| 1. |
- Gorniak, R. J. T., et al.
(författare)
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Evaluation of a semiautomatic 3D fusion technique applied to molecular imaging and MRI brain/frame volume data sets
- 2003
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Ingår i: Journal of medical systems. - 0148-5598 .- 1573-689X. ; 27:2, s. 141-156
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Tidskriftsartikel (refereegranskat)abstract
- A generally applicable {3D} fusion method was evaluated using molecular imaging and {MRI} volumetric data sets from 15 brain tumor patients with stereotactic frames attached to their skull. Point pairs, placed on the frame only, were chosen, polynomial warping coefficients were generated to map voxels from one coordinate space to the other. The {MRI} frame was considered the reference structure and the standard for "correct" registration. An {ANOVA} test (p {\textgreater} 0.05) confirmed the point pair choice to be consistent. The 95\% confidence interval for the t-test showed the measured distance difference between the registered volumes was within one {MRI} voxel. A further experiment was conducted to independently evaluate the brain registration based on testing for consistency of randomly selected interior/exterior points. A t-test result (p {\textless} 0.05) showed that the consistency (i.e., both interior or both exterior) before and after volume registration were significantly different. This fusion method may be a viable alternative when other methods fail.
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| 2. |
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| 3. |
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| 4. |
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| 5. |
- Kimiaei, S., et al.
(författare)
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Evaluation of polynomial image deformation for matching of 3D-abdominal MR-images using anatomical landmarks and for atlas construction
- 1998
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Ingår i: 1998 IEEE Nuclear Science Symposium Conference Record. 1998. - Toronto, Ont., Canada : IEEE. ; , s. 2050-2052
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Konferensbidrag (refereegranskat)abstract
- The aim of this study is to compare and evaluate the potential usability of linear and non-linear (polynomial) 3D-warping for constructing an atlas by matching abdominal MR-images from a number of different individuals using manually picked anatomical landmarks. The significance of this study lies in the fact that it illustrates the potential to use polynomial matching at a local or organ level. This is a necessary requirement for constructing an atlas and for fine intra-patient image matching and fusion. Finally 3D-image warping using anatomical landmark for inter-patient intra-modality image co-registration and fusion was found to be a very powerful and robust method. Additionally it can be used for intra-patient inter-modality image matching.
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| 6. |
- Kimiaei, Sharok, et al.
(författare)
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Evaluation of polynomial image deformation using anatomical landmarks for matching of 3D-abdominal MR-images and for atlas construction
- 1999
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Ingår i: IEEE TRANSACTIONS ON NUCLEAR SCIENCE. - : IEEE. - 0018-9499. ; 46:4, s. 1110-1113
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Tidskriftsartikel (refereegranskat)abstract
- While a variety of different deformation algorithms have been implemented for matching of skull, few attempts in matching areas in abdomen have been reported. In this study the authors evaluate the usability of first and second order polynomial 3D-warping for this purpose. They match abdominal MR-images from different individuals using manually picked anatomical landmarks. Generation of transformation coefficients was done through a linear regression technique that employs a least square fit using the reference landmarks. The landmarks were picked in a predefined order, well spread over the entire data set, by a radiologist. The image resampling was done using linear interpolation and the evaluation was performed visually as well as by calculating the cross correlation and the normalized least squared error between the original image and the transformed image. The authors' preliminary results reveal that the second order polynomial transformation using landmarks is a robust and efficient method. It is also superior to the second order one, for image deformation in the abdominal region and it may be used in atlas generation as well as in multimodality image co-registration and fusion.
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| 7. |
- Maguire Jr., Gerald Q., et al.
(författare)
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A Digital Radiology Department
- 1982
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Ingår i: Medical physics (Lancaster). - 0094-2405. ; 9:4, s. 636-
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Tidskriftsartikel (refereegranskat)
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| 8. |
- Maguire Jr., Gerald Q., et al.
(författare)
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Image Processing Requirements and Distributed Networks in a Digital Imaging Environment
- 1982
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Ingår i: Proceedings of Annual Symposium on Computer Application in Medical Care (SCAMC ’82). - : IEEE. ; , s. 923-
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Konferensbidrag (refereegranskat)abstract
- This paper will discuss a unified digital image distribution and processing system linking various digital image sources through a broadband local area network and a comnon image format. Ultimately, the system allows for viewing and processing of all images produced within the complex, and for viewing stations at any number of convenient locations. The physical handling of storage media at image sources, can be totally eliminated. Complete archiving, file maintenance and large scale processing capabilities are provided by a central file server. This paper presents a concrete proposal for an initial system which has a central archiving facility for permanently storing and selectively viewing computed tomography (CT), nuclear medicine (NM) and ultrasound (US) images. The system proposed can then be slowly expanded to include all the digital images produced by the radiology the department, and ultimately to include all the images by digitizing those produced in an analog fashion.
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| 9. |
- Maguire Jr., Gerald Q., et al.
(författare)
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Interface Requirements in Nuclear Medicine-Devices and Systems
- 1982
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Ingår i: IEEE Transactions on Nuclear Science. - : IEEE. - 0018-9499 .- 1558-1578. ; 29:4, s. 1280-1290
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Tidskriftsartikel (refereegranskat)abstract
- Interface designs for three nuclear medicine imaging systems, and computer networking strategies proposed for medical imaging departments are presented. Configurations for two positron emission tomography devices (PET III and ECAT) and a general purpose tomography instrument (the UNICON) are analyzed in terms of specific performance parameters. Interface designs for these machines are contrasted in terms of utilization of standard versus custom modules, cost, and ease of modification, upgrade, and support. The requirements of general purpose systems for medical image analysis, display, and archiving, are considered, and a realizable state of the art system is specified, including a suggested timetable.
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| 10. |
- Moy, Linda, et al.
(författare)
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Improving specificity of breast MRI using prone PET and fused MRI and PET 3D volume datasets
- 2007
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Ingår i: Journal of Nuclear Medicine. - Reston, Virginia, USA : Society of Nuclear Medicine. - 0161-5505 .- 1535-5667. ; 48:4, s. 528-537
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Tidskriftsartikel (refereegranskat)abstract
- MRI is a sensitive method for detecting invasive breast cancer, but it lacks specificity. To examine the effect of combining PET with MRI on breast lesion characterization, a prototype positioning device was fabricated to allow PET scans to be acquired in the same position as MRI scans-that is, prone. Methods: To test the hypothesis that fusion of 18F-FDG PET and MRI scans improves detection of breast cancer, 23 patients with suspected recurrent or new breast cancer underwent a routine whole-body PET scan, a prone PET scan of the chest, and a routine breast MRJ scan. The attenuation-corrected prone PET and MRI clatasets were registered twice by different operators. The fusion results were judged for quality by visual inspection and statistical analysis. A joint reading of the MRI and PET scans side by side and integrated images was performed by a nuclear medicine physician and a radiologist. Sensitivity and specificity of MRI and combined MRI and PET scans were calculated on the basis of pathology reports or at least 1 y of clinical and radiologic follow-up. Results: All fusions were verified to be well matched using specific anatomic criteria. A total of 45 lesions was assessed. Lesion size range was 0.6 to 10.0 cm. Of the 44 breasts examined, 29 were suspicious for cancer, of which 15 were found to be positive on surgical excision. In lesion-by-lesion analysis, sensitivity and specificity of MRI alone were 92% and 52%, respectively; after MRI and PETfusion, they were 63% and 95%, respectively. The positive predictive value and the negative predictive value for MRI alone were 69% and 85%, respectively; after MRI and PET fusion, they were 94% and 69%, respectively. Conclusion: Acquisition of prone PET scans using the new positioning device permitted acquisition of prone scans suitable for fusion with breast MRI scans. Fused PET and MRI scans increased the specificity of MRI but decreased the sensitivity in this small group of patients. Additional data are needed to confirm the statistical significance of these preliminary findings.
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| 11. |
- Moy, Linda, et al.
(författare)
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Prone mammoPET acquisition improves the ability to fuse MRI and PET breast scans
- 2007
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Ingår i: Clinical Nuclear Medicine. - Philadephia, Pennsylvania, USA : Lippincott Williams & Wilkins. - 0363-9762 .- 1536-0229. ; 32:3, s. 194-198
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: This study compared prone acquisition of PET scans with traditional supine acquisition to improve fusion of PET scans with MRI scans and improve evaluation of enhancing breast lesions detected on MRI. Materials and Methods: MRI breast scans are acquired in the prone position using a breast coil to allow the breasts to hang pendant. An apparatus was fabricated to allow prone acquisition of PET scans. Fused scans from 2 patients acquired both prone and supine were contrasted with those from 3 patients acquired supine only. All 5 MRI scans were acquired on standard scanners. The PET scans were acquired with a PET/CT unit using a low-dose CT scan for attenuation correction. The PET and MRI volumes were matched twice (using a semiautomated registration method) by different operators. The additional value of fusion was judged using reports from the original (nonfused) MRI and PET, joint rereading of the volumes side by side, and examination of fused images. Results: Of 12 enhancing lesions on breast MRI, 7 demonstrated uptake on PET/CT. In the 3 supine-only cases, the fused images were not interpretable because of the marked distortion of the breasts. In the 2 prone cases, the fused images increased our confidence in characterizing a lesion as benign or malignant. Interpretations were confirmed by clinical follow up in 2 or histologic results in 3 patients. Conclusions: PET MRI fusion is feasible and may assist in localizing lesions detected on either study. A more extensive study is under-way to confirm the value of this fusion technique.
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| 12. |
- Moy, Linda, et al.
(författare)
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Role of Fusion of Prone FDG-PET and Magnetic Resonance Imaging of the Breasts in the Evaluation of Breast Cancer
- 2010
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Ingår i: The Breast Journal. - : Hindawi Limited. - 1075-122X .- 1524-4741. ; 16:4, s. 369-376
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study is to report further about the statistically significant results from a prospective study, which suggests that fusion of prone F-18 Fluoro-deoxy-glucose (FDG) positron emission tomography (PET) and magnetic resonance (MR) breast scans increases the positive predictive value (PPV) and specificity for patients in whom the MR outcome alone would be nonspecific. Thirty-six women (mean age, 43 years; range, 24-65 years) with 90 lesions detected on MR consented to undergo a FDG-PET scan. Two blinded readers evaluated the MR and the computer tomography (CT) attenuation-corrected prone FDG-PET scans side-by-side, then after the volumes were superimposed (fused). A semiautomatic, landmark-based program was used to perform nonrigid fusion. Pathology and radiologic follow-up were used as the reference standard. The sensitivity, specificity, PPV, negative predictive value (NPV), and accuracy (with 95% confidence intervals) for MR alone, FDG-PET alone, and fused MR and FDG-PET were calculated. The median lesion size measured from the MR was 2.5 cm (range, 0.5-10 cm). Histologically, 56 lesions were malignant, and 15 were benign. Nineteen lesions were benign after 20-47 months of clinical and radiologic surveillance. The sensitivity of MR alone was 95%, FDG-PET alone was 57%, and fusion was 83%. The increase in PPV from 77% in MR alone to 98% when fused and the increase in specificity from 53% to 97% were statistically significant (p < 0.05). The false-negative rate on FDG-PET alone was 26.7%, and after fusion this number was reduced to 9%. FDG-PET and MR fusions were helpful in selecting which lesion to biopsy, especially in women with multiple suspicious MR breast lesions.
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| 13. |
- Noz, Marilyn E., et al.
(författare)
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Graphical interface for medical image processing
- 1993
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Ingår i: Journal of medical systems. - 0148-5598 .- 1573-689X. ; 17:1, s. 1-16
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Tidskriftsartikel (refereegranskat)abstract
- We have developed a graphical interface which allows users of varying levels of computer experience and proficiency to manipulate medical image-processing data with "point-and-click" ease. The power which had formerly been associated with protocols and shell scripts has been combined with the flexibility and "user-friendliness" of buttons and dialog boxes.
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| 14. |
- Olivecrona, Henrik, et al.
(författare)
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A new CT method for measuring cup orientation after total hip arthroplasty : A study of 10 patients
- 2004
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Ingår i: Acta Orthopaedica Scandinavica. - : Medical Journals Sweden AB. - 0001-6470. ; 75:3, s. 252-260
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Tidskriftsartikel (refereegranskat)abstract
- Background It is difficult to assess the orientation of the acetabular component on routine radiographs. We present a method for determining the spatial orientation of the acetabular component after total hip arthroplasty (THA) using computed tomography. Patients and methods Two CT-scans, 10 min apart, were obtained from each of 10 patients after THA. Using locally developed software, two independent examiners measured the orientation of the acetabular component in relation to the pelvis. The measurements were repeated after one week. To be independent of the patient position during scanning, the method involved two steps. Firstly, a 3D volumetric image of the pelvis was brought into a standard pelvic orientation, then the orientation of the acetabular component was measured. The orientation of the acetabular component was expressed as operative anteversion and inclination relative to an internal pelvic reference coordinate system. To evaluate precision, we compared measurements across pairs of CT volumes between observers and trials. Results Mean absolute interobserver angle error was 2.3degrees for anteversion (range 0-6.6degrees), and 1.1degrees for inclination (range 0-4.6degrees). For interobserver measurements, the precision, defined as one standard deviation, was 2.9degrees for anteversion, and 1.5degrees for inclination. A Student's West showed that the overall differences between the examiners, trials, and cases were not significant. Data were normally distributed and were not dependent on examiner or trial. Interpretation We conclude that the implant angles of the acetabular component in relation to the pelvis could be detected repeatedly using CT, independently of patient positioning.
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| 15. |
- Olivecrona, Henrik, et al.
(författare)
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Spatial component position in total hip arthroplasty - Accuracy and repeatability with a new CT method
- 2003
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Ingår i: Acta Radiologica. - : SAGE Publications. - 0284-1851 .- 1600-0455. ; 44:1, s. 84-91
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: 3D detection of centerpoints of prosthetic cup and head after total hip arthroplasty (THA) using CT. Material and Methods: Two CT examinations, 10 min apart, were obtained from each of 10 patients after THA. Two independent examiners placed landmarks in images of the prosthetic cup and head. All landmarking was repeated after 1 week. Centerpoints were calculated and compared. Results: Within volumes, all measurements of centerpoints of cup and head fell, with a 95% confidence, within one CT-voxel of any other measurement of the same object. Across two volumes, the mean error of distance between center of cup and prosthetic head was 1.4 mm (SD 0.73). Intra- and interobserver 95% accuracy limit was below 2 mm within and below 3 mm across volumes. No difference between intra- and interobserver measurements occurred. A formula for converting finite sets of point landmarks in the radiolucent tread of the cup to a centerpoint was stable. The percent difference of the landmark distances from a calculated spherical surface was within one CT-voxel. This data was normally distributed and not dependent on observer or trial. Conclusion: The true 3D position of the centers of cup and prosthetic head can be detected using CT. Spatial relationship between the components can be analyzed visually and numerically.
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| 16. |
- Olivecrona, Henrik, et al.
(författare)
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Stability of acetabular axis after total hip arthroplasty, repeatability using CT and a semiautomated program for volume fusion
- 2003
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Ingår i: Acta Radiologica. - : SAGE Publications. - 0284-1851 .- 1600-0455. ; 44:6, s. 653-661
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To validate a CT method for detecting changes in acetabular cup orientation after THA. Material and Methods: 26 CT examinations were obtained from a pelvic model with an uncemented acetabular cup. The model position was altered between acquisitions, but the cup axis angle vis-a-vis the pelvis was maintained. Data sets were combined into 37 pairs, each containing a unique positioning error. The pelvi in different examinations were fused, creating transformed volumes. Landmarks corresponding to the cup before and after fusion were placed interactively by two independent examiners. The orientation of the acetabular axis was calculated for each volume and compared across volumes. Results: Before fusion the mean angle error between the acetabular axes was 4.17degrees (SD +/- 1.95degrees). After fusion the mean angle error was 0.36degrees (SD +/- 0.17). The 95% repeatability limits were below 0.7degrees. There was no significant interobserver difference. Analysis of the cup landmarking pattern by condition numbers and individual landmark errors showed stability. Conclusion: Non-invasive fusion of CT volumes and a stable landmarking pattern for the acetabular cup outperforms routine plain radiography in detecting changes in the orientation of the acetabular axis over time. The method delivers both visual and numerical output and could be used in clinical practice.
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| 17. |
- Olivecrona, Lotta, et al.
(författare)
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Acetabular component migration in total hip arthroplasty using CT and a semiautomated program for volume merging
- 2002
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Ingår i: Acta Radiologica. - : SAGE Publications. - 0284-1851 .- 1600-0455. ; 43:5, s. 517-527
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To develop a non-invasive method for detection of acetabular cup migration after total hip arthroplasty (THA) with a higher degree of accuracy than routine plain radiography. Material and Methods: Two CT examinations, 10 min apart, were obtained from each of 10 patients that had undergone THA. Using an in-house developed semiautomated program for volume merging, the pelves in the two examinations were fused and the acetabular cup was visually and numerically evaluated to test the method's accuracy in detecting migration. Results: In the visual evaluation of the best match a 1-mm translation of the cup was detectable. The numerical evaluation, comparing landmarks placed in the images of the acetabular cup and the head of the femur component in the two examinations, showed the mean difference in orientation of acetabular axes to be 2.5degrees, the mean distance between centre of cup face to be 2.5 mm and the mean distance between centre of the head of the prosthetic femoral component to be 1 mm. Conclusion: This method has a significantly higher accuracy than routine plain radiography in detecting acetabular cup migration and could be used in clinical practice. It gives both a visual and a numerical correlate to migration.
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| 18. |
- Olivecrona, Lotta, et al.
(författare)
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Standard orientation of the pelvis : Validation on a model and ten patients
- 2005
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Ingår i: Acta Radiologica. - London, UK : Informa Healthcare. - 0284-1851 .- 1600-0455. ; 46:1, s. 74-82
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To validate an image post-processing method for re-orienting the pelvis in CT volumes to a standardized orientation in a model and in 10 patients. Material and Methods: Twenty-four CT volumes of a pelvic model and 10 pairs of postoperative total hip arthroplasty (THA) patient CT scans were rotated to a defined pelvic standard orientation and the rotation was recorded. For precision, a test-retest procedure was used. For accuracy, three exactly represented coordinate points were used. For clinical application, the standard orientation was used for calculating the direction of acetabular cup migration from a previous model study. Results: Precision of pelvic standard orientation, calculated as maximal directional error, was better than 1degrees in the model study and better than 1.5degrees in the patient study. Accuracy, expressed as angle between ideal and measured coordinate axes, was 0.1degrees for x, y, z axes. No measurable systematic errors were found. When applied to acetabular cup migration in the model, standardization of pelvic orientation had no significant effect on the measurements. Conclusion: Reorienting the pelvis during image post-processing was shown to be accurate. It enables measurements relative to the pelvis and minimizes the dependency of patient positioning.
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| 19. |
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| 20. |
- Aitken, Candice L., et al.
(författare)
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Comparison of three methods used for fusion of SPECT-CT images of liver matastases
- 1998
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Ingår i: Fusion98, International Conference on Multisource-Mulltisensor Information Fusion. - : CSREA Press. - 1892512009 ; , s. 435-442
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Konferensbidrag (refereegranskat)abstract
- We compare three methods for fusing SPECT-CT images: ImageMatch - an automatic three-dimensional/two-dimensional method developed by Focus Imaging; IBM Visualization Data Explorer - a three-diemensional interactive method developed by Internation Business Machines, Inc.; and qsh - an interactive three-dimensional/two-dimensional method developed at New York University. While many fusion methods have proved successful for registering brain images, most methods have been less successful for thoracic and abdominal images. We use images of liver metastases obtained with a radiolabeled breast tumor-directed antibody to illustrate the strengths and weakness of the methods reviewed. The images used are typical clinical images from eigth patients. We conclude that an optimal image fusion program should combine the strengths of each of the methods reviewed.
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| 21. |
- Aitken, Candice L., et al.
(författare)
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Tumor localization and image registration of 18-FDG SPECT scans with CT scans
- 1999
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Ingår i: Journal of Nuclear Medicine. - : Society of Nuclear Medicine. - 0161-5505 .- 1535-5667. ; 40:5, s. 290P-291P
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The aim of this study was to determine the feasibility of registering routine clinical F-18 fluorodeoxyglucose (FDG) coincidence detection (CD) scans with computed tomographic (CT) scans for radiation treatment planning and case management. METHODS: F-18 FDG CD and chest CT scans, performed in 10 randomly selected patients with confirmed or possible adenocarcinoma of the lung, were evaluated. The quality of the matches was verified by comparisons of the center-to-center distance between a region of interest (ROI) manually drawn on the CT slice and warped onto the CD slice with an ROI drawn manually directly on the CD slice. In addition, the overlap between the two ROIs was calculated. RESULTS: All 10 F-18 FDG CD and CT scans were registered with good superimposition of soft tissue density on increased radionuclide activity. The center-to-center distance between the ROIs ranged from 0.29 mm to 8.08 mm, with an average center-to-center distance of 3.89 mm +/- 2.42 mm (0.69 pixels +/- 0.34 pixels). The ROI overlap ranged from 77% to 99%, with an average of 90% +/- 5.6%. CONCLUSIONS: Although the use of F-18 FDG CD shows great promise for the identification of tumors, it shares the same drawbacks as those associated with radiolabeled monoclonal antibody SPECT and ligand-based positron emission tomographic scans in that anatomic markers are limited. This study shows that image registration is feasible and may improve the clinical relevance of CD images.
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| 22. |
- Aitken, Candice L., et al.
(författare)
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Tumor localization and image registration of F-18FDG coincidence detection scans with computed tomographic scans
- 2002
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Ingår i: Clinical Nuclear Medicine. - : Ovid Technologies (Wolters Kluwer Health). - 0363-9762 .- 1536-0229. ; 27:4, s. 275-282
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: The aim of this study was to determine the feasibility of registering routine clinical F-18 fluorodeoxyglucose (FDG) coincidence detection (CD) scans with computed tomographic (CT) scans for radiation treatment planning and case management. Methods: F-18 FDG CD and chest CT scans, performed in 10 randomly selected patients with confirmed or possible adenocarcinoma of the lung, were evaluated. The quality of the matches was verified by comparisons of the center-to-center distance between a region of interest (ROI) manually drawn on the CT slice and warped onto the CD slice with an ROI drawn manually directly on the CD slice. In addition, the overlap between the two ROIs was calculated. Results: All 10 F-18 FDG CD and CT scans were registered with good superimposition of soft tissue density on increased radionuclide activity. The center-to-center distance between the ROIs ranged from 0.29 mm to 8.08 mm, with an average center-to-center distance of 3.89 mm 2.42 mm (0.69 pixels +/- 0.34 pixels). The ROI overlap ranged from 77% to 99%, with an average of 90% +/- 5.6%. Conclusions: Although the use of F-18 FDG CD shows great promise for the identification of tumors, it shares the same drawbacks as those associated with radiolabeled monoclonal antibody SPECT and ligand-based positron emission tomographic scans in that anatomic markers are limited. This study shows that image registration is feasible and may improve the clinical relevance of CD images.
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| 23. |
- Alcala, Yvonne, et al.
(författare)
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Qualifying CT for wrist arthroplasty : Extending techniques for total hip arthroplasty to total wrist arthroplasty
- 2005
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Ingår i: Medical Imaging 2005. - : SPIE - The International Sooceity for Optical Engineeering. - 0819457213 ; , s. 1155-1164
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Konferensbidrag (refereegranskat)abstract
- The purpose of this study was to extend previous work to detect migration of total wrist arthroplasty non-invasively, and with greater accuracy. Two human cadaverous arms, each with a cemented total wrist implant, were used in this study. In one of the arms, I mm tantalum balls were implanted, six in the carpal bones and five in the radius. Five CT scans of each arm were acquired, changing the position of the arm each time to mimic different positions patients might take on repeated examinations. Registration of CT volume data sets was performed using an extensively validated, 3D semi-automatic volume fusion tool in which co-homologous point pairs (landmarks) are chosen on each volume to be registered. Three sets of ten cases each were obtained by placing landmarks on 1) bone only (using only arm one), 2) tantalum implants only, and 3) bone and tantalum implants (both using only arm two). The accuracy of the match was assessed visually in 2D and 3D, and numerically by calculating the distance difference between the actual position of the transformed landmarks and their ideal position (i.e., the reference landmark positions). All cases were matched visually within one width of cortical bone and numerically within one half CT voxel (0.32 mm, p = 0.05). This method matched only the bone/arm and not the prosthetic component per se, thus making it possible to detect prosthetic movement and wear. This method was clinically used for one patient with pain. Loosening of the carpal prosthetic component was accurately detected and this was confirmed at surgery.
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| 24. |
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| 25. |
- Anderlind, Eva, et al.
(författare)
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Will haptic feedback speed up medical imaging? An application to radiation treatment planning
- 2008
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Ingår i: Acta Oncologica. - OSLO, Norge : Taylor & Francis. - 0284-186X .- 1651-226X. ; 47:1, s. 32-37
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Tidskriftsartikel (refereegranskat)abstract
- Haptic technology enables us to incorporate the sense of touch into computer applications, providing an additional input/output channel. The purpose of this study was to examine if haptic feedback can help physicians and other practitioners to interact with medical imaging and treatment planning systems. A haptic application for outlining target areas (a key task in radiation therapy treatment planning) was implemented and then evaluated via a controlled experiment with ten subjects. Even though the sample size was small, and the application only a prototype, results showed that haptic feedback can significantly increase (p0.05) the speed of outlining target volumes and organs at risk. No significant differences were found regarding precision or perceived usability. This promising result warrants further development of a full haptic application for this task. Improvements to the usability of the application as well as to the forces generated have been implemented and an experiment with more subjects is planned.
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