Objective　 : To analyze the monitoring data of 131I internal exposure in Guangdong Province over the past 3years, study the thyroid 131I contamination levels among nuclear medicine staff, and provide a basis for optimizing themonit-oring plan. Methods　 : Using a convenience sampling method, 574 detections of nuclear medicine staff from 28 hospitals inGuangdong Province were included in the study. The thyroid 131I activity was measured directly in vivo. Differences indetec-tion rates were analyzed, and committed effective doses were estimated. Results　 : Over the past 3 years in GuangdongProvince, 131I accumulation was found in the thyroids of staff from 14 hospitals for 62 (10.8%) detections, with an averageactivity of 154.8 (13.2-8730.6) Bq. The adjusted annual intake was 50.7 (4.5-820.6) kBq. The committed effective dose was0.56 (0.05-9.03) mSv/a, and the values were ≥ 2 mSv for 8 persons. Among different positions, nurses showed the highestdetection rate (19.6%), followed by cleaners (14.7%), with significant differences (P<0.05). Among different exposure types,the detection rate was highest for loading medication into automatic dispenser (23.3%), and the mean activity was highest forentering thyroid cancer patient ward (495.4 Bq), with significant differences (P<0.05). Conclusion　 Monitoring of 131Iin-ternal exposure in Guangdong Province found that the radiation doses of some staff members had exceeded the thresholdspecified in other investigations. Routine personal 131I internal exposure monitoring should be conducted, with increasedmonitoring frequency. Priority should be given to nurses and cleaners, with monitoring extended to cleaners and outsourceddispensing staff.

Objectives: Vertebral fractures are associated with disability and mortality, but most vertebral fractures are asymptomatic. The present study aimed to determine the incidence of and develop a predictive nomogram for asymptomatic vertebral fractures in Vietnamese adults. Methods: This cohort study as a part of the Vietnam Osteoporosis Study involved 168 men and 287 women aged 50 years and older without a clinically diagnosed vertebral fracture. Their spine x-rays were taken at the recruitment and subsequent 2-year visit. Vertebral fractures were ascertained using the Genant’s semiquantitative method. We employed the Bayesian Model Averaging method to search for the optimal model for predicting asymptomatic vertebral fractures. A predictive nomogram was also developed to facilitate risk prediction. Results: During a median of 2.38 years of follow-up, 13 men and 16 women developed an asymptomatic vertebral fracture, yielding the overall incidence rate of 28 fractures per 1000 person-years, or 33 fractures/1000 personyears in men and 24 fractures/1000 person-years in women, respectively. Most asymptomatic vertebral fractures were moderate, almost 1.5 times more common than mild fractures. The optimal model for predicting incident asymptomatic vertebral fractures included age, male sex and lower femoral neck T-score. The area under the receiver’s operating characteristic curve was 0.91, with 95% CI ranging from 0.86 to 0.96. Conclusions Asymptomatic vertebral fractures were relatively common among adults in Vietnam. A simple model with sex, age and femoral neck T-score is helpful for selective screening of asymptomatic vertebral fractures in Vietnamese individuals.

Objective:To explore the independent risk factors for uremic encephalopathy(UE)in maintenance hemodialysis(MHD)patients and provide evidence for early clinical warning and intervention.Methods:A case-control study was conducted,enrolling 67 MHD patients diagnosed with UE(UE group)at Laibin People's Hospital from January 2010 to December 2024,and 67 non-UE patients during the same period(control group).Demographic characteristics,dialysis parameters,laboratory indicators,and infection events were collected.Univariate and multivariate logistic regression analyses were used to identify independent risk factors for UE.Results:The UE group had significantly higher rates of infection(58.2％vs.29.9％),serum creatinine(789 vs.702 μmol/L),and iPTH levels(568 vs.385 pg/mL)compared to the control group(P＜0.05).Multivariate analysis revealed that concurrent infection(OR=3.022,95％CI:1.312-6.958),elevated serum creatinine(OR=1.004,95％CI:1.000-1.008),and elevated iPTH(OR=1.002,95％CI:1.001-1.003)were independent risk factors for UE(P＜0.05).The combined prediction model achieved an AUC of 0.878(95％CI:0.822-0.934),with 82.1％sensitivity and 80.6％specificity.Conclusion:Infection,elevated serum creatinine,and elevated iPTH significantly increase the risk of UE in MHD patients.Clinical management should emphasize infection prevention,toxin clearance optimization,and parathyroid function regulation to reduce UE incidence.

To formulate an expert consensus on the principles of preoperative hair removal and provide scientific guidance for standardized removal of hair before surgical procedures so as to reduce the incidence of surgical site infections.METHODS Led by the Hospital Management Institute of National Health Commission of the People's Republic of China,this consensus was reached with the joint efforts from the expects of relevant fields such as surgeries,interventional therapies,nursing,and infection prevention and control.The consensus facilitates the classification and evaluation of literatures by following the evidence grade formulated by Oxford Evidence-based Medicine Center and focuses on the association of preoperative hair removal with surgical site infection,it reaches the evidence grade of expert consensus and recommendation intensity by integrating with discussions on meetings and clinical experience of the expects from relevant fields.RESULTS A total of 6 items of consensus were reached by summarizing the latest evidence on the aspects including the indications for preoperative hair removal,tools,range,timing and places.CONCLUSION The consensus,to some extent,make supplements to and complete the exiting regulations and standards.It provides guidance for the medical institutions to carry out the preoperative hair removal.

Objective To carry out cervical cancer VMAT radiotherapy planning respectively with the single-criteria optimization(SCO)and multi-criteria optimization(MCO)modes of Raystation 4.7 planning system,and to provide references for selecting optimization mode clinically by comparing and analyzing the dosimetric parameters such as target dose distribution,exposure dose to organ at risk(OAR),monitor unit and beam-on time.Methods Ten cervical cancer patients who attended some hospital from February to December 2022 were retrospectively selected,and some VMAT plans were designed for them with the SCO mode of Raystation 4.7 planning system and then enrolled into a SCO group;other VMAT plans were redesigned with the MCO mode under the premise the setup conditions such as machine model and shot field angle were unchanged,and divided into a MCO group.The two groups were compared in terms of maximum dose(D2%),minimum dose(D98%),homogeneity index(HI)and conformity index(CI)of the planning target volume(PTV),beam-on time,monitor unit and exposure doses to OARs including bladder V50 Gy,V40 Gy and V30 Gy,rectum V50 Gy,V40 Gy and V30 Gy,small intestine V50 Gy,V40 Gy and V30 Gy and left and right femur V50 Gy,V40 Gy and V30 Gy.SPSS 22.0 software was used for statistical analysis.Results Both the two groups met clinical requirements.There were no significant differences between the two groups in D98%,CI,small intestine V50 Gy and left and right femur V40 Gy(P>0.05).The MCO group had the values of HI,D2%,V50 Gy,V40 Gy and V30 Gy,rectum V50 Gy,V40 Gy and V30 Gy,small intestine V40 Gy and V30 Gy and left and right femur V30 Gy lower than those of the SCO group,with the differences being statistically significant(P<0.05).The SCO group had less monitor units and shorter beam-on time when compared with the MCO group,with the differences being statistically siginificant(P<0.05).Conclusion When compared with the SCO mode-based VMAT plans,the MCO mode-based VMAT plans significantly decrease the exposure doses and volume to rectum,bladder and small intestine and raise the PTV homogeneity,while lower the treatment efficiency to some extent by increased monitor units and prolonged beam-on time.[Chinese Medical Equipment Journal,2025,46(9):39-44]

Objective:To investigate the influence of the complexity metrics of the multi-leaf collimator (MLC) on the γ-pass rate of volumetric modulated arc therapy (VMAT) plans for nasopharyngeal carcinoma (NPC).Methods:A total of 60 VMAT plans for NPC were selected to measure the γ-pass rate. The MLC data across all control points (CPs) in each VMAT plan were analyzed to calculate the mean field area (MFA), average leaf gap (ALG), small aperture score (SAS), and their corresponding weighted metrics including MFAW, ALGW, and SASW, considering dose weight (W). Pearson′s bivariate correlation analysis was conducted to examine the correlations between MLC complexity metrics and the γ-pass rate. Moreover, the receiver operating characteristic (ROC) analysis was employed to assess the predictive efficacy of MLC complexity metrics on dose verification result.Results:Under the 3%/3 mm, 3%/2 mm, and 2%/2 mm criteria, the MFA in the 60 VMAT plans exhibited a positive correlation with the γ-pass rate ( r=0.82, 0.79, 0.72, P<0.05), and the MFAW was also positively correlated with the γ-pass rate ( r=0.83, 0.81, 0.75, P<0.05). The ALG manifested a positive correlation with the γ-pass rate ( r=0.82, 0.79, 0.74, P<0.05), as did the ALGW ( r=0.83, 0.81, 0.77, P<0.05). The SAS(0-1 cm), SAS(1-2 cm), SAS(2-3 cm), and SAS(3-4 cm) displayed negative correlations with the γ-pass rate ( r= -0.86, -0.82, -0.71, -0.84, -0.82, -0.72, -0.79, -0.79, -0.73, -0.30, -0.35, -0.42, P<0.05), whereas the SAS(4-5 cm), SAS(5-6 cm), and SAS(6-40 cm) showed positive correlations with the γ-pass rate ( r=0.49, 0.45, 0.33, 0.73, 0.71, 0.59, 0.79, 0.79, 0.76, P<0.05). The outcomes of SASW reveal slightly stronger correlations than those of SAS. In terms of correlations among complexity metrics, a positive correlation was observed between MFA and ALG ( r=0.98, P<0.05). ALG was negatively correlated with SAS(0-1 cm), SAS(1-2 cm), SAS(2-3 cm), and SAS(3-4 cm) ( r= -0.95, -0.94, -0.89, -0.39, P<0.05), and positively correlated with SAS(4-5 cm), SAS(5-6 cm), and SAS(6-40 cm) ( r=0.51, 0.77, 0.92, P<0.05). The weighted result mirrored these correlations. The ROC-derived analytical result indicate that MFA, MFAW, ALG, ALGW, SAS(0-1 cm), SAS(1-2 cm), SAS(2-3 cm), SAS(6-40 cm), SASW(0-1 cm), SASW(1-2 cm), SASW(2-3 cm), and SASW(6-40 cm) demonstrated exceptional predictive efficacy for dose verification result [Area under the curve (AUC) > 0.9, P<0.05]. Conclusions:The γ-pass rate of VMAT plans for NPC is strongly correlated with MLC complexity metrics, which demonstrate excellent predictive efficacy for dose verification result. The increased uncertainty in dose calculations and measurements caused by narrow fields generated by the MLC is a significant factor contributing to the reduced γ-pass rate of VMAT plans. This finding is associated with discrepancies in the precision of treatment planning system (TPS) modeling and the accuracy of dose verification tools, providing a reference for similar challenges.

Objective:To investigate the differences in dosimetric parameters for target volumes and organs at risk (OARs), radiation doses to reconstructed tissues, and beam-on time in radiotherapy among helical tomotherapy (HT), volumetric modulated arc therapy (VMAT), and fixed-field intensity-modulated radiotherapy (F_IMRT) following immediate breast reconstruction for breast cancer, thereby providing a reference for the selection of clinical radiotherapy techniques.Methods:This study retrospectively investigated 15 breast cancer patients who underwent radiotherapy following modified radical mastectomy and immediate breast reconstruction at the Liuzhou Worker′s Hospital from August 2018 to July 2023. During target volume delineation, precautions were taken to avoid the reconstructed tissues, which were delineated separately. Customized HT, VMAT, and F_IMRT treatment plans were designed for each patient. The plans were categorized into the HT, VMAT, and F_IMRT groups based on different radiotherapy techniques employed. They were comparatively analyzed through one-way analysis of variance (ANOVA), with multiple comparisons further conducted in the case of significant differences.Results:Statistical analyses reveal significant differences in various parameters of target volumes among the three groups of plans ( F = 38.73, 14.95, 37.01, 48.05, 35.55, 22.56, 34.30, P < 0.05). Pairwise comparisons indicate that the maximum dose ( D2%), minimum dose ( D98%), mean dose ( Dmean), and the proportion of high-dose volumes within the target volume ( V107%and V110%) in both the HT and VMAT groups were significantly better than those in the F_IMRT group. The HT group demonstrated the optimal conformity index (CI), while the VMAT group displayed the superior homogeneity index (HI) compared to the other two groups. In terms of OAR, the V20 of the ipsilateral lung was the lowest in the HT group ( F = 14.31, P < 0.05) and the highest in the F_IMRT group ( F = 14.31, P < 0.05). However, the V5 and Dmean for both the ipsilateral and contralateral lungs in the HT group significantly surpassed those of the other groups ( F = 39.16, 31.91, P < 0.05). The mean dose Dmean ( F = 5.57, P < 0.05) of the contralateral breast was significantly reduced in the VMAT group compared to the other two groups. No statistically significant differences were observed for other OARs, including the heart, spinal cord PRV, thyroid, and humeral head ( P > 0.05). The radiation doses to reconstructed tissues ( Dmax, V53.5, Dmean) ascended in the order of HT, VMAT, and F_IMRT groups ( F = 17.69, 17.53, 15.11, P < 0.05). The HT and F_IMRT groups showed similar beam-on times ( P > 0.05), both exceeding that of the VMAT group by several folds ( F = 28.72, P < 0.05). Conclusions:The comparative analysis indicates that the three radiotherapy techniques exhibit distinct advantages and limitations, with F_IMRT demonstrating the least comprehensive advantage. HT can enhance the conformity of target volumes while reducing the overall radiation doses to reconstructed tissues and the crucial indicator V20 in the ipsilateral lung. VMAT demonstrates the highest treatment efficiency, yielding improved dose uniformity in the target volume and reduced radiation doses to the contralateral breast. It is advisable to prioritize HT or VMAT based on actual clinical conditions.

Objective:To investigate the molecular characteristics of low-risk acute myeloid leukemia(AML)at recurrence,and analyze the factors affecting retreatment efficacy and prognosis.Methods:A retrospective analysis was conducted on the clinical and laboratory data of 31 patients with newly diagnosed low-risk AML who relapsed during consolidation treatment or follow-up after treatment in our hospital from April 2017 to January 2023.Gene mutations before and after relapse were compared,retreatment efficacy following relapse was evaluated,and univariate and multivariate analyses were performed to identify factors influencing treatment efficacy and prognosis.Results:Gene sequencing results after relapse showed that the most common newly acquired mutation was FLT3-ITD,while RAS mutation detected at initial diagnosis were predisposed to loss of expression during relapse.The median overall survival(OS)after relapse for the entire cohort was 349(170-528)days,with non-hematopoietic stem cell transplantation(HSCT)group and HSCT group demonstrating median survival times of 210(106-314)days and not reached,respectively(P=0.001).Multivariate analysis revealed that age ≥60 years was a significant risk factor for achieving remission after retreatment in initially diagnosed low-risk AML patients who experienced relapse(OR=18.222,95％CI:1.188-279.597,P=0.037).Additionally,DNMT3A mutation was identified as an independent risk factor for OS(HR=13.165,95％CI:2.018-85.877,P=0.007),while HSCT post-relapse demonstrated significant survival benefits(HR=0.133,95％CI:0.025-0.698,P=0.017)and served as an independent protective factor for OS.Conclusion:Relapsed low-risk AML is often associated with loss of RAS and novel mutations in FLT3-ITD.Age ≥ 60 years and DNMT3A mutations were identified as independent adverse factors for achieving subsequent remission and post-relapse survival,respectively,while HSCT significantly improved patient outcomes.

Background and Aims:Secondary hyperparathyroidism(SHPT)is a common and difficult-to-treat complication of chronic kidney disease(CKD),significantly impairing patients'quality of life and prognosis.For patients who respond poorly to medical therapy,surgical intervention remains an effective treatment option.This study aimed to evaluate the clinical efficacy and safety of total parathyroidectomy with forearm autotransplantation(tPTX+AT)in the treatment of CKD-related SHPT.Methods:A retrospective analysis was conducted on 40 patients with CKD complicated by SHPT who underwent tPTX+AT in Gaozhou People's Hospital between January 2020 and June 2023.Changes in intact parathyroid hormone(iPTH),serum phosphorus,calcium,alkaline phosphatase(ALP),and bone mineral density(BMD)were recorded preoperatively and at multiple postoperative time points.Postoperative symptom relief,complications,and follow-up outcomes were also analyzed.Results:A total of 158 parathyroid glands were removed during surgery.Among the patients,38 had four glands successfully excised,while two had only three glands removed.After operation,levels of iPTH,phosphorus,calcium,and ALP decreased significantly compared to preoperative values(all P<0.05),and BMD increased significantly at 3 months(P<0.05).Symptoms such as bone pain,pruritus,and restless leg syndrome improved markedly by 3 months postoperatively(all P<0.05).Hypocalcemia occurred in 34 cases(85.0%);one patient experienced transient recurrent laryngeal nerve injury and one had superior laryngeal nerve injury,both of which resolved after treatment.The two patients who had only three glands removed exhibited persistent SHPT postoperatively,with iPTH levels of 457 pg/mL and 609 pg/mL,respectively.Although their symptoms improved partially,the condition was medically controlled without the need for reoperation.Conclusion:tPTX+AT can effectively correct mineral metabolism disorders and improve BMD and clinical symptoms in SHPT patients.The procedure achieves a high rate of complete gland resection and stable autograft function.Although postoperative hypocalcemia is common,overall complications are manageable.This surgical approach is safe and effective for the treatment of refractory SHPT.

Objective To investigate the status of hearing impaired children's hearing device independence skills,and to explore the ways to improve their self-use of hearing equipment.Methods This study surveyed 64 re-habilitation teachers and 411 parents of children with hearing impairment aged 0-12 years.Through face-to-face or remote telephone interview,3 good habits(A asking parents for advice before removing the HA,B putting the de-vice into a moisture-proof box after removing it,C bringing batteries to school and knowing where are them)and 3 key abilities[D wearing the device independently,E replacing the battery independently,and F independently handle foreign bodies in the ear mold(Fa)and water vapor(Fb)]was investigated.The age when mastering skills or de-veloping habits difference of hearing impaired children in different groups were compared.Results ① The ratio of ability D in the bilateral CI group and the bilateral HA group of preschool children was 30.97％and 18.57％respec-tively.Among elementary school children,85.29％and 90.70％had this ability respectively.② The ratio of ability E in the bilateral CI group,the bilateral HA group and the bimodel group were 11.50％,15.71％and 16.49％,re-spectively.Among elementary school children,64.71％,53.49％and 68.52％had this ability,respectively.③Among preschool children,there was no statistical difference in age when different equipment groups developed the three good habits and acquired ability D and E(P＞0.05).④ Among primary school children,there was a statisti-cal difference in the age when different equipment groups formed habit A(P＜0.05),and the age when double CI group had this ability was slightly earlier than the double HA group.There was no significant difference in other abilities among age groups(P＞0.05).Conclusion The age at which hearing impaired children develop the three good habits precedes the age at which they master the key skills,which accords with the law of skill acquisition and development of ordinary children.Corresponding teaching process should be based on the age and ability of hearing-impaired children without considering the type of equipment.