 11/17/2022]
Abstract
RATIONALE AND OBJECTIVES To introduce and evaluate a novel, image fusion-based technique that can be used to compare the findings of primary and control brain magnetic resonance imaging scans, with special attention to the differences found in this comparison. MATERIALS AND METHODS A new technique named "colored difference mapping" was applied to the brain examinations of five patients. The possible changes in the magnetic resonance imaging findings were analyzed by the colored difference mapping technique and by using conventional film reading and the results were compared. RESULTS Colored difference mapping accurately depicts the differences between successive magnetic resonance images and reveals small changes that are difficult to perceive in a visual evaluation. CONCLUSION Colored difference mapping is suitable for comparison of images between two different radiologic examinations and helps to show even minimal changes in brain tissues.
Collapse
Affiliation(s)
- Eero Ilkko
- Department of Diagnostic Radiology, Oulu University Hospital, PL 50, 90029 OYS, Finland.
| | | | | | | |
Collapse
|
246
|
Ratiu P, Talos IF, Haker S, Lieberman D, Everett P. The tale of Phineas Gage, digitally remastered. J Neurotrauma 2004; 21:637-43. [PMID: 15165371 DOI: 10.1089/089771504774129964] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The injury of Phineas Gage has fueled research on and fascination with the localization of cerebral functions in the past century and a half. Most physicians and anatomists believed that Gage sustained a largely bilateral injury to the frontal lobes. However, previous studies seem to have overlooked a few less obvious, but essential details. This has led us to reanalyze the injury using three-dimensional reconstruction and quantitative computer-aided techniques and to propose a new biomechanical model, in order to determine the location and extent of the injury and explain Gage's improbable survival. Unlike previous studies on this subject, our findings are based on computer-generated three-dimensional reconstructions of a thin-slice computed tomography scan (CAT) of Phineas Gage's skull. The results of our image analysis were corroborated with the clinical findings, thoroughly recorded by Dr. Harlow in 1848, as well as with a systematic examination of the original skull specimen. Our results show that the cerebral injury was limited to the left frontal lobe, did not extend to the contralateral side, did not affect the ventricular system, and did not involve vital intracranial vascular structures. Although modern neuroscience has perhaps outgrown the speculations prompted by this famous case, it is still a living part of the medical folklore and education. Setting the record straight based on clinical reasoning, observation of the physical evidence, and sound quantitative computational methods is more than mere minutia and of interest for the broad medical community.
Collapse
Affiliation(s)
- Peter Ratiu
- Department of Radiology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA.
| | | | | | | | | |
Collapse
|
247
|
Kuga M, Yasuda K, Hata N, Dohi T. Navigation system for ACL reconstruction using registration between multi-viewpoint X-ray images and CT images. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.ics.2004.03.137] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
248
|
Yoo S, Talos I, Golby AJ, Black PM, Panych LP. Evaluating requirements for spatial resolution of fMRI for neurosurgical planning. Hum Brain Mapp 2004; 21:34-43. [PMID: 14689508 PMCID: PMC6872071 DOI: 10.1002/hbm.10148] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The unambiguous localization of eloquent functional areas is necessary to decrease the neurological morbidity of neurosurgical procedures. We explored the minimum spatial resolution requirements for functional magnetic resonance imaging (fMRI) data acquisition when brain mapping is used in neurosurgical planning and navigation. Using a 1.5 Tesla clinical MRI scanner, eight patients with brain tumors underwent fMRI scans using spatial resolution of approximately 4 x 4 x 4 mm(3) to map the eloquent motor and language areas during the performance of cognitive/sensorimotor tasks. The fMRI results were then used intra-operatively in an open MRI system to delineate eloquent areas. Retrospectively, activation patterns were visually inspected by a neurosurgeon to determine qualitatively whether ambiguity with respect to the activation boundaries, due to low spatial resolution, could be of potential significance for surgical guidance. A significant degree of ambiguity in both the extent and shape of activation was judged to be present in data from six of the eight patients. Analysis of fMRI data at multiple resolutions from a normal volunteer showed that at 3 mm isotropic resolution, eloquent areas were better localized within the gray matter although there was still some potential for ambiguity caused by activations appearing to cross a sulcus. The data acquired with 2-mm isotropic voxels significantly enhanced the spatial localization of activation to within the gray matter. Thus, isotropic spatial resolution on the order of 2 x 2 x 2 mm(3), which is much higher than the resolutions used in typical fMRI examinations, may be needed for the unambiguous identification of cortical activation with respect to tumors and important anatomical landmarks.
Collapse
Affiliation(s)
- Seung‐Schik Yoo
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Ion‐Florin Talos
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Alexandra J. Golby
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Peter McL. Black
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Lawrence P. Panych
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| |
Collapse
|
249
|
Levitt JJ, Westin CF, Nestor PG, Estepar RSJ, Dickey CC, Voglmaier MM, Seidman LJ, Kikinis R, Jolesz FA, McCarley RW, Shenton ME. Shape of caudate nucleus and its cognitive correlates in neuroleptic-naive schizotypal personality disorder. Biol Psychiatry 2004; 55:177-84. [PMID: 14732598 PMCID: PMC2793335 DOI: 10.1016/j.biopsych.2003.08.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND We measured the shape of the head of the caudate nucleus with a new approach based on magnetic resonance imaging (MRI) in schizotypal personality disorder (SPD) subjects in whom we previously reported decreased caudate nucleus volume. We believe MRI shape analysis complements traditional MRI volume measurements. METHODS Magnetic resonance imaging scans were used to measure the shape of the caudate nucleus in 15 right-handed male subjects with SPD, who had no prior neuroleptic exposure, and in 14 matched normal comparison subjects. With MRI processing tools, we measured the head of the caudate nucleus using a shape index, which measured how much a given shape deviates from a sphere. RESULTS In relation to comparison subjects, neuroleptic never-medicated SPD subjects had significantly higher (more "edgy") head of the caudate shape index scores, lateralized to the right side. Additionally, for SPD subjects, higher right and left head of the caudate SI scores correlated significantly with poorer neuropsychological performance on tasks of visuospatial memory and auditory/verbal working memory, respectively. CONCLUSIONS These data confirm the value of measuring shape, as well as volume, of brain regions of interest and support the association of intrinsic pathology in the caudate nucleus, unrelated to neuroleptic medication, with cognitive abnormalities in the schizophrenia spectrum.
Collapse
Affiliation(s)
- James J Levitt
- Department of Psychiatry, Veterans Affairs Boston Healthcare System, Brockton, Massachusetts 02301, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
250
|
|