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1.
Journal of Huazhong University of Science and Technology (Medical Sciences) ; (6): 616-20, 2014.
Artigo em Inglês | WPRIM | ID: wpr-636774

RESUMO

The influence of low tube voltage in dual source CT (DSCT) coronary artery imaging on image quality and radiation dose and its application value in clinical practice were investigated. Totally, 300 cases of chest pain with low body mass index (BMI 0.05). The CTDIvol values in groups A, B and C were 51.35±12.21, 21.28±7.13 and 6.34±3.34 mGy, respectively, with the difference being statistically significant (P<0.05). The ED values in groups A, B and C were 9.27±1.63, 4.56±2.29 and 2.29±1.69 mSv, respectively, with the difference being statistically significant (P<0.05). It was suggested that for the patients with low BMI, the application of DSCT coronary artery imaging with low tube voltage can obtain satisfactory image quality, and simultaneously, significantly reduce the radiation dose.

2.
Journal of Huazhong University of Science and Technology (Medical Sciences) ; (6): 616-620, 2014.
Artigo em Inglês | WPRIM | ID: wpr-351029

RESUMO

The influence of low tube voltage in dual source CT (DSCT) coronary artery imaging on image quality and radiation dose and its application value in clinical practice were investigated. Totally, 300 cases of chest pain with low body mass index (BMI <18.5 kg/m(2)) subjected to DSCT coronary artery imaging were prospectively enrolled. The heart rate in all patients were greater than 65/min. The retrospective ECG gated scanning mode and simple random sampling method were used to assign the patients into groups A, B and C (n=100 each). The patients in groups A, B and C experienced 120-, 100-, and 80-kV tube voltage imaging respectively, and the image quality was evaluated. The CT volume dose index (CTDIvol) and dose length product (DLP) were recorded, and the effective dose (ED) was calculated in each group. The image quality scores and radiation doses in groups were compared, and the influence of tube voltage on image quality and radiation dose was analyzed. The results showed that the excellent rate of image quality in groups A, B and C was 95.69%, 94.72% and 96.33% respectively with the difference being not statistically significant among the three groups (P>0.05). The CTDIvol values in groups A, B and C were 51.35±12.21, 21.28±7.13 and 6.34±3.34 mGy, respectively, with the difference being statistically significant (P<0.05). The ED values in groups A, B and C were 9.27±1.63, 4.56±2.29 and 2.29±1.69 mSv, respectively, with the difference being statistically significant (P<0.05). It was suggested that for the patients with low BMI, the application of DSCT coronary artery imaging with low tube voltage can obtain satisfactory image quality, and simultaneously, significantly reduce the radiation dose.


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Massa Corporal , Dor no Peito , Diagnóstico por Imagem , Angiografia Coronária , Métodos , Vasos Coronários , Diagnóstico por Imagem , Tomografia Computadorizada por Raios X , Métodos
3.
Acta Academiae Medicinae Sinicae ; (6): 13-15, 2006.
Artigo em Chinês | WPRIM | ID: wpr-281273

RESUMO

<p><b>OBJECTIVE</b>To evaluate the usefulness of multi-slice spiral CT (MSCT) in the post-operative assessment of cochlear implanted electrode.</p><p><b>METHODS</b>Twenty-three cochlear implant recipients were enrolled in this study. All patients were examined with a SOMATOM Sensation 16-slice CT scanner (Siemens) using the following parameters: 120 kV, 100 mAs, 0. 75 mm collimation, 1 mm reconstruction slice thickness and increment, a pitch factor of 1, and a FOV of 100 mm. The axial images of interested ears were reconstructed with 0.1 mm increment and a FOV of 50 mm, and then volume rendering technique (VRT) reconstruction were done on the work station.</p><p><b>RESULTS</b>The electrode arrays were detected on axial CT images. Both inner ear and electrode array could be displayed on one image simultaneously. VRT provided an intuitionistic view of the relationship between electrode array and cochlea VRT showed the number of the electrode array in 20 patients implanted with Combi 40 + standard electrode array and demonstrated the shape, position, and insertion depth. The electrode array number determined by VRT was in accordance with the surgical findings in 18 patients, and was underestimated in two patients. In 3 patients with Combi 40 + compressed electrode array, only 4 to 5 electrodes arrays were clearly identified and others were not observed.</p><p><b>CONCLUSION</b>MSCT with VRT can provide useful three-dimensional information of the electrode array and indicate the exact relationship between electrode array and cochlea.</p>


Assuntos
Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Implante Coclear , Implantes Cocleares , Orelha Interna , Diagnóstico por Imagem , Imageamento Tridimensional , Período Pós-Operatório , Tomografia Computadorizada Espiral
4.
Acta Academiae Medicinae Sinicae ; (6): 93-95, 2006.
Artigo em Chinês | WPRIM | ID: wpr-281254

RESUMO

<p><b>OBJECTIVE</b>To study the application of multi-slice spiral CT angiography (MSCTA) after endoluminal exclusion of aortic diseases.</p><p><b>METHODS</b>16-slice CT angiography was performed in 15 patients with aortic dissection and 4 patients with aortic aneurysm after endovascular exclusion. Two observers analysed the images and interpreted the outcomes and complications after endovascular exclusions of aortic dissection and aortic aneurysm.</p><p><b>RESULTS</b>In 19 patients, thrombus was found in all the false lumens of aortic dissection and the outer-stent cavity of aortic aneurysm. However, one patient with aortic aneurysm graft thrombosis; 4 patients had endo-leak (3 with type I endo-leak, 1 with type III endo-leak complicating graft deformation); one achieved perfusion recovery, and one experienced thrombolysis of superior mesenteric artery.</p><p><b>CONCLUSION</b>MSCTA can be an objective tool for the post-operative evaluation of endovascular exclusion of aortic diseases.</p>


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dissecção Aórtica , Diagnóstico por Imagem , Cirurgia Geral , Angiografia , Aneurisma da Aorta Abdominal , Diagnóstico por Imagem , Cirurgia Geral , Período Pós-Operatório , Tomografia Computadorizada Espiral , Métodos
5.
Chinese Journal of Otorhinolaryngology Head and Neck Surgery ; (12): 275-278, 2005.
Artigo em Chinês | WPRIM | ID: wpr-288892

RESUMO

<p><b>OBJECTIVE</b>To evaluate the feasibility and usability of multi-slice computed tomography (MSCT) in congenital inner ear malformations.</p><p><b>METHODS</b>Fourty-four patients with sensorineural hearing loss (SNHL) were examined by a Somatom Sensation 16 (siemens, Germany) CT scanner with following parameters: 120 kV, 100 mAs, 0.75 mm collimation, 1 mm reconstruction increment, a pitch factor of 1 and a field of view of 100 mm. The axial images of interested ears were reconstructed with 0.1 mm reconstruction increment, and a field of view of 50 mm. The 3D reconstructions were done with volume rendering technique (VRT) on the workstation (3D Virtuoso and Wizard,siemens).</p><p><b>RESULTS</b>Twenty-five patients were normal and 19 patients (36 ears) were congenital inner ear malformations among 44 patients scanned with MSCT. Of the malformations, all the axial, MPR and VRT images can display the site and degree in 33 ears. VRT images were superior to the axial images in displaying the malformations in 3 ears with the small lateral semicircular canal malformations. The malformations were Michel deformity (1 ear), common cavity deformity (3 ears), incomplete partition I (3 ears), incomplete partition II (Mondini deformity, 5 ears), vestibular and semicircular canal malformations( 14 ears), vestibular aqueduct dilate( 16 ears, of which 6 ears accompanied by other malformations), the internal auditory canal malformation(8 ears, all accompanied by other malformations).</p><p><b>CONCLUSION</b>MSCT allows a comprehensively assessing various congenital ear malformations through high quality MPR and VRT reconstructions. VRT images can display the site and degree of the malformations three-dimensionally and intuitionisticly. It is very useful to the cochlear implantation.</p>


Assuntos
Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Adulto Jovem , Estudos de Casos e Controles , Anormalidades Congênitas , Diagnóstico por Imagem , Orelha Interna , Anormalidades Congênitas , Diagnóstico por Imagem , Tomografia Computadorizada Espiral
6.
Chinese Medical Journal ; (24): 742-746, 2005.
Artigo em Inglês | WPRIM | ID: wpr-288342

RESUMO

<p><b>BACKGROUND</b>At present, the therapy for patients with lung cancer that achieves a high rate of cure is surgical resection at an early stage of the disease. The aim of this study is to evaluate quantitative computed tomography (QCT) for predicting postoperative pulmonary function in patients with lung cancer.</p><p><b>METHODS</b>The data of thirty-one patients with lung cancer who underwent both pulmonary functional tests and QCT scan before operations were collected. A CT program was used to quantify the volume of whole lung parenchyma with attenuation of -910 HU to -600 HU, which was defined as total functional lung volume (TFLV). Similarly, the volume of lung (lobes or segments) with attenuation of -910 HU to -600 HU was defined as regional functional lung volume (RFLV). Forced vital capacity (FVC), forced expiratory volume in first second (FEV1), FVC% and FEV1% (ratio to reference values of the matched population) were obtained from preoperational pulmonary functional tests. According to the formula: predicted FVC (pre-FVC) = preoperative FVC x [1-(RFLV/TFLV)]; predicted FEV1 (pre-FEV1) = preoperative FEV1 x [1-(RFLV/TFLV)], we obtained values of predicted FVC, predicted FEV1, predicted FVC% (pre-FVC/reference values of the matched population), and predicted FEV1% (pre-FEV1/reference values of the matched population). The paired t test and Pearson correlation test were used to assess significance of differences and correlations between CT predicted values and postoperative measured results of FVC, FEV1, FVC% and FEV1%.</p><p><b>RESULTS</b>QCT predicted values correlated well with postoperative FVC, FEV1, FVC% and FEV1% (r = 0.873, 0.809, 0.849 and 0.801 respectively, all P < 0.01).</p><p><b>CONCLUSIONS</b>QCT is an effective and accurate way to predict postoperative pulmonary function in patients undergoing pulmonary resection, regardless of the patients' preoperative pulmonary functional status.</p>


Assuntos
Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pulmão , Neoplasias Pulmonares , Cirurgia Geral , Período Pós-Operatório , Testes de Função Respiratória , Tomografia Computadorizada por Raios X
7.
Chinese Journal of Radiology ; (12)2001.
Artigo em Chinês | WPRIM | ID: wpr-679935

RESUMO

Objective To evaluate the clinical application of digital radiography(DR)tissue equalization(TE)technique in the femoral neck injury.Methods TE technique and conventional photography were used to examine 50 patients suffering from injury of the femoral neck.The image quality was evaluated by three radiological experts who were blinded to the results.The image quality was divided into five levels.Results When the TE technique was used,38 perfect images were obtained and there was no unacceptable image,while the traditional methods resulted in 12 unacceptable images and no perfect image.The TE technique is superior to the conventional radiography significantly in the lateral photography of the femoral neck(P

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