This proposal for standardization of (123)I-metaiodobenzylguanidine (iobenguane, MIBG) cardiac sympathetic imaging includes recommendations for patient information and preparation, radiopharmaceutical, injected activities and dosimetry, image acquisition, quality control, reconstruction methods, attenuation, scatter and collimator response compensation, data analysis and interpretation, reports, and image display. The recommendations are based on evidence coming from original or scientific studies whenever possible and as far as possible reflect the current state-of-the-art in cardiac MIBG imaging. The recommendations are designed to assist in the practice of performing, interpreting and reporting cardiac sympathetic imaging. The proposed standardization does not include clinical indications, benefits or drawbacks of cardiac sympathetic imaging, and does not address cost benefits or cost effectiveness; however, clinical settings of potential utility are mentioned. Standardization of MIBG cardiac sympathetic imaging should contribute to increasing its clinical applicability and integration into current nuclear cardiology practice.

Rationale: Ayahuasca is a South American psychoactive plant tea which contains the serotonergic psychedelic N,N-dimethyltryptamine (DMT) and monoamine-oxidase inhibitors that render DMT orally active. Previous investigations with ayahuasca have highlighted a psychotropic effect profile characterized by enhanced introspective attention, with individuals reporting altered somatic perceptions and intense emotional modifications, frequently accompanied by visual imagery. Despite recent advances in the study of ayahuasca pharmacology, the neural correlates of acute ayahuasca intoxication remain largely unknown. Objectives: To investigate the effects of ayahuasca administration on regional cerebral blood flow. Methods: Fifteen male volunteers with prior experience in the use of psychedelics received a single oral dose of encapsulated freeze-dried ayahuasca equivalent to 1.0 mg DMT/kg body weight and a placebo in a randomized double-blind clinical trial. Regional cerebral blood flow was measured 100-110 min after drug administration by means of single photon emission tomography (SPECT). Results: Ayahuasca administration led to significant activation of frontal and paralimbic brain regions. Increased blood perfusion was observed bilaterally in the anterior insula, with greater intensity in the right hemisphere, and in the anterior cingulate/frontomedial cortex of the right hemisphere, areas previously implicated in somatic awareness, subjective feeling states, and emotional arousal. Additional increases were observed in the left amygdala/parahippocampal gyrus, a structure also involved in emotional arousal. Conclusions: The present results suggest that ayahuasca interacts with neural systems that are central to interoception and emotional processing and point to a modulatory role of serotonergic neurotransmission in these processes.

Positron Emission Tomography (PET) is a significant advance in cancer imaging with great potential for optimizing radiation therapy (RT) treatment planning and thereby improving outcomes for patients. The use of PET and PET/CT in RT planning was

I t has been proposed that the ventricular myocardium, both right (RV) and left (LV), exists as a continuous muscle band. 1-4 The band is oriented spatially as a helix formed by basal and apical loops. We hypothesize that this unique anatomy and spatial configuration of the myocardial muscle determine the way the ventricular ejection and filling take place. 5,6 Further, knowledge of this unique morphologic and physiologic characteristic should facilitate development of more effective surgical procedures in congestive heart failure. Unwrapping of the Ventricular Myocardial Band Careful anatomic studies have established the way the cardiac band should be unrolled. 3,4 Unwrapping occurs easily (Figure 1), with least resistance, along a natural cleavage plane. Dissection of the ventricular myocardial band can be accomplished in three steps. In the first step (Figure 2, A), the basal loop is unrolled. The superficial fibers of the anterior aspect of the left ventricle are cut along the anterior interventricular sulcus (see arrow) to pull apart the RV free wall (Figure 2, B). Dissection can then proceed posteriorly following the cleavage plane. In this way the complete basal loop is extended in its full length (Figure 2, C, black and dark gray areas). In the second step (Figure 2, C and D), the aorta is dismounted, which involves separation along the cleavage plane (see arrow in Figure 2, C) defined by the two muscular strata, the fibers of the descending segment (white) and the fibers of the ascending

The aim of this study was to evaluate the physical performance of the Vereos whole-body PET/CT system according to the National Electrical Manufacturers Association (NEMA) NU2-2012 standard and to compare it with other state-of-the-art PET/CT systems. Methods: Spatial resolution, sensitivity, count-rate performance, count rate accuracy, and image quality were assessed. Specifically, spatial resolution was measured using an 18 F point-source. System sensitivity was calculated from acquisitions of an 18 F line source inside aluminum tubes of varying thickness. Assessment of count rate performance and count rate accuracy was based on measurements of an 18 F line source inside a 20-cm-diameter polyethylene cylinder. PET image quality was assessed using a NEMA IQ phantom. All measurements were performed according to the predefined and implemented NEMA NU2-2012 acquisition protocols at a clinical installation of a Vereos PET/CT system. Evaluation was performed using the software provided by the vendor. Results: The average (radial and tangential) transverse spatial resolution was 4.2, 4.5, and 5.5 mm in full width at half maximum for a 1-, 10-, and 20-cm radial offset, respectively, from the center of the field of view. Axial spatial resolution varied between 4.2 and 4.6 mm in full width at half maximum, depending on the radial source position. The average sensitivity was 5.2 cps/kBq. A peak noise-equivalent count (NEC) rate of 153.4 kcps was measured at an activity concentration of 54.9 kBq/mL. The scatter fraction at peak NEC rate was 33.9%, and the maximum count rate error at and below peak NEC rate was 6.8%. Contrast recovery coefficients varied from 54.3% (10-mm sphere) to 83.9% (22-mm sphere) for the hot spheres, and between 81.4% (28-mm sphere) and 87% (37-mm sphere) for the cold spheres for a given sphere-to-background ratio of 4:1. Conclusion: The overall performance characteristics of the Vereos PET/CT system are comparable to state-of-the-art wholebody PET/CT systems with the exception that the peak NEC rate occurs at a higher activity concentration, thus indicating the ability of the Vereos PET/CT system to cover a wider range of activities.

Cardiac sympathetic imaging with meta-iodobenzylguanidine (mIBG) is a noninvasive tool to risk stratify patients with heart failure (HF). In patients with ischemic and nonischemic cardiomyopathy, cardiac mIBG activity is a very powerful predictor of survival. Cardiac sympathetic imaging can help in understanding how sympathetic overactivity exerts its deleterious actions, which may result in better therapy and outcome for patients with HF.

Introduction The SPIN (Sant Pau Initiative on Neurodegeneration) cohort is a multimodal biomarker platform designed for neurodegenerative disease research following an integrative approach. Methods Participants of the SPIN cohort provide informed consent to donate blood and cerebrospinal fluid samples, receive detailed neurological and neuropsychological evaluations, and undergo a structural 3T brain MRI scan. A subset also undergoes other functional or imaging studies (video‐polysomnogram, 18F‐fluorodeoxyglucose PET, amyloid PET, Tau PET). Participants are followed annually for a minimum of 4 years, with repeated cerebrospinal fluid collection and imaging studies performed every other year, and brain donation is encouraged. Results The integration of clinical, neuropsychological, genetic, biochemical, imaging, and neuropathological information and the harmonization of protocols under the same umbrella allows the discovery and validation of key biomarkers across several neurodegenerative diseases. Discussion We describe our particular 10‐year experience and how different research projects were unified under an umbrella biomarker program, which might be of help to other research teams pursuing similar approaches.

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