Papers - AZUMA Minako
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Metastatic Cardiac Tumor Mimicking Coronary Artery Aneurysm on Postmortem Computed Tomography. Reviewed
Shinkawa N, Yamada R, Azuma M, Shinkawa N, Yukawa N
The American journal of forensic medicine and pathology 2025.3
Language：English Publishing type：Research paper (scientific journal)
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Oguri N., Gi T., Nakamura E., Maekawa K., Furukoji E., Okawa H., Kouyama S., Horiuchi S., Sawaguchi A., Sakae T., Azuma M., Asada Y., Yamashita A.
Research and Practice in Thrombosis and Haemostasis 9 ( 2 ) 2025.2
Language：English Publishing type：Research paper (scientific journal) Publisher：Research and Practice in Thrombosis and Haemostasis
Background: Novel anticoagulants targeting coagulation factor (F)XI/activated FXI (FXIa) are currently under development. However, whether FXI is present in human deep vein thrombosis (DVT) and whether FXIa and activated FX (FXa) play different roles in venous thrombus formation and hemostasis remain unclear. Objectives: To determine the presence of FXI in DVT and the effects of direct oral FXIa and FXa inhibitors on venous thrombus formation and hemostasis in rabbits and on in vitro thrombus formation. Methods: We immunohistochemically assessed FXI localization in human-aspirated DVT (n = 15). Additionally, we compared thrombus formation induced by endothelial denudation and stenosis or stasis in the jugular vein and skin bleeding time and volume between rabbits treated with direct FXIa inhibitors (ONO-1600586) and FXa inhibitors (rivaroxaban). Ex vivo rabbit and human blood were perfused in a flow chamber under low-shear rates (70/s). Results: FXI was localized in all DVT, predominantly in fibrin-rich areas. The FXI immunopositive area in the nonorganizing area was greater than that in the organizing area. Although FXIa and FXa inhibitors comparably inhibited venous thrombus formation, FXIa inhibitors did not affect bleeding time or volume in rabbits. FXIa or FXa inhibitors mildly or strongly inhibited fibrin formation at low-shear rates, respectively. Furthermore, the FXIa inhibitor suppressed human FXIa activity, thrombin generation, and fibrin formation during perfusion. Conclusion: The pathologic findings of human DVT suggest FXI's role in human DVT. FXIa inhibitors may inhibit less fibrin formation than FXa inhibitors and may explain the minor role of FXIa in hemostasis.
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Expression of fibroblast activation protein-α in human deep vein thrombosis Reviewed
Oguri N., Gi T., Nakamura E., Furukoji E., Goto H., Maekawa K., Tsuji A.B., Nishii R., Aman M., Moriguchi-Goto S., Sakae T., Azuma M., Yamashita A.
Thrombosis Research 241 109075 2024.9
Language：English Publishing type：Research paper (scientific journal) Publisher：Thrombosis Research
Background: Fibroblast activation protein-α (FAP), a type-II transmembrane serine protease, is associated with wound healing, cancer-associated fibroblasts, and chronic fibrosing diseases. However, its expression in deep vein thrombosis (DVT) remains unclear. Therefore, this study investigated FAP expression and localization in DVT. Methods: We performed pathological analyses of the aspirated thrombi of patients with DVT (n = 14), classifying thrombotic areas in terms of fresh, cellular lysis, and organizing reaction components. The organizing reaction included endothelialization and fibroblastic reaction. We immunohistochemically examined FAP-expressed areas and cells, and finally analyzed FAP expression in cultured dermal fibroblasts. Results: All the aspirated thrombi showed a heterogeneous mixture of at least two of the three thrombotic areas. Specifically, 83 % of aspirated thrombi showed fresh and organizing reaction components. Immunohistochemical expression of FAP was restricted to the organizing area. Double immunofluorescence staining showed that FAP in the thrombi was mainly expressed in vimentin-positive or α-smooth muscle actin-positive fibroblasts. Some CD163-positive macrophages expressed FAP. FAP mRNA and protein levels were higher in fibroblasts with low-proliferative activity cultured under 0.1 % fetal bovine serum (FBS) than that under 10 % FBS. Fibroblasts cultured in 10 % FBS showed a significant decrease in FAP mRNA levels following supplementation with hemin, but not with thrombin. Conclusions: The heterogeneous composition of venous thrombi suggests a multistep thrombus formation process in human DVT. Further, fibroblasts or myofibroblasts may express FAP during the organizing process. FAP expression may be higher in fibroblasts with low proliferative activity.
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Sugita C., Maekawa K., Gi T., Oguri N., Nakamura E., Furukoji E., Azuma M., Asada Y., Yamashita A.
Thrombosis Research 238 185 - 196 2024.6
Language：English Publishing type：Research paper (scientific journal) Publisher：Thrombosis Research
Background: Plaque erosion, a type of coronary atherothrombosis, involves superficial injury to smooth muscle cell (SMC)-rich plaques. Elevated levels of coagulation factor VIII (FVIII) correlate with an increased ischemic heart disease risk. FVIII may contribute to thrombus formation on eroded plaques. Aims: We aimed to elucidate the role of elevated FVIII in arterial thrombus formation within SMC-rich neointima in rabbits. Methods and results: We assessed the effect of recombinant human FVIII (rFVIII) on blood coagulation in vitro and platelet aggregation ex vivo. An SMC-rich neointima was induced through balloon injury to the unilateral femoral artery. Three weeks after the first balloon injury, superficial erosive injury and thrombus formation were initiated with a second balloon injury of the bilateral femoral arteries 45 min after the administration of rFVIII (100 IU/kg) or saline. The thrombus area and contents were histologically measured 15 min after the second balloon injury. rFVIII administration reduced the activated partial thromboplastin time and augmented botrocetin-induced, but not collagen- or adenosine 5′-diphosphate-induced, platelet aggregation. While rFVIII did not influence platelet-thrombus formation in normal intima, it increased thrombus formation on SMC-rich neointima post-superficial erosive injury. Enhanced immunopositivity for glycoprotein IIb/IIIa and fibrin was observed in rFVIII-administered SMC-rich neointima. Neutrophil count in the arterial thrombus on the SMC-rich neointima correlated positively with thrombus size in the control group, unlike the rFVIII group. Conclusions: Increased FVIII contributes to thrombus propagation within erosive SMC-rich neointima, highlighting FVIII's potential role in plaque erosion-related atherothrombosis.
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Uchimura R., Khant Z.A., Hayashi H., Nagayama Y., Uetani H., Kaku Y., Nagatomo T., Tamura Y., Yokogami K., Mukasa A., Kiyosue H., Azuma M., Hirai T.
Journal of Computer Assisted Tomography 2024
Language：English Publishing type：Research paper (scientific journal) Publisher：Journal of Computer Assisted Tomography
Objective Discriminating between hemorrhage and iodine extravasation can pose challenges in conventional computed tomography (CCT) images following preoperative embolization for meningioma. This study aimed to assess the efficacy of dual-energy computed tomography (DECT) in differentiating hemorrhage from iodine extravasation after preoperative embolization for meningioma. Methods Twenty-one consecutive meningioma patients who underwent CCT before and DECT immediately after preoperative embolization were included in this study. Two independent observers conducted qualitative assessments on CCT and virtual noncontrast (VNC) images and iodine maps (IMs) to differentiate between hemorrhage and iodine extravasation. One observer recorded CT values of hemorrhage and iodine extravasation on CCT and VNC images. The ratio of maximum attenuation to minimum attenuation on VNC images was defined as the VNC ratio. Statistical analysis included Kappa (κ) statistics, unpaired t tests, and receiver operating characteristic (ROC) analysis. Results Interobserver agreement for qualitative assessment was fair (κ = 0.231) for CCT alone and good (κ = 0.723) for CCT plus VNC imaging and IM. The addition of VNC imaging and IM to CCT improved differential confidence in 16 (76%) and 18 (86%) cases of the two observers, respectively, increasing the area under the receiver operating characteristic curve (AUROC) from 0.868 to 0.895 and 0.658 to 0.947, respectively. At a cutoff value of 1.527, the VNC ratio was significantly higher for hemorrhage than iodine extravasation (P < 0.05), with the highest diagnostic performance (AUROC, 1). Conclusions DECT with VNC imaging and IM is useful for differentiating hemorrhage from iodine extravasation in meningiomas with preoperative embolization.
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A Follow-up Study of National Survey on Safety Management at MR Imaging Facilities in Japan
AZUMA Minako, DOI Tsukasa, TAKAHASHI Mitsuyuki, HATA Hirofumi, UEYAMA Tsuyoshi, TAKAHASHI Junji, SAKAI Kazuyuki, OYAMA-MANABE Noriko, HATA Junichi, KATAOKA Masako, KURODA Kagayaki, IJICHI Shinpei, AOKI Shigeki, HIRAI Toshinori
Japanese Journal of Magnetic Resonance in Medicine 43 ( 4 ) 144 - 173 2023.11
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japanese Society for Magnetic Resonance in Medicine
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Usefulness of Voxel-Based Quantification (VBQ) Smoothing in Relaxation Time Mapping
Fukunaga Kota, Fujiwara Yasuhiro, Enzaki Masahiro, Komi Masanori, Hirai Toshinori, Azuma Minako
Japanese Journal of Radiological Technology 79 ( 9 ) 913 - 922 2023.9
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japanese Society of Radiological Technology
<i>Purpose</i>: Voxel-based quantification (VBQ) smoothing is a technique used to smooth quantitative parametric maps in the Montreal Neurological Institute standard space. Although VBQ smoothing could suppress changes in quantitative values at tissue boundaries, its effectiveness on relaxation time (T<sub>1</sub> and T<sub>2</sub> values and proton density PD) maps has not been investigated. The purpose of this study was to clarify the usefulness of VBQ smoothing in relaxation time mapping. <i>Method</i>: T<sub>1</sub> and T<sub>2</sub> values and PD maps of the brains of 20 healthy participants were obtained using a two-dimensional multi-dynamic multi-echo sequence. VBQ and Gaussian smoothing were applied to the relaxation time maps by varying the kernel size by 1 mm from 1 to 6 mm. Changes in relaxation time before and after VBQ and Gaussian smoothing for the putamen, caudate nucleus, substantia nigra, and corpus callosum on the relaxation time maps were evaluated. <i>Result</i>: The changes in relaxation time after VBQ smoothing application were smaller than those in that after Gaussian smoothing application. Although the differences in the relaxation time for all tissues before and after VBQ and Gaussian smoothing applications increased with increasing kernel size for all relaxation times for both methods, the changes in the relaxation time for VBQ smoothing were smaller than those in that for Gaussian smoothing. <i>Conclusion</i>: VBQ smoothing can suppress the change in the relaxation time on the boundary of the tissue and is thus a useful smoothing technique in relaxation time mapping.
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Fukunaga Kota, Enzaki Masahiro, Komi Masanori, Azuma Minako, Hirai Toshinori, Fujiwara Yasuhiro
Japanese Journal of Radiological Technology 79 ( 7 ) 663 - 673 2023.7
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japanese Society of Radiological Technology
<i>Purpose</i>: Three-dimensional (3D) quantification using an interleaved Look-Locker acquisition sequence with a T<sub>2</sub> preparation pulse (QALAS) is a quantitative sequence used to measure relaxation times. The accuracy of the relaxation time measurement of 3D-QALAS at 3.0 T and the bias of 3D-QALAS have not yet been assessed. The purpose of this study was to clarify the accuracy of the relaxation time measurements using 3D-QALAS at 3.0 T MRI. <i>Methods</i>: The accuracy of the T<sub>1</sub> and T<sub>2</sub> values for 3D-QALAS was evaluated using a phantom. Subsequently, the T<sub>1</sub> and T<sub>2</sub> values and proton density of the brain parenchyma in healthy subjects were measured using 3D-QALAS and compared with those of 2D multi-dynamic multi-echo (MDME). <i>Results</i>: In the phantom study, the average T<sub>1</sub> value of 3D-QALAS was 8.3% prolonged than that for conventional inversion recovery spin-echo; the average T<sub>2</sub> value for 3D-QALAS was 18.4% shorter than that for multi-echo spin-echo. The in vivo assessment showed that the mean T<sub>1</sub> and T<sub>2</sub> values and PD for 3D-QALAS were prolonged by 5.3%, shortened by 9.6%, and increased by 7.0%, respectively, compared with those for 2D-MDME. <i>Conclusion</i>: Although 3D-QALAS at 3.0 T has high accuracy T<sub>1</sub> value, which is less than 1000 ms, the T<sub>1</sub> value could be overestimated for tissues with it longer than that T<sub>1</sub> value. The T<sub>2</sub> value for 3D-QALAS could be underestimated for tissues with T<sub>2</sub> values, and this tendency increases with longer T<sub>2</sub> values.
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A clear presentation of intracranial hypostasis on PMCT Reviewed
Shinkawa N., Imada M., Azuma M., Shinkawa N., Yukawa N.
Journal of Forensic and Legal Medicine 97 102540 2023.7
Language：English Publishing type：Research paper (scientific journal) Publisher：Journal of Forensic and Legal Medicine
Intracranial hypostasis is a common postmortem change evident on postmortem CT (PMCT), but can be readily misinterpreted as subdural hematoma by inexperienced physicians. Although PMCT is necessarily lacking contrast enhancement, we reconstructed hypostatic sinuses into three-dimensional images resembling the results of in vivo venography. This simple methodology facilitates easy recognition of intracranial hypostasis.
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Brain structural changes in patients with chronic methylmercury poisoning in Minamata. Reviewed
Hirai T, Abe O, Nakamura M, Inui S, Uetani H, Ueda M, Azuma M
Brain research 1805 148278 2023.4
Language：English Publishing type：Research paper (scientific journal) Publisher：Brain Research
Exploratory whole-brain studies in patients suffering from methylmercury (MeHg) poisoning have not been conducted. We aimed to evaluate the neuroanatomical differences between patients with chronic MeHg poisoning and healthy volunteers via magnetic resonance (MR) imaging. Patients included in this case-control study were divided into three categories based on whether MeHg exposure occurred in utero, under 15 years of age, or over 15 years of age, as fetal-, pediatric-, and adult-type patients, respectively. This study analyzed MR imaging data from 10 patients each of fetal, pediatric, and adult types of chronic MeHg poisoning in Minamata and corresponding 53, 37, and 15 age- and sex-matched healthy volunteers. Whole-brain voxel-based morphometry (VBM) analysis was used to determine the volumetric gray and white matter (GM and WM) differences in patients with chronic MeHg poisoning. Compared to healthy individuals, VBM revealed a significant reduction in GM in the cerebellar and calcarine areas in pediatric- and adult-type cases and in the thalamus of fetal-type cases. A significant reduction in WM volume was also noted in the cerebral and the cerebellar regions, especially in pediatric-type cases. Patients with chronic MeHg poisoning develop structural differences in the GM of the calcarine, the cerebellum, and the thalamus and in the WM of the cerebrum and cerebellum. These changes can appear, depending on the timing of MeHg exposure.
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Uetani H, Azuma M, Khant ZA, Watanabe Y, Kudo K, Kadota Y, Yokogami K, Takeshima H, Kuroda JI, Shinojima N, Hamasaki T, Mukasa A, Hirai T
Journal of computer assisted tomography 47 ( 4 ) 659 - 665 2023.2
Language：English Publishing type：Research paper (scientific journal) Publisher：Journal of Computer Assisted Tomography
Purpose This study aimed to investigate the most useful clinical and magnetic resonance imaging (MRI) parameters for differentiating isocitrate dehydrogenase (IDH)-mutant and-wildtype glioblastomas in the 2016 World Health Organization Classification of Tumors of the Central Nervous System. Methods This multicenter study included 327 patients with IDH-mutant or IDH-wildtype glioblastoma in the 2016 World Health Organization classification who preoperatively underwent MRI. Isocitrate dehydrogenase mutation status was determined by immunohistochemistry, high-resolution melting analysis, and/or IDH1/2 sequencing. Three radiologists independently reviewed the tumor location, tumor contrast enhancement, noncontrast-enhancing tumor (nCET), and peritumoral edema. Two radiologists independently measured the maximum tumor size and mean and minimum apparent diffusion coefficients of the tumor. Univariate and multivariate logistic regression analyses with an odds ratio (OR) were performed. Results The tumors were IDH-wildtype glioblastoma in 306 cases and IDH-mutant glioblastoma in 21. Interobserver agreement for both qualitative and quantitative evaluations was moderate to excellent. The univariate analyses revealed a significant difference in age, seizure, tumor contrast enhancement, and nCET (P < 0.05). The multivariate analysis revealed significant difference in age for all 3 readers (reader 1, odds ratio [OR] = 0.960, P = 0.012; reader 2, OR = 0.966, P = 0.048; reader 3, OR = 0.964, P = 0.026) and nCET for 2 readers (reader 1, OR = 3.082, P = 0.080; reader 2, OR = 4.500, P = 0.003; reader 3, OR = 3.078, P = 0.022). Conclusions Age and nCET are the most useful parameters among the clinical and MRI parameters for differentiating IDH-mutant and IDH-wildtype glioblastomas.
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Watanabe T, Uehara H, Takeishi G, Chuman H, Azuma M, Yokogami K, Takeshima H
World neurosurgery 170 e817 - e826 2023.2
Language：English Publishing type：Research paper (scientific journal) Publisher：World Neurosurgery
Objective: Craniopharyngiomas remain surgically challenging because of the strong adhesion to vital neurovascular structures. We propose a system for the selection of surgical approaches based on the optic recess (OR) displacement pattern to facilitate surgical planning and obtain optimum visual and endocrinologic outcomes. Methods: Craniopharyngiomas were divided into 3 types based on the OR displacement pattern: superior, anterior, and involvement types. Selected surgical approaches and patient outcome were retrospectively reviewed according to these classifications. Visual and endocrinologic outcomes were compared among the groups. Results: This study included 26 patients with primary craniopharyngiomas who underwent surgery at our institution, classified into 11 anterior, 11 superior, and 4 involvement types. The extended endoscopic endonasal approach provided excellent exposure inferodorsal aspect of the chiasm for manipulation of the dissection plane in the anterior and superior types with midline location. A unilateral subfrontal approach was required for tumor of the superior type with lateral extension. An interhemispheric translamina terminalis approach could provide safe dissection under direct vision of strong adhesion at the superior aspect of the chiasm in the involvement type. Visual and endocrinologic outcomes were better in the involvement type compared with the superior and anterior types. Visual outcome was significantly correlated with preoperative visual function. Conclusions: Craniopharyngiomas with the involvement type are indicated for the translamina terminalis approach to achieve the best visual and endocrinologic outcome. Our classification of the OR displacement pattern is useful to select the optimal surgical approach for craniopharyngiomas more accurately and concisely, especially in cases with third ventricular extension.
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Nakagawa M., Nakaura T., Yoshida N., Azuma M., Uetani H., Nagayama Y., Kidoh M., Miyamoto T., Yamashita Y., Hirai T.
Academic Radiology 30 ( 1 ) 83 - 92 2023.1
Language：English Publishing type：Research paper (scientific journal) Publisher：Academic Radiology
Rationale and Objectives: To evaluate the performance of a machine learning method to differentiate malignant from benign soft tissue tumors based on textural features on multiparametric magnetic resonance imaging (mpMRI). Materials and Methods: We enrolled 163 patients with soft tissue tumors whose diagnosis was pathologically proven (71 malignant, 92 benign). All patients underwent mpMRI. Twelve histographic and textural parameters were assessed on T1-weighted imaging (T1WI), T2-weighted imaging, diffusion-weighted imaging, apparent diffusion coefficient maps, and contrast-enhanced T1WI imaging. We compared mean signals of all sequences from the malignant and benign tumors using Welch's t-test. Prediction models were developed via a machine learning technique (support vector machine) using textural features of each sequence, clinical information (sex + age + tumor size), and the combined model incorporating all features. Areas under the receiver operating characteristic curves (AUCs) of these models were calculated using fivefold cross validation. Results: The diagnostic ability of clinical information model (AUC 0.85) was not inferior to the model with textural features of each sequence (AUC 0.79–0.84). The combined model showed the highest diagnostic ability (AUC 0.89). The AUC of the combined model (0.89) was comparable to those of two board-certified radiologists (0.89 and 0.87). Conclusions: Machine learning methods based on textural features on mpMRI and clinical information offer adequate diagnostic performance to differentiate between malignant and benign soft tissue tumors.
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Yamada A., Kinoshita M., Kamimura S., Jinnouchi T., Azuma M., Yamashita S., Yokogami K., Takeshima H., Moritake H.
Pediatric Hematology and Oncology 40 ( 7 ) 629 - 642 2023
Language：English Publishing type：Research paper (scientific journal) Publisher：Pediatric Hematology and Oncology
Atypical teratoid/rhabdoid tumor (AT/RT) is a rare aggressive central nervous system tumor that typically affects children under three years old and has poor survival with a high risk for neurologic deficits. The primary purpose of this study was to successfully treat the disease and delay or avoid whole-brain radiotherapy for children with AT/RT. A retrospective analysis was performed for six children diagnosed with AT/RT and treated with multimodal treatment at a single institute between 2014 and 2020. Furthermore, germline SMARCB1 aberrations and MGMT methylation status of the tumors were analyzed. One patient who did not receive a modified IRS-III regimen replaced with ifosphamide, carboplatin, and etoposide (ICE) in induction chemotherapy was excluded from this analysis. Five patients who received ICE therapy were under three years old. After a surgical approach, they received intensive chemotherapy and high-dose chemotherapy with autologous peripheral blood stem cell transplantation (HDCT/autoPBSCT) followed by intrathecal topotecan maintenance therapy. Three patients underwent single HDCT/autoPBSCT, and the other two received sequential treatment. Two patients with germline SMARCB1 aberrations and metastases died of progressive AT/RT or therapy-related malignancy, while 3 with localized tumors without germline SMARCB1 aberrations remained alive. One survivor received local radiotherapy only, while the other two did not undergo radiotherapy. All three surviving patients were able to avoid whole-brain radiotherapy. Our results suggest that AT/RT patients with localized tumors without germline SMARCB1 aberrations can be rescued with multimodal therapy, including induction therapy containing ICE followed by HDCT/autoPBSCT and intrathecal topotecan maintenance therapy without radiotherapy. Further large-scale studies are necessary to confirm this hypothesis.
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Kai K., Hamada T., Sakae T., Sato Y., Hiyoshi M., Inomata M., Suzuki Y., Nakamura S., Azuma M., Nanashima A.
Clinical Journal of Gastroenterology 2023
Language：English Publishing type：Research paper (scientific journal) Publisher：Clinical Journal of Gastroenterology
A 48-year-old woman underwent transcatheter arterial embolization (TAE) for a splenic artery aneurysm, which resulted in a partial splenic infarction in the middle lobe. Five years after TAE, a 20-mm diameter mass in the noninfarcted area of the spleen was detected on imaging, which grew to 25 mm in diameter after 6 months. MRI after gadolinium administration showed a 35 × 34 mm mass within the superior pole and 15 × 12 mm mass within the inferior pole. The patient underwent laparoscopic splenectomy and had an uneventful postoperative recovery. No evidence of recurrence was observed during the 2-year follow-up period after surgery. The mass was pathologically confirmed to be sclerosing angiomatoid nodular transformation (SANT) of the spleen. While some studies hypothesize that SANT is a response to vascular injury or trauma, to the best of our knowledge, there have been no previous reports of SANT occurring after procedures directly affecting splenic blood flow. Additionally, multifocal SANTs are reported to be very rare, accounting for only 4.7% of all reported SANTs of the spleen. We highlight a rare course of SANT of the spleen and discuss the possible relationship between blood flow abnormalities and the appearance of SANT.
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Lymphomas of Central Nervous System Reviewed
Yokogami K., Azuma M., Takeshima H., Hirai T.
Advances in experimental medicine and biology 1405 527 - 543 2023
Language：English Publishing type：Research paper (scientific journal) Publisher：Advances in experimental medicine and biology
Central nervous system (CNS) lymphoma consists of primary central nervous system lymphoma (PCNSL) and secondary CNS involvement by systemic lymphoma. This chapter focuses on the former. PCNSL is a relative rare disease, accounting for approximately 2.4-4.9% of all primary CNS tumors. It is an extra-nodal variant of non-Hodgkin's lymphoma (NHL), confined to the brain, leptomeninges, spinal cord, and eyes, with no systemic involvement. Recently, elderly patients (≥ 60 years) are increasing. Histologically, B cell blasts, which originate from late germinal center exit B cell, are growing and homing in CNS. Immunohistochemically, these cells are positive for PAX5, CD19, CD20, CD22, and CD79a. PCNSL shows relatively characteristic appearances on CT, MR imaging, and PET. Treatment first line of PCNSL is HD-MTX-based chemotherapy with or without rituximab and irradiation. Severe side-effect of this treatment is delayed onset neurotoxicity, which cause of cognitive impairment. Therefore, combined chemotherapy alone or chemotherapy with reduced-dose irradiation is more recommended for elderly patients. There is no established standard care for relapse of the PCNSLs. Temsirolimus, lenalidomide, temozolomide, and Bruton's tyrosine kinase (BTK) inhibitor ibrutinib are candidates for refractory patients. The prognosis of PCNSL has significantly improved over the last decades (median OS: 26 months, 5-year survival: 31%). Younger than 60 age and WHO performance status less than < or = 1 are associated with a significantly better overall survival.
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特集 ビギナーのための頭部画像診断 -Q＆Aアプローチ- 2023 所見別 小脳橋角部腫瘤はどのように考えればよいですか? Reviewed
東 美菜子
画像診断 43 ( 1 ) 72 - 73 2022.12
Language：English Publishing type：Research paper (scientific journal) Publisher：学研メディカル秀潤社
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Novel Mathematical Diagnostic Analysis of Malignant Biliary Stenosis Using Magnetic Resonance Cholangiography in Patients Undergoing Pancreaticoduodenectomy. Reviewed
Nanashima A, Komi M, Imamura N, Hiyoshi M, Hamada T, Tsuchimochi Y, Ichiki N, Enzaki M, Azuma M
Cancer diagnosis & prognosis 2 ( 6 ) 668 - 680 2022.11
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Yoshida N, Nakaura T, Morita K, Yoneyama M, Tanoue S, Yokota Y, Uetani H, Nagayama Y, Kidoh M, Azuma M, Hirai T
European journal of radiology 155 110489 2022.10
Language：English Publishing type：Research paper (scientific journal) Publisher：European Journal of Radiology
Purpose: To evaluate diffusion-weighted imaging (DWI) using echo planar imaging (EPI) with compressed SENSE (EPICS) of the head and neck magnetic resonance imaging (MRI). Method: We retrospectively observed 32 patients who underwent head and neck DWI according to either the conventional method (SENSE, reduction factor = 2), fast scanning method (SENSE, reduction factor = 4), or fast scanning method with EPICS (EPICS, reduction factor = 4). For quantitative analysis, contrast-to-noise-ratio (CNR), apparent diffusion coefficient (ADC) values, geometric distortion, and coefficient of variations (CV) were measured and compared. For qualitative analysis, all images were independently and blindly evaluated by two board-certified radiologists. Results: EPICS revealed the higher CNR between all location compared to those of SENSE with reduction factor = 4. Distortion in the anterior-posterior direction was significantly lower on EPICS than on the conventional scan (p = 0.02). A comparison between the ADC values of the EPICS and conventional scan revealed no significant differences. The CV was significantly lower for EPICS than the conventional scan [DWI: 0.22 (IQR: 0.15–0.30) vs 0.32 (IQR: 0.24–0.40), p = 0.02]. Conclusions: Compressed SENSE combined with the high acceleration factor can improve image quality, homogeneity, and distortion in the head and neck DWI maintaining ADC values and the scan time duration.
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Uetani H., Nakaura T., Kitajima M., Morita K., Haraoka K., Shinojima N., Tateishi M., Inoue T., Sasao A., Mukasa A., Azuma M., Ikeda O., Yamashita Y., Hirai T.
European Radiology 32 ( 7 ) 4527 - 4536 2022.7
Language：English Publishing type：Research paper (scientific journal) Publisher：European Radiology
Objectives: This study aimed to evaluate the efficacy of a combined wavelet and deep-learning reconstruction (DLR) method for under-sampled pituitary MRI. Methods: This retrospective study included 28 consecutive patients who underwent under-sampled pituitary T2-weighted images (T2WI). Images were reconstructed using either the conventional wavelet denoising method (wavelet method) or the wavelet and DLR methods combined (hybrid DLR method) at five denoising levels. The signal-to-noise ratio (SNR) of the CSF, hypothalamic, and pituitary images and the contrast between structures were compared between the two image types. Noise quality, contrast, sharpness, artifacts, and overall image quality were evaluated by two board-certified radiologists. The quantitative and the qualitative analyses were performed with robust two-way repeated analyses of variance. Results: Using the hybrid DLR method, the SNR of the CSF progressively increased as denoising levels increased. By contrast, with the wavelet method, the SNR of the CSF, hypothalamus, and pituitary did not increase at higher denoising levels. There was a significant main effect of denoising methods (p < 0.001) and denoising levels (p < 0.001), and an interaction between denoising methods and denoising levels (p < 0.001). For all five qualitative scores, there was a significant main effect of denoising methods (p < 0.001) and an interaction between denoising methods and denoising levels (p < 0.001). Conclusions: The hybrid DLR method can provide higher image quality for T2WI of the pituitary with compressed sensing (CS) than the wavelet method alone, especially at higher denoising levels. Key Points: •The signal-to-noise ratios of cerebrospinal fluid progressively increased with the hybrid DLR method, with an increase in the denoising level for cerebrospinal fluid in pituitary T2WI with CS. •The signal-to-noise ratios of cerebrospinal fluid using the conventional wavelet method did not increase at higher denoising levels. •All qualitative scores of hybrid deep-learning reconstructions at all denoising levels were higher than those for the wavelet denoising method.