Application Value Of Sinus CT Low-Dose Scanning Combined With Adaptive Statistical Iterative Reconstruction For Children

BackgroundSinusitis is one of the most common diseases in childhood,and it has a fairly high incidence in children.With the continuous development of various aspects of society in recent years,the air quality has gradually decreased;and owing to the not well developed respiratory tract and low own immunity,tender and weak the nasal mucosa that rich in lymphatic vessels and blood vessels but easy to congestion and swelling after infection,also,the relatively narrow ostiomeatal complex?OMC?that often accompanied by adenoid hypertrophy,the incidence rate of sinusitis in children is high and has an increasing trend.Sinusitis triggers nasal congestion,headache,purulent nasal discharge,cough,and even asthma in children;outward spread induces otitis media,pharyngitis,tonsillitis,and even orbital infection and intracranial complications.Children often have difficulty concentrating,drowsiness and apathy,and chronic sinusitis can also affect children's facial development,intelligence and memory.Therefore,sinusitis can significantly reduce the quality of life and learning efficiency of children.Computed tomography?CT?plays a pivotal role in sinus imaging.Routine CT examination has a higher X-ray radiation dose.The children in the stage of growth and development are much more sensitive to radiation than adults,and the corresponding radiation carcinogenic risk is also greatly increased,especially the sensitive organs within the scanning range,such as lens and thyroid gland.Adaptive statistical iterative reconstruction?ASIR?algorithm can effectively reduce image noise and improve image quality,so that it can obtain images that meet the needs of clinical diagnosis even under low radiation dose scanning conditions.PurposeThe aim of this study is to investigate the feasibility and application value of low tube voltage and low tube current combined with ASIR algorithm in sinus CT examination in children.Materials and MethodsA total of 150 children with nasal obstruction,headache,purulent nasal discharge,cough and other clinical symptoms who came to our hospital for sinus CT scan from April to December 2018 were recruited with an average age of?8.23±2.48?years.The children were randomly divided into three groups,the regular dose group,the low-dose group A and group B with 50 cases in each.In the regular dose group,120 kV and 90 mA scans were applied to reconstruct images with filtered back projection?FBP?;in the low-dose A and B groups,100 kV and 50 mA scans were used to reconstruct images with FBP and ASIR?50%?,respectively.The subjective score,noise value[with the standard deviation?SD?of CT value as the noise value],contrast to noise ratio?CNR?of each group of images and CT dose index volume(CTDI_vol),dose-length product?DLP?and effective dose?ED?of children were compared and analyzed.Finally,SPSS 20.0 software was used to analyze the data.Results1.The subjective score of low-dose group B?3.52±0.21?was not significantly different from that of regular dose group?3.56±0.17??P>0.05?;the subjective score of low-dose group A?3.11±0.27?was significantly lower than that of regular dose group and low-dose group B,and the difference was statistically significant?P<0.05?.2.The air noise value of inferior turbinate mucosa and nasopharyngeal cavity increased and CNR decreased in the low-dose A and B comparing to regular dose groups,and the difference was statistically significant?P<0.05?;the fat noise value of infratemporal fossa increased,and the difference was statistically significant between the low-dose A and regular dose group?P<0.05?,but there was no significant difference in the fat noise value of infratemporal fossa in the low-dose B and regular dose group?P>0.05?.3.CTDIvol,DLP and ED were significantly lower in low-dose group A and group B than those in regular dose group,and the difference was statistically significant?p<0.05?.Conclusion1.In pediatric sinus CT examination,reducing the tube voltage and tube current can greatly reduce the X-ray radiation dose received by children.2.ASIR can significantly reduce image noise and increase the contrast-to-noise ratio,thereby improving image quality.3.Appropriate reduction of scanning parameters combined with ASIR algorithm can significantly reduce the radiation dose under the premise of obtaining images meeting the needs of clinical diagnosis.