[Feasibility analysis of the application of programmed process endoscopic lateral neck dissection via chest-breast approach in papillary thyroid carcinoma surgery].

Objective: To explore the feasibility of endoscopic lymph node dissection(LND) with programmed breast approach for the treatment of papillary thyroid cancer. Methods: A case series study. The clinical data of 39 patients with papillary thyroid cancer who underwent endoscopic LND treatment with programmed breast approach in Shenzhen People's Hospital from January to November 2022 were retrospectively analyzed. There were 10 males and 29 females, aged (35.95±10.17) years. LND time, total surgical time, intraoperative bleeding volume, postoperative drainage volume, postoperative hospital stay and postoperative complications were analyzed. Results: Among 39 patients, there were 18 cases of unilateral thyroid cancer, 21 cases of bilateral thyroid cancer, 35 cases of unilateral LND, and 4 cases of bilateral LND. The maximum diameter of thyroid cancer lesions was (1.48±0.69) cm, and the maximum diameter of lymph node metastases was (1.63±0.58)cm. The operative time of unilateral neck dissection was (124.11±19.92) min (102-170 min), and the total operative time was (226.42±55.68) min (110-390 min). The number of lymph nodes cleaned was (32.40±10.44)(12-54), the number of metastasis and detection was 207/1 393. The postoperative drainage volume was (174.64±82.33) ml(41-350 ml). There were no neck hematomas, no skin burns or no shrugging disorders in the postoperative period. There were 7 cases of numbness and discomfort in neck skin sensation, which gradually relieved after half a year. Postoperative discharge time (4.77±1.94) d(3-15 d). Conclusion: It is safe and feasible to treat papillary thyroid cancer with endoscopic LND with programmed breast approach, which can improve surgical efficiency and clinical application value.

[Characteristics and clinical analysis of MLH1 c.463dupC gene mutation in a Lynch syndrome family].

In this study, a case of Lynch syndrome (LS) family line with a novel mutation site in the MLH1 c.463dupC gene was reported and the clinical and pathogenic genetic features of this family were analyzed. A 40-year-old female patient with colon cancer diagnosed at the First Affiliated Hospital of Kunming Medical University on October 2, 2020 was retrospectively included. The clinical data of the family were collected and the family lineage was drawn. The family tumor history met the Amsterdam Criteria Ⅱ and the diagnostic criteria of LS in Chinese, which was a typical LS family lineage. A germline code-shift missense mutation c.463dupC in the MLH1 gene located in exon 6, a possible pathogenic variant, was detected by second-generation sequencing (NGS) in the patient. Subsequently, Sanger sequencing was performed on a total of 20 direct lineage members of the family of the MLH1 gene, 7 cases were found to harbor the mutation and included in the LS high-risk control. Follow-up to October 2023 showed that the patient had endometrial and cervical polyps, one case had colorectal cancer, and two cases had intestinal polyps, all were treated with early intervention and therapy; two cases did not show any clinical symptoms. This study is the first to report a new mutation site for the potentially pathogenic MLH1 c.463dupC, providing a rationale for the pathogenicity of the mutation and standardized health management for familial carriers.

[Allergic bronchopulmonary aspergillosis with low serum IgE: a case report].

Here, we reported a case of delayed diagnosis of allergic bronchopulmonary aspergillosis (ABPA) with low serum IgE and normal Aspergillus fumigatus-specific IgE levels. During the course of the disease, the patient (female, 55 years old) had imaging manifestation of mass shadow and significant elevation of carcinoembryonic antigen, leading to suspicion of a lung tumor. Later, transbronchial lung biopsy tissue culture showed Aspergillus fumigatus. Combined with the history, clinical characteristics and imaging, she was diagnosed with allergic bronchopulmonary aspergillosis combined with invasive pulmonary aspergillosis. As the diagnostic criteria for ABPA do not cover all patients with ABPA, in rare cases where immunological evidence is insufficient, a combination of clinical and imaging features is required for early diagnosis and treatment.

Prediction of high-grade soft-tissue sarcoma using a combined intratumoural and peritumoural MRI-based radiomics nomogram.

AIM: To develop an intratumoural and peritumoural magnetic resonance imaging (MRI)-based radiomics nomogram for predicting tumour grade to improve clinical treatment and long-term prognosis. MATERIALS AND METHODS: MRI (3 T) features and T2-weighted imaging with fat-saturation (T2WI-FS)-based radiomics features of 57 patients with soft-tissue sarcoma (STS) were analysed retrospectively. Tumour size, ratio of width and length, relative depth to the peripheral fascia, peritumoural oedema, heterogeneity on T2WI, necrosis signal, enhancement model, and peritumoural enhancement were obtained. Independent risk factors were screened to construct an MRI feature nomogram. Radiomics features were obtained from intratumoural and peritumoural images on T2WI-FS. The optimal radiomics model was selected by the four-step dimensionality reduction method of minimum and maximum normalisation, optimal feature selection, selection based on support vector machine with L1-norm regularisation model, and iterative feature selection. MRI features and optimal radiomics features were used to construct a radiomics nomogram. The MRI feature nomogram model, the radiomics model, and the radiomics nomogram model were assessed by receiver operating characteristic (ROC) curves and calibration curves of the training and validation sets. RESULTS: Heterogeneity on T2WI and peritumoural enhancement were independent risk factors for predicting high-grade STS. The areas under the curves of the training set and verification set of the three models were as follows: MRI feature nomogram, 0.86 and 0.83, respectively; intratumoural and peritumoural combined radiomics model, 0.99 and 0.86, respectively; and radiomics nomogram model, 0.98 and 0.96, respectively. CONCLUSION: The radiomics nomogram model based on MRI features and combined intratumoural and peritumoural radiomic features was best able to predict high-grade STS.

[An investigation on the nutritional status and support of in-patients with common variable immunodeficiency].

The study aimed to reveal for the first time the clinical characteristics, nutritional and metabolic status and support of hospitalized patients with common variant immunodeficiency disease (CVID), and provide reference to improve the long-term nutritional management for such patients. This is a retrospective cross-sectional study. Through searching the electronic medical record system of Peking Union Medical College Hospital, the study included 33 consecutive in-patients with CVID diagnosed in Jan 2016 to Jun 2021, with the male to female ratio of 16∶17. All their medical data, nutritional assessment and intervention retrospectively summarized and analyzed. Data with normal distribution were described using (x¯±s), and analyzed with independent sample t-test. Data with non-normal distribution were compared with non-parametric test. The results showed that the median onset-age of the included patients was 22 (10.0,36.5) years old, and the median duration was 9.0 (2.0,16.0) years. All patients had recurrent infections involving various systems (33/33), with development of autoimmune diseases (8/33) and lymphoproliferative disease or malignancy (9/33) in some cases among them. The nutritional risk screening 2002 (NRS 2002) scores revealed that 85.19% of adults had an NRS 2002≥3 points, and 33.33% of children had a BMI-for-age z score<-2. Weight loss occurred in 66.67% of patients (22/33), while 87.88% (29/33), 69.70% (23/33) and 81.82% (27/33) of patients respectively had anemia, hypoalbuminemia and decreased prealbumin. Among 22 patients with micronutrients status evaluated, 77.27% (17/22), 22.73% (5/22) and 31.82% (7/22) of patients respectively had lowered serum iron, folate deficiency and vitamin B12 insufficiency. Six patients underwent 25-OH-VD3 measurement, and were all testified to have vitamin D deficiency. Among all patients with nutritional risk, 56.00% of them underwent nutritional support: oral nutritional supplements (14 cases), enteral feeding (4 cases) and parenteral nutrition (5 cases). In conclusion, the condition of malnutrition was prevalent in patients with CVID, but was under-recognized and undertreated to some degree.

[Study on related factors and characteristics of multimorbidity of overweight and obesity-related diseases in children in Hunan Province].

From January 2019 to December 2021, overweight and obese children who visited in health outpatient Center of Hunan Children's Hospital were studied to explore and analyze the rate, related factors and patterns of multimorbidity of overweight and obesity-related diseases in children in Hunan Province. Univariate and multivariate logistic regression models were used to analyze the multimorbidity-related factors of overweight and obesity-related diseases in children. Association rules (apriori algorithm) were used to explore the multimorbidity patterns of overweight and obesity-related diseases in children. A total of 725 overweight and obese children were included in this study. The multimorbidity rate of overweight and obesity-related diseases in children was 46.07% (334/725). Age, waist circumference, the frequency of food consumption such as hamburgers and fries and adding meals before bedtime were multimorbidity-related factors of overweight and obesity-related diseases in children. The multimorbidity associated with nonalcoholic fatty liver disease (NAFLD) was relatively common. The patterns with the top three support degrees were "NAFLD+dyslipidemia","NAFLD+hypertension" and "NAFLD+hyperuricemia". The patterns with the top three confidence and elevation degrees were "Hypertension+dyslipidemia => NAFLD","Hyperuricemia => NAFLD" and "NAFLD+hypertension => dyslipidemia".

[Efficacy comparison of minimally invasive atlantoaxial mass fusion and open atlantoaxial fusion in the treatment of atlantoaxial dislocation].

Objective: To compare the clinical effects of minimally invasive intermuscular atlantoaxial lateral mass fusion (Mis-PALF) and open atlantoaxial fusion in patients with atlantoaxial dislocation. Methods: The clinical data of patients with atlantoaxial dislocation who received Mis-PALF operation (17 cases) or open atlantoaxial fusion (88 cases, as control) in the Third Hospital of Peking University from September 2015 to September 2021 were analyzed retrospectively. In Mis-PALF group, there were 9 males and 8 females, aged (45.8±19.8) years; and there were 48 males and 40 females in the control group, aged (50.0±13.9) years. The operation time, perioperative blood loss, postoperative body temperature, postoperative pain [assessed with visual analogue scale (VAS)], postoperative additional analgesic drugs, postoperative hospitalization time, the improvement rate of Japanese Orthopedic Association (JOA) scores of spinal cord function in three-months follow-up and complications were compared between the two groups. Results: Mis-PALF group had less perioperative blood loss than control group [(111.8±35.9)ml vs (362.9±18.6)ml, P<0.01], shorter hospitalization time [(3.06±0.63) days vs (4.24±0.14) days, P<0.01] and fewer additional analgesic drugs (3/17 vs 56/88, P<0.01). There was no significant difference between the Mis-PALF and control group in operation time [(125±7)min vs (113±8)min, P=0.525], patients with fever(11/17 vs 37/88, P=0.086) or postoperative pain (1/17 vs 13/88, P=0.357), the improvement rate of JOA score (66.9%±28.8% vs 74.2%±28.6%, P=0.409) and complications rate (1/17 vs 3/88, P=1.000). Conclusion: Mis-PALF can significantly reduce the perioperative blood loss, shorten the postoperative hospitalization time and the additionally use of analgesic drugs without increasing complications.

[Impact of prolonging dual antiplatelet therapy on long-term prognosis of elderly patients with coronary heart disease complicated with diabetes mellitus undergoing drug-eluting stent implantation].

Objective: To explore and compare the effect of standard or prolonged dual antiplatelet therapy (DAPT) on the long-term prognosis of elderly patients with coronary heart disease complicated with diabetes mellitus after drug-eluting stent (DES) implantation. Methods: Consecutive patients with diabetes mellitus, ≥65 years old, underwent DES implantation, and had no adverse events within 1 year after operation underwent percutaneous coronary intervention (PCI) from January to December 2013 in Fuwai Hospital were enrolled in this prospective cohort study. These patients were divided into three groups according to DAPT duration: standard DAPT duration group (11 ≤ DAPT duration≤ 13 months) and prolonged DAPT duration group (1324 months). All the patients were followed up at 1, 6 months, 1, 2 and 5 years in order to collect the incidence of major adverse cardiovascular and cerebrovascular events (MACCE), and type 2 to 5 bleeding events defined by the Federation of Bleeding Academic Research (BARC). MACCE were consisted of all cause death, myocardial infarction, target vessel revascularization or stroke. The incidence of clinical adverse events were compared among 3 different DAPT duration groups, and Cox regression model were used to analyze the effect of different DAPT duration on 5-year long-term prognosis. Results: A total of 1 562 patients were enrolled, aged (70.8±4.5) years, with 398 female (25.5%). There were 467 cases in standard DAPT duration group, 684 cases in 1324 months group. The patients in standard DAPT duration group and the prolonged DAPT duration groups accounted for 29.9% (467/1 562) and 70.1% (1 095/1 562), respectively. The 5-year follow-up results showed that the incidence of all-cause death in 1324 month group(4.1%(17/411) vs. 8.6%(40/467),P=0.008) were significantly lower than in standard DAPT group. The incidence of myocardial infarction in 1324 month group were 19.3% (90/467), 12.3% (84/684), 20.2% (83/411), respectively, P<0.001). There was no significant difference in the incidence of stroke and bleeding events among the three groups (all P>0.05). Multivariate Cox analysis showed that compared with the standard DAPT group, prolonged DAPT to 13-24 months was negatively correlated with MACCE (HR=0.601, 95%CI 0.446-0.811, P=0.001), all-cause death (HR=0.568, 95%CI 0.357-0.903, P=0.017) and myocardial infarction (HR=0.353, 95%CI 0.179-0.695, P=0.003). DAPT>24 months was negatively correlated with all-cause death (HR=0.687, 95%CI 0.516-0.913, P=0.010) and positively correlated with revascularization (HR=1.404, 95%CI 1.116-1.765, P=0.004). There was no correlation between prolonged DAPT and bleeding events. Conclusions: For elderly patients with coronary heart disease complicated with diabetes mellitus underwent DES implantation, and had no MACCE and bleeding events within 1 year after operation, appropriately prolonging of the DAPT duration is related to the reduction of the risk of cardiovascular adverse events. Patients may benefit the most from the DAPT between 13 to 24 months. In addition, prolonging DAPT duration does not increase the incidence of bleeding events in this patient cohort.

[Effects of individual factors and labor organization on neck pain in auto assembler].

Objective: To investigate the influence of individual factors and labor organization on the prevalence of neck pain (hereinafter referred to as neck pain) in automotive assemblers, and to provide a basis for enterprises to optimize neck pain interventions. Methods: A cluster random sampling method was taken in January 2021, at an automobile manufacturing plant in Shiyan, 656 assemblers with ≥1.0 years of service were selected, the "Musculoskeletal Disorder Questionnaire" was used to investigate the incidence and influencing factors of neck pain. Pearson χ(2) test or trend χ(2) test was used to compare the data rates. The influencing factors of neck pain were analyzed by multivariate logistic regression. Results: The prevalence rate of neck pain (hereinafter referred to as the prevalence rate of neck pain) of automobile assemblers within one year was 53.94% (342/634) . The prevalence of neck pain in women was higher than that in men (69.1% vs 48.6%, P<0.01) . The prevalence of neck pain was related to length of service, self-assessment of fatigue, working hours per week, working in the same workshop, rest days per shift, and accumulated rest time per shift (P<0.05) . Multivariate logistic regression analysis showed that the risk of neck pain in women was 2.434 times higher than that in men; The risk of neck pain increased by 18.9% for each hour of work per week; Rest during work was a protective factor for neck pain. The number of rest per shift increased and the risk of neck pain decreased (r=0.405, 0.311, 0.302, 95%CI=0.205~0.803, 0.169~0.572, 0.142~0.642, P<0.05) . Conclusion: The annual prevalence of neck pain was higher in automobile assemblers. Enterprises should fully consider the influencing factors such as gender, working hours per week and the number of breaks when arranging production.

Directional massless Dirac fermions in a layered van der Waals material with one-dimensional long-range order.

One or a few layers of van der Waals (vdW) materials are promising for applications in nanoscale electronics. Established properties include high mobility in graphene, a large direct gap in monolayer MoS2, the quantum spin Hall effect in monolayer WTe2 and so on. These exciting properties arise from electron quantum confinement in the two-dimensional limit. Here, we use angle-resolved photoemission spectroscopy to reveal directional massless Dirac fermions due to one-dimensional confinement of carriers in the layered vdW material NbSi0.45Te2. The one-dimensional directional massless Dirac fermions are protected by non-symmorphic symmetry, and emerge from a stripe-like structural modulation with long-range translational symmetry only along the stripe direction as we show using scanning tunnelling microscopy. Our work not only provides a playground for investigating further the properties of directional massless Dirac fermions, but also introduces a unique component with one-dimensional long-range order for engineering nano-electronic devices based on heterostructures of vdW materials.

Differences in tumour heterogeneity based on dynamic contrast-enhanced MRI between tumour and peritumoural stroma for predicting Ki-67 status of invasive ductal carcinoma.

AIM: To evaluate and compare the heterogeneity of intratumour and peritumour areas in the prediction of Ki-67 of invasive ductal carcinoma (IDC) and the predictive accuracy of different contrast frames based on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). MATERIALS AND METHODS: This study included 88 patients with histologically confirmed IDC with 57 patients with high Ki-67 status and 31 patients with low Ki-67 status. All patients underwent DCE-MRI before surgery. A grey-level co-occurrence matrix (GLCM) was performed on slice-matched images from six frames by drawing the region of the interest (ROI) on the inner and outer regions of the tumours. The correlations between texture characteristics and Ki-67 status of lesions were analysed, using the Mann-Whitney test and receiver operating characteristic curve analysis. RESULTS: In the high-Ki-67 group, the entropy was significantly higher than that of the low-Ki-67 group (p<0.001). The entropy obtained, based on the tumour boundary as a band-like area inside and outside at the first post-contrast series, revealed the highest receiver operating characteristic (AUC = 0.765). In the multivariate analysis, a higher entropy value (>4.305; p<0.001) remained independently associated with a high-Ki-67 status after adjustment for menopausal status, tumour size, histologic grade, oestrogen receptor (ER) status, and progesterone receptor (PR) status. The other parameters did not show significant differences between the high- and low-Ki-67 groups. CONCLUSION: Heterogeneity analysis based on DCE-MRI could discriminate between high- and low-Ki-67 status. Texture characteristics from the band-like region inside and outside the tumour boundary could predict the Ki-67 status and showed higher accuracy.

Treatment and Outcome in Deficiency of Adenosine Deaminase 2: A Literature Review.

OBJECTIVES: Deficiency of adenosine deaminase 2 (DADA2) is a rare disease with varying phenotypes and disease outcomes. We evaluated the treatment of DADA2 and explored the factors associated with disease outcome. METHODS: A systemic literature review of DADA2 was conducted. Cases were included if they had documented detailed genotypes, phenotypes, treatment protocols, and outcomes. Patients were categorized as having uncontrolled and controlled disease. Factors associated with disease outcome were analyzed using logistic regression models. RESULTS: The study population comprised 242 DADA2 patients with data on treatment protocols and responses, of whom 17 required no treatment. Tumor necrosis factor a inhibitors (TNFi) were effective in 78.6% (103/131). Hematological abnormalities and increased acute phase reactants are independently associated with the effectiveness of TNFi (OR, 0.21 [95%CI, 0.07-0.661; P=.007] and 9.62 [95%CI, 2.31-40.00; P=.002, respectively). Among the 225 patients requiring active treatment, 157 (69.8%) had controlled disease and 68 (30.2%) uncontrolled disease. Neither age of disease onset nor genotype was associated with disease outcome. Increased acute phase reactant values, constitutional symptoms, neurological symptoms, and treatment with TNFi were independently associated with disease control, while recurrent infections and severe vascular events were the main causes of mortality (10/21 and 6/21, respectively). CONCLUSION: In patients requiring treatment, symptoms of systemic inflammation and vasculitis and treatment with TNFi are associated with disease control. Recurrent infections and severe vascular events should be treated intensively, as they are the main causes of death. Hematological abnormalities should be monitored, as they decrease the effectiveness of TNFi.

H-FABP gene expression and genetic association with meat quality traits in domestic pigeons (Columba livia).

1. H-FABP (heart-type fatty acid-binding protein) is an important fatty acid-binding protein that participates in the metabolism and intracellular transportation of lipids. This study was designed to study the H-FABP gene expression and genetic association with meat quality traits in domestic pigeons.2. The spatio-temporal expression patterns showed that H-FABP was widely expressed in all eleven tissues in birds from hatching to 4 weeks of age, and the expression level in the liver was the highest, and spleen and subcutaneous fat showed relatively high levels at all time points, and increased markedly as squabs became older.3. Nine novel SNPs were found; three of them (g.42 C > T and g.123 C > T in exon 1 and g.3128 C > T in exon 2) were synonymous mutations, and six of them (g.3304 T > C, g.3305 G > A, g.3313A>G, g.3343 C > T, g.3372A>C, g.3410 T > C in exon 3) were located in the 3' untranslated region (UTR). In addition, four haplotypes and six diplotypes were formed and showed weak linkage disequilibrium. Association analysis showed that in the SNP of g.3305 G > A, the AB genotype showed higher (P < 0.05) inosinic acid concentrations in breast muscle than the BB genotype. In the SNP of g.3313A>G, the AA and AB genotypes showed significantly higher (P < 0.01) inosinic acid concentrations than the BB genotype, AA showed the highest intramuscular fat content, and the relative mRNA expression level of the AA genotype was the highest (P < 0.05).4. Association analysis of diplotypes showed no correlation with meat quality traits. Moreover, correlation analysis indicated that the H-FABP mRNA expression level was tightly related to intramuscular fat content (P < 0.01).5. This study suggested that the H-FABP gene may be a candidate gene in marker-assisted selection of pigeons for high-quality meat.

[Digital and anatomical study of posterior atlantooccipital joint-occipital condyle-clivus screw technique].

Objective: To investigate the screw placement parameters, feasibility and safety of posterior atlantooccipital joint-occipital condyle-clivus screw technique in Chinese people. Methods: Upper cervical spine CT images of 46 patients, including 24 males and 22 females, were collected with random number table from June 2019 to May 2020 in Ningbo No.6 Hospital. The patients aged 20-55 years, with a mean age of (39±9) years. Total of 92 sides of upper cervical spine models were obtained by Mimics 19.0 digital three-dimensional reconstruction, and screw placement was conducted simulately. The midpoint of transition zone between the posterior arch of atlas and the inferior articular process of lateral mass was selected as the screw entry point. The diameter and length of screws was 3.5 mm and 50 mm, respectively. Detailed morphometric measurements of the 92 atlantooccipital joint-occipital condyle-clivus screws were conducted. The distance between the screw and its surrounding important structures, screw inside and upper tilting angles, the length of screw trajectory in atlas and the length of screw trajectory on occipital side (occipital condyle-clivus) were all measured. Paired t test was performed on the parameters of left and right screw placement to confirm whether there was difference between the two sides. Results: In the 46 cases of upper cervical spine digital three-dimensional models, 92 posterior atlantooccipital joint-occipital condyle-clivus screws were implanted. All the screws were completely fixed in the clivus, without breaking through the upper sphenoid sinus, entering into the canalis spinalis and foramen magnum, and damaging the surrounding structures such as hypoglossal canal. The screw trajectory parameters between the left and right sides were slightly different, but there was no statistical differences between the two sides (P>0.05). The vertical distance between the screw entry point and the upper edge of atlas was (12.6±1.0) mm, the vertical distance between the screw entry point and the lower edge of atlas was (6.5±0.6) mm, the distance between the screw and the medial border of atlas vertebral artery foramen was (6.7±0.6) mm, the distance between the screw entry point and the medial wall of atlas was (6.6±0.7) mm, the distance between the screw outer margin and the hypoglossal canal was (5.5±0.6) mm, screw inside tilting angle was 21.2°±2.5°, screw upper tilting angle was 52.0°±3.4°, the length of screw trajectory in atlas was (12.1±0.9) mm, the length of screw trajectory on occipital side (occipital condyle-clivus) was (37.9±0.9) mm. Conclusion: The posterior atlantooccipital joint-occipital condyle-clivus screw technique can serve as a feasible and safe treatment for instability of the occipitocervical junction, which can be used as a new posterior occipitocervical fusion technique.

[Analysis of the anatomical features of vestibular nerve canal based on 10 µm otology CT].

Objective: To analysis the anatomical features of normal vestibular nerve canal based on 10 µm otology CT. Methods: Sixty-seven patients (103 ears) underwent 10 µm otology CT examinations in Department of Radiology, Beijing Friendship Hospital, Capital Medical University from September 2020 to March 2021 were retrospectively recruited. There were 24 males and 43 females, aged from 18 to 70 (40±17) years. According to the morphology of the inferior vestibular nerve canal, it can be divided into four types as follows: uniform straight type, curved type, ampullary type and direct connection. The anatomical variables of the superior vestibular nerve canal (external orifice, isthmus and internal orifice widths, canal length, angle with labyrinthine segment of the facial nerve) and inferior vestibular nerve canal (widths of the externaland internal orifice, canal length, angles with long axis of the vestibule and the modiolus) between the different sides, genders and canal morphologies were analyzed and compared, respectively. Results: 100% superior vestibular nerve canals and 75.7% (78/103) inferior vestibular nerve canals are clearly depicted by otology CT. The left-side ear presented with larger internal orifice diameter of the superior vestibular neve canal [(1.46±0.47) mm vs (1.31±0.41) mm], and a smaller angle between the inferior vestibular neve canal and the modiolus [(41.6±16.9)° vs (51.6±21.0)°] than the right-side ear (all P<0.05, respectively), respectively. Compared to females, males demonstrated larger internal orifice of the superior vestibular nerve canal [(1.55±0.37) mm vs (1.28±0.36) mm, P<0.05]. The uniform straight type of the inferior vestibular nerve canal was the most common type (62.1%, 64/103), followed by the direct connection (19.4%, 20/103), and the ampullary type was the least common type (4.9%, 5/103). There were significant differences in external diameter and angles with the long axis of the vestibule and the modiolus between the four morphologies of the superior vestibular nerve canal (all P<0.05, respectively). Conclusion: Ten µm otology CT is capable of depicting normal vestibular nerve canal clearly. Quantitative measurement of the normal vestibular nerve canal can provide references for the imaging diagnosis and preoperative evaluation of lesions in this area.

[Analysis of spatial location of the malleus in patients with chronic otitis media based on 10 µm otology CT].

Objective: To assess the changes of the spatial location of the malleus in patients with chronic otitis media (COM) using 10 µm otology CT. Methods: Forty-five patients with COM (COM group, 45 ears) and 55 patients without external and middle ear disease (control group, 89 ears), who underwent 10 µm otology CT examination in Department of Radiology, Beijing Friendship Hospital, Capital Medical University from October 2020 to March 2021, were retrospectively collected during the same period. In the COM group, there are 20 males and 25 females, aged from 20 to 78 (40±14) years. In the control group, 29 were males and 26 were females, with age of 19 to 57 (32±11) years. The shortest distance between the malleus head and the upper wall, the distance between the outer edge of the malleus neck and the scutum, the distance between the outer edge of the malleus neck and the pars flaccida of the tympanic membrane, the shortest distance between the malleus head and the anterior wall, the shortest distance between the anterior process and the anterolateral wall, the shortest distance between the tip of the malleus handle and the promontory, and the shortest distance between the malleus head and the tympanic segment of the facial nerve were measured and compared between the two groups. Results: Compared with the control group, the head-upper wall distance (M (Q1, Q3)) (0.81 (0.48, 1.21) mm vs 0.57 (0.33, 0.90) mm) and the neck-scutum distance (1.79 (1.54, 2.13) mm vs 1.65 (1.48, 1.83) mm) were larger in the COM group (all P<0.05), and the neck-tympanic membrane distance (1.32 (1.15, 1.49) mm vs 1.45 (1.31, 1.59) mm) and the handle-promontory distance (1.56 (1.33, 2.09) mm vs 2.10 (1.74, 2.43) mm) were reduced in the COM group (all P<0.05, respectively). The neck-tympanic membrane distance on the left was larger than those on the right in the COM group (1.39 (1.19, 1.51) mm vs 1.21 (0.87, 1.31) mm, P<0.05). Conclusion: There are changes in the relative position of the malleus in patients with COM, which are helpful for further understanding the imaging manifestations in patients with COM.

[Application of 10 µm otology CT on evaluation of isolated malleus fixation in patients with conductive hearing loss].

Objective: To evaluate the application of 10 µm otology CT on evaluation of isolated malleus fixation (IMF) in patients with conductive hearing loss. Methods: A total of 19 patients (25 sides) with idiopathic hearing loss, including 8 males and 11 females, aged between 4 to 50 years, who underwent 10 µm otology CT examination in Department of Radiology, Beijing Friendship Hospital, Capital Medical University from October 2020 to July 2021, were retrospectively collected. For those patients with idiopathic hearing loss, there were 5 cases (6 sides), including 2 males and 3 females, with an average age of 18-70 [65(20,68)] years, with bony connection between malleus and tympanum wall. Eighteen sex-and age-matched cases with normal hearing group, including 6 males and 12 females, with an average age of 20-68 (39±14) years, as the ratio of 1∶3, were included as the controls. The distances of the tegmen tympani between malleus head and horizontal semicircular canal, as well the distances between malleus head and horizontal semicircular canal were retrospectively measured and further compared between the two groups. Results: The incidence of IMF in patients with idiopathic conductive hearing loss without other etiologies was 24.0% (6/25). The specificity of 10 µm otology CT in diagnosing IMF was 100%. The distances of tegmen tympani between horizontal semicircular canal and malleus head in IMF patients were significantly smaller compared with the controls [-0.65(-1.21, -0.35) mm vs 1.34(0.04, 1.68) mm;0.92(0.51, 1.49) mm vs 2.82(1.76, 3.53) mm](both P<0.05, respectively). There was no significant difference in distances between malleus head and horizontal semicircular canal [-1.30 (-1.90, -0.46)mm vs -0.42 (-1.15, 0.05),P=0.057]. Conclusions: IMF is not uncommon in conductive hearing loss without other causes, which can be clearly shown by 10 µm otology CT. Its occurrence is related to the local downward shift of tegmen tympani above the malleus, without upwards displacement of the malleus.

[Experimental comparison of temporal bone imaging protocol optimization between 10 µm otology CT and multi-slice CT].

Objective: To evaluate different protocol optimization strategies for temporal bone between10 µm otology CT and multi-slice CT (MSCT). Methods: Ten adult skull specimens (20-sides temporal bones) were prospectively enrolled. From October to November 2020, the temporal bones were scanned under four different imaging conditions using 10 µm otology CT (90 kV, 120 mAs; 90 kV, 140 mAs; 100 kV, 120 mAs; 100 kV, 140 mAs) and MSCT (120 kV, 220 mAs; 120 kV, 310 mAs; 140 kV, 160 mAs; 140 kV, 220 mAs), respectively. The image quality was subjectively scored using 5-grade scores, and the contrast noise ratio (CNR) of the image was measured. The absorbed dose of tissues and organs under different imaging conditions was measured by thermoluminescence dosimeter, and the effective dose was calculated. The figure of merit (FOM) is defined as the ratio of the square of the mean CNR to the effective dose. χ2 test was used to compare the difference of subjective scores of different scanning parameter groups, and paired t test was used to analyze and compare the difference of image CNR of different scanning parameter groups. The image quality, radiation dose and FOM of the combination of recommended parameters of the two devices were analyzed and compared. Results: For 10 µm otology CT, under 100 kV condition, the CNR of 140 mAs group was better than that of 120 mAs group (11.27±1.85 vs 10.26±1.38, P<0.001). There was no significant difference in subjective scores between the two groups [5.00 (4.00, 5.00) vs 5.00 (4.25, 5.00), P=0.264]. For MSCT, under 120 kV condition, the subjective scores and CNR of 310 mAs group were better than those of 220 mAs at 120 kV [4.00(3.00, 4.00) vs 3.00(3.00, 3.00),P=0.002;5.24±0.62 vs 4.60±0.62,P<0.001]. According to the principle of image quality-radiation dose optimization, the combination of 100 kV with 120 mAs and 120 kV with 310 mAs are recommended for 10 µm otology CT and MSCT, respectively. The subjective scores and CNR of 10 µm otology CT images were better than those of MSCT (5.00 (4.25, 5.00) vs 4.00 (3.00, 4.00), 10.26±1.38 vs 5.48±0.22, P<0.001). The effective dose was 1/3 of that of MSCT (82.99 µSv vs 252.56 µSv), and the FOM was 11.16 times of that of MSCT (1 268.44 mSv-1 vs 113.71 mSv-1). Conclusion: The temporal bone image quality of newly developed 10 µm otology CT is significantly better than that of MSCT, and its effective dose is lower than that of MSCT, which has more accurate and safer application potential.

[Study on the relationship between the morphology of the isthmus of the vestibular aqueduct and Meniere's disease based on 10 µm otology CT].

Objective: To evaluate the morphology of isthmus of the vestibular aqueduct (VA) and its relationship with the occurrence, course of Meniere's disease (MD) and the degree of hearing loss based on 10 µm otology CT. Methods: A total of 13 patients with MD in Beijing Friendship Hospital, Capital Medical University from October 2020 to July 2021, including 4 males and 9 females, age from 16 to 77 (56±16) years, were prospectively enrolled. All patients underwent 10 µm otology CT examination. The included lesion side was the MD affected group (14 sides), and the non-lesion side was the MD healthy group (12 sides). According to the 1∶2 side, 16 sex-and side matched cases (28 sides) without external and middle ear disease were included in the control group, including 4 males and 12 females, age from 16 to 77 (56±14) years. The horizontal semicircular canal showed on the largest plane was considered as the standard cross-section, and continuous observation was made on this image. According to the display type of isthmus of the VA, it was divided into Ⅰ to Ⅳ grades. Kruskal Wallis test was used to compare the morphological differences of VA isthmus among the affected group, the healthy group and the control group. The degree of hearing impairment was assessed by pure tone audiometry (PTA) results, which were divided into normal/mild/moderate/moderately severe/severe/extremely severe hearing impairment. Spearman correlation analysis was used to compare the correlation between the morphological rating of VA isthmus on the affected side and age, course of disease and the results of pure tone audiometry (PTA). Results: The proportions of VA isthmic morphology GRADE Ⅰ,Ⅱ,Ⅲ,Ⅳ in the MD affected group were 28.6% (4/14), 42.9% (6/14), 21.4% (3/14), 7.1% (1/14), those in the MD healthy group were 0 (0/12), 33.3% (4/12), 33.3% (4/12), 33.3% (4/12), and those in the control group were 0 (0/28), 7.1% (2/28), 64.2% (18/28), 28.6% (8/28). The VA isthmus scores [M (Q1, Q3)] of MD affected group was lower than that of MD healthy group [2 (1, 3) vs 3 (2, 4)] and control group [2 (1, 3) vs 3 (3, 4)] (all P<0.05, respectively). The morphology of the VA isthmus on the affected side of MD was negatively correlated with age (r=-0.81, P=0.002), and there was no correlation with the course of disease and degree of hearing impairment (r=-0.40, r=-0.26; all P>0.05, respectively). Conclusion: The stenosis of the VA isthmus in MD was a possible anatomical factor for the occurrence of MD.

[Analysis of the imaging characteristics of otosclerosis based on 10 µm otology CT].

Objective: To evaluate the imaging features of otosclerosis based on10 µm otology CT. Methods: Data of 27 patients with otosclerosis (51 sides) in Beijing Friendship Hospital, Capital Medical University from October 2020 to July 2021 were retrospectively collected, including 9 males and 18 females age ffrom 22 to 70 (42±12) years. All patients underwent 10 µm otology CT examination and surgical treatment. The types, amounts and involved sites of otosclerosis were analyzed and the sensitivity of 10 µm otology CT in diagnosing otosclerosis were evaluated. Results: Fenestral type accounted for 49.0% (25/51 sides), and diffuse type accounted for 51.0% (26/51 sides),and he retrofenestral type without fenestral lesion was not seen. Single lesions accounted for 45.1% (23/51 sides) and multiple lesions accounted for 54.9% (28/51 sides). The incidence of involvement of the fissula ante fenestram and annular ligaments were both 100%. The incidence of involvement of stapes footplate, vestibule, cochlea, round window, inner auditory canal wall, facial nerve canal, stapes muscle and semicircular canal was 60.8% (31 sides), 33.3% (17/51 sides), 21.6% (11/51 sides), 17.6% (9/51 sides), 13.7% (7/51 sides), 9.8% (5/51 sides), 7.8% (4/51 sides) and 5.9% (3/51 sides), respectively. The sensitivity of 10 µm otology CT in diagnosis of otosclerosis was 100%. Conclusion: 10 µm otology CT can fully display the imaging features of otosclerosis, and has the potential to be an effective routine method for otosclerosis.