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1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20043117

RESUMO

BackgroundChest CT had high sensitivity in diagnosing novel coronavirus pneumonia (NCP) at early stage, giving it an advantage over nucleic acid detection in time of crisis. Deep learning was reported to discover intricate structures from clinical images and achieve expert-level performance in medical image analysis. To develop and validate an integrated deep learning framework on chest CT images for auto-detection of NCP, particularly focusing on differentiating NCP from influenza pneumonia (IP). Methods35 confirmed NCP cases were consecutively enrolled as training set from 1138 suspected patients in three NCP designated hospitals together with 361 confirmed viral pneumonia patients from center one including 156 IP patients, from May, 2015 to February, 2020. The external validation set enrolled 57 NCP patients and 50 IP patients from eight centers. Results96.6% of NCP lesions were larger than 1 cm and 76.8% were with intensity below -500 Hu, indicating less consolidation than IP lesions which had nodules ranging 5-10 mm. The classification schemes accurately distinguished NCP and IP lesions with area under the receiver operating characteristic curve (AUC) above 0.93. The Trinary scheme was more device-independent and consistent with specialists than the Plain scheme, which achieved a F1 score of 0.847, higher than the Plain scheme (0.774), specialists (0.785) and residents (0.644). ConclusionsOur study potentially provides an accurate early diagnosis tool on chest CT for NCP with high transferability, and shows high efficiency in differentiating NCP and IP, helping to reduce misdiagnosis and contain the pandemic transmission.

2.
Chinese Journal of Radiology ; (12): 671-676, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-868330

RESUMO

Objective:To explore the optimal keV for the visualization of rectal cancer and to investigate its diagnostic performance in the preoperative T staging of rectal cancer using virtual monoenergetic image (VMI) on a novel dual-layer spectral detector CT.Methods:Totally 43 patients with pathologically confirmed rectal cancer were involved in this retrospective study in Ruijin Hospital, Shanghai Jiao Tong University School of Medicine from May to October 2019. All the patients underwent novel dual-layer spectral detector CT scanning within 1 week before surgery. The 40, 50, 60, 70 keV VMI and 120 kVp conventional polyenergetic image (PI) were reconstructed based on the venous phase imagings. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the rectal cancer were measured and the image quality was scored using a 5-point scale to obtain the best keV VMI. Taking pathological results as golden standard, the accuracy rate of T staging was calculated and compared between the best keV VMI and 120 kVp PI. The CT attenuation, SNR and CNR were compared with one-way ANOVA analysis among the 5 groups of images.Image quality scores were assessed with Friedman test,and the accuracy rate was compared by McNemar test or Fisher exact test.Results:The SNR and CNR of rectal cancer at 40-70 keV VMI was better than 120 kVp PI ( P<0.05), the SNR at 40 keV VMI was the highest among all the VMI ( P<0.05), the CNR at 40 keV VMI was better, but there was no significant difference between 40 and 50 keV VMI ( P>0.05). The image scores at 40-60 keV VMI were all significantly superior to those of the 120 kVp PI ( P<0.001). 40 keV VMI was the best image. The accuracy rate of 40 keV VMI (67.4%, 29/43) was higher than that of 120 kVp PI (48.8%, 21/43) in the T stage ( P=0.008). The 40 keV VMI had a higher diagnostic accuracy rate (83.7%, 36/43) and specificity (58.8%, 10/17) in diagnosis of locally advanced rectal cancer (T3-4, P=0.016, 0.031). Conclusion:The image quality of novel dual-layer spectral detector CT at 40 keV VMI is good, which can improve the accuracy rate of preoperative T staging of rectal cancer.

3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-274153

RESUMO

<p><b>OBJECTIVE</b>To evaluate the CT features of radiation-induced jaw osteosarcoma(RIJOS) developed after therapeutic irradiation for a variety of nonosseous lesions.</p><p><b>METHODS</b>The demographic and CT findings of thirteen patients with RIJOS were reviewed retrospectively.Observation items included location, bone destruction, mineralized tumor matrix, periosteal reaction, soft tissue extension and calcification.Of the thirteen patients, twelve were male and one was female. The mean age was 48 years (range: 29-68 years).Five patients had tumors in the maxilla and eight in the mandible. All the patients underwent tumor resection.</p><p><b>RESULTS</b>The latent period before development of RIJOS ranged from 3.5 to 14 years (mean, 11 years).In all thirteen patients, eight tumors were osteoblastic, with one osteolytic and four mixed lesions.Osteoid tumor matrix mineralization was present in twelve patients. Periosteal reaction was identified in 11 cases.Soft-tissue extension was present in all patients beyond the area of bone destruction.</p><p><b>CONCLUSIONS</b>The characteristic CT imaging of RIJOS showed the bone destruction associated with a large number of mineralized tumor matrix and significant soft tissue extension in the original radiation field after radiotherapy. CT findings could play an important role in identifying the tumor and pre-operative assessment.</p>


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Ósseas , Diagnóstico por Imagem , Calcificação Fisiológica , Mandíbula , Neoplasias Induzidas por Radiação , Diagnóstico por Imagem , Osteossarcoma , Diagnóstico por Imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
4.
Journal of Practical Radiology ; (12): 588-592, 2014.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-446953

RESUMO

Objective To compare the image quality and radiation dose of prospective electrocardiogram(ECG)-triggered high-pitch spiral scan,prospectively triggered sequential scan and retrospectively triggered spiral scanning mode by dual-source CT in the follow-up of coronary artery bypass graft(CABG).Methods Totally 90 patients with stable heart rate(≤65 beats per minute)after bypass surgery were randomized to undergo prospective high-pitch spiral scan in group A (n=30),prospective sequential scan in group B (n=30),and retrospective spiral scan in group C (n=30).The patency and image quality of the grafts were blindly evalua-ted by two independent readers.Moreover,radiation dose of the three modes were evaluated.Results Scanning time of group A was significantly shorter than that of group B and group C (P<0.05).The average image quality score had no significant difference among three groups(H=0.449,P=0.799).The effective radiation dose of group A,group B and group C were (2.64±1.21)mSv, (6.48±2.58)mSv and(18.95±7.16)mSv,which was significantly lower in group A(H=101.21,P=0.00).Conclusion In pa-tients with a stable HR of 65 beats per minute or less,high-pitch spiral CT scan provides similar image quality at lower radiation dose compared with sequential scan and retrospective spiral scan,which can be widely used as a non-invasive effective tool for the post-operative follow-up of CABG.

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-264229

RESUMO

This paper describes the design process and implementation process of electronic film system. The establishment of electronic film system allowed us to aggressively reduce film use and costs and to demonstrate a positive return.


Assuntos
Sistemas Computadorizados de Registros Médicos , Sistemas de Informação em Radiologia , Filme para Raios X
6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-342904

RESUMO

In this paper, by describing and comparing different implementations of electronic film combined with the actual application of the electronic film in the imaging department and the clinical departments. We elaborate electronic film for optimizing the imaging department workflow to improve service quality and patient satisfaction and other aspects of value.


Assuntos
Diagnóstico por Imagem , Sistemas de Informação Hospitalar , Garantia da Qualidade dos Cuidados de Saúde , Inquéritos e Questionários , Filme para Raios X
7.
Chinese Journal of Digestion ; (12): 532-538, 2012.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-429211

RESUMO

Objective To explore the alteration of brain pain functional areas in patients with functional dyspepsia (FD) irritable bowel syndrome (IBS) overlap by rectal balloon volume stimulation and magnetic resonance imaging (MRI) and the differences with IBS alone patients and healthy individuals were compared.Methods A total of 11 IBS alone patients,16 IBS overlapped with FD patients (IBS-FD) and 10 healthy controls were recruited.Sensory thresholds and visual analogue scale (VAS) were recorded during the rectal balloon air injection process. The changes of brain activated areas were analyzed by functional MRI (fMRI) when the rectum was stimulated at the volume of 50,100 and 150 ml.The data were analyzed by least significant difference (LSD) test.Results Under rectal volumetric stimulation,the sensory thresholds of IBS-FD group and IBS alone group were (53.14 ± 16.05) ml and (59.20 ± 20.55) ml and the difference was not statistically significant (LSD test,P>0.05).There was no significant difference in VAS score between IBS alone group and IBS-FD group (LSD test,P>0.05).Rectal stimulated under different volume,the results of fMRI indicated the activation of anterior cingulated cortex, dorsolateral prefrontal cortex,postporietal cortex,thalamus and insular cortex in both IBS alone group and IBS-FD group.And there was no significant difference in activated areas and intensity between IBS alone group and IBS-FD group (LSD test,P>0.05).Conclusions There was no significant difference in activations of brain areas between IBS alone and IBS-FD patients under rectal volumetric stimulation. Under rectal volumetric stimulation,although symptoms overlapped,there was no evidence of the overlap of braingut axis and visceral hypersensitivity between IBS alone and IBS-FD.

8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-418570

RESUMO

ObjectiveTo explore the characteristics multi-detector-row computed tomography (MDCT)findings of ACTH-independent macronodular adrenal hyperplasia ( AIMAH ).Methods The un-enhanced and contrast-enhanced MDCT features in 24 patients ( 14 males and 10 females) with clinically confirmed AIMAH were retrospectively assessed for the morphology and enhancement patterns.ResultsThe adrenal glands were involved bilaterally in all of the 24 cases( 100% ).24 patients had massively enlarged multinodular adrenal glands.Nodules were( 1.79 ± 1.02) cm (0.50 ~ 3.85 cm),which usually distorted and completely obscured the normal adrenal glands.The enlarged adrenal glands were still retained the adreniform contour,showed characteristic ginger-like.22 of the 24 ( 91.7 % ) hyperplastic nodular glands demonstrated mild homogeneous enhancement.Calcification was revealed in 1 adrenals ( 1/24,4.2% ).Conclusion MDCT reveals the characteristic morphology and CT attenuation in AIMAH.Combined with its clinical presentation and biochemical findings,AIMAH is able to be diagnosed with high specificity and accuracy on MDCT.

9.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-82041

RESUMO

OBJECTIVE: To investigate the relationship between the perfusion CT features and the clinicopathologically determined prognostic factors in advanced gastric cancer cases. MATERIALS AND METHODS: A perfusion CT was performed on 31 patients with gastric cancer one week before surgery using a 16-channel multi-detector CT (MDCT) instrument. The data were analyzed with commercially available software to calculate tumor blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS). The microvessel density (MVD), was evaluated by immunohistochemical staining of the surgical specimens with anti-CD34. All of the findings were analyzed prospectively and correlated with the clinicopathological findings, which included histological grading, presence of lymph node metastasis, serosal involvement, distant metastasis, tumor, node, metastasis (TNM) staging, and MVD. The statistical analyses used included the Student's t-test and the Spearman rank correlation were performed in SPSS 11.5. RESULTS: The mean perfusion values and MVD for tumors were as follows: BF (48.14+/-16.46 ml/100 g/min), BV (6.70+/-2.95 ml/100 g), MTT (11.75+/-4.02 s), PS (14.17+/-5.23 ml/100 g/min) and MVD (41.7+/-11.53). Moreover, a significant difference in the PS values was found between patients with or without lymphatic involvement (p = 0.038), as well as with different histological grades (p = 0.04) and TNM stagings (p = 0.026). However, BF, BV, MTT, and MVD of gastric cancer revealed no significant relationship with the clinicopathological findings described above (p > 0.05). CONCLUSION: The perfusion CT values of the permeable surface could serve as a useful prognostic indicator in patients with advanced gastric cancer.


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Linfática , Microcirculação , Prognóstico , Estudos Prospectivos , Fluxo Sanguíneo Regional , Neoplasias Gástricas/irrigação sanguínea , Tomografia Computadorizada por Raios X
10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-572547

RESUMO

Objective To compare the diagnostic accuracy of magnetic resonance (MR) images with multislice computer tomography (MSCT) for preoperative T-staging of patients with cardiac cancer. Methods MR and MSCT were performed in 28 cases of cardiac cancer diagnosed by biopsy prior to operation within one week. After an oral intake of 1000 ml water and an injection of hypotonic agent, MR and MSCT scan were carried out. MR sequences included FSE T1W, FSE T2W, FSE T1W with fat suppression and dynamic enhanced FSPGR with fat suppression. MSCT was applied with dynamic triphasic contrast enhancement. All of the findings were prospectively analyzed by two doctors separately and compared with the surgical and pathological findings. Results According to histopathologic staging, the accuracy of MR and MSCT in T1-staging were 88.8% and 11.1%, in T2-staging were 77.8% and 22.2%, in T3-staging were 83.3% and 32.7%, in T4-staging were 100.0% and 50.0%, respectively. Dynamic enhanced and delayed MR with fat suppression was superior to MSCT for revealing the involvement of esophagus and aorta, early stage of invasiveness and providing more evidences in T2 to T3 or T3 to T4 staging (P

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