1
|
Chen Y, Ge M, Ali R, Jiang H, Huang X, Qiu B. Quantitative MR thermometry based on phase-drift correction PRF shift method at 0.35 T. Biomed Eng Online 2018; 17:39. [PMID: 29631576 PMCID: PMC5892038 DOI: 10.1186/s12938-018-0472-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 03/30/2018] [Indexed: 11/30/2022] Open
Abstract
Background Noninvasive magnetic resonance thermometry (MRT) at low-field using proton resonance frequency shift (PRFS) is a promising technique for monitoring ablation temperature, since low-field MR scanners with open-configuration are more suitable for interventional procedures than closed systems. In this study, phase-drift correction PRFS with first-order polynomial fitting method was proposed to investigate the feasibility and accuracy of quantitative MR thermography during hyperthermia procedures in a 0.35 T open MR scanner. Methods Unheated phantom and ex vivo porcine liver experiments were performed to evaluate the optimal polynomial order for phase-drift correction PRFS. The temperature estimation approach was tested in brain temperature experiments of three healthy volunteers at room temperature, and in ex vivo porcine liver microwave ablation experiments. The output power of the microwave generator was set at 40 W for 330 s. In the unheated experiments, the temperature root mean square error (RMSE) in the inner region of interest was calculated to assess the best-fitting order for polynomial fit. For ablation experiments, relative temperature difference profile measured by the phase-drift correction PRFS was compared with the temperature changes recorded by fiber optic temperature probe around the microwave ablation antenna within the target thermal region. Results The phase-drift correction PRFS using first-order polynomial fitting could achieve the smallest temperature RMSE in unheated phantom, ex vivo porcine liver and in vivo human brain experiments. In the ex vivo porcine liver microwave ablation procedure, the temperature error between MRT and fiber optic probe of all but six temperature points were less than 2 °C. Overall, the RMSE of all temperature points was 1.49 °C. Conclusions Both in vivo and ex vivo experiments showed that MR thermometry based on the phase-drift correction PRFS with first-order polynomial fitting could be applied to monitor temperature changes during microwave ablation in a low-field open-configuration whole-body MR scanner.
Collapse
Affiliation(s)
- Yuping Chen
- Centers for Biomedical Engineering, University of Science and Technology of China, Hefei, 230026, Anhui, China
| | - Mengke Ge
- Centers for Biomedical Engineering, University of Science and Technology of China, Hefei, 230026, Anhui, China
| | - Rizwan Ali
- Centers for Biomedical Engineering, University of Science and Technology of China, Hefei, 230026, Anhui, China
| | - Hejun Jiang
- Centers for Biomedical Engineering, University of Science and Technology of China, Hefei, 230026, Anhui, China
| | - Xiaoyan Huang
- Centers for Biomedical Engineering, University of Science and Technology of China, Hefei, 230026, Anhui, China
| | - Bensheng Qiu
- Centers for Biomedical Engineering, University of Science and Technology of China, Hefei, 230026, Anhui, China.
| |
Collapse
|
2
|
Sabharwal T, Katsanos K, Buy X, Gangi A. Image-guided ablation therapy of bone tumors. Semin Ultrasound CT MR 2009; 30:78-90. [PMID: 19358439 DOI: 10.1053/j.sult.2008.12.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
A wide range of thermal and cryoablation methods is currently available for the curative eradication or palliative treatment of a variety of bone and soft-tissue tumors. Radiofrequency ablation has been developed as a multipurpose tool for the skeletal system. Cryoablation has the added advantages of direct computed tomography or magnetic resonance visualization and monitoring of treatment outcome with less peri- and postoperative pain. Use of appropriate thermo-sensors and insulation techniques, like carbon dioxide insufflation, results in enhanced safety and efficacy. Ablation of weight-bearing bones has to be supplemented with cement consolidation. The authors present an overview of the current status of percutaneous image-guided ablation therapy of bone and soft-tissue tumors, analyze the merits and limitations of the various systems available, and discuss possible new applications for the future.
Collapse
Affiliation(s)
- Tarun Sabharwal
- Department of Interventional Radiology, Guy's and St. Thomas' Hospital, 1st Floor, Lambeth Wing, Lambeth Palace Road, London SE1 7EH, UK
| | | | | | | |
Collapse
|
3
|
Moser T, Buy X, Goyault G, Tok CH, Irani F, Gangi A. [Image-guided ablation of bone tumors: review of current techniques]. ACTA ACUST UNITED AC 2008; 89:461-71. [PMID: 18477952 DOI: 10.1016/s0221-0363(08)71449-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Multiple interventional radiology techniques are available for percutaneous ablation of bone tumors: alcohol, laser, radiofrequency, microwave, ultrasound, and cryogenic ablation. Several indications have already been validated, including radiofrequency ablation of osteoid osteoma and bone metastases, with results superior to conventional treatment. More indications should be added over the coming years. The purpose of this article is to review the principles of the different ablation techniques, summarize their respective indications and results and discuss their implementation and the eventual combination with cementoplasty techniques.
Collapse
Affiliation(s)
- T Moser
- Service de Radiologie B, CHU Strasbourg, Hôpital Civil, Strasbourg Cedex, France.
| | | | | | | | | | | |
Collapse
|
4
|
Lazebnik RS, Weinberg BD, Breen MS, Lewin JS, Wilson DL. Semiautomatic parametric model-based 3D lesion segmentation for evaluation of MR-guided radiofrequency ablation therapy. Acad Radiol 2005; 12:1491-501. [PMID: 16321737 DOI: 10.1016/j.acra.2005.07.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2005] [Revised: 07/20/2005] [Accepted: 07/23/2005] [Indexed: 10/25/2022]
Abstract
RATIONALE AND OBJECTIVES Interventional magnetic resonance imaging (iMRI) allows real-time guidance and optimization of radiofrequency ablation of pathologic tissue. For many tissues, resulting lesions have a characteristic two-boundary appearance featuring an inner region and an outer hyper-intense margin in both T2 and contrast-enhanced (CE) T1-weighted MR images. We created a geometric model-based semiautomatic method to aid in real-time lesion segmentation, cross-sectional/three-dimensional visualization, and intra/posttreatment evaluation. MATERIALS AND METHODS Our method relies on a 12-parameter, 3-dimensional, globally deformable model with quadric surfaces that describe both lesion boundaries. We present an energy minimization approach to quickly and semiautomatically fit the model to a gray-scale MR image volume. We applied the method to in vivo lesions (n = 10) in a rabbit thigh model, using T2 and CE T1-weighted MR images, and compared the results with manually segmented boundaries. RESULTS For all lesions, the median error was < or =1.21 mm for the inner region and < or =1.00 mm for the outer hyper-intense region, values that favorably compare to a voxel width of 0.7 mm and distances between the borders manually segmented by the two operators. CONCLUSION Our method provides a precise, semiautomatic approximation of lesion shape for ellipsoidal lesions. Further, the method has clinical applications in lesion visualization, volume estimation, and treatment evaluation.
Collapse
Affiliation(s)
- Roee S Lazebnik
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
| | | | | | | | | |
Collapse
|
5
|
Tsetis DK, Michalis LK, Rees MR, Katsamouris AN, Matsagas MI, Katsouras CS, Sideris DA, Gourtsoyiannis NC. Vibrational angioplasty in the treatment of chronic infrapopliteal arterial occlusions: preliminary experience. J Endovasc Ther 2002; 9:889-95. [PMID: 12546592 DOI: 10.1177/152660280200900624] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE To evaluate the safety and efficacy of vibrational angioplasty in chronic infrapopliteal arterial occlusions. METHODS Twelve patients (9 men, aged 54 to 90 years) with 13 below-knee arterial chronic total occlusions were treated percutaneously using vibrational angioplasty. The occlusions were located in the anterior tibial artery (n=5), the tibioperoneal trunk (n=4), the peroneal artery (n=1), the posterior tibial artery (n=1), and in both the tibioperoneal trunk and peroneal artery (n=2). The length of the lesions ranged from 5 to 14 cm. RESULTS Recanalization was successful in 12 (92.3%) lesions. In 1 case, the wire perforated the arterial wall; the procedure was abandoned without clinical sequelae. The time to cross the occlusions with the wire ranged from 6 to 19 minutes. No other complications were observed. Clinical follow-up ranged to 18 months. Ten patients with ulceration or gangrene demonstrated good wound healing, and pain was alleviated in all successfully treated patients. CONCLUSIONS Vibrational angioplasty appears feasible as a means of safely recanalizing chronic total occlusions of the infrapopliteal arteries. Further experience should be acquired to assess its short- and long-term effects on this vascular territory.
Collapse
Affiliation(s)
- Dimitrios K Tsetis
- Department of Radiology, University Hospital of Heraklion, Crete, Greece
| | | | | | | | | | | | | | | |
Collapse
|
6
|
Lazebnik RS, Weinberg BD, Breen MS, Lewin JS, Wilson DL. Three-dimensional model of lesion geometry for evaluation of MR-guided thermal ablation therapy. Acad Radiol 2002; 9:1128-38. [PMID: 12385507 DOI: 10.1016/s1076-6332(03)80514-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
RATIONALE AND OBJECTIVES High-radiofrequency energy is used clinically to ablate pathologic tissue with interventional magnetic resonance (MR) imaging. For many tissues, resulting lesions have a characteristic appearance on contrast-enhanced T1- and T2-weighted MR images, with two boundaries enclosing an inner hypointense region and an outer hyperintense margin. Geometric modeling of three-dimensional thermal lesions in animal experiments and patient treatments would improve analyses and visualization. MATERIALS AND METHODS The authors created a model with two quadric surfaces and 12 parameters to describe both lesion surfaces. Parameters were estimated with iterative optimization to minimize the sum of the squared shortest distances from segmented points to the model surface. The authors validated the estimation process with digital lesion phantoms that simulated varying levels of segmentation error and missing surface information. They also applied their method to in vivo images of lesions in a rabbit model. RESULTS For simulated phantom lesions, the lesion geometry was accurate despite manual segmentation error and incomplete surface data. Even when 50% of the surface was missing, the median error was less than 0.5 mm. For all in vivo lesions, the median distance from the model surface to data was no more than 0.58 mm for both inner and outer surfaces, less than a voxel width (0.7 mm). The interquartile range was 0.89 mm or less for all data. CONCLUSION The authors' model provides a good approximation of actual lesion geometry and is highly resistant to missing segmentation information. It should prove useful for three-dimensional lesion visualization, volume estimation, automated segmentation, and volume registration.
Collapse
Affiliation(s)
- Roee S Lazebnik
- Department of Biomedical Engineering, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
| | | | | | | | | |
Collapse
|
7
|
Gould SWT, Martin S, Agarwal T, Patel B, Gedroyc W, Darzi A. Image-guided surgery for anal fistula in a 0.5T interventional MRI unit. J Magn Reson Imaging 2002; 16:267-76. [PMID: 12205582 DOI: 10.1002/jmri.10158] [Citation(s) in RCA: 12] [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
PURPOSE To determine whether MR-guided anorectal surgery is feasible, and to develop techniques for MR-guided anal fistula surgery. MATERIALS AND METHODS Six patients with pilonidal sinus (PNS), and 21 with suspected anal fistulae were operated on in the GE Signa SPIO 0.5T interventional MRI unit. Procedures were performed with magnet-safe Lockhart-Mummery fistula probes. Preprocedural and intra-operative MRI (IOMRI) techniques were used to identify the extent of the fistula tracts and septic foci, and to ensure the adequacy of the surgical procedure. RESULTS IOMRI demonstrated the PNS lesions and the adequacy of excision. Imaging failed to demonstrate a fistula in two patients, as confirmed by surgical examination. No images were obtained in one patient due to his size (weight in excess of 100 kg). In 18 patients a fistula tract or abscess was demonstrated and IOMRI was used to assess the adequacy of the surgical procedure. In three patients this demonstrated incomplete drainage of septic foci, which was not obvious on inspection of the surgical field. We believe that in these patients IOMRI prevented an incomplete procedure and the potential requirement for a second operation. Further surgery was performed to rectify this situation. The fistula tract was laid open in 13 patients, and a Seton drain was inserted in five. CONCLUSION MRI-guided surgery for anal fistula is feasible. IOMRI demonstrates the exact anatomy of the tracts and abscesses, and confirms that all have been adequately treated. We believe it may become particularly useful in surgery for recurrent and complex anal fistulae, and may lead to fewer recurrences.
Collapse
Affiliation(s)
- S W T Gould
- Academic Surgical Unit, St. Mary's Hospital, Imperial College of Science, Technology and Medicine, London, United Kingdom.
| | | | | | | | | | | |
Collapse
|
8
|
Gould SWT, Agarwal T, Benoist S, Patel B, Gedroyc W, Darzi A. Resection of soft tissue sarcomas with intra-operative magnetic resonance guidance. J Magn Reson Imaging 2002; 15:114-9. [PMID: 11793466 DOI: 10.1002/jmri.10037] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To report on a preliminary series of magnetic resonance (MR)-guided sarcoma resections. MATERIALS AND METHODS Three patients with the skin sarcoma dermatofibrosarcoma protuberans underwent MR-guided resection. RESULTS The extent of the tumor at MR imaging was greater in each case than suggested by clinical examination. Adequate resection margins were planned using short Tau inversion recovery (STIR) sequences and intra-operative imaging was used to confirm complete tumor excision. Histological examination confirmed clear surgical margins of at least 1 cm in each case. CONCLUSION We believe this technique may reduce the incidence of specimen margins positive for tumor following resection, and consequently reduce the need for further excisional surgery.
Collapse
Affiliation(s)
- Stuart William Thomas Gould
- Department of Surgical Oncology and Technology, Imperial College School of Medicine, Academic Surgical Unit, St. Mary's Hospital, London, UK.
| | | | | | | | | | | |
Collapse
|
9
|
Michalis LK, Tsetis DK, Katsamouris AN, Rees MR, Sideris DA, Gourtsoyiannis NC. Vibrational angioplasty in the treatment of chronic femoropopliteal arterial occlusions: preliminary experience. J Endovasc Ther 2001; 8:615-21. [PMID: 11797979 DOI: 10.1177/152660280100800615] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE To evaluate the safety and efficacy of vibrational angioplasty in chronic femoropopliteal arterial occlusions. METHODS Six patients (5 men; ages 52 to 84 years) with peripheral arterial occlusive disease were treated percutaneously using vibrational angioplasty to recanalize the lesion. Three occlusions ranging from 10 to 15 cm long were in the superficial femoral artery (SFA), while 3 other diffusely diseased popliteal arteries were occluded distally (length from 3.5 to 4.5 cm). Vibrational angioplasty using coronary equipment was applied to assist passage of a coronary guidewire, which was followed by conventional angioplasty. Follow-up surveillance featured periodic physical examination, ankle brachial index measurements, and duplex scanning. RESULTS In all 6 cases, recanalization of the occlusions was successful and without complications. The time to cross the occlusions with the wire ranged from 20 to 25 minutes for the SFA lesions and from 4 to 10 minutes for the popliteal occlusions. Two SFA occlusions were treated with stent implantation. Over a follow-up of 3 to 9 months, all treated vessels were patent. In 3 patients with skin ulcers, healing of the ulcers was observed. CONCLUSIONS Vibrational angioplasty using coronary guidewires seems to be a promising ancillary technique in the management of chronic femoropopliteal arterial occlusions.
Collapse
Affiliation(s)
- L K Michalis
- Department of Cardiology, University Hospital of Ioannina, Greece
| | | | | | | | | | | |
Collapse
|
10
|
Gould SW, Darzi A. The interventional magnetic resonance unit--the minimal access operating theatre of the future? Br J Radiol 1997; 70 Spec No:S89-97. [PMID: 9534722 DOI: 10.1259/bjr.1997.0012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Interventional magnetic resonance units give the surgeon the potential to use intraoperative imaging to guide the surgical procedure. The advantages of magnetic resonance (MR) over other intraoperative imaging modalities include excellent soft tissue resolution, lack of ionizing radiation and the ability to reconstruct images in any desired plane. Postulated advantages include the ability to confirm adequate tumour resection, reduction in procedure magnitude and complication rate, shortened inpatient stay and the development of novel minimally invasive techniques including the use of thermal energy to destroy lesions. Fully MR compatible anaesthetic and patient monitoring equipment is available. However, before the MR-guided minimally invasive surgery can become a reality, much work is required in the assessment and development of MR compatible surgical instrumentation and equipment. This review describes the testing and development of instruments and equipment for MR image-guided surgery that we have undertaken. We describe the techniques we employ for open and minimal access surgery within this unique environment. The difficulties of operating within such an environment and the safety issues that this engenders are discussed. The current applications of intraoperative MR in the main surgical specialities are reviewed, and possible future areas of development for MR-guided minimally invasive surgery described.
Collapse
Affiliation(s)
- S W Gould
- Minimal Access Surgical Unit, St Mary's Hospital, Paddington, London, UK
| | | |
Collapse
|