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1.
Pol J Radiol ; 88: e562-e573, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38362017

RESUMO

Purpose: To evaluate the feasibility of using a deep learning (DL) model to generate fat-suppression images and detect abnormalities on knee magnetic resonance imaging (MRI) through the fat-suppression image-subtraction method. Material and methods: A total of 45 knee MRI studies in patients with knee disorders and 12 knee MRI studies in healthy volunteers were enrolled. The DL model was developed using 2-dimensional convolutional neural networks for generating fat-suppression images and subtracting generated fat-suppression images without any abnormal findings from those with normal/abnormal findings and detecting/classifying abnormalities on knee MRI. The image qualities of the generated fat-suppression images and subtraction-images were assessed. The accuracy, average precision, average recall, F-measure, sensitivity, and area under the receiver operator characteristic curve (AUROC) of DL for each abnormality were calculated. Results: A total of 2472 image datasets, each consisting of one slice of original T1WI, original intermediate-weighted images, generated fat-suppression (FS)-intermediate-weighted images without any abnormal findings, generated FS-intermediate-weighted images with normal/abnormal findings, and subtraction images between the generated FS-intermediate-weighted images at the same cross-section, were created. The generated fat-suppression images were of adequate image quality. Of the 2472 subtraction-images, 2203 (89.1%) were judged to be of adequate image quality. The accuracies for overall abnormalities, anterior cruciate ligament, bone marrow, cartilage, meniscus, and others were 89.5-95.1%. The average precision, average recall, and F-measure were 73.4-90.6%, 77.5-89.4%, and 78.4-89.4%, respectively. The sensitivity was 57.4-90.5%. The AUROCs were 0.910-0.979. Conclusions: The DL model was able to generate fat-suppression images of sufficient quality to detect abnormalities on knee MRI through the fat-suppression image-subtraction method.

2.
J Comput Assist Tomogr ; 46(3): 455-463, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35467584

RESUMO

MATERIALS AND METHODS: Magnetic resonance imaging around metal joint prostheses including multiacquisition variable-resonance image combination selective at 1.5 T (from April 2014 to August 2020) was retrospectively evaluated by 2 radiologists for detection of abnormal findings (joint effusion, capsular thickening, pericapsular edema, soft-tissue fluid collection, soft-tissue edema, bone marrow edema pattern around the implant [BME pattern], lymphadenopathy, and others) and overall image impression for PJI. Regarding the soft-tissue fluid collection, presence of communication to the joint or capsular-like structure was evaluated. Clinical assessments were recorded. Positive predictive values (PPVs), negative predictive values (NPVs), and odds ratios (ORs) for PJI were calculated for the abnormal findings. Overall image impression for PJI was evaluated. χ2, Fisher exact, t, and Mann-Whitney U tests and receiver operating characteristic analysis were used. Interobserver agreement was assessed with κ statistics. RESULTS: Forty-three joints in 36 patients (mean ± SD age, 75.4 ± 8.8 years; 30 women; hip [n = 29], knee [n = 12], and elbow [n = 2]) were evaluated. Eighteen joints (42%) were clinically diagnosed as PJI. The findings suggesting PJI were capsular thickening (PPV, 70%; NPV, 90%; OR, 20.6), soft-tissue fluid collection (PPV, 81%; NPV, 81%; OR, 19.1), soft-tissue edema (PPV, 67%; NPV, 89%; OR, 17), pericapsular edema (PPV, 76%; NPV, 81%; OR, 13.7), and joint effusion (PPV, 55%; NPV, 100%; OR, 12). Soft-tissue fluid collection without capsular-like structure (PPV, 83%; NPV, 74%; OR, 14.4) or with communication to the joint (PPV, 75%; NPV, 71%; OR, 7.3) suggested PJI. The combinations of joint effusion, capsular thickening, pericapsular edema, soft-tissue fluid collection, and soft-tissue edema highly suggested PJI. Regarding the BME pattern, the combination with soft-tissue edema raised the possibility of PJI (PPV, 73%; NPV, 69%; OR, 5.9). Regarding the interobserver agreements for each abnormal finding, κ values were 0.60 to 0.77. Regarding the overall image impression, weighted κ value was 0.97 and areas under the receiver operating characteristic curve were 0.949 (95% confidence interval, 0.893-1.005) and 0.926 (95% confidence interval, 0.860-0.991) with no significant difference (P = 0.534). CONCLUSIONS: The findings suggesting PJI were capsular thickening, soft-tissue fluid collection, soft-tissue edema, pericapsular edema, and joint effusion. The combinations of them highly suggested PJI. Regarding the BME pattern, the combination with soft-tissue edema raised the possibility of PJI.


Assuntos
Infecções Relacionadas à Prótese , Idoso , Idoso de 80 Anos ou mais , Artefatos , Edema , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Infecções Relacionadas à Prótese/diagnóstico por imagem , Estudos Retrospectivos , Sensibilidade e Especificidade
3.
J Stroke Cerebrovasc Dis ; 28(12): 104397, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31582273

RESUMO

AIM OF THE STUDY: Diffusion-weighted image (DWI) of magnetic resonance imaging (MRI) can reveal high signal lesion in up to 50% of transient ischemic attack (TIA) patients. However, it is not well-known which factors determine developing DWI positivity. In order to answer this question, we analyzed factors relevant to DWI positivity in TIA patients. METHODS: We had 257 stroke patients at a university emergency/neurology wards. They were 140 men, 117 women, mean age 72 (45-88) years. Among them, 24 (9.3%) had TIA (14 men, 10 women, mean age 71 [58-82] years). All patients underwent a 1.5T MRI. In 24 TIA patients, we investigated the following parameters in relation with stroke maturation: ABCD2 score, smoking habits, blood profile, HbA1C, dyslipidemia, coagulation factors, carotid echography, electrocardiography, cardiac echography, chest X-ray, neurological symptom/signs, imaging, and recurrence of neurological symptom on follow-up. RESULTS: In 24 TIA patients, 13 (54%) were DWI positive and 11 (46%) were DWI negative. After an extensive analysis, all parameters were not relevant to DWI positivity except for plasma osmolarity, i.e., plasma osmolarity in DWI positive cases (305.3 mOsm/l) is significantly higher than that in DWI negative cases (301.3 mOsm/l) (P = .0064). As for recurrence, 4 of 24 TIA patients recurred. They were 1 (9.0%) of 11 DWI negative cases and 3 (23.1%) of 13 DWI positive cases. Therefore, DWI positive cases recurred more frequently than DWI negative cases did, although it did not reach statistical significance. CONCLUSIONS: TIA with DWI positivity in our institute was 54%, closely associated with initial dehydration and might predict stroke recurrence.


Assuntos
Desidratação/complicações , Imagem de Difusão por Ressonância Magnética , Ataque Isquêmico Transitório/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Desidratação/sangue , Desidratação/diagnóstico , Desidratação/fisiopatologia , Feminino , Humanos , Ataque Isquêmico Transitório/sangue , Ataque Isquêmico Transitório/etiologia , Masculino , Pessoa de Meia-Idade , Estado de Hidratação do Organismo , Concentração Osmolar , Valor Preditivo dos Testes , Recidiva , Medição de Risco , Fatores de Risco
4.
Neuroradiology ; 59(1): 89-98, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28035426

RESUMO

INTRODUCTION: The characteristics of dementia with Lewy bodies (DLB), Alzheimer's disease (AD) and amnestic mild cognitive impairment (a-MCI) overlap but require different treatments; therefore, it is important to differentiate these pathologies. Assessment of dopamine uptake in the striatum using dopamine transporter (DaT) single-photon emission computed tomography (SPECT) is the gold standard for diagnosing DLB; however, this modality is expensive, time consuming and involves radiation exposure. Degeneration of the substantia nigra nigrosome-1, which occurs in DLB, but not in AD/a-MCI, can be identified by 3T susceptibility-weighted imaging (SWI). Therefore, the aim of this retrospective observational study was to compare SWI with DaT-SPECT for differentiation of DLB from AD/a-MCI. METHODS: SWI data were acquired for patients with clinically diagnosed DLB (n = 29), AD (n = 18), a-MCI (n = 13) and healthy controls (n = 26). Images were analysed for nigrosome-1 degeneration. Diagnostic accuracy was evaluated for DLB, AD and a-MCI compared with striatal dopamine uptake using DaT-SPECT. RESULTS: SWI achieved 90% diagnostic accuracy (93% sensitivity, 87% specificity) for the detection of nigrosome-1 degeneration in DLB and not in AD/a-MCI as compared with 88.3% accuracy (93% sensitivity, 84% specificity) using DaT-SPECT. CONCLUSIONS: SWI nigrosome-1 evaluation was useful in differentiating DLB from AD/a-MCI, with high accuracy. This less invasive and less expensive method is a potential alternative to DaT-SPECT for the diagnosis of DLB.


Assuntos
Mapeamento Encefálico/métodos , Doença por Corpos de Lewy/diagnóstico por imagem , Doença por Corpos de Lewy/patologia , Imageamento por Ressonância Magnética/métodos , Substância Negra/diagnóstico por imagem , Substância Negra/patologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
Kyobu Geka ; 70(12): 995-999, 2017 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-29104198

RESUMO

We evaluated the efficacy of our sternum closure technique. Out of the 101 patients who underwent cardiovascular surgery at our department, 36 patients underwent sternum closure using ultra-high molecular weight polyethylene tape (NT) with Super FIXSORB MX40 (SF40) insertion into the sternum manubrium (group A) and 19 patients used NT with Sterna Lock Blu (group B). None of the patients had sternum disruption. Postoperative computed tomography scan revealed comparable effect in preventing transverse and anterior-posterior sternal displacement between the 2 groups. The use of NT with SF40 insertion into the sternum manubrium is effective for improving the stability of sternotomy closure.


Assuntos
Implantes Absorvíveis , Manúbrio/cirurgia , Esterno/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esternotomia
6.
J Stroke Cerebrovasc Dis ; 23(7): 1903-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24809672

RESUMO

BACKGROUND: In specific stroke cases, serial diffusion-weighted magnetic resonance imaging (DW MRI) on day 1 was unable to show a lesion, whereas that on day 4 and later clearly revealed a lesion. However, clinical features of this phenomenon ("invisible" brain stem infarction [IBI] at the first day) have not been fully delineated. METHODS: We retrospectively recruited 212 stroke patients in the Emergency Unit and Neurology Department. Among these, we studied patients with IBI. Definition of IBI is that acute and clear brain stem symptoms/signs on arrival were ameliorated at discharge and appearance of high signal intensity on serial DW images with low apparent diffusion coefficient (ADC) by 1.5 T MRI with 2-mm slices. RESULTS: IBI were found in only 6 patients. Day 1 invisible stroke was found only in the brain stem (17%, 6 of 35) but none (0 of 177) in the hemispheric infarction (P < .05). In most patients with IBI, DW MRI turned out visible at the third/fourth day. Before the fourth day, DW/ADC signal changes in patients with IBI were minimal. In IBI, lesion size (mean 2.7 mm(2)) was smaller than that of visible cases (mean 7.3 mm(2)). In IBI, lesion location was mostly at the dorsolateral medulla. In IBI, sensory disturbance was significantly more common (67%) than visible cases (24%; P < .05), whereas dysarthria was less common (0%; P < .01) than visible cases (66%; P < .01). CONCLUSIONS: It is likely that patients with smaller stroke volume, sensory disturbance, and medullary location are prone to develop IBI. When evaluating stroke using MRI criteria, recognition of IBI is important to start early management.


Assuntos
Infartos do Tronco Encefálico/patologia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Imagem de Difusão por Ressonância Magnética , Serviços Médicos de Emergência , Feminino , Humanos , Masculino , Bulbo/patologia , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/etiologia , Estudos Retrospectivos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/patologia
7.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 80(2): 166-174, 2024 Feb 20.
Artigo em Japonês | MEDLINE | ID: mdl-37926521

RESUMO

We have been developing protective equipment for portable radiography in neonatal intensive care units because the portable radiography's X-ray tube is in close proximity to the head of the nurse who is assisting the patient. Although our initial protective-equipment design was highly effective, there were some concerns that it obstructed the view of the patient and was difficult to handle. To overcome this problem, we have developed two new types of protective device: a narrow-type 0.13 mmPb device, 17 cm long and 45 cm wide (weight 200 g); and a wide type with a wider core material, 45 cm long and 25 cm wide (weight 300 g), both of which can be hung from the collimator cover of mobile X-ray equipment. The measured protective effectiveness was 80.6% at head height for the wide type and 76.8% for the narrow type. A survey of nurses regarding the new protective devices revealed no significant differences between the two types in terms of visibility and whether the devices would be an obstacle when assisting patients. The nurses preferred the wider type, which offered better protection. Radiological technologists also liked that both types were easy to handle because the irradiation field could be adjusted even after the device was fitted. Both types of the new protective device are thus expected to be useful in clinical practice in terms of their high protective effect and improved ease of handling.


Assuntos
Unidades de Terapia Intensiva Neonatal , Equipamentos de Proteção , Recém-Nascido , Humanos , Doses de Radiação , Radiografia , Raios X
8.
Magn Reson Med Sci ; 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38233192

RESUMO

PURPOSE: To evaluate the significant findings of hip periprosthetic joint infection (PJI) using metal-artifact-reduction (MAR) MRI and to compare the MRI results to other clinical markers. METHODS: The results of MRI, including two-dimensional fast-spin echo sequences with increased bandwidth and multi-acquisition variable-resonance image combination selective for hips with orthopedic implants at 1.5T (from April 2014 to November 2021), were retrospectively assessed for imaging findings and diagnostic impressions by two radiologists. Clinical data and courses were also investigated. Univariate and multivariate analyses were performed to identify the significant MRI findings in patients with hip PJI and those who underwent surgical intervention. The MRI impressions were compared with other clinical markers in diagnosing hip PJI. RESULTS: Thirty-seven hip joints in 24 Asian patients (age = 73.9 ± 10.8 years; 18 females) were included. Twelve hip joints (32%) had PJI; seven underwent a surgical intervention. The significant findings for hip PJI included periosteal edema of the acetabulum, intermuscular edema, intramuscular fluid collection, and lymphadenopathy (P < 0.05). In the cases with surgical intervention, the significant findings included capsular distension, capsular thickening, an osteolysis-like pattern of the femur, subcutaneous fluid collection, and lymphadenopathy (P < 0.05). The MRI impressions had high diagnostic significance for both hip PJI cases and those with surgical intervention (P < 0.001). The MRI impression was more significant for hip PJI than the other clinical markers (P < 0.05), while the other clinical markers were more significant in the cases with surgical intervention (P < 0.05). CONCLUSION: The significant findings in the hip PJI cases included acetabular periosteal edema, intermuscular edema, intramuscular fluid collection, and lymphadenopathy. The significant findings in the cases with surgical intervention included capsular distention, capsular thickening, a femoral osteolysis-like pattern, subcutaneous fluid collection, and lymphadenopathy. The utilization of MAR MRI demonstrated great diagnostic significance for hip PJI.

9.
Neuroradiology ; 55(5): 559-66, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23322456

RESUMO

INTRODUCTION: The purpose of this study was to identify brain atrophy specific for dementia with Lewy bodies (DLB) and to evaluate the discriminatory performance of this specific atrophy between DLB and Alzheimer's disease (AD). METHODS: We retrospectively reviewed 60 DLB and 30 AD patients who had undergone 3D T1-weighted MRI. We randomly divided the DLB patients into two equal groups (A and B). First, we obtained a target volume of interest (VOI) for DLB-specific atrophy using correlation analysis of the percentage rate of significant whole white matter (WM) atrophy calculated using the Voxel-based Specific Regional Analysis System for Alzheimer's Disease (VSRAD) based on statistical parametric mapping 8 (SPM8) plus diffeomorphic anatomic registration through exponentiated Lie algebra, with segmented WM images in group A. We then evaluated the usefulness of this target VOI for discriminating the remaining 30 DLB patients in group B from the 30 AD patients. Z score values in this target VOI obtained from VSRAD were used as the determinant in receiver operating characteristic (ROC) analysis. RESULTS: Specific target VOIs for DLB were determined in the right-side dominant dorsal midbrain, right-side dominant dorsal pons, and bilateral cerebellum. ROC analysis revealed that the target VOI limited to the midbrain exhibited the highest area under the ROC curves of 0.75. CONCLUSIONS: DLB patients showed specific atrophy in the midbrain, pons, and cerebellum. Midbrain atrophy demonstrated the highest power for discriminating DLB and AD. This approach may be useful for determining the contributions of DLB and AD pathologies to the dementia syndrome.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Imagem de Tensor de Difusão/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Doença por Corpos de Lewy/patologia , Técnica de Subtração , Idoso , Algoritmos , Interpretação Estatística de Dados , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Reconhecimento Automatizado de Padrão/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 79(4): 321-330, 2023 Apr 20.
Artigo em Japonês | MEDLINE | ID: mdl-36823093

RESUMO

Portable imaging in the NICU requires the assistance of a nurse, and the nurse is in close proximity to the X-ray tube, In all, 64 percent of our nurses thought that additional protective equipment was needed. Therefore, a radiation protection device was created and its usefulness was verified. A protective equipment of 0.13 mmPb with a width of 38 cm and a length of 70 cm was made and hung from the mono-tank X-ray unit of the mobile X-ray unit. The position of the nurse was set at 30 cm outward from the center of the irradiation field, and the protective effect was measured at three points: (a) the patient's height, (b) 30 cm above the patient, and (c) 60 cm above the patient. For the imaging conditions, a 2-liter plastic bottle filled with water was placed in the incubator, and measurements were taken with an SID of 100 cm, irradiated field of 20.3 cm×25.4 cm, tube voltage of 58 kV, and tube current-time product of 10 mAs, which was converted to the actual imaging condition of 1 mAs. Based on the results obtained, a questionnaire survey was conducted on nurses' thoughts for the protective equipment created for them. Only 3% reduction in height of (a) where no protective equipment is reached but (b) 50% and (c) 92%, respectively. In all, 82 percent of the nurses had a favorable impression of the new protective equipment. It is expected that the protective equipment designed to control lens dose and reduce anxiety of nurses will be useful.


Assuntos
Unidades de Terapia Intensiva Neonatal , Proteção Radiológica , Recém-Nascido , Humanos , Radiografia , Fluoroscopia , Doses de Radiação , Imagens de Fantasmas
11.
Cureus ; 15(12): e51384, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38292947

RESUMO

Objective This study aimed to investigate the correlation between enhanced inner ear magnetic resonance imaging (MRI) findings and vestibular and cochlear function test results in patients with definite Meniere's disease and confirmed endolymphatic hydrops. Methods Among 70 consecutive patients diagnosed with definite Meniere's disease, 49 underwent contrast-enhanced 3-T inner ear MRI. The patients also underwent pure-tone audiometry, glycerol, caloric, and vestibular-evoked myogenic potential (VEMP) tests. Correlations between the pure-tone audiometry, glycerol test, caloric test, VEMP test, and MRI findings were evaluated using the chi-square test or Fisher's exact test, Student's t-test, one-way ANOVA, and Bonferroni's post-hoc test. Results Contrast-enhanced inner ear MRI revealed that 33 of 49 patients (67.3%) had endolymphatic hydrops. Among them, 19 patients had bilateral endolymphatic hydrops, and 14 had unilateral hydrops. The mean hearing threshold was higher in patients with endolymphatic hydrops than those without (p< 0.001). The proportion of patients with positive glycerol test results was higher among those with endolymphatic hydrops than in those without (p= 0.01). The rate of abnormal caloric response in patients with and without endolymphatic hydrops was not significantly different (p= 0.09). Furthermore, the rate of abnormal VEMP response in patients with and without endolymphatic hydrops was not significantly different (p= 0.70). On the affected side, in the caloric test, the ratio of the presence of vestibular and cochlear hydrops was similar (p= 1.00). On the affected side, in the VEMP test, the ratio of the presence of vestibular and cochlear hydrops was also similar (p= 0.80). The consistency of the caloric test in detecting cochlear hydrops was higher than that of the VEMP test (p= 0.04). The consistency of the caloric test in detecting vestibular hydrops tended to be higher (but not significantly) than that of the VEMP test (p= 0.11). Conclusion The cochlea and vestibule on the clinically affected side were more likely to have endolymphatic hydrops revealed by contrast-enhanced 3-T inner ear MRI than on the unaffected side. The sum of the three low frequencies (125, 250, and 500 Hz) of the pure-tone audiometry was higher in patients with endolymphatic hydrops than in those without endolymphatic hydrops. The caloric test was more consistent in detecting endolymphatic hydrops, especially cochlear hydrops, than the VEMP test in patients with definite Meniere's disease. The results of this study may contribute to the future diagnosis of Meniere's disease and improve the understanding of endolymphatic hydrops.

12.
J Magn Reson Imaging ; 35(1): 174-80, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21960437

RESUMO

PURPOSE: To examine metabolic changes of the brain in early infancy measured by the LCModel with the water scaling method (LCModel-WS), and to determine whether the unsuppressed water signal (UWS) on the MR console and the area of the unsuppressed water peak (AUW) in the LCModel can be used to correct metabolite concentrations. MATERIALS AND METHODS: MR spectroscopy was performed on a 1.5 Tesla MR scanner. To determine whether UWS and AUW increases linearly with PD and exp(-TE/T2), these values were measured using three phantoms with different PD and T2 values. UWS and AUW were also measured (PRESS, TR = 5000 ms, TE = 30 ms, VOI = 4.5 mL) in 57 pediatric controls (aged 2 weeks to 15 years). RESULTS: Phantom studies revealed UWS and AUW increases linearly with PD and exp(-TE/T2). UWS and AUW were high in controls younger than 2 years of age, but gradually decreased to become almost constant after 4 years (UWS = 504 × 10(3) , AUW = 2.05 × 10(7)). AUW was linearly proportional to UWS in controls. These indicated that metabolite concentrations should be multiplied by the ratio of UWS/504 × 10(3) or AUW/2.05 × 10(7). Age dependent metabolite concentrations corrected by the ratio were obtained. CONCLUSION: Both UWS and AUW can be used to correct metabolite concentrations; these corrections can significantly improve quantification of metabolites' concentration in early childhood.


Assuntos
Encéfalo/patologia , Espectroscopia de Ressonância Magnética/métodos , Adolescente , Criança , Pré-Escolar , Análise de Fourier , Humanos , Processamento de Imagem Assistida por Computador/métodos , Lactente , Recém-Nascido , Imagens de Fantasmas , Prótons , Reprodutibilidade dos Testes , Água/química
13.
Neurourol Urodyn ; 31(1): 50-5, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22038765

RESUMO

OBJECTIVES: To elucidate the pathophysiology of urinary dysfunction in idiopathic normal-pressure hydrocephalus (iNPH) by single-photon emission computed tomography (SPECT) and statistical brain mapping. METHODS: Urinary symptoms were observed and N-isopropyl-p-[(123)I]-iodoamphetamine (IMP)-SPECT imaging was performed in 97 patients with clinico-radiologically definite iNPH. The patients included 56 men and 41 women; mean age, 74 years. The statistical difference in normalized mean tracer counts was calculated and visualized between patients with urinary dysfunction of severer degrees (>grade 2/4) and milder degrees (

Assuntos
Lobo Frontal/irrigação sanguínea , Lobo Frontal/diagnóstico por imagem , Hidrocefalia de Pressão Normal/complicações , Fluxo Sanguíneo Regional/fisiologia , Incontinência Urinária/epidemiologia , Transtornos Urinários/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Mapeamento Encefálico , Transtornos Cognitivos/fisiopatologia , Feminino , Lobo Frontal/fisiopatologia , Transtornos Neurológicos da Marcha/fisiopatologia , Humanos , Hidrocefalia de Pressão Normal/fisiopatologia , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Tomografia Computadorizada de Emissão de Fóton Único , Incontinência Urinária/fisiopatologia , Transtornos Urinários/fisiopatologia
16.
Artigo em Japonês | MEDLINE | ID: mdl-35185096

RESUMO

The bone mineral density (BMD) measurement of the lumbar spine with dual-energy X-ray absorptiometry (DXA) has the advantage of being able to detect early changes in BMD, which is usually used for the evaluation of drug therapy. However, DXA is not considered suitable for spinal deformity because it is a two-dimensional measurement. The aims of this study were to compare frontal and lateral measurements with a phantom and to examine the possibility of the evaluation of lumbar spine BMD in spinal deformity. The values of frontal and lateral measurements were compared when the lumbar phantom was tilted by 10 degrees from 0 to 40 degrees, assuming kyphosis, and when it was tilted by 5 degrees from 0 to 10 degrees to the right and left, assuming scoliosis. We revealed that in the case of kyphosis, the frontal is more accurate, and in the case of scoliosis, the lateral is more accurate; small rotation of subjects on the plane parallel to the image receiving surface could be acceptable. In general, the two-directional BMD measurement is useful for the improvement of the accuracy and may have a potential to measure patients with spinal deformity, which was previously thought to be impossible.


Assuntos
Densidade Óssea , Escoliose , Absorciometria de Fóton/métodos , Humanos , Vértebras Lombares/diagnóstico por imagem , Imagens de Fantasmas
17.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 78(12): 1425-1435, 2022 Dec 20.
Artigo em Japonês | MEDLINE | ID: mdl-36351610

RESUMO

Lowering the dose limit for the lens of the eye incorporated into the Regulation on Prevention of Ionizing Radiation Hazards, effective on April 2021, and dose reduction will become more and more important in the field of radiation. Radiation protective cloth is used as a protective equipment in fluoroscopy rooms. Although it is usually used to protect staff from radiation exposure during endoscopic retrograde cholangiopancreatography, we investigated whether there is a way to use it for procedures in clean areas. Assuming ureterostomy fistula replacement in urology, the protective cloth was suspended on the side of the patient's head and posterior aspect of the tube, and the distance between the anterior aspect of the X-ray tube and the patient's foot was 55 cm. As a result of measuring the dose rate, a 10% dose reduction was obtained for the lens of the eye of the surgeon, and the distribution of air dose rate in the examination room was significantly reduced. Although scattered radiation from the radiation protection cloth appeared in some areas, the radiation dose to the patient was reduced throughout the body, and a high degree of radiation protection was obtained, especially for the lens of the eye. It is expected that the radiation protection cloths may be useful even when the length of the cloths is limited due to the cleanliness of the area.


Assuntos
Cristalino , Exposição Ocupacional , Exposição à Radiação , Proteção Radiológica , Humanos , Doses de Radiação , Fluoroscopia , Exposição Ocupacional/prevenção & controle
18.
J Artif Organs ; 14(1): 39-42, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21229278

RESUMO

Life expectancy of the chronic dialysis patients depends upon the underlying renal disease, but its influence on the outcome of heart valve replacement has not been studied. We aimed to elucidate the difference in the early and midterm results of heart valve replacement according to the etiology of renal diseases. We retrospectively analyzed 17 patients on chronic dialysis who underwent heart valve replacement from 2002 to October 2009. Underlying renal disease was primary in ten patients (glomerulonephritis 8, others 2) and secondary in seven (nephrosclerosis 4, diabetic nephropathy 3). Mean age was 61 ± 10 for primary and 67 ± 7 for secondary renal diseases. Mean duration of dialysis was 18 ± 6 years for primary and 9 ± 9 for secondary renal diseases (p = 0.02). In the aortic position, mechanical valves were used in 12 patients and bioprostheses in three. In the mitral position, mechanical valves were used in all four. Deep hypothermic operation was required for severe aortic calcification in five (primary 5). Mean follow up period was 23 ± 18 months. There were two in-hospital deaths in patients with primary renal disease. Three-year survival rate including hospital deaths, on the other hand, was higher for primary renal diseases (80%) than secondary ones (34%). Despite elevated perioperative risk due to consequence of longer duration of dialysis, midterm survival of patients with primary renal diseases seemed better than for those with secondary renal diseases. These results may help the choice of heart valve prosthesis in chronic dialysis patients.


Assuntos
Bioprótese , Doenças das Valvas Cardíacas/cirurgia , Próteses Valvulares Cardíacas , Valvas Cardíacas/cirurgia , Falência Renal Crônica/etiologia , Falência Renal Crônica/terapia , Diálise Renal , Idoso , Análise de Variância , Feminino , Doenças das Valvas Cardíacas/mortalidade , Implante de Prótese de Valva Cardíaca , Humanos , Falência Renal Crônica/mortalidade , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida , Resultado do Tratamento
19.
Cardiovasc Intervent Radiol ; 44(6): 988-991, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33709280

RESUMO

A 54-year-old male with liver cirrhosis (Child-Pugh score 5) presented with severe hepatogenous diabetes (HbA1c 12.6%). Contrast-enhanced CT showed a large portosystemic shunt from the inferior mesenteric vein to the left internal iliac vein. Glucose monitoring showed postprandial hyperglycemia and reactive hypoglycemia. After balloon-occluded retrograde transvenous obliteration (BRTO) and partial splenic transarterial embolization, postprandial hyperglycemia was diminished. Seven months later, HbA1c had improved from 12.6% to 6.7%. In this case, postprandial hyperglycemia occurred by direct delivery of glucose into the systemic circulation via the shunt, and fasting hypoglycemia occurred during treatment with oral antidiabetic agents and insufficient gluconeogenesis. BRTO of the portosystemic shunt resulted in improvement in hepatogenous diabetes.


Assuntos
Fístula Arteriovenosa/complicações , Fístula Arteriovenosa/terapia , Oclusão com Balão/métodos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Embolização Terapêutica/métodos , Cirrose Hepática/complicações , Humanos , Veia Ilíaca/anormalidades , Masculino , Veias Mesentéricas/anormalidades , Pessoa de Meia-Idade , Resultado do Tratamento
20.
Jpn J Radiol ; 39(11): 1023-1038, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34125369

RESUMO

With the advent of antiretroviral therapy (ART), the prognosis of people infected with human immunodeficiency virus (HIV) has improved, and the frequency of HIV-related central nervous system (CNS) diseases has decreased. Nevertheless, mortality from HIV-related CNS diseases, including those associated with ART (e.g., immune reconstitution inflammatory syndrome) remains significant. Magnetic resonance imaging (MRI) can improve the outlook for people with HIV through early diagnosis and prompt treatment. For example, HIV encephalopathy shows a diffuse bilateral pattern, whereas progressive multifocal leukoencephalopathy, HIV-related primary CNS lymphoma, and CNS toxoplasmosis show focal patterns on MRI. Among the other diseases caused by opportunistic infections, CNS cryptococcosis and CNS tuberculosis have extremely poor prognoses unless diagnosed early. Immune reconstitution inflammatory syndrome shows distinct MRI findings from the offending opportunistic infections. Although distinguishing between HIV-related CNS diseases based on imaging alone is difficult, in this review, we discuss how pattern recognition approaches can contribute to their early differentiation.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS , Doenças do Sistema Nervoso Central , Infecções por HIV , Sistema Nervoso Central , Infecções por HIV/complicações , Infecções por HIV/diagnóstico por imagem , Infecções por HIV/tratamento farmacológico , Humanos , Imageamento por Ressonância Magnética
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