scholarly journals A comparative study on image quality of two digital intraoral sensors

2019 ◽  
Vol 48 (7) ◽  
pp. 20190063 ◽  
Author(s):  
Cinar Aziman ◽  
Kristina Hellén-Halme ◽  
Xie-Qi Shi
Keyword(s):  
Image Quality ◽  
Observer Agreement ◽  
Visual Grading ◽  
Intra Class Correlation ◽  
Subjective Image Quality ◽  
Significant Difference ◽  
General Dentists ◽  
Parallel Technique ◽  
Specialist Group

Objectives The aims of this study were to evaluate the subjective image quality and reliability of two digital sensors. In addition, the image quality of the two sensors evaluated by specialists and general dentists were compared. Methods: 30 intraoral bitewings from five patients were included in the study, 15 were exposed with a Dixi sensor (CCD-based) and 15 with a ProSensor (CMOS-based) using modified parallel technique. Three radiologists and three general dentists evaluated the images in pair. A five-point scale was used to register the image quality. Visual grading characteristics (VGC) analysis was performed to compare the image quality and the observer agreement was assessed in terms of intra class correlation co-efficient. Results No statistically significant difference was found on image quality between the sensors. The average scores of the observer agreement were moderate with an average of 0.66 and an interval of 0.30 to 0.87, suggesting that there was a large variation on preference of image quality. However, there was a statistically significant difference in terms of the area under the VGC- curves between the specialist group and the general dentist group ( p = 0.043), in which the specialist group tended to favor the ProSensor. Conclusions Subjective image quality of the two intraoral sensors were comparable when evaluated by both general and oral radiologists. However, the radiologists seemed to prefer the ProSensor to the Dixi as compared to general dentists. Inter- observer conformance showed a large variation on the preference of the image quality.

Organ doses and subjective image quality of indirect digital panoramic radiography

2001 ◽  
Vol 30 (6) ◽  
pp. 308-313 ◽  
Author(s):  
F Gijbels ◽  
G Sanderink ◽  
C Bou Serhal ◽  
H Pauwels ◽  
R Jacobs
Keyword(s):  
Image Quality ◽  
Panoramic Radiography ◽  
Organ Doses ◽  
Subjective Image Quality ◽  
Digital Panoramic Radiography

The subjective image quality of direct digital and conventional panoramic radiography

2000 ◽  
Vol 4 (3) ◽  
pp. 162-167 ◽  
Author(s):  
F. Gijbels ◽  
A.-M. De Meyer ◽  
C. Bou Serhal ◽  
C. Van den Bossche ◽  
J. Declerck ◽  
...  
Keyword(s):  
Image Quality ◽  
Panoramic Radiography ◽  
Subjective Image Quality

Abstract WP72: Low kV Computed Tomography Cerebral Angiogram Using Third-Generation Reconstruction Algorithm Provides Significantly Improved Image Quality With Lower Contrast and Radiation Exposure

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Girish Bathla ◽  
Sarv Priya ◽  
Neetu Soni ◽  
Colin Derdeyn
Keyword(s):  
Image Quality ◽  
Radiation Exposure ◽  
Basilar Artery ◽  
Reconstruction Algorithm ◽  
Third Generation ◽  
Cerebral Angiogram ◽  
Subjective Image Quality ◽  
Contrast Dose ◽  
Significant Difference ◽  
Lower Contrast

Introduction/Aim: We aimed to determine if CTA imaging using third generation reconstruction algorithm and lower contrast dose-low kVp technique (LD-CTA) was comparable to regular contrast dose CTA at 120 kVp using a sinogram affirmed iterative reconstruction algorithm (ND-CTA). Methods: Retrospective imaging review of 100 consecutive patients (50 each in LD- and ND-CTA groups). Two readers independently assessed the subjective image quality across multiple vascular segments on a Likert-like scale. Contrast- and signal-to-noise ratios (CNR/ SNR) were compared for the mid-M1-MCA vessels bilaterally and the mid-basilar artery. Fisher’s exact test was used to compare subjective image quality. Interclass correlation coefficient (ICC) was calculated for the SNR/CNR values. Finally differences in contrast dose, CT-dose index (CTDI) and dose length product (DLP) were compared using Mann-Whitney U test. Results: Both observers showed excellent correlation in subjective image quality (mean percentage agreement of 95.2% (84-100%) for group-1 versus 89.2% (82%-98%) for group-2). The subjective scores were not statistically different in the anterior circulation but showed significantly better image quality for the basilar artery. LD-CTA group showed significantly better SNR and CNR (p < 0.0001) for both MCA vessels and the basilar artery. ICC showed moderate correlation (0.51-0.63) between the observers. Student paired t-test did not show any significant difference between the observers. LD-CTA group also used lower contrast (49 cc versus 103 cc in ND-CTA) and had lower radiation exposure (DLP/ CTDI for both groups 268.3/12.42 vs 519.5/ 25.15, both < 0.0001). Conclusion: Next-generation reconstruction algorithm and low-Kv scanning significantly improved image quality on cerebral CTA images despite lower contrast dose, and in addition, have lower radiation exposure.

The Influence of Alteration of kVp and mAs towards the Image Quality of Acrylic Using CBCT

2019 ◽  
Vol 829 ◽  
pp. 252-257
Author(s):  
Azhari ◽  
Yohanes Hutasoit ◽  
Freddy Haryanto
Keyword(s):  
Image Quality ◽  
Signal To Noise Ratio ◽  
Region Of Interest ◽  
Signal To Noise ◽  
Bite Block ◽  
Significant Difference ◽  
Noise Ratio ◽  
Post Hoc ◽  
Radiograph Image

CBCT is a modernized technology in producing radiograph image on dentistry. The image quality excellence is very important for clinicians to interpret the image, so the result of diagnosis produced becoming more accurate, appropriate, thus minimizing the working time. This research was aimed to assess the image quality using the blank acrylic phantom polymethylmethacrylate (PMMA) (C­5H8O2)n in the density of 1.185 g/cm3 for evaluating the homogeneity and uniformity of the image produced. Acrylic phantom was supported with a tripod and laid down on the chin rest of the CBCT device, then the phantom was fixed, and the edge of the phantom was touched by the bite block. Furthermore, the exposure of the X-ray was executed toward the acrylic phantom with various kVp and mAs, from 80 until 90, with the range of 5 kV and the variation of mA was 3, 5, and 7 mA respectively. The time exposure was kept constant for 25 seconds. The samples were taken from CBCT acrylic images, then as much as 5 ROIs (Region of Interest) was chosen to be analyzed. The ROIs determination was analyzed by using the ImageJ® software for recognizing the influence of kVp and mAs towards the image uniformity, noise and SNR. The lowest kVp and mAs had the result of uniformity value, homogeneity and signal to noise ratio of 11.22; 40.35; and 5.96 respectively. Meanwhile, the highest kVp and mAs had uniformity value, homogeneity and signal to noise ratio of 16.96; 26.20; and 5.95 respectively. There were significant differences between the image uniformity and homogeneity on the lowest kVp and mAs compared to the highest kVp and mAs, as analyzed with the ANOVA statistics analysis continued with the t-student post-hoc test with α = 0.05. However, there was no significant difference in SNR as analyzed with the ANOVA statistic analysis. The usage of the higher kVp and mAs caused the improvement of the image homogeneity and uniformity compared to the lower kVp and mAs.

scholarly journals Radiation dose and image quality of high-pitch emergency abdominal CT in obese patients using third-generation dual-source CT (DSCT)

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Robert Forbrig ◽  
Michael Ingrisch ◽  
Robert Stahl ◽  
Katharina Stella Winter ◽  
Maximilian Reiser ◽  
...  
Keyword(s):  
Image Quality ◽  
Radiation Dose ◽  
Third Generation ◽  
Obese Patients ◽  
Dual Source Ct ◽  
High Pitch ◽  
Subjective Image Quality ◽  
Dual Source ◽  
Group A

Abstract In this third-generation dual-source CT (DSCT) study, we retrospectively investigated radiation dose and image quality of portal-venous high-pitch emergency CT in 60 patients (28 female, mean age 56 years) with a body mass index (BMI) ≥ 30 kg/m2. Patients were dichotomized in groups A (median BMI 31.5 kg/m2; n = 33) and B (36.8 kg/m2; n = 27). Volumetric CT dose index (CTDIvol), size-specific dose estimate (SSDE), dose length product (DLP) and effective dose (ED) were assessed. Contrast-to-noise ratio (CNR) and dose-independent figure-of-merit (FOM) CNR were calculated. Subjective image quality was assessed using a five-point scale. Mean values of CTDIvol, SSDE as well as normalized DLP and ED were 7.6 ± 1.8 mGy, 8.0 ± 1.8 mGy, 304 ± 74 mGy * cm and 5.2 ± 1.3 mSv for group A, and 12.6 ± 3.7 mGy, 11.0 ± 2.6 mGy, 521 ± 157 mGy * cm and 8.9 ± 2.7 mSv for group B (p < 0.001). CNR of the liver and spleen as well as each calculated FOM CNR were significantly higher in group A (p < 0.001). Subjective image quality was good in both groups. In conclusion, third-generation abdominal high-pitch emergency DSCT yields good image quality in obese patients. Radiation dose increases in patients with a BMI > 36.8 kg/m2.

In vitro comparison of subjective image quality of the pana digital intraoral x-ray imaging system and conventional intraoral radiography in caries detection

1998 ◽  
Vol 14 (2) ◽  
pp. 75-83 ◽  
Author(s):  
Yoshiko Ariji ◽  
Jin-ichi Takahashi ◽  
Osamu Matsui ◽  
Tsuneichi Okano ◽  
Munetaka Naitoh ◽  
...  
Keyword(s):  
Image Quality ◽  
Imaging System ◽  
Caries Detection ◽  
Intraoral Radiography ◽  
Subjective Image Quality ◽  
X Ray ◽  
X Ray Imaging ◽  
In Vitro Comparison

Digital Luminescence Radiography Using a Chest Phantom

1993 ◽  
Vol 34 (5) ◽  
pp. 440-444 ◽  
Author(s):  
K. Lyttkens ◽  
M. Kehler ◽  
B. Andersson ◽  
S. Carlsen ◽  
A. Ebbesen ◽  
...  
Keyword(s):  
Image Quality ◽  
Operating Characteristic ◽  
Roc Curves ◽  
Diagnostic Image Quality ◽  
Diagnostic Image ◽  
Digital Radiographs ◽  
Significant Difference ◽  
Digital Luminescence Radiography ◽  
Optical Discs

With the introduction of picture and archiving communicating systems an alternative image display for the wards might be a personal computer (PC). The intention with this study was to evaluate the diagnostic image quality of the monitor of a PC compared to that of a workstation. Eighty-five digital radiographs of a chest phantom with simulated tumors in the mediastinum and right lung were saved on optical discs. The examinations were reviewed by 4 radiologists on a monitor at a workstation and at a PC, and receiver operating characteristic (ROC) curves were constructed. No significant difference was found between performance of the PC and the workstation.

41.4: Subjective Image Quality of Viewing Angle beyond Color Difference Metric in FPD

2013 ◽  
Vol 44 (1) ◽  
pp. 574-577
Author(s):  
Chao-Hua Wen ◽  
Yan-Yu Lin ◽  
Pin-Chou Huang ◽  
Ting-Wei Hsu ◽  
Hsin-Hong Chen ◽  
...  
Keyword(s):  
Image Quality ◽  
Color Difference ◽  
Viewing Angle ◽  
Subjective Image Quality

scholarly journals Studies on the effect of MegaPixel sensor resolution on displayed image quality and relevant metrics

2020 ◽  
Vol 2020 (9) ◽  
pp. 170-1-170-10
Author(s):  
Sophie Triantaphillidou ◽  
Jan Smejkal ◽  
Edward W. S. Fry ◽  
Chuang Hsin Hung
Keyword(s):  
Image Quality ◽  
Consumer Experience ◽  
Camera Phone ◽  
High Quality ◽  
Subjective Image Quality ◽  
Star Rating ◽  
Quality Ratings ◽  
Large Numbers ◽  
Quality Scale

This paper investigates camera phone image quality, namely the effect of sensor megapixel (MP) resolution on the perceived quality of images displayed at full size on high-quality desktop displays. For the purpose, we use images from simulated cameras with different sensor MP resolutions. We employ methods recommended in the IEEE 1858 Camera Phone Image Quality (CPIQ) standard, as well as other established psychophysical paradigms, to obtain subjective image quality ratings for systems with varying MP resolution from large numbers of observers. These are subsequently used to validate image quality metrics (IQMs) relating to sharpness and resolution, including those from the CPIQ standard. Further, we define acceptable levels of quality - when changing MP resolution - for mobile phone images in Subjective Quality Scale (SQS) units. Finally, we map SQS levels to categories obtained from star-rating experiments (commonly used to rate consumer experience). Our findings draw a relationship between the MP resolution of the camera sensor and the LCD device. The chosen metrics predict quality accurately, but only the metrics proposed by CPIQ return results in calibrated JNDs in quality. We close by discussing the appropriateness of star-rating experiments for the purpose of measuring subjective image quality and metric validation.

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