A Novel Multi-Layer Poro-Elastic Model of Lung Deformation

2011 ◽  
Author(s):  
Zhiliang Li ◽  
Xiang Long ◽  
Olusegun J. Ilegbusi
Keyword(s):  
Ct Scan ◽  
Lung Tumor ◽  
Human Subjects ◽  
Cancer Center ◽  
Elastic Model ◽  
Interaction Technique ◽  
Model Flow ◽  
Novel Method ◽  
Lung Deformation ◽  
Lung Lobes

This paper presents a novel method to simulate flow and deformation of the lung. The lung is assumed to behave as a poro-elastic medium with heterogeneous elastic property. The method uses a flow-structure interaction technique to simultaneously model flow within the airway and deformation of the lung lobes. The 3D lung geometry is reproduced from 4D CT scan dataset obtained on real human subjects at a Cancer Center. The non-linear Young’s modulus is estimated in a parallel study based on similar CT scan dataset. The novelty of the present technique lies in the use of onion-layer grid with distributed spatial permeability. It allows prediction of the spatial lung displacement that could be used for tracking lung tumor during radiotherapy.

scholarly journals Modeling Airflow Using Subject-Specific 4DCT-Based Deformable Volumetric Lung Models

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Olusegun J. Ilegbusi ◽  
Zhiliang Li ◽  
Behnaz Seyfi ◽  
Yugang Min ◽  
Sanford Meeks ◽  
...  
Keyword(s):  
Lung Tumor ◽  
Tumor Motion ◽  
Tissue Elasticity ◽  
Interaction Technique ◽  
Subject Specific ◽  
Regional Lung ◽  
Computational Fluid Dynamics Cfd ◽  
Specific Tissue ◽  
Lung Radiotherapy ◽  
Lung Deformation

Lung radiotherapy is greatly benefitted when the tumor motion caused by breathing can be modeled. The aim of this paper is to present the importance of using anisotropic and subject-specific tissue elasticity for simulating the airflow inside the lungs. A computational-fluid-dynamics (CFD) based approach is presented to simulate airflow inside a subject-specific deformable lung for modeling lung tumor motion and the motion of the surrounding tissues during radiotherapy. A flow-structure interaction technique is employed that simultaneously models airflow and lung deformation. The lung is modeled as a poroelastic medium with subject-specific anisotropic poroelastic properties on a geometry, which was reconstructed from four-dimensional computed tomography (4DCT) scan datasets of humans with lung cancer. The results include the 3D anisotropic lung deformation for known airflow pattern inside the lungs. The effects of anisotropy are also presented on both the spatiotemporal volumetric lung displacement and the regional lung hysteresis.

Cancer surgery during the COVID‐19 pandemic: The experience of a comprehensive cancer center performing preoperative screening by RT‐PCR and chest CT scan

2021 ◽  
Vol 123 (4) ◽  
pp. 815-822
Author(s):  
Joanne Guerlain ◽  
Fabienne Haroun ◽  
Alexandra Voicu ◽  
Charles Honoré ◽  
Franck Griscelli ◽  
...  
Keyword(s):  
Ct Scan ◽  
Chest Ct ◽  
Cancer Surgery ◽  
Comprehensive Cancer Center ◽  
Cancer Center ◽  
Preoperative Screening ◽  
Rt Pcr ◽  
Chest Ct Scan

scholarly journals Implementation of PD-L1 22C3 IHC pharmDxTM in Cell Block Preparations of Lung Cancer: Concordance with Surgical Resections and Technical Validation of CytoLyt® Prefixation

2020 ◽  
Vol 64 (6) ◽  
pp. 577-587
Author(s):  
Si Kei Lou ◽  
Hyang Mi Ko ◽  
Tomonari Kinoshita ◽  
Scott MacDonald ◽  
Jessica Weiss ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Predictive Value ◽  
Interim Analysis ◽  
Lung Tumor ◽  
Intraclass Correlation ◽  
Cancer Center ◽  
Anatomical Site ◽  
Good Reliability ◽  
Surgical Specimen ◽  
Technical Validation

<b><i>Background:</i></b> Programmed death ligand-1 (PD-L1) assessed by immunohistochemistry (IHC) is used as biomarker for pembrolizumab therapy in advanced stage lung cancer patients. However, data permitting direct performance comparison between cytology and surgical specimen types are limited since both specimens from a single tumor site are infrequently available. In addition, alcohol fixation used with cytology specimens requires technical validation of the PD-L1 IHC assay before clinical use. We here report our experience with implementation of the PD-L1 22C3 IHC pharmDx<sup>TM</sup> assay for cytologic samples at a large tertiary cancer center. <b><i>Study Design:</i></b> Archival formalin-fixed (FF), paraffin-embedded cell blocks (CBs) and subsequent lung tumor resections (LTRs) from the same anatomical site were used for a direct comparison of PD-L1 tumor proportion scores (TPSs). TPS values were independently determined by one surgical lung pathologist and two cytopathologists blinded to the specimen pairs. An interim analysis was performed to facilitate the pooling of expertise among observers. After PD-L1 22C3 IHC pharmDx<sup>TM</sup> implementation for FF cytology specimens, dual-processed samples were used for a prospective technical validation of CytoLyt® prefixation (CF). Digital image analysis was performed for a subset of dual-processed specimens. <b><i>Results:</i></b> Eighty-one CBs and LTRs were included for comparison of the specimen types. PD-L1 assessment in CBs had an accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 88.9/72.8, 66.7/73.5, 95.2/72.3, 80.0/65.8, and 90.9/79.1% for the ≥50/≥1% cutoff, respectively. The intraclass correlation coefficient was 0.84 (95% confidence interval [CI]: 0.76, 0.90), and it improved after interim analysis (before: 0.79 and after: 0.92). The overall concordance between CF and FF for the categories defined by the ≥50/≥1% cutoff values was 90.4% (95% CI: 79.0, 96.8). Similar assay performance was confirmed by digital analysis. <b><i>Conclusions:</i></b> PD-L1 22C3 IHC pharmDx<sup>TM</sup> shows good reliability if used with CB preparations. CF does not impact assay results significantly. Clinical validation with outcome data is needed, and digital methods of assessment should be further investigated.

Tactile Eye Pressure Measurement Through the Eyelid

2015 ◽  
Author(s):  
Eniko T. Enikov ◽  
Péter P. Polyvás ◽  
Gholam Peyman ◽  
Sean Mccafferty
Keyword(s):  
Intraocular Pressure ◽  
Human Subjects ◽  
Statistical Error ◽  
Applanation Tonometry ◽  
Tactile Sensors ◽  
Non Invasive ◽  
Digital Palpation ◽  
Early Results ◽  
Novel Method ◽  
Eye Pressure

This article presents the early results from a 10-person human subject study evaluating the accuracy of a novel method of indirect estimation of intraocular pressure using tactile sensors. Manual digital palpation tonometery is an old method used to estimate the eye pressure through palpation with ones fingers. Based on this concept, we present an instrumented measurement method, where multiple tactile stiffness sensors are used to infer the intraocular pressure of the eye. The method is validated using experimental data gathered from human subjects with eye pressures from 15 to 22 mmHg and determined by Goldman applanation tonometry (GAT). Bland-Altman plots comparing the GAT measurements and the proposed through-the-eye-lid tonometry indicate a statistical error of 5.16 mmHg, within the 95% confidence interval, which compares favorably with the FDA-mandated error bound of 5 mmHg. Details on the unit operation and data filtering are also presented. Due to its indirect and non-invasive nature, the proposed new tactile tonometry method can be applied at home as a self-administered home tonometer for management of glaucoma.

SUV max of the most intense lesion on fdgpet/CT scan at baseline as a potential prognostic factor in stage IV (NSCLC): A retrospective review.

2013 ◽  
Vol 31 (15_suppl) ◽  
pp. e19070-e19070
Author(s):  
Manga Devi Kodali ◽  
Amol Takalkar ◽  
Runhua Shi ◽  
Prakash Peddi ◽  
Glenn Morris Mills ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Ct Scan ◽  
Retrospective Review ◽  
Lung Tumor ◽  
Performance Status ◽  
Prognostic Significance ◽  
Stage Iv ◽  
Tumor Doubling Time ◽  
Pet Ct ◽  
Primary Lung Tumor

e19070 Background: Lung cancer is the leading cause of mortality in United States and worldwide. Stage IV lung cancer has poor prognosis with 5-year survival of 2%. Limited numbers of factors are known to predict survival in stage IV NSCLC (Non Small Cell Lung Cancer) including stage at diagnosis, Performance Status (PS), genomic expression profile. Earlier studies have found SUV max (Maximum Standardized Uptake Value) of primary lung tumor on FDGPET/CT (Fluoro Deoxy Glucose –Positron Emission Tomography/Computed Tomography) correlates with tumor doubling time and survival. However prior studies included stage I-IV NSCLC patients and SUVmax of primary lung tumor. Hence we performed this study with only clinical stage IVNSCLC who underwent FDGPET/CT scan at baseline to determine whether SUVmax value of most intense lesion has any prognostic significance. Methods: Retrospective review identified 46 patients (September 2004- September 2011) that were diagnosed with stage IV NSCLC at our institution. SUVmax of most intense lesion on FDG PET/CT scan was determined utilizing an automated program on a dedicated PET/CT workstation by a single nuclear medicine specialist. Cox regression analysis and Log-rank test were used to analyze data. Results: Descriptive statistics: Median age 61.6 (43.8-77.8), Females 17 (36%), African Americans 26 (56%), Performance status 0-1=36 (80%), number of metastatic sites 1-2=30 (65%), Adenocarcinoma 32 (70%), Chemotherapy 31 (61%), SUV max- primary (65%), other sites (35%). The patient population was subdivided into two groups using the median SUVmax of 17.8. The median survival of patients having SUV max ≤17.8 and SUVmax > 17.8 was 13.4 months and 4.5 months respectively (P =0.0269). Multivariate analysis indicated PS (HR=2.8), any chemotherapy (HR=2.56) and SUV max ≤ 17.8 (HR=1.98, P=0.04) predicted survival. Conclusions: SUV max of the most intense lesion at the time of presentation predicts worse outcome in stage IVNSCLC and needs to be validated in a prospective study. PETCT may be able to predict the areas that harbor resistant clones of cells, described in previous studies as tumor heterogeneity, which may confer prognostic significance.

scholarly journals Chest CT Imaging Characteristics of COVID-19 Pneumonia in Surviving and Non-Surviving Hospitalized Patients: A Retrospective Study in a Referral Center in Tehran, Iran

2021 ◽  
Vol 18 (2) ◽  
Author(s):  
Sara Besharat ◽  
Fatemehsadat Rahimi ◽  
Siamak Afaghi ◽  
Farzad Esmaeili Tarki ◽  
Fatemeh Pourmotahari ◽  
...  
Keyword(s):  
Pleural Effusion ◽  
Ct Scan ◽  
Chest Ct ◽  
Ct Scans ◽  
Early Management ◽  
Ct Findings ◽  
Imaging Characteristics ◽  
Significant Difference ◽  
Chest Ct Scan ◽  
Lung Lobes

Background: Coronavirus disease 2019 (COVID-19) has several chest computed tomography (CT) characteristics, which are important for the early management of this disease, because viral detection via RT-PCR can be time-consuming, resulting in a delayed pneumonia diagnosis. The Radiological Society of North America (RSNA) proposed a reporting language for CT findings related to COVID-19 and defined four CT categories: typical, indeterminate, atypical, and negative. Objectives: To retrospectively evaluate the chest CT characteristics of patients with COVID-19 pneumonia. Patients and Methods: A total of 115 hospitalized laboratory-verified COVID-19 cases, underdoing chest CT scan, were included in this study from April 30 to May 15, 2020. Of 115 cases, 53 were discharged from the hospital, and 62 expired. The initial clinical features and chest CT scans were assessed for the type, pattern, distribution, and frequency of lesions. Moreover, the findings were compared between ward-hospitalized, ICU-admitted, and non-surviving (expired) patients. Results: Of four CT categories, typical CT findings for COVID-19 were more frequent in the expired group (77.4%), compared to the ward-admitted (44.8%) and ICU-admitted (70.8%) groups (P = 0.017). However, no significant difference was observed in the prevalence of intermediate or atypical CT findings between the groups. Negative CT scans for the diagnosis of COVID-19 were significantly fewer in the expired group (0%) as compared to the ward-admitted (10.3%) and ICU-admitted (8.3%) groups (P = 0.0180). Also, the mean number of involved lung lobes and segments was significantly higher in the expired group compared to the other two groups (P = 0.032 and 0.010, respectively). The right upper lobe involvement, right middle lobe involvement, bilateral involvement, central lesion, air bronchogram, and pleural effusion were among CT scan findings with a significantly higher prevalence in non-surviving cases (P < 0.0001, 0.047, 0.01, 0.036, 0.038, and 0.047, respectively). Conclusion: The increased number of involved lung lobes and segments, bilateral and central distribution patterns, air bronchogram, and severe pleural effusion in the initial chest CT scan can be related to the increased severity and poor prognosis of COVID-19.

scholarly journals Staging Laparoscopy Is Still a Valuable Tool for Optimal Gastric Cancer Management

2021 ◽  
Author(s):  
Erica Sakamoto ◽  
Marcus Fernando Kodama Pertille Ramos ◽  
Marina Alessandra Pereira ◽  
Andre Roncon Dias ◽  
Ulysses Ribeiro Junior ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Ct Scan ◽  
Imaging Techniques ◽  
Clinicopathological Characteristics ◽  
Staging Laparoscopy ◽  
Preoperative Imaging ◽  
Cancer Center ◽  
Cancer Management ◽  
Stage Ivb ◽  
Sensitivity Specificity

Abstract Purpose: Complete surgical resection is the main determining factor in the survival of advanced gastric cancer (AGC) patients, but resection should be avoided in metastatic disease. Peritoneum is a common site of metastasis and preoperative imaging techniques still fail to detect peritoneal metastasis (PM). Thus, the aim of this study was to evaluate the role of Staging Laparoscopy (SL) in the staging of AGC patients in a Western tertiary cancer center. Methods: We reviewed 130 patients with gastric adenocarcinoma submitted to SL from 2009 to 2020 from a prospective database. Clinicopathological characteristics were analyzed to identify factors associated with the presence of PM. We also evaluated the accuracy and strength of agreement between computed tomography (CT) and SL in detecting PM, and the change in treatment strategy after SL. Results: Among the 130 patients, PM was identified in 66 patients (50.76%) - P1 group. The sensitivity, specificity and accuracy of CT in detecting PM were 51,5%, 87,5% and 69.2%, respectively. According to the Kappa coefficient, concordance between SL and CT was 38.8%. In multivariate analysis, ascites (p=0.001) and suspected PM on CT scan (p=0.007) were statistically correlated with the P1 group. In 40 patients (30.8%), staging and treatment plans changed after SL (32 patients avoided unnecessary laparotomy and 8 patients who were previously considered stage IVb by CT scan were referred for surgical treatment). Conclusions: Even with current advances in imaging techniques, SL demonstrated an important role in the diagnosis of PM and remains valuable for determining the correct therapeutic strategy.

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