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1.
J Imaging Inform Med ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926263

RESUMO

Standardized reporting of multiparametric prostate MRI (mpMRI) is widespread and follows international standards (Pi-RADS). However, quantitative measurements from mpMRI are not widely comparable. Although T2 mapping sequences can provide repeatable quantitative image measurements and extract reliable imaging biomarkers from mpMRI, they are often time-consuming. We therefore investigated the value of quantitative measurements on a highly accelerated T2 mapping sequence, in order to establish a threshold to differentiate benign from malignant lesions. For this purpose, we evaluated a novel, highly accelerated T2 mapping research sequence that enables high-resolution image acquisition with short acquisition times in everyday clinical practice. In this retrospective single-center study, we included 54 patients with clinically indicated MRI of the prostate and biopsy-confirmed carcinoma (n = 37) or exclusion of carcinoma (n = 17). All patients had received a standard of care biopsy of the prostate, results of which were used to confirm or exclude presence of malignant lesions. We used the linear mixed-effects model-fit by REML to determine the difference between mean values of cancerous tissue and healthy tissue. We found good differentiation between malignant lesions and normal appearing tissue in the peripheral zone based on the mean T2 value. Specifically, the mean T2 value for tissue without malignant lesions was (151.7 ms [95% CI: 146.9-156.5 ms] compared to 80.9 ms for malignant lesions [95% CI: 67.9-79.1 ms]; p < 0.001). Based on this assessment, a limit of 109.2 ms is suggested. Aditionally, a significant correlation was observed between T2 values of the peripheral zone and PI-RADS scores (p = 0.0194). However, no correlation was found between the Gleason Score and the T2 relaxation time. Using REML, we found a difference of -82.7 ms in mean values between cancerous tissue and healthy tissue. We established a cut-off-value of 109.2 ms to accurately differentiate between malignant and non-malignant prostate regions. The addition of T2 mapping sequences to routine imaging could benefit automated lesion detection and facilitate contrast-free multiparametric MRI of the prostate.

2.
Ned Tijdschr Geneeskd ; 1682024 02 06.
Artigo em Holandês | MEDLINE | ID: mdl-38415705

RESUMO

In this article, we will address 10 questions about anxiety that are relevant to doctors who encounter this in their practice. This often occurs in the primary care setting, where individuals with anxiety frequently present with somatic complaints. A focused medical history, including questions about the use and withdrawal of psychoactive substances, can assist in the diagnostic process. Psychoeducation may be sufficient, otherwise cognitive-behavioral therapy can be conducted. In cases of non-response, serotonergic antidepressants represent a treatment option. Half of the individuals with anxiety symptoms experience remission, while the other half have a recurrent or chronic course, which may be accompanied by comorbid depression.


Assuntos
Terapia Cognitivo-Comportamental , Médicos , Humanos , Ansiedade/epidemiologia , Ansiedade/terapia , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/epidemiologia , Transtornos de Ansiedade/terapia
3.
Ned Tijdschr Geneeskd ; 1652021 06 24.
Artigo em Holandês | MEDLINE | ID: mdl-34346608

RESUMO

Many diseases in patients with multimorbidity show interactions, which can be divided in random, causal, complicated of synergistic interactions. Diagnostic reasoning in general should be expanded with a goal assessment when single disease directed guidelines are not applicable to limit diagnostic burden and troubling incidental findings without added diagnostic value. Disease directed diagnostic guidelines are not well adapted to symptoms and complaints of patients with multimorbidity, which urges to first explain these based on progression of the multimorbidity, and only if necessary, expand this to diagnostic work-up for new diseases. Shared decision making on additional diagnostic investigations should anticipate and safeguard added therapeutic value of diagnostic results. New instruments such as causal loop diagrams, which clarify interactions between the individual diseases, may support this multimorbidity targeted diagnostic reasoning.


Assuntos
Multimorbidade , Resolução de Problemas , Tomada de Decisão Compartilhada , Humanos
4.
Clin Physiol Funct Imaging ; 41(2): 173-180, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33210817

RESUMO

OBJECTIVES: To determine the differences and challenging aspects of dynamic magnetic resonance defecography (MRD) compared to conventional defecography (CD) in diagnostic of clinical symptomatic pelvic floor dysfunction. METHODS: Fifty patients (44 females, 6 males; mean age: 57 years) with symptomatic pelvic floor dysfunction underwent both examinations, CD and MRD. Results were retrospectively intra-individual and interindividual evaluated in this multicentre study. Visibility and accuracy in diagnosis and classification of rectal prolapse, rectocele, enterocele, sigma diverticula and Cul-de-sac phenomenon/syndrome were observed. Differences were analysed using Mann-Whitney U test. P-values < 0.05 were considered as statistically significant. RESULTS: CD was significantly superior to MRD in diagnosis and grading of rectal prolapse (p < .001), diagnosis and metric measurements of rectoceles (p = .016), diagnosis of elongated sigmoid colon (p = .008) and Cul-de-sac phenomenon and syndrome, respectively (p = .015; p = .008). MRD revealed equal results to CD in detection, localization, tendency to retention and enlargement of rectoceles (p = .337) and findings of enteroceles (p = .604) as well as sigma diverticula (p = .149). CONCLUSIONS: The complementary use of both examination methods, CD and MRD, is important to achieve a comprehensive look on every aspect of pelvic floor disorders and gain optimal results in detection and evaluation of all major disorders of the pelvic floor.


Assuntos
Distúrbios do Assoalho Pélvico , Defecografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Distúrbios do Assoalho Pélvico/diagnóstico por imagem , Retocele , Estudos Retrospectivos
5.
Curr Med Imaging Rev ; 15(4): 373-379, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31989906

RESUMO

PURPOSE: To investigate image quality, and radiation dose between ECG-gated singlesource and dual-source CT Angiography (CTA) protocols for planning of Trans-catheter Aortic Valve Implantation (TAVI) with a reference non ECG-gated single-source protocol. METHODS: A total of 120 patients were included in four groups: Non ECG-gated single-source (SS), ECG-gated single-source (SSECG), ECG-gated dual-source high-pitch (DSECG), or non-ECG-gated dual-source high-pitch mode (DS). Qualitative image quality of the aortic annulus, aortic valve, and coronary ostia as well as presence of motion or stair-step artefacts of the thoracic aorta were independently assessed by two readers. Quantitative image quality was assessed to calculate contrast to noise ratio. RESULTS: Subjective and objective scoring of motion artefacts was significantly reduced in SSECG, DSECG and DS (p= 0.010). The imaging length was comparable between groups. Aortic annulus, aortic valve, and coronary ostia were reliably evaluable in all patients with SSECG, DSECG and DS protocols. CONCLUSION: High-pitch, dual-source CT angiography of the whole aorta with or without ECG gating is a dose-efficient and time-saving examination strategy before TAVI. However acquisition timing within the cardiac cycle needs to be taken into account.


Assuntos
Aorta/diagnóstico por imagem , Aortografia/métodos , Técnicas de Imagem de Sincronização Cardíaca/métodos , Angiografia por Tomografia Computadorizada/métodos , Eletrocardiografia/métodos , Substituição da Valva Aórtica Transcateter/métodos , Adulto , Idoso , Valva Aórtica/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Planejamento de Assistência ao Paciente , Doses de Radiação
6.
Eur Radiol ; 29(5): 2553-2559, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30547199

RESUMO

OBJECTIVES: Increasing awareness of potential side effects from gadolinium-based contrast agents has underlined the need for contrast-free magnetic resonance imaging (MRI). Numerous recent articles evaluated the risk of potential brain deposits, with the result that research is putting the focus more on alternative unenhanced imaging techniques. The aim of this study was to determine the need for contrast media for chest MRI in primary staging and follow-up care of lymphoma. METHODS: This monocentric, retrospective study encompassed patients under 25 years of age who had undergone histopathological examination of thoracic lymph nodes and at least one chest MRI examination with unenhanced and contrast-enhanced sequences. Seven different thoracic lymph node stations including mediastinal, hilar, periclavicular, and axillary regions were evaluated by two readers regarding lesion diameter, number, shape, necrosis, and infiltration of surrounding structures. Findings were categorized into suspicious (> 1 cm; round; necrosis; infiltration) or non-suspicious. RESULTS: Fifty-one patients (mean age, 16.0 ± 3.7 yrs) with thoracic Hodgkin (70.6%) and non-Hodgkin lymphoma (25.5%) and lymphadenopathy (3.9%) were retrospectively included. Most lymph nodes categorized as suspicious were located in the mediastinal station (86.4%). High agreement (κ = 0.81) between unenhanced and contrast-enhanced sequences was found for both suspicious and non-suspicious lymph nodes. Significant (p < 0.001), but small difference (1 mm) was observed only in sizing mediastinal lymph nodes (all other p > 0.05). No significant difference (smallest p = 0.08) was shown for the use of five different types of contrast media. CONCLUSION: MRI in young patients with thoracic lymphoma can safely be done without the use of contrast agent. KEY POINT: • Thoracic magnetic resonance imaging in young lymphoma patients can safely be done without gadolinium-based contrast agents.


Assuntos
Linfoma/diagnóstico , Imageamento por Ressonância Magnética/métodos , Compostos Organometálicos/farmacologia , Neoplasias Torácicas/diagnóstico , Adolescente , Adulto , Criança , Pré-Escolar , Meios de Contraste/farmacologia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Adulto Jovem
7.
Oncol Res Treat ; 41(7-8): 438-442, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30007958

RESUMO

BACKGROUND: We evaluated survival data and local tumor control in 2 groups of patients with hepatocellular carcinoma (HCC) treated with different chemotherapeutic agents for transarterial chemoembolization (TACE). METHODS: 28 patients (median age 63 years) with HCC were repeatedly treated with chemoembolization at 4-week intervals. 20 patients had Barcelona Clinic Liver Cancer (BCLC) stage B, while 8 patients obtained chemoembolization for bridging purposes (BCLC stage A). In total, 98 chemoembolizations were performed (median 3.0 treatments/patient). The administered chemotherapeutic agent comprised either mitomycin only (n = 14; 50%) or mitomycin in combination with irinotecan (n = 14; 50%). Lipiodol plus degradable starch microspheres was used for all embolizations. Local tumor response was assessed by magnetic resonance imaging using modified Response Evaluation Criteria in Solid Tumors (mRECIST) criteria. Progression-free survival (PFS) was evaluated. RESULTS: In the mitomycin-irinotecan group, complete response (CR) was observed in 21.4%, partial response (PR) in 42.9%, stable disease (SD) in 28.6%, and progressive disease (PD) in 7.1%. In the mitomycin group, PR was observed in 57.2% of patients, SD in 21.4%, and PD in 21.4% (p = 0.043). The PFS of patients after chemoembolization with mitomycin was 4 months compared to the significantly longer PFS of 12 months in the mitomycin-irinotecan group (p = 0.003). CONCLUSION: Chemoembolization of HCC with mitomycin and irinotecan is the preferred treatment option for achieving local control and better PFS.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/diagnóstico por imagem , Intervalo Livre de Doença , Óleo Etiodado/administração & dosagem , Feminino , Humanos , Irinotecano/administração & dosagem , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Amido/administração & dosagem
8.
Br J Radiol ; 91(1088): 20180269, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29792729

RESUMO

OBJECTIVE: To evaluate low-tube-voltage 90-kVp CT pulmonary angiography (CTPA) with advanced modeled iterative reconstruction algorithm (Admire) compared to 120-kVp equivalent dual-energy (DE) acquisition with regards to radiation exposure, image quality and diagnostic accuracy for pulmonary embolism (PE) assessment. METHODS: CTPA studies of 40 patients with suspected PE (56.7 ± 16.3 years) performed on a third-generation 192-slice dual-source CT scanner were retrospectively included. 120-kVp equivalent linearly-blended (60% 90-kVp, 40% 150-kVp) and 90-kVp images were reconstructed. Attenuation and noise of the pulmonary trunk were measured to calculate contrast-to-noise ratios (CNR). Three radiologists assessed the presence of central and segmental PE and diagnostic confidence. Interobserver agreement was calculated using intraclass correlation coefficient (ICC). Radiation exposure was assessed as effective dose (ED). RESULTS: Pulmonary trunk CNR values were significantly increased in 90-kVp compared to linearly-blended series (15.4 ± 6.3 vs 11.3 ± 4.6, p < 0.001). Diagnostic accuracy for PE assessment was similar in both series with excellent interobserver agreement (p = 0.48; ICC, 0.83; p = 0.48). Overall confidence for PE assessment was rated excellent for both series with a significant advantage for linearly-blended series (p < 0.001; 4.1 vs 3.8). ED was reduced by 37.2% with 90-kVp compared to 120-kVp equivalent image series (1.1 ± 0.6 vs 1.7 ± 0.7 mSv, p < 0.001). CONCLUSION: 90-kVp CTPA with Admire provided increased quantitative image quality with similar diagnostic accuracy and confidence for PE assessment compared to 120-kVp equivalent acquisition, while radiation dose was reduced by 37.2%. Advances in knowledge: 90-kVp CTPA with an advanced iterative reconstruction algorithm results in excellent image quality and reduction of radiation exposure without limiting diagnostic performance.


Assuntos
Algoritmos , Angiografia por Tomografia Computadorizada/métodos , Processamento de Imagem Assistida por Computador/métodos , Artéria Pulmonar/diagnóstico por imagem , Embolia Pulmonar/diagnóstico por imagem , Exposição à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Reprodutibilidade dos Testes , Estudos Retrospectivos
9.
BMC Cancer ; 18(1): 188, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29444653

RESUMO

BACKGROUND: To evaluate survival data and local tumor control after transarterial chemoembolization in two groups with different embolization protocols for the treatment of HCC patients. METHODS: Ninty-nine patients (mean age: 63.6 years), 78 male (78.8%) with HCC were repeatedly treated with chemoembolization in 4-week-intervals. Eighty-eight patients had BCLC-Stage-B and in 11 patients, chemoembolization was performed for bridging (BCLC-Stage-A). In total, 667 chemoembolization treatments were performed (mean 6.7 treatments/patient). The administered chemotherapeutic agent included mitomycin. For embolization, lipiodol only (n = 51;51.5%; mean age 63.8 years; 38 male), or lipiodol plus degradable starch microspheres (DSM) (n = 48; 48.5%; mean age 63.4 years; 40 male) were used. The local tumor response was assessed by MRI using Response Evaluation Criteria in Solid Tumors 1.1 (RECIST 1.1). Patient survival times were evaluated using Kaplan-Meier curves and log-rank tests. RESULTS: The local tumor control in the lipiodol-group was: PR (partial response) in 11 (21.6%), SD (stable disease) in 32 (62.7%) and PD (progressive disease) in 8 cases (15.7%). In the lipiodol-DSM-group, PR was seen in 14 (29.2%), SD in 22 (45.8%), and PD in 12 (25.0%) individuals (p = 0.211). The median survival of patients after chemoembolization with lipiodol was 25 months and in the lipiodol-DSM-group 28 months (p = 0.845). CONCLUSION: Our data suggest a slight benefit of the use of lipiodol and DSM in comparison of using lipiodol only for chemoembolization of HCC in terms of local tumor control and survival data, this trend did not reach the level of significance.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Quimioembolização Terapêutica , Sistemas de Liberação de Medicamentos , Neoplasias Hepáticas/tratamento farmacológico , Microesferas , Amido , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidade , Quimioembolização Terapêutica/métodos , Óleo Etiodado/administração & dosagem , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidade , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Estadiamento de Neoplasias , Amido/química , Resultado do Tratamento
10.
Eur J Radiol ; 99: 111-117, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29362140

RESUMO

PURPOSE: To investigate the impact of traditional (VMI) and noise-optimized virtual monoenergetic imaging (VMI+) algorithms on quantitative and qualitative image quality, and the assessment of stenosis in carotid and intracranial dual-energy CTA (DE-CTA). MATERIALS AND METHODS: DE-CTA studies of 40 patients performed on a third-generation 192-slice dual-source CT scanner were included in this retrospective study. 120-kVp image-equivalent linearly-blended, VMI and VMI+ series were reconstructed. Quantitative analysis included evaluation of contrast-to-noise ratios (CNR) of the aorta, common carotid artery, internal carotid artery, middle cerebral artery, and basilar artery. VMI and VMI+ with highest CNR, and linearly-blended series were rated qualitatively. Three radiologists assessed artefacts and suitability for evaluation at shoulder height, carotid bifurcation, siphon, and intracranial using 5-point Likert scales. Detection and grading of stenosis were performed at carotid bifurcation and siphon. RESULTS: Highest CNR values were observed for 40-keV VMI+ compared to 65-keV VMI and linearly-blended images (P < 0.001). Artefacts were low in all qualitatively assessed series with excellent suitability for supraaortic artery evaluation at shoulder and bifurcation height. Suitability was significantly higher in VMI+ and VMI compared to linearly-blended images for intracranial and ICA assessment (P < 0.002). VMI and VMI+ showed excellent accordance for detection and grading of stenosis at carotid bifurcation and siphon with no differences in diagnostic performance. CONCLUSION: 40-keV VMI+ showed improved quantitative image quality compared to 65-keV VMI and linearly-blended series in supraaortic DE-CTA. VMI and VMI+ provided increased suitability for carotid and intracranial artery evaluation with excellent assessment of stenosis, but did not translate into increased diagnostic performance.


Assuntos
Estenose das Carótidas/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Algoritmos , Artefatos , Artéria Carótida Primitiva/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Humanos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Ruído , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Estudos Retrospectivos , Razão Sinal-Ruído , Insuficiência Vertebrobasilar/diagnóstico por imagem
11.
Acta Radiol ; 59(8): 909-916, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29105487

RESUMO

Background Image quality benefits from high-pitch scanning in agitated patients by reducing acquisition time. Purpose To compare image quality and exposure parameters in patients with maxillofacial trauma on second- and third-generation dual-source computed tomography (DSCT). Material and Methods Four groups were compared. Group 1 was examined on second-generation DSCT (120 kV/50 mAs, pitch 3.0). The other three groups were examined on third-generation DSCT. Group 2 was scanned with 120 kV/50 mAs, pitch 2.2. Automated exposure control (AEC) was used in group 3 and group 4 with pitch factors of 2.2 and 3.0, respectively. Images of third-generation DSCT were reconstructed with iterative reconstruction (IR), of second-generation DSCT with filtered back-projection. CTDIvol, acquisition time, and image quality were compared. Results Thirty patients were included in each group. Average CTDIvol (2.76 ± 0.00 mGy, 2.66 ± 0.00 mGy, 0.74 ± 0.23 mGy, and 0.75 ± 0.17 mGy) was significantly lower on third-generation DSCT with AEC ( P < 0.001). Subjective image quality was rated worst in group 4 due to strong high-pitch artifacts, while in the remaining three groups it was rated good or very good with good inter-observer agreement (k > 0.64). Average acquisition time was significantly shorter with third-generation DSCT (0.47 s, 0.36 s, 0.38 s, 0.30 s; P < 0.001). Conclusion Third-generation DSCT yields faster acquisition times and substantial dose reduction with AEC. A pitch of 2.2 should be preferred, as it results in fewer artifacts. If AEC is used, latest IR ensures that diagnostic image quality is guaranteed.


Assuntos
Artefatos , Traumatismos Maxilofaciais/diagnóstico por imagem , Seios Paranasais/diagnóstico por imagem , Agitação Psicomotora/complicações , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Movimento (Física) , Reprodutibilidade dos Testes , Razão Sinal-Ruído , Fatores de Tempo , Adulto Jovem
12.
World J Clin Oncol ; 8(4): 343-350, 2017 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-28848701

RESUMO

AIM: To evaluate the clinical value and efficiency of trans-arterial chemoperfusion (TACP) in patients with liver metastases from breast cancer (BC) and colorectal cancer (CRC). METHODS: We treated 36 patients with liver metastases of BC (n = 19, 19 females) and CRC (n = 17; 8 females, 9 males) with repeated TACP. The treatment interval was 4 wk. TACP was performed with gemcitabine (1000 mg/m2) and mitomycin (10 mg/m2), administered within 1 h after positioning the catheter tip in the hepatic artery. Before treatment, the size, location, tumour volume, vascularization and number of liver tumours were evaluated using magnetic resonance imaging (MRI). Tumour response was evaluated according to the Response Evaluation Criteria in Solid Tumors guidelines. RESULTS: TACP using gemcitabine and mitomycin for metastases from CRC and BC was performed without any serious side effects. The follow-up MRI showed a therapeutic response in 84.2% of the BC patients - stable disease 47.4% and partial response 36.8%. A progression was seen in 15.8%. CRC patients showed a therapeutic response in 52.9% of cases. A progression of the disease was documented in 47.1% of the patients with CRC. These data show that TACP in patients with liver metastases of BC leads to a significantly better therapeutic response compared with CRC patients (P = 0.042). The median survival time was 13.2 mo for the BC patients, which is significantly longer than for CRC patients at 9.3 mo (P = 0.001). CONCLUSION: TACP for liver metastases of BC appears to be a safe and effective palliative treatment with improved outcomes in comparison to patients with CRC.

13.
J Comput Assist Tomogr ; 41(5): 817-822, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28448407

RESUMO

PURPOSE: The aim of this study was to evaluate the impact of automated attenuation-based tube potential selection (ATPS) on image quality and radiation dose exposure parameters at a computed tomography angiography (CTA) lower-extremity runoff. MATERIALS AND METHODS: Two hundred forty patients (156 men, 84 women) underwent CTA examinations of the lower-extremity runoff on a second-generation dual-source computed tomography system: 120 patients at a fixed tube potential of 120 kV and a tube current of 180 reference mAs, another 120 patients using automated ATPS. Volume computed tomography dose index (CTDIvol), dose-length-product (DLP), body diameters, noise, signal-to-noise ratio, and subjective image quality were compared. RESULTS: In the ATPS group, 80 kV was automatically selected in 102 patients, 100 kV in 15 patients, and 120 kV in 3 patients; 140 kV was not chosen in any of the cases. The median CTDIvol of 4.81 mGy (2.2-10.6 mGy) and DLP of 568 mGy⋅cm (203-1324 mGy⋅cm) in the ATPS group were significantly lower compared with the CTDIvol of 8.1 mGy (4.4-14.4 mGy) and DLP of 1027.5 mGy⋅cm (509-1806 mGy⋅cm) in the fixed 120-kV group (P < 0.01). Image quality was comparable (P > 0.05). CONCLUSION: Automated ATPS allows for significant dose savings in lower-extremity runoff CTA, whereas image quality remains constant at a high level.


Assuntos
Angiografia por Tomografia Computadorizada/instrumentação , Angiografia por Tomografia Computadorizada/métodos , Extremidade Inferior/irrigação sanguínea , Extremidade Inferior/diagnóstico por imagem , Doença Arterial Periférica/diagnóstico por imagem , Doses de Radiação , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão Sinal-Ruído
14.
Eur J Radiol ; 89: 208-214, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28267541

RESUMO

OBJECTIVES: To investigate image quality, presence of motion artifacts and effects on radiation dose of 80kVp high-pitch dual-source CT (DSCT) in combination with an advanced modeled iterative reconstruction algorithm (ADMIRE) of the pediatric chest compared to single-source CT (SSCT). MATERIALS AND METHODS: The study was approved by the institutional review board. Eighty-seven consecutive pediatric patients (mean age 9.1±4.9years) received either free-breathing high-pitch (pitch 3.2) chest 192-slice DSCT (group 1, n=31) or standard-pitch (pitch 1.2) 128-slice SSCT (group 2, n=56) with breathing-instructions by random assignment. Tube settings were similar in both groups with 80 kVp and 74 ref. mAs. Images were reconstructed using FBP for both groups. Additionally, ADMIRE was used in group 1. Effective thorax diameter, image noise, and signal-to-noise ratio (SNR) of the pectoralis major muscle and the thoracic aorta were calculated. Motion artifacts were measured as doubling boarders of the diaphragm and the heart. Images were rated by two blinded readers for overall image quality and presence of motion artifacts on 5-point-scales. Size specific dose estimates (SSDE, mGy) and effective dose (ED, mSv) were calculated. RESULTS: Age and effective thorax diameter showed no statistically significant differences in both groups. Image noise and SNR were comparable (p>0.64) for SSCT and DSCT with ADMIRE, while DSCT with FBP showed inferior results (p<0.01). Motion artifacts were reduced significantly (p=0.001) with DSCT. DSCT with ADMIRE showed the highest overall IQ (p<0.0001). Radiation dose was lower for DSCT compared to SSCT (median SSDE: 0.82mGy vs. 0.92mGy, p<0.02; median ED: 0.4 mSv vs. 0.48mSv, p=0.02). CONCLUSIONS: High-pitch 80kVp chest DSCT in combination with ADMIRE reduces motion artifacts and increases image quality while lowering radiation exposure in free-breathing pediatric patients without sedation.


Assuntos
Aorta Torácica/diagnóstico por imagem , Músculos Peitorais/diagnóstico por imagem , Tórax/diagnóstico por imagem , Adolescente , Algoritmos , Artefatos , Criança , Feminino , Humanos , Masculino , Movimento (Física) , Doses de Radiação , Exposição à Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Respiração , Estudos Retrospectivos , Razão Sinal-Ruído , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas
15.
Pediatr Radiol ; 47(7): 831-837, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28352977

RESUMO

BACKGROUND: Most of the applied radiation dose at CT is in the lower photon energy range, which is of limited diagnostic importance. OBJECTIVE: To investigate image quality and effects on radiation parameters of 100-kVp spectral filtration single-energy chest CT using a tin-filter at third-generation dual-source CT in comparison to standard 100-kVp chest CT. MATERIALS AND METHODS: Thirty-three children referred for a non-contrast chest CT performed on a third-generation dual-source CT scanner were examined at 100 kVp with a dedicated tin filter with a tube current-time product resulting in standard protocol dose. We compared resulting images with images from children examined using standard single-source chest CT at 100 kVp. We assessed objective and subjective image quality and compared radiation dose parameters. RESULTS: Radiation dose was comparable for children 5 years old and younger, and it was moderately decreased for older children when using spectral filtration (P=0.006). Effective tube current increased significantly (P=0.0001) with spectral filtration, up to a factor of 10. Signal-to-noise ratio and image noise were similar for both examination techniques (P≥0.06). Subjective image quality showed no significant differences (P≥0.2). CONCLUSION: Using 100-kVp spectral filtration chest CT in children by means of a tube-based tin-filter on a third-generation dual-source CT scanner increases effective tube current up to a factor of 10 to provide similar image quality at equivalent dose compared to standard single-source CT without spectral filtration.


Assuntos
Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Estudos Retrospectivos
16.
Ital J Pediatr ; 43(1): 4, 2017 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-28057068

RESUMO

BACKGROUND: Computed-tomography-guided interventions are attractive for tissue sampling of paediatric tumor lesions; however, it comes with exposure to ionizing radiation. The aim of this study was to analyse the radiation dose, accuracy and speed of CT-guided interventions in paediatric patient cohort. METHODS: We retrospectively reviewed CT-guided interventions over a 10 -year period in 65 children. The intervention site consisted of bones in 38, chest (lung) in 15 and abdomen (liver, lymph nodes) in 12 cases. Radiation dose and duration of the procedures were analysed. The statistical analysis was performed using dedicated statistical software (BiAS 8.3.6 software, Epsilon Verlag, North Hasted). RESULTS: All interventions were performed successfully. Mean target access path to lesion within the patients was 6.0 cm (min 3.5 cm, max 11.2 cm). Time duration to complete intervention was 25:15 min (min 17:03 min, max 43:00 min). The dose-length product (DLP) of intervention scan was 29.5 mGy · cm (min 6 mGy · cm, max 85 mGy · cm) with the lowest dose for biopsies in the region of the chest (p = 0.04). CONCLUSIONS: With justified indications, CT-guided paediatric interventions are safe, effective and can be performed both, with short intervention times and low radiation exposure.


Assuntos
Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Tomografia Computadorizada por Raios X , Criança , Humanos , Biópsia Guiada por Imagem/métodos , Doses de Radiação , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Tempo , Tomografia Computadorizada por Raios X/métodos
17.
Eur J Radiol Open ; 3: 259-263, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27844041

RESUMO

PURPOSE: To determine the value of the 2D multiple-echo data image combination (MEDIC) sequence relative to the short-tau inversion recovery (STIR) sequence regarding the depiction of chondral lesions in the patellofemoral joint. MATERIALS AND METHODS: During a period of 6 month patients with acute pain at the anterior aspect of the knee, joint effusion and suspected chondral lesion defect in the patellofemoral joint underwent MRI including axial MEDIC and STIR imaging. Patients with chondral lesions in the patellofemoral joint on at least one sequence were included. The MEDIC and STIR sequence were quantitatively compared regarding the patella cartilage-to-effusion contrast-to-noise ratio (CNR) and qualitatively regarding the depiction of chondral lesions independently scored by two radiologists on a 3-point scale (1 = not depicted; 2 = blurred depicted; 3 = clearly depicted) using the Wilcoxon-Mann-Whitney-Test. For the analysis of inter-observer agreement the Cohen's Weighted Kappa test was used. RESULTS: 30 of 58 patients (male: female, 21:9; age: 44 ± 12 yrs) revealed cartilage lesions (fissures, n = 5 including fibrillation; gaps, n = 15; delamination, n = 7; osteoarthritis, n = 3) and were included in this study. The STIR-sequence was significantly (p < 0.001) superior to the MEDIC-sequence regarding both, the patella cartilage-to-effusion CNR (mean CNR: 232 ± 61 vs. 40 ± 16) as well as the depiction of chondral lesion (mean score: 2.83 ± 0.4 vs. 1.75 ± 0.7) with substantial inter-observer agreement in the rating of both sequences (κ = 0.76-0.89). CONCLUSION: For the depiction of chondral lesions in the patellofemoral joint, the axial STIR-sequence should be chosen in preference to the axial MEDIC-sequence.

18.
Cancer Imaging ; 16(1): 33, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27724954

RESUMO

BACKGROUND: Evaluation of latest generation automated attenuation-based tube potential selection (ATPS) impact on image quality and radiation dose in contrast-enhanced chest-abdomen-pelvis computed tomography examinations for gynaecologic cancer staging. METHODS: This IRB approved single-centre, observer-blinded retrospective study with a waiver for informed consent included a total of 100 patients with contrast-enhanced chest-abdomen-pelvis CT for gynaecologic cancer staging. All patients were examined with activated ATPS for adaption of tube voltage to body habitus. 50 patients were scanned on a third-generation dual-source CT (DSCT), and another 50 patients on a second-generation DSCT. Predefined image quality setting remained stable between both groups at 120 kV and a current of 210 Reference mAs. Subjective image quality assessment was performed by two blinded readers independently. Attenuation and image noise were measured in several anatomic structures. Signal-to-noise ratio (SNR) was calculated. For the evaluation of radiation exposure, CT dose index (CTDIvol) values were compared. RESULTS: Diagnostic image quality was obtained in all patients. The median CTDIvol (6.1 mGy, range 3.9-22 mGy) was 40 % lower when using the algorithm compared with the previous ATCM protocol (median 10.2 mGy · cm, range 5.8-22.8 mGy). A reduction in potential to 90 kV occurred in 19 cases, a reduction to 100 kV in 23 patients and a reduction to 110 kV in 3 patients of our experimental cohort. These patients received significantly lower radiation exposure compared to the former used protocol. CONCLUSION: Latest generation automated ATPS on third-generation DSCT provides good diagnostic image quality in chest-abdomen-pelvis CT while average radiation dose is reduced by 40 % compared to former ATPS protocol on second-generation DSCT.


Assuntos
Abdome/diagnóstico por imagem , Neoplasias dos Genitais Femininos/diagnóstico por imagem , Pelve/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Meios de Contraste , Feminino , Neoplasias dos Genitais Femininos/patologia , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Doses de Radiação , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/normas
19.
AJR Am J Roentgenol ; 207(6): 1340-1349, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27680945

RESUMO

OBJECTIVE: The purpose of this study is to retrospectively evaluate local tumor control, time to tumor progression, and survival rates among patients with lung metastatic colorectal cancer who have undergone ablation therapy performed using laser-induced thermotherapy (LITT), radiofrequency ablation (RFA), or microwave ablation (MWA). MATERIALS AND METHODS: Data for this retrospective study were collected from 231 CT-guided ablation sessions performed for 109 patients (71 men and 38 women; mean [± SD] age, 68.6 ± 11.2 years; range, 34-94 years) from May 2000 to May 2014. Twenty-one patients underwent LITT (31 ablations), 41 patients underwent RFA (75 ablations), and 47 patients underwent MWA (125 ablations). CT scans were acquired 24 hours after each therapy session and at follow-up visits occurring at 3, 6, 12, 18, and 24 months after ablation. Survival rates were calculated from the time of the first ablation session, with the use of Kaplan-Meier and log-rank tests. Changes in the volume of the ablated lesions were measured using the Kruskal-Wallis method. RESULTS: Local tumor control was achieved in 17 of 25 lesions (68.0%) treated with LITT, 45 of 65 lesions (69.2%) treated with RFA, and 91 of 103 lesions (88.3%) treated with MWA. Statistically significant differences were noted when MWA was compared with LITT at 18 months after ablation (p = 0.01) and when MWA was compared with RFA at 6 months (p = 0.004) and 18 months (p = 0.01) after ablation. The overall median time to local tumor progression was 7.6 months. The median time to local tumor progression was 10.4 months for lesions treated with LITT, 7.2 months for lesions treated with RFA, and 7.5 months for lesions treated with MWA, with no statistically significant difference noted. New pulmonary metastases developed in 47.6% of patients treated with LITT, in 51.2% of patients treated with RFA, and in 53.2% of patients treated with MWA. According to the Kaplan-Meier test, median survival was 22.1 months for patients who underwent LITT, 24.2 months for those receiving RFA, and 32.8 months for those who underwent MWA. The overall survival rate at 1, 2, and 4 years was 95.2%, 47.6%, and 23.8%, respectively, for patients treated with LITT; 76.9%, 50.8%, and 8.0%, respectively, for patients treated with RFA; and 82.7%, 67.5%, and 16.6%, respectively, for patients treated with MWA. The log-rank test revealed no statistically significant difference among LITT, RFA, and MWA. The progression-free survival rate at 1, 2, 3, and 4 years was 96.8%, 52.7%, 24.0%, and 19.1%, respectively, for patients who underwent LITT; 77.3%, 50.2%, 30.8%, and 16.4%, respectively, for patients who underwent RFA; and 54.6%, 29.1%, 10.0%, and 1.0%, respectively, for patients who underwent MWA, with no statistically significant difference noted among the three ablation methods. CONCLUSION: LITT, RFA, and MWA can be used as therapeutic options for lung metastases resulting from colorectal cancer. Statistically significant differences in local tumor control revealed a potential advantage in using MWA. No differences in time to tumor progression or survival rates were detected when the three different ablation methods were compared.


Assuntos
Ablação por Cateter/mortalidade , Neoplasias Colorretais/secundário , Neoplasias Colorretais/cirurgia , Terapia a Laser/mortalidade , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/cirurgia , Micro-Ondas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/mortalidade , Feminino , Alemanha/epidemiologia , Humanos , Hipertermia Induzida/mortalidade , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento
20.
Br J Radiol ; 89(1064): 20151060, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27164030

RESUMO

The adequate treatment of non-resectable liver metastases from colorectal cancer which are resistant to systemic chemotherapy currently provides a great challenge. The aim is to identify and review key strategies in the treatment of colorectal liver metastases. A search for current literature on the topic of interventional strategies for colorectal metastases was performed in Medline in order to achieve this goal. Studies before 2005 and with <20 patients treated for colorectal metastases were excluded. Transarterial chemoembolization (TACE), transarterial embolization and selective internal radiation therapy (SIRT) were identified as examples of regional strategies for colorectal liver metastases, utilizing the unique blood supply of the liver. Radiofrequency ablation (RFA), microwave ablation (MWA) and cryoablation were selected as examples for currently available ablative techniques. Median survival in the key studies reviewed ranged from 7.7 to 28.6 for TACE, 8.3-12.6 for SIRT, 8.2-53.2 for RFA and 29-43 months for MWA. After review of the literature, it can be concluded that interventional oncologic therapies are a safe and effective method for treating colorectal liver metastases. The use of new chemotherapeutic agents for local therapy and new ablation technologies and techniques may increase patient survival and allows a neoadjuvant therapy setting. In addition, a combination of local therapies may be used to increase effectiveness in the future, which is subject to further research.

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