Colorectal cancer (CRC) represents one of the leading causes of tumor-related deaths worldwide. Among the various tools at physicians’ disposal for the diagnostic management of the disease, tomographic imaging (e.g.,...Colorectal cancer (CRC) represents one of the leading causes of tumor-related deaths worldwide. Among the various tools at physicians’ disposal for the diagnostic management of the disease, tomographic imaging (e.g., CT, MRI, and hybrid PET imaging) is considered essential. The qualitative and subjective evaluation of tomographic images is the main approach used to obtain valuable clinical information, although this strategy suffers from both intrinsic and operator-dependent limitations. More recently, advanced imaging techniques have been developed with the aim of overcoming these issues. Such techniques, such as diffusion-weighted MRI and perfusion imaging, were designed for the “in vivo” evaluation of specific biological tissue features in order to describe them in terms of quantitative parameters, which could answer questions difficult to address with conventional imaging alone (e.g., questions related to tissue characterization and prognosis). Furthermore, it has been observed that a large amount of numerical and statistical information is buried inside tomographic images, resulting in their invisibility during conventional assessment. This information can be extracted and represented in terms of quantitative parameters through different processes (e.g., texture analysis). Numerous researchers have focused their work on the significance of these quantitative imaging parameters for the management of CRC patients. In this review, we aimed to focus on evidence reported in the academic literature regarding the application of parametric imaging to the diagnosis, staging and prognosis of CRC while discussing future perspectives and present limitations. While the transition from purely anatomical to quantitative tomographic imaging appears achievable for CRC diagnostics, some essential milestones, such as scanning and analysis standardization and the definition of robust cut-off values, must be achieved before quantitative tomographic imaging can be incorporated into daily clinical practice.展开更多
Magnetic resonance (MR) imaging has been increasingly used in the evaluation of prostate cancer. As studies have suggested that the majority of cancers arise from the peripheral zone (PZ), MR imaging has focused on th...Magnetic resonance (MR) imaging has been increasingly used in the evaluation of prostate cancer. As studies have suggested that the majority of cancers arise from the peripheral zone (PZ), MR imaging has focused on the PZ of the prostate gland thus far. However, a considerable number of cancers (up to 30%) originate in the transition zone (TZ), substantially contributing to morbidity and mortality. Therefore, research is needed on the TZ of the prostate gland. Recently, MR imaging and advanced MR techniques have been gaining acceptance in evaluation of the TZ. In this article, the MR imaging features of TZ prostate cancers, the role of MR imaging in TZ cancer detection and staging, and recent advanced MR techniques will be discussed in light of the literature.展开更多
AIM: To evaluate the response of hepatocellular carcinoma (HCC) to transarterial chemoembolization (TACE) using a simplified protocol of parametric contrast-enhanced ultrasound (pCEUS). METHODS: Eighteen patients with...AIM: To evaluate the response of hepatocellular carcinoma (HCC) to transarterial chemoembolization (TACE) using a simplified protocol of parametric contrast-enhanced ultrasound (pCEUS). METHODS: Eighteen patients with HCC (18 target tumors, diameter: 2.8-12 cm) were evaluated before, and 20 d after TACE. The distribution and morphology of TACE-induced necrosis in these tumors precluded accurate evaluation by visual assessment or by simple measurements. For pCEUS, a 4.8 mL bolus of SonoVue (Bracco, Milan, Italy) was intravenously administered and analysis of tumor perfusion during the initial phase of enhancement (0-30 s post injection) was performed with dedicated software (Qontrast, Bracco, Milan, Italy). Time-intensity curves were plotted and three parameters were calculated: peak intensity (PI, in percentage %), time to peak (TTP in seconds, s) and area under the curve during wash-in (AUC-WI, in arbitrary units, a.u). Magnetic resonance imaging was the standard imaging modality for post-treatment evaluation. Changes in tumor size were recorded and response was assessed according to response evaluation criteria in solid tumors criteria. RESULTS: A statistically significant decrease in PI and AUC-WI was observed in the treated tumors post TACE; PIpre: 21.5% ± 8.7% (mean ± SD), PIpost: 12.7% ± 6.7%, P < 0.001, AUC-WI pre: 17493 ± 9563 a.u, AUC-WI post: 9585 ± 5494 a.u, P < 0.001. A slight increase in TTP was noted post TACE, but this was not statistically significant; TTP pre: 13.1 ± 4.3 s, TTP post: 13.6 ± 4.2 s , P = 0.058). The changes in the aforementioned parameters were not accompanied by significant tumor shrinkage. CONCLUSION: pCEUS, even when limited to the study of the arterial phase of tumoral enhancement, can detect and quantify early perfusional changes in HCC post TACE.展开更多
In patients with colorectal liver metastasis(CRLMs)unsuitable for surgery,oncological treatments,such as chemotherapy and targeted agents,can be performed.Cross-sectional imaging[computed tomography(CT),magnetic reson...In patients with colorectal liver metastasis(CRLMs)unsuitable for surgery,oncological treatments,such as chemotherapy and targeted agents,can be performed.Cross-sectional imaging[computed tomography(CT),magnetic resonance imaging(MRI),18-fluorodexoyglucose positron emission tomography with CT/MRI]evaluates the response of CRLMs to therapy,using post-treatment lesion shrinkage as a qualitative imaging parameter.This point is critical because the risk of toxicity induced by oncological treatments is not always balanced by an effective response to them.Consequently,there is a pressing need to define biomarkers that can predict treatment responses and estimate the likelihood of drug resistance in individual patients.Advanced quantitative imaging(diffusionweighted imaging,perfusion imaging,molecular imaging)allows the in vivo evaluation of specific biological tissue features described as quantitative parameters.Furthermore,radiomics can represent large amounts of numerical and statistical information buried inside cross-sectional images as quantitative parameters.As a result,parametric analysis(PA)translates the numerical data contained in the voxels of each image into quantitative parameters representative of peculiar neoplastic features such as perfusion,structural heterogeneity,cellularity,oxygenation,and glucose consumption.PA could be a potentially useful imaging marker for predicting CRLMs treatment response.This review describes the role of PA applied to cross-sectional imaging in predicting the response to oncological therapies in patients with CRLMs.展开更多
We report a framing imaging based on noncollinear optical parametric amplification(NCOPA),named FINCOPA,which applies NCOPA for the first time to single-shot ultrafast optical imaging.In an experiment targeting a lase...We report a framing imaging based on noncollinear optical parametric amplification(NCOPA),named FINCOPA,which applies NCOPA for the first time to single-shot ultrafast optical imaging.In an experiment targeting a laser-induced air plasma grating,FINCOPA achieved 50 fs-resolved optical imaging with a spatial resolution of^83 lp∕mm and an effective frame rate of 10 trillion frames per second(Tfps).It has also successfully visualized an ultrafast rotating optical field with an effective frame rate of 15 Tfps.FINCOPA has simultaneously a femtosecond-level temporal resolution and frame interval and a micrometer-level spatial resolution.Combining outstanding spatial and temporal resolutions with an ultrahigh frame rate,FINCOPA will contribute to high-spatiotemporal resolution observations of ultrafast transient events,such as atomic or molecular dynamics in photonic materials,plasma physics,and laser inertial-confinement fusion.展开更多
Applying an ultrafast vortex laser as the pump,optical parametric amplification can be used for spiral phase-contrast imaging with high gain,wide spatial bandwidth,and high imaging contrast.Our experiments show that t...Applying an ultrafast vortex laser as the pump,optical parametric amplification can be used for spiral phase-contrast imaging with high gain,wide spatial bandwidth,and high imaging contrast.Our experiments show that this design has realized the 1064 nm spiral phase-contrast idler imaging of biological tissues(frog egg cells and onion epidermis)with a spatial resolution at several microns level and a superior imaging contrast to both the traditional bright-or dark-field imaging under a weak illumination of 7 nW/cm^(2).This work provides a powerful way for biological tissue imaging in the second near-infrared region.展开更多
A weak infrared （IR） image amplifier with more than 60-dB optical gain and is developed from a picosecond （PS） 355-nm pumped gated optical parametric frequency up-conversion amplifier （OPA） in a/% BaB204 （BBO）...A weak infrared （IR） image amplifier with more than 60-dB optical gain and is developed from a picosecond （PS） 355-nm pumped gated optical parametric frequency up-conversion amplifier （OPA） in a/% BaB204 （BBO） crystal. The IR image at 1064 nm is amplified and up-converted into the visible region at 532 nm by parametric amplification and up-conversion. With the optimized optical gain, the lowest detectable energy of the image can be as low as 1.8 femto-Joule per pulse, which is three orders of magnitude lower than the detection limit of a charge-coupled device （CCD） camera. The transversal resolution of the OPA imaging is investigated, and the approaches for higher detection sensitivity and higher transversal resolution are proposed.展开更多
文摘Colorectal cancer (CRC) represents one of the leading causes of tumor-related deaths worldwide. Among the various tools at physicians’ disposal for the diagnostic management of the disease, tomographic imaging (e.g., CT, MRI, and hybrid PET imaging) is considered essential. The qualitative and subjective evaluation of tomographic images is the main approach used to obtain valuable clinical information, although this strategy suffers from both intrinsic and operator-dependent limitations. More recently, advanced imaging techniques have been developed with the aim of overcoming these issues. Such techniques, such as diffusion-weighted MRI and perfusion imaging, were designed for the “in vivo” evaluation of specific biological tissue features in order to describe them in terms of quantitative parameters, which could answer questions difficult to address with conventional imaging alone (e.g., questions related to tissue characterization and prognosis). Furthermore, it has been observed that a large amount of numerical and statistical information is buried inside tomographic images, resulting in their invisibility during conventional assessment. This information can be extracted and represented in terms of quantitative parameters through different processes (e.g., texture analysis). Numerous researchers have focused their work on the significance of these quantitative imaging parameters for the management of CRC patients. In this review, we aimed to focus on evidence reported in the academic literature regarding the application of parametric imaging to the diagnosis, staging and prognosis of CRC while discussing future perspectives and present limitations. While the transition from purely anatomical to quantitative tomographic imaging appears achievable for CRC diagnostics, some essential milestones, such as scanning and analysis standardization and the definition of robust cut-off values, must be achieved before quantitative tomographic imaging can be incorporated into daily clinical practice.
文摘Magnetic resonance (MR) imaging has been increasingly used in the evaluation of prostate cancer. As studies have suggested that the majority of cancers arise from the peripheral zone (PZ), MR imaging has focused on the PZ of the prostate gland thus far. However, a considerable number of cancers (up to 30%) originate in the transition zone (TZ), substantially contributing to morbidity and mortality. Therefore, research is needed on the TZ of the prostate gland. Recently, MR imaging and advanced MR techniques have been gaining acceptance in evaluation of the TZ. In this article, the MR imaging features of TZ prostate cancers, the role of MR imaging in TZ cancer detection and staging, and recent advanced MR techniques will be discussed in light of the literature.
文摘AIM: To evaluate the response of hepatocellular carcinoma (HCC) to transarterial chemoembolization (TACE) using a simplified protocol of parametric contrast-enhanced ultrasound (pCEUS). METHODS: Eighteen patients with HCC (18 target tumors, diameter: 2.8-12 cm) were evaluated before, and 20 d after TACE. The distribution and morphology of TACE-induced necrosis in these tumors precluded accurate evaluation by visual assessment or by simple measurements. For pCEUS, a 4.8 mL bolus of SonoVue (Bracco, Milan, Italy) was intravenously administered and analysis of tumor perfusion during the initial phase of enhancement (0-30 s post injection) was performed with dedicated software (Qontrast, Bracco, Milan, Italy). Time-intensity curves were plotted and three parameters were calculated: peak intensity (PI, in percentage %), time to peak (TTP in seconds, s) and area under the curve during wash-in (AUC-WI, in arbitrary units, a.u). Magnetic resonance imaging was the standard imaging modality for post-treatment evaluation. Changes in tumor size were recorded and response was assessed according to response evaluation criteria in solid tumors criteria. RESULTS: A statistically significant decrease in PI and AUC-WI was observed in the treated tumors post TACE; PIpre: 21.5% ± 8.7% (mean ± SD), PIpost: 12.7% ± 6.7%, P < 0.001, AUC-WI pre: 17493 ± 9563 a.u, AUC-WI post: 9585 ± 5494 a.u, P < 0.001. A slight increase in TTP was noted post TACE, but this was not statistically significant; TTP pre: 13.1 ± 4.3 s, TTP post: 13.6 ± 4.2 s , P = 0.058). The changes in the aforementioned parameters were not accompanied by significant tumor shrinkage. CONCLUSION: pCEUS, even when limited to the study of the arterial phase of tumoral enhancement, can detect and quantify early perfusional changes in HCC post TACE.
文摘In patients with colorectal liver metastasis(CRLMs)unsuitable for surgery,oncological treatments,such as chemotherapy and targeted agents,can be performed.Cross-sectional imaging[computed tomography(CT),magnetic resonance imaging(MRI),18-fluorodexoyglucose positron emission tomography with CT/MRI]evaluates the response of CRLMs to therapy,using post-treatment lesion shrinkage as a qualitative imaging parameter.This point is critical because the risk of toxicity induced by oncological treatments is not always balanced by an effective response to them.Consequently,there is a pressing need to define biomarkers that can predict treatment responses and estimate the likelihood of drug resistance in individual patients.Advanced quantitative imaging(diffusionweighted imaging,perfusion imaging,molecular imaging)allows the in vivo evaluation of specific biological tissue features described as quantitative parameters.Furthermore,radiomics can represent large amounts of numerical and statistical information buried inside cross-sectional images as quantitative parameters.As a result,parametric analysis(PA)translates the numerical data contained in the voxels of each image into quantitative parameters representative of peculiar neoplastic features such as perfusion,structural heterogeneity,cellularity,oxygenation,and glucose consumption.PA could be a potentially useful imaging marker for predicting CRLMs treatment response.This review describes the role of PA applied to cross-sectional imaging in predicting the response to oncological therapies in patients with CRLMs.
基金supported partly by the National Natural Science Foundation of China(Nos.61775142 and 61705132)the Shenzhen Basic Research Project on the subject layout(No.JCYJ20170412105812811)+1 种基金the Shenzhen Basic Research Projects(Nos.JCYJ20170412105812811,JCYJ20190808164007485,and JCYJ20190808115601653)the Natural Sciences and Engineering Research Council of Canada(Nos.RGPIN-2017-05959 and RGPAS-507845-2017)
文摘We report a framing imaging based on noncollinear optical parametric amplification(NCOPA),named FINCOPA,which applies NCOPA for the first time to single-shot ultrafast optical imaging.In an experiment targeting a laser-induced air plasma grating,FINCOPA achieved 50 fs-resolved optical imaging with a spatial resolution of^83 lp∕mm and an effective frame rate of 10 trillion frames per second(Tfps).It has also successfully visualized an ultrafast rotating optical field with an effective frame rate of 15 Tfps.FINCOPA has simultaneously a femtosecond-level temporal resolution and frame interval and a micrometer-level spatial resolution.Combining outstanding spatial and temporal resolutions with an ultrahigh frame rate,FINCOPA will contribute to high-spatiotemporal resolution observations of ultrafast transient events,such as atomic or molecular dynamics in photonic materials,plasma physics,and laser inertial-confinement fusion.
基金partially supported by the National Natural Science Foundation of China(Nos.92050203,62075138,12174264,61827815,12004261,and 61775142)Natural Science Foundation of Guangdong Province(Nos.2021A1515011909 and 2022A1515011457)+1 种基金Shenzhen Fundamental Research Program(Nos.JCYJ20200109105606426,JCYJ20190808164007485,JCYJ20210324095213037,JCYJ20190808121817100,JCYJ20190808143419622,and JCYJ20190808115601653)Shenzhen Key Technology Projects(Nos.JSGG20191231144201722 and JSGG20211108092800001).
文摘Applying an ultrafast vortex laser as the pump,optical parametric amplification can be used for spiral phase-contrast imaging with high gain,wide spatial bandwidth,and high imaging contrast.Our experiments show that this design has realized the 1064 nm spiral phase-contrast idler imaging of biological tissues(frog egg cells and onion epidermis)with a spatial resolution at several microns level and a superior imaging contrast to both the traditional bright-or dark-field imaging under a weak illumination of 7 nW/cm^(2).This work provides a powerful way for biological tissue imaging in the second near-infrared region.
基金supported by the State Key Program for Basic Research of China(No.2010CB630706)the Knowledge Innovation Program of Chinese Academy of Sciences
文摘A weak infrared （IR） image amplifier with more than 60-dB optical gain and is developed from a picosecond （PS） 355-nm pumped gated optical parametric frequency up-conversion amplifier （OPA） in a/% BaB204 （BBO） crystal. The IR image at 1064 nm is amplified and up-converted into the visible region at 532 nm by parametric amplification and up-conversion. With the optimized optical gain, the lowest detectable energy of the image can be as low as 1.8 femto-Joule per pulse, which is three orders of magnitude lower than the detection limit of a charge-coupled device （CCD） camera. The transversal resolution of the OPA imaging is investigated, and the approaches for higher detection sensitivity and higher transversal resolution are proposed.
