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1.
Cancer Imaging ; 22(1): 26, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672838

RESUMO

BACKGROUND: The assessment of metastatic breast cancer (MBC) can be limited with routine imaging such as computed tomography (CT) especially in bone-only or bone-predominant disease. This analysis investigates the effects of the use of WBMRI in addition to the use of routine CT, bone scintigraphy (BS) and fluorine-18-fluorodeoxyglucose positron emission tomography with computed tomography (FDG-PET/CT) on influencing systemic anti-cancer treatment (SACT) decisions in patients with known MBC. METHODS: MBC patients undergoing SACT who had WBMRI undertaken within 8 weeks of either a routine CT, BS or FDG-PET/CT were reviewed retrospectively. The clinical indications for undertaking the WBMRI examinations were recorded. Data on the extent and distribution of the disease were collected and discordance/concordance of disease status across the imaging modalities were compared. SACT decisions at each time point were also evaluated. RESULTS: There were 105 MBC patients with 148 WBMRI studies paired with CT, BS or FDG-PET/CT. 50 pairs (33.8%) showed differences in the extent of disease, with 44 pairs due to additional sites (AS) reported on WBMRI alone. 81 patients (Group 1) had one WBMRI paired with routine imaging due to a variety of indications, with clinical symptoms (such as bone pain) being the most common (24.7%). 24 patients (Group 2) had more than one WBMRI study paired with routine imaging comprising 67 pairs. 13/67 pairs (19.4%) showed discordance in assessments. 10/13 pairs had progressive disease (PD) reported on WBMRI alone. SACT change due to AS reported on WBMRI alone occurred in 21/23 pairs (91.3%) in Group 1. SACT change due to PD reported on WBMRI alone in Group 2 occurred in 6/14 pairs (42.9%). SACT change due to AS/PD in both groups occurred in 11/102 pairs (10.8%) with known invasive ductal carcinoma (IDC) and 13/28 pairs (46.4%) with invasive lobular carcinoma (ILC). CONCLUSIONS: The use of WBMRI in MBC led to earlier recognition of PD and SACT change compared with the other imaging modalities. A higher proportion of discordant response assessments and SACT changes were observed in ILC compared with IDC in our patient group, although larger-scale studies are required to investigate this further.


Assuntos
Neoplasias da Mama , Fluordesoxiglucose F18 , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons/métodos , Estudos Retrospectivos , Imagem Corporal Total/métodos
2.
Eur J Radiol ; 153: 110365, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35617871

RESUMO

OBJECTIVE: To describe the appearances of bone marrow in the appendicular skeleton on fat-suppressed T2-weighted sequences as assessed by whole-body MRI in healthy and asymptomatic children and adolescents. MATERIAL AND METHODS: Following ethical approval, we assessed the bone marrow of the extremities on water-only Dixon T2-weighted images as part of a whole-body MRI in 196 healthy and asymptomatic children aged 5-19 years. Based on a newly devised and validated scoring system, we graded intensity (0-2 scale) and extension (1-4 scale) of focal high signal bone marrow areas, and divided them into minor or major findings, based on intensity and extension, reflecting their potential conspicuousness in a clinical setting. RESULTS: In the upper extremity, we registered 366 areas with increased signal whereof 79 were major findings. In the lower extremities there were 675 areas of increased signal of which 340 were major findings. Hundred-and-fifteen (58.79%) individuals had at least one major finding, mainly located in the hand and proximal humerus, and the feet and knees. We found no differences according to gender, reported hours of sports activity, handedness, or age group, except for more minor findings in the upper extremities amongst 15-18-year-olds as compared to those aged 5-8 years. CONCLUSION: Focal areas of high signal intensity on whole-body MRI, T2-weighted fat suppressed images that, in a clinical setting could cause concern, were seen in more than half of healthy, asymptomatic children and adolescents. Awareness of this is important when interpreting whole-body MRI in this age group, particularly in the assessment of clinically silent lesions.


Assuntos
Imageamento por Ressonância Magnética , Imagem Corporal Total , Adolescente , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Criança , , Humanos , Úmero , Imageamento por Ressonância Magnética/métodos
3.
Nat Biomed Eng ; 6(5): 495-496, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35624149
4.
Eur J Nucl Med Mol Imaging ; 49(8): 2994-3004, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35567627

RESUMO

INTRODUCTION: Distinct physiological states arise from complex interactions among the various organs present in the human body. PET is a non-invasive modality with numerous successful applications in oncology, neurology, and cardiology. However, while PET imaging has been applied extensively in detecting focal lesions or diseases, its potential in detecting systemic abnormalities is seldom explored, mostly because total-body imaging was not possible until recently. METHODS: In this context, the present study proposes a framework capable of constructing an individual metabolic abnormality network using a subject's whole-body 18F-FDG SUV image and a normal control database. The developed framework was evaluated in the patients with lung cancer, the one discharged after suffering from Covid-19 disease, and the one that had gastrointestinal bleeding with the underlying cause unknown. RESULTS: The framework could successfully capture the deviation of these patients from healthy subjects at the level of both system and organ. The strength of the altered network edges revealed the abnormal metabolic connection between organs. The overall deviation of the network nodes was observed to be highly correlated to the organ SUV measures. Therefore, the molecular connectivity of glucose metabolism was characterized at a single subject level. CONCLUSION: The proposed framework represents a significant step toward the use of PET imaging for identifying metabolic dysfunction from a systemic perspective. A better understanding of the underlying biological mechanisms and the physiological interpretation of the interregional connections identified in the present study warrant further research.


Assuntos
COVID-19 , Neoplasias Pulmonares , Fluordesoxiglucose F18 , Humanos , Neoplasias Pulmonares/patologia , Tomografia por Emissão de Pósitrons/métodos , Imagem Corporal Total
5.
Eur J Nucl Med Mol Imaging ; 49(8): 2504-2513, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35578037

RESUMO

PURPOSE: The aim of this study is to explore the diagnostic value of the images obtained in ultrafast 30-s acquisition time by the total-body PET/CT (18F-FDG injection dose of about 3.7 MBq/kg), and to evaluate whether they can meet the requirements of clinical diagnosis or not. METHODS: This retrospective study explored the clinical value of ultrafast 30-s 18F-FDG total-body PET/CT in 88 oncology patients, using the post-surgical pathological diagnosis as the reference standard. The data were acquired over 300 s and reconstructed using all 300-s data (G300) and only the initial 30 s (G30). Two readers independently assessed all images qualitatively and quantitatively. The diagnostic performance was compared between G300 and G30. RESULTS: The G300 average qualitative score was higher than G30 (P < 0.001). G300 and G30 also differed quantitatively in the liver and mediastinum SUVmax, SD, and SNR (all P < 0.001), but had similar sensitivities (89.09% vs. 86.36%, P = 0.250). The G300 group had higher accuracy (79.73%) and a larger area under the curve (0.709) than G30 (77.70% and 0.695, respectively; all P > 0.05). CONCLUSION: The 30-s total-body PET/CT could meet clinical diagnostic requirements for malignant tumors in patients intolerant to prolonged horizontal positioning.


Assuntos
Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Humanos , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons/métodos , Estudos Retrospectivos , Imagem Corporal Total
6.
J Coll Physicians Surg Pak ; 32(4): S64-S66, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35633016

RESUMO

Synovitis, acne, pustulosis, hyperostosis, and osteomyelitis (SAPHO) syndrome is rare disease of unknown pathogenesis. Its diagnosis and treatment are difficult. There is no standardised treatment for SAPHO syndrome, and the results of empirical therapy are unpredictable. The whole-body bone scan may help evaluate the efficacy of SAPHO syndrome treatment. The case of a 52-year Chinese male, affected by SAPHO syndrome, is presented and discussed in this report. After the patient received methotrexate, prednisone and non-steroidal anti-inflammatory drugs (NSAIDs) for six months, his clinical symptoms and whole body bone scan signs improved. Key Words: SAPHO syndrome, Whole-body bone scintigraphy, Treatment efficacy.


Assuntos
Síndrome de Hiperostose Adquirida , Osteomielite , Síndrome de Hiperostose Adquirida/diagnóstico por imagem , Síndrome de Hiperostose Adquirida/tratamento farmacológico , Osso e Ossos , Humanos , Masculino , Osteomielite/diagnóstico por imagem , Osteomielite/tratamento farmacológico , Cintilografia , Imagem Corporal Total
7.
Nutrients ; 14(7)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35406138

RESUMO

The historical 1975 Reference Man is a 'model' that had been used as a basis for the calculation of radiation doses, metabolism, pharmacokinetics, sizes for organ transplantation and ergonomic optimizations in the industry, e.g., to plan dimensions of seats and other formats. The 1975 Reference Man was not an average individual of a population; it was based on the multiple characteristics of body compositions that at that time were available, i.e., mainly from autopsy data. Faced with recent technological advances, new mathematical models and socio-demographic changes within populations characterized by an increase in elderly and overweight subjects a timely 'state-of-the-art' 2021 Reference Body are needed. To perform this, in vivo human body composition data bases in Kiel, Baton Rouge, San Francisco and Honolulu were analyzed and detailed 2021 Reference Bodies, and they were built for both sexes and two age groups (≤40 yrs and >40 yrs) at BMIs of 20, 25, 30 and 40 kg/m2. We have taken an integrative approach to address 'structure-structure' and 'structure-function' relationships at the whole-body level using in depth body composition analyses as assessed by gold standard methods, i.e., whole body Magnetic Resonance Imaging (MRI) and the 4-compartment (4C-) model (based on deuterium dilution, dual-energy X-ray absorptiometry and body densitometry). In addition, data obtained by a three-dimensional optical scanner were used to assess body shape. The future applications of the 2021 Reference Body relate to mathematical modeling to address complex metabolic processes and pharmacokinetics using a multi-level/multi-scale approach defining health within the contexts of neurohumoral and metabolic control.


Assuntos
Tecido Adiposo , Imageamento por Ressonância Magnética , Absorciometria de Fóton/métodos , Adulto , Idoso , Composição Corporal , Água Corporal , Feminino , Humanos , Masculino , Imagem Corporal Total
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(2): 501-505, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35395986

RESUMO

OBJECTIVE: To explore the characteristics of ADC value changes in DWI of newly diagnosed symptomatic MM patients and its correlation with R-ISS stage. METHODS: The data of 148 newly diagnosed symptomatic MM patients treated by whole-body DWI scan at The First Affiliated Hospital of Soochow University from June 2016 to June 2019 were selected and retrospectively analyzed and 30 cases of age-matched healthy people were selected as controls. The differences of ADC values between the patients in normal control group, DWI- group and DWI+ group were compared, and the relationship between ADC values and R-ISS stage in MM patients was compared. RESULTS: The plasma cell percentage of the patients in DWI+ group was higher than those in DWI- group. ADC values of vertebra, sternum, rib, pectoral girdle, pelvic girdle of the patients in DWI+ group were significantly higher than those in DWI- group and normal control group. The ADC values of each part of the patients in DWI- group were higher than those in normal control group. ADC values of sternum, rib and pectoral girdle in the patients at R-ISS stage III were higher than those at R-ISS stage I and II, while, there was no statistical difference between R-ISS stage I and II groups. And there was no significant difference in ADC values of other bone parts such as vertebra and pelvic girdle in patients at R-ISS stage Ⅰ-Ⅲ. CONCLUSION: DWI+ in MM patients is related to higher tumor invasion. The ADC values of the DWI+ group are higher than those of the DWI- group; the bone ADC values of the DWI- patients are still higher than the normal ones. And there is a certain relationship between ADC value and R-ISS stage.


Assuntos
Doenças Ósseas , Mieloma Múltiplo , Imagem de Difusão por Ressonância Magnética , Humanos , Mieloma Múltiplo/diagnóstico por imagem , Estudos Retrospectivos , Imagem Corporal Total
9.
Pediatr Radiol ; 52(7): 1272-1282, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35445816

RESUMO

BACKGROUND: Whole-body magnetic resonance imaging (MRI) is increasingly being used in children, however, to date there are no studies addressing the reliability of the findings. OBJECTIVE: To examine intra- and interobserver reliability of a scoring system for assessment of high signal areas within the bone marrow, as visualized on T2-weighted, fat-saturated images. MATERIALS AND METHODS: Ninety-six whole-body MRIs (1.5 T) in 78 healthy volunteers (mean age: 11.5 years) and 18 children with chronic nonbacterial osteomyelitis (mean age: 12.4 years) were included. Coronal water-only Dixon T2-weighted images were used to score the left lower extremity/pelvis for high signal intensity areas, intensity (0-2 scale), extension (0-4 scale) and shape and contour in a blinded fashion by two pairs of radiologists. RESULTS: For the pelvis, grading of bone marrow signal showed moderate to good intra- and interobserver agreement with kappa values of 0.51-0.94 and 0.41-0.87, respectively. Corresponding figures for the femur were 0.61-0.68 within and 0.32-0.61 between observers, and for the tibia 0.60-0.72 and 0.51-0.73. Agreement for assessing extension was moderate to good both within and between observers for the pelvis (k = 0.52-0.85 and 0.35-0.80), for the femur (0.52-0.67 and 0.51-0.60) and for the tibia (k = 0.59-0.69 and 0.47-0.63) except for the femur metaphysis/diaphysis, with interobserver kappa values of 0.29-0.30. Scoring of shape was moderate to good within observers, but in general poorer between observers, with kappa values of 0.40-0.73 and 0.18-0.69, respectively. For contour, the corresponding figures were 0.35-0.62 and 0.09-0.54, respectively. CONCLUSION: MRI grading of intensity and extension of high signal intensity areas within the bone marrow of pelvis and lower limb performs well and thus can be used interchangeably by different observers, while assessment of shape and contour is reliable for the same observer but is less reliable between observers. This should be considered when performing clinical trials.


Assuntos
Medula Óssea , Imageamento por Ressonância Magnética , Medula Óssea/diagnóstico por imagem , Criança , Fêmur , Humanos , Imageamento por Ressonância Magnética/métodos , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Imagem Corporal Total
10.
Obesity (Silver Spring) ; 30(5): 1057-1065, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35384351

RESUMO

OBJECTIVE: Reliable and simple methods to quantify visceral adipose tissue (VAT) and VAT changes are needed. This study investigated the validity of dual-energy x-ray absorptiometry (DXA) compared with magnetic resonance imaging (MRI) for estimating VAT cross sectionally and longitudinally after surgery-induced weight loss in women with severe obesity. METHODS: Women with obesity (n = 36; mean age 43 [SD 10] years; 89% White) with DXA and MRI before bariatric surgery (T0) at 12 (T12) and 24 months (T24) post surgery were included. CoreScan (GE Healthcare, Chicago, Illinois) estimated VAT from 20% of the distance between the top of the iliac crest and the base of the skull. MRI VAT (total VAT) was measured from the base of the heart to the sacrum/coccyx on a whole-body scan. RESULTS: Mean DXA VAT was 45% of MRI VAT at T0, 46% at T12, and 68% at T24. DXA underestimated change in MRI VAT between T0 and T12 by 26.1% (0.81 kg, p = 0.03) and by 71.7% (0.43 kg, p < 0.001) between T12 and T24. The relationship between DXA VAT and MRI VAT differed between T12 and T24 (p value for interaction = 0.03). CONCLUSIONS: CoreScan lacks validity for comparing VAT across individuals or for estimating the size of changes within individuals; however, within the limits of measurement error, it may provide a useful indicator of whether some VAT change has occurred within an individual.


Assuntos
Gordura Intra-Abdominal , Obesidade Mórbida , Absorciometria de Fóton/métodos , Tecido Adiposo , Adulto , Feminino , Humanos , Gordura Intra-Abdominal/diagnóstico por imagem , Obesidade Mórbida/diagnóstico por imagem , Obesidade Mórbida/cirurgia , Perda de Peso , Imagem Corporal Total
11.
Clin Imaging ; 87: 1-4, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35439719

RESUMO

PURPOSE: To evaluate postoperative serum thyroglobulin (Tg) as a reliable tumor marker in low-risk differentiated thyroid cancer (DTC). METHODS: Two hundred and three patients met the selection criteria of >18 years old; who had undergone total or near total thyroidectomy; had a postoperative Tg, and had undergone 131I pre ablation whole body scan (PA-WBS). The primary endpoint was the correlation between Tg level and functional remnant thyroid tissues. Outcomes were categorized as concordant and discordant. Concordant results were positive Tg (>1 ng/ml) with positive PA-WBS or negative Tg (<1 ng/ml) with negative PA-WBS. Discordant results were negative Tg with a positive PA-WBS or positive Tg with a negative PA-WBS. To increase the sensitivity of Tg detection, we evaluated Tg in patients with high thyroid stimulating hormone (TSH) with serum level >30 mU/l on thyroxine withdrawal protocol. RESULTS: One hundred ten patients (54.1%) had discordant results (p < 0.05) with positive PA-WBS and Tg <1 ng/ml, while 93 patients (45.9%) had concordant results. For concordant results, 88 patients had positive PA-WBS and Tg >1 ng/ml, and 5 patients had negative PA-WBS and Tg <1 ng/ml. There was no patient with Tg >1 ng/ml and negative PA-WBS. There were 74 patients with high TSH (>30 mU/l) on abstention (thyroxine withdrawal protocol). Twenty-four (32.5%) had discordant results (p < 0.001) and 50 (67.5%) had concordant results. CONCLUSION: There is low correlation between postoperative Tg and PA-WBS. The sole use of Tg as a serum biomarker for postoperative disease status may not be reliable.


Assuntos
Adenocarcinoma , Tireoglobulina , Neoplasias da Glândula Tireoide , Humanos , Radioisótopos do Iodo/uso terapêutico , Cintilografia , Tireoglobulina/sangue , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Tireotropina , Tiroxina , Imagem Corporal Total
12.
Nucl Med Commun ; 43(6): 663-668, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35363221

RESUMO

AIM: The aim of this study was to evaluate the incidence of positive WBS in patients with negative stimulated thyroglobulin (sTg), to define the clinical characteristics of this group, and the association with disease outcome. METHODS: DTC patients who underwent surveillance with simultaneous sTg and WBS were included. RESULTS: Two hundred seventy-two patients were included. Age at diagnosis was 46.5 ± 15.2 years, 79% were female. Mean duration of follow-up was 11.6 ± 6.8 years. Patients were categorised according to stimulation test results: sTg(-)/WBS(-) in 192/272 (70.6%); sTg(+) regardless of WBS results in 33/272 (12.1%); and sTg(-)/WBS(+) in 47/272 (17.3%) subjects. sTg > 10 mg/dl was considered positive. The three groups had similar demographic and pathologic characteristics. During follow-up, additional treatment was given in 77 patients (28.3%). Twelve (4.4%) developed distant metastases; 16 patients (5.8%) died. No deaths were disease-related. There was no difference in mortality rate between categories (P = 0.182). On multivariate analysis, additional treatment was associated with male gender (P = 0.046) and positive stimulation test results, either sTg (P < 0.001) or WBS (P < 0.001). Of the 47 WBS(+)/sTg(-) patients, 7(15%) were treated due to positive WBS results, including two who underwent additional surgery. CONCLUSION: A substantial proportion of stimulation test results were discordant. There was a significant association between WBS results and administration of additional treatment. Routine WBS had additional value for a small proportion of patients with no other evidence for disease and no indication for WBS.


Assuntos
Adenocarcinoma , Neoplasias da Glândula Tireoide , Adulto , Idoso , Feminino , Seguimentos , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tireoglobulina , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/tratamento farmacológico , Imagem Corporal Total
13.
Physiol Behav ; 250: 113796, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35358549

RESUMO

BACKGROUND: Fat-free mass (FFM) has been shown to be positively associated with hunger and energy intake, an association mediated by resting metabolic rate (RMR). However, FFM comprises a heterogeneous group of tissues with distinct metabolic rates, and it remains unknown how specific high-metabolic rate organs contribute to the degree of perceived hunger. OBJECTIVE: To examine whether FFM and its anatomical components were associated with fasting hunger when assessed at the tissue-organ level. DESIGN: Body composition (quantitative magnetic resonance and magnetic resonance imaging), RMR and whole-body glucose oxidation (indirect calorimetry), HOMA-index as a marker of insulin sensitivity, nitrogen balance and fasting hunger (visual analogue scales) were assessed in 21 healthy males (age = 25 ± 3y; BMI = 23.4 ± 2.1 kg/m2) after 3 days of controlled energy balance. RESULTS: FFM (rs = 0.39; p = 0.09), RMR (rs = 0.52; p = 0.02) and skeletal muscle mass (rs = 0.57; p = 0.04), but not fat mass (rs = -0.01; p = 0.99), were positively associated with fasting hunger. The association between the combined mass of high-metabolic rate organs (i.e., brain, liver, kidneys and heart; rs = 0.58; p = 0.006) and fasting hunger was stronger than with FFM as a uniform body component. The strongest individual association was between liver mass and fasting hunger (rs = 0.51; p = 0.02). No associations were observed between glucose parameters, markers of insulin sensitivity and fasting hunger. The encephalic measure, an index of brain-to-body energy allocation, was negatively associated with fasting hunger (rs = -0.51; p = 0.02). CONCLUSIONS: Fasting hunger was more strongly associated with the combined mass of high-metabolic rate organs than with FFM as a uniform body component, highlighting the importance of integrating individual tissue-organ masses and their functional correlates into homeostatic models of human appetite. The association between liver mass and fasting hunger may reflect its role in ensuring the brain's basal energy needs are met.


Assuntos
Fome , Resistência à Insulina , Adulto , Metabolismo Basal/fisiologia , Composição Corporal/fisiologia , Metabolismo Energético/fisiologia , Jejum , Glucose , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Imagem Corporal Total , Adulto Jovem
14.
Int J Comput Assist Radiol Surg ; 17(4): 673-681, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35279802

RESUMO

PURPOSE: Whole-body bone scintigraphy (WBS) is one of the common imaging methods in nuclear medicine. It is a time-consuming, tedious, and error-prone issue for physicians to determine the location of bone lesions which is important for the qualitative diagnosis of bone lesions. In this paper, an automatic fine-grained skeleton segmentation method for WBS is developed. METHOD: The proposed method contains four steps. In the first step, a novel denoising method is proposed to remove the noise from WBS which benefits the location of the skeleton. In the second step, a restoration method based on gray probability distribution is developed to repair the partial contamination caused by the high local density of radionuclide. Then, the standardization for WBS is performed by the exact histogram matching. Finally, the deformation field between the atlas and the input WBS is calculated by registration, and the segmentation mask of the input WBS is obtained by wrapping the segmentation mask of the atlas with the deformation field. RESULTS: The experimental results show that the proposed method outperforms the traditional registration (Morphon): mean square error decreased from [Formula: see text] to [Formula: see text], peak signal-to-noise ratio increased from 21.26 to 26.92, and mean structural similarity increased from 0.9986 to 0.9998. CONCLUSIONS: Our experiments show that the proposed method can achieve robust and fine-grained results which outperform the traditional registration method, indicating it could be helpful in clinical application. To the best of our knowledge, this is the first work that implements a fully automated fine-grained skeleton segmentation method for WBS.


Assuntos
Osso e Ossos , Imagem Corporal Total , Algoritmos , Osso e Ossos/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Cintilografia , Razão Sinal-Ruído , Imagem Corporal Total/métodos
15.
Eur J Radiol ; 150: 110239, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35290908

RESUMO

PURPOSE: To report the frequencies of incidental findings on whole body MRI (WB-MRI) around the hip and to characterize the significance of incidental findings in a general population. MATERIALS AND METHODS: This retrospective study included 7287 cases that underwent WB-MRI as part of a preventive health screening. WB-MR images were reviewed by two musculoskeletal radiologists in consensus. According to clinical severity and urgency of medical intervention, each finding was classified into two subgroups as clinically significant and insignificant. The clinically significant group included findings that suggested abnormalities requiring further evaluation or follow-up, such as avascular necrosis (AVN), bone tumor (enchondroma), soft tissue tumor, and fracture. The clinically less significant group included subcortical cyst, bone marrow edema, para-labral cyst, simple bone cysts, and ganglion cysts. RESULTS: The prevalence of clinically significant and less significant incidental findings of the hip on WB-MRI was substantial overall. The incidences were recorded as 1.2% and 19.9%, respectively. Besides bone and soft tissue tumor or tumor-like lesions, AVN of the femoral head was one of the findings with a 0.3% prevalence. CONCLUSIONS: An awareness of the prevalence of incidental findings can be helpful for radiologists and clinicians when interpreting WB-MRI for health screening and explaining the results to subjects.


Assuntos
Cistos , Neoplasias de Tecidos Moles , Humanos , Achados Incidentais , Imageamento por Ressonância Magnética , Programas de Rastreamento , Prevalência , Estudos Retrospectivos , Imagem Corporal Total/métodos
16.
J Radiol Prot ; 42(2)2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35354135

RESUMO

We aimed to evaluate the impact of a low-dose whole-body computed tomography (WBCT) protocol on radiation doses in paediatric major trauma patients. Retrospective cohort study of paediatric trauma patients (<16 years) at a national level 1 paediatric trauma centre (PTC) over a 6 year period prior and post introduction of a low-dose WBCT protocol (2014-2019). Demographic data, patient characteristics, CT device, and exposure information including scan range, dose-length product, and volume CT dose index were collected. Effective dose (ED) and exposure parameters were compared before and after protocol introduction. Forty-eight patients underwent WBCT during the study period. Prior to introduction of the low-dose protocol (n= 18), the ED was 20.6 mSv (median 20.1 ± 5.3 mSv [range 12.5-30.7]). After introduction of the low-dose WBCT protocol (n= 30), mean ED was 4.8 mSv (median 2.6 ± 5.0 [range: 0.8-19.1]). This resulted in a reduction of 77% in mean ED (pvalue <0.001). Significant radiation dose reduction of 77% can be achieved with low-dose WBCT protocols in PTCs.


Assuntos
Traumatismo Múltiplo , Imagem Corporal Total , Criança , Humanos , Doses de Radiação , Estudos Retrospectivos , Suíça , Tomografia Computadorizada por Raios X/métodos , Imagem Corporal Total/métodos
17.
J Comput Assist Tomogr ; 46(2): 231-235, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35297579

RESUMO

OBJECTIVES: Scoliosis is a common orthopedic problem in patients with neurofibromatosis 1 (NF1). Spinal deformities are found in 77% of all NF1 cases, with no widely accepted etiology. This study aimed to evaluate the frequency and types of scoliosis in NF1 patients using whole-body magnetic resonance imaging and to assess the association of intraspinal and paraspinal tumors with the imaging findings of scoliosis. METHODS: A total of 122 NF1 patients with whole-body magnetic resonance imaging were found from the electronic medical records. Ninety-seven cases that met the inclusion criteria were identified. All patients underwent 3-T magnetic resonance imaging with automated software fusion of the 3 sets of short TI inversion recovery and 3-dimensional T1-weighted coronal images. Frequency and location of scoliosis and intraspinal and paraspinal tumors were recorded. Patients with severe dystrophic-type scoliosis were separately identified, and Cobb angles were measured for all such cases. Association analysis was performed. A P value less than 0.05 was considered statistically significant. RESULTS: Ninety-seven patients with NF1 were evaluated. Two had prior spinal surgery and were excluded. The final sample of 95 patients included 33 (35%) men and 62 (65%) women with a mean ± SD body mass index of 25.82 (4.96) kg/m2. Of the 95 patients, 43 (45.3%) had scoliosis, 13 of 43 (30.2%) of which were severely angled. Of the 95 patients, 25 (26.3%) had locoregional tumor presence. Intraclass correlation for Cobb angles measured 0.99 (confidence interval, 0.98-1.0). Fisher exact test determined no association between scoliosis and presence of either paraspinal or intraspinal tumors (P = 0.485). There was also no association between the tumors and severe dystrophic scoliosis (P = 1.0). CONCLUSIONS: This study found no association between the presence of locoregional spinal tumors and scoliosis in NF1 patients. This work adds to the body of knowledge of scoliosis in NF1 patients and infers that presence of scoliosis should not mandate immediate search for locoregional spinal tumors.


Assuntos
Neurofibromatose 1 , Escoliose , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Masculino , Neurofibromatose 1/complicações , Neurofibromatose 1/diagnóstico por imagem , Escoliose/diagnóstico por imagem , Imagem Corporal Total
18.
Tomography ; 8(2): 560-569, 2022 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-35314623

RESUMO

Background: Specification of adipose tissues by whole-body magnetic resonance imaging (MRI) was performed and related to pulmonary function parameters in a population-based cohort. Methods: 203 study participants underwent whole-body MRI and pulmonary function tests as part of the KORA (Cooperative Health Research in the Augsburg Region) MRI study. Both visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were derived from the T1-Dixon sequence, and hepatic adipose tissue from the proton density fat fraction (PDFFhepatic). Associations between adipose tissue parameters and spirometric indices such as forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and Tiffeneau-index (FEV1/FVC) were examined using multivariate linear regression analysis excluding cofounding effects of other clinical parameters. Results: VAT (ß = -0.13, p = 0.03) and SAT (ß = -0.26, p < 0.001), but not PDFFhepatic were inversely associated with FEV1, while VAT (ß = -0.27, p < 0.001), SAT (ß = -0.41, p < 0.001), and PDFFhepatic (ß = -0.17, p = 0.002) were inversely associated with FVC. PDFFhepatic was directly associated with the Tiffeneau index (ß = 2.46, p < 0.001). Conclusions: In the adjusted linear regression model, VAT was inversely associated with all measured spirometric parameters, while PDFFhepatic revealed the strongest association with the Tiffeneau index. Non-invasive adipose tissue quantification measurements might serve as novel biomarkers for respiratory impairment.


Assuntos
Imageamento por Ressonância Magnética , Imagem Corporal Total , Tecido Adiposo/diagnóstico por imagem , Humanos , Gordura Intra-Abdominal/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Gordura Subcutânea
19.
Emerg Radiol ; 29(3): 449-454, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35165773

RESUMO

BACKGROUND: Whole body CT in the setting of trauma has been shown to improve patient outcomes and decrease mortality in the emergency department (ED). Our institutional WBCT protocol allows for easy inclusion of the lower extremities, circumventing the need for diagnostic radiographs of the lower extremities. We hypothesized that this WBCT protocol would decrease time in the ED, reduce time to ED discharge, and decrease the number of lower extremity radiographs obtained in this patient population. PURPOSE: To assess patient throughput in the ED by determining total time in the ED, number of lower extremity radiographs, cost of radiographs, and total cost of imaging before and after the implementation of a WBCT protocol for trauma. METHODS: The trauma registry from an urban level 1 trauma center was searched for blunt trauma patients 6 months before and 6 months after the implementation of a WBCT protocol for trauma. Time between admission and discharge from the ED, total number of radiographs, total radiographs cost, total cost of ED imaging, and radiation dose estimations before and after WBCT implementation were calculated. RESULTS: There was a statistically significant decrease in time in the ED (76 min, p = 0.033) and number of lower extremity radiographs (decreased by 2 per patient, p < 0.01) following the implementation of the WBCT for trauma protocol. The cost of radiographs was decreased by 28.5% (p = 0.013) but the total cost of ED imaging was increased by approximately 4 × (p < 0.0001). Calculated effective radiation dose to the lower extremities increased by a factor of 1.9 × after implementation of WBCT for trauma. CONCLUSIONS: Implementation of a WBCT protocol for trauma resulted in statistically significant decreased time in the ED and decreased the number of radiographs at the expense of increased imaging costs and radiation exposure.


Assuntos
Fraturas Ósseas , Traumatismos da Perna , Serviço Hospitalar de Emergência , Fraturas Ósseas/diagnóstico por imagem , Humanos , Traumatismos da Perna/diagnóstico por imagem , Extremidade Inferior/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Centros de Traumatologia , Imagem Corporal Total/métodos
20.
Nucl Med Commun ; 43(5): 518-528, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35102077

RESUMO

INTRODUCTION: In this study, the optimal input parameters point spread function (PSF) and the number of iterations of the Richardson-Lucy algorithm were experimentally determined to restore Tc-99 m methyl diphosphonate (MDP) whole-body bone scan images. MATERIALS AND METHODS: The experiment was performed on 60 anonymized Tc-99 m MDP whole-body bone scan images. Ten images were used for estimating the optimum value of PSF and the number of iterations to restore scintigraphic images. The remaining 50 images were used for validation of estimated parameters. The image quality of observed and restored images was assessed objectively using blind/referenceless image spatial quality evaluator (BRISQUE), mean brightness (MB), discrete entropy (DE), and edge-based contrast measure (EBCM) image quality metrics. Image quality was subjectively assessed by two nuclear medicine physicians (NMPs) by comparing the restored image quality with observed image quality and assigning a score to each image on the scale of 0-5. RESULTS: Based on BRISQUE, MB, DE, and EBCM scores, the restored images were significantly sharper, less bright, had more detailed information, and had less contrast around edges compared to the input images. The restored images had improved resolution based on visual assessment as well; NMPs assigned an average image quality score of 4.00 to restored images. Maximum resolution enhancement was noticed at PSF (size: 11 pixels, sigma: 1.75 pixels) and the number of iterations = 10. With the increase in the number of iterations, noise also gets amplified along with resolution enhancement and affects the detectability of small lesions; in the case of relatively low noisy input images, the number of iterations = 5 gave better results. CONCLUSION: Tc-99 m MDP bone scan images were restored to improve image quality using the Richardson-Lucy algorithm. The optimum value of the PSF parameter was found to be of size = 11 pixels and sigma = 1.75 pixels.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X , Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Cintilografia , Imagem Corporal Total
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