1
|
Birckhead BJ, Fossum CC, Deufel CL, Furutani KM, Merrell KW, Schueler BA, Mynderse LA, Choo R, Davis BJ. Stranded seed displacement, migration, and loss after permanent prostate brachytherapy as estimated by Day 0 fluoroscopy and 4-month postimplant pelvic x-ray. Brachytherapy 2016; 15:714-721. [PMID: 27542893 DOI: 10.1016/j.brachy.2016.07.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 06/27/2016] [Accepted: 07/15/2016] [Indexed: 10/21/2022]
Abstract
PURPOSE The aim of the study was to determine the incidence of local displacement, distant seed migration to the chest, and seed loss after permanent prostate brachytherapy (PPB) with stranded seeds (SSs) using sequential two-dimensional fluoroscopic pelvic and chest x-rays. METHODS AND MATERIALS Between October 2010 and April 2014, a total of 137 patients underwent PPB and 4-month followup pelvic and chest x-ray imaging. All patients had exclusively SSs placed and an immediate postimplant fluoroscopic image of the seed cluster. Followup x-ray images were evaluated for the number, location, and displacement of seeds in comparison to Day 0 fluoroscopic images. Significant seed displacement was defined as seed displacement >1 cm from the seed cluster. Followup chest x-rays were evaluated for seed migration to the chest. RESULTS Seed migration to the chest occurred in 3 of the 137 patients (2%). Seed loss occurred in 38 of the 137 patients (28%), with median loss of one seed (range, 1-16), and total seeds loss of 104 of 10,088 (1.0%) implanted. Local seed displacement was seen in 12 of the 137 patients (8.8%), and total seeds displaced were 0.15% (15/10,088). CONCLUSIONS SS placement in PPB is associated with low rates of substantial seed loss, local displacement, or migration to the chest. Comparing immediate postimplant fluoroscopic images to followup plain x-ray images is a straightforward method to supplement quality assurance in PPB and was found to be useful in identifying cases where seed loss was potentially of clinical significance.
Collapse
Affiliation(s)
- B J Birckhead
- Mayo Medical School, Mayo Clinic and Foundation, Rochester, MN
| | - C C Fossum
- Mayo Medical School, Mayo Clinic and Foundation, Rochester, MN
| | - C L Deufel
- Department of Radiation Oncology, Mayo Clinic and Foundation, Rochester, MN
| | - K M Furutani
- Department of Radiation Oncology, Mayo Clinic and Foundation, Rochester, MN
| | - K W Merrell
- Department of Radiation Oncology, Mayo Clinic and Foundation, Rochester, MN
| | - B A Schueler
- Department of Radiology, Mayo Clinic and Foundation, Rochester, MN
| | - L A Mynderse
- Department of Urology, Mayo Clinic and Foundation, Rochester, MN
| | - R Choo
- Department of Radiation Oncology, Mayo Clinic and Foundation, Rochester, MN
| | - B J Davis
- Department of Radiation Oncology, Mayo Clinic and Foundation, Rochester, MN.
| |
Collapse
|
2
|
Mehrmohammadi M, Alizad A, Kinnick RR, Davis BJ, Fatemi M. Feasibility of vibro-acoustography with a quasi-2D ultrasound array transducer for detection and localizing of permanent prostate brachytherapy seeds: a pilot ex vivo study. Med Phys 2015; 41:092902. [PMID: 25186418 DOI: 10.1118/1.4893532] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
PURPOSE Effective permanent prostate brachytherapy (PPB) requires precise placement of radioactive seeds in and around the prostate. The impetus for this research is to examine a new ultrasound-based imaging modality, vibro-acoustography (VA), which may serve to provide a high rate of PPB seed detection while also effecting enhanced prostate imaging. The authors investigate the ability of VA, implemented on a clinical ultrasound (US) scanner and equipped with a quasi-2D (Q2D) array US transducer, to detect and localize PPB seeds in excised prostate specimens. METHODS Nonradioactive brachytherapy seeds were implanted into four excised cadaver prostates. A clinical US scanner equipped with a Q2D array US transducer was customized to acquire both US and C-scan VA images at various depths. The VA images were then used to detect and localize the implanted seeds in prostate tissue. To validate the VA results, computed tomography (CT) images of the same tissue samples were obtained to serve as the reference by which to evaluate the performance of VA in PPB seed detection. RESULTS The results indicate that VA is capable of accurately identifying the presence and distribution of PPB seeds with a high imaging contrast. Moreover, a large ratio of the PPB seeds implanted into prostate tissue samples could be detected through acquired VA images. Using CT-based seed identification as the standard, VA was capable of detecting 74%-92% of the implanted seeds. Additionally, the angular independency of VA in detecting PPB seeds was demonstrated through a well-controlled phantom experiment. CONCLUSIONS Q2DVA detected a substantial portion of the seeds by using a 2D array US transducer in excised prostate tissue specimens. While VA has inherent advantages associated with conventional US imaging, it has the additional advantage of permitting detection of PPB seeds independent of their orientation. These results suggest the potential of VA as a method for PPB imaging that ultimately may allow US-based real-time intraoperative dosimetry.
Collapse
Affiliation(s)
- Mohammad Mehrmohammadi
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota 55905
| | - Azra Alizad
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota 55905 and Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota 55905
| | - Randall R Kinnick
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota 55905
| | - Brian J Davis
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota 55905
| | - Mostafa Fatemi
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota 55905
| |
Collapse
|
3
|
Knaup C, Mavroidis P, Esquivel C, Stathakis S, Swanson G, Baltas D, Papanikolaou N. Investigating the dosimetric and tumor control consequences of prostate seed loss and migration. Med Phys 2012; 39:3291-8. [PMID: 22755712 DOI: 10.1118/1.4712227] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Low dose-rate brachytherapy is commonly used to treat prostate cancer. However, once implanted, the seeds are vulnerable to loss and movement. The goal of this work is to investigate the dosimetric and radiobiological effects of the types of seed loss and migration commonly seen in prostate brachytherapy. METHODS Five patients were used in this study. For each patient three treatment plans were created using Iodine-125, Palladium-103, and Cesium-131 seeds. The three seeds that were closest to the urethra were identified and modeled as the seeds lost through the urethra. The three seeds closest to the exterior of prostatic capsule were identified and modeled as those lost from the prostate periphery. The seed locations and organ contours were exported from Prowess and used by in-house software to perform the dosimetric and radiobiological evaluation. Seed loss was simulated by simultaneously removing 1, 2, or 3 seeds near the urethra 0, 2, or 4 days after the implant or removing seeds near the exterior of the prostate 14, 21, or 28 days after the implant. RESULTS Loss of one, two or three seeds through the urethra results in a D(90) reduction of 2%, 5%, and 7% loss, respectively. Due to delayed loss of peripheral seeds, the dosimetric effects are less severe than for loss through the urethra. However, while the dose reduction is modest for multiple lost seeds, the reduction in tumor control probability was minimal. CONCLUSIONS The goal of this work was to investigate the dosimetric and radiobiological effects of the types of seed loss and migration commonly seen in prostate brachytherapy. The results presented show that loss of multiple seeds can cause a substantial reduction of D(90) coverage. However, for the patients in this study the dose reduction was not seen to reduce tumor control probability.
Collapse
Affiliation(s)
- Courtney Knaup
- Department of Radiation Oncology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA.
| | | | | | | | | | | | | |
Collapse
|
4
|
Jain A, Deguet A, Iordachita I, Chintalapani G, Vikal S, Blevins J, Le Y, Armour E, Burdette C, Song D, Fichtinger G. Intra-operative 3D guidance and edema detection in prostate brachytherapy using a non-isocentric C-arm. Med Image Anal 2012; 16:731-43. [PMID: 21168357 PMCID: PMC4695983 DOI: 10.1016/j.media.2010.07.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Revised: 03/01/2010] [Accepted: 07/22/2010] [Indexed: 11/23/2022]
Abstract
PURPOSE Brachytherapy (radioactive seed insertion) has emerged as one of the most effective treatment options for patients with prostate cancer, with the added benefit of a convenient outpatient procedure. The main limitation in contemporary brachytherapy is faulty seed placement, predominantly due to the presence of intra-operative edema (tissue expansion). Though currently not available, the capability to intra-operatively monitor the seed distribution, can make a significant improvement in cancer control. We present such a system here. METHODS Intra-operative measurement of edema in prostate brachytherapy requires localization of inserted radioactive seeds relative to the prostate. Seeds were reconstructed using a typical non-isocentric C-arm, and exported to a commercial brachytherapy treatment planning system. Technical obstacles for 3D reconstruction on a non-isocentric C-arm include pose-dependent C-arm calibration; distortion correction; pose estimation of C-arm images; seed reconstruction; and C-arm to TRUS registration. RESULTS In precision-machined hard phantoms with 40-100 seeds and soft tissue phantoms with 45-87 seeds, we correctly reconstructed the seed implant shape with an average 3D precision of 0.35 mm and 0.24 mm, respectively. In a DoD Phase-1 clinical trial on six patients with 48-82 planned seeds, we achieved intra-operative monitoring of seed distribution and dosimetry, correcting for dose inhomogeneities by inserting an average of over four additional seeds in the six enrolled patients (minimum 1; maximum 9). Additionally, in each patient, the system automatically detected intra-operative seed migration induced due to edema (mean 3.84 mm, STD 2.13 mm, Max 16.19 mm). CONCLUSIONS The proposed system is the first of a kind that makes intra-operative detection of edema (and subsequent re-optimization) possible on any typical non-isocentric C-arm, at negligible additional cost to the existing clinical installation. It achieves a significantly more homogeneous seed distribution, and has the potential to affect a paradigm shift in clinical practice. Large scale studies and commercialization are currently underway.
Collapse
Affiliation(s)
- A Jain
- Johns Hopkins University, Baltimore, MD 21210, United States.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Moult E, Fichtinger G, Morris WJ, Salcudean SE, Dehghan E, Fallavollita P. Segmentation of iodine brachytherapy implants in fluoroscopy. Int J Comput Assist Radiol Surg 2012; 7:871-9. [PMID: 22447486 DOI: 10.1007/s11548-012-0679-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 02/29/2012] [Indexed: 10/28/2022]
Abstract
PURPOSE In prostate brachytherapy, intraoperative dosimetry would allow for evaluation of the implant quality while the patient is still in treatment position. Such a mechanism, however, requires 3-D visualization of the deposited seeds relative to the prostate. It follows that accurate and robust seed segmentation is of critical importance in achieving intraoperative dosimetry. METHODS Implanted iodine brachytherapy seeds are segmented via a region-based implicit active contour model. Overlapping seed groups are then resolved using a template-based declustering technique. RESULTS Ground truth seed coordinates were obtained through manual segmentation. A total of 57 clinical C-arm images from 10 patients were used to validate the proposed algorithm. This resulted in two failed images and a 96.0% automatic detection rate with a corresponding 2.2% false-positive rate in the remaining 55 images. The mean centroid error between the manual and automatic segmentations was 1.2 pixels. CONCLUSIONS Robust and accurate iodine seed segmentation can be achieved through the proposed segmentation workflow.
Collapse
|
6
|
Dehghan E, Moradi M, Wen X, French D, Lobo J, Morris WJ, Salcudean SE, Fichtinger G. Prostate implant reconstruction from C-arm images with motion-compensated tomosynthesis. Med Phys 2011; 38:5290-302. [PMID: 21992346 DOI: 10.1118/1.3633897] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Accurate localization of prostate implants from several C-arm images is necessary for ultrasound-fluoroscopy fusion and intraoperative dosimetry. The authors propose a computational motion compensation method for tomosynthesis-based reconstruction that enables 3D localization of prostate implants from C-arm images despite C-arm oscillation and sagging. METHODS Five C-arm images are captured by rotating the C-arm around its primary axis, while measuring its rotation angle using a protractor or the C-arm joint encoder. The C-arm images are processed to obtain binary seed-only images from which a volume of interest is reconstructed. The motion compensation algorithm, iteratively, compensates for 2D translational motion of the C-arm by maximizing the number of voxels that project on a seed projection in all of the images. This obviates the need for C-arm full pose tracking traditionally implemented using radio-opaque fiducials or external trackers. The proposed reconstruction method is tested in simulations, in a phantom study and on ten patient data sets. RESULTS In a phantom implanted with 136 dummy seeds, the seed detection rate was 100% with a localization error of 0.86 ± 0.44 mm (Mean ± STD) compared to CT. For patient data sets, a detection rate of 99.5% was achieved in approximately 1 min per patient. The reconstruction results for patient data sets were compared against an available matching-based reconstruction method and showed relative localization difference of 0.5 ± 0.4 mm. CONCLUSIONS The motion compensation method can successfully compensate for large C-arm motion without using radio-opaque fiducial or external trackers. Considering the efficacy of the algorithm, its successful reconstruction rate and low computational burden, the algorithm is feasible for clinical use.
Collapse
Affiliation(s)
- Ehsan Dehghan
- School of Computing, Queen's University, Kingston, Ontario, Canada
| | | | | | | | | | | | | | | |
Collapse
|
7
|
Lee J, Kuo N, Deguet A, Dehghan E, Song DY, Burdette EC, Prince JL. Intraoperative 3D reconstruction of prostate brachytherapy implants with automatic pose correction. Phys Med Biol 2011; 56:5011-27. [PMID: 21772077 PMCID: PMC3172706 DOI: 10.1088/0031-9155/56/15/022] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The success of prostate brachytherapy critically depends on delivering adequate dose to the prostate gland, and the capability of intraoperatively localizing implanted seeds provides potential for dose evaluation and optimization during therapy. REDMAPS is a recently reported algorithm that carries out seed localization by detecting, matching and reconstructing seeds in only a few seconds from three acquired x-ray images (Lee et al 2011 IEEE Trans. Med. Imaging 29 38-51). In this paper, we present an automatic pose correction (APC) process that is combined with REDMAPS to allow for both more accurate seed reconstruction and the use of images with relatively large pose errors. APC uses a set of reconstructed seeds as a fiducial and corrects the image pose by minimizing the overall projection error. The seed matching and APC are iteratively computed until a stopping condition is met. Simulations and clinical studies show that APC significantly improves the reconstructions with an overall average matching rate of ⩾99.4%, reconstruction error of ⩽0.5 mm, and the matching solution optimality of ⩾99.8%.
Collapse
Affiliation(s)
- Junghoon Lee
- Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD 21218, USA.
| | | | | | | | | | | | | |
Collapse
|
8
|
Dehghan E, Jain AK, Moradi M, Wen X, Morris WJ, Salcudean SE, Fichtinger G. Brachytherapy seed reconstruction with joint-encoded C-arm single-axis rotation and motion compensation. Med Image Anal 2011; 15:760-71. [PMID: 21715214 DOI: 10.1016/j.media.2011.05.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Revised: 05/24/2011] [Accepted: 05/30/2011] [Indexed: 11/26/2022]
Abstract
C-arm fluoroscopy images are frequently used for qualitative assessment of prostate brachytherapy. Three-dimensional seed reconstruction from C-arm images is necessary for intraoperative dosimetry and quantitative assessment. Seed reconstruction requires accurately known C-arm poses. We propose to measure the C-arm rotation angles and computationally compensate for inevitable C-arm motion to compute the pose. We compensate the translational motions of a C-arm, such as oscillation, sagging and wheel motion using a three-level optimization algorithm and obviate the need for full pose tracking using external trackers or fiducials. We validated our approach on simulated and 100 clinical data sets from 10 patients and gained on average, a seed matching rate of 98.5%, projection error of 0.33 mm (STD=0.21 mm) and computation time of 19.8s per patient, which must be considered as clinically excellent results. We also show that without motion compensation the reconstruction is likely to fail.
Collapse
Affiliation(s)
- Ehsan Dehghan
- School of Computing, Queen's University, Kingston, ON, Canada.
| | | | | | | | | | | | | |
Collapse
|
9
|
Chng N, Spadinger I, Morris WJ, Usmani N, Salcudean S. Prostate brachytherapy postimplant dosimetry: Automatic plan reconstruction of stranded implants. Med Phys 2010; 38:327-42. [DOI: 10.1118/1.3525839] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
10
|
Su Y, Davis BJ, Furutani KM, Herman MG, Robb RA. Seed localization and TRUS-fluoroscopy fusion for intraoperative prostate brachytherapy dosimetry. ACTA ACUST UNITED AC 2010; 12:25-34. [PMID: 17364656 DOI: 10.3109/10929080601168239] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To develop and evaluate an integrated approach to intra-operative dosimetry for permanent prostate brachytherapy (PPB) by combining a fluoroscopy-based seed localization routine with a transrectal ultrasound (TRUS)-to-fluoroscopy fusion technique. MATERIALS AND METHODS Three-dimensional seed coordinates are reconstructed based on the two-dimensional seed locations identified from three fluoroscopic images acquired at different angles. A seed-based registration approach was examined in both simulation and phantom studies to register the seed locations identified from the fluoroscopic images to the TRUS images. Dose parameters were then evaluated and compared to CT-based dosimetry from a patient dataset. RESULTS Less than 0.2% error in the D90 value was observed using the TRUS-fluoroscopy image-fusion-based method relative to the CT-based post-implantation dosimetry. In the phantom study, an average distance of 3 mm was observed between the seeds identified from TRUS and the reconstructed seeds at registration. Isodose contours were displayed superimposed on the TRUS images. CONCLUSIONS Promising results were observed in this preliminary study of a TRUS-fluoroscopy fusion-based brachytherapy dosimetry analysis method, suggesting that the method is highly sensitive and calculates clinically relevant dosimetry, including the prostate D90. Further validation of the method is required for eventual clinical application.
Collapse
Affiliation(s)
- Yi Su
- Biomedical Imaging Resource, Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA
| | | | | | | | | |
Collapse
|
11
|
Brunet-Benkhoucha M, Verhaegen F, Lassalle S, Béliveau-Nadeau D, Reniers B, Donath D, Taussky D, Carrier JF. Clinical implementation of a digital tomosynthesis-based seed reconstruction algorithm for intraoperative postimplant dose evaluation in low dose rate prostate brachytherapy. Med Phys 2009; 36:5235-44. [DOI: 10.1118/1.3245888] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
12
|
Mitri FG, Davis BJ, Urban MW, Alizad A, Greenleaf JF, Lischer GH, Wilson TM, Fatemi M. Vibro-acoustography imaging of permanent prostate brachytherapy seeds in an excised human prostate--preliminary results and technical feasibility. ULTRASONICS 2009; 49:389-94. [PMID: 19062061 PMCID: PMC2715013 DOI: 10.1016/j.ultras.2008.10.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Revised: 09/23/2008] [Accepted: 10/20/2008] [Indexed: 05/16/2023]
Abstract
OBJECTIVE The objective in this work is to investigate the feasibility of using a new imaging tool called vibro-acoustography (VA) as a means of permanent prostate brachytherapy (PPB) seed localization to facilitate post-implant dosimetry (PID). METHODS AND MATERIALS Twelve OncoSeed (standard) and eleven EchoSeed (echogenic) dummy seeds were implanted in a human cadaver prostate. Seventeen seeds remained after radical retropubic prostatectomy. VA imaging was conducted on the prostate that was cast in a gel phantom and placed in a tank of degassed water. 2-D magnitude and phase VA image slices were obtained at different depths within the prostate showing location and orientation of the seeds. RESULTS VA demonstrates that twelve of seventeen (71%) seeds implanted were visible in the VA image, and the remainder were obscured by intra-prostatic calcifications. Moreover, it is shown here that VA is capable of imaging and locating PPB seeds within the prostate independent of seed orientation, and the resulting images are speckle free. CONCLUSION The results presented in this research show that VA allows seed detection within a human prostate regardless of their orientation, as well as imaging intra-prostatic calcifications.
Collapse
Affiliation(s)
- F G Mitri
- Mayo Clinic College of Medicine, Department of Physiology and Biomedical Engineering, Ultrasound Research Laboratory, Rochester, MN 55905, USA.
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Fatemi M, Mitri FG. Vibro-acoustography imaging applications for the prostate. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2009; 2009:4415-4419. [PMID: 19964365 DOI: 10.1109/iembs.2009.5333695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Vibro-acoustography (VA) is a novel modality that has shown significant features in imaging hard inclusions and inhomogeneities within biological tissue. Here we focus on its applications for prostate imaging as well as some of its related feasibility studies to guide minimally-invasive therapies such as brachytherapy and cryosurgery.
Collapse
Affiliation(s)
- Mostafa Fatemi
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, MN 55905 USA.
| | | |
Collapse
|
14
|
Lee J, Liu X, Jain AK, Prince JL, Fichtinger G. TOMOSYNTHESIS-BASED RADIOACTIVE SEED LOCALIZATION IN PROSTATE BRACHYTHERAPY USING MODIFIED DISTANCE MAP IMAGES. PROCEEDINGS. IEEE INTERNATIONAL SYMPOSIUM ON BIOMEDICAL IMAGING 2008:680-683. [PMID: 20066153 DOI: 10.1109/isbi.2008.4541087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We have developed a tomosynthesis-based radioactive seed localization method for prostate brachytherapy. In contrast to the projection image-based matching approach, our method does not involve explicit segmentation of seeds and can recover hidden seeds. Modified distance map images are computed from a limited number of x-ray projection images, and are backprojected to reconstuct a 3-D volume of interest. Candidate seed locations are extracted from the reconstructed volume and false positive seeds are eliminated by solving an optimal geometry coverage problem. The simulation results indicate that the implanted seed locations can be estimated from three or four images depending on the number of seeds if the pose of a C-arm is known. The algorithm was validated using phantom and clinical patient data.
Collapse
Affiliation(s)
- Junghoon Lee
- Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, USA
| | | | | | | | | |
Collapse
|
15
|
Tutar IB, Gong L, Narayanan S, Pathak SD, Cho PS, Wallner K, Kim Y. Seed-based transrectal ultrasound-fluoroscopy registration method for intraoperative dosimetry analysis of prostate brachytherapy. Med Phys 2008; 35:840-8. [DOI: 10.1118/1.2836422] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
16
|
Jain A, Deguet A, Iordachita I, Chintalapani G, Blevins J, Le Y, Armour E, Burdette C, Song D, Fichtinger G. Intra-operative 3D guidance in prostate brachytherapy using a non-isocentric C-arm. MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION : MICCAI ... INTERNATIONAL CONFERENCE ON MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION 2008; 10:9-17. [PMID: 18044547 DOI: 10.1007/978-3-540-75759-7_2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Intra-operative guidance in Transrectal Ultrasound (TRUS) guided prostate brachytherapy requires localization of inserted radioactive seeds relative to the prostate. Seeds were reconstructed using a typical C-arm, and exported to a commercial brachytherapy system for dosimetry analysis. Technical obstacles for 3D reconstruction on a non-isocentric C-arm included pose-dependent C-arm calibration; distortion correction; pose estimation of C-arm images; seed reconstruction; and C-arm to TRUS registration. In precision-machined hard phantoms with 40-100 seeds, we correctly reconstructed 99.8% seeds with a mean 3D accuracy of 0.68 mm. In soft tissue phantoms with 45-87 seeds and clinically realistic 15 degrees C-arm motion, we correctly reconstructed 100% seeds with an accuracy of 1.3 mm. The reconstructed 3D seed positions were then registered to the prostate segmented from TRUS. In a Phase-1 clinical trial, so far on 4 patients with 66-84 seeds, we achieved intra-operative monitoring of seed distribution and dosimetry. We optimized the 100% prescribed iso-dose contour by inserting an average of 3.75 additional seeds, making intra-operative dosimetry possible on a typical C-arm, at negligible additional cost to the existing clinical installation.
Collapse
Affiliation(s)
- A Jain
- Johns Hopkins University, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Su Y, Davis BJ, Furutani KM, Herman MG, Robb RA. Prostate brachytherapy seed reconstruction using an adaptive grouping technique. Med Phys 2007; 34:2975-84. [PMID: 17822006 DOI: 10.1118/1.2745936] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Fluoroscopy-based three-dimensional seed localization as a component of intraoperative dosimetry for prostate brachytherapy is an active area of research. A novel adaptive-grouping-based reconstruction approach is developed. This approach can recover overlapped seeds that are not detected from the fluoroscopic images. Two versions of the adaptive-grouping-based reconstruction approach are implemented and compared to an epipolar geometry-based seed reconstruction technique. Simulations based on nine patient datasets are used to validate the algorithms. A total of 2259 reconstructions is performed in which different types of error such as random noise in seed image locations and ambiguities in projection geometry are incorporated. Among those reconstructions, nine of the cases with overlapping seeds and the different types of error are performed. It is demonstrated that the adaptive-grouping-based reconstruction method is more accurate than the epipolar geometry method and allows faster reconstruction. At a random noise level of 0.6 mm, the mean distance error in reconstructed seed locations is approximately 1.0 mm for one of the relevant cases examined in detail. The best adaptive-grouping-based approach successfully recovered overlapped seeds in the majority of simulated cases (89%), with the remainder of cases generating one false positive seed. Phantom validation is also performed, and overlapped seeds are successfully recovered with all 92 seeds correctly localized and reconstructed. The mean distance error between segmented seed images and projected seeds is 0.5 mm in the phantom study.
Collapse
Affiliation(s)
- Yi Su
- Department of Physiology and Biomedical Engineering, Biomedical Imaging Resource, Mayo Clinic College of Medicine, Rochester Minnesota 55905, USA
| | | | | | | | | |
Collapse
|
18
|
Su Y, Davis BJ, Furutani KM, Herman MG, Robb RA. Dosimetry accuracy as a function of seed localization uncertainty in permanent prostate brachytherapy: increased seed number correlates with less variability in prostate dosimetry. Phys Med Biol 2007; 52:3105-19. [PMID: 17505092 DOI: 10.1088/0031-9155/52/11/012] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The variation of permanent prostate brachytherapy dosimetry as a function of seed localization uncertainty was investigated for I-125 implants with seed activities commonly employed in contemporary practice. Post-implant imaging and radiation dosimetry data from nine patients who underwent permanent prostate brachytherapy served as the source of clinical data for this simulation study. Gaussian noise with standard deviations ranging from 0.5 to 10 mm was applied to the seed coordinates for each patient dataset and 1000 simulations were performed at each noise level. Dose parameters, including D90, were computed for each case and compared with the actual dosimetry data. A total of 81 000 complete sets of post-brachytherapy dose volume statistics were computed. The results demonstrated that less than 5% deviation of prostate D90 can be expected when the seed localization uncertainty is 2 mm, whereas a seed localization uncertainty of 10 mm yielded an average decrease in D90 of 33 Gy. The mean normalized decrement in the prostate V100 was 10% at 5 mm uncertainty. Implants with greater seed number and larger prostate volume correlated with less sensitivity of D90 and V100 to seed localization uncertainty. Estimated target volume dose parameters tended to decrease with increasing seed localization uncertainty. The bladder V100 varied more significantly both in mean and standard deviation as compared to the urethra V100. A larger number of implanted seeds also correlated to less sensitivity of the bladder V100 to seed localization uncertainty. In contrast, the deviation of urethra V100 did not correlate with the number of implanted seeds or prostate volume.
Collapse
Affiliation(s)
- Yi Su
- Biomedical Imaging Resource, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | | | | | | | | |
Collapse
|
19
|
Salembier C, Lavagnini P, Nickers P, Mangili P, Rijnders A, Polo A, Venselaar J, Hoskin P. Tumour and target volumes in permanent prostate brachytherapy: A supplement to the ESTRO/EAU/EORTC recommendations on prostate brachytherapy. Radiother Oncol 2007; 83:3-10. [PMID: 17321620 DOI: 10.1016/j.radonc.2007.01.014] [Citation(s) in RCA: 228] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2006] [Revised: 01/17/2007] [Accepted: 01/29/2007] [Indexed: 11/26/2022]
Abstract
The aim of this paper is to supplement the GEC/ESTRO/EAU recommendations for permanent seed implantations in prostate cancer to develop consistency in target and volume definition for permanent seed prostate brachytherapy. Recommendations on target and organ at risk (OAR) definitions and dosimetry parameters to be reported on post implant planning are given.
Collapse
Affiliation(s)
- Carl Salembier
- Department of Radiation Oncology, Europe Hospitals, Brussels, Belgium
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Liu X, Jain AK, Fichtinger G. Prostate implant reconstruction with discrete tomography. MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION : MICCAI ... INTERNATIONAL CONFERENCE ON MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION 2007; 10:734-742. [PMID: 18051124 DOI: 10.1007/978-3-540-75757-3_89] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We developed a discrete tomography method for prostate implant reconstructions using only a limited number of X-ray projection images. A 3D voxel volume is reconstructed by back-projection and using distance maps generated from the projection images. The true seed locations are extracted from the voxel volume while false positive seeds are eliminated using a novel optimal geometry coverage model. The attractive feature of our method is that it does not require exact seed segmentation of the X-ray images and it yields near 100% correct reconstruction from only six images with an average reconstruction accuracy of 0.86 mm (std = 0.46mm).
Collapse
Affiliation(s)
- Xiaofeng Liu
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, USA
| | | | | |
Collapse
|
21
|
Wei Z, Gardi L, Downey DB, Fenster A. Automated localization of implanted seeds in 3D TRUS images used for prostate brachytherapy. Med Phys 2006; 33:2404-17. [PMID: 16898443 DOI: 10.1118/1.2207132] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
An algorithm has been developed in this paper to localize implanted radioactive seeds in 3D ultrasound images for a dynamic intraoperative brachytherapy procedure. Segmentation of the seeds is difficult, due to their small size in relatively low quality of transrectal ultrasound (TRUS) images. In this paper, intraoperative seed segmentation in 3D TRUS images is achieved by performing a subtraction of the image before the needle has been inserted, and the image after the seeds have been implanted. The seeds are searched in a "local" space determined by the needle position and orientation information, which are obtained from a needle segmentation algorithm. To test this approach, 3D TRUS images of the agar and chicken tissue phantoms were obtained. Within these phantoms, dummy seeds were implanted. The seed locations determined by the seed segmentation algorithm were compared with those obtained from a volumetric cone-beam flat-panel micro-CT scanner and human observers. Evaluation of the algorithm showed that the rms error in determining the seed locations using the seed segmentation algorithm was 0.98 mm in agar phantoms and 1.02 mm in chicken phantoms.
Collapse
Affiliation(s)
- Zhouping Wei
- Imaging Research Laboratories, Robarts Research Institute, London, ON N6A 5K8, Canada
| | | | | | | |
Collapse
|