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1.
Blood Purif ; 49(6): 658-664, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32289781

RESUMO

BACKGROUND/AIMS: Uremic tumoral calcinosis (UTC) is a rare disease with metastatic tissue calcification in maintenance hemodialysis (HD) patients. However, limited data are available on the treatment of UTC in HD patients. This article mainly discusses the diagnostic findings and efficacy of treatment on HD patients with UTC. METHODS: A retrospective analysis was conducted based on the data of 13 cases of UTC, including their clinical features, biochemical indicators, imaging findings, diagnosis, therapeutic methods, and follow-up results. Parathyroidectomy (PTX) or drug treatment was determined based on intact parathyroid hormone (iPTH) levels and clinical symptoms. RESULTS: All 13 patients were diagnosed as UTC definitely by imaging examination. The predominant areas involved were the buttocks (4 cases, 30.77%), shoulders (4 cases, 30.77%), and elbows (3 cases, 23.08%). Based on the levels of iPTH, cases were categorized into 2 different groups: PTX treatment group was associated with high levels of iPTH, while drug treatment group (lanthanum carbonate or sevelamer with sodium thiosulfate) was associated with lower iPTH levels. After PTX treatment, there was a significant decrease in serum iPTH, calcium (Ca), phosphate (P), and alkaline phosphatase levels (p < 0.05). In drug treatment group, the serum p levels were decreased significantly, along with a finding that hemoglobin levels were increased (p < 0.05). All the UTC had lessened or even disappeared after 4-6 months treatment. CONCLUSIONS: Although most UTC patients have an increased iPTH, a small number had lower iPTH levels. Based on iPTH levels and clinical symptoms, the patients were treated with PTX or drug therapy. With proper treatment, UTC disappeared without the need for surgery to remove calcinosis tissue.


Assuntos
Calcinose/etiologia , Calcinose/terapia , Diálise Renal/efeitos adversos , Adulto , Biomarcadores/sangue , Calcinose/diagnóstico , Tomada de Decisão Clínica , Gerenciamento Clínico , Suscetibilidade a Doenças , Feminino , Humanos , Hiperparatireoidismo Secundário/complicações , Hiperparatireoidismo Secundário/metabolismo , Hiperparatireoidismo Secundário/terapia , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Hormônio Paratireóideo/metabolismo , Radiografia , Estudos Retrospectivos , Avaliação de Sintomas , Tomografia Computadorizada por Raios X
2.
Kidney Blood Press Res ; 43(3): 664-672, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29734173

RESUMO

BACKGROUND/AIMS: Cardiovascular disease (CVD) is an important cause of morbidity and mortality in hemodialysis patients. Vascular calcification is thought to play an important role in causing CVD. Soluble urokinase plasminogen activator receptor (suPAR) is a biomarker strongly predictive of cardiovascular outcomes in the pathogenesis of diabetic patients with renal disease treated with hemodialysis. We investigated the relationship between suPAR and coronary artery calcification (CAC) in patients undergoing maintenance hemodialysis. METHODS: A total of 99 adult hemodialysis patients were enrolled in this study. Plasma samples were analyzed for suPAR with an enzyme-linked immunosorbent assay and the CAC score was determined with multidetector computed tomography. The occurrence of cardiovascular events and all-cause mortality during follow-up were recorded from January 1, 2010 to June 1, 2016. RESULTS: In 99 patients treated with maintenance hemodialysis, 91 (91.9%) had varying degrees of CAC, and suPAR correlated positively with the CAC score in a Spearman analysis. In a mean follow-up period of 33 months, 36 patients (36.4%) experienced at least one cardiovascular event. When the quartiles of suPAR concentrations were used as the cutoff points for a subgroup analysis, the incidence of CVD and all-cause mortality was much higher in the higher quartiles of suPAR. In a univariate Cox regression analysis, high suPAR was a risk factor for CVD and all-cause mortality. CONCLUSION: suPAR is associated with the CAC score and is a risk factor for new-onset CVD in patients undergoing hemodialysis.


Assuntos
Calcinose/sangue , Doenças Cardiovasculares/sangue , Doença da Artéria Coronariana/patologia , Receptores de Ativador de Plasminogênio Tipo Uroquinase/sangue , Adulto , Idoso , Biomarcadores/sangue , Calcinose/complicações , Doenças Cardiovasculares/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Diálise Renal , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/terapia , Fatores de Risco , Solubilidade
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2094-7, 2016 Jul.
Artigo em Zh | MEDLINE | ID: mdl-30035891

RESUMO

The discrimination of tea varieties plays very important role in the production and sale of tea. It is of great significance for the study of a fast, easy and simple method for the identification of tea varieties. The combination of infrared spectroscopy detection technology and fuzzy clustering algorithm is one of the most effective and practical techniques in the detection of tea varieties. To realize the rapid discrimination of tea varieties, a novel generalized noise clustering (NGNC) was proposed based on fast generalized noise clustering (FGNC). Euclidean distance in the objective function of FGNC was replaced with the pth power of Euclidean distance and clustering accuracy was being improved. Emeishan Maofeng; high quality Leshan trimeresurus and low quality Leshan trimeresurus were prepared as the research object and the infrared reflectance (IR) spectra of tea samples were collected with FTIR-7600 infrared spectrometer. Firstly, the high-dimensional IR spectra of tea samples were reduced by principal component analysis (PCA). Secondly, linear discriminant analysis (LDA) was used to extract the discriminant information from the low-dimensional data. Finally, FGNC and NGNC were performed to identify tea varieties. The experimental results showed that in comparision with FGNC, NGNC has higher clustering accuracy, better cluster centers and faster convergence speed. Infrared spectroscopy coupled with NGNC, PCA and LDA could cluster IR spectra of tea samples quickly and correctly, which provided a new method and new idea for identifying tea varieties based on infrared spectroscopy and fuzzy clustering.

4.
J Immunother ; 46(2): 64-73, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36637978

RESUMO

Checkpoint inhibitor-related pneumonitis (CIP) is one of the most important immune checkpoint inhibitors side effects, and it is rare but fatal. Identifying patients at risk of refractory CIP before the start of CIP therapy is important for controlling CIP. We retrospectively analyzed the clinical data of 60 patients with lung cancer who developed CIP. Refractory CIP was defined as CIP with poor response to corticosteroid treatment, including CIP not relieved with corticosteroid administration or CIP recurrence during the corticosteroid tapering period. We analyzed clinical characteristics, peripheral blood biomarkers, treatment, and outcomes in nonrefractory and refractory CIP. Risk factors associated with refractory CIP were assessed. Among 60 patients with CIP, 16 (26.7%) had refractory CIP. The median onset time for patients with nonrefractory and those with refractory CIP was 16.57 (interquartile range [IQR], 6.82-28.14) weeks and 7.43 (IQR, 2.71-19.1) weeks, respectively. The level of lactate dehydrogenase (LDH) was significantly higher in the refractory CIP group at baseline (255 [222, 418] vs. 216 [183, 252], P =0.031) and at CIP onset (321.5 [216.75, 487.5] vs. 219 [198. 241], P =0.019). An LDH level >320 U/L at CIP onset was an independent risk factor of refractory CIP (odds ratio [OR], 8.889; 95% confidence interval [CI]: 1.294-61.058; P =0.026). The incidence of refractory CIP is high among patients with CIP. An increased LDH level at CIP onset is independently associated with refractory CIP. Monitoring LDH levels during immune checkpoint inhibitors treatment is recommended.


Assuntos
Neoplasias Pulmonares , Pneumonia , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Estudos Retrospectivos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/tratamento farmacológico , Pneumonia/diagnóstico , Pneumonia/etiologia , Fatores de Risco , Corticosteroides/uso terapêutico
5.
Med Phys ; 49(3): 1547-1558, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35026041

RESUMO

PURPOSE: Consolidation immunotherapy after completion of chemoradiotherapy has become the standard of care for unresectable locally advanced non-small cell lung cancer and can induce potentially severe and life-threatening adverse events, including both immune checkpoint inhibitor-related pneumonitis (CIP) and radiation pneumonitis (RP), which are very challenging for radiologists to diagnose. Differentiating between CIP and RP has significant implications for clinical management such as the treatments for pneumonitis and the decision to continue or restart immunotherapy. The purpose of this study is to differentiate between CIP and RP by a CT radiomics approach. METHODS: We retrospectively collected the CT images and clinical information of patients with pneumonitis who received immune checkpoint inhibitor (ICI) only (n = 28), radiotherapy (RT) only (n = 31), and ICI+RT (n = 14). Three kinds of radiomic features (intensity histogram, gray-level co-occurrence matrix [GLCM] based, and bag-of-words [BoW] features) were extracted from CT images, which characterize tissue texture at different scales. Classification models, including logistic regression, random forest, and linear SVM, were first developed and tested in patients who received ICI or RT only with 10-fold cross-validation and further tested in patients who received ICI+RT using clinicians' diagnosis as a reference. RESULTS: Using 10-fold cross-validation, the classification models built on the intensity histogram features, GLCM-based features, and BoW features achieved an area under curve (AUC) of 0.765, 0.848, and 0.937, respectively. The best model was then applied to the patients receiving combination treatment, achieving an AUC of 0.896. CONCLUSIONS: This study demonstrates the promising potential of radiomic analysis of CT images for differentiating between CIP and RP in lung cancer, which could be a useful tool to attribute the cause of pneumonitis in patients who receive both ICI and RT.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Pneumonite por Radiação , Carcinoma Pulmonar de Células não Pequenas/complicações , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Aprendizado de Máquina , Pneumonite por Radiação/diagnóstico por imagem , Pneumonite por Radiação/etiologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
6.
Pediatr Radiol ; 41(7): 858-66, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21534003

RESUMO

BACKGROUND: There are a limited number of reports on the technical and clinical feasibility of prospective electrocardiogram (ECG)-gated multi-detector computed tomography (MDCT) in infants with congenital heart disease (CHD). OBJECTIVE: To evaluate image quality and radiation dose at weight-based low-dose prospectively gated 256-slice MDCT angiography in infants with CHD. MATERIALS AND METHODS: From November 2009 to February 2010, 64 consecutive infants with CHD referred for pre-operative or post-operative CT were included. All were scanned on a 256-slice MDCT system utilizing a low-dose protocol (80 kVp and 60-120 mAs depending on weight: 60 mAs for ≤ 3 kg, 80 mAs for 3.1-6 kg, 100 mAs for 6.1-10 kg, 120 mAs for 10.1-15 kg). RESULTS: No serious adverse events were recorded. A total of 174 cardiac deformities, confirmed by surgery or heart catheterization, were studied. The sensitivity of MDCT for cardiac deformities was 97.1%; specificity, 99.4%; accuracy, 95.9%. The mean heart rate during scan was 136.7 ± 14.9/min (range, 91-160) with a corresponding heart rate variability of 2.8 ± 2.2/min (range, 0-8). Mean scan length was 115.3 ± 11.7 mm (range, 93.6-143.3). Mean volume CT dose index, mean dose-length product and effective dose were 2.1 ± 0.4 mGy (range, 1.5-2.8), 24.7 ± 5.9 mGy·cm (range, 14.7-35.8) and 1.6 ± 0.3 mSv (range, 1.1-2.5), respectively. Diagnostic-quality images were achieved in all cases. Satisfactory diagnostic quality for visualization of all/proximal/distal coronary artery segments was achieved in 88.4/98.8/80.0% of the scans. CONCLUSION: Low-dose prospectively gated axial 256-slice CT angiography is a valuable tool in the routine clinical evaluation of infants with CHD, providing a comprehensive three-dimensional evaluation of the cardiac anatomy, including the coronary arteries.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca/métodos , Angiografia Coronária/métodos , Cardiopatias Congênitas/diagnóstico por imagem , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste , Feminino , Cardiopatias Congênitas/fisiopatologia , Frequência Cardíaca , Humanos , Lactente , Recém-Nascido , Iohexol/análogos & derivados , Masculino , Estudos Prospectivos , Sensibilidade e Especificidade
7.
World J Clin Cases ; 9(30): 9108-9113, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34786393

RESUMO

BACKGROUND: As immune checkpoint inhibitors (ICIs) have become widely used in lung cancer treatment, immune-related adverse events (irAEs) warrant sufficient attention. Checkpoint inhibitor-related pneumonitis (CIP) is one of the most concerning adverse events as it is uncommon but life threatening. CASE SUMMARY: The patient whose case is reported here experienced three episodes of CIP in a span of 4 mon. Interestingly, the three episodes of CIP involved different regions of the lung separately. Taking these pneumonitis areas together makes nearly a whole lung area. CONCLUSION: This case showed that recurrent CIPs may occur repeatedly until the whole lung is involved, suggesting that the follow-up period of CIP should be long enough, and the rechallenge of ICI should be done with due caution.

8.
Eur J Radiol ; 126: 108905, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32145596

RESUMO

PURPOSE: To analyze the imaging manifestations of mediastinal hemangioma (MH) by CT and MRI to aid in its successful diagnosis and preoperative evaluation. METHODS: Seventeen cases of MH diagnosed by histopathology combined with CT and MRI were retrospectively collected; and their CT and MRI features, including the lesions' site and range, shape, size, margin, density or signal, enhancement pattern, mass-cardiovascular interface, mass-pulmonary interface, and other characteristics were evaluated. RESULTS: The anterior, middle, and posterior mediastinum were involved in 13, 13, and 8 cases, respectively. The masses size varied from 20 to 233 mm. Irregular, dumbbell-like, and oval masses were found in 13, 2, and 2 cases, respectively, while with pampiniform growth in 16 cases and expansive growth in 1 case. Mixed density, homogeneous density solid masses, and heterogeneous density masses with dominant fat were found in 9, 5, and 3 cases, respectively, showing mild or significant enhancement in aortic phase while no or mild enhancement in pulmonary artery phase. Draining veins were found in 16 cases and feeding arteries in 10 cases. Phleboliths were detected in 10 cases, splenic hemangiomas in 6 cases, and left lateral-chest-wall hemangioma in 1 case. In MRI sequences, mixed signal was found on T1WI and heterogeneous hypersignal with nodular or linear hyposignal on T2WI in 5 cases, mild or significant enhancement in 4 cases, draining veins in 2 cases, and no feeding arteries or phleboliths were seen. CONCLUSION: Presence of phleboliths, pampiniform growth pattern, and aberrant draining veins are relatively specific characteristics in diagnosing MH.


Assuntos
Hemangioma/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neoplasias do Mediastino/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Criança , Feminino , Hemangioma/patologia , Humanos , Masculino , Neoplasias do Mediastino/patologia , Mediastino/diagnóstico por imagem , Mediastino/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
10.
Coron Artery Dis ; 26(4): 308-16, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25714067

RESUMO

PURPOSE: To assess the impact of chest circumference (CC)-adjusted tube current and iterative reconstructions (iDose) on individualized radiation dose reduction and image quality (IQ) in ECG-triggered computed tomography coronary angiography (CTCA). MATERIALS AND METHODS: A total of 102 patients underwent retrospectively ECG-triggered CTCA utilizing CC-adapted tube current [mAs=1000×(0.051×CC-23.765)/900] and filtered back projection (FBP) reconstruction (group A). On the basis of the CC-adjusted tube current technique, 54 patients (group B) underwent retrospective ECG-triggered CTCA with a 20% mAs reduction compared with group A and 90 patients (group C) underwent prospective ECG-triggered CTCA with an 80% mAs reduction compared with group A; both groups B and C were reconstructed with FBP and iDose. Subjective IQ was assessed, and image noise, signal-to-noise, and contrast-to-noise ratios (SNR and CNR) were quantified. RESULTS: Patients in group A had the highest radiation dose, followed by group B and group C. iDose provided decreased image noise and increased SNR and CNR, as did subjective IQ. The image noise was higher and SNR and CNR in group B were obviously lower than those in group A with FBP, but in group B, iDose4 increased the mean objective IQ. There was no difference between group B with iDose and group A with FBP, as was the case with subjective IQ. CONCLUSION: The combination of a CC-adapted technique, prospective triggering, and partial iterative reconstruction techniques reduces the radiation dose significantly, without significant degradation of IQ.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca/métodos , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Intensificação de Imagem Radiográfica/métodos , Estudos Retrospectivos
11.
Hellenic J Cardiol ; 55(5): 393-401, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25243438

RESUMO

INTRODUCTION: We aimed to determine a potentially optimal body size index for adjusting the tube current in retrospective ECG-triggered helical 256-slice CT coronary angiography (CTCA) for individualized radiation dose control. METHODS: Consecutive patients (n=102) with suspected coronary artery disease underwent retrospective ECG-triggered CTCA with a 256-slice CT scanner. Body mass index (BMI), nipple level (NL) bust and six anthropometric body size indexes, including thoracic anteroposterior diameter at NL, chest circumference (CC) at NL, left main (LM) and right coronary artery (RCA) origin level, chest area (CAr) and chest attenuation (CAt) at RCA origin level were measured, and their correlation with image noise in the aorta was evaluated using linear regression. Pearson correlation analysis was performed respectively to determine the body size index that correlated best with the other body size indexes. An equation was derived to use the best correlated body size index for adjusting tube current. RESULTS: Linear regression demonstrated that CCRCA had the best correlation with image noise. Pearson correlation analysis showed that CCNL, CCLM and CArRCA had the closest linear relationship with CCRCA. The equations connecting CCRCA and tube current for males and females were XmA = 662 × (0.055 × CCRCA - 28.594) / 302 and XmA = 662 × (0.049 × CCRCA - 21.584) / 302, respectively, for a fixed image noise value of 30 HU. CONCLUSIONS: Tube current selection is different for males and females, particularly in patients with a small chest circumference. CCRCA is an ideal body index for appropriately adjusting tube current in CTCA for individualized radiation dose control.


Assuntos
Tamanho Corporal , Angiografia Coronária/instrumentação , Doença da Artéria Coronariana/diagnóstico por imagem , Eletrocardiografia/métodos , Tomografia Computadorizada Multidetectores/instrumentação , Lesões por Radiação/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Estudos Retrospectivos , Adulto Jovem
12.
Radiat Prot Dosimetry ; 156(3): 296-302, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23528327

RESUMO

The purpose of this study was to estimate patient doses during coronary angiography (CA) and different complex percutaneous transluminal coronary angioplasty (PTCA) procedures in China. Consecutive 290 patients (90 CA, 200 PTCA) with known or suspected coronary artery disease were enrolled prospectively into six groups. Differences in patient doses among the six groups were analysed, and the patient doses observed in this study were compared with the recent literature. The median dose area product values were 27.0 and 195.0 Gy cm(2) for CA and PTCA, respectively. The patient doses during CA were similar to those reported by other authors, while those during PTCA were higher. The differences in radiation doses depended on the complexity of the procedures. Enhanced knowledge of radiation doses may help cardiologists implement radiation-sparing procedures to minimise patient exposure.


Assuntos
Angioplastia Coronária com Balão , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Radiografia Intervencionista , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Doença da Artéria Coronariana/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doses de Radiação
13.
Eur J Radiol ; 81(11): 3146-53, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22677617

RESUMO

PURPOSE: To reduce radiation dose for retrospective ECG-triggered helical 256-slice CTCA by determining an optimal body size index to prospectively adjust tube current. METHODS: 102 consecutive patients with suspected CAD underwent retrospective ECG-triggered CTCA using 256-slice CT scanner. Six body size indexes including BMI, nipple level (NL) bust, thoracic anteroposterior diameter at NL, chest circumference (CC) at NL, left main and right coronary artery (RCA) origin level were measured and their correlation with noise was evaluated using linear regression. An equation was developed to use this index to adjust tube current. Additional 102 consecutive patients were scanned with the index-based mAs adjustment. A t-test for independent samples was used to compare radiation dose levels with and without the index-based mAs selection method. RESULTS: Linear regression indicated that CC RCA had the best correlation with noise (R2=0.603). Effective radiation dose was reduced from 16.6±0.9 to 9.8±2.7 mSv (p<0.01), i.e. 40.9% lower dose with the CC RCA-adapted tube current method. The image quality scores indicated no significant difference with and without the size-based mAs selection method. CONCLUSION: An accessible measure of body size, such as CC RCA, can be used to adapt tube current for individualized radiation dose control.


Assuntos
Tamanho Corporal , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doses de Radiação , Proteção Radiológica/métodos , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada Espiral/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Imagem de Sincronização Cardíaca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
14.
Acad Radiol ; 17(12): 1462-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20947387

RESUMO

RATIONALE AND OBJECTIVES: The aim of this study was to determine whether the administration of gadolinium diethylenetriamine penta-acetic acid (Gd-DTPA) significantly affects shimming and water suppression on kidney magnetic resonance spectroscopic prescanning and whether the impact of shimming and water suppression is changed with time after intravenous administration on a 3.0-T system. METHODS: Forty patients (two patients were excluded from analysis because of motion) were examined before and after the administration of Gd-DTPA (the interval between the right and left kidneys was approximately 40 seconds). Regions of interest were carefully positioned in the region of the corresponding location of both kidneys separately. Line widths (full width at half maximum) and water suppression were obtained. A paired t test for comparison of means was used. In addition, repeat measurements with a shorter time interval (obtained 120-130 seconds after the injection) and a longer time interval (obtained 150-160 seconds after the injection) were performed in five patients in the same regions of interest of the right kidney. Sequential ¹H magnetic resonance spectroscopic prescanning in the same region of interest was performed in one patient. RESULTS: The left kidney had slightly better shimming and water suppression effects than the right kidney after contrast agent administration (all P values < .01). The limiting resolution of both shimming and water suppression effects was decreased on enhanced images in both kidneys (all P values < .01). The longer time interval group had better shimming and water suppression effects than the shorter time interval group (all P values < .01). After the administration of Gd-DTPA in one patient, sequential values of shimming and water suppression in the right and left kidneys, respectively, were 13 Hz and 97% and 12 Hz and 97% prior to the examination, 34 Hz and 86% and 30 Hz and 88% at 5 minutes, 32 Hz and 89% and 27 Hz and 90% at 10 minutes, 28 Hz and 91% and 24 Hz and 91% at 15 minutes, and 24 Hz and 92% and 20 Hz and 92% at 25 minutes. CONCLUSIONS: Gd-DTPA exerts adverse effects on water suppression and shimming, both of which show a trend of becoming well gradually with time extension after the injection of Gd-DTPA. This phenomenon limits the diagnostic use of kidney magnetic resonance spectroscopy performed immediately after contrast-enhanced magnetic resonance imaging.


Assuntos
Meios de Contraste , Gadolínio DTPA , Rim/patologia , Imageamento por Ressonância Magnética/métodos , Prótons , Água/química , Adulto , Idoso , Meios de Contraste/efeitos adversos , Feminino , Gadolínio DTPA/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade
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