Details of a Researcher - Jinzaki, Masahiro

Papers - Jinzaki, Masahiro

Division display 121 - 140 of about 556 ／ All the affair displays >>

Pelvic floor morphology in the standing position using upright computed tomography: age and sex differences

Narita K., Yamada Y., Yamada M., Yokoyama Y., Nakahara T., Jinzaki M.

International Urogynecology Journal (International Urogynecology Journal) 31 ( 11 ) 2387 - 2393 2020

ISSN 09373462

© 2020, The International Urogynecological Association. Introduction and hypothesis: This study was aimed at comparing pelvic floor parameters between the standing and supine positions using upright computed tomography (CT) and evaluating the effects of sex and age in normal healthy volunteers. Methods: In total, 139 volunteers (70 men, mean 46.7 years; 69 women, mean 47.3 years) underwent both upright CT in the standing position and conventional CT in the supine position. The distances from the bladder neck to the pubococcygeal line (PCL) and anorectal junction (ARJ), defined as the posterior aspect of the puborectalis muscle, to PCL were measured. The length, width, and area of the levator hiatus (LH) were measured on oblique axial images. Results: The bladder neck (men, 22.2 ± 4.9 mm vs 28.3 ± 5.3 mm; women, 9.0 ± 5.1 mm vs 19.0 ± 4.0 mm) and ARJ (men, −18.8 ± 5.5 mm vs −12.1 ± 5.1 mm; women, −20.0 ± 4.7 mm vs −11.2 ± 4.3 mm) were significantly lower in the standing position than in the supine position (all p < 0.0001). The LH area (men, 1,990 ± 380 mm2 vs 1,697 ± 329 mm2; women, 2,284 ± 344 mm2 vs 1,811 ± 261 mm2) was significantly larger in the standing position (both p < 0.0001). Differences in all parameters between the standing and supine positions were larger in women than in men. ARJ in women showed a significant tendency to descend with age only in the standing position (r = −0.29, p = 0.017). Conclusions: The bladder neck and ARJ descend and the LH area enlarges in the standing position. Pelvic floor mobility is greater in women than in men. Descent of the ARJ in the standing position is associated with aging in women.

Access to Document (DOI)

Analysis of collateral lymphatic circulation in patients with lower limb lymphedema using magnetic resonance lymphangiography

Soga S., Onishi F., Jinzaki M., Mikoshi A., Minabe T., Shinmoto H.

Journal of Vascular Surgery: Venous and Lymphatic Disorders (Journal of Vascular Surgery: Venous and Lymphatic Disorders) 9 ( 2 ) 471 - 481.e1 2020

ISSN 2213333X

© 2020 Society for Vascular Surgery Objective: Although the development of lymphatic collaterals is expected following lymphedema, little is known about the anatomic details of such compensatory pathways or their association with symptoms. Magnetic resonance lymphangiography (MRL) has been shown to be superior to lymphoscintigraphy and indocyanine green lymphography in visualizing lymphatics. This study aimed to analyze MRL images of lower limbs to elucidate the patterns of lymphatic collateral formation and their association with the clinical stages of lymphedema. Methods: We enrolled 56 consecutive patients (112 lower limbs) with lymphedema who underwent MRL. Two radiologists performed a consensus reading of MRL images for the presence or absence of collateral lymphatic pathways, and the results were compared with the clinical stages. Furthermore, the frequency of abnormal MRL findings in 43 asymptomatic lower limbs of patients with unilateral lymphedema was analyzed and compared with that in the 69 symptomatic lower limbs of the patients. The imaging findings were also compared with the cause of lymphedema. Results: All three collateral pathways (anterolateral, deep, and posteromedial lymphatics) were visualized at a higher (P <.05) frequency in stage II than in stage 0 lower limbs. The frequency of visualization of the three collaterals was significantly higher in symptomatic (stages I-III) lower limbs than in asymptomatic (stage 0) lower limbs. Most (76.8%) of the symptomatic limbs exhibited at least one of these collaterals, and the frequency was significantly higher than in the asymptomatic limbs (P <.001). Most (81.4%) of the asymptomatic (stage 0) lower limbs had at least one abnormal finding in terms of lymphatic circulation, although this proportion was significantly lower compared with the symptomatic limbs (98.6%). The collaterals tended to appear less frequently in primary lymphedema than in secondary lymphedema, reaching statistical significance in the posteromedial lymphatics. Conclusions: These results suggested that the two superficial lymphatic groups and the deep lymphatic system act as major collaterals of the lower limbs in patients with lymphedema. Furthermore, MRL of most patients with unilateral lymphedema demonstrated abnormal findings, including collateral formation, not only in the affected lower limb but also in the asymptomatic lower limb. In primary lymphedema, the collaterals may appear less frequently than in secondary lymphedema. Collaterals should be taken into consideration in planning the site of lymphaticovenous anastomosis and assessing disease progression. MRL can visualize preclinical alterations in lymphatic flow and compensatory pathways; therefore, we expect that it will be useful for the early diagnosis of lymphedema.

Access to Document (DOI)

Quantitative analysis of the anatomical changes in the scalp and hair follicles in androgenetic alopecia using magnetic resonance imaging

Soga S., Koyama T., Mikoshi A., Jinzaki M., Arafune T., Kawashima M., Kobayashi K., Shinmoto H.

Skin Research and Technology (Skin Research and Technology) 27 ( 1 ) 56 - 61 2020

ISSN 0909752X

© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd Background: Although the structural changes of the scalp in androgenetic alopecia (AGA) have been reported, these changes have been poorly understood. It is expected that modern MRI would visualize the scalp anatomy in vivo. This study aimed to explore whether AGA causes (a) changes in the thickness of the scalp, (b) anatomical changes in the hair follicles, and (c) changes in the signal intensity of MRI. Materials and Methods: Twenty-seven volunteers underwent MRI for hair and scalp (MRH) and were categorized into two according to the Hamilton-Norwood Scale: the “AGA group” and the “normal group.” Two radiologists analyzed the thickness and signal intensity of the scalp, and the depth of hair follicles. These measurements were compared between the two groups. Results: The thickness of the hypodermis and the entire scalp was significantly thinner in the AGA group than in the control group. The AGA group had significantly shallower depth of hair follicles and relative depth of the hair follicles to that of the entire scalp than the normal group. The hypodermis showed higher signal intensity in the AGA group than the normal group. Conclusion: MRH allowed noninvasive visualization of the scalp anatomy and demonstrated the thinner nature of the entire scalp and hypodermis, along with the shallower depth of the hair follicles in the AGA group in comparison to the normal group. Additionally, MRH demonstrated the increased MR signal intensity in the scalp associated with AGA. MRH may be a promising new method for quantitative and objective analyses of AGA.

Access to Document (DOI)

Differences in Lung and Lobe Volumes between Supine and Standing Positions Scanned with Conventional and Newly Developed 320-Detector-Row Upright CT: Intra-Individual Comparison

Yamada Y., Yamada M., Yokoyama Y., Tanabe A., Matsuoka S., Niijima Y., Narita K., Nakahara T., Murata M., Fukunaga K., Chubachi S., Jinzaki M.

Respiration (Respiration) 99 ( 7 ) 598 - 605 2020

ISSN 00257931

© 2020 Background: No clinical studies to date have compared unilateral lung or lobe volumes between the supine and standing positions. Objectives: To compare lung/lobe volumes on computed tomography (CT) between these two positions and evaluate the correlation between the total lung volume and total lung capacity (TLC) on pulmonary function tests (PFTs). Methods: Thirty-two asymptomatic volunteers underwent both conventional CT (supine position) and upright CT (standing position), during deep inspiration breath-hold, and PFTs on the same day. We measured lung/lobe volumes on CT in each position. Paired t tests were used for statistical analysis. Results: The volumes of the total lung (10.9% increase), right lung (10.3% increase), right upper lobe (8.6% increase), right lower lobe (14.6% increase), left lung (11.6% increase), left upper lobe (7.1% increase), and left lower lobe (16.0% increase) were significantly greater in the standing position than in the supine position (all p < 0.0001). The right middle lobe volume was similar between the two positions (p = 0.16). Intraclass correlation coefficients for agreement between total lung volumes on CT in the supine/standing positions and the TLC on PFT were 0.891/0.938, respectively. Conclusions: While the volumes of the bilateral upper and lower lobes and bilateral lungs were significantly greater in the standing than in the supine position, with lower lobes showing larger changes, the right middle lobe volume did not change significantly between positions. The total lung volume on upright CT in the standing position was more similar to TLC on PFT than that in the supine position.

Access to Document (DOI)

Relationship between hip joint proximity area and sagittal balance parameters: an upright computed tomography study

Kikuchi S., Nakashima D., Yamada Y., Yamada M., Yokoyama Y., Kanaji A., Nakamura M., Nagura T., Jinzaki M.

European Spine Journal (European Spine Journal) 2020

ISSN 09406719

Purpose: A close relationship between sagittal spinal alignment and hip osteoarthritis (OA) has been documented. This study aimed to examine the relationship between hip joint proximity area and sagittal balance parameters in healthy subjects. Methods: This prospective study enrolled 47 healthy volunteers who underwent 320-detector row upright computed tomography. Acquired data were reconstructed in a virtual three-dimensional space. The proximity area was determined by < 1 mm of the Hausdorff distance between the acetabulum and the femoral head. Volunteers were divided into the anterior and posterior proximity groups depending on the position of the closest area. Sagittal balance parameters [sagittal vertical axis (SVA), T1 spinopelvic inclination (T1-SPi), T1-pelvic angle, pelvic tilt, sacral slope, pelvic incidence, lumbar lordosis, thoracic kyphosis), offset distance between the centre of the acoustic meati (CAM) and C7 plumb line (CAM-C7-offset), and offset distance between the CAM and hip axis (HA) (CAM-HA-offset)] were compared between the two groups using independent sample t test. Results: The anterior proximity group (n = 24) had higher SVA (p = 0.016) and T1-Spi (p = 0.015) than the posterior proximity group (n = 23). CAM-HA-offset was higher in the posterior than in the anterior proximity group (p < 0.000). There was no difference in other parameters (p > 0.05). Conclusion: The anterior proximity group had a positive anterior spinal balance; the posterior proximity group may have a more posterior gravity line than the hip joint centre. The anterior spinal balance may contribute to the anterior loading of the hip joint, with known relation with the initiation and onset of hip OA.

Access to Document (DOI)

Projected lung areas using dynamic X-ray (DXR)

Hino T., Hata A., Hida T., Yamada Y., Ueyama M., Araki T., Kamitani T., Nishino M., Kurosaki A., Jinzaki M., Ishigami K., Honda H., Hatabu H., Kudoh S.

European Journal of Radiology Open (European Journal of Radiology Open) 7 2020

Background: Dynamic X-ray (DXR) provides images of multiple phases of breath with less radiation exposure than CT. The exact images at end-inspiratory or end-expiratory phases can be chosen accurately. Purpose: To investigate the correlation of the projected lung area (PLA) by dynamic chest X-ray with pulmonary functions. Material and Methods: One hundred sixty-two healthy volunteers who received medical check-ups for health screening were included in this study. All subjects underwent DXR in both posteroanterior (PA) and lateral views and pulmonary function tests on the same day. All the volunteers took several tidal breaths before one forced breath as instructed. The outlines of lungs were contoured manually on the workstation with reference to the motion of diaphragm and the graph of pixel values. The PLAs were calculated automatically, and correlations with pulmonary functions and demographic data were analyzed statistically. Results: The PLAs have correlation with physical characteristics, including height, weight and BMI, and pulmonary functions such as vital capacity (VC) and forced expiratory volume in one second (FEV ). VC and FEV revealed moderate correlation with the PLAs of PA view in forced inspiratory phase (VC: right, r = 0.65; left, r = 0.69. FEV1: right, r = 0.54; left, r = 0.59). Multivariate analysis showed that body mass index (BMI), sex and VC were considered independent correlation factors, respectively. Conclusion: PLA showed statistically significant correlation with pulmonary functions. Our results indicate DXR has a possibility to serve as an alternate method for pulmonary function tests in subjects requiring contact inhibition including patients with suspected or confirmed covid-19. 1 1

Access to Document (DOI)

MR Imaging of Mushroom-like Skin Adnexal Tumors in the Scalp: A Report of Two Cases

Arai Manabu, Nozaki Taiki, Matsusako Masaki, Zenke Yukari, Arai Satoru, Matsui Mizuko, Suzuki Koyu, Jinzaki Masahiro, Kurihara Yasuyuki

Magnetic Resonance in Medical Sciences (Japanese Society for Magnetic Resonance in Medicine) 19 ( 3 ) 282 - 285 2020

ISSN 13473182

<p>Few studies had been published regarding imaging findings of skin adnexal tumors. We experienced two giant cases of them with a characteristic mushroom-like growth pattern. MRI showed a circumscribed mushroom-like shaped mass extruding from the subcutaneous tissue with microcystic lesions. Although differentiation between benignancy and malignancy may be difficult by radiological examinations, MRI may be helpful to identify its origin and differentiate soft tissue tumors with skin adnexal tumors in having these imaging findings.</p>

Diagnosis, prevention, and treatment of cardiovascular diseases in people with type 2 diabetes and prediabetes: a consensus statement jointly from the Japanese Circulation Society and the Japan Diabetes Society

Araki E., Tanaka A., Inagaki N., Ito H., Ueki K., Murohara T., Imai K., Sata M., Sugiyama T., Ishii H., Yamane S., Kadowaki T., Komuro I., Node K., Amano T., Anzai T., Babazono T., Emoto M., Fukuda K., Hagiwara N., Hirata K.i., Ikari Y., Ikeda T., Izumi C., Jinzaki M., Kaneto H., Katagiri H., Kimura T., Kobayashi Y., Maemura K., Matoba S., Minamino T., Mitani Y., Miura S.i., Morino Y., Nakamura J., Nishio Y., Ogawa W., Ohishi M., Okura H., Ono M., Sakata Y., Sato A., Shimada A., Shimizu W., Shimomura I., Shiojima I., Takamura M., Takeishi Y., Tanemoto K., Tanizawa Y., Terauchi Y., Tobe K., Tetsuou Y., Watada H., Yamauchi T., Yano M., Yoshioka N.

Diabetology International (Diabetology International) 2020

ISSN 21901678

Access to Document (DOI)

A Case of Head and Neck Lymphatic Malformation in which Sclerotherapy with Polidocanol was Useful for Hemostasis

Kikuchi Akira, Aramaki-Hattori Noriko, Inoue Masanori, Ozawa Hiroyuki, Nakamura Shintaro, Sakai Shigeki, Okabe Keisuke, Nakatsuka Seishi, Jinzaki Masahiro, Kishi Kazuo

International Journal of Surgical Wound Care (Japan Society for Surgical Wound Care) 1 ( 1 ) 38 - 41 2020

Lymphatic malformations that occur in the head and neck are often difficult to treat. Sclerotherapy using polidocanol, which has little tissue damage, can be treated with minimal dysfunction and complications. In particular, it is considered an effective treatment for superficial lesions that bleed from the mucosal surface. In this study, we performed sclerotherapy using polidocanol for a 17-year-old woman with lymphatic malformations with blood containing lymphorrhea in the pharynx and larynx. A total of 3 sclerotherapy treatments were performed, and lesion reduction and bloody lymphorrhea control were observed. At 1 year after treatment, the course of treatment was good with no re-enlargement of the lesions.

Lymphatic Intervention for Abdominal Lymphatic Leakage

Inoue Masanori, Torikai Hideyuki, Ito Nobutake, Tamura Masashi, Ogawa Ryo, Nakatsuka Seishi, Jinzaki Masahiro

The Official Journal of the Japanese Society of Interventional Radiology (The Japanese Society of Interventional Radiology) 34 ( 3 ) 187 - 192 2020

ISSN 1340-4520

One of the important functions of the lymphatic system is maintenance of fluid balance, and lymphatic leakage after surgery potentially becomes a critical condition.<BR>Interventional techniques could not treat lymphatic leakage effectively mostly due to the lack of clinical imaging. However, the recently developed intranodal lymphangiography provides new insight into lymphatic intervention. At first, thoracic duct embolization has become the method of choice for the treatment of patients with chylothorax. Abdominal lymphatic leakage as a complication of abdominal and pelvic surgery is an uncommon but difficult-to-treat condition when conservative measures have failed. Embolization and sclerotherapy are also very useful for refractory lymphatic leakage. These current advances will open up new treatments and diag-nostic opportunities for abdominal lymphatic leakage.

Prediction of extraprostatic extension by MRI tumor contact length: difference between anterior and posterior prostate cancer

Matsumoto K., Akita H., Narita K., Hashiguchi A., Takamatsu K., Takeda T., Kosaka T., Mizuno R., Kikuchi E., Oya M., Jinzaki M.

Prostate Cancer and Prostatic Diseases (Prostate Cancer and Prostatic Diseases) 22 ( 4 ) 539 - 545 2019.12

ISSN 13657852

© 2019, Springer Nature America, Inc. Background: Tumor contact length (TCL) is defined as the extent of contact between prostate cancer and the prostatic capsule, and its predictive value for microscopic extraprostatic extension (EPE) has been reported. However, the impact of the zonal origin (anterior or posterior tumor) of the tumor on the diagnosis of EPE is controversial. Methods: We retrospectively analyzed the records of 233 consecutive patients who underwent preoperative MRI and radical prostatectomy. We designated their tumors as anterior or posterior, and evaluated the correlation between the TCL measured by MRI and microscopic EPE in the radical prostatectomy specimen. Then, we created the predicted probability curves for EPE versus TCL for anterior and posterior prostate cancer. Results: There were 109 patients (47%) with an anterior tumor and 124 patients (53%) with a posterior tumor. Postoperative pathological analysis confirmed pT3 in 18 patients (17%) with an anterior tumor and in 53 patients (43%) with a posterior tumor. Multivariate analysis demonstrated that the zonal origin of the tumor was an independent predictive factor for EPE. We developed separate probability curves of EPE versus TCL for anterior and posterior prostate cancer, which revealed that anterior tumors were less likely to invade the extraprostatic tissues. Among patients whose TCL was 10–20 mm, 9/32 patients (28%) with an anterior tumor had EPE compared with 24/45 patients (53%) with a posterior tumor (p = 0.036). The decision curve of this EPE predictive model had high clinical efficacy. Conclusions: Our results indicate that anterior tumors have more favorable pathological characteristics than posterior tumors with the same TCL measured by MRI. We constructed two separate predicted probability curves for EPE after discriminating anterior and posterior tumors, which will be useful for decision making in clinical practice.

Access to Document (DOI)

Use of CT in a standing position for preoperative evaluation in abdominal incisional hernia: A pilot study

Sakamoto Y., Yamada M., Yamada Y., Yokoyama Y., Kishi K., Jinzaki M.

Journal of plastic, reconstructive & aesthetic surgery : JPRAS (Journal of plastic, reconstructive & aesthetic surgery : JPRAS) 72 ( 12 ) 2019.12

Access to Document (DOI)

Predictive markers for MGMT promoter methylation in glioblastomas

Kanazawa T., Minami Y., Jinzaki M., Toda M., Yoshida K., Sasaki H.

Neurosurgical Review (Neurosurgical Review) 42 ( 4 ) 867 - 876 2019.12

ISSN 03445607

© 2019, Springer-Verlag GmbH Germany, part of Springer Nature. The promoter methylation status of the O6-methylguanine-DNA methyltransferase (MGMT) gene has been described as the most important predictor of chemotherapeutic response and patients’ survival in glioblastomas (GBs). Therefore, prediction of the MGMT promoter methylation status by imaging would help to preoperatively decide the overall treatment strategy as well as surgical strategy. This study aimed to detect imaging parameters to predict MGMT promoter methylation in GBs by using a commercially available software. We investigated three imaging features (ring enhancement, tumor location, and laterality) and apparent diffusion coefficient (ADC) parameters in 48 newly diagnosed GBs treated at Keio University Hospital in 2006 or later. For ADC, texture analyses were performed. Regions of interest (ROIs) were drawn manually with reference to contrast-enhanced areas, excluding necrotic and cystic regions. Mean ADC value and ADC histogram parameters, including kurtosis, skewness, and entropy, were compared with MGMT promoter methylation. Each parameter was evaluated to determine correlation with MGMT promoter methylation, and the parameters with significant associations with the methylation status were correlated with the MGMT-positive cell ratio determined by immunohistochemistry (IHC) analysis. The mean ADC value and ADC entropy were significantly associated with MGMT promoter methylation. The combination of mean ADC value and ADC entropy predicted MGMT promoter methylation, with a PPV of 81.2% and specificity of 88.9%. The mean ADC value and ADC entropy were negatively correlated with the MGMT-positive cell ratio in the IHC analysis. This study demonstrated that texture analyses of ADC histograms in GBs were predictive of MGMT promoter methylation.

Access to Document (DOI)

Picked-up Knowledge from Foreign Journals 血管周囲の脂肪

中原健裕, 奥田茂男, 陣崎雅弘

画像診断 (学研メディカル秀潤社) 40 ( 1 ) 112 - 114 2019.11

ISSN 0285-0524

Three-dimensional kinematic change of hindfoot during full weightbearing in standing: An analysis using upright computed tomography and 3D-3D surface registration

Kaneda K., Harato K., Oki S., Ota T., Yamada Y., Yamada M., Matsumoto M., Nakamura M., Nagura T., Jinzaki M.

Journal of Orthopaedic Surgery and Research (Journal of Orthopaedic Surgery and Research) 14 ( 1 ) 2019.11

© 2019 The Author(s). Background: Weightbearing of the hindfoot affects positional changes of the ankle joint and subtalar joint (ankle-joint complex [AJC]). However, it is difficult to assess the kinematic changes in the hindfoot in a natural full weightbearing condition using conventional CT or cone beam computed tomography (CT) due to limitations of acquiring foot images under a physiological weightbearing condition using those imaging modalities. Analysis of AJC kinematics using fluoroscopy and 2D-3D registration technique requires data on the number of steps and amount of time to build and match the bones. This study aimed to analyze the effect of full weightbearing on hindfoot motion when standing using upright CT and 3D-3D surface registration. Methods: Forty-eight AJCs of 24 asymptomatic volunteers (13 women, 11 men) were examined under no weightbearing, 50% weightbearing, and single leg full weightbearing conditions while standing. The CT images were acquired from the distal femur to the whole foot using a 320-row upright CT scanner. The condition of each weightbearing stance was measured using a pressure mat. Bone-to-bone rotations of the talus relative to the tibia and calcaneus relative to the talus were evaluated using the surface registration technique. Image quality of the CT and intra- and interobserver reliabilities of the rotation angle were also evaluated. Results: All CT images were excellent or good quality and the intra- and interobserver correlation coefficients for the angle were 0.996 and 0.995, respectively. The motion of the ankle joint and subtalar joint under 50% and 100% weightbearing were as follows (in degrees); the talus plantarflexed (5.1 ± 4.5 and 6.8 ± 4.8), inverted (1.3 ± 1.4 and 2.0 ± 1.6), and internally rotated (2.4 ± 4.2 and 4.3 ± 4.6) relative to the tibia, and the calcaneus dorsiflexed (2.8 ± 1.4 and 3.8 ± 1.7), everted (5.3 ± 2.6 and 8.0 ± 3.6), and externally rotated (3.0 ± 2.0 and 4.1 ± 2.4) relative to the talus, respectively. Conclusions: The effect of weightbearing was clearly identified using an upright CT and the 3D-3D registration technique. Three-dimensional kinematics under static full weightbearing were opposite between the ankle and subtalar joints on their respective axes.

Access to Document (DOI)

Myocardial T1 values in healthy volunteers measured with saturation method using adaptive recovery times for T1 mapping (SMART1Map) at 1.5 T and 3 T

Matsumoto S., Okuda S., Yamada Y., Suzuki T., Tanimoto A., Nozaki A., Jinzaki M.

Heart and Vessels (Heart and Vessels) 34 ( 11 ) 1889 - 1894 2019.11

ISSN 09108327

© 2019, Springer Japan KK, part of Springer Nature. Myocardial T1 mapping is clinically valuable for assessing the myocardium, and modified look-locker inversion-recovery (MOLLI) approaches have been commonly used for measuring myocardial T1 values. To date, several other sequences have been developed for measuring myocardial T1 values, and saturation-recovery-based sequences have been shown to be less dependent on various factors, such as T2 times and magnetization transfer, than inversion-recovery techniques. Systematic differences in T1 values between different sequences have been reported; therefore, definition of the normal range of native T1 values is required before clinical usage can begin. The purpose of this study was to evaluate the reference range and sex dependency of native T1 values in the myocardium measured using one such saturation-recovery sequence, i.e., saturation method using adaptive recovery times for cardiac T1 mapping (SMART1Map). Myocardial T1 values were compared between SMART1Map and MOLLI in 24 young healthy volunteers at 1.5 T and 3 T, and differences in the T1 values between the sexes were assessed. The mean native T1 values in the myocardium were significantly longer with SMART1Map than MOLLI [1530.4 ± 49.2 vs 1222.1 ± 48.9 ms at 3 T (p < 0.001) and 1227.3 ± 41.9 ms vs 1014.8 ± 49.4 ms at 1.5 T (p < 0.001)]. A significant difference between the sexes was observed in the T1 values obtained using each sequence, excluding SMART1Map at 3 T. The SMART1Map has a potential advantage to overcome the shortcoming of MOLLI, which underestimates T1 values; however, the sex-dependent difference remains obscure using SMART1Map.

Access to Document (DOI)

Usefulness of contrast-enhanced ultrasonography for diagnosis of renal cell carcinoma in dialysis patients: Comparison with computed tomography

Hashimoto M., Ohkuma K., Akita H., Yamada Y., Nakatsuka S., Mizuno R., Oya M., Jinzaki M.

Medicine (United States) (Medicine (United States)) 98 ( 47 ) 2019.11

ISSN 00257974

© 2019 the Author(s). Published by Wolters Kluwer Health, Inc. Aims:To investigate the usefulness of contrast-enhanced ultrasonography for diagnosing renal cell carcinoma (RCC) in dialysis patients.Material and methods:Of 1301 dialysis patients who underwent abdominal computed tomography (CT) between January 2012 and March 2017, 19 were suspected to have solid renal lesions; of these patients, 18 gave consent for and underwent contrast-enhanced ultrasonography with perflubutane in addition to CT; 13 underwent dynamic contrast-enhanced CT, and 5, who could not be administered iodinated contrast media, underwent unenhanced CT. The final diagnoses were based on histopathological findings or the presence/absence of enlargement of the lesion during follow-up.Results:Of the 19 lesions in 18 patients, 14 were diagnosed as RCC and 5 as benign cysts. CT facilitated accurate diagnosis in 10/19 lesions (52.6%) with obvious enhancement (≥20 Hounsfield units [HU]), while definitive diagnosis by CT was difficult in 9 lesions: 2 lesions showed ambiguous enhancement (10-20 HU), 1 lesion was an inflammatory cyst with obvious enhancement, and 6 lesions were assessed by unenhanced CT. Compared with CT, contrast-enhanced ultrasonography allowed more accurate diagnosis (McNemar test, P = .02) in 17/19 lesions (89.5%, 14 RCC and 3 cysts; including all lesions assessed by unenhanced CT and 2 with ambiguous enhancement on CT), with 1 false-positive (inflammatory cyst with hyper-enhancement) and 1 false-negative result due to deep location of the lesion.Conclusions:Contrast-enhanced ultrasonography was useful for the diagnosis of RCC in dialysis patients with suspected solid renal lesions especially when contrast enhancement was not obvious on CT or contrast-enhanced CT could not be performed.

Access to Document (DOI)

A Novel Flow Dynamics Study of the Intracranial Veins Using Whole Brain Four-Dimensional Computed Tomography Angiography

Mizutani K., Arai N., Toda M., Akiyama T., Fujiwara H., Jinzaki M., Yoshida K.

World Neurosurgery (World Neurosurgery) 131 e176 - e185 2019.11

ISSN 18788750

© 2019 Elsevier Inc. Background: The flow dynamics of the intracranial venous channels are fundamentally important for understanding intracranial physiology and pathophysiology. However, the method clinically applicable to the evaluation of the flow dynamics of the intracranial venous system has not been well described in the reported data. We have developed a new method to evaluate intracranial venous flow direction and velocity using 4-dimensional (4D) computed tomography angiography (CTA). The aim of the present study was to verify the accuracy and validity of 4D-CTA in a clinical setting. Methods: We retrospectively analyzed 97 veins from 26 patients (16 cases of arteriovenous shunt disease, 9 intracranial tumor cases, and 1 cerebral aneurysm case) who had undergone both 4D-CTA and conventional digital subtraction angiography (DSA). Using 4D-CTA, we analyzed the time-density curve with gamma distribution extrapolation and obtained the direction of the flow and flow velocity of each vein. The direction of the flow in 4D-CTA was also collated with that obtained using conventional DSA to verify the experimental method. Results: The direction of the flow determined by 4D-CTA was consistent with that of conventional DSA in 94.8% of cases. The average venous flow velocity was 64.3 mm/second and 81.8 mm/second, respectively, in the antegrade and retrograde channels affected by arteriovenous shunts. Conclusions: The present flow analysis using 4D-CTA enabled us to evaluate the direction and velocity of intracranial venous flow. Other than some limitations, the presented method is reliable and its potential for application in clinical settings is promising.

Access to Document (DOI)

Four-dimensional ct analysis using sequential 3d-3d registration

Oki S., Kaneda K., Yamada Y., Yamada M., Morishige Y., Harato K., Matsumura N., Nagura T., Jinzaki M.

Journal of Visualized Experiments (Journal of Visualized Experiments) 2019 ( 153 ) 2019.11

ISSN 1940087X

© 2019 Journal of Visualized Experiments. Four-dimensional computed tomography (4DCT) provides a series of volume data and visualizes joint motions. However, numerical analysis of 4DCT data remains difficult because segmentation in all volumetric frames is time-consuming. We aimed to analyze joint kinematics using a sequential 3D-3D registration technique to provide the kinematics of the moving bone with respect to the fixed bone semiautomatically using 4DCT DICOM data and existing software. Surface data of the source bones are reconstructed from 3DCT. The trimmed surface data are respectively matched with surface data from the first frame in 4DCT. These trimmed surfaces are sequentially matched until the last frame. These processes provide positional information for target bones in all frames of the 4DCT. Once the coordinate systems of the target bones are decided, translation and rotation angles between any two bones can be calculated. This 4DCT analysis offers advantages in kinematic analyses of complex structures such as carpal or tarsal bones. However, fast or large-scale motions cannot be traced because of motion artifacts.

Access to Document (DOI)

特集希少癌に備える-いざという時のための基礎知識後腹膜腫瘍:画像診断

秋田大宇, 池田織人, 陣崎雅弘

臨床泌尿器科 (株式会社医学書院) 73 ( 11 ) 806 - 814 2019.10

ISSN 0385-2393

　 Previous page - Next page 　