Haifeng Hou

PET imaging reveals brain functional changes in internet gaming disorder

BackgroundInternet gaming disorder is an increasing problem worldwide, resulting in critical academic, social, and occupational impairment. However, the neurobiological mechanism of internet gaming disorder remains unknown. The aim of this study is to assess brain dopamine D2 (D2)/Serotonin 2A (5-HT2A) receptor function and glucose metabolism in the same subjects by positron emission tomography (PET) imaging approach, and investigate whether the correlation exists between D2 receptor and glucose metabolism.MethodsTwelve drug-naive adult males who met criteria for internet gaming disorder and 14 matched controls were studied with PET and 11C-N-methylspiperone (11C-NMSP) to assess the availability of D2/5-HT2A receptors and with 18F-fluoro-D-glucose (18F-FDG) to assess regional brain glucose metabolism, a marker of brain function. 11C-NMSP and 18F-FDG PET imaging data were acquired in the same individuals under both resting and internet gaming task states.ResultsIn internet gaming disorder subjects, a significant decrease in glucose metabolism was observed in the prefrontal, temporal, and limbic systems. Dysregulation of D2 receptors was observed in the striatum, and was correlated to years of overuse. A low level of D2 receptors in the striatum was significantly associated with decreased glucose metabolism in the orbitofrontal cortex.ConclusionsFor the first time, we report the evidence that D2 receptor level is significantly associated with glucose metabolism in the same individuals with internet gaming disorder, which indicates that D2/5-HT2A receptor-mediated dysregulation of the orbitofrontal cortex could underlie a mechanism for loss of control and compulsive behavior in internet gaming disorder subjects.

Positron Emission Tomography Molecular Imaging of Dopaminergic System in Drug Addiction

Dopamine (DA) is involved in drug reinforcement, but its role in drug addiction remains unclear. Positron emission tomography (PET) is the first technology used for the direct measurement of components of the dopaminergic system in the living human brain. In this article, we reviewed the major findings of PET imaging studies on the involvement of DA in drug addiction, especially in heroin addiction. Furthermore, we summarized PET radiotracers that have been used to study the role of DA in drug addiction. To investigate presynaptic function in drug addiction, PET tracers have been developed to measure DA synthesis and transport. For the investigation of postsynaptic function, several radioligands targeting dopamine one (D1) receptor and dopamine two (D2) receptor are extensively used in PET imaging studies. Moreover, we also summarized the PET imaging findings of heroin addiction studies, including heroin‐induced DA increases and the reinforcement, role of DA in the long‐term effects of heroin abuse, DA and vulnerability to heroin abuse and the treatment implications. PET imaging studies have corroborated the role of DA in drug addiction and increase our understanding the mechanism of drug addiction. Anat Rec, 2012.

Multiple metastasis-like bone lesions in scintigraphic imaging.

Multiple benign osteolytic lesions are very hard to differentiate from disseminated bone metastasis. Whole-body bone scintigraphy (WBBS) with technetium-99m methylene diphosphonate (Tc-99m MDP) demonstrates multiple lesions with increased uptake in any bone involved. Even combined with medical history and multiple imaging results, such as MRI and CT, the clinical diagnosis of metastasis lesion remains as a challenge. These clinical characteristics are similar to multiple malignant bone metastases and therefore affect the following treatment procedures. In this paper, we analyzed multiple benign osteolytic lesions, like eosinophilic granuloma (EG), multiple myeloma (MM), disseminated tuberculosis, fibrous dysplasia, or enchondroma, occurring in our daily clinical work and concluded that additional attention should be paid before giving the diagnosis of multiple bone metastases.

The Diagnostic Value of 18F-FDG PET/CT in Association with Serum Tumor Marker Assays in Breast Cancer Recurrence and Metastasis

Background. After initial treatment of breast cancer (BC), monitoring locoregional recurrence and distant metastases is a great clinical challenge. Objective. To evaluate the efficacy of PET/CT in association with serum tumor makers in BC follow-up. Methods. Twenty-six women with a history of modified radical mastectomy were evaluated by 18F-FDG PET/CT. The results of PET/CT were compared with those of conventional imaging techniques (CITs) (including mammography, chest radiography, CT, MRI, ultrasound, and bone scintigraphy). Serum tumor markers of CEA, CA 125, and CA 15-3 in the BC patients were also analyzed in association with the results of PET/CT. Results. Compared with CITs, PET/CT was more sensitive to detect the malignant foci and had better patient-based sensitivity and specificity. The mean CA 15-3 serum level was significantly higher in the confirmed positive patients of PET/CT results than in the confirmed negative ones, while there were no significant differences in the serum levels of CEA and CA 125 of both groups. Conclusion. PET/CT is a highly efficient tool for BC follow-up compared with CITs. The high serum levels of CA 15-3 in confirmed positive PET/CT patients indicated the clinical value of CA 15-3 in BC follow-up.

Glucose Metabolic Profile by Visual Assessment Combined with SPM Analysis in Pediatric Patients with Epilepsy

PET with 18F-FDG has been used for presurgical localization of epileptogenic foci; however, in nonsurgical patients, the correlation between cerebral glucose metabolism and clinical severity has not been fully understood. The aim of this study was to evaluate the glucose metabolic profile using 18F-FDG PET/CT imaging in patients with epilepsy. Methods: One hundred pediatric epilepsy patients who underwent 18F-FDG PET/CT, MRI, and electroencephalography examinations were included. Fifteen age-matched controls were also included. 18F-FDG PET images were analyzed by visual assessment combined with statistical parametric mapping (SPM) analysis. The absolute asymmetry index (|AI|) was calculated in patients with regional abnormal glucose metabolism. Results: Visual assessment combined with SPM analysis of 18F-FDG PET images detected more patients with abnormal glucose metabolism than visual assessment only. The |AI| significantly positively correlated with seizure frequency (P < 0.01) but negatively correlated with the time since last seizure (P < 0.01) in patients with abnormal glucose metabolism. The only significant contributing variable to the |AI| was the time since last seizure, in patients both with hypometabolism (P = 0.001) and with hypermetabolism (P = 0.005). For patients with either hypometabolism (P < 0.01) or hypermetabolism (P = 0.209), higher |AI| values were found in those with drug resistance than with seizure remission. In the post-1-y follow-up PET studies, a significant change of |AI| (%) was found in patients with clinical improvement compared with those with persistence or progression (P < 0.01). Conclusion: 18F-FDG PET imaging with visual assessment combined with SPM analysis could provide cerebral glucose metabolic profiles in nonsurgical epilepsy patients. |AI| might be used for evaluation of clinical severity and progress in these patients. Patients with a prolonged period of seizure freedom may have more subtle (or no) metabolic abnormalities on PET. The clinical value of PET might be enhanced by timing the scan closer to clinical seizures.

Neural correlates of the popular music phenomenon: evidence from functional MRI and PET imaging

PurposeMusic can induce different emotions. However, its neural mechanism remains unknown. The aim of this study was to use functional magnetic resonance imaging (fMRI) and position emission tomography (PET) imaging for mapping of neural changes under the most popular music in healthy volunteers.MethodsBlood-oxygen-level-dependent (BOLD) fMRI and monoamine receptor PET imaging with 11C-N-methylspiperone (11C-NMSP) were conducted under the popular music Gangnam Style and light music A Comme Amour in healthy subjects. PET and fMRI images were analyzed by using the Statistical Parametric Mapping software (SPM).ResultsSignificantly increased fMRI BOLD signals were found in the bilateral superior temporal cortices, left cerebellum, left putamen and right thalamus cortex. Monoamine receptor availability was increased significantly in the left superior temporal gyrus and left putamen, but decreased in the bilateral superior occipital cortices under the Gangnam Style compared with the light music condition. Significant positive correlation was found between 11C-NMSP binding and fMRI BOLD signals in the left temporal cortex. Furthermore, increased 11C-NMSP binding in the left putamen was positively correlated with the mood arousal level score under the Gangnam Style condition.ConclusionPopular music Gangnam Style can arouse pleasure experience and strong emotional response. The left putamen is positively correlated with the mood arousal level score under the Gangnam Style condition. Our results revealed characteristic patterns of brain activity associated with Gangnam Style, and may also provide more general insights into the music-induced emotional processing.

PET Imaging Reveals Brain Metabolic Changes in Adolescent Rats Following Chronic Escalating Morphine Administration

PurposeNon-medical use of prescription opioids, especially among adolescents, has been substantially increased in recent years. However, the neuromechanism remains largely unexplored. In the present study, we aimed to investigate the brain metabolic changes in adolescent rats following chronic escalating morphine administration using positron emission tomography (PET).Procedures2-Deoxy-2-[18F]Fluoro-d-glucose ([18F]FDG) microPET imaging was performed, and statistical parametric mapping (SPM) was used for image analysis. Glucose transporter 3 (Glut-3), dopamine D2 receptor (D2R), and Mμ-opioid receptor (μ-OR) were used for immunostaining analysis.ResultsCerebral glucose metabolism was increased in the corpus callosum (CC) and right retrosplenial dysgranular cortex (rRSD), while it was decreased in the right ventral pallidum (rVP). The expressions of Glut-3, D2R, and μ-OR were increased in CC and rRSD, while they were decreased in rVP. Furthermore, glucose metabolism and Glut-3 expression were positively correlated with the expressions of D2R or μ-OR in CC, rRSD, and rVP.Conclusions[18F]FDG microPET brain imaging study in combination with immunohistological investigation revealed that CC, rRSD, and rVP were specifically involved in opioid dependence in adolescents. Our findings provided valuable insights into the neuromechanism of adolescent addiction of prescription opioids and might have important implications for the development of prevention and intervention approaches.

Alteration of monoamine receptor activity and glucose metabolism in paediatric patients with anticonvulsant-induced cognitive impairment

A landmark study from the Institute of Medicine reported that the assessment of cognitive difficulties in children with epilepsy is timely and imperative. Anticonvulsant-induced cognitive impairment could influence the quality of life more than seizure itself in patients. Although the monoaminergic system is involved in the regulation of cognitive process, its role in anticonvulsant-induced cognitive impairment remains unclear. Methods: To explore in vivo monoamine receptor binding activity in patients with anticonvulsant-induced cognitive impairment, each patient underwent PET imaging with both monoamine receptor binding agent 11C-N-methylspiperone and glucose metabolic agent 18F-FDG. Tests of intelligence quotient (IQ), including verbal IQ (VIQ), performance IQ (PIQ), and full-scale IQ (FSIQ), were performed in each patient. Results: Compared with the patients with monotherapy, patients with polytherapy had significantly lower VIQ, PIQ, and FSIQ (P < 0.01 in each comparison), as well as significantly lower monoamine receptor activities detected in the caudate nucleus, prefrontal cortex, dorsal anterior cingulate cortex, and amygdale (P < 0.05 in each comparison). However, regarding the glucose metabolism, there was no significant difference found in patients with monotherapy or polytherapy (P > 0.05). Conclusion: Monoamine receptor PET imaging could be a promising in vivo imaging biomarker for mapping anticonvulsant-induced cognitive impairment.