Objective:To compare the efficacy of inverted triangular and equilateral triangular cannulated screw internal fixation (CSIF) in the treatment of femoral neck fracture (FNF) in young and middle-aged patients.Methods:A retrospective cohort study was conducted to analyze the clinical data of 52 patients with FNF admitted to Qingdao Central Hospital of Rehabilitation University from January 2020 to January 2022, including 18 males and 34 females, aged 28-60 years [(45.7±9.3)years]. Based on the Garden classification, the fractures were classified as type I in 11 patients, type II in 34, and type III in 7. According to Pauwels classification, the fractures were classified as type I in 33 patients, type II in 13, and type III in 6. Among them, 28 patients received inverted triangular CSIF (inverted triangle group) and 24 received equilateral triangular CSIF (equilateral triangle group). Before surgery and at 3 months after surgery, nuclear medicine three-phase bone scan and bone tomography imaging were performed to evaluate the proximal blood supply recovery in the fractured sites in the two groups. The Harris hip joint function scores before surgery, at 1 day, 3 months after surgery, and at the last follow-up, the posterior tilt angles of the femoral head before surgery and at 3 months after surgery, and the fracture nonunion rate and ischemic necrosis rate of the femoral head at the last follow-up were compared between the two groups.Results:All the patients were followed up for 18-30 months [(24.2±5.6)months]. Before surgery, the fracture of both groups showed extensive blood supply defects at the proximal end. At 3 months after surgery, the excellent and good rate of the proximal blood supply recovery in the inverted triangle group was 92.9% (26/28), significantly higher than 70.8% (17/24) in the equilateral triangle group ( P<0.05). The Harris hip joint function scores before surgery were (44.1±4.1)points and (43.5±5.1)points in the inverted triangle group and equilateral triangle group ( P>0.05). At 1 day, 3 months after surgery, and at the last follow-up, the Harris hip joint function scores in the inverted triangle group were (71.7±3.6)points, (87.0±3.6)points, and (88.7±2.6)points respectively, higher than those in the equilateral triangle group [(65.0±5.4)points, (80.5±5.2)points, and (82.6±4.0)points] ( P<0.05). In both groups, there were no significant differences between the Harris hip joint function scores at the last follow-up and those at 3 months after surgery ( P>0.05), which were all higher than those at 1 day after surgery ( P<0.05). The posterior tilt angles of the femoral head were (16.9±4.4)° and (16.8±5.0)° in the inverted triangle group and equilateral triangle group preoperatively ( P>0.05). At 3 months after surgery, the posterior tilt angles of the inverted femoral head were (8.9±1.9)° and (9.0±1.8)° in the inverted triangle group and equilateral triangle group ( P>0.05). The posterior tilt angles of the femoral head at 3 months after surgery were lower than those before surgery in both groups ( P<0.05). At the last follow-up, there were no statistically significant differences in the fracture nonunion rate and ischemic necrosis rate of the femoral head between the two groups ( P>0.05). Conclusion:Compared with equilateral triangle CSIF, inverted triangle CSIF achieves better recovery of the proximal blood supply and hip joint function in the treatment of femoral neck fracture in young and middle-aged patients.

Objective:To study the incidence and epidemiological characteristics of tsutsugamushi disease in Ankang City, Shaanxi Province.Methods:From 2018 to 2023, data on tsutsugamushi disease cases reported by various medical institutions at all levels in Ankang City were collected through the China Disease Prevention and Control Information System. At the same time, individual epidemiological investigation of reported cases was carried out, and electronic medical records of patients were retrieved to verify their diagnosis. In 2023, the rodents and chigger mites were monitored in 3 townships with high incidence of tsutsugamushi disease in Ankang City by night clamping method, and the chigger mites rate and chigger mites index were calculated. Blood, liver, spleen and kidney samples of rodents were collected, DNA of blood and organ mixture was extracted, and quantitative real-time PCR was used to detect Orientia tsutsugamushi. Results:A total of 330 cases of tsutsugamushi disease were reported in Ankang City from 2018 to 2023, and the reported incidence rate increased from 0.56/100 000 in 2018 to 5.02/100 000 in 2023. Among them, 139 were males and 191 were females, with a sex ratio of 0.73∶1.00. The age was mainly 45 - 70 years old, accounting for 81.52% (269/330). The occupation was mainly farmers, accounting for 86.97% (287/330). The onset time was mainly concentrated from April to October, with a total of 317 cases, accounting for 96.06% (317/330). The main clinical manifestations were fever (93.20%, 274/294), ulcer or eschar (75.85%, 223/294), headache (44.56%, 131/294), and lymph node enlargement (44.22%, 130/294). The misdiagnosis rate at the first diagnosis was 73.81% (217/294). A total of 452 rodents were captured, of which 91 rodents carried chigger mites, and chigger mites rate was 20.13% (91/452). A total of 1 463 chigger mites were captured, and the chigger mites index was 3.24 (1 463/452). Quantitative real-time PCR was performed on blood and organ mixture samples collected from 452 rodents, and one of the organ mixture samples tested positive for Orientia tsutsugamushi. Conclusions:The incidence of tsutsugamushi disease in Ankang City is relatively high, and the overall incidence is on the rise. The cases are mainly female, middle-aged and elderly, and farmers, with a high misdiagnosis rate at the first diagnosis. There are chigger mites in rodents in townships with high incidence of tsutsugamushi disease.

Objective:To study the incidence and epidemiological characteristics of tsutsugamushi disease in Ankang City, Shaanxi Province.Methods:From 2018 to 2023, data on tsutsugamushi disease cases reported by various medical institutions at all levels in Ankang City were collected through the China Disease Prevention and Control Information System. At the same time, individual epidemiological investigation of reported cases was carried out, and electronic medical records of patients were retrieved to verify their diagnosis. In 2023, the rodents and chigger mites were monitored in 3 townships with high incidence of tsutsugamushi disease in Ankang City by night clamping method, and the chigger mites rate and chigger mites index were calculated. Blood, liver, spleen and kidney samples of rodents were collected, DNA of blood and organ mixture was extracted, and quantitative real-time PCR was used to detect Orientia tsutsugamushi. Results:A total of 330 cases of tsutsugamushi disease were reported in Ankang City from 2018 to 2023, and the reported incidence rate increased from 0.56/100 000 in 2018 to 5.02/100 000 in 2023. Among them, 139 were males and 191 were females, with a sex ratio of 0.73∶1.00. The age was mainly 45 - 70 years old, accounting for 81.52% (269/330). The occupation was mainly farmers, accounting for 86.97% (287/330). The onset time was mainly concentrated from April to October, with a total of 317 cases, accounting for 96.06% (317/330). The main clinical manifestations were fever (93.20%, 274/294), ulcer or eschar (75.85%, 223/294), headache (44.56%, 131/294), and lymph node enlargement (44.22%, 130/294). The misdiagnosis rate at the first diagnosis was 73.81% (217/294). A total of 452 rodents were captured, of which 91 rodents carried chigger mites, and chigger mites rate was 20.13% (91/452). A total of 1 463 chigger mites were captured, and the chigger mites index was 3.24 (1 463/452). Quantitative real-time PCR was performed on blood and organ mixture samples collected from 452 rodents, and one of the organ mixture samples tested positive for Orientia tsutsugamushi. Conclusions:The incidence of tsutsugamushi disease in Ankang City is relatively high, and the overall incidence is on the rise. The cases are mainly female, middle-aged and elderly, and farmers, with a high misdiagnosis rate at the first diagnosis. There are chigger mites in rodents in townships with high incidence of tsutsugamushi disease.

Objective:To compare the efficacy of inverted triangular and equilateral triangular cannulated screw internal fixation (CSIF) in the treatment of femoral neck fracture (FNF) in young and middle-aged patients.Methods:A retrospective cohort study was conducted to analyze the clinical data of 52 patients with FNF admitted to Qingdao Central Hospital of Rehabilitation University from January 2020 to January 2022, including 18 males and 34 females, aged 28-60 years [(45.7±9.3)years]. Based on the Garden classification, the fractures were classified as type I in 11 patients, type II in 34, and type III in 7. According to Pauwels classification, the fractures were classified as type I in 33 patients, type II in 13, and type III in 6. Among them, 28 patients received inverted triangular CSIF (inverted triangle group) and 24 received equilateral triangular CSIF (equilateral triangle group). Before surgery and at 3 months after surgery, nuclear medicine three-phase bone scan and bone tomography imaging were performed to evaluate the proximal blood supply recovery in the fractured sites in the two groups. The Harris hip joint function scores before surgery, at 1 day, 3 months after surgery, and at the last follow-up, the posterior tilt angles of the femoral head before surgery and at 3 months after surgery, and the fracture nonunion rate and ischemic necrosis rate of the femoral head at the last follow-up were compared between the two groups.Results:All the patients were followed up for 18-30 months [(24.2±5.6)months]. Before surgery, the fracture of both groups showed extensive blood supply defects at the proximal end. At 3 months after surgery, the excellent and good rate of the proximal blood supply recovery in the inverted triangle group was 92.9% (26/28), significantly higher than 70.8% (17/24) in the equilateral triangle group ( P<0.05). The Harris hip joint function scores before surgery were (44.1±4.1)points and (43.5±5.1)points in the inverted triangle group and equilateral triangle group ( P>0.05). At 1 day, 3 months after surgery, and at the last follow-up, the Harris hip joint function scores in the inverted triangle group were (71.7±3.6)points, (87.0±3.6)points, and (88.7±2.6)points respectively, higher than those in the equilateral triangle group [(65.0±5.4)points, (80.5±5.2)points, and (82.6±4.0)points] ( P<0.05). In both groups, there were no significant differences between the Harris hip joint function scores at the last follow-up and those at 3 months after surgery ( P>0.05), which were all higher than those at 1 day after surgery ( P<0.05). The posterior tilt angles of the femoral head were (16.9±4.4)° and (16.8±5.0)° in the inverted triangle group and equilateral triangle group preoperatively ( P>0.05). At 3 months after surgery, the posterior tilt angles of the inverted femoral head were (8.9±1.9)° and (9.0±1.8)° in the inverted triangle group and equilateral triangle group ( P>0.05). The posterior tilt angles of the femoral head at 3 months after surgery were lower than those before surgery in both groups ( P<0.05). At the last follow-up, there were no statistically significant differences in the fracture nonunion rate and ischemic necrosis rate of the femoral head between the two groups ( P>0.05). Conclusion:Compared with equilateral triangle CSIF, inverted triangle CSIF achieves better recovery of the proximal blood supply and hip joint function in the treatment of femoral neck fracture in young and middle-aged patients.

In order to help the standardized residency training of nuclear medicine residents, the standardized residency training base of nuclear medicine residents in Peking University People's Hospital, combined with forty-five nuclear medicine departments of teaching hospital, established the WeChat official account of "Standardized Residency Training of Nuclear Medicine" and submitted one teaching case per week. The appearance of the WeChat official account of "Standardized Residency Training of Nuclear Medicine" has made up for the shortcomings of insufficient teaching cases in a single training base, strengthened the training of residents' imaging diagnostic thinking, and promoted mutual learning among the bases. By writing teaching cases, instructors and residents have opened up ideas, increased knowledge, improved self-learning ability, and cultivated imaging diagnostic thinking. With the flexible and practical features of the WeChat official account, the consciousness and sustainability of residents' learning have been enhanced.

Objective:To further understand the etiological distribution of fever of unknown origin (FUO) in patients underwent 18F-fluorodeoxyglucose (FDG) PET/CT imaging, and to explore the significance of 18F-FDG PET/CT in the diagnosis of different types of diseases in FUO patients. Methods:From January 2013 to August 2019, the clinical and PET/CT image data of 466 FUO patients (194 males, 272 females, age: 3-91(52.7±20.9) years) in Peking University People′s Hospital were retrospectively analyzed. The etiological distribution of FUO patients was analyzed according to the final clinical diagnosis. PET/CT imaging manifestations were analyzed for different types of diseases in FUO patients. The role of 18F-FDG PET/CT in differential diagnosis for FUO was evaluated through clinical questionnaire. Data were analyzed by using χ2 test. Results:The common disease types in FUO patients were rheumatic and immune disease (48.7%, 227/466), infection (28.5%, 133/466) and malignant tumor (11.2%, 52/466). For PET/CT imaging, 95.5% (445/466) of the patients were positive, of which 313 (70.3%, 313/445) were found to have focal lesions, and the other 132 (29.7%, 132/445) showed only nonspecific abnormal uptake. Lesions in different types of diseases were varied in the location, morphological changes as well as FDG uptake. The results of the questionnaire showed that PET/CT imaging could benefit 95.9% (447/466) of the patients in the FUO diagnosis and treatment. PET/CT reached direct etiological diagnosis of malignant tumors more frequently than other types of diseases ( χ2 values: 14.408-25.466, all P<0.001). PET/CT helped or directly reached the etiological diagnosis of rheumatologic diseases more frequently than infection and unknown cause group( χ2 values: 7.922, 9.647, both P<0.05). Conclusion:18F-FDG PET/CT imaging has high clinical value in the diagnosis of FUO etiology and can provide multilevel diagnostic information.

Objective To explore 18F-FDG PET/CT characteristics of extramedullary relapse in patients with acute leukemia (AL).Methods Thirty AL patients with extramedullary relapse were retrospectively evaluated.The infiltrated organs or tissues and the maximum standardized uptake value (SUVmax) were recorded and compared between patients with acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML).FDG uptake pattern of bone marrow was also recorded.Results Forty-five extramedullary lesions were found in 16 ALL patients,while 29 were found in 14 AML patients.The average SUVmax was 7.38±4.46 in ALL patients and 4.87±2.66 in AML patients (t=3.022,P=0.003).Among ALL patients,lymph node and soft tissue involvement were detected each in 10,with SUVmax of 6.38 ± 3.55 and 10.12± 5.48,respectively.Among AML patients,lymph node and soft tissue involvement were detected in 6,with SUVmax of 4.82 ±1.43 and 6.60±4.58,respectively (P＞0.05).Multiple focal bone marrow uptakes of FDG were found in 5 of 5 intramedullary recurrence ALL patients and 2 of 5 intramedullary recurrence AML patients.The other 3 intramedullary recurrence AML patients showed diffuse bone marrow uptake.Conclusion There are certain imaging characteristics of 18 F-FDG PET/CT in extramedullary relapse of AL.The common relapse sites are lymph node and soft tissues in both ALL and AML.FDG uptakes of extramedullary relapse lesions in ALL are significantly higher than those of AML.Multiple focal bone marrow uptake of FDG is valuable in predicting intramedullary recurrence.

Objective To explore the MRI diagnostic value for pernicious placental abnormalities.Methods MRI findings of 1 5 patients with pernicious placenta previa were retrospectively analyzed after cesarean section.Results Among all cases,total placenta previa was,1 1 cases and partial placenta previa was 4 cases.The placenta located in the anterior wall in 8 cases,posterior wall in 4 cases,lateral wall in 3 cases.4 cases were diagnosed as normal placenta,6 cases as adhesion,4 cases as implanted,and 1 case as penetrating.These cases had certain special MR features.Conclusion MRI is helpful in diagnosing the location and type of the perni-cious placenta,and showing whether complicated with previa implantation and penetrating.

Objective To investigate the value of 99Tcm-MDP imaging for the differential diagnosis between infection and aseptic loosening after total hip arthroplasty.Methods During February 2008 to August 2011,74 patients (32 males,42 females,average age (64.3±11.2) years) with hip pain after arthroplasty underwent 3-phase (blood flow,blood pool and bone phases) 99Tcm-MDP imaging.All patients had measurements of serum C reactive protein (CRP) and erythrocyte sedimentation rate (ESR).Joint infection was defined as either increased peri-prosthetic soft tissue activity during perfusion and blood pool phases or increased peri-prosthetic bone activity during uptake phase,or positive in all 3 phases.Aseptic loosening was defined as having negative 99Tcm-MDP in all 3 phases.Clinical diagnosis was chosen as the gold standard.The blood flow-pool imaging was compared with the serum examinations.x2 test was used for statistical analysis.Results There were 74 symptomatic joints in 74 patients,including 24 joint infections and 50 aseptic loosening.For the detection of peri-prosthetic infection,combined perfusion-blood-pool phase was more accurate than bone uptake phase (90.5％ (67/74) vs 55.4％ (41/74) ;x2=23.159,P＜0.001),with the sensitivity of 91.7％ (22/24)vs 70.8％ (17/24) and specificity of 90.0％ (45/50) vs 48.0％ (24/50),respectively.The blood flow-pool imaging was also more accurate than CRP (73.0％ (54/74) ;x2 =7.656,P＜0.05) and ESR (71.6％ (53/74) ; x2 =8.633,P＜0.05),respectively.Conclusion 99Tcm-MDP perfusion/blood flow-pool imaging is an accurate modality for differentiating peri-prosthetic infection from aseptic loosening in patients with hip pain after arthroplasty.

Objective To explore the characteristics of MR perfusion imaging in normal pancreas and pancreatic cancer.Methods 20 cases of normal pancreas(without pancreatic diseases)and 20 cases with pancreatic cancer,underwent MR perfusion imaging using PHILIPS 1.5T unit with T1WI 3DFFE.12?4 collimation, 4 mm slice thickness ,20ml Gadopentetic Acid Dimeglumine 0.5mmol/ml Magnevist were used, the flow rate was 3.5 ml/s with a power injection,5 seconds delay,and data acquisition lasted for 90 seconds.These data were processed on a View Forum workstation using MR Brest Imaging(in Qualitity Analysis)software package ,and the mean maximum relative enhancement,wash in rate, wash out rate, time to peak, time of arrival and area under the curve were measured and statistically analyzed.Results The data of perfusion imaging in normal pancreas and carcinous pancreas were as followed respectively:maximum relative enhancement 95.69% and 50.74%,wash in rate 19.511/s and 4.471/s,wash out rate 26.051/s and 19.151/s,time to peak 31.33 s and 106.84 s,time of arrival 20.53 s and 64.70 s,area under the curve 15924.56 ml/(min? kg) and 5542.85 ml/(min ?kg).t-test showed that the difference of the perfusion data between normal pancreas and carcinous pancreas were significant(P