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Objective:To explore the influence of different mental status (evaluated by Likert scale) on the first success rate, image artifacts and examination time of cone beam CT (CBCT) in infants and young children.Methods:Prospective analysis of children aged 1-6 years (98 cases) who underwent CBCT examination, before the examination, the children were scored in seven aspects: activity, adaptability, attention, mood, gender, age and parents′ attitude, and the total score was calculated, The total score was used as the test variable, and the success rate of the first examination, the artifact of the image and whether the examination time was longer than 2 minutes were used as the state variable. Using SPSS 16.0 to draw the ROC curve, the area under curve (AUC), significance, maximum Yoden′s index and their corresponding diagnostic (evaluation) critical values were obtained.Results:The success rate of the first examination was 78.6%(77/98), the AUC was 0.949 ± 0.025, the significance P < 0.05, the maximum Yoden′s index was 0.766, the corresponding critical value of diagnosis (evaluation) was 15; the artifact-free rate was 67.3%(66/98), the AUC was 0.873±0.038, the significance P < 0.05, the maximum Yoden′s index was 0.549, and the corresponding critical value of diagnosis (evaluation) was 15; the proportion of examination time in 2 minutes was 80.6%(79/98), the AUC was 0.854 ± 0.039, the significant P < 0.05, the maximum Yoden′s index was 0.614, and the corresponding critical value of diagnosis (evaluation) was 14. Conclusions:The Likert scale scoring method based on Thomas′s temperament analysis theory has certain application value in the psychological evaluation of children before cone-beam CT examination. For children whose total score is greater than or equal to 14, sedation or psychological counseling should be carried out before examination in order to effectively improve the success rate of examination and reduce the occurrence rate of artifacts in images, further more to reduce radiation dosage and increase the examination circulation of CBCT in children.
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Objective:To assess the diagnostic efficient of mean counting ratio method, and to simplify and improve the semi-quantitative method of defining excessive uptake of thyroid nuclides.Methods:One hundred and nine imaging results of thyroid scan in Dalian Municipal Central Hospital from April 2017 to January 2018 were delineated the FOI by two experienced deputy chief physicians and the ratio of average counts per unit area was determined. Clinical diagnosis of hyperthyroidism was used as gold standard, and receptor operation characteristic (ROC) curve was drawn and the optimal diagnostic threshold was calculated. The sensitivity, specificity, accuracy, positive and negative predictive values were calculated and the consistency of the two physicians′ diagnosis was analyzed.Results:The best diagnostic threshold was 6.94 by drawing ROC curve from the measurements of two physicians. The value greater than this was used as a criterion to define the excessive uptake of technetium in thyroid gland. For doctor 1, the sensitivity, specificity and accuracy of differential diagnosis of hyperthyroidism based on diagnostic threshold were 86.0%(37/43), 100.0%(66/66) and 95.5%(103/109), respectively. For doctors 2, they were 88.4%(38/43), 100.0%(66/66) and 95.4%(104/109), respectively. The concordance rate was 96.6%(86/89), interclass correlation coefficient (ICC) was 0.98.Conclusions:Average counting ratio method provides reliable semi-quantitative cut off value for differential diagnosis of high Tc uptake. It has good application value. Different physicians independently complete the semi-quantitative analysis of Tc uptake by average counting ratio method, which has good consistency. In practice, it is simpler and easier than the thyroid/background ratio method.
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Objective@#To discuss the success rate and image quality in pediatric patients who used chloral hydrate before their cone beam computed tomography exam.@*Methods@#1752 patients aged 1 to 6 were selected for this retrospective study. They were divided into sedated group (219 cases) and non-sedated group (1 533 cases). The success rate and image quality were compared between two groups.@*Results@#The sedated group had a higher success rate to non-sedated group: 99.5%(218/219) vs. 90.4% (1 386/1 533). The motion artifact in sedated group was lower than non- sedated group with I degree: 4.8% (15/314) vs. 20.1%(327/1 630) and II degree: 0.3%(1/314) vs. 12.2%(199/1 630).@*Conclusion@#Giving chloral hydrate to pediatric patients before their CBCT exam would improve both success rate and image quality, and reduce unnecessary radiation expose.
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Objective To discuss the success rate and image quality in pediatric patients who used chloral hydrate before their cone beam computed tomography exam. Methods 1752 patients aged 1 to 6 were selected for this retrospective study. They were divided into sedated group (219 cases) and non-sedated group (1 533 cases). The success rate and image quality were compared between two groups. Results The sedated group had a higher success rate to non-sedated group: 99.5%(218/219) vs. 90.4% (1 386/1 533). The motion artifact in sedated group was lower than non-sedated group with I degree: 4.8% (15/314) vs. 20.1%(327/1 630) and II degree: 0.3%(1/314) vs. 12.2%(199/1 630). Conclusion Giving chloral hydrate to pediatric patients before their CBCT exam would improve both success rate and image quality, and reduce unnecessary radiation expose.
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Objective To evaluate the multi-spiral CT(MSCT)imaging features and classification of renal pelvis carcinoma.Meth-ods 76 patients of renal pelvis carcinoma proved pathologically were analyzed retrospectively,and divided into different types ac-cording to the MSCT features.The MSCT differences for different types were analyzed.Results Most of the tumors showed iso-density or slight hyperdensity (95%)on un-enhanced images,and persistent mild-to-moderate enhancement (91%)in enhanced im-ages.All cases were divided into three types:pelvic mass type in 30 cases (39%),substance invasion type in 25 cases (33%),wall thickening type in 21 cases (28%).All cases were also divided into two types:substance invasion type(25 cases,33%)and renal pelvis type(5 1 cases,67%).The occurrence rate of local low enhancement,whole kidney low enhancement,hydronephrosis,lymph node metastasis and vein tumor thrombus were 80%,20%,48%,52%,1 6% in substance invasion type cases,and 4%,42%, 75%,4%,6% in the renal pelvis type cases,respectivily.Conclusion MSCT multiphase enhancement scanning shows important valuation in the diagnosis and classification of renal pelvis carcinoma.Obvious differences of CT features are showed for different types.The diagnosis accuracy may be improved by the knowledge of substance invasion type.
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Objective To investigate the effects of chin lift on the patency of upper airway in normal conscious adults using magnetic resonance imaging (MRI).Methods Sixteen healthy volunteers aged 21-35 yr with a body mass index of 17-26 kg/m2 were enrolled in this study.The subjects lay on their back with their heads slightly extended.The lower jaw was first left in standard position.The mouth was slightly open (the distance between the upper and lower incisors was 0.5 cm).The chin was then lifted upward.The upper airway (from the base of slull to the level of vocal cord) was scaned by MRI along the median sagital plane.The length of soft palate,root of tongue and epiglottis and the area of pharyngeal cavity were measured.The position of the rim of epiglottis was examined.The mean percentage changes induced by chin lift were calculated.Results Compared with standard position,chin lift significantly prolonged the length of soft palate,root of tongue and epiglottis and increased the area of pharyngeal cavity.The percentage change in the position of the rim of epiglottis was largest after chin lift.Conclusion Chin lift significantly improve the patency of the upper airway in conscious adult by changing the position of the rim of epiglottis and increasing the area of pharyngeal cavity.