Objective:To explore age-related variations in the angle of the cochlear basal turn using temporal bone CT, providing a reference for selecting the optimal Stenvers position radiographic projection angle in children and adults.Methods:The retrospective study included children and adults who underwent temporal bone CT scans at Beijing Tongren Hospital from November 2014 to April 2023. A total of 620 participants were included, including 368 males and 252 females. Patients were divided into 20 age-ralated groups: infants under one year old (3 to 11 months) were divided into monthly subgroups (9 groups); children and adolescents aged 1 to 18 years were grouped biennially (9 groups); adults were divided into two groups: 19 to 29 years and 30 to 40 years. Using multiplanar reconstruction (MPR) techniques, the CT images of the temporal bone were reformatted into oblique transverse sections to maximize the visibility of the cochlear basal turn.The cochlear basal turn angle was defined as the angle between the vertical axis of the cochlear basal turn and the mid-sagittal plane of the skull. Statistical analysis was performed to compare age-related differences in cochlear basal turn angles. Two additional patients were included to compare Stenvers position X-ray images with corresponding temporal bone CT scans, assessing the visibility of cochlear implant electrodes post-implantation.Results:Among infants aged 3 to 11 months, the cochlear basal turn angle was 29.4°±4.5°, with no significant differences observed between subgroups ( P>0.05). However, significant differences were found between infants (<1 year old) and the 1-2-year-old group compared to each age group from 3 to 40 years ( P<0.05). Additionally, the angles differed significantly between the 3-14-year-old groups and the 19-40-year-old groups ( P<0.05), whereas no significant differences were found among the remaining groups ( P>0.05). The visibility of the cochlear implant electrodes, appearing round in shape on standard Stenvers position X-ray images, closely resembled that observed in temporal bone CT scans. Conclusion:Age-related variations in the cochlear basal turn angle provide a valuable reference for optimizing Stenvers position radiography angles after cochlear implantation, improving the accuracy and quality of post-implantation imaging.

OBJECTIVE: To observe the effects of Xingnao Kaiqiao acupuncture technique (for regaining consciousness and opening orifice) on methylation of N6-methyladenosine (m6A), and key methyltransferases and demethylases, so as to clarify the mechanism of acupuncture on cerebral ischemia-reperfusion injury (CIRI). METHODS: Of 68 male Sprague-Dawley rats of SPF grade, 15 rats were randomly selected as a sham-operation group, and the remaining rats were subjected to the model of middle cerebral artery occlusion using the suture ligation. CIRI was induced by ischemia for 2 h followed by reperfusion. Rats that failed to modeling or died were excluded. The rest 45 rats were randomly divided into three groups, i.e. model group, acupuncture group, and non-point acupuncture group, with 15 rats in each group. The rats in the acupuncture group were treated with acupuncture at bilateral "Neiguan" (PC6) and "Shuigou" (GV26). In the non-point acupuncture group, acupuncture was delivered at three non-points, located 3 mm below the bilateral midaxillary line and 3 mm lateral to the tip of the coccyx. One intervention was operated in these two acupuncture groups and the needles were retained for 30 min. Before modeling start and 2 h after ischemia, a laser speckle flowmeter was used to monitor the cerebral blood perfusion. In 2 h of ischemia and 24 h of reperfusion, the neurological behavioral score was evaluated. The volume of rat cerebral infarction was determined by triphenyltetrazolium chloride (TTC) staining, and the level of m6A methylation in ischemic cortical area was detected by Dot blot, and the protein and mRNA expression of the demethylase i.e. fat mass and obesity-associated protein (FTO), AlkB homolog 5 (ALKBH5) and key methyltransferases, i.e. methyltransferase-like 3 (METTL3), methyltransferase-like 14 (METTL14), and Wilms' tumor 1-associated protein (WTAP) in ischemic cortical area were detected by Western blot and real-time PCR. RESULTS: Cerebral blood perfusion decreased by>70% after 2 h ischemia. Compared with the sham-operation group, the neurobehavioral score and the percentage of cerebral infarction volume increased in the model group (P<0.01); the level of m6A methylation in the ischemic cortical area increased (P<0.01), the protein and mRNA expression of FTO decreased (P<0.01), and that of ALKBH5, METTL3, and METTL14 increased (P<0.01, P<0.05) in the model group. When compared with the model group and the non-point acupuncture group, the acupuncture group showed a decrease in the neurobehavioral score and the percentage of cerebral infarction volume (P<0.01), the level of m6A methylation in the ischemic cortical area was reduced (P<0.01, P<0.05), and the protein and mRNA expression of FTO was elevated (P<0.01). CONCLUSION Xingnao Kaiqiao acupuncture technique presents its protective effect on the brain in the rats with CIRI, which is related to up-regulating the expression of FTO and modulating m6A methylation.
Animals ; Rats, Sprague-Dawley ; Male ; Acupuncture Therapy ; Reperfusion Injury/genetics* ; Rats ; Brain Ischemia/genetics* ; Humans ; Adenosine/metabolism* ; Methylation ; Acupuncture Points ; Cerebral Cortex/metabolism*

Objective:To investigate the status and diagnostic reference levels (DRLs) of adult CT radiation dose based on survey result from some hospitals in Beijing.Methods:From September to December 2023, the survey results for 50 hospitals were collected in Beijing, including 47 tertiary hospitals and 3 second grade general hospitals. The CT data sets in total of 20 items including head (sequential scanning), head (spiral scanning), head perfusion, sinus, neck, chest, chest (low dose scanning), abdomen, pelvis, abdomen-pelvis, chest-abdomen-pelvis, lumbar spine, CT urography, coronary CTA (retrospective), coronary CTA (prospective), head CTA, neck CTA, aorta CTA, leg CTA and knee were collected on clinical commonly used CT scanners with annual qualified state inspection. For each item, radiation dose data was collected continuously and randomly for up to 50 cases for every CT scanner. Using the volume CT dose index (CTDI vol) and dose length product (DLP) as dose parameters, the median value of each item in each hospital was obtained. The median CTDI vol and DLP values of all hospitals were arranged, and the local DRL of each item was set as the 75th percentile of the median values. The obtained DRLs were compared with the DRLs issued by domestic and international radiological protection organizations. Results:A total of 26 031 dose values of adult patients were collected and 25 996 dose values were left while 35 invalid values removed.For different CT users, CTDl vol, DLP and scanning phases were different for the same item. The five items with the highest CTDI were head perfusion, head sequential scanning, head spiral scanning, coronary CTA (retrospective mode), and sinus. The five items with the highest DLP were CTU, head perfusion, leg CTA, chest-abdomen-pelvis and aortic CTA. The CTDI vol of CTU was only 16.9 mGy (75th percentile), while the DLP was as high as 2 394.9 mGy·cm (75th percentile). The survey showed that the DRLs of most items in Beijing was lower than the national DRLs of domestic and foreign standards, and the DRLs of a small number of items were slightly higher. Conclusion:The current CT dose level in Beijing is not consistent with national DRLs released at home and abroad, so it is necessary to establish local DRLs according to the clinical status in Beijing.

Objective:To investigate the radiation dose levels of digital radiography (DR) in adult patients and explore the diagnostic reference level (DRL) of radiation dose in Beijing.Methods:Radiation dose data were collected from 39 medical institutions in Beijing on 18 930 DR examinations of chest anterior and lateral view, abdomen anterior and posterior view, abdomen standing view, cervical spine anterior and lateral view, lumbar spine anterior and lateral view, knee joint anterior and lateral view as well as 5 266 digital mammography (CC view and MLO view). For ordinary DR examinations, the incident air kinetic energy ( Ka, i), incident air specific kinetic energy area product ( PKA) and effective dose ( E) to the examined individuals were used for the investigation and estimation of radiation dose. For digital mammography, the average glandular dose (AGD) was calculated. DRLs should be set at the 75 th percentile of median values obtained in each medical institution. Results:The Ka, i, PKA and E of DRL for Chest (PA), Chest (lateral), abdominal(PA), abdominal (AP), Pelvic(AP), Cervical (AP), Cervical (lateral), Lumbar (AP), Lumbar (lateral), Knee joint (AP) and Knee joint (lateral) of conventional DR were 0.14, 0.31, 1.25, 2.18, 1.86, 0.51, 0.14, 2.97, 8.39, 0.37, 0.37 mGy, 159, 259, 1 917, 2 336, 2 867, 312, 301, 3 500, 3 359, 269, 255 mGy·cm 2, 0.03, 0.05, 0.20, 0.43, 0.23, 0.03, 0.02, 0.47, 0.35, <0.001, <0.001 mSv. The DRLs for digital mammography were calculated to be 1.87 mGy (CC view), 1.94 mGy (MLO view) and 3.99 mGy (accumulated for one examination). Conclusions:The radiation dose from DR examinations is relatively low. In clinical practice, the selection of imaging parameters should be further standardized on the basis of the local DRL.

Objective:To investigate the status and diagnostic reference levels (DRLs) of adult CT radiation dose based on survey result from some hospitals in Beijing.Methods:From September to December 2023, the survey results for 50 hospitals were collected in Beijing, including 47 tertiary hospitals and 3 second grade general hospitals. The CT data sets in total of 20 items including head (sequential scanning), head (spiral scanning), head perfusion, sinus, neck, chest, chest (low dose scanning), abdomen, pelvis, abdomen-pelvis, chest-abdomen-pelvis, lumbar spine, CT urography, coronary CTA (retrospective), coronary CTA (prospective), head CTA, neck CTA, aorta CTA, leg CTA and knee were collected on clinical commonly used CT scanners with annual qualified state inspection. For each item, radiation dose data was collected continuously and randomly for up to 50 cases for every CT scanner. Using the volume CT dose index (CTDI vol) and dose length product (DLP) as dose parameters, the median value of each item in each hospital was obtained. The median CTDI vol and DLP values of all hospitals were arranged, and the local DRL of each item was set as the 75th percentile of the median values. The obtained DRLs were compared with the DRLs issued by domestic and international radiological protection organizations. Results:A total of 26 031 dose values of adult patients were collected and 25 996 dose values were left while 35 invalid values removed.For different CT users, CTDl vol, DLP and scanning phases were different for the same item. The five items with the highest CTDI were head perfusion, head sequential scanning, head spiral scanning, coronary CTA (retrospective mode), and sinus. The five items with the highest DLP were CTU, head perfusion, leg CTA, chest-abdomen-pelvis and aortic CTA. The CTDI vol of CTU was only 16.9 mGy (75th percentile), while the DLP was as high as 2 394.9 mGy·cm (75th percentile). The survey showed that the DRLs of most items in Beijing was lower than the national DRLs of domestic and foreign standards, and the DRLs of a small number of items were slightly higher. Conclusion:The current CT dose level in Beijing is not consistent with national DRLs released at home and abroad, so it is necessary to establish local DRLs according to the clinical status in Beijing.

Objective:To investigate the radiation dose levels of digital radiography (DR) in adult patients and explore the diagnostic reference level (DRL) of radiation dose in Beijing.Methods:Radiation dose data were collected from 39 medical institutions in Beijing on 18 930 DR examinations of chest anterior and lateral view, abdomen anterior and posterior view, abdomen standing view, cervical spine anterior and lateral view, lumbar spine anterior and lateral view, knee joint anterior and lateral view as well as 5 266 digital mammography (CC view and MLO view). For ordinary DR examinations, the incident air kinetic energy ( Ka, i), incident air specific kinetic energy area product ( PKA) and effective dose ( E) to the examined individuals were used for the investigation and estimation of radiation dose. For digital mammography, the average glandular dose (AGD) was calculated. DRLs should be set at the 75 th percentile of median values obtained in each medical institution. Results:The Ka, i, PKA and E of DRL for Chest (PA), Chest (lateral), abdominal(PA), abdominal (AP), Pelvic(AP), Cervical (AP), Cervical (lateral), Lumbar (AP), Lumbar (lateral), Knee joint (AP) and Knee joint (lateral) of conventional DR were 0.14, 0.31, 1.25, 2.18, 1.86, 0.51, 0.14, 2.97, 8.39, 0.37, 0.37 mGy, 159, 259, 1 917, 2 336, 2 867, 312, 301, 3 500, 3 359, 269, 255 mGy·cm 2, 0.03, 0.05, 0.20, 0.43, 0.23, 0.03, 0.02, 0.47, 0.35, <0.001, <0.001 mSv. The DRLs for digital mammography were calculated to be 1.87 mGy (CC view), 1.94 mGy (MLO view) and 3.99 mGy (accumulated for one examination). Conclusions:The radiation dose from DR examinations is relatively low. In clinical practice, the selection of imaging parameters should be further standardized on the basis of the local DRL.

Objective:To explore age-related variations in the angle of the cochlear basal turn using temporal bone CT, providing a reference for selecting the optimal Stenvers position radiographic projection angle in children and adults.Methods:The retrospective study included children and adults who underwent temporal bone CT scans at Beijing Tongren Hospital from November 2014 to April 2023. A total of 620 participants were included, including 368 males and 252 females. Patients were divided into 20 age-ralated groups: infants under one year old (3 to 11 months) were divided into monthly subgroups (9 groups); children and adolescents aged 1 to 18 years were grouped biennially (9 groups); adults were divided into two groups: 19 to 29 years and 30 to 40 years. Using multiplanar reconstruction (MPR) techniques, the CT images of the temporal bone were reformatted into oblique transverse sections to maximize the visibility of the cochlear basal turn.The cochlear basal turn angle was defined as the angle between the vertical axis of the cochlear basal turn and the mid-sagittal plane of the skull. Statistical analysis was performed to compare age-related differences in cochlear basal turn angles. Two additional patients were included to compare Stenvers position X-ray images with corresponding temporal bone CT scans, assessing the visibility of cochlear implant electrodes post-implantation.Results:Among infants aged 3 to 11 months, the cochlear basal turn angle was 29.4°±4.5°, with no significant differences observed between subgroups ( P>0.05). However, significant differences were found between infants (<1 year old) and the 1-2-year-old group compared to each age group from 3 to 40 years ( P<0.05). Additionally, the angles differed significantly between the 3-14-year-old groups and the 19-40-year-old groups ( P<0.05), whereas no significant differences were found among the remaining groups ( P>0.05). The visibility of the cochlear implant electrodes, appearing round in shape on standard Stenvers position X-ray images, closely resembled that observed in temporal bone CT scans. Conclusion:Age-related variations in the cochlear basal turn angle provide a valuable reference for optimizing Stenvers position radiography angles after cochlear implantation, improving the accuracy and quality of post-implantation imaging.

Objective:To construct a spatial radiomics model based on the spatial distribution characteristics of supratentorial pilocytic astrocytoma (PA) and ganglioglioma (GG) and to evaluate its differential diagnosis efficiency.Methods:The study was a cross-sectional study. A retrospective collection of 244 patients with episodic PA and GG who attended Beijing Tiantan Hospital of Capital Medical University (Center 1) from June 2016 to June 2022 and 116 patients with episodic PA and GG who attended General Hospital of Eastern Theater Command (Center 2) from March 2019 to October 2022 was performed. The patients in Center 1 were divided into a training set (171 patients) and a validation set (73 patients) in a 7∶3 ratio according to the random number table method, and the patients in Center 2 as a whole were regarded as test sets. All patients underwent MRI. Segmentation of tumor based on enhanced T 1WI and T 2WI images, alignment to standard space to generate a statistical parametric mapping of tumor locations and intergroup comparison was conducted. The Johns Hopkins University template was used to extract 189 tumor location features to construct a spatial model of tumor location; PyRadiomic 3.0.1 software was used to extract tumor radiomics features to construct a radiomics model; and the two models were fused to construct a spatial radiomics model. The efficacy of spatial radiomics model, spatial model, and radiomics model to discriminate PA from GG was analyzed using receiver operating characteristic curves and area under the curve (AUC). The generalization ability of the model was assessed by the difference in accuracy between the test sets and the validation sets (ΔACC). The clinical utility of the model was compared using clinical decision curves and calibration curves. Results:The statistical parametric mapping of lesions showed that supratentorial PA was vulnerable to medial structure areas such as suprasellar region, thalamus, basal ganglia and frontal lobe, temporal lobe, parietal lobe. GG was mainly distributed in bilateral temporal lobes, as well as frontal lobe, occipital lobe and parietal lobe. The AUCs of spatial radiomics model, radiomics model and spatial model to identify PA and GG in the test set were 0.876, 0.785, and 0.819, with accuracies of 77.59%, 72.41%, and 77.14%, respectively, and ΔACCs in the test set and validation set were 11.6%, 15.43%, and 6.94%, respectively. The clinical decision curves showed an overall greater clinical benefit of the spatial radiomics model compared with the conventional radiomics model and spatial model.Conclusion:Spatial radiomics model containing spatial information on lesion location can improve the diagnostic efficacy of supratentorial PA and GG, and enhance the generalization of the prediction model.

Objective:To explore and compare the impacts of different scanning protocols on image quality and radiation dose in chest computed tomography (CT) scans.Methods:A retrospective analysis was conducted for the data of 65 randomly selected patients who underwent chest CT scans using a tube voltage of 120 kV, the automatic modulation technique for tube current, and z-axis radiation dose modulation at the Emergency Department of our hospital from June to July 2023. The enrolled cases were divided into two groups: the high-resolution group ( n = 34) and the conventional group ( n = 31), with the settings for scanning protocols identical to those for phantom scans. For patients in both groups, thin-layer images of the cross-sections in the lung and mediastinal windows were reconstructed using thickness/intervals of 1 mm/1 mm and 2 mm/1 mm, respectively. Meanwhile, high-resolution and conventional CT scans were conducted using a Catphan500 phantom under a tube voltage of 120 kV and a tube current of 150 mAs. Of both scanning protocols, the high-resolution CT scan utilized the lung nodule-orientated scanning mode, pitch of 1.5, and a detector combination providing a collimation of 16 × 0.75 mm. In contrast, the conventional CT scan was performed using the body-orientated scanning mode, pitch of 0.813, and a detector combination providing a collimation of 16 × 1.5 mm. Then, the high-contrast resolutions of the phantom images obtained using the two scanning protocols were objectively evaluated. Both coronal chest images in the lung window and cross-sectional images in the mediastinal window were reconstructed with a thickness/interval of 5 mm/5 mm for both groups. Then, the obtained images were imported into the Radimetrics system to compare the body size-specific dose estimation (SSDE), doses to sensitive organs on the body surface, and scanning time of both groups. For the cross-sectional images in the mediastinal window, the contrast-noise-ratio (CNR), signal-to-noise ratio (SNR), and figure-of-merit (FOM) were measured and calculated at the fixed anatomical parts. For the cross-sectional images in the lung window, their quality was subjectively evaluated by two senior diagnostic radiologists. Results:The result of phantom scans indicated that high-resolution CT scans yielded images with an approximately 5% increase in the spatial resolution in the xy-plane and a nearly 20% increase in the spatial resolution along the z-axis compared to conventional CT scans. The result of clinical data demonstrated that the conventional group exhibited significantly higher doses to the thyroid and the female breast ( t = 2.8, 2.3, P < 0.05), along with notably elevated SNR, CNR, and FOM values of the right trapezius, compared to the high-resolution group ( t = 4.1, 5.8, z=4.4, P < 0.001). However, the high-resolution group manifested significantly higher SNR, CNR, and FOM values of the thoracic aorta compared to the conventional group ( t = 3.4, 4.4, z=3.4, P < 0.001). In addition, the cross-sectional and coronal images in the lung window of the clinical cases in the high-resolution group exhibited more stable quality, with subjective scores exceeding 4 and the average scores of both groups not statistically significantly different. Conclusions:For chest CT examination, high-resolution CT scans are more suitable for observations focusing on the details of the lungs and mediastinum, while conventional CT is more suitable for those centering on soft tissues on the body surface.

Objective:To investigate the trend of radiological diagnostic examination frequency and the related influencing factors in a general hospital in recent four years.Methods:The hospital information system and the radiology information system were used to collect the information on the numbers of the outpatients, the emergency patients, and the inpatients and the radiology examination information from 2019 to 2022. The examination frequency and proportion of various imaging equipment were counted by using the perspective table of data, and the examination items and the proportion of the radiological diagnostic examinations were calculated. The positive rates of the radiological examinations were measured from 2019 to 2022. The gender and age distribution of the patients were analyzed. Spearman correlation analysis was used to analyze the relationships between the numbers of the patients undergoing radiological examinations and the numbers of the outpatients, emergency patients and the inpatients.Results:The annual frequency of radiological diagnostic examinations from 2019 to 2022 were 307 306, 245 418, 317 250 and 325 625, respectively, with a total of 1 195 599. Among them, the proportions of CT, X-rays, bedside X-rays, bone density, gastrointestinal imaging and mammography were 59.74%, 38.04%, 1.39%, 0.42%, 0.21% and 0.19%, respectively. In each year, the proportion of CT in all radiological diagnostic examinations was 49.58%, 63.40%, 60.40% and 65.20%, respectively. The frequency of emergency CT and emergency chest CT was correlated with the number of emergency patients( r =0.63, 0.61, P<0.05), and the frequency of non-emergency CT was correlated with the number of outpatients and inpatients ( r =0.61, 0.66, P<0.05). The positive rates of the CT examinations were higher than 80% except the lowest of 79.95% in 2021. Conclusions:Radiological examinations especially CT examinations have increased significantly, and played an important role in the diagnosis of diseases. However, attention should be paid to the Justification of the CT examinations. Timely statistical analysis of radiological examination information can provide data supports and references for scientific management of radiological examinations.