Hypermetabolism on Pediatric PET Scans of Brain Glucose Metabolism: What Does It Signify?

Abstract

When interpreting clinical 2-deoxy-2[ 18 F]fluoro-D-glucose (18F-FDG) positron emission tomography (PET) scans of the brain (excluding tumors) in children, the typical abnormality is hypometabolism of various brain regions. Focal areas of hypermetabolism are noted occasionally and the usual interpretation is that the hypermetabolic region represents a seizure focus. In this review, we discuss and illustrate the multiple causes of hypermetabolism that should not be interpreted as seizure activity could potentially lead to an incorrect interpretation of 18F-FDG PET studies. Various causes or conditions where focal hypermetabolism can be encountered on 18F-FDG PET studies include interictal hypermetabolism, Sturge-Weber syndrome, changes associated with brain plasticity following injury, Rett syndrome, hypoxicischemic brain injury, various inborn errors of metabolism, and autoimmune encephalitis. The radiologist or nuclear medicine physician interpreting clinical 18F-FDG PET studies should be aware of these circumstances to provide accurate assessment of the study.

Evidence of brain metabolism redistribution from neocortex to primitive brain structures in early acute COVID-19 respiratory syndrome

“…The high concentration of mitochondria in basal ganglia neurons predisposes them to ischemic damage [ 22 ]. It has been already demonstrated that basal ganglia and thalami may be particularly affected by hypoxia in children and neonates [ 23 , 24 ]. In both children and adults, hypoxic-ischemic encephalopathy almost invariably causes bilateral and symmetrical damage, often affecting the basal ganglia [ 25 ], as observed in our patients with COVID-19.…”

Flares of Confusion: A Case Report of Uterine Leiomyoma and Angiomatosis Complexity on Imaging

“…Typically, leiomyomas attain moderate levels of [ 18 F]FDG uptake [17]. Angiomatosis, on the other hand, has been studied at other body locations and has been shown to demonstrate moderate [ 18 F]FDG expression [6][7][8][9]. The causal factor for such intense [ 18 F]FDG activity seems to be the metabolic potentiation effect of leiomyoma on the basis of the background of angiomatosis, giving rise to high [ 18 F]FDG uptake derived from the combination of both benign tumors potentiating [ 18 F]FDG expression.…”

“…In general, angiomatosis is not limited to a specific anatomical location but rather can present in various regions of the human body [6][7][8][9]. Within the female genital tract, this particular condition can manifest as discrete lesions, occur alongside other hemangiomas affecting the skin or other organs, or be a constituent of intricate syndromes such as the Klippel-Trénaunay-Weber syndrome [10].…”