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1.
Eur J Radiol ; 176: 111529, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38810440

RESUMO

PURPOSE: This study investigated strategies to reduce pneumothorax risk in CT-guided lung biopsy. The approach involved administering 10 ml of 1 % lidocaine fluid in the subpleural or pleural space before lung puncture and utilizing the gravitational effect of pleural pressure with specific patient positioning. METHOD: We retrospectively analyzed 72 percutaneous CT-guided lung biopsies performed at a single center between January 2020 and April 2023. These were grouped based on fluid administration during the biopsy and whether the biopsies were conducted in dependent or non-dependent lung regions. Confounding factors like patient demographics, lesion characteristics, and procedural details were assessed. Patient characteristics and the occurrence of pneumothoraces were compared using a Kurskal-Wallis test for continuous variables and a Fisher's exact test for categorical variables. Multivariable logistic regression was used to identify potential confounders. RESULTS: Subpleural or pleural fluid administration and performing biopsies in dependent lung areas were significantly linked to lower peri-interventional pneumothorax incidence (n = 15; 65 % without fluid in non-dependent areas, n = 5; 42 % without fluid in dependent areas, n = 5; 36 % with fluid in non-dependent areas,n = 0; 0 % with fluid in dependent areas; p = .001). Even after adjusting for various factors, biopsy in dependent areas and fluid administration remained independently associated with reduced pneumothorax risk (OR 0.071, p<=.01 for lesions with fluid administration; OR 0.077, p = .016 for lesions in dependent areas). CONCLUSIONS: Pre-puncture fluid administration to the pleura and consideration of gravitational effects during patient positioning can effectively decrease pneumothorax occurrences in CT-guided lung biopsy.


Assuntos
Biópsia Guiada por Imagem , Pleura , Pneumotórax , Tomografia Computadorizada por Raios X , Humanos , Feminino , Masculino , Pneumotórax/prevenção & controle , Pneumotórax/etiologia , Biópsia Guiada por Imagem/métodos , Biópsia Guiada por Imagem/efeitos adversos , Estudos Retrospectivos , Pessoa de Meia-Idade , Pleura/patologia , Pleura/diagnóstico por imagem , Idoso , Pulmão/patologia , Pulmão/diagnóstico por imagem , Radiografia Intervencionista/métodos , Gravitação , Lidocaína/administração & dosagem , Posicionamento do Paciente/métodos , Adulto , Pressão , Punções
2.
Invest Radiol ; 59(2): 105-107, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862104

RESUMO

ABSTRACT: Next-generation gadolinium-based contrast agents (GBCAs), including both high relaxivity agents and targeted agents, and manganese-based agents with a high probably of commercial success are discussed in some depth. It is highly likely that gadopiclenol and gadoquatrane, both next-generation high relaxivity gadolinium-based compounds, will come in time to replace the current macrocyclic gadolinium chelates, despite the wide acceptance, very high safety profile, and high stability of the latter group. Current research has also made possible the development of 2 new targeted gadolinium chelates, which look very promising, with the potential to improve cancer detection (for both MT218 and ProCA32.collagen) as well as diseases of collagen (for the latter agent). Further work with manganese-based compounds, a topic left fallow for more than 20 years, has also now produced 2 agents with high potential for clinical use, one (manganese chloride tetrahydrate, administered orally) developed primarily for imaging of the liver and the other (Mn-PyC3A, administered intravenously) as a gadolinium-free replacement for the GBCAs. New detail has recently emerged regarding specific circumscribed subregions of the brain with specialized cytoarchitecture and functions in which high gadolinium concentrations are seen following injection of the linear agent gadodiamide. These findings pave the way for tailored functional neurological testing, specifically in patients at potential risk due to the continued wide use in many countries across the world of the linear GBCAs. The impact of artificial intelligence is also critically discussed, with its most likely applications being dose reduction and new clinical indications.


Assuntos
Meios de Contraste , Compostos Organometálicos , Humanos , Gadolínio , Inteligência Artificial , Manganês , Gadolínio DTPA , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Colágeno
3.
Radiol Case Rep ; 19(2): 791-793, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38111566

RESUMO

Gallstone ileus is a well-known cause of small bowel obstruction in the radiological literature. In the experience of these authors, gallstone ileus occurs more often in quiz cases for registrars than in the everyday casework of a radiologist. The here presented case of a gallstone ileus provides a good opportunity to summarize cause, clinical presentation, radiological findings, and treatment options for both those studying for the specialist examinations and those whose specialist examinations are long past.

4.
Invest Radiol ; 59(7): 495-503, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38117137

RESUMO

OBJECTIVES: Administration of gadolinium-based contrast agents (GBCA) in magnetic resonance imaging results in the long-term retention of gadolinium (Gd) in tissues and organs, including the bone, and may affect their function and metabolism. This study aims to investigate the effects of Gd and GBCA on the proliferation/survival, differentiation, and function of bone cell lineages. MATERIALS AND METHODS: Primary murine osteoblasts (OB) and osteoclast progenitor cells (OPC) isolated from C57BL/6J mice were used to test the effects of Gd 3+ (12.5-100 µM) and GBCA (100-2000 µM). Cultures were supplemented with the nonionic linear Gd-DTPA-BMA (gadodiamide), ionic linear Gd-DTPA (gadopentetic acid), and macrocyclic Gd-DOTA (gadoteric acid). Cell viability and differentiation were analyzed on days 4-6 of the culture. To assess the resorptive activity of osteoclasts, the cells were grown in OPC cultures and were seeded onto layers of amorphous calcium phosphate with incorporated Gd. RESULTS: Gd 3+ did not affect OB viability, but differentiation was reduced dose-dependently up to 72.4% ± 6.2%-73.0% ± 13.2% (average ± SD) at 100 µM Gd 3+ on days 4-6 of culture as compared with unexposed controls ( P < 0.001). Exposure to GBCA had minor effects on OB viability with a dose-dependent reduction up to 23.3% ± 10.2% for Gd-DTPA-BMA at 2000 µM on day 5 ( P < 0.001). In contrast, all 3 GBCA caused a dose-dependent reduction of differentiation up to 88.3% ± 5.2% for Gd-DTPA-BMA, 49.8% ± 16.0% for Gd-DTPA, and 23.1% ± 8.7% for Gd-DOTA at 2000 µM on day 5 ( P < 0.001). In cultures of OPC, cell viability was not affected by Gd 3+ , whereas differentiation was decreased by 45.3% ± 9.8%-48.5% ± 15.8% at 100 µM Gd 3+ on days 4-6 ( P < 0.05). Exposure of OPC to GBCA resulted in a dose-dependent increase in cell viability of up to 34.1% ± 11.4% at 2000 µM on day 5 of culture ( P < 0.001). However, differentiation of OPC cultures was reduced on day 5 by 24.2% ± 9.4% for Gd-DTPA-BMA, 47.1% ± 14.0% for Gd-DTPA, and 38.2% ± 10.0% for Gd-DOTA ( P < 0.001). The dissolution of amorphous calcium phosphate by mature osteoclasts was reduced by 36.3% ± 5.3% upon incorporation of 4.3% Gd/Ca wt/wt ( P < 0.001). CONCLUSIONS: Gadolinium and GBCA inhibit differentiation and activity of bone cell lineages in vitro. Thus, Gd retention in bone tissue could potentially impair the physiological regulation of bone turnover on a cellular level, leading to pathological changes in bone metabolism.


Assuntos
Diferenciação Celular , Sobrevivência Celular , Meios de Contraste , Camundongos Endogâmicos C57BL , Osteoblastos , Osteoclastos , Animais , Camundongos , Diferenciação Celular/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoblastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteoclastos/citologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Gadolínio/farmacologia , Gadolínio DTPA/farmacologia , Linhagem da Célula , Imageamento por Ressonância Magnética/métodos , Proliferação de Células/efeitos dos fármacos , Compostos Organometálicos/farmacologia
5.
Eur Radiol ; 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37870625

RESUMO

OBJECTIVES: The purpose of this study was to determine the influence of dose reduction on a commercially available lung cancer prediction convolutional neuronal network (LCP-CNN). METHODS: CT scans from a cohort provided by the local lung cancer center (n = 218) with confirmed pulmonary malignancies and their corresponding reduced dose simulations (25% and 5% dose) were subjected to the LCP-CNN. The resulting LCP scores (scale 1-10, increasing malignancy risk) and the proportion of correctly classified nodules were compared. The cohort was divided into a low-, medium-, and high-risk group based on the respective LCP scores; shifts between the groups were studied to evaluate the potential impact on nodule management. Two different malignancy risk score thresholds were analyzed: a higher threshold of ≥ 9 ("rule-in" approach) and a lower threshold of > 4 ("rule-out" approach). RESULTS: In total, 169 patients with 196 nodules could be included (mean age ± SD, 64.5 ± 9.2 year; 49% females). Mean LCP scores for original, 25% and 5% dose levels were 8.5 ± 1.7, 8.4 ± 1.7 (p > 0.05 vs. original dose) and 8.2 ± 1.9 (p < 0.05 vs. original dose), respectively. The proportion of correctly classified nodules with the "rule-in" approach decreased with simulated dose reduction from 58.2 to 56.1% (p = 0.34) and to 52.0% for the respective dose levels (p = 0.01). For the "rule-out" approach the respective values were 95.9%, 96.4%, and 94.4% (p = 0.12). When reducing the original dose to 25%/5%, eight/twenty-two nodules shifted to a lower, five/seven nodules to a higher malignancy risk group. CONCLUSION: CT dose reduction may affect the analyzed LCP-CNN regarding the classification of pulmonary malignancies and potentially alter pulmonary nodule management. CLINICAL RELEVANCE STATEMENT: Utilization of a "rule-out" approach with a lower malignancy risk threshold prevents underestimation of the nodule malignancy risk for the analyzed software, especially in high-risk cohorts. KEY POINTS: • LCP-CNN may be affected by CT image parameters such as noise resulting from low-dose CT acquisitions. • CT dose reduction can alter pulmonary nodule management recommendations by affecting the outcome of the LCP-CNN. • Utilization of a lower malignancy risk threshold prevents underestimation of pulmonary malignancies in high-risk cohorts.

6.
Eur J Pediatr ; 182(7): 3113-3120, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37093305

RESUMO

Correct management of infants after minor head trauma is crucial to minimize the risk to miss clinically important traumatic brain injury (ciTBI). Current practices typically involve CT or in-hospital surveillance. Cranial ultrasound (CUS) provides a radiation-free and fast alternative. This study examines the accuracy of radiologist-performed CUS to detect skull fracture (SF) and/or intracranial hemorrhage (ICH). An inconspicuous CUS followed by an uneventful clinical course would allow exclusion of ciTBI with a great certainty. This monocentric, retrospective, observational study analyzed CUS in infants (< 12 months) after minor head trauma at Bern University Children's Hospital, between 7/2013 and 8/2020. The primary outcome was the sensitivity and specificity of CUS in detecting SF and/or ICH by comparison to the clinical course and to additional neuroimaging. Out of a total of 325 patients, 73% (n = 241) had a normal CUS, 17% (n = 54) were found with SF, and ICH was diagnosed in 2.2% patients (n = 7). Two patients needed neurosurgery and three patients deteriorated clinically during surveillance. Additional imaging was performed in 35 patients. The sensitivity of CUS was 93% ([0.83, 0.97] 95% CI) and the specificity 98% ([0.95, 0.99] 95% CI). All false-negative cases originated in missed SF without clinical deterioration; no ICH was missed.  Conclusion: This study shows high accuracy of CUS in exclusion of SF and ICH, which can cause ciTBI. Therefore, CUS offers a reliable method of neuroimaging in infants after minor head trauma and gives reassurance to reduce the duration of in-hospital surveillance. What is Known: • Minor head trauma can cause clinically important traumatic brain injury in infants, and the management of these cases is a challenge for the treating physician. • Cranial ultrasound (CUS) is regularly used in neonatology, but its accuracy after head trauma in infants is controversial. What is New: • CUS performed by a trained radiologist can exclude findings related to clinically important traumatic brain injury (ciTBI) with high sensitivity and specificity. It therefore offers reassurance in the management of infants after minor head trauma.


Assuntos
Lesões Encefálicas Traumáticas , Traumatismos Craniocerebrais , Criança , Humanos , Lactente , Estudos Retrospectivos , Traumatismos Craniocerebrais/diagnóstico por imagem , Sensibilidade e Especificidade , Hemorragias Intracranianas , Progressão da Doença
7.
Invest Radiol ; 58(8): 602-609, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37058321

RESUMO

ABSTRACT: Interstitial lung disease (ILD) is now diagnosed by an ILD-board consisting of radiologists, pulmonologists, and pathologists. They discuss the combination of computed tomography (CT) images, pulmonary function tests, demographic information, and histology and then agree on one of the 200 ILD diagnoses. Recent approaches employ computer-aided diagnostic tools to improve detection of disease, monitoring, and accurate prognostication. Methods based on artificial intelligence (AI) may be used in computational medicine, especially in image-based specialties such as radiology. This review summarises and highlights the strengths and weaknesses of the latest and most significant published methods that could lead to a holistic system for ILD diagnosis. We explore current AI methods and the data use to predict the prognosis and progression of ILDs. It is then essential to highlight the data that holds the most information related to risk factors for progression, e.g., CT scans and pulmonary function tests. This review aims to identify potential gaps, highlight areas that require further research, and identify the methods that could be combined to yield more promising results in future studies.


Assuntos
Inteligência Artificial , Doenças Pulmonares Intersticiais , Humanos , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Prognóstico , Tomografia Computadorizada por Raios X/métodos , Radiologistas , Pulmão/diagnóstico por imagem
9.
Rofo ; 195(1): 47-54, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36067777

RESUMO

Despite current recommendations, there is no recent scientific study comparing the influence of CT reconstruction kernels on lung pattern recognition in interstitial lung disease (ILD).To evaluate the sensitivity of lung (i70) and soft (i30) CT kernel algorithms for the diagnosis of ILD patterns.We retrospectively extracted between 15-25 pattern annotations per case (1 annotation = 15 slices of 1 mm) from 23 subjects resulting in 408 annotation stacks per lung kernel and soft kernel reconstructions. Two subspecialized chest radiologists defined the ground truth in consensus. 4 residents, 2 fellows, and 2 general consultants in radiology with 3 to 13 years of experience in chest imaging performed a blinded readout. In order to account for data clustering, a generalized linear mixed model (GLMM) with random intercept for reader and nested for patient and image and a kernel/experience interaction term was used to analyze the results.The results of the GLMM indicated, that the odds of correct pattern recognition is 12 % lower with lung kernel compared to soft kernel; however, this was not statistically significant (OR 0.88; 95%-CI, 0.73-1.06; p = 0.187). Furthermore, the consultants' odds of correct pattern recognition was 78 % higher than the residents' odds, although this finding did not reach statistical significance either (OR 1.78; 95%-CI, 0.62-5.06; p = 0.283). There was no significant interaction between the two fixed terms kernel and experience. Intra-rater agreement between lung and soft kernel was substantial (κ = 0.63 ±â€Š0.19). The mean inter-rater agreement for lung/soft kernel was κ = 0.37 ±â€Š0.17/κ = 0.38 ±â€Š0.17.There is no significant difference between lung and soft kernel reconstructed CT images for the correct pattern recognition in ILD. There are non-significant trends indicating that the use of soft kernels and a higher level of experience lead to a higher probability of correct pattern identification. · There is no significant difference between lung and soft kernel reconstructed CT images for the correct pattern recognition in interstitial lung disease.. · There are even non-significant tendencies that the use of soft kernels lead to a higher probability of correct pattern identification.. · These results challenge the current recommendations and the routinely performed separate lung kernel reconstructions for lung parenchyma analysis.. CITATION FORMAT: · Klaus JB, Christodoulidis S, Peters AA et al. Influence of Lung Reconstruction Algorithms on Interstitial Lung Pattern Recognition on CT. Fortschr Röntgenstr 2023; 195: 47 - 54.


Assuntos
Pulmão , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Pulmão/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Algoritmos
10.
North Clin Istanb ; 9(4): 414-418, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36276575

RESUMO

Magnetic resonance imaging (MRI) is a technique useful for the diagnosis of cartilage damage due to high sensitivity to identify subchondral bone abnormalities and full-thickness cartilage lesions. The lack of a study on knee cartilage changes over time in patients with osteoarthritis (OA) by MRI technique led us to investigate the accuracy of MRI in identifying knee cartilage changes over time in patients with OA in a systematic review. In the present systematic review, started from the beginning of 2020 in one of the University Hospitals in Iran, the databases of CINAHL, Ovid, Elsevier, Scopus, PubMed, Science Direct, and Web of Science were searched using the keywords MRI, OA, Cartilage Lesion, Imaging Techniques. A total of 169 articles were retrieved in the initial search, and after reviewing the titles, abstracts, and full-texts, finally, seven were enrolled in the systematic review. Review of the selected papers showed that a total of 1091 subjects were studied, of which 355 were males. The results of all the studies, except one, indicated the high accuracy of MRI to identify knee cartilage changes over time. MRI technique can show cartilage changes with high accuracy in patients with knee OA over time. We proved the potential of MRI to identify articular cartilage injuries in patients with OA and its importance to the evaluation of articular cartilage lesions along with other available techniques.

11.
Swiss Med Wkly ; 152(15-16)2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35633633

RESUMO

BACKGROUND: Lung cancer is the leading cause of cancer-related deaths in Switzerland. Despite this, there is no lung cancer screening program in the country. In the United States, low-dose computed tomography (LDCT) lung cancer screening is partially established and endorsed by guidelines. Moreover, evidence is growing that screening reduces lung cancer-related mortality and this was recently shown in a large European randomized controlled trial. Implementation of a lung cancer screening program, however, is challenging and depends on many country-specific factors. The goal of this article is to outline a potential Swiss lung cancer screening program. FRAMEWORK: An exhaustive literature review on international screening models as well as interviews and site visits with international experts were initiated. Furthermore, workshops and interviews with national experts and stakeholders were conducted to share experiences and to establish the basis for a national Swiss lung cancer screening program. SCREENING APPROACH: General practitioners, pulmonologists and the media should be part of the recruitment process. Decentralisation of the screening might lead to a higher adherence rate. To reduce stigmatisation, the screening should be integrated in a "lung health check". Standardisation and a common quality level are mandatory. The PLCOm2012 risk calculation model with a threshold of 1.5% risk for developing cancer in the next six years should be used in addition to established inclusion criteria. Biennial screening is preferred. LUNG RADS and NELSON+ are applied as classification models for lung nodules. CONCLUSION: Based on data from recent studies, literature research, a health technology assessment, the information gained from this project and a pilot study the Swiss Interest Group for lung cancer screening (CH-LSIG) recommends the timely introduction of a systematic lung cancer screening program in Switzerland. The final decision is for the Swiss Cancer Screening Committee to make.


Assuntos
Detecção Precoce de Câncer , Neoplasias Pulmonares , Detecção Precoce de Câncer/métodos , Estudos de Viabilidade , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Projetos Piloto , Suíça , Tomografia Computadorizada por Raios X/métodos
12.
Melanoma Res ; 32(4): 211-217, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35579669

RESUMO

Locoregional and distant metastases account for most cases of morbidity and mortality associated with melanoma. In addition, local recurrences of melanoma might be the onset of disseminated disease. Therefore, precise diagnosis and therapy are warranted to minimize morbidity and increase survival in a subset of patients. However, the correct distribution of the metastatic lesions on the skin is often difficult to estimate. We present the application of noncontrast-enhanced 3-Tesla MRI using surface coil to detect locoregional cutaneous metastases of malignant melanoma on the basis of the topographic assessment of skin lesions. Furthermore, in a systematic review, we summarize the current knowledge about application of MRI in assessment of location, distribution, and depth of cutaneous primary malignant melanoma. MRI might be applied to evaluate the location, distribution, size, and depth of the locoregional cutaneous metastasis of malignant melanoma to identify the optimal cost-effective treatment strategies and monitor their effects.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Imageamento por Ressonância Magnética , Melanoma/patologia , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/secundário , Melanoma Maligno Cutâneo
13.
Radiology ; 304(1): 195-204, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35380498

RESUMO

Background Evidence regarding short-term effects of electronic nicotine delivery systems (ENDS) and tobacco smoke on lung ventilation and perfusion is limited. Purpose To examine the immediate effect of ENDS exposure and tobacco smoke on lung ventilation and perfusion by functional MRI and lung function tests. Materials and Methods This prospective observational pilot study was conducted from November 2019 to September 2021 (substudy of randomized controlled trial NCT03589989). Included were 44 healthy adult participants (10 control participants, nine former tobacco smokers, 13 ENDS users, and 12 active tobacco smokers; mean age, 41 years ± 12 [SD]; 28 men) who underwent noncontrast-enhanced matrix pencil MRI and lung function tests before and immediately after the exposure to ENDS products or tobacco smoke. Baseline measurements were acquired after 2 hours of substance abstinence. Postexposure measurements were performed immediately after the exposure. MRI showed semiquantitative measured impairment of lung perfusion (RQ) and fractional ventilation (RFV) impairment as percentages of affected lung volume. Lung clearance index (LCI) was assessed by nitrogen multiple-breath washout to capture ventilation inhomogeneity and spirometry to assess airflow limitation. Absolute differences were calculated with paired Wilcoxon signed-rank test and differences between groups with unpaired Mann-Whitney test. Healthy control participants underwent two consecutive MRI measurements to assess MRI reproducibility. Results MRI was performed and lung function measurement was acquired in tobacco smokers and ENDS users before and after exposure. MRI showed a decrease of perfusion after exposure (RQ, 8.6% [IQR, 7.2%-10.0%] to 9.1% [IQR, 7.8%-10.7%]; P = .03) and no systematic change in RFV (P = .31) among tobacco smokers. Perfusion increased in participants who used ENDS after exposure (RQ, 9.7% [IQR, 7.1%-10.9%] to 9.0% [IQR, 6.9%-10.0%]; P = .01). RFV did not change (P = .38). Only in tobacco smokers was LCI elevated after smoking (P = .02). Spirometry indexes did not change in any participants. Conclusion MRI showed a decrease of lung perfusion after exposure to tobacco smoke and an increase of lung perfusion after use of electronic nicotine delivery systems. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Kligerman in this issue.


Assuntos
Poluição por Fumaça de Tabaco , Vaping , Adulto , Humanos , Pulmão/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Masculino , Perfusão , Estudos Prospectivos , Reprodutibilidade dos Testes , Fumar/efeitos adversos , Vaping/efeitos adversos
14.
Eur Radiol ; 32(6): 4324-4332, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35059804

RESUMO

OBJECTIVES: This study was conducted to evaluate the effect of dose reduction on the performance of a deep learning (DL)-based computer-aided diagnosis (CAD) system regarding pulmonary nodule detection in a virtual screening scenario. METHODS: Sixty-eight anthropomorphic chest phantoms were equipped with 329 nodules (150 ground glass, 179 solid) with four sizes (5 mm, 8 mm, 10 mm, 12 mm) and scanned with nine tube voltage/current combinations. The examinations were analyzed by a commercially available DL-based CAD system. The results were compared by a comparison of proportions. Logistic regression was performed to evaluate the impact of tube voltage, tube current, nodule size, nodule density, and nodule location. RESULTS: The combination with the lowest effective dose (E) and unimpaired detection rate was 80 kV/50 mAs (sensitivity: 97.9%, mean false-positive rate (FPR): 1.9, mean CTDIvol: 1.2 ± 0.4 mGy, mean E: 0.66 mSv). Logistic regression revealed that tube voltage and current had the greatest impact on the detection rate, while nodule size and density had no significant influence. CONCLUSIONS: The optimal tube voltage/current combination proposed in this study (80 kV/50 mAs) is comparable to the proposed combinations in similar studies, which mostly dealt with conventional CAD software. Modification of tube voltage and tube current has a significant impact on the performance of DL-based CAD software in pulmonary nodule detection regardless of their size and composition. KEY POINTS: • Modification of tube voltage and tube current has a significant impact on the performance of deep learning-based CAD software. • Nodule size and composition have no significant impact on the software's performance. • The optimal tube voltage/current combination for the examined software is 80 kV/50 mAs.


Assuntos
Aprendizado Profundo , Neoplasias Pulmonares , Nódulo Pulmonar Solitário , Algoritmos , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Sensibilidade e Especificidade , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
15.
Acta Radiol ; 63(1): 35-41, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33356359

RESUMO

BACKGROUND: Percutaneous needle biopsy of the lung (PCBL) under image guidance has become a safe and effective minimal invasive method to obtain a specimen related histological diagnosis of pulmonary lesions. PURPOSE: To evaluate the diagnostic yield and safety of two different coaxial biopsy technologies: full core and notch sampling technology. The former allowing the removal of full punch cylinders and the latter using a cutting-edge mechanism. MATERIAL AND METHODS: A retrospective analysis of 48 consecutive PCBL procedures has been carried out for this prognostic study, involving patients with a documented pulmonary nodule or mass lesion on previous computed tomography (CT) scans. The study population included 38 men and 10 women (mean age = 67 years). Of these 48 patients who underwent a procedure with a co-axial cutting system, 24 have been performed with notch sampling technology and 24 with full core technology. RESULTS: Out of the 48 biopsy procedures, 46 yielded specimens were adequate for histopathological evaluation, consistent with a technical success rate of 96%. The most common induced image-guided biopsy complication was a pneumothorax, occurring in 14 patients (35%). Seven patients with a pneumothorax were attributed to the full core technology and seven to the notch sampling technology (odds ratio = 1, 95% confidence interval = 0.28-3.51, P = 1). CONCLUSION: In the setting of full core versus notch sampling percutaneous CT-guided coaxial needle biopsy of the lung, no significant difference in the diagnostic accuracy and the incidence of pneumothoraces could be shown, while both technologies have an excellent diagnostic performance.


Assuntos
Biópsia Guiada por Imagem/métodos , Pneumopatias/patologia , Pneumotórax/etiologia , Tomografia Computadorizada por Raios X , Idoso , Biópsia com Agulha de Grande Calibre/efeitos adversos , Feminino , Humanos , Biópsia Guiada por Imagem/efeitos adversos , Pneumopatias/diagnóstico por imagem , Masculino , Prognóstico , Estudos Retrospectivos
16.
Rofo ; 194(4): 391-399, 2022 Apr.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-34687027

RESUMO

OBJECTIVE: The aim of the study was to use a software application to analyze the examination times and changeover times of two clinically highly applied MRI scanners at a university hospital for radiology and to evaluate whether this could result in optimization potential for examination planning in the daily clinical routine of MRI diagnostics. MATERIALS AND METHODS: Based on the newly developed software application "Teamplay Usage" (Siemens Healthineers, Germany), the examinations carried out on two MRI scanners (1.5 T and 3 T) were investigated within an analysis period of 12 months with regard to the type of examination and its duration. In addition, compliance with the previously defined planning time (30, 45, 60 min.) was checked and deviations were analyzed. In addition, the changeover times between the examinations were determined and a possible influence due to the exchange of MRI coils was investigated for a selection of change combinations. RESULTS: For the total of 7184 (1.5 T: 3740; 3 T: 3444) examinations included in the study, the median examination time was 43:02 minutes (1.5 T: 43:17 min.; 3 T: 42:45 min.). The ten most frequent types of examinations per MRI scanner were completed within the predefined plan time of 54.5 % (1.5 T) and 51.9 % (3 T), taking into account a previously defined preparation and post-processing time of 9 minutes per examination. Overall, more time was spent on examinations with a planned time of 30 minutes, whereas the majority of the examinations planned with 45 minutes were also completed within this time. Examinations with a planned time of 60 minutes usually took less time. A comparison between the planned time and the determined examination duration of the most common types of examinations showed overall a slight potential for optimization. Coil exchanges between two examinations had a small, but statistically not significant effect on the median changeover time (p = 0.062). CONCLUSION: Utilizing a software-based analysis, a detailed overview of the type of examination, examination duration, and changeover times of frequently used clinical MRI scanners could be obtained. In the clinic examined, there was little potential for optimization of examination planning. An exchange of MRI coils necessary for different types of examination only had a small effect on the changeover times. KEY POINTS: · The use of the "Teamplay Usage" software application enables a comprehensive overview of the type of examination, examination duration, and changeover times for MRI scanners.. · Adjustments to examination planning for MRI diagnostics show optimization potential, which, however, is to be assessed as low in the clinic examined.. · Necessary replacements of MRI coils only have a small effect on the changeover times.. CITATION FORMAT: · Meyl TP, Berghöfer A, Blatter T et al. Software-Based Evaluation of Optimization Potential for Clinical MRI Scanners in Radiology. Fortschr Röntgenstr 2022; 194: 391 - 399.


Assuntos
Imageamento por Ressonância Magnética , Radiologia , Hospitais Universitários , Humanos , Radiografia , Software
17.
Acta Clin Belg ; 77(4): 785-786, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34556010

RESUMO

Following intravenous contrast medium (CM) injection, a small proportion of patients acquires hypersensitivity reactions that occur either immediately or non-immediately (delayed). Although it is now claer that even oral applied CMs are able to cause adverse reactions, many radiologists as well as physicians of other disciplines, still believe that CM-application via the gastrointestinal route does not induce hypersensitivity reactions. Since this kind of misinterpretation may harm the patient, education on this topic is still necessary. Therefore, we describe a case who acquired a delayed hypersensitivity reaction following the oral intake of a non-ionic iodinated CM.


Assuntos
Hipersensibilidade a Drogas , Hipersensibilidade Tardia , Hipersensibilidade Imediata , Meios de Contraste/efeitos adversos , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/etiologia , Humanos , Hipersensibilidade Tardia/induzido quimicamente , Hipersensibilidade Tardia/complicações , Hipersensibilidade Tardia/diagnóstico , Hipersensibilidade Imediata/induzido quimicamente , Hipersensibilidade Imediata/complicações , Hipersensibilidade Imediata/diagnóstico
18.
Invest Radiol ; 57(1): 1-12, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34510100

RESUMO

ABSTRACT: This review provides a balanced perspective regarding the clinical utility of magnetic resonance systems across the range of field strengths for which current state-of-the-art units exist (0.55 T, 1.5 T, 3 T, and 7 T). Guidance regarding this issue is critical to appropriate purchasing, usage, and further dissemination of this important imaging modality, both in the industrial world and in developing nations. The review serves to provide an important update, although to a large extent this information has never previously been openly presented. In that sense, it serves also as a position paper, with statements and recommendations as appropriate.


Assuntos
Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
19.
Acta Radiol ; 63(5): 632-641, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34056917

RESUMO

X-ray contrast media have been reported to have inhibitory effects on bacterial growth. Despite its potentially beneficial effect on patients, these features of contrast media have received relatively little attention in the medical literature in the past decades. The aim of this review is to evaluate the literature concerning the bactericidal and bacteriostatic effects of X-ray contrast media, specifically if there is a known difference concerning these effects between ionic and non-ionic contrast media. Systematic literature review was performed for the years of publication between 1911 and 2019. Since the publication of Grossich in 1911, the effect of iodine on the treatment of superficial infections in surgical procedures has been established clinical knowledge. Bacteriostatic and bactericidal effects of ionic X-ray contrast media are well established. However, non-ionic contrast agents have been the subject of little research in this respect. In past decades, the hypothesis emerged in the literature that mainly the concentration of free iodine might be responsible for any bacteriostatic or bactericidal effect of ionic X-ray contrast media. Nowadays, however, only non-ionic contrast media are used. The question regarding the mechanism and magnitude of bacteriostatic or bactericidal effects of these, non-ionic contrast media, could not be answered conclusively from this review. Non-ionic contrast media could be used intentionally when a local antibacterial effect is intended (e.g. in percutaneous abscess drainage), as well as to reduce the overall dose of antibiotics administered to a patient. Thus, this question remains relevant and might constitute the area of future research.


Assuntos
Meios de Contraste , Iodo , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Meios de Contraste/efeitos adversos , Humanos , Iodo/farmacologia , Raios X
20.
J Endocr Soc ; 5(8): bvab082, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34268461

RESUMO

Obstructive sleep apnea (OSA), independently of obesity (OBS), predisposes to insulin resistance (IR) for largely unknown reasons. Because OSA-related intermittent hypoxia triggers lipolysis, overnight increases in circulating free fatty acids (FFAs) including palmitic acid (PA) may lead to ectopic intramuscular lipid accumulation potentially contributing to IR. Using 3-T-1H-magnetic resonance spectroscopy, we therefore compared intramyocellular and extramyocellular lipid (IMCL and EMCL) in the vastus lateralis muscle at approximately 7 am between 26 male patients with moderate-to-severe OSA (17 obese, 9 nonobese) and 23 healthy male controls (12 obese, 11 nonobese). Fiber type composition was evaluated by muscle biopsies. Moreover, we measured fasted FFAs including PA, glycated hemoglobin A1c, thigh subcutaneous fat volume (ScFAT, 1.5-T magnetic resonance tomography), and maximal oxygen uptake (VO2max). Fourteen patients were reassessed after continuous positive airway pressure (CPAP) therapy. Total FFAs and PA were significantly (by 178% and 166%) higher in OSA patients vs controls and correlated with the apnea-hypopnea index (AHI) (r ≥ 0.45, P < .01). Moreover, IMCL and EMCL were 55% (P < .05) and 40% (P < .05) higher in OSA patients, that is, 114% and 103% in nonobese, 24.4% and 8.4% in obese participants (with higher control levels). Overall, PA, FFAs (minus PA), and ScFAT significantly contributed to IMCL (multiple r = 0.568, P = .002). CPAP significantly decreased EMCL (-26%) and, by trend only, IMCL, total FFAs, and PA. Muscle fiber composition was unaffected by OSA or CPAP. Increases in IMCL and EMCL are detectable at approximately 7 am in OSA patients and are partly attributable to overnight FFA excesses and high ScFAT or body mass index. CPAP decreases FFAs and IMCL by trend but significantly reduces EMCL.

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