Objective To investigate the effect of different strand lengths of 125I seeds with the same activity on the dose of different reference points around the seeds.Methods The scanned images were transferred to the three-dimensional treatment planning system(3D-TPS)according to DICOM format.The target volume was delineated at 5 mm and 10 mm above and below the center of the phantom,and a 0.8 mCi seeds strand was simulated.The 1-20 seeds were arranged with an equal spacing of 5 mm(5 mm-100 mm).The 5 mm points above and below the center of the seeds strand were defined as point A and point A',and the 10 mm points above and below the center were defined as point B and point B'.5 mm above and below the edge of the seeds strand on the left side were defined as AL points and AL'points,and 5 mm above and below the edge of the seeds strand on the right side were defined as AR points and AR'points.Similarly,points 10 mm above the above mentioned positions were defined as BL points,BL'points,BR points,BR'points.The average dose symmetry points were measured at AL,AL',AR,and 5 mm,10 mm,15 mm and 20 mm inside AR' of the 45 mm-100 mm seeds strand.The dose at the center was compared with the dose at the end points.The dose at the center point A was compared with the average dose at the symmetry points of 5 mm,10 mm,15 mm and 20 mm inside of the end points AL,AL',AR and AR',and the dose at each point was curve fitting.The correlation between each point and seeds strands of different lengths was analyzed.Results There was a positive correlation between the dose and the length of each point.There was no statistically significant difference between the center point and the end point.There was a statistically significant difference in dosage at points 5 mm and 10 mm inside from point A,while there was no statistically significant difference in dosage at points 15 mm and 20 mm inside from point A.The dose of A,A',B and B' point increased steadily with the increase of seed chain length,and the fitting curves were obtained respectively:y=e(-0.620/x+5.28)(R2=0.992),y=e(-0.640/x+5.34)(R2=0.987),y=e(-0.82/x+4.80)(R2=0.984),y=e(-0.82/x+4.83)(R2=0.9g1).Conclusion The doses at points A,A',B,and B'are positively correlated with seeds strand length and have a high degree of stability.Point A can be used as a reference point for the target area dose of the seeds strand,and point B can be used as a reference point for the dose to critical organs.The dose at other positions is more variable and thus has a certain degree of uncertainty as a reference point for the seeds strand dose.

Objective To investigate the relationship between the absorbed dose and implantation duration at the target area and at the critical organ dose reference points in the application of radioactive 125I seed strands for the treatment of intraluminal tumors.Methods A self-developed 125I seed strand arc template with a 30-degree angle was used to place 10 seeds(each with activity of 1.0mCi)into the template.CT-based DICOM images were transferred to a treatment planning system(TPS)for dose calculation.Absorbed doses at multiple time points(from day 5 to day 90 with a 5-day interval)were measured at following four specific locations:point A'(5 mm inside the arc center),point A(5 mm outside the arc center),point B(10 mm outside the arc center),and point B'(10 mm inside the arc center).The TPS was first used to calculate the expected absorbed doses,followed by actual absorbed dose measurements over the 90-day period.The expected absorbed doses were calculated,and then the actual absorbed doses were calculated.The time-dose relationship of the above points was analyzed,and the curves and equations were obtained.Results The expected absorbed doses at points A',A,B,and B'were 221.36,196.39,115.78,and 136.32 Gy,respectively.The time(x)-dose(y)relationships of all the above points followed a quadratic function relationship in the form of y=c+bx-ax2.Within the time range of 5-90 days,the actual absorbed dose increased with the prolongation of time,and the increase speed showed a pattern of first fast and then slow.The increase in speed was fast within 20 days,than became stable between 20-75 days,and after 75 days the increase in speed became to slow down.Conclusion When using 125I seed strands to treat intraluminal tumors,the actual absorbed dose of the tumor needs to be accurately calculated based on the implantation duration.The actual absorbed dose initially accumulates rapidly and decreases significantly after 75 days.It is recommended to replace the 125I seed strand with a new one after implanting it for approximately 75 days.

Objective To investigate the impact of different 125I seeds strand radian on the dose of different reference points around the seeds.Methods CT scan of self-developed radioactive particle radiation dose measurement phantom was performed,the scanned images were transferred to the three-dimensional treatment planning system(TPS).The target area at the middle level of the model was drawn.The target volume was delineated at 5 mm and 10 mm above and below the center of the phantom.125I seeds strand plans were designed with different radians,with a total length of 8 cm,seed spacing of 0 cm,activity of 0.8 mCi,and a total of 16 particles,with radians ranging from 30°to 170°,increasing by 10° increment.The point 5 mm vertically away from the center of the seeds strand towards the center was named A',and the point away from the center was named A.The point 10 mm vertically away from the center of the seeds strand towards the center was named B',and the point away from the center was named B.The doses at different radians were recorded,and the actual absorbed dose at 1-2 months after operation was calculated based on the particle activity decay formula.Results The doses at points A'and A were(218.3±23.1)and(201.5±16.0)Gy respectively(P=0.001).The actual absorbed doses at 1 month after operation were(65.5±6.9)and(60.5±4.8)Gy respectively(P=0.001),and the actual absorbed doses at 2 months after operation were(109.2±11.5)Gy and(100±7.9)Gy respectively(P=0.001).The doses at points B'and B were(95.9±11.0)Gy and(81.7±4.9)Gy respectively(P＜0.001),and the actual absorbed doses at 1 month after operation were(28.8±3.3)Gy and(24.5±1.5)Gy respectively(P＜0.001).The actual absorbed doses at 2 month after operation were(48.0±5.5)Gy and(41.0±2.4)Gy respectively(P＜0.001).The doses at points A'and A gradually decreased with the increase of the radians,reaching the minimum value at 100 degrees,and then increased gradually,showing a cubic function change.The actual absorbed dose showed the same trend.The doses at points B'and B increased gradually with the increase of the radians,showing a cubic function change.Conclusion At different radians,the point doses and absorbed doses on the centrifugal side of the seeds strand are both less than those on the centripetal side.There is a cubic function relationship between the dose at the reference points and the radian of the seeds strand.

Objective:To investigate the incidence of radiation pneumonitis (RP) induced by 125I seed implantation for the treatment of malignant lung tumors and analyze related dosimetric parameters. Methods:A retrospective analysis was conducted on 31 cases of malignant lung tumors treated with 125I seed implantation from January 2017 to December 2022 at Hebei Provincial Tumor Radioactive Seeds Implantation Diagnosis and Treatment Center. These cases consisted of eight patients with squamous cell carcinoma, 10 patients with adenocarcinoma, and 13 patients with metastatic cancer in other sites. At 1-6 months after treatment, these patients received postoperative chest CT scans, with the efficacy evaluated based on the Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1), including the objective response rate (ORR) and the disease control rate (DCR). The efficacy of RP was evaluated using the Radiation Therapy Oncology Group (RTOG) criteria. Postoperative dosimetric parameters, including D90 (minimum peripheral dose received by 90% of the target volume), V8 (percentage of lung volume receiving 8 Gy), V32 (percentage of lung volume receiving 32 Gy), and Dmean (mean radiation dose) of the affected lung, were statistically analyzed. The relationships of the RP occurrence with postoperative D90, V8, V32, and Dmean were analyzed by comparison with relevant external radiotherapy data, to identify the parameters that are correlated closely with RP occurrence. Results:All the patients underwent successful surgeries. The postoperative efficacy evaluation after six months showed complete response (CR) in 11 cases, partial response (PR) in 11 cases, stable disease (SD) in eight cases, and progressive disease (PD) in one case, with an overall response rate (ORR) of 71.0%, and a disease control rate (DCR) of 96.8%. Three patients suffered RP, with an incidence rate of 9.7%. Postoperative V8, V32, and Dmean could not serve as predictive indicators for RP. Follow-up observation revealed that three RP cases (3/5) exhibited postoperative D90 exceeding 170 Gy and no RP cases (0/26) showed postoperative D90 below 170 Gy. Conclusions:In the treatment of malignant lung tumors with 125I seed implantation, there is a certain correlation between RP and postoperative D90, while there is no correlation between it and V8, V32, and Dmean.

Objective:To explore the clinical efficacy of 125I seeds implantation in treating cancer-induced pain and motor dysfunction caused by brachial plexus compression through neurophysiological monitoring. Methods:A retrospective study was conducted on 8 patients (4 males, 4 females; age 58-63 years) who underwent 125I seeds therapy for cancer-induced brachial plexus injury at Hebei Provincial People′s Hospital from January 2021 to August 2023. Pain severity was assessed by using the numerical rating scale (NRS) and motor function was evaluated by using the Fugl-Meyer (F-M) assessment. Electrophysiological monitoring was used to assess changes in sensory and motor branch conduction velocity (CV) of the musculocutaneous nerve, axillary nerve, median nerve, ulnar nerve, and radial nerve before and 3 months after treatment. Paired t-test was used for data analysis. Results:All 8 patients had moderate to severe pain (6 had motor dysfunction). The preoperative and postoperative NRS scores was 5.9±1.0 and 3.3±1.7, respectively ( t=4.93, P=0.002), while F-M scores was 44.8±7.6 and 54.8±5.7, respectively ( t=-3.52, P=0.017). Electrophysiological results showed that 7 patients had lesion involvement in the lower trunk of the brachial plexus, and 1 patient had involvement in the upper trunk. The preoperative and postoperative motor branch CV of the ulnar nerve was (47.2±2.6) and (59.7±8.2) m/s, respectively ( t=-3.17, P=0.034), while the sensory branch CV was (41.8±1.2) and (56.0±5.7) m/s, respectively ( t=-5.82, P=0.001). The nerve CV increased compared to the preoperative ones. Conclusions:125I seeds implantation has good clinical efficacy in treating cancer-related pain and motor dysfunction caused by brachial plexus compression. Changes in electrophysiology can quantitatively monitor the recovery of sensory and motor functions of the brachial plexus.

Objective:To understand the negative experiences of male master of nursing students during their studies.Methods:In this qualitative study, totally 11 male master of nursing students from China Medical University and Wuhan University were selected by purposive sampling in March 2023 for semi-structured interviews, and the data were analyzed using the KJ method.Results:Four themes were extracted: research pressure, pressure of time and finances, confusion about the future and development, and lack of identification with the nursing profession.Conclusions:Male master of nursing students experience negative emotions during their studies. Nursing educators and administrators should pay attention to the emotional management of male master of nursing students and gradually improve the training methods for nursing graduate students.

Objective:To explore the influence of chronic rhinitis on depressive symptoms of college freshmen and the mediating effect of avoidant personality.Methods:A cluster sampling method was used to survey 8 079 college freshmen from April 2018 to October 2018 using the Beck depression inventory and the avoidant personality diagnosis questionnaire based on DSM-Ⅳ.SPSS 25.0 software was used for descriptive statistics and Spearman correlation analysis, and the macro program PROCESS version 3.3 was used for the mediating effect.Results:(1) The detection rates of chronic rhinitis, avoidant personality and depressive symptoms were 22.90% (1 850/8 079), 19.22% (1 553/8 079) and 6.28% (507/8 079). The scores for avoidant personality disorder and depressive symptoms were 1.00 (0, 3.00) and 1.00 (0, 4.00), respectively. (2) The chronic rhinitis, avoidant personality and depressive symptoms were positively correlated ( rchronic rhinitis-avoidant personality=0.094, rchronic rhinitis-depressive symptoms=0.095, ravoidant personality-depressive symptoms=0.416, all P<0.001). (3) Chronic rhinitis could positively predict depressive symptoms ( β=1.113, P<0.001). (4) Avoidant personality played a mediating role between chronic rhinitis and depressive symptoms ( β=1.094, P<0.001), and accounted for 44.92%(0.500/1.113) of the total effect. Conclusion:Chronic rhinitis directly affect the depressive symptoms of college freshmen, and indirectly affect the depressive symptoms of college freshmen through the mediating role of avoidant personality.

Objective:To analyze the influencing factors of short-term efficacy of 125I seed implantation for recurrent cervical metastatic lymph nodes of esophageal squamous cell carcinoma after external beam radiation therapy (RESCC). Methods:From January 2013 to March 2019, 47 patients (42 males, 5 females; age: 47-77 years) with RESCC who underwent CT guided 125I seed implantation in Hebei General Hospital were retrospectively analyzed. Patients were divided into effective group (complete remission (CR)+ partial remission (PR)) and ineffective group (stable disease (SD)+ progressive disease (PD)) according to response evaluation criteria in solid tumors (RECIST) at 3 months after implantation. Multivariate logistic regression was used to analyze the independent influencing factors of short-term efficacy. Cut-off values were determined by ROC curve. Results:Of 47 patients, 26 were effective (3 were CR and 23 were PR) and 21 were ineffective (7 were SD, 14 were PD). Multivariate regression analysis showed that tumor diameter, immediate postoperative dose delivered to 90% gross tumor volume ( D90), recurrence interval time were independent influencing factors of short-term efficacy (odds ratio ( OR; 95% CI): 4.240(1.220-14.737), 0.999(0.999-1.000), 0.989(0.979-1.000), Wald values: 5.163, 5.043, 3.956, all P<0.05). ROC curve showed that the AUC of tumor diameter, D90 and recurrence interval time were 0.782, 0.786 and 0.838 respectively, with cut-off values of 4.85 cm, 115.78 Gy and 297.5 d respectively. Conclusions:The short-term efficacy of 125I seed implantation for RESCC is mainly related to the tumor diameter, immediate postoperative D90 and recurrence interval time. Patients with tumor diameter <4.85 cm, immediate postoperative D90>115.78 Gy and recurrence interval time >297.5 d have better efficacy.

Objective:To investigate the relationship between dosimetric parameters and tumor volume change after 125I implantation for thyroid cancer and obtain better dosimetric parameters that predict the curative effect more accurately. Methods:A total of 22 consecutive patients with thyroid cancer (23 targets) who received 125I interstitial brachytherapy in Department of Oncology, Hebei General Hospital were retrospectively analyzed. All the patients received post-operative dose verification, and the D 90 (Minimum dose received by 90% target volume) was calculated. After a regular follow-up, the tumor volume reduction ratio after t months (R t) , actual absorbed dose (D 1m) , efficacy corrected absorbed dose (D 1e) , and sensitivity corrected absorbed dose (D 1s) of the first month were calculated according to the actual follow-up CT images. The statistical test was carried out by SPSS21.0. The Spearman linear analysis was applied to analyze the relationship between D 90, D 1m, D 1e, D 1s and R t, and the curve fitting was also completed. Results:The post-operative D 90, D 1m, D 1e, D 1s and R t were (129.73±14.22) Gy, (36.95±7.35) Gy, (43.45±11.32) Gy, (41.78±13.39) Gy, and (32.00±19.00) %, respectively. And the correlation coefficient were 0.692, 0.551, 0.728, and 0.858, respectively, which showed significant positive relevance between dosimetric parameters and tumor volume change ( P<0.01) , the curve fitting presented cubic function. Conclusion:The post-operative D 90, D 1m, D 1e, and D 1s can be predictors for curative effect, and D 1s is the best predictor.

Objective: To analyze the factors influencing the short-term efficacy of CT-guided ¹²⁵I seeds implantation in the treatment of recurrent and metastatic tumors in head and neck. Methods: A total of 73 patients (61 males, 12 females; age: (59.1±11.5) years) with head and neck tumors recurrence and metastasis treated by ¹²⁵I seeds implantation in Hebei General Hospital from January 2015 to April 2019 were retrospectively enrolled. The implanted seeds activity was 11.1-29.6 MBq, and the prescription dose was 80.0-145.0 Gy. CT examination was conducted 3 months after ¹²⁵I seeds implantation. According to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, short-term efficacy was classified as effective (complete remission (CR), partial remission (PR)) and ineffective (stable disease (SD), progressive disease (PD)). Univariate analysis of factors affecting short-term effect (gender, age, history of radiation therapy, Karnofsky performance status (KPS) scores, pathological type, the longest diameter of tumor, implantation patterns, seeds activity, immediate postoperative dose delivered to 90% gross tumor volume (D₉₀), and with adjuvant chemotherapy post-surgery or not) were conducted. Variables with P<0.2 were enrolled in logistic multivariate regression analysis. In addition, artificial neural network (ANN) was constructed with all influencing factors as independent variables and short-term efficacy as dependent variables. Finally, receiver operating characteristic (ROC) curve analysis was performed for the common influencing factors in logistic regression analysis and ANN analysis. Results: There were 34 with effective results and 39 with ineffective results. Logistic regression analysis indicated that the longest diameter of tumor, immediate postoperative D₉₀, with adjuvant chemotherapy post-surgery or not had significant impacts on the short-term efficacy (Wald values: 6.950, 4.804, 4.790, all P<0.05); According to results of ANN analysis, the top 5 in order of importance for short-term efficacy prediction were immediate postoperative D₉₀, the longest diameter of tumor, age, seeds activity and gender. ROC curve analysis indicated that the longest diameter of tumor and immediate postoperative D₉₀ were the best predictors for short-term efficacy, with the threshold of 5.25 cm and 110.05 Gy respectively, and the area under the curve (AUC) was 0.843 and 0.847 respectively (both P<0.001). Conclusions The short-term efficacy of ¹²⁵I seeds implantation in the recurrence and metastasis of head and neck tumors is mainly related to the longest diameter of tumor and immediate postoperative D₉₀. Patients with the longest diameter of tumor <5.25 cm and with D₉₀>110.05 Gy can achieve better efficacy.