The role of whole-body FDG [(~(18)F)2-fluoro-2-deoxy-glucose] positron emission tomography(PET)scan-ning as an imaging modality in the management of patients with malignancy has evolved enormously over the past two d...The role of whole-body FDG [(~(18)F)2-fluoro-2-deoxy-glucose] positron emission tomography(PET)scan-ning as an imaging modality in the management of patients with malignancy has evolved enormously over the past two decades.FDG-PET has demonstrated signifi cant effi cacy in the staging,prognostication and detection of occult metastatic disease in malignancies of the gastrointestinal tract,in addition to assessment of the response to cytotoxic chemotherapy in a more timely manner than has traditionally been possible by more conventional imaging tools.The sensitivity and specif icity of FDG-PET for the detection and staging of malignancy depend not only on the site and size of the primary tumor and metastases,but also on histologi-cal cell type,reflecting underlying disparities in glucose metabolism.The metabolic response to neo-adjuvant chemotherapy or to chemo-radiotherapy in cancers of the gastro-esophageal junction or stomach has been demonstrated in several prospective studies to correlate signifi cantly with both the histological tumor response to treatment and with consequent improvements in overall survival.This may offer a future paradigm ofpersonalized treatment based on the PET response to chemotherapy.FDG-PET has been less successful in efforts to screen for and detect recurrent upper gastro-intestinal malignancies,and in the detection of low vol-ume metastatic peritoneal disease.Efforts to improve the accuracy of PET include the use of novel radiotrac-ers such as(~(18)F)FLT(3-deoxy-3-fluorothymidine)or 11C-choline,or fusion PET-CT with concurrent high-res-olution computed tomography.This review focuses on the role of FDG-PET scanning in staging and response assessment in malignancies of the upper gastrointesti-nal tract,specif ically gastric,esophageal and pancreas carcinoma.展开更多
Objective To investigate the relationship between tinnitus and glucose metabolism in auditory cortex and whether positron emission tomography (PET) can be an objective tool in measuring tinnitus.Methods Eleven right...Objective To investigate the relationship between tinnitus and glucose metabolism in auditory cortex and whether positron emission tomography (PET) can be an objective tool in measuring tinnitus.Methods Eleven right-handed patients with severe tinnitus and ten right-handed control subjects participated in the 18 F-FDG/PET study. Analysis with regions of interests was used to calculate asymmetry indices according to the formula: [(L-R)×100/[(L+R)÷2]].Results Glucose metabolism in the auditory cortex of tinnitus patients was asymmetric between the left and right auditory cortices, with that of the left being much higher than that of the right. The asymmetry indices of tinnitus patients was significantly higher than that of the control group (unpaired t test, P<0.001). This revealed that the increased metabolic activity was present in the predominant left hemisphere with a significant focus on the superior and transverse temporal gyri (Brodmann areas 41 and 42, respectively corresponding to primary and secondary auditory cortex), and the results were independent of the subjective localization of the tinnitus sensation.Conclusion It is suggested that the increased metabolism in the left auditory cortex is related to the tinnitus sensation. PET is capable of providing objective evidence for tinnitus and may be used as a potential tool in measuring tinnitus.展开更多
文摘The role of whole-body FDG [(~(18)F)2-fluoro-2-deoxy-glucose] positron emission tomography(PET)scan-ning as an imaging modality in the management of patients with malignancy has evolved enormously over the past two decades.FDG-PET has demonstrated signifi cant effi cacy in the staging,prognostication and detection of occult metastatic disease in malignancies of the gastrointestinal tract,in addition to assessment of the response to cytotoxic chemotherapy in a more timely manner than has traditionally been possible by more conventional imaging tools.The sensitivity and specif icity of FDG-PET for the detection and staging of malignancy depend not only on the site and size of the primary tumor and metastases,but also on histologi-cal cell type,reflecting underlying disparities in glucose metabolism.The metabolic response to neo-adjuvant chemotherapy or to chemo-radiotherapy in cancers of the gastro-esophageal junction or stomach has been demonstrated in several prospective studies to correlate signifi cantly with both the histological tumor response to treatment and with consequent improvements in overall survival.This may offer a future paradigm ofpersonalized treatment based on the PET response to chemotherapy.FDG-PET has been less successful in efforts to screen for and detect recurrent upper gastro-intestinal malignancies,and in the detection of low vol-ume metastatic peritoneal disease.Efforts to improve the accuracy of PET include the use of novel radiotrac-ers such as(~(18)F)FLT(3-deoxy-3-fluorothymidine)or 11C-choline,or fusion PET-CT with concurrent high-res-olution computed tomography.This review focuses on the role of FDG-PET scanning in staging and response assessment in malignancies of the upper gastrointesti-nal tract,specif ically gastric,esophageal and pancreas carcinoma.
文摘Objective To investigate the relationship between tinnitus and glucose metabolism in auditory cortex and whether positron emission tomography (PET) can be an objective tool in measuring tinnitus.Methods Eleven right-handed patients with severe tinnitus and ten right-handed control subjects participated in the 18 F-FDG/PET study. Analysis with regions of interests was used to calculate asymmetry indices according to the formula: [(L-R)×100/[(L+R)÷2]].Results Glucose metabolism in the auditory cortex of tinnitus patients was asymmetric between the left and right auditory cortices, with that of the left being much higher than that of the right. The asymmetry indices of tinnitus patients was significantly higher than that of the control group (unpaired t test, P<0.001). This revealed that the increased metabolic activity was present in the predominant left hemisphere with a significant focus on the superior and transverse temporal gyri (Brodmann areas 41 and 42, respectively corresponding to primary and secondary auditory cortex), and the results were independent of the subjective localization of the tinnitus sensation.Conclusion It is suggested that the increased metabolism in the left auditory cortex is related to the tinnitus sensation. PET is capable of providing objective evidence for tinnitus and may be used as a potential tool in measuring tinnitus.