Utility of the 16-cm Axial Volume Scan Technique for Coronary Artery Calcium Scoring on Non-Enhanced Chest CT: A Prospective Pilot Study.

Purpose: This study aimed to evaluate the utility of the 16-cm axial volume scan technique for calculating the coronary artery calcium score (CACS) using non-enhanced chest CT. Materials and Methods: This study prospectively enrolled 20 participants who underwent both, non-enhanced chest CT (16-cm-coverage axial volume scan technique) and calcium-score CT, with the same parameters, differing only in slice thickness (in non-enhanced chest CT = 0.625, 1.25, 2.5 mm; in calcium score CT = 2.5 mm). The CACS was calculated using the conventional Agatston method. The difference between the CACS obtained from the two CT scans was compared, and the degree of agreement for the clinical significance of the CACS was confirmed through sectional analysis. Each calcified lesion was classified by location and size, and a one-to-one comparison of non-contrast-enhanced chest CT and calcium score CT was performed. Results: The correlation coefficients of the CACS obtained from the two CT scans for slice thickness of 2.5, 1.25, and 0.625 mm were 0.9850, 0.9688, and 0.9834, respectively. The mean differences between the CACS were -21.4% at 0.625 mm, -39.4% at 1.25 mm, and -76.2% at 2.5 mm slice thicknesses. Sectional analysis revealed that 16 (80%), 16 (80%), and 13 (65%) patients showed agreement for the degree of coronary artery disease at each slice interval, respectively. Inter-reader agreement was high for each slice interval. The 0.625 mm CT showed the highest sensitivity for detecting calcified lesions. Conclusion: The values in the non-contrast-enhanced chest CT, using the 16-cm axial volume scan technique, were similar to those obtained using the CACS in the calcium score CT, at 0.625 mm slice thickness without electrocardiogram gating. This can ultimately help predict cardiovascular risk without additional radiation exposure.

Etiology of Nasal Bone Fractures.

The aim of this study was to perform a systematic review of the etiology of nasal bone fractures (NBFs).In PubMed (500 titles) and Scopus (272), the search terms "nasal bone fracture" AND "etiology OR cause" were used. Among the 772 titles, 137 were duplicated and excluded. The 552 titles were excluded and 83 abstracts were read. Subsequently, 42 abstracts were excluded and 41 full articles providing data on etiologies of NBFs were reviewed. Finally, 26 papers were incorporated into this analysis.The causes of NBFs were different between adults and children. In adults, the most frequent causes were fights (36.3%), traffic accidents (20.8%), sports (15.3%), and falls (13.4%). In children, the most frequent causes were sports (59.3%), fights (10.8%), traffic accidents (8.3%), collisions (5.0%), and falls (3.3%). It is noticeable that fights, traffic accidents, and falls were more frequent in adults than in children, although sports and collisions were more frequent in children than in adults (P < 0.001). The causes of NBFs varied geographically. Fights were the most frequent cause in Asia (36.7%), South America (46.5%), and Europe (40.8%). In North America, however, traffic accidents were the most frequent cause (33.6%), followed by fights (20.7%) and sports (17.3%). Among the sports injuries, ball-related sports were the most frequent cause (84.2%). Fighting-related sports (6.4%) contributed to relatively small proportion of NBFs.In efforts to prevent NBFs in children, sports injuries should be primarily considered. Restraining devices such as seatbelts are needed to prevent NBFs caused by traffic accidents, especially in North America.

Detection and spatial mapping of mercury contamination in water samples using a smart-phone.

Detection of environmental contamination such as trace-level toxic heavy metal ions mostly relies on bulky and costly analytical instruments. However, a considerable global need exists for portable, rapid, specific, sensitive, and cost-effective detection techniques that can be used in resource-limited and field settings. Here we introduce a smart-phone-based hand-held platform that allows the quantification of mercury(II) ions in water samples with parts per billion (ppb) level of sensitivity. For this task, we created an integrated opto-mechanical attachment to the built-in camera module of a smart-phone to digitally quantify mercury concentration using a plasmonic gold nanoparticle (Au NP) and aptamer based colorimetric transmission assay that is implemented in disposable test tubes. With this smart-phone attachment that weighs <40 g, we quantified mercury(II) ion concentration in water samples by using a two-color ratiometric method employing light-emitting diodes (LEDs) at 523 and 625 nm, where a custom-developed smart application was utilized to process each acquired transmission image on the same phone to achieve a limit of detection of ∼ 3.5 ppb. Using this smart-phone-based detection platform, we generated a mercury contamination map by measuring water samples at over 50 locations in California (USA), taken from city tap water sources, rivers, lakes, and beaches. With its cost-effective design, field-portability, and wireless data connectivity, this sensitive and specific heavy metal detection platform running on cellphones could be rather useful for distributed sensing, tracking, and sharing of water contamination information as a function of both space and time.

Fluorescent imaging of single nanoparticles and viruses on a smart phone.

Optical imaging of nanoscale objects, whether it is based on scattering or fluorescence, is a challenging task due to reduced detection signal-to-noise ratio and contrast at subwavelength dimensions. Here, we report a field-portable fluorescence microscopy platform installed on a smart phone for imaging of individual nanoparticles as well as viruses using a lightweight and compact opto-mechanical attachment to the existing camera module of the cell phone. This hand-held fluorescent imaging device utilizes (i) a compact 450 nm laser diode that creates oblique excitation on the sample plane with an incidence angle of ~75°, (ii) a long-pass thin-film interference filter to reject the scattered excitation light, (iii) an external lens creating 2× optical magnification, and (iv) a translation stage for focus adjustment. We tested the imaging performance of this smart-phone-enabled microscopy platform by detecting isolated 100 nm fluorescent particles as well as individual human cytomegaloviruses that are fluorescently labeled. The size of each detected nano-object on the cell phone platform was validated using scanning electron microscopy images of the same samples. This field-portable fluorescence microscopy attachment to the cell phone, weighing only ~186 g, could be used for specific and sensitive imaging of subwavelength objects including various bacteria and viruses and, therefore, could provide a valuable platform for the practice of nanotechnology in field settings and for conducting viral load measurements and other biomedical tests even in remote and resource-limited environments.