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Radiofrequency ablation with the real-time virtual sonography system for treating hepatocellular carcinoma difficult to detect by ultrasonography.

Kawasoe H, Eguchi Y, Mizuta T, Yasutake T, Ozaki I, Shimonishi T, Miyazaki K, Tamai T, Kato A, Kudo S, Fujimoto K - J Clin Biochem Nutr (2007)

Bottom Line: The average nodule diameter was 2.4 +/- 1.6 cm, and punctures and coagulation were performed an average of 2.2 and 3 times per session.Dynamic CT after session confirmed effective coagulation of each nodule.In conclusion, this study demonstrates that the present system is capable of effectively and accurately treating tumors difficult to detect by conventional ultrasonography.

View Article: PubMed Central - PubMed

Affiliation: Department of Internal Medicine, Saga Medical School, 5-1-1, Nabeshima, Saga 849-8501, Japan.

ABSTRACT
Radiofrequency ablation has been applied to treat hepatocellular carcinoma, with favorable therapeutic outcomes. Nevertheless, practitioners have approached radiofrequency ablation with some reluctance due to the difficulty of identifying isoechoic tumors and recurrent tumors. The aim of the present study is to investigate the efficacy of Real-time Virtual Sonography to treat hepatocellular carcinoma difficult to detect by conventional ultrasonography. Real-time Virtual Sonography is a system generating multiplanar reconstruction images in real-time using the Hitachi medico EUB-8500 equipped with a probe. The system included following components: 1) digital imaging and communications in medicine (DICOM) data from dynamic CT, 2) a magnetic field generator to match the multiplanar reconstruction image on the monitor and the actual ultrasonography image, 3) the cross section with the tumor displayed as a multiplanar reconstruction image. Total twenty-five nodules of twenty-one patients underwent radiofrequency ablation monitored by Real-time Virtual Sonography. All nodules difficult to detect via conventional ultrasonography were clearly visualized in real-time. The average nodule diameter was 2.4 +/- 1.6 cm, and punctures and coagulation were performed an average of 2.2 and 3 times per session. Dynamic CT after session confirmed effective coagulation of each nodule. In conclusion, this study demonstrates that the present system is capable of effectively and accurately treating tumors difficult to detect by conventional ultrasonography.

No MeSH data available.


Related in: MedlinePlus

Summary of the Real-time Virtual Sonography system (Hitachi Medical, partially modified). Step 1: Using the xiphoid process as a reference point, match positional coordinates for positional synchronization. Step 2: Gather positional information from the magnetic sensor attached to the probe. Step 3: An MPR image matching the positional information from the probe is reconstructed based on CT volume data and displayed on the workstation monitor.A: Magnetic field generator. B: Magnetic sensor. C: Probe. D: Magnetic position detecting unit.
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Figure 1: Summary of the Real-time Virtual Sonography system (Hitachi Medical, partially modified). Step 1: Using the xiphoid process as a reference point, match positional coordinates for positional synchronization. Step 2: Gather positional information from the magnetic sensor attached to the probe. Step 3: An MPR image matching the positional information from the probe is reconstructed based on CT volume data and displayed on the workstation monitor.A: Magnetic field generator. B: Magnetic sensor. C: Probe. D: Magnetic position detecting unit.

Mentions: The therapeutic system used comprised the Hitachi Medico Digital Ultrasound EUB-8500 and Hitachi Medico Workstation RVS (Hitachi Medico. co. Tokyo, Japan), which generate real-time MPR images. The RVS, a revolutionary real-time MPR imaging machine that supports ultrasonography diagnosis developed by Hitachi Medico, consists of a small magnetic sensor attached to a convex-shaped EUB-8500 probe. This magnetic sensor precisely and consistently captures changes in magnetic fields generated by the generator placed on the left flank of a patient and detects the changes in the location, direction, and rotation of the probe scanning of the patient. The RVS instantaneously processes changes in positional information detected by the magnetic sensor and generates real-time MPR images matching cross-sectional images of the abdomen captured by the probe (Fig. 1). The actual procedure is as follows: 1) CTAP/CTHA was performed, followed by transfer of volume data (DICOM data) to the RVS. CTAP data was used because CTAP detects portal and hepatic veins, which was captured by ultrasonography. The positional relationship of a tumor to these vessels is critical for identifying lesions which ultrasonography cannot detect. 2) A magnetic field generator is placed on the left flank of a patient. 3) The sagittal section of the left hepatic lobe is first captured using a probe equipped with a magnetic sensor. The xiphoid process serves as the initial reference point. When a CT image with the tip of the xiphoid process captured before MPR processing matches the tip of the xiphoid process on the actual abdominal ultrasound image, the RVS begins continuous generation of MPR images in real-time, displaying the images on the workstation monitor. 4) A cross-sectional image showing the tumor is displayed with the MPR image, and both images are corrected based on neighboring portal and hepatic veins; and 5) the tumor is then punctured and coagulated under RVS-guidance in the conventional technique. The RFA device used in the methods were Cool-tip electrode with a 2- or 3-cm exposed tip and a radiofrequency generator (Radionics, Burlington, MA). The procedures were each performed by one of three experienced RFA physicians (Y.E, T.Y, and T.M).


Radiofrequency ablation with the real-time virtual sonography system for treating hepatocellular carcinoma difficult to detect by ultrasonography.

Kawasoe H, Eguchi Y, Mizuta T, Yasutake T, Ozaki I, Shimonishi T, Miyazaki K, Tamai T, Kato A, Kudo S, Fujimoto K - J Clin Biochem Nutr (2007)

Summary of the Real-time Virtual Sonography system (Hitachi Medical, partially modified). Step 1: Using the xiphoid process as a reference point, match positional coordinates for positional synchronization. Step 2: Gather positional information from the magnetic sensor attached to the probe. Step 3: An MPR image matching the positional information from the probe is reconstructed based on CT volume data and displayed on the workstation monitor.A: Magnetic field generator. B: Magnetic sensor. C: Probe. D: Magnetic position detecting unit.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2291506&req=5

Figure 1: Summary of the Real-time Virtual Sonography system (Hitachi Medical, partially modified). Step 1: Using the xiphoid process as a reference point, match positional coordinates for positional synchronization. Step 2: Gather positional information from the magnetic sensor attached to the probe. Step 3: An MPR image matching the positional information from the probe is reconstructed based on CT volume data and displayed on the workstation monitor.A: Magnetic field generator. B: Magnetic sensor. C: Probe. D: Magnetic position detecting unit.
Mentions: The therapeutic system used comprised the Hitachi Medico Digital Ultrasound EUB-8500 and Hitachi Medico Workstation RVS (Hitachi Medico. co. Tokyo, Japan), which generate real-time MPR images. The RVS, a revolutionary real-time MPR imaging machine that supports ultrasonography diagnosis developed by Hitachi Medico, consists of a small magnetic sensor attached to a convex-shaped EUB-8500 probe. This magnetic sensor precisely and consistently captures changes in magnetic fields generated by the generator placed on the left flank of a patient and detects the changes in the location, direction, and rotation of the probe scanning of the patient. The RVS instantaneously processes changes in positional information detected by the magnetic sensor and generates real-time MPR images matching cross-sectional images of the abdomen captured by the probe (Fig. 1). The actual procedure is as follows: 1) CTAP/CTHA was performed, followed by transfer of volume data (DICOM data) to the RVS. CTAP data was used because CTAP detects portal and hepatic veins, which was captured by ultrasonography. The positional relationship of a tumor to these vessels is critical for identifying lesions which ultrasonography cannot detect. 2) A magnetic field generator is placed on the left flank of a patient. 3) The sagittal section of the left hepatic lobe is first captured using a probe equipped with a magnetic sensor. The xiphoid process serves as the initial reference point. When a CT image with the tip of the xiphoid process captured before MPR processing matches the tip of the xiphoid process on the actual abdominal ultrasound image, the RVS begins continuous generation of MPR images in real-time, displaying the images on the workstation monitor. 4) A cross-sectional image showing the tumor is displayed with the MPR image, and both images are corrected based on neighboring portal and hepatic veins; and 5) the tumor is then punctured and coagulated under RVS-guidance in the conventional technique. The RFA device used in the methods were Cool-tip electrode with a 2- or 3-cm exposed tip and a radiofrequency generator (Radionics, Burlington, MA). The procedures were each performed by one of three experienced RFA physicians (Y.E, T.Y, and T.M).

Bottom Line: The average nodule diameter was 2.4 +/- 1.6 cm, and punctures and coagulation were performed an average of 2.2 and 3 times per session.Dynamic CT after session confirmed effective coagulation of each nodule.In conclusion, this study demonstrates that the present system is capable of effectively and accurately treating tumors difficult to detect by conventional ultrasonography.

View Article: PubMed Central - PubMed

Affiliation: Department of Internal Medicine, Saga Medical School, 5-1-1, Nabeshima, Saga 849-8501, Japan.

ABSTRACT
Radiofrequency ablation has been applied to treat hepatocellular carcinoma, with favorable therapeutic outcomes. Nevertheless, practitioners have approached radiofrequency ablation with some reluctance due to the difficulty of identifying isoechoic tumors and recurrent tumors. The aim of the present study is to investigate the efficacy of Real-time Virtual Sonography to treat hepatocellular carcinoma difficult to detect by conventional ultrasonography. Real-time Virtual Sonography is a system generating multiplanar reconstruction images in real-time using the Hitachi medico EUB-8500 equipped with a probe. The system included following components: 1) digital imaging and communications in medicine (DICOM) data from dynamic CT, 2) a magnetic field generator to match the multiplanar reconstruction image on the monitor and the actual ultrasonography image, 3) the cross section with the tumor displayed as a multiplanar reconstruction image. Total twenty-five nodules of twenty-one patients underwent radiofrequency ablation monitored by Real-time Virtual Sonography. All nodules difficult to detect via conventional ultrasonography were clearly visualized in real-time. The average nodule diameter was 2.4 +/- 1.6 cm, and punctures and coagulation were performed an average of 2.2 and 3 times per session. Dynamic CT after session confirmed effective coagulation of each nodule. In conclusion, this study demonstrates that the present system is capable of effectively and accurately treating tumors difficult to detect by conventional ultrasonography.

No MeSH data available.


Related in: MedlinePlus