We report our initial clinical experience for image quality and diagnostic performance of a digital PET prototype scanner with time-of-flight (DigitalTF), compared with an analog PET scanner with time-of-flight (GeminiTF PET/CT). Methods: Twenty-one oncologic patients, mean age 58 y, first underwent clinical 18 F-FDG PET/CT on the GeminiTF. The scanner table was then withdrawn while the patient remained on the table, and the DigitalTF was inserted between the GeminiTF PET and CT scanner. The patients were scanned for a second time using the same PET field of view with CT from the GeminiTF for attenuation correction. Two interpreters reviewed the 2 sets of PET/CT images for overall image quality, lesion conspicuity, and sharpness. They counted the number of suggestive 18 F-FDG-avid lesions and provided the TNM staging for the 5 patients referred for initial staging. Standardized uptake values (SUVs) and SUV gradients as a measure of lesion sharpness were obtained. Results: The DigitalTF showed better image quality than the GeminiTF. In a side-by-side comparison using a 5-point scale, lesion conspicuity (4.3 ± 0.6), lesion sharpness (4.3 ± 0.6), and diagnostic confidence (3.4 ± 0.7) were better with DigitalTF than with GeminiTF (P , 0.01). In 52 representative lesions, the lesion maximum SUV was 36% higher with DigitalTF than with GeminiTF, lesion-toblood-pool SUV ratio was 59% higher, and SUV gradient was 51% higher, with good correlation between the 2 scanners. Lesions less than 1.5 cm showed a greater increase in SUV from GeminiTF to DigitalTF than those lesions 1.5 cm or greater. In 5 of 21 patients, DigitalTF showed an additional 8 suggestive lesions that were not seen using GeminiTF. In the 15 restaging patients, the true-negative rate was 100% and true-positive rate was 78% for both scanners. In the 5 patients for initial staging, DigitalTF led to upstaging in 2 patients and showed the same staging in the other 3 patients, compared with GeminiTF. Conclusion: DigitalTF provides better image quality, diagnostic confidence, and accuracy than GeminiTF. DigitalTF may be the most beneficial in detecting small tumor lesions and disease staging. PETcont inues to play a significant role in molecular imaging.Steady improvements in detector design and architecture as well as the implementation of time-of-flight (TOF) technology have created significant improvements in image quality and greater flexibility in reducing radiotracer dose and scanning time (1-4).The current trend in molecular imaging places emphasis on accurate, quantitative PET imaging for improved lesion characterization and treatment monitoring (5). A new type of scintillation detector, digital photon counters (DPC), was recently developed by Philips Healthcare (6-8). The key innovation of the new digital PET system is the replacement of conventional photomultipliers with high-performance digital detectors and the implementation of singlephoton avalanche photodiodes with low-voltage complementary metal-oxide semiconductor (CMOS) logic on the same silico...

Background:We have previously shown an increased incidence of intermittent hypoxemia (Ih) events in preterm infants with severe retinopathy of prematurity (ROP). animal models suggest that patterns of Ih events may play a role in ROP severity as well. We hypothesize that specific Ih event patterns are associated with ROP in preterm infants. Methods: Variability in Ih event duration, severity, and the time interval between Ih events (≤80%, ≥10 s, and ≤3 min) along with the frequency spectrum of the oxygen saturation (spO 2 ) waveform were assessed. results: severe ROP was associated with (i) an increased mean and sD of the duration of Ih event (P < 0.005), (ii) more variability (histogram entropy) of the time interval between Ih events (P < 0.005), (iii) a higher Ih nadir (P < 0.05), (iv) a time interval between Ih events of 1-20 min (P < 0.05), and (v) increased spectral power in the range of 0.002-0.008 hz (P < 0.05), corresponding to spO 2 waveform oscillations of 2-8 min in duration. spectral differences were detected as early as 14 d of life. conclusion: severe ROP was associated with more variable, longer, and less severe Ih events. Identification of specific spectral components in the spO 2 waveform may assist in early identification of infants at risk for severe ROP.

Patients with systemic lupus erythematosus (SLE) are at increased risk for cardiovascular (CV) disease. The aim of this study was to investigate the association between subclinical CV disease as measured by carotid intima-media thickness (IMT) and plaque using B-mode carotid ultrasound and incident CV events in a combined cohort of female patients with SLE. This was a prospective, 2-center observational study of 392 adult women with SLE and no previous CV events with a mean 8 years of follow-up. Incident CV events confirmed by clinicians were defined as angina, myocardial infarction, percutaneous transluminal coronary angioplasty, coronary artery bypass graft, fatal cardiac arrest, transient ischemic attack, and cerebrovascular accident. Incident hard CV events excluded angina and transient ischemic attack. The mean age was 43.5 years, and most patients were Caucasian (77.3%). During follow-up, 38 patients had incident CV events, and 17 had incident hard CV events. Patients with incident hard CV events had higher mean carotid IMT (0.80 vs 0.64 mm, p <0.01) and presence of carotid plaque (76.5% vs 30.4%, p <0.01) compared with those without incident hard CV events. Baseline carotid IMT and presence of plaque were predictive of any incident hard CV event (hazard ratio 1.35, 95% confidence interval 1.12 to 1.64, and hazard ratio 4.26, 95% confidence interval 1.23 to 14.83, respectively), independent of traditional CV risk factors and medication use. In conclusion, in women with SLE without previous CV events, carotid IMT and plaque are predictive of future CV events. This suggests that carotid ultrasound may provide an additional tool for CV risk stratification in patients with SLE.

Background Subclinical cognitive impairment is prevalent in heart failure (HF); however, its role in important clinical outcomes, such as HF treatment adherence, is unclear. Given the complex polypharmacy in HF treatment, cognitive deficits may be important in predicting medication management. Thus, the objective of the current study was to examine the impact of cognitive function on medication adherence among community-dwelling patients with HF using objective assessments. Methods and Results A prospective observational cohort design of 309 community-dwelling patients with HF (59.7% male, 68.7±9.7 years) and no history of dementia or neurological disease. Cognition was assessed using a neuropsychological battery at baseline. Medication adherence was objectively measured for 21 days using an electronic pillbox. Regression analyses tested whether attention, executive function, or memory predicted 21-day medication adherence. In unadjusted analyses, lower scores on all three cognitive domains predicted poorer medication adherence (β = .52–85, p = .001–.009). After adjusting for demographic, clinical, and psychosocial variables, memory continued to predict medication adherence (β = 0.51, p = .008), whereas executive function (β = 0.24 p = .075), and attention were no longer a predictor (β = 0.34, p = .131). Conclusions Poorer cognitive function, especially in regard to memory, predicted reduced medication adherence among patients with HF and no history of dementia. This effect remained after adjustment for factors known to predict adherence, such as depressed mood, social support, and disease severity level. Future studies should examine the link from cognitive impairment and medication non-adherence to clinical outcomes (e.g., hospitalization and mortality). Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT01461629.

Therapeutic, IV.