scholarly journals Using a Somatosensory Controller to Assess Body Size for Size-Specific Dose Estimates in Computed Tomography

2018 ◽  
Vol 2018 ◽  
pp. 1-7
Author(s):  
Jay Wu ◽  
Ruo-Ping Han ◽  
Yan-Lin Liu
Keyword(s):  
Computed Tomography ◽  
Body Size ◽  
Low Cost ◽  
Microsoft Kinect ◽  
Depth Image ◽  
Effective Diameter ◽  
Dose Estimation ◽  
Ct Scanner ◽  
The Mean ◽  
Anterior Posterior

Computed tomography (CT) has been widely used in the healthcare environment. Presently, the radiation dose in CT is determined using the size-specific dose estimate (SSDE). Accurate assessment of individual’s body size is essential for dose estimation. In this study, we integrated a somatosensory controller with a CT scanner to measure patient’s anterior-posterior diameter (APD) and lateral diameter (LATD) and calculate the corresponding effective diameter (ED). A total of 108 individuals with an average age of 38.6 years were enrolled in this study. Microsoft Kinect was used to acquire the depth image of subjects. A grayscale-to-surface height conversion curve was created using acrylic sheets for APD estimation. The APD, LATD, and ED were measured and compared with the results obtained using F ruler and CT images. The mean absolute differences for APD, LATD, and ED between Kinect and F ruler measurements were 5.2%, 1.3%, and 2.5%, respectively, while those between Kinect and CT measurements were 8.8%, 2.6%, and 5.0%, respectively. Kinect can replace CT or F ruler for real-time body size measurements. The use of the somatosensory controller has the advantages of simple, low cost, no radiation, and automatic calculation. It can accurately estimate patient’s APD, LATD, and ED for SSDE.

scholarly journals Comparison of the Hounsfield Unit Values Obtained From Cone-Beam Computed Tomography (CBCT) and Multidetector Computed Tomography (MDCT) Images for Different Bone Densities

2021 ◽  
Vol 7 (2) ◽  
Author(s):  
Atefeh Khavid ◽  
Mojgan Sametzadeh ◽  
Mostafa Godiny ◽  
Mohammad Mehdi Moarrefpour
Keyword(s):  
Computed Tomography ◽  
Cone Beam Computed Tomography ◽  
Pearson Correlation ◽  
Hounsfield Unit ◽  
Cone Beam ◽  
Ct Scanner ◽  
Significance Level ◽  
Dental Practitioners ◽  
Significant Difference ◽  
The Mean

Background and objective: In recent years, cone-beam computed tomography (CBCT) has become a key diagnostic tool in dentistry. CBCT can provide 3D images of the maxillofacial area to help dental practitioners in diagnosis and treatment, especially implant placement and treatment of pathogenic lesions. This study aimed to compare the Hounsfield Unit (HU) values obtained from CBCT images for bones of different densities with the corresponding HU values from MDCT images. Materials and methods: cube-shaped bone blocks of identical size were cut from the middle section of the cow ribs and femur area such that they had a layer of cortical bone in their buccal, lingual, and top surfaces and trabecular bone in the middle. MDCT scans were performed using a Somatom Sensation Ct Scanner. After determining HU from the results of these scans, nine suitable specimens from different ranges of HU were chosen for comparison. HU of the CBCT images was computed by the dedicated software of the CBCT machine. Finally, HU values obtained from MDCT and CBCT were compared. Data analysis was performed using SPSS version 25 at the 0.05 significance level. Results: The results showed a statistically significant difference between the mean HU from MDCT images and the mean HU from CBCT images (P<0.05). For similar specimens, CBCT produced higher mean HU values than MDCT. The Pearson correlation test detected a significant direct relationship between the HU values of specimens in MDCT and CBCT (P<0.05). Conclusion: For the tools and software used in this study, there was no significant difference between the HU values obtained from MDCT and CBCT, but the mean HU obtained from CBCT was higher than that from MDCT.

Correlation Between Anterior–Posterior and Lateral Dimensions with the Effective and Water-Equivalent Diameters in Axial Images From Head Computed Tomography Examinations

2021 ◽  
Author(s):  
Winda Kusuma Dewi ◽  
Choirul Anam ◽  
Eko Hidayanto ◽  
Annisa Lidia Wati ◽  
Geoff Dougherty
Keyword(s):  
Computed Tomography ◽  
Linear Correlation ◽  
Second Order ◽  
Patient Dose ◽  
Equivalent Diameter ◽  
Effective Diameter ◽  
Head Ct ◽  
Order Polynomial ◽  
Head Computed Tomography ◽  
Anterior Posterior

Abstract The study aims to correlate the effective diameter (Deff) and water-equivalent diameter (Dw) parameters with anterior–posterior (AP), lateral (LAT) and AP + LAT dimensions in order to estimate the patient dose in head CT examinations. Seventy-four patient datasets from head CT examinations were retrospectively collected. The patient’s sizes were calculated from the middle slice using a software of IndoseCT. Dw and Deff were plotted as functions of AP, LAT and AP + LAT dimensions. The best trendline fit for LAT and AP functions was a second order polynomial, which resulted in R2 of 0.89 for Deff vs LAT, 0.88 for Dw vs LAT, 0.92 for Deff vs AP and 0.91 for Dw vs AP. A linear correlation was found for Deff vs AP + LAT, Dw vs AP + LAT and Dw vs Deff with R2 of 0.97, 0.96 and 0.98, respectively.

Eye Lens Dose in Cranial Computed Tomography with Reference to the Technical Development of CT Scanners

1986 ◽  
Vol 27 (5) ◽  
pp. 599-606 ◽  
Author(s):  
U. Moström ◽  
C. Ytterbergh ◽  
K. Bergström
Keyword(s):  
Computed Tomography ◽  
Spatial Distribution ◽  
Technical Development ◽  
Cranial Computed Tomography ◽  
Eye Lens ◽  
Ct Scanner ◽  
Cranial Ct ◽  
Eye Lens Dose ◽  
Patient Groups ◽  
The Mean

The continuous technical development of cranial CT and the accumulation of clinical experience with this method, have resulted in the use of an increasing number of scan protocols for different clinical situations. An investigation was undertaken to find out how this change has influenced the dose delivered to the patient. The eye lens dose was measured at CT examinations in 245 patients, with appropriate scan protocols, and also at corresponding examinations in an anthropomorphic head phantom. One CT scanner of early (EMI CT 1010) and one of modern design (Siemens Somatom DR2) were investigated. The range of the eye lens dose was wide, namely 4 to 206 mGy for EMI CT 1010 and 6 to 124 mGy for Somatom DR2. In patient groups with comparable scan protocols the mean eye lens dose was higher with the Somatom DR2, mostly on account of a different spatial distribution of the dose in the scan plane. The dose varied less with this scanner, however, mainly because of the possibilities for more accurate positioning.

Anatomy of the Transarcuate Approach to the Petrous Apex

2008 ◽  
Vol 139 (2_suppl) ◽  
pp. P98-P98
Author(s):  
Alice D Lee ◽  
Sanaz Hamidi ◽  
Hamid R Djalilian
Keyword(s):  
Computed Tomography ◽  
High Resolution ◽  
Semicircular Canal ◽  
Petrous Apex ◽  
Minimal Risk ◽  
High Resolution Computed Tomography ◽  
Superior Semicircular Canal ◽  
The Mean ◽  
Temporal Bones ◽  
Anterior Posterior

Problem The petrous apex is considered to be one of the most difficult areas of the temporal bone to approach surgically. We present data describing the dimensions of a transarcuate approach to the petrous apex, as measured on high resolution computed tomography. Methods Measurements of the mean dimensions and ranges through the crura of the superior semicircular canal were made. The measurements were obtained from high-resolution computed tomography images of 30 temporal bones in 19 consecutively presenting patients with a pneumatized posterior petrous apex cell tract on CT. Measurements were obtained with the use of the standard PACS (picture archiving and communication system) software. Results The mean anterior-posterior space in the superior semicircular canals without transcrural pneumatization was 4.96±0.39 mm. The mean superior- inferior dimension was 4.98±0.48 mm. The same measurements in canals with pneumatized intercrural tracts were 5.17±0.51 mm and 5.11±0.62 mm respectively. The mean anterior-posterior distance and superior-inferior distance of the intercrural air tracts themselves were 2.09±0.57 and 2.01±0.45mm. There was a statistically significant difference in the anterior-posterior size between the pneumatized and non-pneumatized canals but not in the superior-inferior distance. Conclusion Pneumatized bones demonstrate a slight increase in the subarcuate dimensions as compared to non-pneumatized bones. The transarcuate approach is a viable one for drainage and biopsy of the petrous apex. Significance Our study demonstrates that the transarcuate approach is anatomically possible for drainage of the petrous apex with minimal risk to the superior semicircular canal. This would be especially useful for the drainage of cholesterol granulomas of the petrous apex or biopsy in this area.

scholarly journals Radiation Doses and Cancer Risk from CT Pulmonary Angiography Examinations

2019 ◽  
Author(s):  
Hanif Haspi Harun ◽  
Muhammad Khalis Abdul Karim ◽  
Zulkifly Abbas ◽  
Sarawana Chelwan Muniandy ◽  
Akmal Sabarudin ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Radiation Dose ◽  
Cancer Risk ◽  
Organ Dose ◽  
Pulmonary Angiography ◽  
Effective Diameter ◽  
Radiological Protection ◽  
Radiation Doses ◽  
Dose Length Product ◽  
The Mean

The present study aims to investigate radiation doses from Computed Tomography Pulmonary Angiography (CTPA) examinations based on the patient&rsquo;s size and to estimate the probability of cancer risk induced from the examination. Data from 100 patients who had undergone CTPA examinations, such as scanning acquisition parameters, patient demography, as well as radiation dose exposure, were collected and analysed. All subjects which aged above 18 y/o were scanned using a Philips Brilliance 128 multi-detector CT (MDCT) scanner. The mean dose value for Volume Computed Tomography Dose Index (CTDIvol), Dose-Length Product (DLP) and effective dose (E) were 11.06 &plusmn; 7.17 mGy, 400.38 &plusmn; 259.10 mGy.cm and 8.68 &plusmn; 5.47 mSv respectively. In addition, with respective of patient&rsquo;s effective diameter, the mean SSDE value for Group 1, Group 2 and Group 3 were 9.93 &plusmn; 3.89, 13.70 &plusmn; 9.04 and 22.29 &plusmn; 7.35, respectively. Cancer risk per million procedure was calculated based on te recommendation by the International Commission on Radiological Protection Publication 103 report. The organ dose and cancer risk attained for breast, lung and liver were 17.05 &plusmn; 10.40 mGy (194 per one million procedure), 17.55 &plusmn; 10.86 mGy (192 per one million procedure) and 15.04 &plusmn; 9.75 mGy (53 per one million procedure), respectively. In conclusion, CTDIvol underestimated, and SSDE was more accurate in describing the radiation dose. Lung and breast with larger lung effective diameter received the highest dose exposure which increase the probability of the cancer risk. Therefore, it is important to apply optimised protocols in order to reduce patient&rsquo;s exposure during CTPA examination.

scholarly journals Preliminary development of computed tomography (CT) scanner using transillumination imaging

10.29007/kgfg ◽  
2020 ◽  
Author(s):  
Ngoc An Dang Nguyen ◽  
To Ni Phan Van ◽  
Ngoc Anh Tuan Vo ◽  
Van Phu Le ◽  
Anh Tu Tran ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Blood Vessel ◽  
Near Infrared ◽  
Light Emitting Diode ◽  
Low Cost ◽  
Animal Experiments ◽  
Three Dimensional ◽  
Small Animal ◽  
Body Parts ◽  
Ct Scanner

Near-infrared transillumination imaging is useful in many biomedical applications such as human biometrics and animal experiments. Using near-infrared (NIR) light, we can able to obtain a two dimensional (2D) transillumination image of the internal absorption structure such as blood vessel structure, liver ... in a small animal body. If we can obtain projection images from many orientations, we can reconstruct a three dimensional (3D) image using various computed tomography techniques. In previous studies of our group, even with a simple system (light-emitting diode (LED)'s array and low-cost camera), we can obtain the blood vessel transillumination image of the human arm. In this paper, we propose preliminary research on the development of a computed tomography (CT) scanner prototype of human body parts using transillumination imaging.

scholarly journals A New Automated Way to Measure Polyethylene Wear in THA Using a High Resolution CT Scanner: Method and Analysis

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Gerald Q. Maguire Jr. ◽  
Marilyn E. Noz ◽  
Henrik Olivecrona ◽  
Michael P. Zeleznik ◽  
Lars Weidenhielm
Keyword(s):  
Computed Tomography ◽  
Femoral Component ◽  
Polyethylene Wear ◽  
Human Interaction ◽  
Ct Scanner ◽  
Acetabular Cup ◽  
Computed Tomography Imaging ◽  
The Mean ◽  
Active Patients ◽  
Ct Volume

As the most advantageous total hip arthroplasty (THA) operation is the first, timely replacement of only the liner is socially and economically important because the utilization of THA is increasing as younger and more active patients are receiving implants and they are living longer. Automatic algorithms were developed to infer liner wear by estimating the separation between the acetabular cup and femoral component head given a computed tomography (CT) volume. Two series of CT volumes of a hip phantom were acquired with the femoral component head placed at 14 different positions relative to the acetabular cup. The mean and standard deviation (SD) of the diameter of the acetabular cup and femoral component head, in addition to the range of error in the expected wear values and the repeatability of all the measurements, were calculated. The algorithms resulted in a mean (±SD) for the diameter of the acetabular cup of 54.21 (±0.011) mm and for the femoral component head of 22.09 (±0.02) mm. The wear error was ±0.1 mm and the repeatability was 0.077 mm. This approach is applicable clinically as it utilizes readily available computed tomography imaging systems and requires only five minutes of human interaction.

A Low Cost System for 3D Motion Analysis Using Microsoft Kinect

2013 ◽  
Vol 284-287 ◽  
pp. 1996-2000 ◽  
Author(s):  
Hai Trieu Pham ◽  
Jung Ja Kim ◽  
Yong Gwan Won
Keyword(s):  
Motion Analysis ◽  
Color Image ◽  
Low Cost ◽  
Infrared Camera ◽  
Microsoft Kinect ◽  
Depth Image ◽  
3D Motion ◽  
Acceptable Accuracy ◽  
3D Motion Analysis ◽  
Analysis System

Many motion analysis systems which have been introduced in the past few years are currently receiving interests from researchers and developers due to their usefulness and wide application capability in the future. However, many of those systems meet with difficulties for the real applications because of high cost for the implementation and less accuracy. This paper introduces a new 3D motion analysis system which can be implemented at a lower cost and acceptable accuracy for various applications. The key component of our new system is the use of the MSK (Microsoft Kinect) sensor system which is equipped with both visual camera and infrared camera. It can provide the color image, the 3D depth image and the 3D skeleton data without wearing any marker device on the human body while it can provide acceptable accuracy in 3D motion trace at low cost. Our system can be exploited for a base framework for various 3D motion-based applications such as physical rehabilitation support, sport motion analysis and biomechanical applications.

Intraoperative Computed Tomography for Registration of Stereotactic Frame in Frame-Based Deep Brain Stimulation

2020 ◽  
Author(s):  
Michael R Jones ◽  
Archit B Baskaran ◽  
Mark J Nolt ◽  
Joshua M Rosenow
Keyword(s):  
Computed Tomography ◽  
Deep Brain Stimulation ◽  
Electrode Placement ◽  
Absolute Difference ◽  
Ct Scanner ◽  
Intraoperative Ct ◽  
Stereotactic Frame ◽  
The Mean ◽  
Conventional Ct ◽  
Deep Brain

Abstract BACKGROUND Deep brain stimulation (DBS) electrode placement utilizing a frame-based technique requires registration of the stereotactic frame with computed tomography (CT) or magnetic resonance (MR) imaging. This traditionally has been accomplished with a conventional CT scanner. In recent years, intraoperative CT has become more prevalent. OBJECTIVE To compare the coordinates obtained with intraoperative CT and conventional CT for registration of the stereotactic frame for DBS. METHODS Patients undergoing DBS electrode placement between 2015 and 2017, who underwent both conventional and intraoperative CT for registration of the stereotactic frame, were included for analysis. The coordinates for the stereotactic target, anterior commissure, and posterior commissure for each CT method were recorded. The mean, maximum, minimum, and standard deviation of the absolute difference for each of the paired coordinates was calculated. Paired t-tests were performed to test for statistical significance of the difference. The directional difference as well as the vector error between the paired coordinates was also calculated. RESULTS The mean absolute difference between conventional and intraoperative CT for the coordinate pairs was less than 0.279 mm or 0.211 degrees for all coordinate pairs analyzed. This was not statistically significant for any of the coordinate pairs. Moreover, the maximum absolute difference between all coordinate pairs was 1.04 mm. CONCLUSION Intraoperative CT imaging provides stereotactic frame registration coordinates that are similar to those obtained by a standard CT scanner. This may save time and hospital resources by obviating the need for the patient to go to the radiology department for a CT scan.

scholarly journals The effective and water-equivalent diameters as geometrical size functions for estimating CT dose in the thoracic, abdominal, and pelvic regions

2021 ◽  
Vol 27 (3) ◽  
pp. 213-222
Author(s):  
Winda Kusuma Dewi ◽  
Choirul Anam ◽  
Eko Hidayanto ◽  
Arrum Nitasari ◽  
Geoff Dougherty
Keyword(s):  
Computed Tomography ◽  
Equivalent Diameter ◽  
Effective Diameter ◽  
Strong Correlations ◽  
Thoracic Region ◽  
Specific Patient ◽  
Geometrical Size ◽  
Ct Dose ◽  
Patient Size ◽  
Anterior Posterior

Abstract Purpose: The aim of this work was to establish the relationships of patient size in terms of effective diameter (Deff) and water-equivalent diameter (Dw) with lateral (LAT) and anterior-posterior (AP) dimensions in order to predict the specific patient dose for thoracic, abdominal, and pelvic computed tomography (CT) examinations. Methods: A total of 47 thoracic images, 79 abdominal images, and 50 pelvic images were analyzed in this study. The patient’s images were retrospectively collected from Dr. Kariadi and Kensaras Hospitals, Semarang, Indonesia. The slices measured were taken from the middle of the scan range. The calculations of patient sizes (LAT, AP, Deff, and Dw) were automatically performed by IndoseCT 20b software. Deff and Dw were plotted as functions of LAT, AP, and AP+LAT. In addition, Dw was plotted as a function of Deff. Results: Strong correlations of Deff and Dw with LAT, AP, and AP+LAT were found. Stronger correlations were found in the Deff curves (R2 > 0.9) than in the Dw curves (R2 > 0.8). It was found that the average Deff was higher than the average Dw in the thoracic region, the average values were similar in the abdominal and pelvic regions. Conclusion: The current study extended the study of the relationships between Deff and Dw and the basic geometric diameter LAT, AP, and AP+LAT beyond those previously reported by AAPM. We evaluated the relationships for three regions, i.e. thoracic, abdominal, and pelvic regions. Based on our findings, it was possible to estimate Deff and Dw from only the LAT or AP dimension.

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