Poster No.: C-1848 Congress: ECR Educational Exhibit. Authors:

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1 Understanding " the fusion imaging " - Methods of fusion with their advantages and disadvantages and study various fusion combination with their applications. Poster No.: C-1848 Congress: ECR 2017 Type: Authors: Educational Exhibit P. P. singh 1, K. Gahlot 2, R. Mourya 2, V. Gahlot 2 ; 1 sagar, m.p./in, 2 Sagar/IN Keywords: DOI: Hybrid Imaging, Molecular imaging, Nuclear medicine, PET-CT, SPECT-CT, PET-MR, Technical aspects, Comparative studies, Computer Applications-Detection, diagnosis, Hemodynamics / Flow dynamics, Education and training, Multidisciplinary cancer care /ecr2017/C-1848 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 11

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3 Learning objectives Learning objectives: 1. To understand "the fusion imaging." Methods 2. Methods of fusion with their advantages and disadvantages. 3. To study various fusion combination with their applications. Background Fusion imaging is the process of merging and visualization of anatomical, functional and chemical information from two or more images in to single image in a more meaningful and synergistic manner. 1,2 Within the medical imaging environment, these data sources include modalities such as PET, SPECT, CT, and MR imaging. Image fusion technology fuses may be from different imaging modalities or from the same modality acquired at different times (such as pre- and post - treatment images). 3 Starting from X - ray to other imaging modalities like USG,CT and MRI differentiate disease from normal tissue by revealing structural differences or difference in regional perfusion of the administered contrast media. This can be complicated by prior surgery or radiotherapy where contrast patterns can mimic those associated with neoplasia. This poses difficulty in defining anatomic extend of disease. Comparison to those anatomic imaging techniques, functional imaging methods assess regional alteration and differences in the biochemical status of tissues. Now fusion of functional - anatomic imaging is well established and also its clinical value widely recognized. Findings and procedure details The fusion software typically calls for two sets of data from the same patient selected for fusion. One is selected as the "primary" set to which the other will be registered.it is best to keep the original image resolution of each image set and retain its quantitative information. 1 Page 3 of 11

4 The two blocks of data used do not start as registered images. The patient is scanned at different times, in different machines, and in different positions. The fusion software typically calls for two sets of data from the same patient selected for fusion.one is selected as the "primary" set to which the other will be registered.it is best to keep the original image resolution of each image set and retain its quantitative information.the two blocks of data used do not start as registered images. The patient is scanned at different times, in different machines, and in different positions.different size acquisitions with different slice thickness and pixel sizes with different central points are the norm. Voxel dimensions can be adjusted from measurements provided by calibration and quality control images. Adjustments required for registration take into account the X, Y, and Z coordinate offsets between the data blocks.the real trigonometry delight is correction of angular offsets between the two blocks of data. The alignment steps leading to coregistration can be guided effectively by the trained eye using interactive software.the use of feducial markers detected by both modalities is used.a small point source of radioisotope mixed with Vitamin E works for SPECT/ MR fusion scans.a point source of F-18 fluorodeoxyglucose (FDG) in a radiographically opaque cup works for PET/CT fusion. These feducial points placed on the surface of the patient are steered together with software that superimposes them to achieve accurate coregistration. Theoretically, only three feducials are needed to coregister two volumes of data. Many fusion imagers use a minimum of six. In reality, these surface feducials are a simple case of anatomic structures within the patient that are visible to each separate modality.many scans have plenty of common structures, but there is a question of the operator's subjective interference with the process. He or she may want to "slide" an abnormality from a SPECT or PET scan on top of a particular anatomic finding on a MR or CT scan.automated software programs are in development that use information common to both scans.mutual information algorithms have been developed that seek the minimum differences or maximum similarities between two cubic data sets from different modalities. Through an iterative process, these programs can bring data sets objectively into registration. The development of the transmission scan came from the need to measure attenuation in SPECT and PET scans. The transmission scan is coregistered with the emission scan automatically and is actually a low-resolution version of a CT scan.it has a lot of information in common with a CT scan. If a CT scan and transmission scan are fed to the right algorithm, they can be coregistered precisely without the operator's subjective opinion.the registration parameters derived for the transmission scan are applied to the emission scan to produce a fusion of the images Display of fused images usually requires an overlay of a gray-scale image for the anatomic image (CT or MR) and a color scale for the nuclear medicine image (SPECT or PET). Dithering the two images so that every other pixel is displayed from each coregistered study on a basis is the solution favored by the authors. Side-by-side comparison with interrogation of both coregistered images by regions of interest (ROIs) drawn on one or the other is helpful in some cases. Page 4 of 11

5 ADVANTAGES OF FUSION IMAGING - Fusion Imaging Linking functional and anatomic image data via fusion of PET and CT/MR, or use of combined PET/CT imaging, provides additional clinically relevant information. It may be the modality of choice because it almost completely eliminates the false-positive and false-negative PET findings. 4 Advantages - i. More accurately identifying the margins of a tumor/ metastasis. ii. There is better identifying small recunent tumors obscured by scar tissue at site of incipient radiation or postoperative necrosis. iii. Detecting large tumors that lay in clinically inaccessible areas, such as the hypopharynx or maxilla. iv. Locating the primary lesion in unknown primary tumors. v. Combined imaging is superior in staging of tumors. vi. Guiding of treatment including planning, guidance of biopsy, surgery or radiation therapy. 5 vii. Providing structural and functional information in the same image. viii. Improving reading efficiency. ix. Improving confidence in diagnosis when one modality alone is not definitive. x. Quantification of the difference between scans. xi. Radiation therapy planning. Images for this section: Page 5 of 11

6 Fig. 1: PROCEDURE FLOW CHART PART - 1 DR PUNYA PRATAP SINGH Page 6 of 11

7 Fig. 2: PROCEDURE FLOW CHART PART - 2 DR PUNYA PRATAP SINGH Page 7 of 11

8 Fig. 3: PER MR CONCEPT IMAGE The Clinical Role of Fusion Imaging Using PET, CT, and MR Imaging Habib Zaidi, PhD, PDa,*, Marie-Louise Montandon, PhDa, Abass Alavi, MD, PhD (Hon), DSc (Hon) Page 8 of 11

9 Fig. 4: PET CT CONCEPT IMAGE radiodiagnosis, budelkhand medical collage, bundelkhand medical collage - sagar/in Page 9 of 11

10 Conclusion Interpretation of fused images is better than separate interpretation of either PET or CT/ MRI images standing by themselves. It allows us to help physicians treat tumors earlier by providing la more specific, comprehensive picture of the disease. 6 Fusion imaging blurs the boundaries between the different medical specialties. Nuclear medicine physicians are now able to see their SPECT studies in the context of a CT or MR study with greater anatomical detail. Fusion between 2D and 3D modalities is also possible. Surgeons and physicians can view all of the imaging studies they have ordered in a more holistic manner. Radiologists can extend their practice into functional imaging studies. This is threatening to some, but this improved utilization of patient data will ultimately benefit quality of care. 2 Even before formal studies are available in the literature, the fusion image that combines a nuclear medicine image and an anatomic image, or two nuclear medicine images, or two anatomic images, helps with the three "C's". 1 Findings are made more conspicuous as one study (usually the nuclear medicine image) provides enhancement of the findings on the other. Findings are clarified as one study is used to explain the findings on the other (and this "C" works both ways). Diagnostic certainty improves, as the reading physician becomes more confident as a result of viewing the fusion images. Fusion imaging has arrived. Personal information References 1. Philip W. Wiest and Michael F. Hartshorne. Image Fusion. Applied Radiology. 2001;30(4). Page 10 of 11

11 2. Leong Joel F, Siegel Alan H. Clinical applications of fusion imaging. Applied Radiology Nov 2003;32(11). 3. Hellman Robert S. Fusion imaging, everyday, Sep-Ike Paulino AC, Thorstad WL, Fox T. Role of fusion in radio-theraphy treatment planning. Semin Nucl Med 2003;23(3): Stokking R, Zubal 1G, Viergever MA. Display of fused images: Methods, interpretation, and diagnostic improvements. Semin Nucl Med 2003;23(3): CoreiaiA. Registration of nuclear medicine images. J Nuel Med 1990;31:1227. Page 11 of 11