Neuron-derived extracellular vesicles promote neurogenesis of neural stem cells / 中国组织工程研究

BACKGROUND:It has been shown that neural stem cells can differentiate into neurons,astrocytes,and oligodendrocytes.Mesenchymal stem cells-derived extracellular vesicles have also been shown to cross the blood-brain barrier to reach sites of central nervous injury and promote neural repair.However,it is not clear whether neuron-derived extracellular vesicles promote the differentiation of neural stem cells in a direction that is beneficial for neurogenesis. OBJECTIVE:To investigate whether neuron-derived extracellular vesicles facilitate neural stem cell differentiation towards neurogenesis. METHODS:Neurons and neural stem cells were extracted from neonatal SD rat cerebral cortex by trypsin digestion.Cell supernatants of neurons were collected.Neuron-derived extracellular vesicles were extracted.Neural stem cells cultured for 10 days were co-cultured with neuron-derived extracellular vesicles or PBS for 7 days.Immunoblotting,immunofluorescence,and RT-qPCR were used to detect proteins specifically expressed by neurons,neural stem cells,oligodendrocytes,and astrocytes. RESULTS AND CONCLUSION:The neural stem cells co-cultured with neuron-derived extracellular vesicles showed high expression of neuron-specific proteins and oligodendrocyte-specific proteins including β3-tubulin,neurofilament 200 and myelin basic protein,and low expression of astrocyte-specific protein glial fibrillary acidic protein.These results suggest that neuron-derived extracellular vesicles can promote the differentiation of neural stem cells into neurons and oligodendrocytes and prevent the differentiation of neural stem cells into astrocytes.

Progress in clinical application of 125I seeds brachytherapy in the treatment of oral and maxillofacial malignant tumors / 中华核医学与分子影像杂志

Oral and maxillofacial malignant tumors threaten the life and health of patients, and seriously affect their swallowing, language function and face. 125I seeds brachytherapy for oral and maxillofacial malignant tumors has been widely concerned and studied because of its advantages such as less surgical trauma, large and uniform dose distribution in the target tissue, little damage to the surrounding normal tissue, and reducing radiation exposure of medical staff. Low-dose brachytherapy with 125I seeds can effectively reduce the tumor volume and prolong the survival time of patients. This article reviews the clinical application of 125I seeds brachytherapy in oral and maxillofacial malignant tumors.

3D-PCT-assisted CT-guided radioactive particle implantation precision / 中华放射医学与防护杂志

Objective:To study the precision of 3D printing coplanar template (3D-PCT) assisted CT-guided radioactive particle implantation using two types of phantoms, and compare the differences between the phantoms, in order to provide reference for radioactive particle implantation.Methods:The needle inserting path was designed in the brachytherapy treatment planning system (BTPS) and the needle tip coordinates were obtained. Following the needle inserting path, the implant needles were inserted into the custom and the liver phantoms, respectively. Then gold markers were implanted through the needles. Subsequently, the needles were withdrawn by 10 mm, and the cold sources were implanted. The coordinates of needle tips, gold markers, and cold sources were recorded. The precision of implanted needles, first particles, and particles after needle withdrawal were obtained by calculating the distance between two points in the space. Finally, the differences between the two phantoms were compared through independent samples t-test. Results:In the 3D-PCT-assisted CT-guided radioactive particle implantation, the precision of implanted needles, first particles, and particles after needle withdrawal in the custom and the liver phantoms was (1.89±0.72) and (2.14±0.88 ) mm ( P>0.05), (2.03±1.14) and (2.42±1.12) mm ( P>0.05), and (-1.96±1.29) and (-2.82±0.91) mm ( t=2.09, P=0.046), respectively. Conclusions:The 3D-PCT-assisted CT-guided radioactive particle implantation is efficient, stable, and precise, showing slight precision differences between the two phantoms.

Thinking about academic exchange promoting the training of young talents in public hospitals / 现代医院

Academic exchange is an important part of cultivating young talents,which plays an important role in promo-ting knowledge dissemination,broadening academic horizons,cultivating scientific research thinking,improving innovation abili-ty,strengthening peer review,and conducting interdisciplinary cooperation.Based on the connotation and significance of academ-ic exchange,this paper analyzes the main problems faced by public hospitals in the process of academic exchange,and puts for-ward some promotion strategies,such as strengthening institutional guarantees,increasing funding support,increasing publicity efforts,and standardizing process management,creates a good academic exchange atmosphere,constructs a diverse academic ex-change platform,and provides reference for improving the quality of young talent cultivation in public hospitals.

Biejiajian Wan Regulates Polarization of Macrophages via HIF-1α/NF-κB Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of Biejiajian Wan on liver fibrosis by regulating the polarization of macrophages. MethodRaw264.7 cells were cultured in vitro by serum pharmacological method， and the hypoxia model of RAW264.7 cells was established by stimulating RAW264.7 cells with cobalt chloride （CoCl2）. The cells were randomly divided into blank group， CoCl2 hypoxia model group （200 mmol·L-1）， Biejiajian Wan low-dose group （200 mmol·L-1+0.55 g·kg-1 Fuzheng Quyu capsules）， medium-dose group （200 mmol·L-1+1.1 g·kg-1 Biejiajian Wan）， and high-dose group （200 mmol·L-1+2.2 g·kg-1 Biejiajian Wan） and Fuzheng Quyu capsule group （200 mmol·L-1+0.56 g·kg-1 Biejiajian Wan）. Cell proliferation was detected by cell counting kit-8 （CCK-8）， and the gene expression of hypoxia inducible factor-1α （HIF-1α）， interleukin-1β （IL-1β） and interleukin-6 （IL-6） in macrophages was detected by real time fluorescence quantitative polymerase chain reaction （Real-time PCR）. The expression of macrophage polarization-related protein and HIF-1α/nuclear factor-kappa B （NF-κB） signaling pathway-related protein was tested by Western blot， and the distribution and expression of NF-κB signaling pathway-related protein and HIF-1α were determined by cell immunofluorescence. ResultCompared with the conditions in the blank group， the proliferation of RAW264.7 cells was inhibited after CoCl2 stimulation for 24 hours （P<0.05）， the mRNA expression of HIF-1α， IL-1β and IL-6 in the model group were increased （P<0.05）， the protein expression of HIF-1α and M1 macrophage phenotypic proteins IL-6 and tumor necrosis factor-α （TNF-α） was boosted while that of M2 macrophage phenotypic protein interleukin-10 （IL-10） was reduced （P<0.05）， the protein expression of NF-κB p65， phosphorylation （p）-NF-κB p65， phosphorylated NF-κB inhibits protein kinase α/β （p-IKKα/β） and phosphorylated NF-κB inhibits protein α (p-IκBα） was elevated （P<0.05）， the nuclear expression of HIF-1α and NF-κB p65 was promoted. Compared with the conditions in the model group， after 24 hours of treatment with corresponding drug-containing serum， each treatment group promoted the proliferation of RAW264.7 cells （P<0.05）， the mRNA expression levels of HIF-1α， IL-1β and IL-6 in macrophages were reduced （P<0.05）， the protein expression of HIF-1α， IL-6 and TNF-α was decreased， while that of CD163 and IL-10 was increased （P<0.05）， the protein expression of NF-κB p65， p-NF-κB p65， p-IKKα/β and p-IκBα was lowered （P<0.05）， the nuclear expression of HIF-1α and NF-κB p65 was inhibited. ConclusionBiejiajian Wan could modulate the polarization of macrophages， attenuate the injury of macrophage-associated inflammatory response under hypoxia， and thus delay the progression of liver fibrosis， which might be related to its regulation of HIF-1α/NF-κB signaling pathway.

Biejiajian Wan Regulates Polarization of Macrophages via HIF-1α/NF-κB Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of Biejiajian Wan on liver fibrosis by regulating the polarization of macrophages. MethodRaw264.7 cells were cultured in vitro by serum pharmacological method， and the hypoxia model of RAW264.7 cells was established by stimulating RAW264.7 cells with cobalt chloride （CoCl2）. The cells were randomly divided into blank group， CoCl2 hypoxia model group （200 mmol·L-1）， Biejiajian Wan low-dose group （200 mmol·L-1+0.55 g·kg-1 Fuzheng Quyu capsules）， medium-dose group （200 mmol·L-1+1.1 g·kg-1 Biejiajian Wan）， and high-dose group （200 mmol·L-1+2.2 g·kg-1 Biejiajian Wan） and Fuzheng Quyu capsule group （200 mmol·L-1+0.56 g·kg-1 Biejiajian Wan）. Cell proliferation was detected by cell counting kit-8 （CCK-8）， and the gene expression of hypoxia inducible factor-1α （HIF-1α）， interleukin-1β （IL-1β） and interleukin-6 （IL-6） in macrophages was detected by real time fluorescence quantitative polymerase chain reaction （Real-time PCR）. The expression of macrophage polarization-related protein and HIF-1α/nuclear factor-kappa B （NF-κB） signaling pathway-related protein was tested by Western blot， and the distribution and expression of NF-κB signaling pathway-related protein and HIF-1α were determined by cell immunofluorescence. ResultCompared with the conditions in the blank group， the proliferation of RAW264.7 cells was inhibited after CoCl2 stimulation for 24 hours （P<0.05）， the mRNA expression of HIF-1α， IL-1β and IL-6 in the model group were increased （P<0.05）， the protein expression of HIF-1α and M1 macrophage phenotypic proteins IL-6 and tumor necrosis factor-α （TNF-α） was boosted while that of M2 macrophage phenotypic protein interleukin-10 （IL-10） was reduced （P<0.05）， the protein expression of NF-κB p65， phosphorylation （p）-NF-κB p65， phosphorylated NF-κB inhibits protein kinase α/β （p-IKKα/β） and phosphorylated NF-κB inhibits protein α (p-IκBα） was elevated （P<0.05）， the nuclear expression of HIF-1α and NF-κB p65 was promoted. Compared with the conditions in the model group， after 24 hours of treatment with corresponding drug-containing serum， each treatment group promoted the proliferation of RAW264.7 cells （P<0.05）， the mRNA expression levels of HIF-1α， IL-1β and IL-6 in macrophages were reduced （P<0.05）， the protein expression of HIF-1α， IL-6 and TNF-α was decreased， while that of CD163 and IL-10 was increased （P<0.05）， the protein expression of NF-κB p65， p-NF-κB p65， p-IKKα/β and p-IκBα was lowered （P<0.05）， the nuclear expression of HIF-1α and NF-κB p65 was inhibited. ConclusionBiejiajian Wan could modulate the polarization of macrophages， attenuate the injury of macrophage-associated inflammatory response under hypoxia， and thus delay the progression of liver fibrosis， which might be related to its regulation of HIF-1α/NF-κB signaling pathway.

Recent advance in circulating micro RNAs as biomarkers in intracranial aneurysm / 中华神经医学杂志

Micro RNAs in body fluids, enjoying convenient collection and less invasion, have the potential of being biomarkers of intracranial aneurysm (IA), and are suitable for early screening and rupture prediction of IA. The stable micro-RNAs (circulating micro RNAs) in serum, plasma and other body fluids are involved in regulating the functions of vascular smooth muscle cells and endothelial cells, and play important roles in pathophysiological process of IA progression. In this paper, the current research progress of circulating micro RNAs as biomarkers in the early diagnosis, rupture prediction and prognoses of IA are summarized as follows.

Recognition of cancer-neuroscience and its role in glioma research / 中华神经医学杂志

With the development of oncology and neuroscience, cancer-neuroscience, as their interdisciplinary subject, has also attracted widespread scholars' attention in recent years. People have gradually realized that neurons are involved in the formation of tumor microenvironment and affect the initiation and progression of tumor. Similarly, tumor can also cause nervous system remodeling and dysfunction. The relationship between glioma, as the most common malignant tumor in the central nervous system, and neurons have gained a new understanding. This review discusses the latest advance in cancer-neuroscience in the study of gliomas, and systematically reviews the mechanism of interaction between neurons and glioma cells.

Dosimetric evaluation of 125I seed implantation assisted by an optical navigation system and a 3D-printing template in the treatment of recurrent head and neck cancers / 中华放射医学与防护杂志

Objective:To verify the accuracy and feasibility of radioactive 125I seed implantation assisted by an optical navigation system and a 3D-printing non-coplanar template in the treatment of recurrent head and neck cancers. Methods:A total of 12 patients with recurrent head and neck cancer treated with radioactive 125I seed implantation assisted by an optical navigation system and 3D-printing non-coplanar template were enrolled from Dec 2018 to Dec 2019.The pre-plan and post-implant implantation needle number and implanted seed number were recorded.Meanwhile, their dosimetric parameters were compared, including D90, minimum peripheral dose (MPD), V100, V150, V200, conformity index (CI), external index (EI), and the homogeneity index (HI) of the target volume. Results:The median lesion volume was 31.5 cm 3, the median number of seeds was 61.5, and the median prescription dose was 130 Gy.The means of the pre-plan D90, MPD, V100, V150 and V200 were 134.2, 64.6, 93.3, 75.3 and 39.3 Gy, respectively, while those of post-implant D90, MPD, V100, V150, and V200 were 146.7, 68.94, 97.47, 80.40 and 48.30 Gy, respectively, with no statistically significant difference ( P>0.05). Meanwhile, there was no statistically significant difference between the pre-plan and post-implantation needle number, implanted seed number, CI, HI, and EI ( P>0.05). In terms of postoperative dose quality assessment, eight cases were rated excellent (66.6%) and four cases were rated good (33.3%). Conclusions:Radioactive 125I seed implantation assisted by an optical navigation system and 3D-printing non-coplanar template can be accurately performed in the treatment of recurrent head and neck cancer, with good consistency between pre-plan and post-implant dosimetric parameters and thus of prospective potential in clinical application.

Preoperative dosimetric comparison between non-coplanar and coplanar template-assisted 125I seed implantation for pancreatic cancers / 中华放射医学与防护杂志

Objective:To compare preoperative planning parameters between non-coplanar and coplanar template-assisted radioactive seed implantation in the treatment of pancreatic cancers, in order to guide clinical application.Methods:Patients with pancreatic cancers who received external irradiation in the Peking University Third Hospital from Jan 2017 to May 2019 were selected.Their image information was imported into the brachytherapy planning system, and the non-coplanar plan and coplanar plan were designed individually.Each patient′s prescription dose was set to 110 Gy, and the activity of the radioactive seeds were 0.4 mCi(1 Ci=3.7×10 10Bq), respectively.For the two plans, the dose distribution was optimized and dosimetric parameters were compared, including the implantation needle number, the implanted seed number, the minimum prescription doses delivered to 90% and 100% of the target volume ( D90 and D100), mean percentages of volume receiving 100%, 150% and 200% of the prescription doses ( V100, V150 and V200), conformity index (CI), external index (EI), and homogeneity index (HI) of the target volume, as well as the doses of 2 cm 3 and 5 cm 3 ( D2 cm 3 and D5 cm 3) of the surrounding normal organs such as the small intestines, colon, duodenum, stomach, and spinal cord. Results:The implantation needle number in the coplanar plan was slightly higher than that in the non-coplanar plan, namely 18.63 vs. 16.45 ( t=-3.239, P <0.05). The implanted seed number was equivalent, namely 90.2 vs. 91.01, with no statistical difference ( P>0.05). There was no significant difference between D90, D100, V100, V150, V200, CI, EI, and HI in the target area of the two plans ( P>0.05). Meanwhile, there was no obvious difference in D2 cm 3 and D5 cm 3 of normal organs including the small intestines, colon, duodenum, stomach, and spinal cord ( P>0.05). Conclusions:With both the coplanar plan and the non-coplanar plan, the prescription doses can be achieved and meanwhile, there are very small differences in the doses of normal organs.Given that 3D-printing non-coplanar and coplanar templates have their own characteristics, it is necessary to choose them according to specific situations.

Dosimetry evaluation of navigation system-assisted and CT-guided seed implantation in the treatment of recurrent malignant pelvic tumors / 中华放射医学与防护杂志

Objective:To explore the accuracy of CT-guided 125I seed implantation assisted by a navigation system and 3D-printing template in the treatment of recurrent malignant pelvic tumors by comparing pre-plan and intraoperative physical dosimetric parameters. Methods:This study involved 15 patients with recurrent malignant pelvic tumors who received CT-guided radioactive 125I seed implantation assisted by a navigation system and 3D-printing template in the Peking University Third Hospital from Dec 2018 to Feb 2020.Seven of the patients had cervical cancers, seven had rectal cancers, and one had prostate cancer.The median age was 55 years (34-84 years old). The prescription dose was 100-150 Gy.The pre-plan and post-implant data were compared, including the number of implanted seeds, implantation needle number, and some dosimetric parameters such as the minimum prescription doses delivered to 90% and 100% of target volume( D90, D100), mean percentages of volume receiving 100%, 150%, and 200% of the prescription doses( V100, V150, and V200), conformity index(CI), external index(EI), and homogeneity index(HI)of the target volume. Results:The median lesion volume was 29.20 cm 3, the median seed number was 54, and the median D90 was 150 Gy.The post-implant V150 was lower than pre-plan V150 (64.1% vs. 67.1%, t=2.937, P=0.011), and the post-implant mean HI was higher than pre-plan HI (32.01% vs. 26.68%, t=-2.950, P=0.011). There were no significant differences in other dosimetric parameters before and after seed implantation. Conclusions:With CT-guided radioactive seed implantation assisted by a navigation system and 3D-printing template in the treatment of recurrent malignant pelvic tumors, the actual postoperative dose could meet the preoperative plan requirement, ensuring the accuracy and consistency of the dose delivered.

Feasibility of 3D-printing template-assisted and CT-guided 192Ir interstitial brachytherapy in the treatment of recurrent gynecologic tumors / 中华放射医学与防护杂志

Objective:To investigate the accuracy and feasibility of 3D-printing individualized template-guided and CT-guided 192Ir interstitial brachytherapy in the central recurrent gynecologic tumors by comparing pre-plan and intraoperative physical dosimetric parameters. Methods:This study involved 38 patients with central recurrent gynecologic tumors who underwent 3D printing individual template (3D-PIT)-assisted and CT-guided 192Ir interstitial brachytherapy in the Department of Radiation Oncology of the Peking University Third Hospital from Jan 2018 to Dec 2019.The prescription doses for the target tumor areas were 10-36 Gy to be delivered at 5-6 Gy/fraction for 2-6 fractions.The pre-plan and intraoperative dosimetric parameters were compared, including the minimum prescription doses delivered to 90% and 100% of target volume( D90, D100)and the mean percentage of volume receiving 100% of the prescription doses ( V100). Meanwhile, the doses delivered to 2 cm 3 ( D2 cm 3) of organs at risk (bladders, rectums, and colons) were analyzed.The quality parameters of the brachytherapy were studied, including conformity index (CI), homogeneity index (HI), and external index (EI) of the target volume.Perioperative complications were also observed. Results:A total of 194 treatments were included.During the treatment, 5-13 (median 6) needles were inserted, with a prescription dose of 5-6 Gy per fraction.There were no statistical differences between pre-plan and intraoperative D90, D100, V100, CI, HI, and EI as well as the D2 cm 3 of bladders and colons at risk ( P>0.05). In contrast, for the D2 cm 3 of rectums, the intraoperative dose was slightly higher than the pre-plan dose, showing a statistical difference ( t=-0.335, P=0.027). Conclusions:The 3D-PIT-assisted and CT-guided 192Ir interstitial brachytherapy at a high dose rate is accurate and feasible in the treatment of recurrent gynecologic tumors, meeting the pre-plan dose requirement.

The role of indocyanine green fluorescence imaging in laparoscopic partial splenectomy / 中华肝胆外科杂志

Objective:To study the role of indocyanine green(ICG)fluorescence imaging in laparoscopic partial splenectomy (LPS).Methods:The data of 4 patients who underwent ICG fluorescence imaging technology for LPS at Beijing Luhe Hospital Affiliated to Capital Medical University from May 2017 to May 2020 were retrospectively analyzed. There were 3 females and 1 male, aged 46, 41, 27 and 12 years respectively. The extents of spleen preservation were compared between ICG fluorescence imaging with ordinary white light during operation. The residual splenic remnants were tested with fluorescence imaging after splenectomy, which showed fluorescence fading indicating good vascular perfusion.Results:ICG fluorescence imaging was performed on 4 patients. The operation time ranged from 180.0 to 250.0 min, and the intraoperative blood loss ranged from 40.0 to 200.0 ml. The postoperative hospital stay ranged from 4 to 14 days. There were no serious complications. Postoperative histopathology showed: splenic cyst ( n=1), splenic hemangioma ( n=2), and splenic laceration ( n=1). Conclusions:ICG fluorescence imaging technology had a significant role to play in partial splenectomy. This study showed this technique to improve safety of laparoscopic partial splenectomy.

Research on Individualized Phantom Based on 3D Printing for Radiotherapy Dose Verification / 中国医疗器械杂志

Dose verification is carried out on the individualized three-dimensional phantom based on 3D printing technology, which simulates the anatomical structure of human body, contour shape, tumor anatomical structure and other dangerous organs to the greatest extent, and produces a reasonable and effective dose validation phantom. According to the need to obtain effective patient data, import Mimics software to reconstruct the parts of the body and its surrounding tissues and organs that need to be measured, and make them into three-dimensional shell components. The 3D printing is used to assemble and fill the equivalent tissue, and then the body phantom is made. The phantom was scanned by CT and the data was transmitted to TPS system. The previously completed treatment plan was transplanted to the phantom. The phantom was placed according to the patient's location information, irradiated and measured data. The three-dimensional shell assembly is completely reconstructed according to the patient's data, and the contour difference is not significant. The shell is filled with tissue radiation equivalent material whose CT value is the same as the average CT value of the shell volume. The CT image data show that the radiation equivalence of the phantom is similar to the actual tissue of the patient, and the equivalent dose distribution conforms to the conventional treatment range. It can provide a reliable means of dose verification for the accurate design of intensity modulated radiation therapy.

Effect of tail vein transplantation of human amniotic mesenchymal stem cells with different transforming growth factor-β expressions on sciatic nerve function in xenografted mice / 中华神经医学杂志

Objective To investigate the effect of tail vein transplantation of human amniotic mesenchymal stem cells (hAMSCs) with different transforming growth factor (TGF)-β expressions on recovery of sciatic nerve function in peripheral nerve xenotransplantation mice.Methods The hAMSCs were isolated from amnion membranes by healthy mother donors and identified by fluorescence activated cell sorter.The up-regulated and down-regulated TGF-β lentiviral plasmids were constructed and transfected into the purified hAMSCs;hAMSCs with stable up-regulated or down-regulated TGF-β expression were constructed.The sciatic nerves of C57BL/6 mice were isolated and cut out,and sciatic nerves of SD rats were isolated and transplanted into the sciatic nerve defected C57BL/6 mice to construct peripheral nerve xeno-transplanted mice models;these mice models were divided into 4 groups (n=10)according to random number table:control group,hAMSCs treatment group,high-expressed TGF-βhAMSCs treatment group,and low-expressed TGF-β hAMSCs treatment group;one d before modeling,phosphate buffer saline (PBS) or hAMSCs re-suspension were drawn with a syringe and slowly pushed into the tail veins of mice for transplantation treatment;14 d after treatment,DigGait analysis system was used to evaluate the recovery of sciatic nerve function in each group of mice.Result Fourteen d after treatment,the sciatic nerve function index (SFI) of the high-expressed TGF-β hAMSCs treatment group (-25.820±0.286) was significantly higher than that of the low-expressed TGF-β hAMSCs treatment group (-33.413±0.920) and hAMSCs treatment group (-30.755±0.421,P＜0.05).Conclusion The tail vein transplantation of hAMSCs with TGF-β high expression can effectively improve the sciatic nerve function in peripheral nerve xenotransplantation mice,which may be a new breakthrough in the treatment of peripheral nerve defects.

Recent advance in role of tissue optical clearing technique in brain serious disorders / 中华神经医学杂志

Tissue optical clearing technique is a novel histological technique that uses a series of physical and chemical methods to process tissue blocks or organs to achieve highly transparent and complete emerging technologies. It can further observe and analyze the internal structure of tissues or organs after combining optical imaging and fluorescent labeling technique. This article will briefly explain the tissue optical clearing technique and introduce the application and prospects of tissue optical clearing technique in brain disorders.

Dosimetric analysis of 3D-printing non-coplanar template combined with CT-guided125I seed implantation for the treatment of spinal metastasis / 中华放射肿瘤学杂志

Objective@#To compare the preoperative and postoperative dosimetric parameters in the treatment of spinal metastasis, and to verify the accuracy of 3D-printing non-coplanar template (3D-PNCT) combined with CT-guided 125I seed implantation for the treatment of spinal metastasis.@*Methods@#The treatment plans of 7 patients with spinal metastasis (9 lesions) from 2016 to 2018 receiving 3D-PNCT in combination with CT-guided 125I seed implantation were retrospectively analyzed. The dosimetric parameters including homogeneity index (HI), conformal index (CI), external index (EI), dose of 90% target volume(D90), mPD, volume percent of 100%, 150%, and 200% prescribed dose V100、V150、V200 and D2cm3 of spinal cord were compared before and after operation. The british columbia cancer ageny particle implantation quality evaluation standard was applied to evaluate the quality of implantation.@*Results@#The HI, EI and CI, D90, mPD, V100, V150, V200 and D2cm3 of spinal cord did not significantly differ before and after the plan (all P>0.05). Five were evaluated as excellent and 4 were assessed as good.@*Conclusion@#The postoperative dosimetric parameters of 3D-PNCT combined with CT guided 125I seed implantation of spinal metastasis are basically consistent with preoperative dosimetric parameters. The postoperative plans are evaluated as excellent or good, suggesting that the technology has a good therapeutic accuracy in the treatment of spinal metastasis.

3D-printing non-coplanar template assisted 125I seed implantation for head and neck tumor: individualized template design and application / 中华放射肿瘤学杂志

Objective To compare the dosimetric data between preoperative plans and postoperative verification in computed tomography (CT)-guided and 3D-printing non-coplanar template-assisted 125I seed implantation for head and neck tumor,aiming to explore the safety,feasibility and accuracy of the individualized template design method.Methods A total of 42 patients with recurrent/metastatic malignant head and neck tumor admitted to Peking University Third Hospital from January to December 2016 were recruited in this study.A prescribed dose of l10-160Gy was adopted.3D-printing non-coplanar templates were designed for 42 cases.The dosimetric parameters including D90,minimum peripheral dose (mPD),V100,V150,V200,conformal index (CI),external index (EI) and homogeneity index (HI) were statistically compared before and after surgery.Results All templates were properly implanted intraoperatively.Compared with preoperative planning,postoperative D90,V100,CI,EI and HI did not significantly differ (P=0.490,0.407,0.893,0.143 and 0.079),whereas mPD,V150 and V200 significantly differed (P=0.036,0.007 and 0.000).Conclusion After postoperative verification,the main dosimetric parameters have high therapeutic accuracy and properly match with preoperative planning,which can meet clinical requirements.

Dosimetric analysis of 3D-printing non-coplanar template combined with CT-guided 125I seed implantation for the treatment of spinal metastasis / 中华放射肿瘤学杂志

Objective To compare the preoperative and postoperative dosimetric parameters in the treatment of spinal metastasis,and to verify the accuracy of 3D-printing non-coplanar template (3D-PNCT)combined with CT-guided 125I seed implantation for the treatment of spinal metastasis.Methods The treatment plans of 7 patients with spinal metastasis (9 lesions) from 2016 to 2018 receiving 3D-PNCT in combination with CT-guided 125I seed implantation were retrospectively analyzed.The dosimetric parameters including homogeneity index (HI),conformal index (CI),external index (EI),dose of 90％ target volume (Dg0),mPD,volume percent of 100％,150％,and 200％ prescribed dose V100、V150、V200 and D2cm3 of spinal cord were compared before and after operation.The british columbia cancer ageny particle implantation quality evaluation standard was applied to evaluate the quality of implantation.Results The HI,EI and CI,Dg0,mPD,V100,V150,V200 and D2cm3 of spinal cord did not significantly differ before and after the plan (all P＞0.05).Five were evaluated as excellent and 4 were assessed as good.Conclusion The postoperative dosimetric parameters of 3D-PNCT combined with CT guided 125I seed implantation of spinal metastasis are basically consistent with preoperative dosimetric parameters.The postoperative plans are evaluated as excellent or good,suggesting that the technology has a good therapeutic accuracy in the treatment of spinal metastasis.

Dosimetry evaluation of three-dimensional-printing template guided radioactive seeds implantation assisted by navigation system in malignant tumors / 中华核医学与分子影像杂志

Objective:To compare the difference of preoperative and postoperative plans of navigation-assisted three-dimensional (3D)-printing template combined with CT-guided radioactive 125I seeds implantation for malignant tumors, and verify preliminarily the plan quality of optical navigation-assisted seeds implantation. Methods:From December 2018 to November 2019, a total of 20 patients (10 males, 10 females, median age: 60.5 years) with malignant tumors received navigation-assisted 3D-printing template combined with CT-guided radioactive 125I seeds implantation in Peking University Third Hospital. Eight cases were implanted in the head and neck, 1 case in the chest wall, 9 cases in the pelvis and 2 cases in the paravertebral and/or retroperitoneal region. The median prescription dose was 150 Gy. The data in the preoperative and postoperative plans was compared, including seeds number, needles number, and some dosimetry parameters. Dosimetry parameters including dose delivered to 90% gross tumor volume (GTV) ( D90), percentage of GTV received 100%, 150%, and 200% of the prescribed dose ( V100, V150, V200), minimum peripheral dose (MPD), conformal index (CI), external index (EI), homogeneity index (HI) of target volume, and 2 cm 3 range of spinal cord receiving dose ( D2 cm 3). Paired t test and Wilcoxon signed rank test were used to analyze the data. Results:The needles number of preoperative and postoperative plans was the same (both 12 (9, 19)), and the seeds number of postoperative plan was more than preoperative plan with no significant difference (51(35, 68) vs 49(35, 63); z=1.859, P>0.05). The MPD of postoperative plans was higher than preoperative plans ((80.52±14.89) vs (67.22±20.56) Gy, t=-3.769, P=0.001). There were no significant differences in other dosimetry parameters between the two plans ( t values: -0.533, -0.423, z values: from -0.849 to 1.416, all P>0.05). Postoperative dose quality assessment was excellent in 17 cases (17/20), good in 2 cases (2/20) and middle in 1 case (1/20). Conclusions:The quality of the implantation is good under the guidance of combined mode. The actual target dose after operation can meet the requirements of preoperative planning.