Assuntos
Maus-Tratos Infantis , Sistema Hipotálamo-Hipofisário/metabolismo , Relações Mãe-Filho , Sistema Hipófise-Suprarrenal/metabolismo , Transtornos de Estresse Pós-Traumáticos/patologia , Pré-Escolar , Intervenção Educacional Precoce , Feminino , Alemanha , Humanos , Lactente , Sistema Límbico/metabolismo , Masculino , Refugiados/psicologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologiaRESUMO
Peri-ocular necrotising fasciitis is a very rare ophthalmological clinical picture and is potentially fatal. This disease is caused by bacterial infection of the fasciae, which rapidly spreads. The present article reports a typical case of the disease and gives an overview of the typical clinical signs and symptoms of peri-ocular necrotising fasciitis.
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Blefarite/terapia , Infecções Oculares Bacterianas/terapia , Fasciite Necrosante/terapia , Doenças Orbitárias/terapia , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Blefarite/diagnóstico , Terapia Combinada/métodos , Desbridamento/métodos , Infecções Oculares Bacterianas/diagnóstico , Fasciite Necrosante/diagnóstico , Feminino , Humanos , Doenças Orbitárias/diagnóstico , Resultado do TratamentoRESUMO
PURPOSE: To implement automated CT dose data monitoring using the DICOM-Structured Report (DICOM-SR) in order to monitor dose-related CT data in regard to national diagnostic reference levels (DRLs). MATERIALS AND METHODS: We used a novel in-house co-developed software tool based on the DICOM-SR to automatically monitor dose-related data from CT examinations. The DICOM-SR for each CT examination performed between 09/2011 and 03/2015 was automatically anonymized and sent from the CT scanners to a cloud server. Data was automatically analyzed in accordance with body region, patient age and corresponding DRL for volumetric computed tomography dose index (CTDIvol) and dose length product (DLP). RESULTS: Data of 36,523 examinations (131,527 scan series) performed on three different CT scanners and one PET/CT were analyzed. The overall mean CTDIvol and DLP were 51.3% and 52.8% of the national DRLs, respectively. CTDIvol and DLP reached 43.8% and 43.1% for abdominal CT (n=10,590), 66.6% and 69.6% for cranial CT (n=16,098) and 37.8% and 44.0% for chest CT (n=10,387) of the compared national DRLs, respectively. Overall, the CTDIvol exceeded national DRLs in 1.9% of the examinations, while the DLP exceeded national DRLs in 2.9% of the examinations. Between different CT protocols of the same body region, radiation exposure varied up to 50% of the DRLs. CONCLUSION: The implemented cloud-based CT dose monitoring based on the DICOM-SR enables automated benchmarking in regard to national DRLs. Overall the local dose exposure from CT reached approximately 50% of these DRLs indicating that DRL actualization as well as protocol-specific DRLs are desirable. The cloud-based approach enables multi-center dose monitoring and offers great potential to further optimize radiation exposure in radiological departments. KEY POINTS: ⢠The newly developed software based on the DICOM-Structured Report enables large-scale cloud-based CT dose monitoring ⢠The implemented software solution enables automated benchmarking in regard to national DRLs ⢠The local radiation exposure from CT reached approximately 50â% of the national DRLs ⢠The cloud-based approach offers great potential for multi-center dose analysis.
Assuntos
Computação em Nuvem , Exposição à Radiação/estatística & dados numéricos , Monitoramento de Radiação/normas , Sistemas de Informação em Radiologia/estatística & dados numéricos , Sistemas de Informação em Radiologia/normas , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Benchmarking/métodos , Benchmarking/normas , Mineração de Dados/métodos , Alemanha , Guias como Assunto , Aprendizado de Máquina , Concentração Máxima Permitida , Processamento de Linguagem Natural , Reconhecimento Automatizado de Padrão , Doses de Radiação , Exposição à Radiação/normas , Monitoramento de Radiação/métodos , Monitoramento de Radiação/estatística & dados numéricos , Valores de Referência , Tomografia Computadorizada por Raios X/normasRESUMO
Interest in functional renal magnetic resonance imaging (MRI) has significantly increased in recent years. This review article provides an overview of the most important functional imaging techniques and their potential clinical applications for assessment of native and transplanted kidneys, with special emphasis on the clarification of renal tumors.
Assuntos
Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Testes de Função Renal/métodos , Neoplasias Renais/diagnóstico , Rim/patologia , Imageamento por Ressonância Magnética/métodos , Algoritmos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE: The purpose of this study was to evaluate potential causes of Transjugular intrahepatic portosystemic shunt (TIPS) dysfunction. MATERIAL AND METHODS: We retrospectively evaluated 26 patients who required TIPS revision (group I) and 24 patients who did not require any further intervention (group II) within the first two years following TIPS implantation. The distance of the distal end of the stent to the hepatocaval junction was measured. Furthermore, the angle between the stent and the portal vein (inflow) and the angle between the stent and the hepatic vein (outflow) were measured. Furthermore, the following data were evaluated: pre- and postinterventional portal pressure gradients, maximal postinterventional flow and blood values [C-reactive protein (CRP), bilirubin, glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT)]. RESULTS: Compared with control subjects, patients who required TIPS revision showed a significantly longer distance from the distal end of the stent to the hepatocaval junction (I: 17.3â±â10âmm, II: 6.7â±â5.7âmm, pâ<â0.001). There was a statistically significant correlation between the above named distance and the time to revision (Pearson's correlation coefficient, râ=â0.5, pâ=â0.01). In addition, patients with TIPS revision had a significantly larger angle of portalvenous inflow (alpha angle) than the control group (I: 100.5â±â31.5°, II: 64.5â±â31.6°, pâ<â0.001). CONCLUSION: Our results show that the distance from the end of the stent to the hepatocaval junction and the angle of portalvenous inflow are technical factors that may influence the shunt's patency rate. Of these two, the distance to the hepatocaval junction can be influenced easily by the interventionalist.
Assuntos
Sobrevivência de Enxerto/fisiologia , Veias Hepáticas/fisiologia , Circulação Hepática/fisiologia , Derivação Portossistêmica Transjugular Intra-Hepática , Stents , Grau de Desobstrução Vascular/fisiologia , Velocidade do Fluxo Sanguíneo , Análise de Falha de Equipamento , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Estudos Retrospectivos , Resultado do TratamentoRESUMO
AIM: To perform a systematic, large-scale analysis using the Digital Imaging and Communication in Medicine structured report (DICOM-SR) to assess the relationship between body mass index (BMI) and radiation exposure in abdominal CT. MATERIALS AND METHODS: A retrospective analysis of DICOM-SR of 3121 abdominal CT examinations between April 2013 and March 2014 was performed. All examinations were conducted using a 128 row CT system. Patients (mean age 61 ± 15 years) were divided into five groups according to their BMI: group A <20 kg/m(2) (underweight), group B 20-25 kg/m(2) (normal weight), group C 25-30 kg/m(2) (overweight), group D 30-35 kg/m(2) (obese), and group E > 35 kg/m(2) (extremely obese). CT dose index (CTDIvol) and dose-length product (DLP) were compared between all groups and matched to national diagnostic reference values. RESULTS: The mean CTDIvol and DLP were 5.4 ± 2.9 mGy and 243 ± 153 mGy.cm in group A, 6 ± 3.6 mGy and 264 ± 179 mGy.cm in group B, 7 ± 3.6 mGy and 320 ± 180 mGy.cm in group C, 8.1 ± 5.2 mGy and 375 ± 306 mGy.cm in group D, and 10 ± 8 mGy and 476 ± 403 mGy.cm in group E, respectively. Except for group A versus group B, CTDIvol and DLP differed significantly between all groups (p<0.05). Significantly more CTDIvol values exceeded national diagnostic reference values in groups D and E (2.1% and 6.3%) compared to group B (0.5%, p<0.05). CONCLUSION: DICOM-SR is a comprehensive, fast, and reproducible way to analyse dose-related data at CT. It allows for automated evaluation of radiation dose in a large study population. Dose exposition is related to the patient's BMI and is increased by up to 96% for extremely obese patients undergoing abdominal CT.
Assuntos
Índice de Massa Corporal , Doses de Radiação , Monitoramento de Radiação/estatística & dados numéricos , Radiografia Abdominal/métodos , Sistemas de Informação em Radiologia/estatística & dados numéricos , Tomografia Computadorizada por Raios X/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/diagnóstico por imagem , Obesidade Mórbida/diagnóstico por imagem , Estudos RetrospectivosRESUMO
AIM: To evaluate the influence of attenuation-based tube potential selection (ATPS) in combination with organ-specific dose reduction (OSDR) on radiation dose and image quality of contrast-enhanced chest computed tomography (CT) examinations. MATERIAL AND METHODS: Seventy consecutive patients (59.2 ± 16.1 years; 49 men; 21 women) were randomized into two groups and underwent contrast-enhanced chest CT using a 128 section CT scanner. CT examinations were performed as standard protocol in group A (n = 35) and with the activated novel dose-saving devices, OSDR and ATPS, in group B (n = 35). Objective [signal-to-noise (SNR) and contrast-to-noise ratio (CNR)] and subjective image quality (five-point scale; 1 = non diagnostic; 5 = excellent) as well as radiation dose (CTDIvol) were analysed. RESULTS: CTDIvol of the protocol using OSDR and ATPS was significantly lower than in standard chest CT examinations (3.4 ± 1 versus 6.1 ± 2.3 mGy; p < 0.001). Although the level of noise was slightly elevated in group B (14.1 ± 1.7 versus 11.4 ± 1.9 HU; p < 0.01), no significant differences in SNR (17.1 ± 5 versus 16.3 ± 4.7) or subjective image quality (mean score of 4.6 versus 4.4) were observed between both imaging protocols. CONCLUSION: Attenuation-based tube potential selection in combination with organ-specific dose reduction essentially reduces the dose of chest CT in patients with normal body mass index (BMI) in clinical routine while maintaining subjective and objective image quality.
Assuntos
Pneumonia/diagnóstico por imagem , Doses de Radiação , Idoso , Algoritmos , Meios de Contraste , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteção Radiológica , Razão Sinal-Ruído , Tórax/efeitos da radiação , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normasRESUMO
OBJECTIVE: To evaluate the prognostic value of hyperattenuating adrenal glands on contrast-enhanced CT of polytraumatised patients. METHODS: Two hundred ninety-two patients (195 men and 97 women, mean age 45.3 ± 23.3 years) were included in this retrospective study. CT examinations were performed 60 s after intravenous injection of contrast material. Image analysis was performed by two radiologists. Patients were assigned to one of two groups according to the attenuation of the adrenal gland [group 1: adrenal glands ≥ inferior vena cava (IVC); group 2: adrenal glands < IVC]. RESULTS: Eighteen patients (42.2 years ± 24.2) were assigned to group 1 and 274 patients (48.4 years ± 22.4) to group 2. The average adrenal density was 150.8 ± 36.1 HU in group 1 and 83.7 ± 23.6 HU in group 2 (P < 0.0001). Eight of the 18 patients in group 1 (44.4%) and 33 of the 274 patients in group 2 (12.4%) died during hospitalisation (P < 0.05). Mean adrenal enhancement was significantly higher in patients who died (101.9 ± 40.6 HU) compared with survivors (86.1 ± 27.0 HU; P < 0.001). CONCLUSION: Hyperattenuation of adrenal glands is associated with a higher mortality rate in polytraumatised patients and may serve as a predictor of poor clinical outcome. KEY POINTS: ⢠Hyperattenuating adrenal glands can be observed in 6.2% of polytraumatised patients. ⢠Hyperattenuating adrenal glands indicate poor clinical outcome in polytraumatised patients. ⢠In polytraumatised patients, hyperattenuating adrenal glands are associated with a high mortality rate. ⢠Adrenal enhancement is higher amongst patients who died than amongst survivors.
Assuntos
Glândulas Suprarrenais/diagnóstico por imagem , Meios de Contraste , Traumatismo Múltiplo/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Meios de Contraste/administração & dosagem , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/mortalidade , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Taxa de Sobrevida/tendênciasRESUMO
PURPOSE: To compare the apparent diffusion coefficient (ADC) in non-small cell lung cancer lesions with standardized uptake values (SUV) derived from combined 18F-fluoro-deoxy-glucose-positron emission tomography/magnetic resonance imaging (FDG-PET/MRI) and those derived from FDG-PET/CT. MATERIALS AND METHODS: In 18 consecutive patients with histologically proven NSCLC (17 men, 1 woman; mean age, 61 ± 12 years), whole-body FDG-PET/MRI was performed after whole-body FDG-PET/CT. Regions of interest (ROI) encompassing the entire primary tumor were drawn into FDG-PET/CT and FDG-PET/MR images to determine the maximum and mean standardized uptake value (SUVmax; SUVmean) and into ADC parameter maps to assess mean ADC values. Pearson's correlation coefficients were calculated to compare SUV and ADC values. RESULTS: The SUVmax of NSCLC was 12.3 ± 4.8 [mean ±SD], and the SUVmean was 7.2 ± 2.8 as assessed by FDG-PET/MRI. The SUVmax and SUVmean derived from FDG-PET/CT and FDG-PET/MRI correlated well (R = 0.93; p < 0.001 and R = 0.92; p < 0.001, respectively). The ADCmean of the pulmonary tumors was 187.9 ± 88.8 × 10-5 mm²/s [mean ± SD]. The ADCmean exhibited a significant inverse correlation with the SUVmax (R = -0.72; p < 0.001) as well as with the SUVmean assessed by FDG-PET/MRI (R = -0.71; p < 0.001). CONCLUSION: This simultaneous PET/MRI study corroborates the assumed significant inverse correlation between increased metabolic activity on FDG-PET and restricted diffusion on DWI in NSCLC.Citation Format:
Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Fluordesoxiglucose F18/farmacocinética , Neoplasias Pulmonares/metabolismo , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons/métodos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Variações Dependentes do Observador , Projetos Piloto , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como AssuntoRESUMO
OBJECTIVES: The recent European Society of Urogenital Radiology (ESUR) guidelines for evaluation and reporting of prostate multiparametric magnetic resonance imaging (mp-MRI) include the Prostate Imaging Reporting and Data System (PI-RADS). The aim of this study was to investigate the inter-reader agreement of this scoring system. METHODS: One hundred and sixty-four lesions in 67 consecutive patients with elevated prostate-specific antigen and previously negative trans-rectal ultrasound (TRUS)-guided biopsy were scored retrospectively by three blinded readers using PI-RADS. Mp-MRI was performed at 3 T using T2-weighted, diffusion-weighted and dynamic contrast-enhanced imagings (T2WI, DWI, DCE-MRI). Histology of all lesions was obtained by in-bore MRI-guided biopsy. Cohen's kappa statistics were calculated for all readers. RESULTS: Inter-reader agreement for all lesions was good to moderate (T2WI, κ = 0.55; DWI, κ = 0.64; DCE-MRI, κ = 0.65). For tumour lesions it was good (T2WI, κ = 0.66; DWI, κ = 0.80; DCE-MRI, κ = 0.63) and for benign lesions moderate to good (T2WI, κ = 0.46; DWI, κ = 0.52; DCE-MRI, κ = 0.67). Using an overall PI-RADS score with a threshold of ≥10, we achieved a sensitivity of 85.7 %, and negative predictive value of 90.1 % for biopsied lesions. CONCLUSION: PI-RADS score shows good to moderate inter-reader agreement and enables standardised evaluation of prostate mp-MRI, with high sensitivity and negative predictive value. KEY POINTS: ⢠The European Society of Urogenital Radiology recently published guidelines for prostate MRI. ⢠We have evaluated inter-reader agreement of ESUR scoring for multiparametric prostate MRI. ⢠PI-RADS shows good to moderate inter-reader agreement and is clinically applicable. ⢠PI-RADS achieves in our series high sensitivity and negative predictive value for biopsied lesions. ⢠PI-RADS can be used as standardised scoring system in prostate cancer detection.
Assuntos
Biópsia Guiada por Imagem/normas , Imageamento por Ressonância Magnética/normas , Guias de Prática Clínica como Assunto , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Sociedades Médicas , Urologia , Idoso , Alemanha , Humanos , Masculino , Curva ROC , Padrões de Referência , Estudos RetrospectivosRESUMO
BACKGROUND: Due to the lack of symptoms an enterothorax frequently remains undetected in adults. Most symptomatic patients complain about bowel obstruction and a surgical repair of the diaphragmatic defect, particularly with a mesh, is mandatory. METHODS: This report presents the case of a 72-year-old female patient with a history of an upside-down stomach presenting with a painless jaundice and signs of liver cirrhosis. CLINICAL COURSE: The preoperative work-up revealed an enterothorax with compression of the main bile duct. Explorative laparotomy showed a liver cirrhosis with distinct intrahepatic cholestasis, a hydropic gallbladder and confirmed a right-sided diaphragmatic defect with an enterothorax. After reposition of the intestine, a cholecystectomy, bile duct revision and the closure of the diaphragmatic defect using a mesh were performed. CONCLUSION: Diaphragmatic defects are the basis for the formation of an enterothorax which may be associated with a complicated clinical course. Therefore, in cases of coincidental diagnosis, even in asymptomatic patients, surgical repair should be performed in order to prevent serious complications as presented in this case.
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Colestase Intra-Hepática/diagnóstico , Colestase Intra-Hepática/cirurgia , Hérnia Diafragmática/diagnóstico , Hérnia Diafragmática/cirurgia , Idoso , Colestase Intra-Hepática/etiologia , Diagnóstico Diferencial , Feminino , Hérnia Diafragmática/complicações , Humanos , Resultado do TratamentoRESUMO
In radiology the use of internet resources is part of the daily routine. The critical selection of but not the access to radiologically relevant information is the key topic in internet use. We offer a selection of reviewed internet sources for radiologists. We present sources that offer guidance in decision-making in daily routine as well as internet sources on technical topics in radiology. Case selection and radiological search engines are helpful sites to begin an internet research. Online anatomy sites can be of assistance for interpretation of findings in radiology. Writing and publishing scientific works in radiology requires access to numerous internet services, a positive selection of which are reviewed in the present article. A variety of freeware is available on the internet, some of which may be a substantial benefit to projects in radiology.
Assuntos
Mineração de Dados/métodos , Conhecimentos, Atitudes e Prática em Saúde , Disseminação de Informação/métodos , Internet , RadiologiaRESUMO
OBJECTIVES: Organ-specific dose reduction (OSDR) algorithms can reduce radiation on radiosensitive organs up to 59 %. This study evaluates the influence of a new OSDR algorithm on image quality of head and neck computed tomographic angiography (CTA) in clinical routine. METHODS: Sixty-two consecutive patients (68 ± 13 years) were randomised into two groups and imaged using 128-row multidetector CT. Group A (n = 31) underwent conventional CTA and group B (n = 31) CTA with a novel OSDR algorithm. Subjective and objective image quality were statistically compared. Subjective image quality was rated on a five-point scale. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated with region-of-interest measurements. RESULTS: The SNR of the common carotid artery and middle cerebral artery was 53.6 ± 22.7 and 43.3 ± 15.3 (group A) versus 54.1 ± 20.5 and 46.2 ± 14.6 (group B). The CNR was 40.0 ± 19.3 and 29.7 ± 12.0 (group A) compared with 40.7 ± 16.8 and 32.9 ± 10.9 (group B), respectively. Subjective image quality was excellent in both groups (mean score 4.4 ± 0.7 versus 4.4 ± 0.6). Differences between the two groups were not significant. CONCLUSIONS: The novel OSDR algorithm does not compromise image quality of head and neck CTA. Its application can be recommended for CTA in clinical routine to protect the thyroid gland and ocular lenses from unnecessary high radiation. KEY POINTS: ⢠Organ-specific dose reduction (OSDR) can significantly reduce radiation exposure during CT ⢠OSDR does not compromise image quality of head and neck CTA ⢠OSDR can significantly lower the risk of radiation damage to sensitive organs ⢠OSDR can easily be applied in routine clinical practice.
Assuntos
Angiografia Cerebral/métodos , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/patologia , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Algoritmos , Artéria Carótida Primitiva/patologia , Meios de Contraste/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/patologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Razão Sinal-RuídoRESUMO
AIM: To assess the feasibility of an unenhanced, flow-sensitive, alternating inversion recovery-balanced steady-state free precession (FAIR TrueFISP) arterial spin labelling (ASL) magnetic resonance imaging (MRI) technique for quantification of breast cancer perfusion. MATERIALS AND METHODS: Eighteen untreated breast tumour patients (mean age 53 ± 17 years, range 30-68 years) and four healthy controls (mean age 51 ± 14 years, range 33-68 years) were enrolled in this study and were imaged using a clinical 1.5 T MRI machine. Perfusion measurements were performed using a coronal single-section ASL FAIR TrueFISP technique in addition to a routine breast MRI examination. T1 relaxation time of normal breast parenchyma was determined in four healthy volunteers using the variable flip angle approach. The definitive diagnosis was obtained at histology after biopsy or surgery and was available for all patients. RESULTS: ASL perfusion was successfully acquired in 13 of 18 tumour patients and in all healthy controls. The mean ASL perfusion of invasive ductal carcinoma tissue was significantly higher (88.2 ± 39.5 ml/100 g/min) compared to ASL perfusion of normal breast parenchyma (24.9 ± 12.7 ml/100 g/min; p < 0.05) and invasive lobular carcinoma (30.5 ± 4.3 ml/100 g/min; p < 0.05). No significant difference was found between the mean ASL perfusion of normal breast parenchyma and invasive lobular carcinoma tissue (p = 0.97). CONCLUSION: ASL MRI enables quantification of breast cancer perfusion without the use of contrast material. However, its impact on diagnosis and therapy management of breast tumours has to be evaluated in larger patient studies.
Assuntos
Neoplasias da Mama/patologia , Angiografia por Ressonância Magnética/métodos , Neovascularização Patológica/patologia , Marcadores de Spin , Adulto , Idoso , Análise de Variância , Biópsia , Velocidade do Fluxo Sanguíneo , Neoplasias da Mama/cirurgia , Estudos de Casos e Controles , Estudos de Viabilidade , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Pessoa de Meia-Idade , Neovascularização Patológica/cirurgiaRESUMO
AIM: To evaluate electrocardiogram (ECG)-gated quiescent-interval single-shot magnetic resonance angiography (QISS-MRA) for nonenhanced assessment of peripheral artery occlusive disease (PAOD) using contrast-enhanced MRA (CE-MRA) as the reference standard. MATERIALS AND METHODS: Twenty-seven patients (mean age 66.6 ± 10.8 years) with PAOD were included in the study. QISS-MRA and CE-MRA of the lower extremity were performed using a 1.5 T MR scanner. In each patient, subjective image quality and the degree of stenosis were evaluated on a four-point scale for 15 predefined arterial segments. RESULTS: Twenty-five of the 27 patients were considered for analysis. Subjective image quality of QISS-MRA was significantly lower for the distal aorta, pelvic arteries, and femoral arteries as compared to CE-MRA (p < 0.01), while no significant difference was found for other vascular segments. The degree of stenosis was overestimated with QISS-MRA in 23 of 365 (6.3%) segments and underestimated in two of 365 (0.5%) segments. As compared to CE-MRA, QISS-MRA had a high sensitivity (98.6%), specificity (96%) as well as positive and negative predictive value (88.7 and 99.6%, respectively) for the detection of significant stenosis (≥50%). CONCLUSION: ECG-gated QISS-MRA is a promising imaging technique for reliable assessment of PAOD without the use of contrast material.
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Extremidade Inferior/irrigação sanguínea , Angiografia por Ressonância Magnética/métodos , Doença Arterial Periférica/diagnóstico , Idoso , Constrição Patológica/diagnóstico , Meios de Contraste , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
PURPOSE: To compare image quality of nonenhanced time-resolved 4D steady-state free precession MR angiography (4D SSFP MRA) of cerebral arteries at 1.5T and 3T. MATERIALS AND METHODS: 12 healthy subjects (mean age 29.4±6.9 years) were studied at both 1.5T and 3T. Two different positions of the acquisition slab were evaluated; in one acquisition the imaging slab included the carotid siphon ("S(low)"), in the other acquisition the imaging slab was placed superior to the carotid siphon ("S(high)"). Subjective image quality of cerebral arteries was assessed independently by two readers on a 4-point scale. Relative Signal-to-Noise-Ratio (SNR) was determined for the M1 segment of the middle cerebral artery. RESULTS: Subjective image quality of the anterior cerebral artery (segments A1, A2) was significantly higher at 1.5T as compared to 3T, while 3T provided significantly higher image quality for segment P3 of the posterior cerebral artery. For the middle cerebral artery (segments M1-M3), image quality was significantly higher at 1.5T than at 3T when the carotid siphon was included in the acquisition slab ("S(low)"), while no significant difference was found between 1.5T and 3T with "S(high)". Relative SNR was significantly higher at 1.5T (23.1±5.1) as compared to 3T (12.1±7.8) for "S(low)" and significantly higher at 3T (29.8±5.9) than at 1.5T (24.2±3.6) for "S(high)". CONCLUSION: Our results indicate that 4D SSFP MRA should preferably be performed at 1.5T with inclusion of the carotid siphon in the acquisition slab, which might be required for the assessment of intracranial collateral flow.
Assuntos
Algoritmos , Técnicas de Imagem de Sincronização Cardíaca/métodos , Angiografia Cerebral/métodos , Aumento da Imagem/métodos , Imageamento Tridimensional/métodos , Angiografia por Ressonância Magnética/métodos , Adulto , Meios de Contraste , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
PURPOSE: Medical curricula are currently being reformed in order to establish superordinated learning objectives, including, e.g., diagnostic, therapeutic and preventive competences. This requires a shifting from traditional teaching methods towards interactive and case-based teaching concepts. Conceptions, initial experiences and student evaluations of a novel radiological course Co-operative Learning In Clinical Radiology (CLICR) are presented in this article. MATERIALS AND METHODS: A novel radiological teaching course (CLICR course), which combines different innovative teaching elements, was established and integrated into the medical curriculum. Radiological case vignettes were created for three clinical teaching modules. By using a PC with PACS (Picture Archiving and Communication System) access, web-based databases and the CASUS platform, a problem-oriented, case-based and independent way of learning was supported as an adjunct to the well established radiological courses and lectures. Student evaluations of the novel CLICR course and the radiological block course were compared. RESULTS: Student evaluations of the novel CLICR course were significantly better compared to the conventional radiological block course. Of the participating students 52% gave the highest rating for the novel CLICR course concerning the endpoint overall satisfaction as compared to 3% of students for the conventional block course. The innovative interactive concept of the course and the opportunity to use a web-based database were favorably accepted by the students. Of the students 95% rated the novel course concept as a substantial gain for the medical curriculum and 95% also commented that interactive working with the PACS and a web-based database (82%) promoted learning and understanding. CONCLUSION: Interactive, case-based teaching concepts such as the presented CLICR course are considered by both students and teachers as useful extensions to the radiological course program. These concepts fit well into competence-oriented curricula.
Assuntos
Instrução por Computador/métodos , Currículo , Avaliação Educacional , Internato e Residência/estatística & dados numéricos , Sistemas de Informação em Radiologia/estatística & dados numéricos , Radiologia/educação , Interface Usuário-Computador , Estudos de Casos e Controles , Alemanha , EnsinoRESUMO
Especially in regard to the potential risks for the development of nephrogenic systemic fibrosis (NSF) following the administration of Gadolinium-based contrast material, nonenhanced MR angiography (MRA) methods are becoming ever more important. Besides well-established time-of-flight (TOF) and phase-contrast (PC) MRA, alternative imaging techniques based on balanced steady-state free precession (bSSFP) and turbo-spin-echo (TSE) sequences are increasingly used in combination with or without arterial spin labeling (ASL) strategies. This article provides an overview of the principles and clinical values of different nonenhanced MRA techniques. In addition, recent nonenhanced MRA developments are presented.
Assuntos
Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética/métodos , Velocidade do Fluxo Sanguíneo/fisiologia , Técnicas de Imagem de Sincronização Cardíaca , Angiografia Cerebral , Transtornos Cerebrovasculares/diagnóstico , Meios de Contraste/toxicidade , Angiografia Coronária , Gadolínio/toxicidade , Humanos , Imageamento Tridimensional/métodos , Rim/irrigação sanguínea , Dermopatia Fibrosante Nefrogênica/induzido quimicamente , Doença Arterial Periférica/diagnóstico , Sensibilidade e Especificidade , Técnica de SubtraçãoRESUMO
BACKGROUND: The purpose of this study was to evaluate the prevalence and clinical significance of incidental cardiac findings in non-ECG-gated chest CT. PATIENTS AND METHODS: Non-ECG-gated chest CT examinations of 300 patients were retrospectively analyzed for incidental cardiac findings. Subsequently, these findings were evaluated for their clinical relevance by a cardiologist. RESULTS: A total of 107 out of 300 examined patients had 174 incidental cardiac findings including coronary calcification (90), aortic/mitral valve calcification (42), iatrogenic changes (23), pericardial effusion (6), dilatation of the heart (4), myocardial changes (3), thrombus in the left ventricle (2), constrictive pericarditis (2) and atrial myxoma (1). Of the cardiac findings 51% were described in the written report and in 53 out of the 107 patients the cardiac findings were unknown. Newly detected incidental findings from 8 patients were rated as clinically significant: pericardial effusion (4), constrictive pericarditis (1), thrombus in the left ventricle (1), atrial myxoma (1) and dilatation of the heart (1). CONCLUSION: Incidental cardiac findings are frequent in non-ECG-gated chest CT and may have a high clinical relevance.
Assuntos
Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/epidemiologia , Achados Incidentais , Radiografia Torácica/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Imagem de Sincronização Cardíaca/estatística & dados numéricos , Alemanha/epidemiologia , Humanos , Pessoa de Meia-Idade , PrevalênciaRESUMO
PURPOSE: To evaluate the feasibility of T2' mapping in native kidneys and renal allografts. MATERIALS AND METHODS: Following approval of the local ethics committee, 24 renal allograft recipients and 10 control subjects (healthy volunteers) were included in this study. Multi-echo T2 and T2* imaging was performed on a 1.5 Tesla scanner. Allograft recipients were assigned to two groups: group a), 8 patients with good (glomerular filtration rate of more than 40 ml/min) allograft function and no evidence of transplant rejection, transplant renal artery stenosis or ureteral obstruction; group b), 16 patients with deterioration of renal graft function (glomerular filtration rate (GFR) of 40 ml/min or less). Two different imaging protocols were tested. RESULTS: The mean T2' relaxation parameters were 108.33 msec ± 13.34, 100.00 msec ± 18.89 and 124.57 msec ± 6.51 for groups a), b) and for control subjects, respectively. The reduction of T2' values in patient group b) was not statistically significant. However, significant correlations could be demonstrated between T2' values and the glomerular filtration rate (GFR) of renal allograft function. The reproducibility was tested and the coefficients of variation of T2' values in the cortex of transplanted kidneys were 11.1% within subjects and 11.3% between subjects. CONCLUSION: Our results indicate that T2' imaging is a promising non-enhanced technique, which seems to reveal information on transplant function. Further studies are required to determine the clinical value of T2' mapping for monitoring renal allograft recipients.