Study of dose distortion and Bragg peak location correction in MRI-guided proton therapy / 中华放射肿瘤学杂志

Objective:To analyze the influence of magnetic field on the proton beam delivery and dose distribution, and develop a correction method for the Bragg peak (BP) shift under the vertical magnetic field, providing reference for the dose calculation and beam delivery of MRI-guided proton therapy.Methods:Monte Carlo (MC) simulation was used to study the dose distribution of the proton beam in the water phantom under the magnetic field. The BP location was corrected by the method of" angle correction+ energy correction" , and the correction parameters were calculated by the analytical formula based on the simulation data.Results:The magnetic field caused the dose distortion and shift of BP location. The shift degree was increased with the increase of field strength and initial energy. Compared with MC simulation, the result of calculating proton deflection in the air by the analytical method yielded a deviation within 0.2%. Based on the simulation data and calculation formulas, the correction parameters under different conditions could be calculated within 1 s by using the MATLAB programming. The calculation results showed that the air layer with magnetic field, isocenter depth, irradiation direction exerted different influence on the correction parameters. After correction, the BP location was basically consistent with the expected (offset ≤0.2 mm).Conclusions:The BP shift under the vertical magnetic field can be effectively corrected by " the angle correction+ energy correction" method. The correction parameters under different conditions can be quickly and accurately calculated by the calculation formulas based on simulation data.

The development and verification of an independent dose calculation toolkit for proton Therapy / 中华放射肿瘤学杂志

Objective:To develop and validate the accuracy of an independent dose calculation toolkit for the horizontal beamline of Shanghai Advanced Proton Therapy (SAPT) facility based on an open-source dose calculation engine.Methods:Machine data, such as absolute integral depth doses (IDDs) and lateral profiles in air were measured and lateral profiles in water were derived by Monte-Carlo simulations. The dose computation models for SAPT horizontal beamline pencil beams in water were achieved by combining machine data and dose calculation engine. The verification of the dose reconstruction toolkit included absolute dose verification and relative dose verification. The absolute dose verification is performed to mainly compare the reconstructed value and the measured value at different depths along the center axis of the beam direction of a cube plan. The relative dose verification is conducted to mainly compare the lateral profile or two-dimensional dose distribution between the measured value and the reconstructed value. Meanwhile, the precision of double-gaussian and single-gaussian lateral beam models was compared.Results:The deviations of the absolute dose between the calculated and measured values were basically within 2%. The deviations of 20%-80% penumbra between the measured and the calculated values were within 1 mm, and deviations of the full width at half height were within 2 mm. For 3 cube plans and 2 clinical cases, the two-dimensional gamma pass rates (3 mm/3%) between the measured and calculated dose distributions at the corresponding depths were greater than 95%. The double-gaussian lateral beam model was more accurate in the high dose gradient region and deeper depth.Conclusion:The precision of independent dose calculation toolkit is acceptable for clinical requirements, which can be employed to investigate other dose-related issues.

Planning target volume-Is it still suitable for intensity modulated proton therapy for lung cancer? / 中华放射肿瘤学杂志

Objective:To demonstrate the concept of planning target volume (PTV) is not suitable for intensity proton therapy (IMPT) in lung cancer, plan differences were compared based on the concept of PTV and Internal target volume (ITV), aiming to provide clinical reference.Methods:Six patients were retrospectively selected and approved by the local ethics committee. Each of the six patients received two IMPT plans based on a synchronous accelerator model, developed by SINAP team (Shanghai Institute of Applied Physics, China Academy Science University) and commercial treatment system: one with the PTV-based robust IMPT (PTV-IMPT) plan and the other with ITV-based robust IMPT (ITV-IMPT) plan. Three beams were set in all plans, and the final dose was calculated using Monte Carlo dose algorithm. The plan quality and robustness of PTV-IMPT and ITV-IMPT plans were evaluated quantitatively.Results:Compared to the PTV-IMPT plan, ITV-IMPT plan showed better target conformity index (conformability index: 0.58 vs.0.43), better homogeneity index (homogeneity index: 0.96 vs.0.92), lower V 5Gy in normal lung tissue (13.1% vs.13.5%) and maximum dose in spinal cord (8.9 Gy vs. 9.5 Gy) as well as plan monitor unit (MU: 338 vs. 401) . In addition, ITV-IMPT plan showed more robust in target coverage (0.003-0.032 vs. 0.02-0.28), and normal lung tissue was also found a bit robust in the ITV-IMPT plan ( 0.06-0.11, 0.07-0.13). Conclusions:Compared with the PTV-IMPT plan, ITV-IMPT plan has the advantages of high planning quality, well robustness and better tumor motion mitigation. Therefore, ITV concept is recommended to be applied in the IMPT plan for lung cancer.

Correlation analysis between Dx-pH monitoring and proton pump inhibitor test in the diagnosis of laryngopharyngeal reflux disease / 中华耳鼻咽喉头颈外科杂志

Objective@#The consistency of 24-hour oropharyngeal Dx-pH monitoring and proton pump inhibitor(PPI) test in the diagnosis of laryngopharyngeal reflux disease (LPRD) was investigated.@*Methods@#Sixty patients with laryngopharyngeal reflux (LPR) related symptoms who had never received PPI treatment were assessed by reflux symptom index (RSI) and reflux finding score (RFS) between October 2017 and October 2018, including 28 males and 38 females, aged from 16 to 72 years, with a medium age of 38 years. Prior to treatment, all patients were evaluated with 24 hours oropharyngeal Dx-pH monitoring(Restech). After empiric therapy with PPI twice-daily for 8 weeks, the efficacy was evaluated according to posttreatment RSI score.The data was analysed with Kruskal-Wallis test, Student Newman Keuls test and consistency check.@*Results@#(1)Among all 60 patients,13 patients (21.7%) had pathologic Ryan score and all resulted responsive to PPI;27 patients (45.0%) with a negative Ryan score were unresponsive to PPI; 20 patients (33.3%) despite a negative Ryan score resulted responsive to PPI therapy. Considering responsiveness to PPI therapy as the gold standard for the diagnosis of LPRD, the sensitivity, specificity, positive predictive value and negative predictive value of Ryan score were 39.4%, 100%, 100% and 57.4% respectively. The Kappa value was 0.369 (P<0.01). (2)Among 34 patients (56.7%) with positive Dx-pH results (24-hour oropharyngeal acid reflux events≥ 3 times), 29 patients were positive and 5 patients were negative in PPI test. Among 26 patients with negative Dx-pH results (24-hour oropharyngeal acid reflux events<3 times), 4 patients were positive and 22 patients were negative in PPI test. Considering responsiveness to PPI therapy as the gold standard for the diagnosis of LPRD, the sensitivity, specificity, positive predictive value and negative predictive value of 24-hour oropharyngeal acid reflux events were 87.9%, 81.5%, 85.3% and 84.6% respectively. The Kappa value was 0.696(P<0.01).@*Conclusions@#There is a positive correlation between 24-hour oropharyngeal Dx-pH monitoring positive results (24-hour oropharyngeal acid reflux events≥3 times) and PPI test in the diagnosis of LPRD. The 24-hour oropharyngeal Dx-pH monitoring can be a promising tool for the diagnosis of suspected LPRD patients, and more sensitive and accurate Dx-pH diagnostic index will be required in the clinic.

Expression and clinical significance of CK4, CK13 in sinonasal squamous cell carcinoma / 中国耳鼻咽喉头颈外科

[ABSTRACT]OBJECTIVETo investigate the expression of cytokeratin (CK) 4 and 13 in sinonasal squamous cell carcinoma (SNSCC) and their pathobiological implications for tumor angiogenesis and metastasis. METHODSThe expression of CK4 and CK13 was detected by immunohistochemistry in normal and cancerous tissues in 42 cases of SNSCC, integral optical density (A) was measured by computer analysis of images and analyzed by SPSS13.0.RESULTSCK4 and CK13 were expressed significantly higher in normal tissues than in cancerous tissues of SNSCC. Moreover, the expression level of CK4 and CK13 was related to the differentiation of SNSCC, which was higher in the well/middle differentiated ones than in poor ones. The expression of CK4 was significantly associated with the tumor size, clinical stage and cervical lymphatic metastasis in SNSCC. While CK13 had no relationship with these three factors.CONCLUSIONThe detection of CK-4 and CK-13 might play an important role in the prognostic evaluation of SNSCC.

Onset time and efficacy of sublingual immunotherapy with Dermatophagoides farinae drops in children with allergic rhinitis / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To investigate the onset time and efficacy of sublingual immunotherapy (SLIT) with Dermatophagoides farinae drops in children with house dust mites (HDM)-induced allergic rhinitis (AR).</p><p><b>METHODS</b>One hundred and forty three children with perennial moderate to severe HDM-induced AR were treated by SLIT with standardized Dermatophagoides farinae extract. One hundred children who finally completed two years treatment were divided into two groups according to the age: younger children group (aged 4-8 years, n = 52) and older children group (aged 9-14 years, n = 48). Respectively, Each children was assessed before and after 1st, 2nd, 3rd, 6th, 12th, 24th months of the treatment. Total nasal symptom score (TNSS), total medication score (TMS) and visual analogue scale (VAS) were evaluated at each visit. All clinical data were analyzed retrospectively with the SPSS 19.0 software.</p><p><b>RESULTS</b>TNSS, TMS and VAS of two groups decreased significantly after three months of the treatment compared with before (younger children group: Z value was -3.843, -3.534, -3.940, older children group: Z value was -3.938, -3.405, -3.953, all P < 0.05). TNSS and VAS of younger children group decreased significantly after two months of the treatment compared with before (6.4 ± 1.6, 5.3 ± 1.4 vs 8.6 ± 1.2, 7.9 ± 1.6, Z value was -3.843, -3.940, both P < 0.05). Five children (5%) experienced local adverse events and 2 children (2%) experienced mild systemic adverse events. No severe adverse events happened during the treatment.</p><p><b>CONCLUSIONS</b>SLIT with Dermatophagoides farinae drops is an efficient and safe treatment for children with HDM-induced AR. Its onset of action can be observed as early as 3 months after treatment.</p>

Clinical characteristics of benign paroxysmal positional vertigo secondary to sudden deafness / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To retrospectively analyze the clinical characteristics of the benign paroxysmal positional vertigo (BPPV) secondary to the sudden deafness (SD) and to explore pathogenetic mechanism.@*METHOD@#One hundred and seventy-eight cases of the SD in our department were retrospectively analyzed. They were all treated under the guidance of clinical guidelines.@*RESULT@#(1) In all these patient's with SD, there were 31 cases with BPPV secondary to the SD. There were 26 cases of BPPV of posterior semicircular canal and 5 cases of BPPV of lateral BPPV semicircular canal. All patients with BPPV were diagnosed as the same ears as the SD, including 16 cases on left sides and 15 on right sides. (2) The interval between the onset of SD and BPPV was less than one week in 27 cases, between one week and one month in 3 cases, and between one and three months in 1 case. (3) All patients with BPPV secondary to the SD were cured with Epley maneuver or Barbecue roll maneuver.@*CONCLUSION@#The occurrence of BPPV may follow SD, and the major of BPPV secondary to the SD occurs in the posterior semicircular canal. The canalith repositioning is an effective therapy to the secondary BPPV.

Investigations on nutritional status and nutritional risk in hospitalized pediatric patients / 临床儿科杂志

Objectives To validate the Screening Tool for the Assessment of Malnutrition in Pediatrics (STAMP) in hospitalized pediatric patients, and to assess the nutritional status and nutritional risk using STAMP. Methods the nutritional status of hospitalized pediatric patients was investigated by adopting STAMP. The STAMP score≥4 was deifned as a high standard of nutritional risk. Results Among 1 506 hospitalized children, children with high nutritional risk accounted for 26.56%. The overall prevalence of malnutrition and stunting was 19.12%and 10.16%, respectively. There was signiifcant diffe-rence in stunting among each department (P<0.05), which was the highest in department of internal pediatrics. The proportion of patients receiving nutritional support was 10.09%. Among them, the rate of parenteral and enteral nutrition support was 7.84%and 2.92%, respectively. The ratio of parenteral nutrition to enteral nutrition was 2.68:1. After intervention to hospitalized pa-tients with high nutritional risk, the overall prevalence of high nutritional risk decreased from 26.56%at admission to 21.71%at discharge (P<0.05). Conclusions STAMP can objectively relfect the possible malnutritional risk in hospitalized pediatric patients. The nutrition condition of the pediatric patients can be improved through nutritional risk management.

Sustaining Quality Improvement Used in Preventing Perineum Wound Infection / 中华医院感染学杂志

OBJECTIVE To discuss the function of sustaining quality improvement in preventing perineum wound infection.METHODS The perineum wound infection situation in 2003 was retrospectively analyzed,and since then the measures for sustaining quality improvement were implemented.RESULTS In 2004 and in 2005 the perineum wound infection percentage and the stitch inflammation rate were obviously reduced than in 2003.The difference was statisticaly significant.CONCLUSIONS Sustaining quality improvement is an unceasing,gradually advancing and long-term process.The prevention of perineum wound infection is a long time work for obstetrics workers.To carry out strictly the aseptic technical operation,grasp skilled suture technology,choose easily absorbable suture,maintain suitable cleanliness and nursing and use the antibiotic could be effectively to prevent the perineum wound infection and the stitch inflammation occurrence.

Relationship and Significance Among HPV16/18 Infection and Expression of Telomerase Reverse Transcriptase,c-myc Protein in Laryngeal Squamous Cell Carcinomas / 医学研究杂志

Objective To investigate the relationship among human papillomavirus(HPV)16/18 and the expression of human telomerase reverese transcriptase(hTERT),c-myc protein in laryngeal squamous cell carcinomas and their significance.Methods The infection of HPV16/18 in 39 laryngeal carcinoma specimens and 10 vocal cord polyp specimens were detected by in situ hybridization.The expression of hTERT protein and c-myc protein in 39 laryngeal carcinoma specimens and 10 vocal cord polyp specimens were detected by immunohistochemistry.Results The positive rate of HPV16/18 infection in 39 laryngeal carcinoma specimens was 48.7%(19/39).The positive rate of HPV16/18 expression in 10 vocal cord polyps was 0(0/10).Statistical tests showed that HPV 16/18 infection was significantly higher in LSCC than that in vocal cord polyps.The positive rate of hTERT protein and c-myc protein expression in 39 laryngeal carcinoma specimens was 84.6%(33/39)and 82.1%(32/39)respectively.The positive rate of hTERT protein and c-myc protein expression in 10 vocal cord polyps was 0(0/10)and 10%(1/10)respectively.Statistical tests showed that hTERT and c-myc protein expression was significantly higher in LSCC than that in vocal cord polyps.Spearman rank correlation analysis revealed that there was significant relation among HPV16/18,hTERT and c-myc protein respectively.Conclusions The results suggest that the expression of hTERT and c-myc protein was associated significantly with the infection of HPV16/18 and they intact each other,which can influent the pathogenesis of laryngeal squamous cell carcinomas.

Human Papillomavirus16/18 Subgroup Infection in Laryngeal Squamous Cell Carcinomas / 医学研究杂志

Objective To investigate the correlation between human papillomavirus(HPV) 16/18 subgroup infection and laryngeal squamous cell carcinoma(LSCC).Methods The infection of HPV16/18 in 39 laryngeal carcinoma specimens and 10 vocal cord polyp specimens were detected by in situ hybridization. Results The positive rate of HPV16/18 expression in 39 laryngeal carcinoma specimens was 48.7%(19/39). The positive rate of HPV16/18 subgroup expression in 10 vocal cord polyps was 0(0/10) . Statistical test showed that HPV16/18 subgroup infection was significantly higher in LSCC than that in vocal cord polyps. No statistically association was observed among the frequency of HPV16/18 subgroup infection and TNM stages, degree of differentiation or lymph nodes metastases. Conclusions HPV 16/18 subgroup infection is associated with he pathogenesis of LSCC.