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2.
J Belg Soc Radiol ; 100(1): 8, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-30151438

RESUMO

A preterm neonate was born in our center, as a part of a diamniotic dichorionic twin pregnancy, complicated with placental abruption with need for urgent cesarean section at 26 weeks of gestation. After a difficult neonatal start with respiratory and cardiovascular problems, the neonate safely reached the neonatal intensive care unit. Further work-up and supportive care was continued. Transcranial ultrasound imaging through the anterior fontanel was part of this work-up. Initial examinations were not normal, and showed cystic lesions along the germinal matrix, without hydrocephalus or parenchymal lesions. The findings were highly suggestive of sequellae of grade II germinal matrix bleed according to Papile and Burstein (Image A). Further follow-up examinations by means of ultrasound depicted a discrete enlargement of the lateral ventricles over time (Image B). Later on development of widespread periventricular cystic lesions became apparent (Image C and D). The cystic lesions are located in the periventricular white matter, and are not attached to the ventricles. This finding makes cystic periventricular leukomalacia the preferred diagnosis, and makes venous infarction with cystic alterations secondary to germinal matrix bleeding less likely.

4.
Eur Radiol ; 23(9): 2441-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23673573

RESUMO

OBJECTIVES: To compare the diagnostic performance of single-view breast tomosynthesis (BT) with that of dual-view mammography (MX); to assess the benefit of adding the craniocaudal (CC) mammographic view to BT, and of adding BT to MX plus breast ultrasound, considered to be the reference work-up. METHODS: One hundred and fifty-five consenting patients with unresolved mammographic and/or ultrasound findings or breast symptoms underwent conventional work-up plus mediolateral oblique-view BT of the affected breast. The final study set in 130 patients resulted in 55 malignant and 76 benign and normal cases. Seven breast radiologists rated the cases through five sequential techniques using a BIRADS-based scale: MX, MX + ultrasound, MX + ultrasound + BT, BT, BT + MX(CC). Multireader, multicase receiver operating characteristic (ROC) analysis was performed and performance of the techniques was assessed from the areas under ROC curves. The performance of BT and of BT + MX(CC) was tested versus MX; the performance of MX + ultrasound + BT tested versus MX + ultrasound. RESULTS: Tomosynthesis was found to be non-inferior to mammography. BT + MX(CC) did not appear to be superior to MX, and MX + ultrasound + BT not superior to MX + ultrasound. CONCLUSIONS: Overall, none of the five techniques tested outperformed the others. Further clinical studies are needed to clarify the role of BT as a substitute for traditional work-up in the diagnostic environment. KEY POINTS: • Digital breast tomosynthesis is a new adjunct to mammography and breast ultrasound. • We compared the diagnostic performance of these investigations in an experimental observer study. • Single-view breast tomosynthesis was confirmed as non-inferior to dual-view mammography. • None of the investigations (or combinations) tested outperformed the others. • Further prospective studies are needed to clarify precise role of tomosynthesis for diagnostic application.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imageamento Tridimensional/métodos , Mamografia/métodos , Ultrassonografia Mamária/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Mama/patologia , Feminino , Humanos , Mamografia/instrumentação , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia Mamária/instrumentação
5.
AJR Am J Roentgenol ; 195(1): 161-7, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20566811

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the diagnostic performance of digital tomosynthesis in comparison with digital radiography in the detection of urinary stones with MDCT as the reference standard. SUBJECTS AND METHODS: Fifty consecutively enrolled patients (32 men, 18 women; mean age, 51.5 years; range, 19-83 years) referred for unenhanced MDCT of the abdomen with suspicion of urinary stones also underwent digital tomosynthesis and digital radiography (anteroposterior and bladder inlet views). Images from all examinations were randomly read by three blinded radiologists. The mean effective doses for digital tomosynthesis, digital radiography, and low- and high-dose MDCT were measured on a male phantom. Free-response receiver operating characteristics and receiver operating characteristics analyses were used to compare the diagnostic performance of digital radiography with that of digital tomosynthesis. RESULTS: Both types of analysis showed significantly better performance of tomosynthesis over digital radiography for all urinary stones (p < 0.05). No such improvement was found for ureteral stones. The gain in sensitivity with tomosynthesis was largest for stones between 2 and 5 mm in diameter. The mean effective dose was 0.5 mSv for digital radiography, 0.85 mSv for tomosynthesis, 2.5 mSv for low-dose MDCT, and 12.6 mSv for high-dose MDCT. CONCLUSION: Use of digital tomosynthesis of the abdomen results in improved detection of urinary stones in general over digital radiography with only a slight increase in effective dose. Use of tomosynthesis, however, was not associated with major improvement in the diagnosis of ureteral stones. The technique has potential as an alternative imaging technique in the detection and follow-up of urinary stones.


Assuntos
Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada Espiral/métodos , Urolitíase/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Posicionamento do Paciente , Imagens de Fantasmas , Estudos Prospectivos , Curva ROC , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Software
7.
Eur J Radiol ; 69(1): 131-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17950553

RESUMO

PURPOSE: To assess the added value of true diffusion (D), perfusion factor (f) and apparent diffusion coefficient at low b-values (ADC(low)) for differentiation between liver metastases and hemangiomas based on respiratory-triggered high-resolution Black-Blood Single-Shot SpinEcho Echo Planar Imaging (BB SS SE-EPI). MATERIALS AND METHODS: Twenty-five patients suspected for malignant colorectal liver lesions were included in this study. A total of 106 lesions were examined. Different b-value images were compared for lesion conspicuity, image quality and artifacts using rank order statistic (RIDIT) and Student's t-test. D, f, and ADC(low) values were calculated. Pearson correlation coefficient is used for comparison of interobserver variability. RESULTS: Best lesion conspicuity (p<0.05) was achieved with BB SS SE-EPI (b=0 and 10s/mm(2)); best image quality (p<0.05) with b=10s/mm(2). Image artifacts were lowest (p<0.05) with b=0s/mm(2). Over the whole sample, D in metastases (D(met)) was significantly (p<0.05) lower than D in hemangiomas (D(hem)); f and ADC(low) of metastases (f(met), respectively, ADC(lowmet)) were significantly (p<0.05) higher than f and ADC(low) of hemangiomas (f(hem), respectively, ADC(lowhem)). All Pearson correlations were statistically significant at a 0.01 level. CONCLUSIONS: This preliminary study shows the potential of BB SS SE-EPI as a useful technique to aid in differentiating between liver metastasis and hemangioma. The calculation of D, f and ADC(low) provides useful additional information for differentiating metastases from hemangiomas.


Assuntos
Neoplasias Colorretais/patologia , Imagem Ecoplanar/métodos , Hemangioma/patologia , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Necrose/patologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Skeletal Radiol ; 37(6): 569-72, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18343919

RESUMO

Digital tomosynthesis is a relatively new technique for producing an arbitrary number of slice images generated retrospectively from a sequence of projections acquired during a single motion of the X-ray tube. Tomosynthesis has already been described for mammographic and thoracic applications to reduce overlap of tissues. We present a case ofa 19-year-old man with a suspected scaphoid fracture in which we used digital tomosynthesis to confirm the diagnosis and thus excluded the need for other imaging modalities. We also describe the technique and background of tomosynthesis with possible future indications for this new promising technique.


Assuntos
Fraturas Ósseas/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Osso Escafoide/lesões , Tomografia por Raios X/métodos , Adulto , Humanos , Masculino
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