Objective The feasibility of a fluoride positron emission tomography/computed tomography (PET/CT) scan for imaging atherosclerosis has not been well documented. The purpose of this study was to assess fluoride uptake of vascular calcification in various major arteries, including coronary arteries. Methods We retrospectively reviewed the imaging data and cardiovascular history of 61 patients who received whole-body sodium [¹⁸F]fluoride PET/CT studies at our institution from 2009 to 2010. Fluoride uptake and calcification in major arteries, including coronary arteries, were analyzed by both visual assessment and standardized uptake value measurement. Results Fluoride uptake in vascular walls was demonstrated in 361 sites of 54 (96%) patients, whereas calcification was observed in 317 sites of 49 (88%) patients. Significant correlation between fluoride uptake and calcification was observed in most of the arterial walls, except in those of the abdominal aorta. Fluoride uptake in coronary arteries was demonstrated in 28 (46%) patients and coronary calcifications were observed in 34 (56%) patients. There was significant correlation between history of cardiovascular events and presence of fluoride uptake in coronary arteries. The coronary fluoride uptake value in patients with cardiovascular events was significantly higher than in patients without cardiovascular events. Conclusion sodium [¹⁸F]fluoride PET/CT might be useful in the evaluation of the atherosclerotic process in major arteries, including coronary arteries. An increased fluoride uptake in coronary arteries may be associated with an increased cardiovascular risk.

Objective: To explore the neuropsychological sequelae of blast-induced mild traumatic brain injury (mTBI) and posttraumatic stress disorder (PTSD), several neuropsychological tests and self-reported measures of cognitive and emotional functioning were administered to 138 Operation Iraqi Freedom (OIF)/Operation Enduring Freedom (OEF) veterans. We hypothesized that veterans affected by mTBI and PTSD would manifest differences in neuropsychological testing and self-report measures compared to a group of healthy veteran controls and to veterans with only PTSD. Method: Participants included 3 groups of veterans: (a) healthy controls (n = 43); (b) PTSD only (n = 48); and (c) comorbid blast-induced mTBI and PTSD (n = 47). An exploratory factor analysis (EFA) was used to extract a smaller number of latent dimensions for group comparison. Results: The EFA suppo, ted an 8-factor model. A multivariate analysis of variance on the 8 factor scores demonstrated 3 significant factor mean differences: (a) perceived cognitive complications (PCC), (b) perceived emotional distress (PED), and (c) processing speed (PS). Post hoc analyses showed significant group mean difference in PS between the comorbid and the control groups. In addition, the comerbid group presented with the highest levels of PCC and PED. Conclusions: Results suggest that among OIF/OEF veterans with blast-induced mTBI, PTSD with its accompanying emotional distress may be a significant determinant of subjective sense of well-being both cognitively and emotionally. The objective discrepancy in PS between the comorbid group and the healthy controls also appears largely due to PTSD more so than the remote blast-induced mTBI, as the group mean difference in PS became negligible after controlling for PTSD levels.

¹²³I thyroid scintigraphy can be performed with either a low energy or medium energy collimator. The high-energy photon emissions from ¹²³I cause septal penetration with scattered photons, which deteriorate image quality. The aim of this study is to evaluate the impact of collimator choice on ¹²³I thyroid scintigraphy in clinical practice. Methods: Forty seven patients who received thyroid planar scintigraphy with both a low energy high resolution (LEHR) collimator and a medium energy (ME) collimator were prospectively recruited using the same imaging protocol. Image quality, collimator sensitivity, and estimation of thyroid size were assessed between LEHR and ME collimators, and were compared with thyroid ultrasonography as the gold standard. Results: Images acquired with the ME collimator demonstrate less scattered background noise, improved thyroid to background contrast, and increased sensitivity in the thyroid gland compared to images acquired by the LEHR collimator. Manual measurement of the thyroid length is more accurate by using the ME collimator. Automatic estimation of the thyroid area size by using the same thyroid cutoff threshold is larger in ME collimator images than in LEHR collimator images. Conclusion:¹²³I thyroid scintigraphy using the ME collimator generates cleaner images with less background noise and has higher collimator sensitivity for thyroid imaging compared to the LEHR collimator. Different thyroid cutoff threshold should be used to estimate the thyroid area size and volume between low and medium energy collimators.