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Objectives: We evaluated the cortical activity of 2 successful prelingually deafened adult cochlear implant (CI) users who have been trained by auditory-verbal/oral communication since childhood. Methods: Changes in regional cerebral blood flow were measured by positron emission tomography using 18F-fluorode-oxyglucose while the subjects were receiving auditory language stimuli by listening to a story. Ten normal-hearing volunteers were observed as age-matched control subjects. Results: In both cases, the auditory-related regions, when compared to same regions in the control subjects, showed hypermetabolism in the left dorsolateral prefrontal cortex and the left precentral gyrus--similar to that in successful CI users who are prelingually deafened children or postlingually deafened adults. Both subjects had the ability to activate these areas, and this ability might be one of the reasons that accounts for such exceptionally good performance in older prelingually deaf CI users. As for the visual-related regions, hypometabolism was observed in Brodmann areas 18 and 19, and this finding might be related to the intensive auditory-verbal/oral education that the subjects had received since childhood. Conclusions: Despite the limits imposed by the small sample size and the spatial resolution of positron emission tomography, this study yielded insights into the nature of the brain plasticity in prelingually deafened adults who are successful CI users. [ABSTRACT FROM AUTHOR]

In the USA , the stimulant drug methylphenidate (MPH) is used to treat a large number (2 million or more per year) of children with Attention Deficit Hyperactivity Disorder (ADHD). Although the US FDA approved MPH in the 1960s , the pharmacokinetic (PK) properties of serum concentrations of MPH in children with ADHD were not described until the 1980s, and then in only a few cases. Recently, information from drug development programs have increased our knowledge about the serum PK and some pharmacodynamic (PD) characteristics of MPH in ADHD children, and studies based on positron emission tomograpy (PET) in adult volunteers have provided new knowledge about the PK properties of MPH at the primary site of action in the brain. We will review these two topics and use this new information to evaluate the mechanisms of action of MPH. [Copyright &y& Elsevier]

For patients with locoregionally advanced nasopharyngeal carcinoma (NPC), radiotherapy, chemotherapy and even targeted therapy are widely accepted treatments. These treatments, although they mostly achieve locoregional tumor control, they may also be associated with complex post-treatment changes, such as edema, loss of tissue planes, fibrosis, mucositis and scarring, which may interfere with the detection of local recurrence and the response to therapy. However, timely detection is crucial for deciding whether treatment modification or discontinuation is required. This is the case report of a 51-year-old nasopharyngeal carcinoma patient with cervical nodal metastases (CNM). Following radiotherapy, chemotherapy and targeted therapy, multislice spiral enhanced computed tomography (CT), enhanced magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT of the neck were performed to compare the extent of the CNM. The enhanced CT and MRI images were unremarkable, whereas the 18F-FDG PET/CT images revealed the exact recurrence or remission. Therefore, 18F-FDG PET/CT exhibits a better sensitivity and specificity for evaluating the response to combined treatment compared to CT and/or MRI. [ABSTRACT FROM AUTHOR]

Merkel cell carcinoma is a rare type of neuroendocrine tumor of the skin with approximately 470 documented new cases annually in the United States. These tumors have high metastatic and recurrence rates, making them aggressive and difficult to treat. Diagnostic workup usually includes computed tomography, magnetic resonance imaging, and scintigraphy methods such as octreotide scans. More recently, positron emission tomographic scanning has been used to evaluate Merkel cell carcinomas. A case of Merkel cell carcinoma, in which positron emission tomography imaging with fluorodeoxyglucose played an important role in staging, re-staging, and identifying previously unknown distant metastatic disease, is presented in this article. [ABSTRACT FROM AUTHOR]

Purpose: We sought to address the impact of preoperative prostate specific membrane antigen (PSMA) positron emission tomography (PET) findings prior to radical prostatectomy and pelvic lymph node dissection on biochemical recurrence and time to adjuvant or salvage treatment., Materials and Methods: Between 2013 and 2017, 64 intermediate and 166 high risk (230) prostate cancer patients received 68 Ga-PSMA-11 PET followed by radical prostatectomy and pelvic lymph node dissection. Biochemical recurrence-free and therapy-free survivalwere determined. For all time-to-event analyses, univariable and multivariable Cox proportional hazards models and univariable Kaplan-Meier analyses were applied, with a significance threshold of p <0.05., Results: The overall sensitivity, specificity, positive predictive value and negative predictive value of PSMA PET for pN1 disease was 48.5%, 95.7%, 82.1% and 82.2%, respectively. Median followup was 30.2 months. Biochemical recurrence occurred in 50.4% (116) of patients and adjuvant or salvage treatment was performed in 46.5% (107). Worst biochemical recurrence-free and therapy-free survival was observed in pN1 patients who also exhibited PSMA PET positive lymph node, followed by pN1 patients without PSMA PET positive lymph node and patients without evidence of lymph node metastasis on histology and PSMA PET (median biochemical recurrence-free survival 1.7 vs. 7.5 vs. >36 months, median therapy-free survival 2.6 vs. 8.9 vs. >36 months)., Conclusions: Patients with positive lymph node on PSMA PET prior to radical prostatectomy have to expect early biochemical recurrence and adjuvant/salvage therapy, despite thorough pelvic lymph node dissection. Therefore, results from PSMA PET can be used for patients' consultation and more stringent followup as well as for planning of neoadjuvant/adjuvant therapy.

Aiming the faster development from bench to bedside of new potential tracers, multimodal tracers for positron emission tomography (PET) and optical imaging (OI) have emerged as a very promising tool. Indeed, they combine the simplicity of use of optical techniques for in vitro / in vivo pre-clinical studies with the various clinical possibilities offered by PET imaging using their radioactive versions. In this context, the preparation of new tags detectable by fluorescence imaging and potentially suitable for PET imaging after a last-step 11C-labeling of the corresponding precursor has been investigated. Various designs and syntheses were explored by linking o -iodobenzyl alcohols and tetramethyl-BODIPY moieties together. Among them, the most promising structure was produced in 30% yield over five steps from a commercially available and inexpensive starting material. Image 1 • Design and synthesis of a promising o -iodobenzyl alcohol-BODIPY tag for multimodal imaging (fluorescence / 11C-labeling). [ABSTRACT FROM AUTHOR]

Dang and colleagues recently reported in the journal that tumor response to definitive chemoradiation, as assessed using the RECIST criteria, and the risk of radiation pneumonitis were positively correlated in patients with non-small cell lung cancer (NSCLC). We had previously reported similar findings in a study that used positron tomography both to measure tumor response and to assess normal tissue toxicity in patients treated with chemoradiation for NSCLC. Taken together these reports suggest that radiosensitivity of normal tissues and tumors may be strongly linked in a proportion of patients with lung cancer. [ABSTRACT FROM AUTHOR]

For patients with locoregionally advanced nasopharyngeal carcinoma (NPC), radiotherapy, chemotherapy and even targeted therapy are widely accepted treatments. These treatments, although they mostly achieve locoregional tumor control, they may also be associated with complex post-treatment changes, such as edema, loss of tissue planes, fibrosis, mucositis and scarring, which may interfere with the detection of local recurrence and the response to therapy. However, timely detection is crucial for deciding whether treatment modification or discontinuation is required. This is the case report of A 51-year-old nasopharyngeal carcinoma patient with cervical nodal metastases (CNM). Following radiotherapy, chemotherapy and targeted therapy, multislice spiral enhanced computed tomography (CT), enhanced magnetic resonance imaging (MRI) and 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT of the neck were performed to compare the extent of the CNM. The enhanced CT and MRI images were unremarkable, whereas the 18 F-FDG PET/CT images revealed the exact recurrence or remission. Therefore, 18 F-FDG PET/CT exhibits a better sensitivity and specificity for evaluating the response to combined treatment compared to CT and/or MRI.