Turbinate atrophy evaluation in pigs by computed tomography

2003 ◽  
Vol 51 (4) ◽  
pp. 485-491 ◽  
Author(s):  
T. Magyar ◽  
F. Kovács ◽  
T. Donkó ◽  
H. Bíró ◽  
R. Romvári ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Nasal Cavity ◽  
Scoring System ◽  
Ct Images ◽  
Area Ratio ◽  
Ct Scans ◽  
Non Invasive ◽  
Visual Scoring ◽  
Ratio Determination ◽  
Visualisation Technique

Computed tomography (CT), a non-invasive visualisation technique was applied for imaging the bony structures of the nasal cavity of pigs, and compared to the traditional scoring system of turbinate atrophy in swine. Twenty-three 27-week-old pigs representing various stages of turbinate atrophy were used. Nasal structures were visually scored on CT scans and transversal cuts of the noses at the level of the first upper premolar teeth using the same scoring system in both cases. A tissue/air area ratio was also determined based on density differences. A highly significant correlation was found between visual scoring of CT images and transversal cuts of pig noses (r = 0.98, p < 0.0001) as well as between visual scoring of CT images and tissue/air area ratio determination (r = -0.82, p < 0.0001).

scholarly journals A Method for Tooth Model Reconstruction Based on Integration of Multimodal Images

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Xinwen Zhou ◽  
Yangzhou Gan ◽  
Jing Xiong ◽  
Dongxia Zhang ◽  
Qunfei Zhao ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Orthodontic Treatment ◽  
Ct Images ◽  
Ct Scans ◽  
Reconstruction Method ◽  
Model Reconstruction ◽  
Crown Area ◽  
Computer Aided ◽  
Multimodal Images ◽  
Reconstructed Model

A complete digital tooth model is needed for computer-aided orthodontic treatment. However, current methods mainly use computed tomography (CT) images to reconstruct the tooth model which may require multiple CT scans during orthodontic progress, and the reconstructed model is also inaccurate in crown area. This study developed a tooth model reconstruction method based on integration of CT images and laser scan images to overcome these disadvantages. In the method, crown models and complete tooth models are first reconstructed, respectively, from laser scan images and CT images. Then, crown models from laser scan images and tooth models from CT images are registered. Finally, the crown from laser scan images and root from CT images were fused to obtain a new tooth model. Experimental results verified that the developed method is effective to generate the complete tooth model by integrating CT images and laser scan images. Using the proposed method, the reconstructed models provide more accurate crown than CT images, and it is feasible to obtain complete tooth models at any stage of orthodontic treatment by using one CT scan at the pretreatment stage and one laser scan at that stage to avoid multiple CT scans.

scholarly journals Gender differences in the maxillary sinus volume : a study using computed tomography scans of a sample of Tamil Nadu population

2016 ◽  
Vol 05 (03) ◽  
pp. 138-142
Author(s):  
N Muthukumaravel ◽  
K. Y. Manjunath
Keyword(s):  
Computed Tomography ◽  
Maxillary Sinus ◽  
Tamil Nadu ◽  
Ct Images ◽  
Ct Scans ◽  
P Value ◽  
Gender Determination ◽  
Maxillary Sinus Volume ◽  
Significant Difference ◽  
Maxillary Sinuses

Abstract Background and aims : Measurements of the maxillary sinus volumes in computed tomography (CT) scans can be used for determination of gender when other methods are inconclusive. Maxillary sinus dimension measurements are valuable in studying sexual dimorphism and can assist in gender determination. The radiographic images can provide adequate measurements for maxillary sinuses that cannot be approached by other means. The purpose of the present study was to determine and compare the volume of the maxillary sinus between males and females of Tamil Nadu region using CT scans. Materials and methods : This study was carried out by using CT images of head region of 100 males and 100 females who underwent CT scanning for indications other than the pathology of the maxillary sinuses. The CT images obtained were of patients between 20 to 50 years of age. The maxillary sinus volume of each side were calculated by using the following formula: Maximal width X Maximal height X Maximal depth X 0.5. Comparison of data between genders and sides was done. The statistical inference was derived by applying unpaired student "t" test and the p value was obtained (p value <.05 was considered statistical significant). Results: Oncomparison of males with females, the mean volumes of maxillary sinuses on each side (left and right) had shown a statistically significant difference (p<.OOOl ). The maxillary sinus volumes of the males were found to be significantly higher than that of the females. Among males, the average mean volume of maxillary sinuses (right + left) is 15.15 ± 0.45 cm3. Among females, the average mean volume of maxillary sinuses (right + left) is 12.77 ± 1.34 em' which is significantly lesser than that of the males. Conclusion : It can be concluded that the volumes of the maxillary sinuses of males are larger than those of the females and this difference is statistically significant. Maxillary sinus dimension measurements can assist in gender determination.

Not All Positive Interim PET/CT Scans Are Reliably Predictive for Progression Free Survival in Hodgkin Lymphoma (HL) Patients. A Proposed Model for a Functional Scoring Scale.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1452-1452
Author(s):  
Eldad J. Dann ◽  
Ada Tamir ◽  
Ron Epelbaum ◽  
Irit Avivi ◽  
Menachem Ben-Shachar ◽  
...  
Keyword(s):  
Scoring System ◽  
Progression Free Survival ◽  
Scoring Systems ◽  
Ct Scans ◽  
Free Survival ◽  
Residual Mass ◽  
Fdg Uptake ◽  
Interim Pet ◽  
Visual Scoring ◽  
Pet Ct

Abstract Interim PET-CT is used to predict the progression-free survival in HL (Gallamini, JCO 2007). However, what constitutes a functionally positive interim PET-CT has not been established. Does a single focus of reduced residual uptake predict and justify an escalation of therapy? In this study, 96 patients [47 females, 49 males; median age 30 (17–57) years] with HL (stage I -3, II- 50, III-18, IV-25), treated at the Rambam Medical Center (Haifa, Israel) since 2001 were evaluated. Prior to the interim PET, patients received 2 cycles of ABVD (33) or BEACOPP (41) or escalated BEACOPP (EB) (22). While an interim PET-CT was performed on all patients, only patients receiving BEACOPP had a planned escalation or reduction of therapy (for the escalated BEACOPP group) following the interim PET-CT as part of the protocol. The 4-year progression-free survival (PFS) and overall survival (OS) of 96 HL patients were better for negative interim PET-CT (93% and 98%) than for positive studies. The analysis for predictive PFS, by PET-CT is based on a static binary score which defines response depending on the presence or absence of any abnormal uptake on interim study. Thus, 24 patients had a positive interim PET-CT, in 11 of whom, the therapy was escalated and 3 had continued therapy with EB. Three patients in the escalated group and two who were not escalated progressed. Nineteen of the 24 patients with a positive interim PET responded fully. However, not all positive PET-CT scans were the same; there was a difference in the number of residual sites and intensity, which led us to propose the following functional model as outlined in Table 1. Table 1. Dynamic Scoring of PET-CT for Interim Analysis of HL Score # of residual foci: compared with baseline Intensity of uptake 0 0 0 1 1 reduced 2 &gt;1 but less than baseline reduced 3 unchanged reduced 4 unchanged or increased number same or increased This model was compared with the scoring system suggested by the Consensus of the Imaging Subcommittee (Juweid, JCO 2007) where any residual mass &lt; 2cm with an abnormal FDG uptake, a residual mass ≥ 2 cm, or an abnormal FDG uptake moderately increased above that of the mediastinum are considered positive. In the proposed dynamic model, patients with an interim PET-CT score of 0–2 are functionally similar; a PET-CT with a positive predictive value would only be a score of 3 or greater. The results of using this model for all the 96 patients are presented in Table 2. Of note, the specificity of the current model was significantly better than in both static scoring systems (p = 0.0001). Table 2. Comparison of PET-CT Performance by 3 Scoring Systems Performance Static visual assessment % (n) Scoring system: Consensus Imaging Subcommittee % (n) Visual dynamic score: current study % (n) PPV 21% (5/24) 19% (4/21) 50% (3/6) NPV 94% (68/72) 93% (70/75) 93% (84/90) Sensitivity 55% (5/9) 44% (4/9) 33% (3/9) Specificity 78% (68/87) 80% (70/87) 96% (84/87) In conclusion: Interim PET-CT is a useful tool for predicting prognosis in patients with HL. A dynamic visual scoring method, which reflects the functional dynamics of response in comparison to pre-treatment findings, may be a better indicator of resistant disease than static visual scoring systems. Based on the model proposed, a score of ≥3 should be considered as a cutoff point. Such a model needs to be prospectively validated in larger clinical trials.

scholarly journals Airflow Simulation inside the Nasal Cavity

2020 ◽  
Vol 4 (1) ◽  
pp. 21-25
Author(s):  
Milad Ahmadi ◽  
Mohammad Zuber ◽  
S.M. Abdul Khader
Keyword(s):  
Computed Tomography ◽  
Laminar Flow ◽  
Nasal Cavity ◽  
Ct Scans ◽  
Comsol Multiphysics ◽  
Particulate Matters ◽  
Flow Rates ◽  
Healthy Female ◽  
The Individual ◽  
Human Nose

Filtration of particulate matters in the human nose depends on the Individual aspects of the nasal cavity such as the geometry and flow rate collectively. To better understand the physiology of the nose, a 3D computational model of a human nasal cavity was developed based on the computed tomography (CT) scans of a healthy female. COMSOL Multiphysics was used to analyze the velocity patterns for laminar flow rates of 7.5L/min and 15L/min and the differences were explored and analyzed.

scholarly journals Optimization of a protocol for contrast-enhanced four-dimensional computed tomography imaging of thoracic tumors using minimal contrast agent

2021 ◽  
Author(s):  
Hongya Dai ◽  
Dingqiang Yang ◽  
Lu Chen ◽  
Yibing Zhou ◽  
Xiaojing Wen ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Contrast Agent ◽  
Flow Rate ◽  
Delay Time ◽  
Ct Images ◽  
Ct Scans ◽  
Target Delineation ◽  
4D Ct ◽  
Contrast Enhanced ◽  
Minimal Contrast

Abstract Purpose The accuracy of target delineation for node-positive thoracic tumors is dependent on both four-dimensional computed tomography (4D-CT) and contrast-enhanced three-dimensional (3D)-CT images; these scans enable the motion visualization of tumors and delineate the nodal areas. Combining the two techniques would be more effective; however, currently, there is no standard protocol for the contrast media injection parameters for contrast-enhanced 4D-CT (CE-4D-CT) scans because of its long scan durations and complexity. Thus, we aimed to perform quantitative and qualitative assessments of the image quality of single contrast-enhanced 4D-CT scans to simplify this process and improve the accuracy of target delineation in order to replace the standard clinical modality involved in administering radiotherapy for thoracic tumors. Methods Ninety consecutive patients with thoracic tumors were randomly and parallelly assigned to one of nine subgroups subjected to CE-4D-CT scans with the administration of contrast agent volume equal to the patient’s weight but different flow rate and scan delay time (protocol A1: flow rate of 2.0 ml/s, delay time of 15 s; A2: 2.0 ml/s, 20 s; A3: 2.0 ml/s, 25 s; B1: 2.5 ml/s, 15 s; B2: 2.5 ml/s, 20 s; B3: 2.5 ml/s, 25 s; C1: 3.0 ml/s, 15 s; C2: 3.0 ml/s, 20 s; C3: 3.0 ml/s, 25 s). The Hounsfield unit (HU) values of the thoracic aorta, pulmonary artery stem, pulmonary veins, carotid artery, and jugular vein were acquired for each protocol. Both quantitative and qualitative image analysis and delineation acceptability were assessed. Results The results revealed significant differences among the nine protocols. Enhancement of the vascular structures in mediastinal and perihilar regions was more effective with protocol A1 or A2; however, when interested in the region of superior mediastinum and supraclavicular fossa, protocol C2 or C3 is recommended. Conclusion Qualitatively acceptable enhancement on contrast-enhanced 4D-CT images of thoracic tumors can be obtained by varying the flow rate and delay time when minimal contrast agent is used.

Quantitative Analysis of the Transcondylar Approach to the Foramen Magnum

Neurosurgery ◽  
2001 ◽  
Vol 49 (4) ◽  
pp. 934-943 ◽  
Author(s):  
John E. Wanebo ◽  
Michael R. Chicoine
Keyword(s):  
Computed Tomography ◽  
Quantitative Analysis ◽  
Ct Images ◽  
Foramen Magnum ◽  
Ct Scans ◽  
Computed Tomographic ◽  
Suboccipital Craniotomy ◽  
Before And After ◽  
Skull Measurements ◽  
C 50

Abstract OBJECTIVE Condylar resection with suboccipital craniotomy increases foramen magnum exposure, but guidelines for when this is necessary are not defined. Cadaveric and computed tomography evaluations were completed to guide decision-making regarding the use and extent of condylar resection. METHODS Quantitative analysis of foramen magnum surgical exposures was performed on 32 skulls (64 sides) and 6 cadaveric dissections (12 sides). Computed tomographic (CT) scans were performed on cadaveric heads before and after condylar resections. Digitized images of dry skulls and CT images of cadaver heads were quantitatively analyzed. Predissection CT measurements of cadaveric heads guided extent of condylar resections, and resection accuracy was assessed with postdissection CT scans. RESULTS Skull measurements (means in parentheses) included the foramen magnum area (7.8 cm2), length (3.6 cm), width (3.1 cm), anteroposterior condylar length (2.3 cm), and axial condylar length (2.5 cm). Mean widths of potential surgical exposures for skulls were obtained for A) suboccipital craniotomy (2.3 cm), B) with 25% (2.6 cm), and C) 50% condylar resection (3.0 cm). Mean angles of exposure were as follows: A, 38.4 degrees; B, 49.1 degrees; and C, 54.3 degrees. CT scans of cadaveric heads before and after dissections yielded measurements of exposure equivalent to measurements found on the dry skulls. CONCLUSION On average, lateral exposure increases by 3 mm (13%) and 7 mm (30%) for 25 and 50% condylar resection, respectively, compared with suboccipital craniotomy alone. Angles of exposure increase by 10.7 degrees (28%) and 15.9 degrees (41%). Measurements of CT images can be used preoperatively to help analyze the need for condylar resection and intraoperatively to guide the extent of condylar resection.

scholarly journals Predicting EGFR mutation status in lung adenocarcinoma on computed tomography image using deep learning

2019 ◽  
Vol 53 (3) ◽  
pp. 1800986 ◽  
Author(s):  
Shuo Wang ◽  
Jingyun Shi ◽  
Zhaoxiang Ye ◽  
Di Dong ◽  
Dongdong Yu ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Deep Learning ◽  
Lung Adenocarcinoma ◽  
Egfr Mutation ◽  
Treatment Guidelines ◽  
Learning Model ◽  
Ct Images ◽  
Mutation Status ◽  
Non Invasive ◽  
Deep Learning Model

Epidermal growth factor receptor (EGFR) genotyping is critical for treatment guidelines such as the use of tyrosine kinase inhibitors in lung adenocarcinoma. Conventional identification of EGFR genotype requires biopsy and sequence testing which is invasive and may suffer from the difficulty of accessing tissue samples. Here, we propose a deep learning model to predict EGFR mutation status in lung adenocarcinoma using non-invasive computed tomography (CT).We retrospectively collected data from 844 lung adenocarcinoma patients with pre-operative CT images, EGFR mutation and clinical information from two hospitals. An end-to-end deep learning model was proposed to predict the EGFR mutation status by CT scanning.By training in 14 926 CT images, the deep learning model achieved encouraging predictive performance in both the primary cohort (n=603; AUC 0.85, 95% CI 0.83–0.88) and the independent validation cohort (n=241; AUC 0.81, 95% CI 0.79–0.83), which showed significant improvement over previous studies using hand-crafted CT features or clinical characteristics (p<0.001). The deep learning score demonstrated significant differences in EGFR-mutant and EGFR-wild type tumours (p<0.001).Since CT is routinely used in lung cancer diagnosis, the deep learning model provides a non-invasive and easy-to-use method for EGFR mutation status prediction.

DEVELOPMENT OF A SPECIALISED TAPE MEASURE TO ESTIMATE THE SIZE-SPECIFIC DOSE ESTIMATE

2020 ◽  
Vol 191 (3) ◽  
pp. 369-375
Author(s):  
Tomokazu Shohji ◽  
Kazuki Kuriyama ◽  
Nobutaka Yanano ◽  
Yo Katoh
Keyword(s):  
Computed Tomography ◽  
Radiation Dose ◽  
Radiation Exposure ◽  
Ct Images ◽  
Ct Scans ◽  
Dose Estimate ◽  
Ct Examination ◽  
Tape Measure ◽  
Wide Range ◽  
Standard Deviations

Abstract The risk in computed tomography (CT) examinations is radiation exposure. We aimed to develop a specialised tape measure for determining the size-specific dose estimate (SSDE) for patients undergoing CT scans. The scanning parameters used were those of the abdominal protocol in our institute. With this method, the SSDE220 and standard deviations obtained from CT images for the liver, pelvic and lung areas, corresponded closely to the SSDEtape and standard deviations obtained using the tape measure. We thus devised a new idea that allows the estimation of the SSDE220 using a specialised tape measure before the CT examination, allowing for an informed explanation of the radiation dose to the patient. Although the tape measure developed in this study is specific to one particular CT instrument, the method could be adapted to a wide range of radiography applications.

scholarly journals Tailoring steroids in the treatment of COVID-19 pneumonia assisted by CT scans: three case reports

2020 ◽  
Vol 28 (5) ◽  
pp. 885-892 ◽  
Author(s):  
Ying Su ◽  
Yi Han ◽  
Jie Liu ◽  
Yue Qiu ◽  
Qian Tan ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Computed Tomography ◽  
Quantitative Analysis ◽  
Disease Severity ◽  
Initial Treatment ◽  
Case Reports ◽  
Ct Images ◽  
Ct Scans ◽  
Serial Ct ◽  
Analysis Of The Images

In this article, we analyze and report cases of three patients who were admitted to Renmin Hospital, Wuhan University, China, for treating COVID-19 pneumonia in February 2020 and were unresponsive to initial treatment of steroids. They were then received titrated steroids treatment based on the assessment of computed tomography (CT) images augmented and analyzed with the artificial intelligence (AI) tool and output. Three patients were finally recovered and discharged. The result indicated that sufficient steroids may be effective in treating the COVID-19 patients after frequent evaluation and timely adjustment according to the disease severity assessed based on the quantitative analysis of the images of serial CT scans.

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