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Image Fusion for Radiosurgery, Neurosurgery and Hypofractionated Radiotherapy.

Inoue HK, Nakajima A, Sato H, Noda SE, Saitoh J, Suzuki Y - Cureus (2015)

Bottom Line: All images are fused and registered on thin sliced CT sections and exactly demarcated targets are planned for treatment.Follow-up images are also able to register on this CT.Exact target changes, including volume, are possible in this fusion system.

View Article: PubMed Central - HTML - PubMed

Affiliation: Dept of Neurosurgery and Radiation Oncology, Institute of Neural Organization and Cyber Center, Kanto Neurosurgical Hospital.

ABSTRACT
Precise target detection is essential for radiosurgery, neurosurgery and hypofractionated radiotherapy because treatment results and complication rates are related to accuracy of the target definition. In skull base tumors and tumors around the optic pathways, exact anatomical evaluation of cranial nerves are important to avoid adverse effects on these structures close to lesions. Three-dimensional analyses of structures obtained with MR heavy T2-images and image fusion with CT thin-sliced sections are desirable to evaluate fine structures during radiosurgery and microsurgery. In vascular lesions, angiography is most important for evaluations of whole structures from feeder to drainer, shunt, blood flow and risk factors of bleeding. However, exact sites and surrounding structures in the brain are not shown on angiography. True image fusions of angiography, MR images and CT on axial planes are ideal for precise target definition. In malignant tumors, especially recurrent head and neck tumors, biologically active areas of recurrent tumors are main targets of radiosurgery. PET scan is useful for quantitative evaluation of recurrences. However, the examination is not always available at the time of radiosurgery. Image fusion of MR diffusion images with CT is always available during radiosurgery and useful for the detection of recurrent lesions. All images are fused and registered on thin sliced CT sections and exactly demarcated targets are planned for treatment. Follow-up images are also able to register on this CT. Exact target changes, including volume, are possible in this fusion system. The purpose of this review is to describe the usefulness of image fusion for 1) skull base, 2) vascular, 3) recurrent target detection, and 4) follow-up analyses in radiosurgery, neurosurgery and hypofractionated radiotherapy.

No MeSH data available.


Related in: MedlinePlus

Measurement of tumor reduction rates.MR images fused to thin-sliced CT before radiosurgery (left). Follow-up MR images after treatment (right) also fused to CT (base on images taken during radiosurgey). Both images are able to compare with identical axial (upper line) and coronal (lower line) images using image fusion. The quantitative analysis (of the reduction rate) is also possible from the volume measurements taken before and after treatment (center).
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FIG13: Measurement of tumor reduction rates.MR images fused to thin-sliced CT before radiosurgery (left). Follow-up MR images after treatment (right) also fused to CT (base on images taken during radiosurgey). Both images are able to compare with identical axial (upper line) and coronal (lower line) images using image fusion. The quantitative analysis (of the reduction rate) is also possible from the volume measurements taken before and after treatment (center).

Mentions: Similarly, the quantitative analyses after treatment are used to evaluate the sensitivities for treatment and dose responses after treatment, etc. However, radiological examination using MR imaging is not always performed with the same machine and with patients in the same position, even when imaging is performed in the same hospital. Image fusion of such follow-up MR images to registered CT for radiosurgery enables the changes to be compared after treatment on the same axial images with identical angles. To accurately measure lesion volumes after treatment, the exact volume changes and reduction rates are available, as shown in Figure 13, even for small tumors. The rate is calculated as (volume before treatment – volume after treatment)/volume before treatment.


Image Fusion for Radiosurgery, Neurosurgery and Hypofractionated Radiotherapy.

Inoue HK, Nakajima A, Sato H, Noda SE, Saitoh J, Suzuki Y - Cureus (2015)

Measurement of tumor reduction rates.MR images fused to thin-sliced CT before radiosurgery (left). Follow-up MR images after treatment (right) also fused to CT (base on images taken during radiosurgey). Both images are able to compare with identical axial (upper line) and coronal (lower line) images using image fusion. The quantitative analysis (of the reduction rate) is also possible from the volume measurements taken before and after treatment (center).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4494462&req=5

FIG13: Measurement of tumor reduction rates.MR images fused to thin-sliced CT before radiosurgery (left). Follow-up MR images after treatment (right) also fused to CT (base on images taken during radiosurgey). Both images are able to compare with identical axial (upper line) and coronal (lower line) images using image fusion. The quantitative analysis (of the reduction rate) is also possible from the volume measurements taken before and after treatment (center).
Mentions: Similarly, the quantitative analyses after treatment are used to evaluate the sensitivities for treatment and dose responses after treatment, etc. However, radiological examination using MR imaging is not always performed with the same machine and with patients in the same position, even when imaging is performed in the same hospital. Image fusion of such follow-up MR images to registered CT for radiosurgery enables the changes to be compared after treatment on the same axial images with identical angles. To accurately measure lesion volumes after treatment, the exact volume changes and reduction rates are available, as shown in Figure 13, even for small tumors. The rate is calculated as (volume before treatment – volume after treatment)/volume before treatment.

Bottom Line: All images are fused and registered on thin sliced CT sections and exactly demarcated targets are planned for treatment.Follow-up images are also able to register on this CT.Exact target changes, including volume, are possible in this fusion system.

View Article: PubMed Central - HTML - PubMed

Affiliation: Dept of Neurosurgery and Radiation Oncology, Institute of Neural Organization and Cyber Center, Kanto Neurosurgical Hospital.

ABSTRACT
Precise target detection is essential for radiosurgery, neurosurgery and hypofractionated radiotherapy because treatment results and complication rates are related to accuracy of the target definition. In skull base tumors and tumors around the optic pathways, exact anatomical evaluation of cranial nerves are important to avoid adverse effects on these structures close to lesions. Three-dimensional analyses of structures obtained with MR heavy T2-images and image fusion with CT thin-sliced sections are desirable to evaluate fine structures during radiosurgery and microsurgery. In vascular lesions, angiography is most important for evaluations of whole structures from feeder to drainer, shunt, blood flow and risk factors of bleeding. However, exact sites and surrounding structures in the brain are not shown on angiography. True image fusions of angiography, MR images and CT on axial planes are ideal for precise target definition. In malignant tumors, especially recurrent head and neck tumors, biologically active areas of recurrent tumors are main targets of radiosurgery. PET scan is useful for quantitative evaluation of recurrences. However, the examination is not always available at the time of radiosurgery. Image fusion of MR diffusion images with CT is always available during radiosurgery and useful for the detection of recurrent lesions. All images are fused and registered on thin sliced CT sections and exactly demarcated targets are planned for treatment. Follow-up images are also able to register on this CT. Exact target changes, including volume, are possible in this fusion system. The purpose of this review is to describe the usefulness of image fusion for 1) skull base, 2) vascular, 3) recurrent target detection, and 4) follow-up analyses in radiosurgery, neurosurgery and hypofractionated radiotherapy.

No MeSH data available.


Related in: MedlinePlus