Short Diameter Research Articles

Clinical Analysis of Recurrence Patterns in Patients With Nasopharyngeal Carcinoma Treated With Intensity-Modulated Radiotherapy.

To evaluate the characteristics and risk factors for locoregional recurrence in patients with nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT). The clinical diagnosis and treatment data of 195 patients with NPC treated with IMRT from March 2005 to May 2010 (including 9, 24, 70, and 92 cases of stage I, II, III, and IV disease, respectively, according to the 7th edition American Joint Committee on Cancer staging criteria) were retrospectively analyzed. The Kaplan-Meier method was used for survival analysis, and logistic regression was used to conduct univariate and multivariate analyses. The 5-year recurrence rate was 10.8%, and the 5-year local and regional recurrence rates were 8.7% and 3.4%, respectively. Multivariate analysis showed that the short axis of the cervical lymph nodes (≥3 cm) was an influencing factor for regional lymph node recurrence after IMRT. In-field and high-dose region failures were the main patterns associated with local-regional recurrence, and nasopharyngeal recurrence was most commonly detected. Newly diagnosed patients with large cervical lymph nodes (short diameter ≥3 cm) should be carefully followed up considering regional lymph node recurrence.

Serial Follow-Up Evaluation With Computed Tomography After Conservative Medical Treatment in Patients With Symptomatic Spontaneous Isolated Superior Mesenteric Artery Dissection.

There is no detailed information available about trend in the morphological change after conservative medical treatment in patients with symptomatic spontaneous isolated superior mesenteric artery dissection (SISMAD). We enrolled 27 consecutive patients with symptomatic SISMAD who underwent conservative medical treatment between 2006 and 2015. The long-term prognosis, natural history, and serial follow-up computed tomography (CT) findings of risk factors of rupture such as arterial diameter and false lumen enhancement were retrospectively assessed. Spontaneous isolated superior mesenteric artery dissection usually developed in middle-aged men around 50 years old who had a history of smoking. Follow-up CT was performed at 1 to 6 months, 7 to 12 months, and after 12 months. Superior mesenteric artery (SMA) maximum diameter was 10.3 mm (quartile 9.5-11.3) on initial CT and expanded in 47.1% patients during 1- to 6-month follow-up, which decreased over time ( P < .001 at 7- to 12-month follow-up, P = .001 after 12-month follow-up). On the other hand, false lumen enhancements were revealed in 9 (33.3%) patients on initial CT. The size of false lumen enhancement was expanded in the longest diameter in 35.3% patients and in shortest diameter in 29.4% during 1- to 6-month follow-up. However, the size of false lumen decreased in all patients after 12-month follow-up. All patients were alive without arterial aneurysm rupture and hospital readmission during the median of 523 days (170-799) study period. We demonstrated that both SMA maximum diameter and false lumen enhancement were transiently expanded in some patients during 6-month follow-up, but no longer expanded after 12-month follow-up. Patients with symptomatic SISMAD could be treated medically with scheduled careful follow-up CT evaluations.

Application of 2- and 3-Dimensional Sonography Using the Virtual Organ Computer-Aided Analysis Technique to Measure the Hippocampal Formation and Its Correlation With Corrected Gestational Age in Neonates.

The purpose of this study was to use transcranial 2- and 3-dimensional sonography with the Virtual Organ computer-aided analysis (GE Healthcare, Milwaukee, WI) technique to observe the morphologic characteristics of the hippocampal formation and to analyze its correlation with the corrected gestational age. Transcranial sonography was performed from the sagittal plane of the anterior fontanel to the sagittal plane of the posterior horn of the lateral ventricle. The morphologic characteristics of the hippocampal formation in 183 singleton neonates with a corrected gestational age of 32 to 43 weeks were observed. The long diameter, short diameter, area, and perimeter of the hippocampal formation were all quantitatively measured. The volume of the hippocampal formation was measured by 3-dimensional sonography using the Virtual Organ computer-aided analysis technique. The correlation between the corrected gestational age and each parameter was analyzed. The display rate of the hippocampal formation was 100% in the neonates with a typical hippocampus shape. In healthy neonates with a corrected gestational age of 32 to 43 weeks, the long and short diameters, area, perimeter, and volume of the hippocampal formation were all positively correlated with the gestational age. Transcranial sonography could be used as a conventional approach for evaluation of the development of the hippocampal formation in neonates.

Clinical application of tunnel technique on endoscopic submucosal dissection for colorectal laterally spreading tumor

Objective To investigate the clinic effect of tunnel technique on endoscopic submucosal dissection (ESD) for massive colorectal laterally spreading tumor (LST). Methods A retrospective study was conducted on the data of patients with colorectal large area LST (the shortest diameter>4 cm) undergoing ESD by tunnel technique from January 2015 to June 2016 in Digestive Endoscopy Center of Jiangsu Province Hospital of Traditional Chinese Medicine. The size of resected specimens, operation time, complications, pathology results, the number of en bloc resection and curative resection were analyzed. Results A total of 14 cases were collected, including 7 males and 7 females. The longest diameters of resected specimens were from 4.0 to 7.0 cm with mean size of 5.18±0.49 cm. The operation times were from 40 to 120 min with mean time of 63.57±12.95 min. Intraoperative perforation occurred in 2 cases but no delayed perforation and bleeding occurred. Postoperative pathology showed 1 patient with adenoma hyperplasia with crypt abscess, 3 patients with low grade intraepithelial neoplasia, 6 patients with high grade intraepithelial neophasia, 1 patient with carcinoma in situ, 1 patient with carcinoma in M3, and 2 patients with carcinoma in SM1. The number of cases who received en bloc resection, complete resection, and curative resection were 13, 13, and 13, respectively. Conclusion ESD by tunnel technique is safe and effective in the treatment of colorectal large area LST, which is worth popularizing in clinics. Key words: Therapeutic endoscopy; Endoscopic submucosal dissection; Tunnel technique; Colorectal laterally spreading tumor

Application value on localization and evaluation of sentinel lymph nodes in early-stage breast cancer with CT lymphography

Objective: To explore the clinical value of CT lymphography (CT-LG) on the localization and evaluation of sentinel lymph node (SLN) in patients with early-stage breast cancer. Methods: Thirty-six patients with early-stage breast cancer were enrolled in this study from September 2014 to June 2016 in the First Hospital of Zhengzhou University.The diagnoses were confirmed by puncture or local surgical pathology with negative clinical palpation of axillary lymph nodes, and sentinel lymph node biopsy (SLNB) was planned.The patients received CT-LG examination.The first one or several lymph nodes along the lymph duct draining from the injection site to axilla was/were defined as SLN(s), and the results were compared with the SLNB.Wilcoxon signed ranks test was used to compare the number of SLN detected by CT-LG and SLNB; according to the pathologic results, Student t test or chi-square test was used to compare the differences of the positive SLNs with negative ones. Results: SLNs were successfully identified in all 36 patients, 32 cases (88.9%) had high-quality images (with both SLN and lymphatic vessel visible); 36 SLNs were located by CT-guided wire with a success rate of 100%.A total of 88 SLNs were identified by CT-LG in 36 patients, and 102 SLNs were obtained by SLNB (Z=-2.646, P=0.008). The long-short diameter ratio (L/S) of SLN obtained by SLNB was significantly smaller than that of CT-LG (1.7±0.3 vs 1.9±0.4, t=2.880, P=0.004). Compared with pathology, CT-LG showed 21 positive SLNs and 67 negative SLNs, and the short diameter of positive SLNs was bigger than that of negative ones[(5.9±2.1) vs (4.8±1.8) mm, t=2.235, P=0.028]. Of 67 negative SLNs, 61(91.04%) appeared homogenously contrast agent filling, and 13(61.90%) of the 21 positive SLNs were found filling defect changes, and the differences in filling defect changes between positive and negative SLNs were statistically significant (χ(2)=26.479, P<0.001). Conclusion: CT-LG can accurately locate the SLN for early-stage breast cancer, and both the short diameter and filling defect changes can help evaluate the status of SLN.

Study on normal ophthalmic tissues among ocular volume and extraocular muscles structure measurement by HR-MRI

Objective: To measure the ocular volume and extraocular muscles of healthy people using the high-resolution magnetic resonance imaging (HR-MRI) technology, to provide parameters support for eye research, teaching and diagnosis. Methods: The study collected 100 cases of normal subjects (200 eyes) from November 2012 to December 2013, including 50 males and 50 females, accepted line HR-orbital MRI, and image processing software was applied to morphology and statistical analysis. The extraocular muscles, muscle belly level horizontal diameter and maximum diameter vertical diameter were measured. Results: The volume of the vitreous cavity (4.51 ± 0.26) cm 3 had no significant difference with the anatomic normal value ( p = .148); The volumes of the ocular globe, the anterior chamber and the lens cavity were (5.05 ± 0.21) cm 3 , (0.24 ± 0.26) cm 3 , (0.23 ± 0.14) cm 3 , with no statistic differences compared with those of the anatomic normal values. The extraocular muscles of normal Chinese were symmetrical on the two sides. The relationships of the short diameters of extraocular muscles in the maximum planes were: inferior rectus muscle (IR) > medial rectus muscle (MR) > superior rectus (SR) > lateral rectus muscle (LR). Those of the long diameters of extraocular muscles were: LR > MR > SR > IR. Conclusions: MRI can be used for measuring ocular volume and sizes of extraocular muscles. Compared with the anatomic normal value, the sizes of extraocular muscles can also be assessed by the symmetry on the two sides and by observing the usual rule of extraocular muscles.

An Adaptive Parallel Algorithm for Computing Connected Components

We present an efficient distributed memory parallel algorithm for computing connected components in undirected graphs based on Shiloach-Vishkin’s PRAM approach. We discuss multiple optimization techniques that reduce communication volume as well as load-balance the algorithm. We also note that the efficiency of the parallel graph connectivity algorithm depends on the underlying graph topology. Particularly for short diameter graph components, we observe that parallel Breadth First Search (BFS) method offers better performance. However, running parallel BFS is not efficient for computing large diameter components or large number of small components. To address this challenge, we employ a heuristic that allows the algorithm to quickly predict the type of the network by computing the degree distribution and follow the optimal hybrid route. Using large graphs with diverse topologies from domains including metagenomics, web crawl, social graph and road networks, we show that our hybrid implementation is efficient and scalable for each of the graph types. Our approach achieves a runtime of 215 seconds using 32 K cores of Cray XC30 for a metagenomic graph with over 50 billion edges. When compared against the previous state-of-the-art method, we see performance improvements up to 24 $\times$ .

O208 Evidence by direct current stimulation (tDCS) of cerebellum involvement in pain perception and modulation in humans

Objective cerebellum is involved in a wide number of integrative functions; its role in pain processing has been scarcely investigated. We tried to clarify this aspect using transcranial cerebellar direct current stimulation (tcDCS) and studying changes in perceptive threshold (PT), pain intensity (VAS) and laser evoked potentials (LEPs) responses (N1 and N2/P2). Materials and methods Fifteen subjects were studied before and after anodal, cathodal and sham tcDCS. LEPs were obtained using a Nd:YAP laser; signals were amplified, band pass filtered. The left hand dorsum was stimulated by laser pulses with short duration (5 ms) and small diameter spots (5 mm). VAS was evaluated by delivering laser pulses at two different intensities, respectively two and three times the pain threshold (PT). Results Cathodal polarization dampened the PT and increased the VAS score, while the anodal one had opposite effects ( p p Discussion tcDCS modulates pain perception and its cortical correlates. As it is effective on N1 and N2/P2 components and these responses are generated by parallel and partially segregated spinal pathways reaching different cortical targets, we speculate that the cerebellum modulates the activity of both somatosensory and cingulate cortices, interfering with the sensory-discriminative as well as emotional dimensions of pain. Conclusions Present findings prove Cerebellum involvement in pain processing and prompt further investigations on tcDCS employments as novel therapeutic tool in chronic pain patients.

Use of Breast Magnetic Resonance Imaging and Ultrasonography for Identifying Nonpalpable Axillae Metastases in Newly Diagnosed Breast Cancer Patients

BackgroundThe metastasis of axillary lymph node (ALNs) is a critical step in the initial cancer staging of newly diagnosed breast cancer (BC) patients. Various imaging modalities can enhance the sensitivity of clinical examination in assessing the ALN status. Patients and MethodsWe enrolled 135 patients with BC, confirmed via histopathology, including 4 bilateral BC cases. A total of 139 ipsilateral ALNs adjacent to the breast lesion were examined via physical examination, ultrasonography (US), and magnetic resonance imaging (MRI); of these, 100 were nonpalpable ALNs, as determined by experienced breast surgeons and physicians. The relative size parameters on MRI and US images were recorded. Receiver operating characteristic (ROC) analyses were conducted, and the area under the ROC curve (AUC) was compared. ResultsOf 139 ALNs, 67 (48%) were malignant and 72 (52%) were benign on pathological examination. In all of the ALNs, the US short diameter appeared to be the most discriminative quantitative measurement for detecting positive findings (AUC, 0.854). In nonpalpable ALNs as well, the US short diameter exhibited the greatest discriminability (AUC, 0.746). However, the 2-dimensional and 3-dimensional parameters on MRI did not exhibit any significant differences between the enrolled and nonpalpable ALNs (P > .05). ConclusionThe shortest diameter on US exhibited better discriminative ability than MRI for predicting positive ALNs in nonpalpable axillae. Moreover, the 2-dimensional and 3-dimensional parameters on MRI did not differ in terms of discriminability.

A novel segmentation of cochlear nerve using region growing algorithm

Abstract Sensorineural hearing loss is a hearing impairment which occurs when there is damage to the inner ear, or to the nerve pathways from the inner ear to the brain. Cochlear implants have been developed to benefit children with bilateral or unilateral Sensorineural hearing loss. A very small or absence of cochlear nerve precludes successful outcome of cochlear implant surgery. Hence, segmentation and measurement of the cochlear nerve support the surgeon’s decision to predict a normal or poor outcome of the cochlear implant. For this purpose, a modified region growing segmentation algorithm is proposed that segments the cochlear nerve region accurately. The segmentation accuracy is evaluated using parameters like Jaccard, Dice, False Positive Dice, and False Negative Dice. The segmented region is measured and evaluated using long diameter, short diameter, and cross-sectional area. The statistical analyses of intra/inter-observer correlation and limits of agreement are performed on a cross-sectional area of the cochlear nerve to investigate the reproducibility of the automated measurement.

Morphometric evaluation of facial and vestibulocochlear nerves using magnetic resonance imaging: comparison of Menière’s disease ears with normal hearing ears

Loss of neural structures (such as hair cells or neurones within the spiral ganglion) has been proposed to be involved in Menière's disease (MD) (Spoendlin et al. Acta oto-laryngologica Supplementum 499:1-21, 1; Merchant et al. Eur Arch Oto-Rhino-Laryngol Off J Eur Feder Oto-Rhino-Laryngol Soc (EUFOS) Affil German Soc Oto-Rhino-Laryngol Head Neck Surg 252(2):63-75, 2; Tsuji et al. Ann Otol Rhinol Laryngol Suppl 81:26-31, 3; Kariya, Otol Neurotol Off Publ Am Otol Soc Am Neurotol Soc Eur Acad Otol Neurotol 28(8):1063-1068, 4; Megerian Laryngoscope 115(9):1525-1535, 5) but this has yet to be confirmed. Therefore, the aim of this study was to investigate morphometric changes of VIIth and VIIIth cranial nerve in MD. MD is characterized by episodic vertigo, tinnitus, fluctuating hearing loss, and aural fullness. The exact pathophysiological mechanisms involved such as viral infections, autoimmune processes, genetic predisposition, cellular apoptosis, and oxidative stress are still not clear. Using a T2-weighted 3D-GE "constructive interference in steady state" (CISS) 3T magnetic resonance imaging (MRI) sequence, we evaluated the properties of the VIIth and VIIIth cranial nerves as they passed from the cerebellopontine angle to the inner ear modiolus. 21 patients with MD were examined along with 39 normal controls. Bidirectional nerve diameters and cross-sectional areas (CSA) were measured in a transverse plane. The comparison of study and control group showed statistically significant (P<0.000595 after Bonferroni correction) differences between the CSA measurements. The facial, cochlear, superior vestibular, and inferior vestibular nerves (FN, CN, SVN, IVN) of MD patients were significantly larger than those of the control group, both on the MD-affected side and on the healthy side. Thus for example, the cochlear nerve CSA measurements were 0.69±0.14mm2 (P<0.0001) in the affected ears of the unilateral MD group, 0.70±0.12mm2 (P<0.0001) in the affected ears of the cohort including the bilateral MD group, 0.71±0.13mm2 (P<0.0001) in the non-affected ears of the MD patients, as compared to 0.46±0.14mm2 in the control group. The perpendicular nerve diameters were found to vary according to site of measurement and type of measurement used. For example a statistically significant enlargement of the short diameter measurements of the SVN at the level of the meatus was found, but not of long diameter measurements at the same site. Although cellular death would theoretically be expected to lead to a decreased nerve thickness, our data showed a swelling of cranial nerves VII and VIII within the study group compared to our normal hearing control group. The similar reaction of the facial nerve supports mediator-based theories of MD pathophysiology.

Effect of ascending aortic dimension on acute procedural success following self-expanding transcatheter aortic valve replacement: A multicenter retrospective analysis

AimsSelf–expanding (SE) valves are characterized with long stent frame design and the radial force of the device exists both in the inflow and outflow level. Therefore, we hypothesized that device success of SE-valves may be influenced by ascending aortic dimensions (AAD). The aim of this study was to determine the influence of AAD on acute device success rates following SE transcatheter aortic valve replacement (TAVR). Methods & ResultsIn 4 centers in the United States and Asia, 214 consecutive patients underwent SE-TAVR. Outcomes were assessed in line with Valve Academic Research Consortium criteria. AAD was defined as the sum of the short and long axis aortic diameter divided by 2. Overall, device success rate was 85.0%. Multivariate analysis revealed that increased AAD (Odds ratio 1.27) and % oversizing (Odds ratio 0.88) were found to be independent predictors of unsuccessful device implantation. The c-statistic of the model for device success was area under the curve 0.79, sensitivity 81.3% and specificity 44.0%. Co-existence of several risk factors was associated with an exponential fall to 64.2% in device success rate. For a large AAD, however, optimally oversized SE-valves (threshold 16.2%) resulted with high device success rates compared to suboptimal oversizing (88.6% vs. 64.2%, p=0.005). ConclusionsLarger AAD and smaller degrees of oversizing were confirmed to be the most relevant predictors of unsuccessful device implantation following SE-valve implantations. Optimal oversizing of great significance was noted, particularly that with a large AAD.

Endoscopic ultrasound-guided fine-needle aspiration and cytology for differentiating benign from malignant lymph nodes

Background and study aimsIntra-abdominal and mediastinal lymphadenopathy are often difficult to diagnose, particularly in the absence of a primary lesion. Endosonography (EUS)-guided fine-needle aspiration and cytology (FNAC) has provided an easy and safe access to these lymph nodes, sparing the use of invasive and costly interventions. The main aim of this study is to assess the specificity, sensitivity, and predictive value of EUS-guided FNAC in the diagnosis of benign and malignant lymph nodes. In addition, the study aims to determine significant EUS features that could help in predicting lymph node malignancy. Patients and methodsThis prospective study included 142 patients with intra-abdominal or intrathoracic lymphadenopathy who were referred for EUS-guided FNAC because of inaccessibility by other imaging modalities. Ninety (63.3%) patients were found to have malignant lymph nodes, and 52 (36.6%) had lymphadenopathy of benign nature. ResultsEUS-guided FNAC had a sensitivity and specificity of 92% and 100% respectively. It had positive and negative predictive values of 100% and 88% for malignancy, respectively. By logistic regression analysis, EUS features and shortest diameter were found to be potential predictors of malignancy with p-value of <0.0001. ConclusionEUS-guided FNAC is a powerful modality in the diagnosis of benign and malignant lymph nodes. Additional complementary EUS features could be added to this technique for definitive diagnosis.

Aortoventricular annulus shape as a predictor of pacemaker implantation following transcatheter aortic valve replacement

Conduction abnormalities following transcatheter aortic valve replacement (TAVR) are caused by damage of the aortoventricular conduction tissue during positioning of the valve. Therefore, our aim was to assess whether a higher difference between the long and short diameters of the elliptic aortoventricular annulus will possess higher forces on the annulus, and thus will be a predictor of pacemaker need following TAVR. We retrospectively analyzed 123 patients who had the aortoventricular annulus measured by computed tomography angiography. The difference between maximal (Dmax) and minimal (Dmin) diameters of the annulus was considered the elliptic factor (ELFA), which was analyzed using t test to evaluate whether it differs between the group who received a pacemaker and the group without the need for a pacemaker. Then, using univariate and multivariate models adjusted for other confounders predicting the need for a pacemaker, we sought to evaluate whether a higher ELFA is a predictor of pacemaker implantation. Mean age was 82.2 ± 6.4 years, and 62.6% were women. Average Dmax, Dmin and ELFA were 25.8, 20.8 and 5 mm, respectively. Fourteen patients (11.4%) underwent pacemaker implantation. Those patients had an ELFA of 5.9 mm compared with 4.9 mm in those who did not receive a pacemaker (P < 0.01). In multivariate analysis, a higher ELFA remained a statistically significant and independent predictor for the need of a pacemaker (P = 0.046). A high ELFA is an independent and significant predictor of the need for pacemaker implantation after TAVR and suggests further investigation whether it should be considered as a factor in managing TAVR patients.

Value of 18F-FDG PET-CT in detection of primary lesion and pelvic lymph node metastasis in FIGO stages ⅠA2-ⅡA cervical cancer

To assess the value of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-CT (PET-CT) in detection of primary tumor and pelvic lymph node metastasis in International Federation of Gynecology and Obstetrics (FIGO) stages ⅠA2-ⅡA cervical cancer. The clinical data of 91 patients with FIGO stagesⅠA2-ⅡA cervical cancer were retrospectively analyzed. The sensitivity of 18F-FDG PET-CT in detection of cervical cancer was calculated. The long diameter, short diameter and SUVmax were compared between metastatic lymph nodes (MLN) and non-metastatic lymph nodes (NMLN). The optimal cut-off values of different indexes were determined by receiver operating characteristic (ROC) curve and area under curve (AUC), and the sensitivity, specificity and accuracy were calculated. 18F-FDG PET-CT examinations were positive in 89 patients (89/91, 96.7%). The short diameters of NMLN and MLN were (6.50±2.31)mm and (4.21±1.49)mm(t=4.855, P<0.05); the SUVmax of NMLN and MLN were 4.56±3.34 and 1.92±1.41(t=31.685, P<0.05). ROC AUCs of the short diameter and SUVmax in diagnosis of metastatic lymph nodes were 0.802 and 0.861. Taken short diameter ≥ 5.05 mm and SUVmax ≥ 2.05 as cut-off values, the corresponding sensitivity, specificity and accuracy in diagnosis of metastatic lymph nodes were 85.0%, 93.0% and 86.8%, respectively. 18F-FDG PET-CT is sensitive to detect primary lesion and pelvic lymph node metastases in FIGO stages ⅠA2-Ⅱ A cervical cancer, and the highest diagnostic accuracy may be obtained by taking short diameter ≥ 5.05 mm and SUVmax ≥ 2.05 as the standard.

Diagnostic value of dual energy CT for lymph node metastasis in patients with non-small cell lung cancer

To assess the diagnostic value of dual energy CT for lymph node metastasis in patients with non-small cell lung cancer (NSCLC). Forty NSCLC patients, including 15 cases of squamous cell carcinoma and 25 cases of adenocarcinoma, underwent dual energy CT examination in pre-contrast and venous phase contrast scans, then the CT attenuation value of the lung cancer lesions and 85 mediastinal enlarged lymph nodes (the short diameter ≥ 5 mm, 53 metastatic and 32 non-metastatic) were measured at different energy levels (40-190 keV, spacing 10 keV) in venous phase contrast. CT spectral curves of the lung cancer lesions, hilus pulmonis and mediastinal enlarged lymph nodes were produced automatically, through comparing their CT spectral curves slope to judge whether or not the lymph nodes were metastatic. Receiver operating characteristic (ROC) curve was used to evaluate the efficiency of CT spectral curve in diagnosis of lymph node metastasis. The CT spectral curves slopes of the lung cancer, metastatic lymph nodes and non-metastatic lymph nodes were 1.10±0.11, 1.08±0.07 and 1.54±0.17, respectively. There was no significant difference in curve slope between metastatic lymph nodes and lung cancer (t=-1.32,P>0.05); while there was significant difference between non-metastatic lymph nodes and lung cancer (t=-2.58,P<0.05). The CT spectral curve slope ratios of metastatic and non-metastatic lymph nodes to lung cancer were 0.98±0.05 and 1.40±0.12, respectively (t=-2.86,P<0.05). ROC curve showed that taking CT spectral curve slope ratio of 1.15 as cut-off value for the diagnosis of metastatic lymph nodes, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 81.1%, 87.5%, 91.5%, 73.7% and 83.5%, respectively. Dual energy CT is of value in improving the diagnostic accuracy of lymph node metastasis in NSCLC patients before treatment.

Differentiating metastatic from nonmetastatic lymph nodes in cervical cancer patients using monoexponential, biexponential, and stretched exponential diffusion-weighted MR imaging.

To determine the diagnostic value of monoexponential, biexponential and stretched exponential models for identifying lymph nodes (LNs) in patients with cervical cancer. Fifty female patients with cervical cancer underwent preoperative magnetic resonance imaging. The diffusion parameters of the LNs were calculated by fitting the values to monoexponential, biexponential and stretched exponential models and were compared between the metastatic and non-metastatic LN groups. A total of 157 LNs with high signal intensity on multi-b-value DWI were detected, 41 of which were pathologically shown to be metastatic. Metastatic LNs presented with higher pure water diffusion (D) values, lower perfusion fraction (f) values, higher diffusion heterogeneity (α) values, higher short diameter (Size-S), long diameter (Size-L) and short long diameter ratio (S/L Ratio) than non-metastatic LNs (P<0.05). The Size-S of LNs exhibited the highest diagnostic value, with an area under the curve of 0.844. Compared with the size parameters, the diffusion parameters derived from multi-b-value diffusion-weighted imaging cannot reliably discriminate metastatic from non-metastatic LNs in daily clinical routine due to limited sensitivity and specificity. • Biexponential and stretched exponential diffusion models can help to characterise LN status. • Metastatic LNs present with higher D and α values, lower f values. • Diffusion parameters were less reliable in discriminating LNs than size parameters.

Efficacy and safety of 125I seed implantation for treating neuroblastoma in nude mice

Objective To examine the efficacy and safety of 125I seed implantation for treating neuroblastoma (NB) in animal models. Methods A total of 45 nude mice models of neuroblastoma were constructed and divided into the 125I group.control group.and blank group at 15 mice per group. The long and short diameters of the tumor were measured every 3 days.and the tumor inhibition rate was calculated every 9 days. Apoptotic and proliferative protein expression levels in tumor tissue and peritumoral tissue.as well as endocrine markers and bone marrow of the nude mice.were analyzed. The independent sample t test was used to compare the mean scores.and ANOVA was used for comparison between multiple groups. Results Tumor volume inhibition rate was significantly higher in the 125I group than in the control group and blank group on days 9.18.and 27(all P 0.05). In addition.no significant difference in the expression of Caspase-3 and PCNA in peritumoral tissue was observed between the 125I group.control group.and blank group (all P>0.05). Cell apoptosis in tumor tissue was significantly lower in the blank group and control group than in the 125I group (all P 0.05). There was no significant difference in endocrine markers between the three groups (P>0.05). There was no significant bone marrow suppression in the 125I group.and this observation was similar to those in the control group and blank group (all P>0.05). Conclusions 125I seeds have significant toxicity to NB.125I seed implantation is safe in nude mice with NB within the therapeutic doses. Key words: 125I seeds; Neuroblastoma; Nude mice; Efficacy; Safety

Investigation on mechanical properties of polycrystalline W nanowire

Metal nanowires are stirring the attention of scientific world because of their many unique properties. W single crystal nanowires, with bcc crystal configuration, have become focus of many studies due to lack of complete insight of their mechanical deformation. However, polycrystalline W nanowires are not thoroughly studied yet. In this work, molecular dynamics simulation is used to identify different aspects of deformation and plasticity of polycrystalline W nanowire using EAM potential and a constant strain rate of 109s-1. Impact of grain size, diameter, and temperature on the elastic properties is analyzed. Average grain size is varied from 4.63nm to 25nm keeping the diameter constant at 5nm and temperature at 10K. Diameter of the nanowire is varied from 2 to 5nm keeping the average grain size and length to diameter ratio constant while temperature was changed from 10K to 500K maintaining fixed diameter and grain size. It is observed that inverse Hall-Petch behavior dominates the plasticity in polycrystalline nanowires and grain boundary sliding becomes the dominating mechanism of plasticity with a critical grain size. Nanowires with shorter diameter are found to be stronger and elevated temperature weakens the nanowire irrespective of the grain size.

The relations between network-operation and topological-property in a scale-free and small-world network with community structure

It is always an open, demanding and difficult task for generating available model to simulate dynamical functions and reveal inner principles from complex systems and networks. In this article, due to lots of real-life and artificial networks are built from series of simple and small groups (components), we discuss some interesting and helpful network-operation to generate more realistic network models. In view of community structure (modular topology), we present a class of sparse network models N(t,m). At the moment, we capture the fact the N(t,4) has not only scale-free feature, which means that the probability that a randomly selected vertex with degree k decays as a power-law, following P(k)∼k−γ, where γ is the degree exponent, but also small-world property, which indicates that the typical distance between two uniform randomly chosen vertices grows proportionally to logarithm of the order of N(t,4), namely, relatively shorter diameter and lower average path length, simultaneously displays higher clustering coefficient. Next, as a new topological parameter correlating to reliability, synchronization capability and diffusion properties of networks, the number of spanning trees over a network is studied in more detail, an exact analytical solution for the number of spanning trees of the N(t,4) is obtained. Based on the network-operation, part hub-vertex linking with each other will be helpful for structuring various network models and investigating the rules related with real-life networks.