1.Virtual Monochromatic Image Quality from Dual-Layer Dual-Energy Computed Tomography for Detecting Brain Tumors
Shota TANOUE ; Takeshi NAKAURA ; Yasunori NAGAYAMA ; Hiroyuki UETANI ; Osamu IKEDA ; Yasuyuki YAMASHITA
Korean Journal of Radiology 2021;22(6):951-958
Objective:
To evaluate the usefulness of virtual monochromatic images (VMIs) obtained using dual-layer dual-energy CT (DL-DECT) for evaluating brain tumors.
Materials and Methods:
This retrospective study included 32 patients with brain tumors who had undergone non-contrast head CT using DL-DECT. Among them, 15 had glioblastoma (GBM), 7 had malignant lymphoma, 5 had high-grade glioma other than GBM, 3 had low-grade glioma, and 2 had metastatic tumors. Conventional polychromatic images and VMIs (40–200 keV at 10 keV intervals) were generated. We compared CT attenuation, image noise, contrast, and contrast-to-noise ratio (CNR) between tumor and white matter (WM) or grey matter (GM) between VMIs showing the highest CNR (optimized VMI) and conventional CT images using the paired t test. Two radiologists subjectively assessed the contrast, margin, noise, artifact, and diagnostic confidence of optimized VMIs and conventional images on a 4-point scale.
Results:
The image noise of VMIs at all energy levels tested was significantly lower than that of conventional CT images (p < 0.05). The 40-keV VMIs yielded the best CNR. Furthermore, both contrast and CNR between the tumor and WM were significantly higher in the 40 keV images than in the conventional CT images (p < 0.001); however, the contrast and CNR between tumor and GM were not significantly different (p = 0.47 and p = 0.31, respectively). The subjective scores assigned to contrast, margin, and diagnostic confidence were significantly higher for 40 keV images than for conventional CT images (p < 0.01).
Conclusion
In head CT for patients with brain tumors, compared with conventional CT images, 40 keV VMIs from DL-DECT yielded superior tumor contrast and diagnostic confidence, especially for brain tumors located in the WM.
2.Evaluation of Immune Function of Healthy Volunteer Treated with Oral Lentinula Edodes Mycelia Extract
Takashi KAWANISHI ; Yasunori MATSUI ; Ariaki NAGAYAMA
Japanese Journal of Complementary and Alternative Medicine 2018;15(1):15-19
Lentinula edodes mycelia extract has been reported to maintain and improve immune function and QOL in cancer patients. In this study, the effects of Lentinula edodes mycelia extract on immune function were investigated in 10 healthy volunteers. Ten subjects were administrated Lentinula edodes mycelia extract orally for 20 weeks on average (846 mg / day ), and the immunological function (IFNγ production amount, IL-10 production amount, lymphocyte subset)was evaluated before and after ingestion at Fukuoka Tenjin Southern Clinic. Immune function following ingestion of Lentinula edodes mycelia extract showed a tendency of IFNγ production to increase, IL - 10 to decrease, and IFNγ / IL - 10 production ratio to be improved remarkably. No significant change was observed in lymphocyte subsets such as regulatory T cells before and after ingestion. Adverse events during the intake period were not observed. It was suggested that oral intake of Lentinula edodes mycelia extract has an action to improve the immune function of healthy adults.
3.Virtual Monochromatic Image Quality from Dual-Layer Dual-Energy Computed Tomography for Detecting Brain Tumors
Shota TANOUE ; Takeshi NAKAURA ; Yasunori NAGAYAMA ; Hiroyuki UETANI ; Osamu IKEDA ; Yasuyuki YAMASHITA
Korean Journal of Radiology 2021;22(6):951-958
Objective:
To evaluate the usefulness of virtual monochromatic images (VMIs) obtained using dual-layer dual-energy CT (DL-DECT) for evaluating brain tumors.
Materials and Methods:
This retrospective study included 32 patients with brain tumors who had undergone non-contrast head CT using DL-DECT. Among them, 15 had glioblastoma (GBM), 7 had malignant lymphoma, 5 had high-grade glioma other than GBM, 3 had low-grade glioma, and 2 had metastatic tumors. Conventional polychromatic images and VMIs (40–200 keV at 10 keV intervals) were generated. We compared CT attenuation, image noise, contrast, and contrast-to-noise ratio (CNR) between tumor and white matter (WM) or grey matter (GM) between VMIs showing the highest CNR (optimized VMI) and conventional CT images using the paired t test. Two radiologists subjectively assessed the contrast, margin, noise, artifact, and diagnostic confidence of optimized VMIs and conventional images on a 4-point scale.
Results:
The image noise of VMIs at all energy levels tested was significantly lower than that of conventional CT images (p < 0.05). The 40-keV VMIs yielded the best CNR. Furthermore, both contrast and CNR between the tumor and WM were significantly higher in the 40 keV images than in the conventional CT images (p < 0.001); however, the contrast and CNR between tumor and GM were not significantly different (p = 0.47 and p = 0.31, respectively). The subjective scores assigned to contrast, margin, and diagnostic confidence were significantly higher for 40 keV images than for conventional CT images (p < 0.01).
Conclusion
In head CT for patients with brain tumors, compared with conventional CT images, 40 keV VMIs from DL-DECT yielded superior tumor contrast and diagnostic confidence, especially for brain tumors located in the WM.