-
Ryusuke Murakami, Shinichiro Kumita,
Hitomi Tani,
Tamiko Yoshida,
Kenichi Sugizaki,
Tomoyuki Kuwako,
Tomonari Kiriyama,
Kenta Hakozaki,
Emi Okazaki,
Keiko Yanagihara,
Shinya Iida,
Shunsuke Haga,
Shinichi Tsuchiya
[show abstract]
[hide abstract]
ABSTRACT: A study was conducted to evaluate the sensitivity of computer-aided detection (CAD) with full-field digital mammography in detection of breast cancer, based on mammographic appearance and histopathology. Retrospectively, CAD sensitivity was assessed in total group of 152 cases for subgroups based on breast density, mammographic presentation, lesion size, and results of histopathological examination. The overall sensitivity of CAD was 91 % (139 of 152 cases). CAD detected 100 % (47/47) of cancers manifested as microcalcifications; 98 % (62/63) of those manifested as non-calcified masses; 100 % (15/15) of those manifested as mixed masses and microcalcifications; 75 % (12/16) of those manifested as architectural distortions, and 69 % (18/26) of those manifested as focal asymmetry. CAD sensitivity was 83 % (10/12) for cancers measuring 1-10 mm, 92 % (37/40) for those measuring 11-20 mm, and 92 % (92/100) for those measuring >20 mm. There was no significant difference in CAD detection efficiency between cancers in dense breasts (88 %; 69/78) and those in non-dense breasts (95 %; 70/74). CAD showed a high sensitivity of 91 % (139/152) for the mammographic appearance of cancer and 100 % sensitivity for identifying cancers manifested as microcalcifications. Sensitivity was not influenced by breast density or lesion size. CAD should be effective for helping radiologists detect breast cancer at an earlier stage.
Journal of Digital Imaging 01/2013; · 1.25 Impact Factor
-
Journal of Nippon Medical School 01/2013; 80(1):2-3.
-
[show abstract]
[hide abstract]
ABSTRACT: Background
Two-dimensional (2D) Look-Locker MRI technique can identify myocardial fibrosis, but cannot cover the whole left ventricle during a single scan.PurposeTo develop breath-hold three-dimensional (3D) Look-Locker MRI for the evaluation of postcontrast myocardial and blood T1 values and myocardial scarring in the left ventricle.Material and MethodsA phantom and 24 patients with myocardial diseases underwent gadolinium-enhanced 2D and 3D Look-Locker MRI using a 1.5-T unit. We compared the T1 value of the phantom and the values of the myocardium and blood in the patients between the two Look-Locker MRI sequences. In the patient study, the scan ordering of the two Look-Locker MRI was selected randomly. We also assessed the ability of the 3D imaging to detect myocardial scarring that was confirmed by late gadolinium enhancement MRI.ResultsThe phantom study showed a good agreement for the T1 value between 2D and 3D Look-Locker MRI. There were no significant differences in the myocardial T1 values after contrast between 2D and 3D Look-Locker MRI or in the T1 values between the two imaging slices on the 3D Look-Locker MRI (P > 0.10). A better agreement for the myocardial T1 values was found when the 3D Look-Locker imaging was performed first. The T1 values for blood were affected by the scan order (P < 0.05). The 3D Look-Locker MRI showed myocardial scarring with a shorter T1 value (290.4 ± 62.7 ms) than those for unscarred myocardium (360.8 ± 30.3 ms).Conclusion
Three-dimensional Look-Locker MRI may precisely estimate the postcontrast myocardial and blood T1 values for the entire left ventricle during a single scan.
Acta Radiologica 11/2012; · 1.37 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We assessed the function of sympathetic nerves distributed to skeletal muscles by measuring the uptake of iodine 123 metaiodobenzylguanidine (MIBG), and examined the relationship to pressor responses during exercise. A total of 24 patients with heart disease performed treadmill exercise, and whole body delayed MIBG imaging was carried out. Based on the leg to brain ratio of MIBG (L/B), subjects were classified into two groups consisting of 10 with low L/B and 14 with preserved L/B. Results: 1) The peak systolic blood pressure (BP) during exercise was higher in the group with low L/B than in the group with preserved L/B. 2) There were no differences in plasma noradrenaline levels between the two groups. Conclusion: These results suggest that denervation supersensitivity may influence the BP response to exercise in patients with heart disease.
Journal of The Japanese Coronary Association. 11/2012; 18(3):189-193.
-
[show abstract]
[hide abstract]
ABSTRACT: PURPOSE: To evaluate the usefulness of magnetic resonance imaging (MRI) for detection and quantification of myocardial damage related to clinical phases and cardiac function during eosinophilic myocarditis. MATERIALS AND METHODS: Four eosinophilic myocarditis patients received seven MRI studies. The left ventricular myocardium was divided into 48 layers, and we quantified the extent of abnormal intensity detected by T2-weighted or delayed enhancement MRI relative to the clinical phase and global cardiac function. RESULTS: T2-weighted imaging detected extensive myocardial hyperintensity during the acute phase of eosinophilic myocarditis. Diffuse myocardial delayed enhancement was observed in one patient during the acute phase, but not in the other. Little or no hyperintensity was detected by T2-weighted imaging or myocardial delayed enhancement during the convalescent phase. The extent of hyperenhancing myocardial layers was inversely correlated with the ejection fraction (EF) (r = -0.87). CONCLUSION: MRI can evaluate the presence and extent of myocardial damage related to the clinical phases and EF during eosinophilic myocarditis.
Japanese journal of radiology 09/2012; · 0.65 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: A review of patients with skull base osteosarcoma secondary to radiation (radiation-induced osteosarcoma: RIOS) of the pituitary tumor shows the mean survival of approximately 7 months (2 weeks - 16 months). This warning prognosis seems to stem from two factors, 1) the anatomical complexity of the skull base for total resection of the tumor, and 2) standard adjuvant therapies for the tumor yet to be established. Contrary to the general belief, the authors report an unusually long survival of a 75-year-old woman with a history of osteosarcoma that developed in the same sequence 20 years after pituitary tumor radiation. On her recent admission, she complained of frontal headaches and MRI studies showed a tumor in the sphenoid sinus. Endoscopic trans-nasal tumor removal allowed for histological diagnosis of an osteosarcoma. However, further rapid tumor growth necessitated a radical tumor resection followed by a combined chemotherapy with ifosfamide, cisplatin, and etoposide (ICE). Despite temporary suppression of the tumor growth, the chemotherapy was discontinued due to severe pancytopenia that occurred after three courses of treatment. Shortly after the discontinuation of ICE therapy, the tumor size increased again rapidly, requiring a novel radiation therapy, Cyber-knife treatment. Following this radiation, the tumor growth was arrested, and the patient remains healthy without neurological symptoms over 24 months. The outcome of Cyber-knife in this case suggests that this specific therapy must be considered for the unresectable skull base RIOS.
Radiation Oncology 08/2012; 7(1):136. · 2.32 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Gastric schwannoma is a rare tumor that accounts for only 0.2 % of all gastric tumors. We report a case of gastric schwannoma that underwent computed tomography (CT), magnetic resonance imaging (MRI), and [(18)F]-fluorodeoxyglucose positron emission tomography (FDG-PET), and its histological confirmation was acquired. Gastric schwannoma showed high intensity on T2-weighted and diffusion-weighted MRI and high maximum standardized uptake on [(18)F]-FDG-PET. Lymphadenopathy close to the tumor was also found. Although diffusion-weighted MRI, [(18)F]-FDG-PET, and the presence of lymphadenopathy could suggest malignant tumors, the detail interpretation of the other CT and MRI findings may give a clue for the diagnosis of gastric schwannoma.
Japanese journal of radiology 06/2012; 30(7):602-5. · 0.65 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Asymmetric septal hypertrophic cardiomyopathy (ASH) is the common phenotype of hypertrophic cardiomyopathy (HCM). We sought to classify ASH using magnetic resonance imaging (MRI) and to determine whether the MRI classification of ASH is related to the presence of risk factors for HCM. Ninety-three patients with ASH underwent cine and delayed-enhancement MRI. The ASH was classified morphologically using cine MRI at end-diastole. We evaluated the association between the MRI findings and the presence of risk factors in the ASH. The ASH was classified into three subtypes by MRI: contiguous subtype showing various clinical and MRI features (57%), sigmoid subtype (29%) with fewer risk factors, and reverse-curve subtype (14%) in younger patients with the larger myocardial mass and delayed-enhancement, which were significantly related to the risk factors. MRI was used to classify ASH into three subtypes, which might be related to the presence of risk factors.
The international journal of cardiovascular imaging 03/2012; · 2.15 Impact Factor
-
Journal of Cardiovascular Magnetic Resonance 02/2012; 14 Suppl 1:W40. · 3.72 Impact Factor
-
Journal of Cardiovascular Magnetic Resonance 02/2012; 14 Suppl 1:P152. · 3.72 Impact Factor
-
Journal of Cardiovascular Magnetic Resonance 02/2012; 14 Suppl 1:P302. · 3.72 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To compare the antitumor efficacy and safety of transcatheter arterial chemoembolization (TACE) by epirubicin suspension (epirubicin suspension: epirubicin-iodized oil mixture without solution) to that by epirubicin emulsion (epirubicin emulsion: epirubicin-iodized oil mixture with solution), the efficacy of treatment by administration of either an epirubicin suspension or emulsion was examined in an animal model. Changes in plasma epirubicin concentration were compared over 24 h immediately after treatment, and enhanced ultrasonographic and histopathological analysis subsequently conducted 7 days after treatment to determine the growth ratio and proportion of viable tumor cells. The growth ratio and proportion of viable tumor cells were found to be significantly lower in the suspension group than in the emulsion group while the plasma epirubicin concentration was found to be significantly higher in the suspension group than in the emulsion group. These results indicate that administration of an epirubicin suspension is a superior form of TACE compared to that of administration of an epirubicin emulsion.
TheScientificWorldJOURNAL 01/2012; 2012:961986. · 1.66 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The purpose of this paper is to describe imaging techniques and findings of T2-weighted magnetic resonance imaging (MRI) of edema in myocardial diseases. T2-weighted cardiac MRI is acquired by combining acceleration techniques with motion and signal suppression techniques. The MRI findings should be interpreted based on coronary artery supply, intramural distribution, and comparison with delayed-enhancement MRI. In acute myocardial diseases, such as acute myocardial infarction and myocarditis, the edema is larger than myocardial scarring, whereas the edema can be smaller than the scarring in some types of nonischemic cardiomyopathy, including hypertrophic cardiomyopathy. T2-weighted MRI of edema identifies myocardial edema associated with ischemia, inflammation, vasculitis, or intervention in the myocardium and provides information complementary to delayed-enhancement MRI.
TheScientificWorldJOURNAL 01/2012; 2012:194069. · 1.66 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Sarcoidosis is a multisystem disorder of unknown etiology that involves multiple organs. Computed tomography is the first-line imaging modality for diagnosing sarcoidosis because of its capacity to detect hilar lymphadenopathy and pulmonary lesions. Magnetic resonance (MR) imaging provides good soft tissue contrast that is useful for detecting sarcoidosis in some body parts, including skeletal muscle. Signal intensity on pre- and postcontrast T(1)- and T(2)-weighted imaging may reflect disease activity and the pathological appearance of sarcoidosis. In this review, we demonstrate these conventional MR imaging findings of hepatosplenic and muscular sarcoidosis and describe the usefulness of diffusion-weighted imaging for detecting sarcoidosis.
Magnetic Resonance in Medical Sciences 01/2012; 11(2):83-9. · 0.97 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To study tissue platinum concentrations and the correlation between tissue and plasma platinum concentrations after negative-balance isolated pelvic perfusion (NIPP) in a porcine model.
All animal experiments were conducted according to the University Guidelines for Animal Care and Experimentation. Cisplatin (5 mg per kilogram of body weight) was administered into balloon catheter-isolated porcine pelvic circulations (n=7) and also systemically to a control group (n=7). Platinum concentrations in pelvic blood, systemic blood, urine, pelvic tissues (uterus, bladder, lymph nodes, and muscles), and kidneys were measured. Maximum platinum concentration (maximum serum drug concentration [C-max]) and area under the blood concentration-time curve (AUC) were compared between the two groups.
With NIPP, pelvic C-max (58.4 mg/L) and AUC (1163.6 mg⋅min/L) were 44.9- and 56.2-fold higher than systemic C-max (1.3 mg/L) and AUC (20.7 mg⋅min/L), respectively, whereas the corresponding values in the control group were almost identical. Tissue platinum concentrations in pelvic organs were 2.8-5.6-fold higher than the control values. Platinum concentrations in kidney tissue were markedly lower with NIPP (1.0 mg/L) compared with the controls (8.1 mg/L). High platinum concentrations in pelvic tissues correlated well (P<.01) with high pelvic C-max and AUC.
The pharmacologic advantages of NIPP were evident, with achievement of high platinum C-max, AUC, and high pelvic tissue concentrations without exposing systemic organs to platinum.
Radiology 12/2011; 262(2):503-10. · 5.73 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Aim: To evaluate the antitumor effects and hepatotoxicity of transcatheter arterial chemoembolization (TACE) with cisplatin-iodized oil suspension and emulsion in a rabbit tumor model. Methods: Transcatheter arterial chemoembolization was performed on 12 rabbits with hepatic VX2 tumors using a cisplatin suspension (1 mg/kg cisplatin and 0.1 mL/kg iodized oil, n = 6) or emulsion (1 mg/kg cisplatin, 0.1 mL/kg of iodized oil, and 0.1 mL/kg saline solution, n = 6). Time series changes in plasma platinum concentration were compared over 24 h. All rabbits were killed at 7 days after TACE, and the growth ratio and residual viable proportion of tumors were calculated on the basis of ultrasonographic and histopathological findings. Hepatotoxicity was also evaluated. Differences between the two groups were statistically assessed with the Mann-Whitney U-test. The animal care committee of our institute approved this study. Results: Plasma platinum concentrations were significantly higher in the suspension group than in the emulsion group at 0.5-24 h after TACE (P < 0.05). Growth ratios (-24.6 ± 9.98% vs. 21.4 ± 8.87%, respectively; P = 0.004) and residual viable proportions of tumors (25.8 ± 5.02% vs. 51.1 ± 11.4%, respectively; P = 0.009) were significantly lower in the suspension group than in the emulsion group. Hepatotoxicity was transient in all rabbits. Conclusion: Cisplatin-iodized oil suspensions facilitated the slow release of cisplatin at the tumor border. A suspension is preferable to an emulsion for drug delivery and the antitumor effect during the treatment of VX2 liver tumors with TACE.
Hepatology Research 12/2011; 42(5):473-81. · 2.20 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate the clinical feasibility of embolization with n-butyl cyanoacrylate (NBCA) for endoscopically unmanageable non-variceal gastrointestinal hemorrhage (GIH).
Between June 2004 and May 2009, 61 patients with confirmed acute upper and/or lower GIH underwent emergency embolization for haemorrhage control; NBCA was used in 28 of these patients, all of whom were in shock despite receiving blood transfusions. The results were studied retrospectively. Clinical parameters and embolization data were assessed for technical success, clinical success and outcome.
Technical success was achieved in all patients. Clinical success was achieved in 19 (68%) of the 28 patients. The mortality rate was 25% (7 patients). The cause of death was disseminated intravascular coagulation (DIC) in 6 patients and heart failure in 1. The presence of coagulopathy or DIC significantly decreased the degree of clinical success (p=0.015, p=0.001, respectively) and increased the mortality rate (p=0.013, p<0.001, respectively). Unfortunately, 86% patients who had DIC before embolization, died. Conclusions: NBCA embolization is technically feasible and is effective for the control of haemorrhage in endoscopically unmanageable GIH. However, the presence of coagulopathy or DIC significantly decreases the clinical success and increases the mortality rate.
Hepato-gastroenterology 11/2011; 59(116):1126-30. · 0.66 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The aim of this study was to determine whether non-contrast-enhanced magnetic resonance imaging (MRI) can detect three levels of renal impairment by evaluating the differences and agreement with (99m)Tc-diethylenetriamine pentaacetic acid (DTPA) renography.
A total of 28 patients with kidney disease were enrolled in the study. MRI findings, including visual corticomedullary differentiation (CMD) on T1- and T2-weighted imaging (T1WI, T2WI), cortical irregularity, the number of renal cysts, and the volume of the kidney, were evaluated for individual kidneys and pairs of kidneys. The differences and agreement between MRI findings and the three levels of renal impairment based on the glomerular filtration rate (GFR) measured using (99m)Tc-DTPA renography were analyzed.
All MRI findings except the number of renal cysts in pairs of kidneys were consistent with the patient's classification. The agreement between the patient's classifications based on GFR and that based on the visual CMD on T1WI and T2WI was almost perfect or substantial in both individual kidneys and pairs of kidneys.
Non-contrast-enhanced MRI was capable of distinguishing three levels of renal function, including serious renal impairment.
Japanese journal of radiology 07/2011; 29(6):378-85. · 0.65 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: A study was conducted to evaluate the early results of high-dose-rate superficial brachytherapy (HDR-SB) after keloidectomy. Between April 2008 and April 2009, 21 patients with 36 histologically confirmed keloids were treated with postoperative HDR-SB. The tube applicator was placed on the skin to match the area of the surgical wound, and a spacer 5 mm thick was placed between the skin and the applicator. A dose evaluation point was established below 2 mm from skin surface, and 20 Gy was delivered in 4 daily fractions to keloidectomy scars on the anterior chest wall, scapular region, lower jaw and suprapubic region. A dose of 15 Gy was delivered in 3 daily fractions to lesions in other areas. The median follow-up period was 18 months (range, 9 to 29 months). Therapeutic outcome was judged in terms of recurrence, control, or acute side effects. Three keloids (9.7%) in two patients showed local recurrence, with a median time to failure after HDR-SB of 12 months. All recurrences affected the anterior chest wall. Dysraphia occurred in only one patient with an anterior chest wall lesion. Excluding the cases of recurrence, acceptable cosmetic results were achieved. Our results indicate that HDR-SB is effective and safe for preventing recurrence of keloids.
Journal of Radiation Research 05/2011; 52(3):365-8. · 1.68 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Hypertrophic cardiomyopathy (HCM) is reported to show patchy midwall myocardial hyperenhancement on delayed-enhancement magnetic resonance imaging (DE-MRI). The intramural distribution of myocardial hyperenhancement and its correlation with clinical symptoms, ventricular arrhythmias, and cardiac function have not been described forsymptomatic apical HCM.
To evaluate the features and significance of myocardial hyperenhancement on DE-MRI insymptomatic apical HCM.
Thirteen patients with symptomatic apical HCM and their 65 apical segments were investigated. Myocardial hyperenhancement and regional and global functional parameters were determined with MRI. We investigated the intramural distribution and frequencies of this myocardial hyperenhancement and compared them with the patients' clinical symptoms, the presence of ventricular arrhythmias, and cine MRI.
Eight (61.5%) patients with symptomatic apical HCM displayed apical myocardial hyperenhancement, and 22 (33.8%) of the 65 apical segments examined showed myocardial hyperenhancement. Of the myocardial hyperenhancement observed, 81.8% showed a subendocardial pattern.The hyperenhanced apical myocardium had a lower percentage of systolic myocardial thickening, and was associated with serious symptoms (e.g. syncope) and ventricular arrhythmias.
Patients with symptomatic apical HCMshowed myocardial hyperenhancement involving the subendocardial layer, which might be related to regional systolic dysfunction, serious clinical symptoms, and ventricular arrhythmias.
Acta Radiologica 04/2011; 52(6):613-8. · 1.37 Impact Factor
