Day-to-Day Test–Retest Variability of CBF, CMRO2, and OEF Measurements Using Dynamic 15O PET Studies

Applicability of emission-based attenuation map for rapid CBF, OEF, and CMRO2 measurements using gaseous 15O-labeled compounds

BACKGROUND Cerebral blood flow (CBF), oxygen extraction fraction (OEF), and cerebral metabolic rate of oxygen (CMRO2) images have facilitated understanding of the pathophysiological basis of cerebrovascular disorders. Such parametric images can be rapidly, measured within around 15 min, using positron emission tomography (PET) with sequentially administered (15)O-labeled oxygen and water. For f...

stability and attraction domains of traffic equilibria in day-to-day dynamical system formulation

در این پژوهش مسئله واگذاری ترافیک را از دید سیستم های دینامیکی فرمول بندی می کنیم.فرض کرده ایم که همه فاکتورهای وابسته در طول زمان ثابت باشند و تعادل کاربر را از طریق فرایند منظم روزبه روز پیگیری کنیم.دینامیک ترافیک توسط یک نگاشت بازگشتی نشان داده می شود که تکامل سیستم در طول زمان را نشان می دهد.پایداری تعادل و دامنه جذب را توسط مطالعه ویژگی های توپولوژیکی تکامل سیستم تجزیه و تحلیل می کنیم.پاید...

Rapid quantitative CBF and CMRO2 measurements from a single PET scan with sequential administration of dual 15O-labeled tracers

Positron emission tomography (PET) with (15)O tracers provides essential information in patients with cerebral vascular disorders, such as cerebral blood flow (CBF), oxygen extraction fraction (OEF), and metabolic rate of oxygen (CMRO(2)). However, most of techniques require an additional C(15)O scan for compensating cerebral blood volume (CBV). We aimed to establish a technique to calculate al...

Oxygen-15 labeled CO2, O2, and CO PET in small animals: evaluation using a 3D-mode microPET scanner and impact of reconstruction algorithms

BACKGROUND Positron emission tomography (PET) studies using 15O-labeled CO2, O2, and CO have been used in humans to evaluate cerebral blood flow (CBF), the cerebral oxygen extraction fraction (OEF), and the cerebral metabolic rate of oxygen (CMRO2) and cerebral blood volume (CBV), respectively. In preclinical studies, however, PET studies using 15O-labeled gases are not widely performed because...

Day-to-day blood pressure variability and dementia