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Objective:To evaluate the biomechanical stability of our slot-designed compression bolt (SCB) combined with bilateral locking compression plates (LCPs) in the treatment of intra-articular distal femur fracture.Methods:In 24 adult male knee specimens treated with formalin, the femoral bony part was preserved to establish standard models of intra-articular distal femur fracture (AO type 33-C1). According to the random number table, the fracture models were divided into 2 equal groups: an experimental group ( n=12) subjected to fixation with one SCB combined with bilateral LCPs with 10 locking screws and a control group ( n=12) subjected to fixation with bilateral LCPs with 12 locking screws. In each model, a vertical ballast test was conducted to record the maximum axial displacement of the system and a horizontal torsion test to calculate the torsional stiffness of the system. When the loading pressure was 0-1,000 N in the biomechanical machine, structural abnormalities were observed in the 2 groups of models and the system maximum axial displacement and system torsional stiffness were compared between the 2 groups. Results:When the vertical ballast pressure was 400 N, 600 N, 800 N and 1,000 N, the maximum axial displacement of the system was, respectively, (0.14±0.01) mm, (0.25±0.01) mm, (0.41±0.02) mm and (0.63 ± 0.02) mm in the experimental group, and (0.15 ± 0.01) mm, (0.26 ± 0.01) mm, (0.46 ± 0.03) mm, and (0.67 ± 0.04) mm in the control group. Compared with the control group, the average maximum axial displacement in the experimental group decreased significantly under the axial pressure of 600-1,000 N ( P<0.05). When the horizontal torsion reached 5°, the torsional stiffness was, respectively, (2.00±0.12) Nm/° and (2.02±0.07) Nm/° in the experimental group and the control group, showing no significant difference between the 2 groups ( P>0.05). Conclusions:In the treatment of intra-articular distal femur fracture, compared with simple bilateral LCPs, our SCB combined with bilateral LCPs demonstrate similar torsional stability but better axial biomechanical stability. As our SCB has advantages of bilateral compression and minimal invasion in operation, it may be a new option for the reduction and compression treatment of intra-articular fractures.
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Objective:To explore the application value of wide detector multi-slice spiral CT target scanning technique in the preoperative evaluation of pancreatic cancer.Methods:The clinical data of 22 patients with pancreatic cancer who underwent pancreatic arterial contrast enhanced CT scanning and were diagnosed by pathology in the First Affiliated Hospital of Naval Medical University from September 2019 to October 2019 were analyzed retrospectively. The CT phantom experiment was carried out on the international standard phantom CATPHON500. By changing the scanning radiation dose, scanning mode and scanning field of view, the spatial resolution and density resolution of the image were compared and analyzed. The target scan technical parameters obtained from the experiment were applied to the late arterial phase of MDCT enhanced scan in 22 patients with pancreatic cancer. Executive current, volume scanning mode and small scanning field were used for scanning. The attenuation value (CT value) and noise value (SD value) of pancreatic cancer tissue and normal pancreatic tissue were measured at different phases, the attenuation difference and contrast signal-to-noise ratio (CNR) of the two tissues were calculated, the contrast difference between the two tissues was evaluated, and the CT values of celiac trunk, renal artery and vein, superior mesenteric artery and vein, splenic vein and portal vein were measured, and the display of tumor tissue and peripancreatic important vessels was evaluated.Results:In the phantom experiment, under the condition of the same radiation dose, the image quality of the volume scan mode was better than that of the spiral scan mode (1%@4 mm versus 1%@9 mm at 5 mGy and 1%@2 mm versus 1%@6 mm at 25 mGy). In comparison between pancreatic tumor and pancreatic tissue, the enhancement process of pancreatic tumor tissue was increased at first and then decreased, while that of pancreatic tumor tissue was slightly enhanced. The attenuation difference between pancreatic tissue and tumor tissue and CNR also increased at first and then decreased, reaching the maximum at the late arterial stage [(91.96±29.29)HU, 8.60±5.71]. The differences between each phase were statistically significant ( F values were 47.20 and 19.80 respectively, all P values <0.05). The evaluation of vascular variation and invasion showed that a better arterial phase image could be obtained on the late arterial target scan images, while taking into account the display of splenic vein, mesenteric vein and portal vein. Conclusions:The wide detector MDCT target scanning technique can improve the spatial resolution and density resolution of the image, greatly improve the contrast between tumor tissue and peripancreatic tissue and blood vessels, and provide more accurate tumor staging and resectability evaluation information for preoperative evaluation of pancreatic cancer.
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Objective To investigate the efficacy and safety of stereotactic body radiation therapy (SBRT) for very elderly patients with pancreatic cancer.Methods The clinical data of a total of 149 patients aged from 75 to 90 years with locally advanced or metastatic pancreatic cancer treated by SBRT in Changhai Hospital from January 2012 to December 2016 were retrospectively reviewed.Prescription doses ranged from 3.6-9Gy/fractions,and the total doses were 19.5-49Gy in 3-8 fractions.The level of serum cancer antigen 19-9(CA19-9) before and 3 months after treatment was compared and the radiotherapy biological effective dose (BED10) was calculated.The adverse events of the radiotherapy were observed.Overall survival (OS) and progression-free survival (PFS) were recorded through follow-up,and the factors influencing the patients' survival were investigated by univariate and multivariate analysis.Results All the patients' median OS and PFS were 12.9and 8.3 months,respectively.One-year OS and PFS rate were 55.9％ and 19.5％,respectively.Tumor stage and the decrease of CA19-9 levels ＞50％ at 3 months after treatment and BED10 were independent factors of OS and PFS.No grade 3 or higher toxicities were recorded in all the patients.Conclusions SBRT is safe and effective for very elderly patients with locally advanced or medically inoperable pancreatic cancer.Tumor stage,the decrease of CA19-9 levels after treatment and BED10 were associated with prognosis.
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<p><b>OBJECTIVE</b>To evaluate the effects of needling depth on clinical efficacy of lumbar disc herniation (LDH).</p><p><b>METHODS</b>Ten electronic databases, including China National Knowledge Infrastructure (CNKI), VIP Database, Chinese Biomedical Literature Database (CBM), Wanfang Database, MEDLINE, CENTRAL, CINAHL PLUS, AMED, Embase, PsycINFO, and 6 registry platforms of clinical trials were searched. All randomized controlled trials (RCTs) that compared the effect of needling depth on clinical efficacy of LDH were collected; in addition, the reference lists of the studies included were hand searched. Data were extracted independently by two reviewers. RevMan 5.3 was applied to carry out statistical analysis.</p><p><b>RESULTS</b>Totally 8 716 articles were retrieved, and 10 RCTs were included after screening, involving 1 116 patients. The results showed the effects of deep acupuncture onrelievingpain, reducing the Oswestry disability index (ODI), improving total effective rate and Japanese Orthopaedic Association (JOA) were superior to those of shallow acupuncture in patients with LDH.</p><p><b>CONCLUSION</b>It is preliminarily indicated that deep acupuncture is helpful to improve the therapeutic effect of LDH; however, due to the low research quality and small sample size, the evidence is insufficient, and more high-quality researches are needed to further confirm the results.</p>
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Objective To explore the optimal delay time of enhanced scanning with CT based simulation before cyberknife treatment of carcinoma in different positions of the pancreas.Methods Philips 16 large aperture spiral CT scan was applied.Fifty-three patients with carcinoma in the head of the pancreas and 60 pancreatic cancer patients in the body or tail were randomly assigned to three groups with scan delays of 25,45,and 65 seconds in group A (25s group,pancreatic head n =18,pancreatic body or tail n =21);30,50,and 70 seconds in group B (3 0s,pancreatic head n =17,pancreatic body or tail n =19);and 35,55,and 70 seconds in group C (35s,pancreatic head n =18,pancreatic body or tail n =20),respectively.Images were evaluated by three associate professors of radiation oncology based on image quality score scale.The items rating in different time points were compared using a random intercept model of mathematical mean in three groups.Then the items rating of different time points were compared in pairs using the Sidak method.One-way ANOVA was used to compare the optimal time point of each group,so the optimal delay time of enhanced scanning with CT based simulation before cyberknife treatment of pancreatic cancer was obtained.Results The delayed time points with the highest scores for target delineation of the tumor in the pancreatic head and the pancreatic body or tail by CT enhanced scanning in three groups were 45 s/65 s,50 s/50 s,55 s/75 s,respectively.There was no significant difference in the scan time of 45 s,50 s and 55 s for the tumor in the pancreatic head.Similarly,no significant difference could be found in the scan time of 65 s,50 s and 75 s for the tumor in the pancreatic body and tail.Conclusions The recommended delay time interval for localizing the tumor in pancreatic head by CT enhanced scanning was 45 ～ 55 s,and for the tumor in the pancreatic body or tail was 50 ～75 s.
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Objective To assess the optimal delay time of enhanced scanning with CT-based simulation before cyberknife treatment for pancreatic cancer and to analyze the correlations between the target delineation and the rating items.Methods One hundred and twenty pancreatic cancer patients underwent Philips 16 big core spiral CT before cyberknife treatment.Patients were assigned to three groups randomly with scan delays of 25,45 and 65 s;30,50 and 70 s;and 35,55 and 75 s respectively.After the scanning,the images were evaluated by three associate professors in the field of radiation oncology.To achieve the optimal delay time,the data were compared with a random intercept model of mathematical mean,the Sidak method and One-way ANOVA.Pearson method was used to analyze the correlations between the target delineation and the rating items.Results The tumor boundaries,retroperitoneal lymph nodes,duodenal images,accuracy of target volume delineations in 45 and 65 s,50 and 70 s,55 and 75 s items rating difference had no statistically significant differences (P ＞ 0.05),but significantly superior to those in 25,30,35 s groups respectively(t =3.59-21.68,13.34-15.46,12.42-13.83,P ＜0.05).Therefore,the proposed delay time interval was 50-65 s,and the average value of the target volume delineation was the highest in 55 s group (3.91-± 0.50).When the scan delay time was 55 s,the target delineation was positively correlated with the tumor boundary (r =0.914 4,P ＜ 0.05),and negatively related to the value of other imaging (r =-0.926 3,P ＜ 0.05).Conclusions The recommended delay time interval of pancreatic cancer before cyberknife treatment CT enhanced scanning was 50-65 s,and the optimal time point was 55 s.The target volume delineation was positively correlated with the boundary of the tumor,and significant negatively related to the value of other imaging.
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Radiation therapy is one of the main means of treatment for non-small cell lung cancer (NSCLC). With the rapid development of modern technology, three dimensional conformal radiotherapy, intensity modulated radiotherapy, stereotactic radiotherapy play a very important role in this field. The use of the state-of-art radiation modality can definitely improves the accuracy of the treatment, which results in improving the local control rate of tumor and reducing the adverse reaction of normal tissue. Advances in modern imaging device and its clinical application is the premise of precise radiotherapy. Positron emission tomography and computed tomography (PET-CT) can effectively provide anatomical and functional information; it plays a more and more important role in the diagnosis of NSCLC before radiotherapy, the process of precise target delineation and also the evaluation of therapeutic efficacy after radiotherapy.
