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1.
J Comput Assist Tomogr ; 48(2): 194-199, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37965744

RESUMO

OBJECTIVES: To investigate the relationship between conventionally obtained serum-based biochemical indices and intravoxel incoherent motion imaging (IVIM) parameters compared with magnetic resonance elastography (MRE). METHODS: Patients with hepatocellular carcinoma who underwent ≥2 liver magnetic resonance imaging (MRI) scan, including IVIM and MRE, between 2017 and 2020 and biochemical testing within 1 week before or after MRI were included in this study. Biochemical tests were performed to determine the albumin-bilirubin (ALBI) score and modified ALBI (mALBI) grade, aspartate aminotransferase to platelet ratio index (APRI), and fibrosis-4 index (FIB-4). The diffusion coefficient ( D ), pseudo-diffusion coefficient ( D *), fractional volume occupied by flowing spins ( f ), and apparent diffusion coefficient were calculated for IVIM. The correlations between (1) the imaging parameters and biochemical indices and (2) the changes in mALBI grades and imaging parameters were evaluated. RESULTS: This study included 98 scans of 40 patients (31 men; mean age, 67.7 years). The correlation analysis between the biochemical and IVIM parameters showed that ALBI score and D* had the best correlation ( r = -0.3731, P < 0.001), and the correlation was higher than that with MRE ( r = 0.3289, P < 0.001). However, among FIB-4, APRI, and MRI parameters, MRE outperformed IVIM parameters (MRE and FIB-4, r = 0.3775, P < 0.001; MRE and APRI, r = 0.4687, P < 0.001). There were significant differences in the changes in MRE among the 3 groups (improved, deteriorated, and unchanged mALBI groups) in the analysis of covariance ( P = 0.0434). There were no significant changes in IVIM. CONCLUSIONS: Intravoxel incoherent motion imaging has the potential to develop into a more readily obtainable method of liver function assessment.


Assuntos
Carcinoma Hepatocelular , Técnicas de Imagem por Elasticidade , Neoplasias Hepáticas , Masculino , Humanos , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Técnicas de Imagem por Elasticidade/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Movimento (Física)
2.
Skeletal Radiol ; 52(7): 1349-1358, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36609720

RESUMO

OBJECTIVE: To confirm the relationship between lumbar spinal stenosis (LSS) and cauda equina movement during the Valsalva maneuver. MATERIALS AND METHODS: Two radiologists at our institution independently evaluated cauda equina movement on pelvic cine MRI, which was performed for urethrorrhea after prostatectomy or pelvic prolapse in 105 patients (99 males; mean age: 69.0 [range: 50-78] years), who also underwent abdominopelvic CT within 2 years before or after the MRI. The qualitative assessment of the cine MRI involved subjective determination of the cauda equina movement type (non-movement, flutter, and inchworm-manner). The severity of LSS on abdominopelvic CT was quantified using our LSS scoring system and performed between L1/2 and L5/S1. We calculated the average LSS scores of two analysts and extracted the worst scores among all levels. RESULTS: Cauda equina movement was observed in 15 patients (14%), inchworm-manner in 10 patients, and flutter in five patients. Participants with cauda equina movement demonstrated significantly higher LSS scores than those without movement (P < 0.001, Wilcoxon's rank-sum test). A significant difference was observed in the worst LSS scores between participants without movement and those with inchworm-manner movement (P < 0.001, Bonferroni's corrected). There were no significant differences between participants without movement and those with flutter movement (P = 0.3156) and between participants with flutter movement and those with inchworm-manner movement (P = 0.4843). CONCLUSION: Cauda equina movement in cine MRI during the Valsalva maneuver is occasionally observed in patients with severe LSS, and may be associated with pathogenesis of redundant nerve roots.


Assuntos
Cauda Equina , Estenose Espinal , Masculino , Humanos , Idoso , Cauda Equina/diagnóstico por imagem , Cauda Equina/patologia , Cauda Equina/cirurgia , Estenose Espinal/complicações , Manobra de Valsalva , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética
3.
Acta Neurochir (Wien) ; 165(8): 2111-2120, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37341825

RESUMO

BACKGROUND: Previous studies have shown that the Valsalva maneuver (VM) causes spinal canal object movements. We hypothesized that this occurs because of cerebrospinal fluid (CSF) flow generated from intradural space reduction. Previous studies using myelograms reported lumbar CSF space changes during inspiration. However, no similar studies have been conducted using modern MRI. Therefore, this study analyzed intradural space reduction during the VM using cine magnetic resonance imaging (MRI). METHODS: The participant was a 39-year-old, healthy, male volunteer. Cine MRI involved fast imaging employing steady-state acquisition cine sequence during three resting and VM sets for 60 s each. The axial plane was at the intervertebral disc and vertebral body levels between Th12 and S1 during cine MRI. This examination was performed on 3 separate days; hence, data from nine resting and VM sets were available. Additionally, two-dimensional myelography was performed during rest and the VM. RESULTS: Intradural space reduction was observed during the VM using cine MRI and myelography. The intradural space cross-sectional area during the VM (mean: 129.3 mm2; standard deviation [SD]: 27.4 mm2) was significantly lower than that during the resting period (mean: 169.8; SD: 24.8; Wilcoxon signed-rank test, P < 0.001). The reduction rate of the vertebral body level (mean: 26.7%; SD: 9.4%) was larger than that of the disc level (mean: 21.4%; SD: 9.5%; Wilcoxon rank sum test, P = 0.0014). Furthermore, the reduction was mainly observed on the ventral and bilateral intervertebral foramina sides at the vertebral body and intervertebral disc levels, respectively. CONCLUSION: The intradural space was reduced during the VM, possibly because of venous dilatation. This phenomenon may be associated with CSF flow, intradural object movement, and nerve compression, potentially leading to back pain.


Assuntos
Deslocamento do Disco Intervertebral , Imagem Cinética por Ressonância Magnética , Humanos , Masculino , Adulto , Mielografia , Manobra de Valsalva , Imageamento por Ressonância Magnética/métodos , Canal Medular , Deslocamento do Disco Intervertebral/patologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia
4.
Artigo em Japonês | MEDLINE | ID: mdl-29353832

RESUMO

The aim of this study was to evaluate the measurement precision and accuracy of T1 mapping using a polarity corrected (PC) TI prep tool, which was based on fast field echo (FFE) and obtained one data point with one inversion recovery (IR) pulse. A phantom was used consisting of eight materials with different Gd concentrations. T1 mappings were measured by changing the trigger interval and the inversion time (TI) interval. The T1 mapping measurement precision using the PC TI prep tool increased as the trigger interval was made longer. The measurement precision didn't depend on the interval of TI. On the other hand, when the trigger intervals are more than 1000 ms, the measurement accuracy was less than approximately 8%. By setting the optimal end of TI, the T1 mapping using a PC TI prep tool could measure the T1 value precisely and accurately.


Assuntos
Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas , Reprodutibilidade dos Testes
5.
Fukushima J Med Sci ; 68(2): 135-141, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35979579

RESUMO

Lumbar spinal canal stenosis (LSS) is a common spinal disorder among older people. Some LSS patients say that their pain worsens when they lift heavy objects. The Valsalva maneuver is the optimal breathing pattern for producing maximal force. Herein, we present two cases of LSS where the movement of the cauda equina was observed during the Valsalva maneuver.Case Summary:Case 1: A 74-year-old female with a history of LSS presented to our Department of Urology with frequent urination. The patient was diagnosed as having uterine and bladder prolapse. Pelvic cine MRI scan was conducted for detailed evaluation. While the Valsalva maneuver was performed to diagnose pelvic organ prolapses, we observed movement of the cauda equina. Spine MRI and CT, performed one year before presentation, showed severe LSS due to degenerative spondylolisthesis.Case 2: A 73-year-old male underwent radical prostatectomy for prostate cancer. A follow-up cine MRI to confirm urethrorrhea showed the cauda equina moving during the Valsalva maneuver. Moderate LSS due to degenerative spondylolisthesis was retrospectively found on abdominal CT performed before prostatectomy.Conclusion: The findings of our report suggest that movement of the cauda equina during the Valsalva maneuver may be implicated in LSS.


Assuntos
Cauda Equina , Estenose Espinal , Espondilolistese , Idoso , Cauda Equina/cirurgia , Constrição Patológica , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Masculino , Estudos Retrospectivos , Canal Medular , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/cirurgia , Manobra de Valsalva
6.
Radiol Phys Technol ; 14(1): 50-56, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33387358

RESUMO

Myocardial T1 mapping is a useful technique for the diagnosis of diffuse fibrosis. Although modified look-locker inversion recovery is a widely used T1 mapping method, variation in T1 values has been reported. Non-uniform T1 maps may hinder differentiation between healthy and diseased myocardial tissue. The purpose of this study was to investigate the uniformity of T1 mapping using polarity corrected inversion time preparation (PC TI prep) in a myocardial phantom and healthy volunteers. The myocardial phantom was scanned between polyvinyl alcohol (PVA) and air. T1 values were measured using inversion recovery fast spin-echo (IR-FSE) and PC TI prep in areas adjacent to PVA and air. For the volunteer study, the short-axis plane was imaged using the PC TI prep to compare T1 values in the myocardium of the septal and lateral walls. The T1 value of the phantom using the IR-FSE was not significantly different in the area between PVA and air, whereas the T1 value using the PC TI prep in the air area was significantly lower than that in the PVA area. T1 mapping of the healthy myocardium exhibited no significant difference between the septal and lateral walls. The T1 value using the PC TI prep in the air area was 6.3% lower than that using IR-FSE. In this study, T1 mapping using the PC TI prep exhibited high uniformity of T1 values.


Assuntos
Imageamento por Ressonância Magnética , Miocárdio , Voluntários Saudáveis , Humanos , Imagens de Fantasmas , Reprodutibilidade dos Testes
7.
Reprod Biomed Online ; 18(5): 635-43, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19549441

RESUMO

Despite polycystic ovaries (PCO) being a common morphology in women with polycystic ovary syndrome and regular menstruation, the regulatory principles in the morphogenesis of antral follicles have not yet been elucidated. In recognition of the complementary interaction between androgen-induced expression of the FSH receptor and FSH-augmented expression of the androgen receptor in granulose cells of antral follicles, a possible correlation of antral follicle count (AFC) and pituitary-ovarian androgenic function was investigated in 180 infertile women over days 3-5 of the menstrual cycle. Six discrete types of PCO with decreasing pituitary-ovarian androgenic function were identified: Type I (classical Stein-Leventhal syndrome), Type II (hyperandrogenemism), Type III (singular hyper-LH), Type IV (cryptic hyperandrogenism), Type V (relative LH dominancy) and Type VI (relative FSH dominancy), in parallel to a diminishing number of AFC from Type I to Type VI. Because during the early follicular phase of the cycle until the selection of the dominant follicle, antral follicles are composed of newly emerged healthy follicles plus atretic antral follicles that remain non-ovulated from previous cycles, it is proposed that the six types of PCO may represent the folliculogenetic spectra along which PCO morphogenesis proceeds.


Assuntos
Morfogênese/fisiologia , Ovário/crescimento & desenvolvimento , Síndrome do Ovário Policístico/classificação , Síndrome do Ovário Policístico/patologia , Adulto , Feminino , Gonadotropinas Hipofisárias/sangue , Humanos , Imunoensaio , Infertilidade Feminina/etiologia , Ovário/patologia , Síndrome do Ovário Policístico/complicações , Estatísticas não Paramétricas , Testosterona/sangue
8.
Artigo em Inglês | MEDLINE | ID: mdl-14970784

RESUMO

OBJECTIVE: The objective of the study was to examine the morphological changes of neural elements in dentin-pulp complex ultrastructurally after Er:YAG laser irradiation and elucidate the mechanism of pain reduction in cavity ablation. STUDY DESIGN: The Er:YAG laser was applied at occlusal surfaces of upper and lower first molar cusps of 6 rats, and shallow cavities were ablated. The dentin and pulps were examined with light and electron microscopes at 6 hours after the irradiation. Teeth, without laser irradiation, from three rats were used as controls. RESULTS: Disruption of nerve terminals in the dentinal tubules, degeneration of nerve terminals between odontoblasts, and disruption of the myelin sheath in the pulp core were demonstrated with electron microscope. CONCLUSION: Some Er:YAG laser beams could penetrate to deeper areas than ablated area, and damage of nerve fibers and terminals might be a mechanism of pain reduction in cavity ablation with Er:YAG laser.


Assuntos
Polpa Dentária/efeitos da radiação , Dentina/efeitos da radiação , Lasers , Silicatos de Alumínio , Animais , Membrana Celular/efeitos da radiação , Membrana Celular/ultraestrutura , Polpa Dentária/inervação , Polpa Dentária/ultraestrutura , Dentina/inervação , Dentina/ultraestrutura , Érbio , Terapia a Laser , Microscopia Eletrônica , Bainha de Mielina/efeitos da radiação , Bainha de Mielina/ultraestrutura , Degeneração Neural/patologia , Terminações Nervosas/efeitos da radiação , Terminações Nervosas/ultraestrutura , Fibras Nervosas/efeitos da radiação , Fibras Nervosas/ultraestrutura , Odontoblastos/efeitos da radiação , Odontoblastos/ultraestrutura , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Coroa do Dente , Ítrio
9.
Artigo em Inglês | MEDLINE | ID: mdl-12193903

RESUMO

OBJECTIVE: Our objective was to compare the response of the monocyte/macrophage system of dental pulp to cavity preparation in aged rats (12 and 18 months old) with that seen in young adult rats (3 and 6 months old). STUDY DESIGN: Cavities were prepared on the upper first molars, and the lower first molars served as intact controls. Specimens were collected at 1 day after cavity preparation, and cryostat sections were made. RESULTS: Accumulation of OX6+ antigen-presenting cells along the pulp-dentin border and a marked increase in cell size ED2+ resident macrophages were noted in both young adult and aged rats after cavity preparation. In both cases, the number of ED1+ cells increased significantly after cavity preparation because of infiltrating monocytes. CONCLUSION: These findings suggest that the pulpal defense reaction of the monocyte/macrophage system to cavity preparation in aged rats does not differ markedly from that in young adult rats.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Preparo da Cavidade Dentária , Polpa Dentária/imunologia , Fatores Etários , Análise de Variância , Animais , Antígenos de Histocompatibilidade Classe II/biossíntese , Imuno-Histoquímica , Ativação de Macrófagos , Masculino , Dente Molar , Monócitos/imunologia , Monócitos/metabolismo , Ratos , Ratos Endogâmicos F344 , Estatísticas não Paramétricas
10.
Am J Reprod Immunol ; 58(4): 383-7, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17845209

RESUMO

PROBLEM: Recurrent spontaneous abortion (RSA) is defined by at least three consecutive abortions in otherwise healthy couples. Paternal lymphocyte alloimmunization therapy (PLAT) is an effective therapy for RSA in some cases, but there are no predictive markers about the effectiveness of PLAT. METHOD OF STUDY: Forty-two consecutive cases with primary RSA treated by PLAT and 23 controls were the subjects. Polymorphisms of human leukocyte antigen (HLA)-E, HLA-G, HLA-A, HLA-B, HLA-C and HLA-DRB1 were investigated by sequenced based typing. Promoter polymorphism and a 14 bp ins/del polymorphism in exon 8 were also investigated for HLA-G. RESULTS: Thirty-eight RSA wives became pregnant within 1 year after PLAT. Among them, 27 obtained babies (succeeded PLAT cases), while 11 again aborted with no detectable chromosomal abnormalities in the aborted fetuses (aborted PLAT cases). The frequencies of HLA-G*010401, A*2402, B*5201, and DRB1*1502 were significantly increased in the aborted cases than those in the succeeded cases or controls. Of note, HLA-G*010401 was found in all aborted cases whereas it was found in 51.9% of succeeded cases (odds ratio = 21.4, P = 0.006, P(c) = 0.03), and the presence of HLA-G*010401 could predict the abortion after PLAT with sensitivity and specificity of 100% and 48.1%, respectively. CONCLUSION: Human leukocyte antigen testing may be useful for predicting effectiveness of PLAT in RSA.


Assuntos
Aborto Habitual/terapia , Antígenos HLA/genética , Antígenos de Histocompatibilidade Classe I/genética , Transfusão de Linfócitos , Polimorfismo Genético , Aborto Habitual/genética , Aborto Habitual/imunologia , Feminino , Frequência do Gene , Predisposição Genética para Doença , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígenos HLA-C/genética , Antígenos HLA-DR/genética , Cadeias HLA-DRB1 , Antígenos HLA-G , Haplótipos , Humanos , Nascido Vivo , Seleção de Pacientes , Gravidez , Resultado do Tratamento
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