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Objective: To assess the dose reduction potential of a calcium-aware reconstruction technique, which aims at tube voltage-independent computed tomography (CT) numbers for calcium.Methods and Materials: A cardiothoracic phantom, mimicking three different patient sizes, was scanned with two calcium inserts (named D100 and CCI), containing calcifications varying in size and density. Tube voltage was varied both manually (range 70-150 and Sn100 kVp) and automatically. Tube current was automatically adapted to maintain reference image quality defined at 120 kVp. Data was reconstructed with the standard reconstruction technique (kernel Qr36) and the calcium-aware reconstruction technique (kernel Sa36). We assessed the radiation dose reduction potential (volumetric CT dose index values (CTDIvol)), noise (standard deviation (SD)), mean CT number (HU) of each calcification, and Agatston scores for varying kVp. Results were compared with the reference acquired at 120 kVp and reconstructed with Qr36.Results: Automatic selection of the optimal tube voltage resulted in a CTDIvol reduction of 22%, 15%, and 12% compared with the reference for the small, medium, and large phantom, respectively. CT numbers differed up to 64% for the standard reconstruction and 11% for the calcium-aware reconstruction. Similarly, Agatston scores deviated up to 40% and 8% for the standard and calcium-aware reconstruction technique, respectively.Conclusion: CT numbers remained consistent with comparable calcium scores when the calcium-aware image reconstruction technique was applied with varying tube voltage. Less consistency was observed in small calcifications with low density. Automatic reduction of tube voltage resulted in a dose reduction of up to 22%.Key Points: • The calcium-aware image reconstruction technique allows for consistent CT numbers when varying the tube voltage. • Automatic reduction of tube voltage results in a reduced radiation exposure of up to 22%. • This study stresses the known limitations of the current Agatston score technique. [ABSTRACT FROM AUTHOR]

Objective: A tonsillolith is a concretion of the tonsillar crypt. The aim of this retrospective study was to compare panoramic radiography (PR) and cone-beam computed tomography (CBCT) for the detection of tonsilloliths.Materials and Methods: The CBCT images of 527 patients with maxillofacial volume were evaluated retrospectively. Of these, 175 patients (81 females, 94 males; mean age 51.05 years) had unilateral or bilateral tonsilloliths. In total, 151 of them (67 females, 84 males; mean age, 51.03 years) had PR images performed in the same period and were included in the study. The PR images were examined to ascertain whether known tonsilloliths (from CBCT images) could be detected. The location (unilateral; left or right and bilateral), size, and number of the tonsilloliths were examined on both CBCT and PR images. Descriptive analysis, Spearman's rho correlation coefficient, and χ2 tests were used for the statistical analysis.Results: The detection rate of tonsillolith was 33.2% on CBCT images. Only 51.4% of the tonsilloliths detected on CBCT were evaluated by PR; the correlation between CBCT and PR was found to be significant (Spearman's r = 0.399, p = 0.000). PR was not adequate to detect tonsilloliths 1 mm or smaller in size. All the calcifications larger than 5 mm were detected on PR images.Conclusion: The results of this study showed that more than half of the tonsilloliths observed in CBCT were also detected in PR. Tonsilloliths larger than 2 mm were more likely to be detected on PR images. [ABSTRACT FROM AUTHOR]

Dystrophic calcinosis is a condition wherein calcium is deposited in degenerated tissues, often associated with trauma, infection, or inflammation, in the absence of a systemic mineral imbalance. It commonly occurs in cardiac and skeletal muscles; rarely in oral and perioral region. We report a unique case of a 25-year-old healthy male, with dystrophic calcinosis in the subcutaneous tissues of the cheek overlying the right body of the mandible, with history of infection in that region. CT and CBCT examination revealed multiple irregular to curvi-linear shaped radiodense calcified structures, discrete from the mandibular buccal cortex. The calcified structures were surgically removed via extra oral approach without complications. Although soft tissues of the cheek do not frequently contain lesions that include calcifications, dystrophic calcinosis must be considered among the differentials for calcified masses in the oral region, particularly when infection is present. Its preoperative diagnosis poses a challenge in view of differential diagnosis. [ABSTRACT FROM AUTHOR]

Objective: To determine the prevalence of soft tissue calcifications in cone beam computed tomography (CBCT) scans with different fields of view (FOV) and to assess its relation with the clinical relevance of the CBCT findings. Material and Methods: One thousand CBCT scans were grouped according to FOV's size and region scanned (MX‐FOV, maxilla; MD‐FOV, mandible; and MM‐FOV, maxilla/mandible) and evaluated for the presence of soft tissue calcifications. Laterality and length of the elongated styloid processes (ESP) were also assessed. Results: Eight hundred and eighty‐two soft tissue calcifications were detected in 626 (62.6%) patients. MM‐FOV presented the highest prevalence (76.8%), followed by MD‐FOV (60.6%) and MX‐FOV (57.2%). ESP and tonsillolith were the most frequent calcifications. Calcifications requiring treatment or not and those in need of follow‐up accounted for 6.9%, 92.7%, and 0.3% of cases, respectively. There was no association between calcifications and subjects’ gender or age (p > .05). Most cases of ESP occurred bilaterally and were longer in males (p < .05). Conclusions: There is a high prevalence of soft tissue calcifications in CBCT, and ESP and tonsilloliths are the most common types in all evaluated FOVs. While most cases do not require treatment, we emphasize the importance of detailed CBCT assessment for its diagnosis. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aim of this study was to establish an anatomical guideline in cone beam computed tomography (CBCT) images to discriminate soft-tissue calcifications, specifically, tonsilloliths, and styloid chain ossification (SCO) in the multiplanar reconstruction screen of the i-CAT Vision. MATERIALS AND METHODS: We analyzed 100 pairs of CBCT images and panoramic digital radiographies regarding the presence or absence of tonsilloliths and SCO. The intraobserver agreement varied from excellent to good. The statistical analyses included Mann-Whitney test, chi-square test, Spearman test, Student's t-test, and Wilcoxon test. The analyses were repeated without the guideline to verify its effectiveness. RESULTS: A total of 25 tonsilloliths were found in panoramic images while CBCT images revealed 60. Panoramic and CBCT images showed 42% and 63% of patients positive to SCO, respectively. We found a statistically significant difference when comparing the presence of tonsilloliths and SCO between panoramic and CBCT images (Wilcoxon test P < 0.05). The analyses without the guideline showed that the observer tended to diagnoses more false-positive SCO. CONCLUSION: Based on the results, we can suggest that CBCT images are more suitable to differentiate tonsilloliths and SCO than panoramic images. The guideline was more important to diagnosis SCO than tonsilloliths. SCO was misclassified in 34% without the guideline. [ABSTRACT FROM AUTHOR]