Volumetric measurement techniques for assessment of cutaneous neurofibromas:A review

Cutaneous neurofibroma(cNF)is a prevalent clinical manifestation of neurofibromatosis type 1,significantly affecting the well-being and quality of life of the affected individuals.The adoption of reliable and reproducible volumetric measurement techniques is essential for precisely evaluating tumor burden and plays a critical role in the development of effective treatments for cNF.This study focuses on widely used volumetric measurement techniques,including vernier calipers,ultrasound,computed tomography,magnetic resonance imaging,and three-dimensional scanning imaging.It outlines the merits and drawbacks of each technique in assessing the cNF load,providing an overview of their current applications and ongoing research advancements in this domain.

Liver and spleen volume variations in patients with hepatic fibrosis

AIM： To study the liver and spleen volume variations in hepatic fibrosis patients at different histopathological stages. METHODS： Multidetector computed tomography （MDCT） scan was performed in 85 hepatic fibrosis patients. Liver volume （LV） and spleen volume （SV） were measured. Fifteen healthy individuals served as a control group （SO）. The patients were divided into stage 1 （S1） group （n = 34）, stage 2 （S2） group （n = 25）, stage 3 （S3） group （n = 16）, and stage 4 （S4） group （n = 10） according to their histopathological stage of liver fibrosis. RESULTS： The LV and standard LV （SLV） had a tendency to increase with the severity of fibrosis, but no statistical difference was observed in the 5 groups （LV： F = 0.245, P = 0.912; SLV： F = 1.902, P = 0.116）. The SV was gradually increased with the severity of fibrosis, and a statistically significant difference in SV was observed among the 5 groups （P 〈 0.01）. The LV/SV ratio and SLV/SV ratio were gradually decreased with the aggravation of hepatic fibrosis, and statistically significant differences in both LV/SV and SLV/SV were found among the 5 groups （P 〈 0.01）.CONCLUSION： The absence of obvious LV reduction in patients with chronic liver disease may be a morphological index of patients without liver cirrhosis. The SV is related to the severity of fibrosis, and the spleen of patients with advanced fibrosis is enlarged evidently. The LV/SV ratio and SLV/SV ratio are of a significant clinical value in the diagnosis of advanced liver fibrosis.

Everolimus halts hepatic cystogenesis in a rodent model of polycystic-liver-disease

AIM To develop a MRI-based method for accurate determination of liver volume(LV) and to explore the effect of long-term everolimus(EVR) treatment on LV in PCK rats with hepatomegaly. METHODS Thirty-one female PCK rats(model for polycystic-liverdisease: PCLD) were randomized into 3 groups and treatment was started at 16 wk, at the moment of extensive hepatomegaly(comparable to what is done in the human disease). Animals received: controls(n = 14), lanreotide(LAN: 3 mg/kg per 2 wk)(n = 10) or everolimus(EVR: 1 mg/kg per day)(n = 7). LV was measured at week 16, 24, 28. At week 28, all rats were sacrificed and liver tissue was harvested. Fibrosis was evaluated using quantitative image analysis. In addition, gene(quantitative RT-PCR) and protein expression(by Western blot) of the PI3K/Ak T/m TOR signaling pathway was investigated. RESULTS LV determination by MRI correlated excellent with the ex vivo measurements(r = 0.99, P < 0.001). The relative changes in LV at the end of treatment were:(controls) +31.8%;(LAN) +5.1% and(EVR) +8.8%, indicating a significantly halt of LV progression compared with controls(respectively, P = 0.01 and P = 0.04). Furthermore, EVR significantly reduced the amount of liver fibrosis(P = 0.004) thus might also prevent the development of portal hypertension. There was no difference in phosphorylation of Akt(Threonine 308) between LAN-treated PCK rats control PCK rats, whereas S6 was significantly more phosphorylated in the LAN group. Phosphorylation of Akt was not different between controls and EVR treated rats, however, for S6 there was significantly less phosphorylation in the EVR treated rats. Thus, both drugs interact with the PI3K/Ak T/m TOR signaling cascade but acting at different molecular levels.CONCLUSION Everolimus halts cyst growth comparable to lanreotide and reduces the development of fibrosis. m TORinhibition should be further explored in PCLD patients especially those that need immunosuppression.

Filament diameter measurement system based on dual diffraction

This Letter proposes a brand-new filament diameter measurement method based on what is called ＂dual diffraction,＂ in that a grating is added behind the filament to make full use of its subdivision and amplification characteristics. Higher measurement accuracy is achieved by this method compared with the traditional diffraction method. To verify its accuracy, three standard filaments with nominal values of 100.2, 120.1, and 140.8 μm are measured by the dual diffraction method and traditional diffraction method under the same experimental conditions. The relative measurement errors of the new method are less than 0.75%, and its average relative error is reduced by 56% compared with the traditional diffraction method.

Indication of lower neck irradiation in nasopharyngeal carcinoma without nodal metastasis： the potential impact of tumor volume

Background Elective radiation of lower neck is controversial for nasopharyngeal carcinoma （NPC） without lymph node metastasis （NO disease）. Tumor volume is an important prognostic indicator. The objective of this study is to explore the potential impact of tumor volume on the indication of the lower neck irradiation for N0-NPC, by a qualitative evaluation of the relationship between tumor volume and nodal metastasis. Methods Magnetic resonance （MR） images of 99 consecutive patients with NPC who underwent treatment were retrospectively reviewed. Primary tumor volumes of NPC were semi-automatically measured, nodal metastases were N-classified and neck level involvements were examined. Distributions of tumor volumes among N-category-based groups and distributions of N-categories among tumor volume-based groups were analyzed, respectively. Results The numbers of patients with NO to N3 disease were 12, 39, 32, and 16, respectively. The volumes of primary tumor were from 3.3 to 89.6 ml, with a median of 17.1 ml. For patients with nodal metastasis, tumor volume did not increase significantly with the advancing of N-category （P 〉0.05）. No significant difference was found for the distribution of N1, N2, and N3 categories among tumor volume-based groups （P 〉0.05）. Nevertheless patients with nodal metastasis had significantly larger tumor volumes than those without metastasis （P 〈0.05）. Patients with larger tumor volumes were associated with an increased incidence of nodal metastasis. Conclusions Certain positive correlations existed between tumor volume and the presence of nodal metastasis. The tumor volume （〉10 ml） is a potential indicator for the lower neck irradiation for N0-NPC.

Calculation of Strain Amplification Matrix for Strain Invariant Failure Theory Based on Representative Volume Element Models with Periodical Boundary Condition

Strain invariant failure theory (SIFT) is a micro-mechanics-based failure theory for multi-scale failure analysis of composite materials originally proposed by Gosse and Christensen. In this paper, the approach for obtaining strain amplification matrix which is a key step for the execution of SIFT is improved by adopting representative volume element (RVE) finite element models considering periodical boundary condition, based on which more actual deformation mode is reflected. The deformation modes and strain data at the characteristic points of the centroid cell of multi-cell RVE model are analyzed and taken as a reference. It can be concluded that more reasonable deformation mode and relationship between the micro-mechanical and macro-mechanical strain states are obtained by employing the new model. Finally, numerical examples are provided to illustrate the determination of strain amplification factors within the RVEs considering periodical boundary condition at the characteristic points. © 2017, Shanghai Jiaotong University and Springer-Verlag GmbH Germany.

Predicting Infiltrative Hepatocellular Carcinoma Patient Outcome Post-TACE:MR Bias Field Correction Effect on 3D-quantitative Image Analysis

Background and Aims:To investigate the impact of MR bias field correction on response determination and survival prediction using volumetric tumor enhancement analysis in patients with infiltrative hepatocellular carcinoma,after transcatheter arterial chemoembolization(TACE).Methods:This study included 101 patients treated with conventional or drug-eluting beads TACE between the years of 2001 and 2013.Semi-automated 3D quantification software was used to segment and calculate the enhancing tumor volume(ETV)of the liver with and without bias-field correction on multi-phasic contrast-enhanced MRI before and 1-month after initial TACE.ETV(expressed as cm3)at baseline imaging and the relative change in ETV(as%change,ETV%)before and after TACE were used to predict response and survival,respectively.Statistical survival analyses included Kaplan-Meier curve generation and Cox proportional hazards modeling.Q statistics were calculated and used to identify the best cut-off value for ETV to separate responders and non-responders(ETV cm3).The difference in survival was evaluated between responders and non-responders using Kaplan-Meier and Cox models.Results:MR bias field correction correlated with improved response calculation from baseline MR as well as survival after TACE;using a 415 cm3 cut-off for ETV at baseline(hazard ratio:2.00,95%confidence interval:1.23-3.26,p=0.01)resulted in significantly improved response prediction(median survival in patients with baseline ETV<415 cm3:19.66 months vs.≥415 cm3:9.21 months,p<0.001,log-rank test).A≥41%relative decrease in ETV(hazard ratio:0.58,95%confidence interval:0.37-0.93,p=0.02)was significant in predicting survival(ETV≥41%:19.20 months vs.ETV<41%:8.71 months,p=0.008,log-rank test).Without MR bias field correction,response from baseline ETV could be predicted but survival after TACE could not.Conclusions:MR bias field correction improves both response assessment and accuracy of survival prediction using whole liver tumor enhancement analysis from baseline MR after initial TACE in patients with infiltrative hepatocellular carcinoma.

Applications of active acoustics in particle technology

Earlier work by the authors in which active sound pressure signals and impulsive pressure disturbances were used to measure flow rates in gas solid systems was briefly reviewed. Work in progress with an emerging technology in which Helmholtz resonance is applied to the measurement of volume is outlined.

Method for C/N ratio estimation using Mask R-CNN and a depth camera for organic fraction of municipal solid wastes

Fast assessment of the initial carbon to nitrogen ratio(C/N)of organic fraction of municipal solid waste(OFMSW)is an important prerequisite for automatic composting control to improve efficiency and stability of the bioconversion process.In this study,a novel approach was proposed to estimate the C/N of OFMSW,where an instance segmentation model was applied to predict the masks for the waste images.Then,by combining the instance segmentation model with the depth-camera-based volume calculation algorithm,the volumes occupied by each type of waste were obtained,therefore the C/N could be estimated based on the properties of each type of waste.First,an instance segmentation dataset including three common classes of OFMSW was built to train mask region-based convolutional neural networks(Mask R-CNN)model.Second,a volume measurement algorithm was proposed,where the measurement result of the object was derived by accumulating the volumes of small rectangular cuboids whose bottom area was calculated with the projection property.Then the calculated volume was corrected with linear regression models.The results showed that the trained instance segmentation model performed well with average precision scores AP_(50)=82.9,AP_(75)=72.5,and mask intersection over unit(Mask IoU)=45.1.A high correlation was found between the estimated C/N and the ground truth with a coefficient of determination R2=0.97 and root mean square error RMSE=0.10.The relative average error was 0.42%and the maximum error was only 1.71%,which indicated this approach has potential for practical applications.