Objective To analyze the layout and shielding effectiveness of medical accelerator vaults, and to provide a reference for the layout, shielding design, and optimization of protection of medical accelerator vaults. Methods Four medical accelerator radiotherapy vaults were selected. The layouts of these vaults were compared with the layout requirements in the radiation therapy protection standards. For each vault, the dose rates at four points of interest outside the shielding were calculated, including the primary shielding area, secondary shielding area, maze outer wall, and lateral shielding area. These values were then compared with the actual measurements obtained using a dose rate meter. Results All four vaults were located on the ground floor of the building and included a maze, with the auxiliary rooms all placed outside the treatment rooms. However, one vault was not located at one end of the building, and in another vault, the control room was exposed to direct irradiation of the useful beam. The calculated dose rates outside the primary shielding area ranged from 0.04 μSv/h to 0.62 μSv/h, while the measured values ranged from 0.10 μSv/h to 0.66 μSv/h, with the measured values being higher than the calculated ones. The calculated dose rates outside the secondary shielding area ranged from 0.0005 μSv/h to 0.12 μSv/h, those outside the maze outer wall ranged from 0.06 μSv/h to 0.18 μSv/h, and those outside the lateral shielding area ranged from 0.009 μSv/h to 0.15 μSv/h; the measured values were all below the detection limit. Conclusion Inadequate layouts were observed in some of the accelerator vaults. The calculated and measured dose rates at points of interest outside the vaults were both significantly lower than the shielding protection requirements in standards, indicating that the shielding designs were overly conservative. Construction units should follow the principle of optimization of radiation protection to design the layout and shielding reasonably and pay attention to the underestimation of dose rates outside the primary shielding caused by the tenth value layer.

Objective To evaluate the ambient dose equivalent rates of photons and neutrons inside and outside the door of a 10 MV accelerator room, and to report the shielding effect of boron-containing polyethylene as maze wall lining. Methods The ambient dose equivalent rates of photons and neutrons inside and outside the door of an accelerator room were taken as the research subject. The Kersey, Falcão, and modified Kersey methods were used to calculate the ambient dose equivalent rates of neutrons and neutron capture gamma rays inside and outside the door of the room before and after renovation. Measurements were made using an X-ray/γ-ray dose rate instrument and a neutron ambient dose equivalent rate meter. Calculated and measured results were compared. Results Before renovation, the measured neutron dose rate inside the door was 409 μSv/h, while the calculated values were 323 μSv/h (Kersey method), 428 μSv/h (Falcão method), and 219 μSv/h (modified Kersey method). The Falcão method yielded a value closest to the measured value, while the Kersey and the modified Kersey methods underestimated the value by 21% and 46%, respectively. After the installation of boron-containing polyethylene plates, the measured neutron dose rate inside the door was 190 μSv/h, with a 54% reduction. The neutron and photon ambient dose equivalent rates outside the door were 5.8 μSv/h and 6.0 μSv/h, respectively, before renovation, and 0.14 μSv/h and 1.6 μSv/h, respectively, after renovation. Conclusion For a 10 MV accelerator room, neutron shielding and protection measurements are necessary, especially for rooms with short mazes. The Falcão method provides the best estimate of neutron dose rates inside and outside the door. Using boron-containing polyethylene plates as maze wall lining is an economical and effective shielding method.

In recent years,cardiovascular MRI(CMRI)technology has made significant advances,and multimodal CMRI imaging has been useful to display anatomical structure of the valves,to assess the severity of valvular disease,and to quantify the volume of cardiac chambers and myocardial fibrosis,as well as led to progress in judging mitral stenosis,mitral valve closure insufficiency,and risk stratification.Hence they have been widely used in the assessment of mitral valve lesions.The research progresses of CMRI for assessing mitral valve lesions were reviewed in this article.

Objective:To investigate the clinical and cardiac magnetic resonance (CMR) characteristics of heart involvement in patients with Fabry disease (AFD).Methods:From January 2018 to March 2021, eight AFD patients [3 males and 5 females, mean age (50±11) years old, range 26-60 years old] confirmed by genetic testing or pathology in Fuwai Hospital were retrospectively included in this study. At the same time, sixteen patients with hypertrophic cardiomyopathy (HCM) [6 males and 10 females, mean age (46±15) years old] and 16 healthy individuals [6 males and 10 females, mean age (51±11) years old] were included as controls. The clinical baseline data and CMR data of the patients were collected and analyzed. The CMR data were analyzed using the software CVI42, with the corresponding parameters automatically generated. One-way ANOVA or Kruskal-Wallis test was used to compare the differences in the parameters among the three groups. Independent-samples t test, Fisher precise test or Mann-Whitney U test were used for the comparison between each two groups. Results:Statistically significant difference was found in renal insufficiency between the HCM group and the AFD group; No other significant difference was found in other clinical factors and ECG results (all P>0.05). CMR results showed that in the AFD group, there were 5 cases with symmetric or roughly symmetric hypertrophy, and 3 with asymmetric hypertrophy. The late gadolinium enhancement (LGE) showed myocardial enhancement in 5 patients, mainly presenting as multiple intermural enhancement, and partially as local subendocardial enhancement. In the HCM group, fourteen cases suffered mainly asymmetric ventricular septal thickening, with or without thickening of other parts of left ventricular wall; and 2 cases had thickening of middle and distal part of the left ventricle. The LGE showed myocardial enhancement in 14 patients, which manifested as focal or patchy enhancement in hypertrophic myocardium, including focal enhancement in the right ventricular insertion of ventricular septum (more common) and subendocardial enhancement in the middle and far segments of left ventricle. Statistically significant difference was found in the differences between the left atrial anterior posterior diameter, the maximum wall thickness of left ventricular, the left ventricular myocardial mass index (LVMI) and the native T 1 value among the three groups (all P<0.001). However, there was no statistically significant difference in the left atrial anterior posterior diameter and the maximum wall thickness of left ventricular between AFD group and HCM group ( P>0.05). The LVMI in AFD group was higher than that in healthy group and HCM group (all P<0.05). Significant difference was found in the native T 1 value among the three groups, with the native T 1 value of the AFD group [(1 177.4±46.0) ms] was significantly lower than that of the healthy group [(1 244.5±34.3) ms] and the HCM group [(1 278.8±41.6) ms], with ( F=13.10, P<0.001). Conclusions:The clinical characteristics of AFD and HCM are quite similar. When AFD is suspected, CMR imaging should be the first choice for imaging examination. Especially, T 1 mapping imaging can provide important information for the diagnosis of AFD.

Objective: To compare the imaging characteristics and long-term prognosis in hypertrophic cardiomyopathy(HCM) patients with or without left ventricular apical aneurysm(LVAA). Methods: Retrospectively analyzed the clinical data from 18 patients diagnosed as HCM complicating with LVAA(HCM-LVAA group), hospitalized and underwent cardiac magentic resonance (CMR) examination in Fuwai Hospital between December 2012 and December 2016. Eighteen age and gender matched patients with HCM diagnosed by CMR served as control(HCM group). Outpatient and in-hospital clinical data as well as follow up results were compared. The major adverse cardiovascular events were defined as malignant arrhythmia events (including sudden cardiac death, ventricular flutter/ventricular fibrillation) and heart failure events (including heart transplantation, progressive heart failure). Results: Compared with HCM group, patients in HCM-LVAA group had a more positive family history of HCM(P=0.04), higher incidence of ST-T segment changes and abnormal Q wave in electrocardiograms (both P<0.01), the CMR derived left ventricular end-diastolic transverse diameter and end-diastolic volume index were also significantly higher (both P<0.05), and delayed enhancement was more significant ((25.26±10.60)% vs. (15.78±7.33)%, t=3.12, P=0.004) in HCM-LVAA group. Moreover, the left ventricular ejection fraction ((54.4±10.6)% vs. (67.5±7.6)%, t=-4.28, P<0.000 1) and the thickness of the apical wall ((3.11±1.05) mm vs. (5.46±1.94) mm, t=-4.49, P<0.000 1) were significantly lower in HCM-LVAA group than in HCM group. The mean follow-up duration was (3.46±1.64) years, 4 patients in HCM-LVAA group (22.2%) developed 4 cardiovascular events, including 1 sudden cardiac death, 3 progressive heart failures. One patient in HCM group developed progressive heart failure. Conclusion The prognosis of the HCM complicating with LVAA patients is worse than that of HCM patients without LVAA, and the amount of late gadolinium enhancement is higher than that of HCM patients without LVAA.

Objective: To evaluate the clinical and cardiac magnetic resonance (CMR) features of apical hypertrophic cardiomyopathy (ApHCM) patients complicating with left ventricular apical aneurysm (LVAA). Methods: CMR confirmed 25 ApHCM patients complicating with LVAA from January 2010 to December 2017 in Fuwai hospital were included in this study, and the baseline clinical data and CMR characteristics were retrospectively analyzed. There were 14 pure ApHCM (hypertrophy limited at the apical segments) complicating with LVAA patients and 11 mixed ApHCM (predominantly apical hypertrophy along with thickening of contiguous non-apical left ventricular region) with LVAA patients. Results: In this patient cohort,age of 84% (21/25) patients ranged between 20-70 years old, and 68% (17/25) were male. There were 68% (17/25) patients with complaint of chest distress symptom, 56% (14/25) with complaint of chest pain, 32% (8/25) with complaint of palpitation,16% (4/25) with complaint of dyspnea, and 12% (3/25) presented as syncope. ST-T segment changes of electrocardiogram were observed in all patients, and giant negative T waves were detected in 80% patients (20/25). The rate of missed diagnosis by echocardiography for detecting ApHCM and LVAA was 16% (4/25) and 68% (17/25), respectively. CMR showed discrete thin-walled dyskinetic or akinetic segment of the most distal portion of the left ventricular chamber in ApHCM patients with LVAA. Transmural late gadolinium enhancement of the aneurysmal rim was detected in 76% (19/25) patients, and the maximum transverse dimension of aneurysm was bigger in patients with transmural late gadolinium enhancement than in patients without transmural late gadolinium enhancement ((22.0±10.8)mm vs. (11.7±4.0) mm, P=0.033). Conclusion ApHCM with LVAA patients have distinct cardiac clinical features, and CMR is the most useful tool for the accurate and objective evaluation of this disease.

OBJECTIVE: Segmented cardiac cine magnetic resonance imaging (MRI) is the gold standard for cardiac ventricular volumetric assessment. In patients with difficulty in breath-holding or arrhythmia, this technique may generate images with inadequate quality for diagnosis. Real-time cardiac cine MRI has been developed to address this limitation. We aimed to assess the performance of retrospective electrocardiography-gated real-time cine MRI at 3T for left ventricular (LV) volume and mass measurement. MATERIALS AND METHODS: Fifty-one patients were consecutively enrolled. A series of short-axis cine images covering the entire left ventricle using both segmented and real-time balanced steady-state free precession cardiac cine MRI were obtained. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), and LV mass were measured. The agreement and correlation of the parameters were assessed. Additionally, image quality was evaluated using European CMR Registry (Euro-CMR) score and structure visibility rating. RESULTS: In patients without difficulty in breath-holding or arrhythmia, no significant difference was found in Euro-CMR score between the two techniques (0.3 ± 0.7 vs. 0.3 ± 0.5, p > 0.05). Good agreements and correlations were found between the techniques for measuring EDV, ESV, EF, SV, and LV mass. In patients with difficulty in breath-holding or arrhythmia, segmented cine MRI had a significant higher Euro-CMR score (2.3 ± 1.2 vs. 0.4 ± 0.5, p < 0.001). CONCLUSION: Real-time cine MRI at 3T allowed the assessment of LV volume with high accuracy and showed a significantly better image quality compared to that of segmented cine MRI in patients with difficulty in breath-holding and arrhythmia.
Arrhythmias, Cardiac ; Diagnosis ; Heart Ventricles ; Humans ; Magnetic Resonance Imaging ; Magnetic Resonance Imaging, Cine* ; Retrospective Studies* ; Stroke Volume

The paper presented the implementation of the healthcare reform policy and initial success of Xinyu TCM Hospital in its reform pilot work of public hospital reform in Xinyu city ,Jiangxi province. The authors also analyzed problems and causes of the hospital in business development and cost control during the reform ,proposing to carry out TCM development policy ,enhance government investment ,streamline TCM service pricing ,and innovate TCM supporting model. In addition ,they also proposed TCM hospitals to enhance management ,and reform their mechanism to resolve such problems as high operating costs ,and poor talent development and lack of feature disciplines .

OBJECTIVETo evaluate the clinical effects on incomplete intestinal obstruction treated with the adjuvant therapy of acupuncture and moxibustion.

METHODSUsing the retrospective analysis, 80 patients of incomplete intestinal obstruction were divided into an observation group and a control group, 40 cases in each one. In the control group, the routine treatment was given, such as fasting, gastrointestinal decompression, parenteral nutrition, infection prevention with antibiotics and enema laxative. In the observation group, on the basis of the treatment as the control group, acupuncture was applied at bilateral Zusanli (ST 36), Shangjuxu (ST 37) and Xiajuxu (ST 39); moxibustion was used at left Yangchi (TE 4), Zhongwan (CV 12), Qihai (CV 6) and Guanyuan (CV 4). The treatment was given once a day, 30 min each time. The average days of treatment, the surgical transfer rate, the time to first flatus, the recovery time of defecation and the time of solid food intake were observed in the patients of the two groups.

RESULTSThe average days of treatment in the observation group was obviously less than that in the control group (<0.05). The surgical transfer rate in the observation group was obviously lower than that in the control group (<0.05). The time to first flatus, the recovery time of defecation and the time of solid food intake were all obviously earlier than those in the control group (all <0.05).

CONCLUSIONThe adjuvant therapy of acupuncture and moxibustion achieves the significant therapeutic effects on incomplete intestinal obstruction, shortens the treatment duration and reduces the surgical transfer rate and the patient's economic burden.

Objective To investigate the characteristics of clinical and cardiovascular magnetic resonance imaging(CMR) of arrhythmogenic cardiomyopathy with left ventricular(ALVC) involvement. Methods Ten cases of arrhythmogenic cardiomyopathy with left ventricular involvement and sixteen randomly chosen cases of arrhythmogenic cardiomyopathy with right ventricular (ARVC) involvement were enrolled in this study. Clinical symptoms, cardiac electrophysiological changes as well as the cardiac morpharage, ventricular functions and delayed enhancement of myocardium assessed by CMR were compared between the two groups. The size of heart chambers, global ventricular functions and the fat/fibrosis infiltration were evaluated by turbo fast spin echo, ture FISP cine and delayed enhancement. These were statistically analyzed by independent samples t test, respectively.Results There was no significant difference in age and gender between two groups. All the patients in two groups presented non-specific clinical manifestations with no significant differences (P>0.05) except for short of breath(P=0.034). The end-diastolic diameter of left ventricular, left ventricular end-diastolic volume index, left and right ejection fraction in ALVC and ARVC group were (64.2±7.7), (49.2±5.9) mm(t=5.551,P<0.001), (113.9±24.0), (69.2± 30.0) ml/m2(t=3.962, P<0.001), (38.5±3.1)%, (56.0±8.4)%(t=-6.733,P<0.001), (42.0±5.5)%, (18.0±7.3)%(t=8.817, P<0.001) respectively. An medium of 11 and 14 segments of fat or fat/fibrosis were found in intramural wall of the LV myocardiumin patients with ALVC,while only 0 segment(all P<0.001)was found in patients with ARVC.Conclusions The clinical manifestations of arrhythmogenic cardiomyopathy with left ventricular involvement was similar to ARVC, however, with regarding to cardiac morphological, functional and myocardial lesions, these two diseases have different characteristics in CMR features.“one-stop-shop”MRI examination has high value in the diagnosis of arrhythmogenic cardiomyopathy with Left ventricular involvement.