During the current nascent pandemic, anosmia has been increasingly reported among patients with coronavirus disease-2019 (COVID-19) (1). While postviral olfactory loss secondary to nasal congestion or conductive pathway alteration is a known sequela of sinonasal viral infections (2), anosmia of COVID-19 is less commonly associated with rhinorrhea or nasal congestion (3). This may indicate sensory neural loss as the underlying cause of the olfactory dysfunction rather than the conductive mechanism in most cases of postviral olfactory loss. We have recently reported normal morphology of the olfactory bulb on magnetic resonance imaging in anosmia of COVID-19 (4). Whether there is decreased neural activity in olfactory pathways despite normal morphology is unknown. We sought to assess the neural metabolic activity in anosmia of COVID-19 by 18fluoro-2-deoxy-d-glucose (18FDG) positron emission tomographyÀcomputed tomography (PET-CT). We included a 27-year-old healthy, right-handed woman, diagnosed with COVID-19 by polymerase chain reaction assay. The patient had persistent isolated anosmia for 6 weeks. She had no history of alcohol intake or tobacco smoking and no background of psychiatric problems. The patient was asked to fast for 6 hours prior to imaging. We performed 18FDG-PET/CT in a neutral environment using 5 ml of aerosolized 0.9% NaCl delivered with O 2 at 3.5 ml/min via facial mask for 9 minutes. The patient was instructed to breath normally without sniffing. After 3 minutes, the patient received intravenous 18FDG (4.6 Megabecquerel/kg, Masih Daneshvari Hospital, Tehran), and the neutral olfactory condition continued for another 6 minutes. The patient laid down in a semi-darkened,

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Dear Editor-While fever, cough, and dyspnea are the main symptoms of coronavirus disease-2019 (COVID-19), nonrespiratory presentations have been increasingly recognized, including neurological manifestations (1-3). Herein, we describe the first report of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced facial nerve palsy assessed by 18 fluoro-2-deoxy-d-glucose (18 FDG) positron emission tomography-computed tomography (PET/CT). A 60-year-old healthy man with COVID-19, confirmed by polymerase chain reaction assay performed due to close contact with a COVID-19 case, developed sudden-onset right-sided facial nerve palsy. The patient had no systemic, respiratory, or auditory symptoms, nor facial pain. He was subsequently admitted with fever, cough, and dyspnea, and received remdesivir, dexamethasone, and oxygen. There was peripheral right-sided facial nerve palsy, involving mouth, eye, and forehead, consistent with Bell's palsy. Electromyography revealed decreased compound muscle action potential (»60% axonal degeneration) in the right facial nerve. Given the likelihood of neuropathic impact of SARS-CoV-2(3), we performed 18 FDG-PET/CT to assess the metabolic activity of the facial nerve and the related processing neurons. The study was approved by the Institutional Review Board of our institution and the patient provided written consent.