キョウマク シッカン ノ ガゾウ シンダン

Diagnostic imaging plays an essential role in the evaluation of asbestos-related disease, especially malignant pleural mesothelioma（MPM）. MPM is forecast to peak at 20000 deaths per 5 years between 2030 and 2040 in Japan. Till now, high resolution CT and MRI are widely used for diagnosis and staging of MPM. Key CT findings of MPM include unilateral pleural effusion, nodular pleural thickening and interlobular fissural thickening. The recent use of integrated FDG-PET/CT imaging with coregistration of anatomic and functional imaging data may improve the differentiation between malignant and benign lesions , the accuracy of staging of MPM, and the evaluation of therapeutic response

Accurate estimation of regional and global cardiac function in old myocardial infarction patients by multidetector-row computed tomography

Recently we can evaluate cardiac function by multidetector-row computed tomography (MDCT) and quantitative gated SPECT (QGS) as well as left ventriculography (LVG). We evaluated regional and global cardiac function using MDCT and QGS, compared to LVG, and also evaluated parameters of left ventricular (LV) diastolic function using MDCT. Regional cardiac function was evaluated using shortening fraction (SF). Global cardiac function was evaluated using ejection fraction(EF). The peak filling rate (PFR) and the ratio of time to peak filling rate to RR interval (tPFR/RR) on MDCT were measured as parameters of LV diastolic function. The SFs by MDCT and LVG were correlated in almost each segment, but those by QGS and LVG were not correlated in some each segment. The SFs by QGS and LVG were not correlated in the myocardial infarcted segments, but those by QGS and LVG were correlated in the non-infarcted segments. Except for patients who had wall motion abnormalities at the ventricular septum or posterolateral wall, the EFs by MDCT and LVG were correlated, but those by QGS and LVG were not correlated. MDCT was more useful in detecting regional and global cardiac function compared to QGS, and parameters of LV diastolic function could be also measured by MDCT

Embolic infarction followed by serial bone SPECT and MR fusion images : the door to SPECT/MR

We recently experienced a case of cerebral infarction incidentally found by whole body bone scintigraphy for the detection of bone metastasis from renal cell carcinoma. Additional bone SPECT and brain MR fusion images clearly demonstrated the wedge-shaped uptake of tracer corresponded to the abnormal intensity reflecting subacute cerebral infarction. Follow-up bone scan and fused images with MRI showed complete resolution of the abnormal uptake in chronic phase. A breakdown in the normal blood-brain barrier results in abnormal ionic calcium flux into the cells following altered cell membrane integrity leading to precipitation of calcium salts which eventually binds to bone imaging tracer such as 99mTc-methylene diphosphonate. That is, increased accumulation of bone seeking agents represents lethal cell death. The recent development of software and hardware has enabled the fusion of functional and anatomic images. Image fusion between SPECT with various tracers and MRI is expected to provide clues as to the underlying cause of diseases and to decide our treatment planning in the near future

Three-dimensional imaging of thoracic diseases with multidetector row CT

The benefits of multi-detector row CT (MDCT) relative to single-detector row helical CT are considerable. Multi-detector row CT allows shorter acquisition times, greater coverage, and superior image resolution. These factors substantially increase the diagnostic accuracy of the examination. Three-dimensional (3D) volume data from MDCT provides various unique applications on thoracic diseases. These includes isotropic viewings, use of multi planar reformation (MPR), maximum and minimum intensity projections (MIP and min IP), and volume rendering performed from external and internal perspectives allowing the user to “fly around” and “fly through” the structures. Recent advances in 3D volume rendering put real-time, interactive virtual reality guidance of the procedures such as bronchoscopy and surgery into practice

Risk factors associated with soft coronary artery plaques in Japanese, as determined by 16 slice multidetector-row computed tomography

Purpose: The acute coronary syndrome is often caused by the rupture of plaques and thrombus formation even without significant stenosis, and patients with soft plaques, but without significant stenosis evidenced by coronary angiography(CAG), often develop an acute coronary syndrome. To address this discrepancy, a qualitative diagnosis of coronary plaques using a 16 slice multidetector-row CT was conducted. Methods and Results: Volume rendering and cross-sectional MPR images were obtained. Based on the CT values, plaques on the coronary artery wall were classified as lipid-rich soft plaques(CT value50 HU) . A significant correlation was observed between the percent stenosis determined in crosssectional MPR images and those determined by CAG(r=＋0.92, p<0.01). Diffuse plaques with CT values of less than 50 HU often caused stenosis at level of 75% or less, which were not indicated by percutaneous transluminal coronary angioplasty. Conclusions : Although diffuse soft plaques with CT values less than 50 HU are not an indication of intervention, a risk of an acute coronary syndrome exists, due to rupture. These soft plaques must be stabilized by treatment even when they do not cause significant stenosis, and MDCT is considered to be useful for their evaluation

Two cases of retroperitoneal hematoma caused by combination of anticoagulant therapy and 5-fluorouracil

We reported two cases of retroperitoneal hematoma in patients who received a combination of anticoagulant therapy and5-fluorouracil (5-FU). We should be aware of the possible interaction of this combination therapy and monitor prothrombin time (PT) prolongation. CT is useful for evaluation of the disease

Diagnostic Value of ¹⁸F-FDG PET/MRI for Revised 2018 FIGO Staging in Patients with Cervical Cancer

Purpose: To evaluate the diagnostic potential of PET/MRI with 18F-fluorodeoxyglucose (18F-FDG) in cervical cancer based on the revised 2018 International Federation of Gynecology and Obstetrics (FIGO) staging system. Materials and Methods: Seventy-two patients with biopsy-proven primary cervical cancer underwent pretreatment 18F-FDG PET/MRI, CT, and pelvic MRI. The diagnostic performance of 18F-FDG PET/MRI and MRI for assessing extent of the primary tumor and 18F-FDG PET/MRI and CT for assessing nodal and distant metastases was evaluated by two experienced readers. Histopathological and follow-up imaging results were used as the gold standard. McNemar test was employed for statistical analysis. Results: Accuracy for the invasion of vagina, parametrium, side wall, and adjacent organs was 97.2%, 93.1%, 97.2%, and 100% for 18F-FDG PET/MRI; and 97.2%, 91.7%, 97.2%, and 100% for pelvic MRI, respectively (p > 0.05). Patient-based accuracy for metastasis to pelvic and paraaortic lymph nodes and distant organs was 95.8%, 98.6%, and 100% for 18F-FDG PET/MRI; and 83.3%, 95.8%, and 97.2% for CT, respectively; metastasis to pelvic lymph nodes was statistically significant (p 18F-FDG PET/MRI; and 29.2%, 98.9% and 93.1% for CT, respectively; sensitivity was statistically significant (p 18F-FDG PET/MRI (82.1%) than for CT and MRI (60.7%) (p 18F-FDG PET/MRI offers higher diagnostic value for revised 2018 FIGO staging, suggesting that 18F-FDG PET/MRI might provide an optimal diagnostic strategy for preoperative staging