BACKGROUND AND PURPOSE: Anosmia or hyposmia, often accompanied by changes in taste, is recognized as a common symptom that can assist in the diagnosis of coronavirus disease 2019 (COVID-19). The pathogenesis of olfactory dysfunction in COVID-19 is not yet fully understood. MR imaging represents a useful anatomic imaging method for the evaluation of olfactory dysfunction associated with varying etiologies, including viral infection, trauma, and neurodegenerative processes. This case-control study was conducted to compare quantitative measurements of olfactory anatomic structures between patients diagnosed with COVID-19 associated with persistent olfactory dysfunction and healthy controls. MATERIALS AND METHODS: This study has a retrospective design. Cranial MR imaging was performed on all participants in both the patient and control groups. The bilateral olfactory bulb volume, olfactory tract length, and olfactory sulcus depth were measured in all patients. RESULTS: A total of 116 people aged 18–60 years, including 36 patients diagnosed with COVID-19 and 80 controls, were included in the study. All measured values were compared between the patient and control groups. The right, left, and total olfactory bulb volume values were significantly lower in the patient group than in the control group. The patient group also had significantly lower right and left olfactory sulcus depth and olfactory tract length values compared with those in the control group. CONCLUSIONS: MR imaging findings can be used to demonstrate olfactory injury in patients with COVID-19. The olfactory pathway may represent an alternative route for virus entry into the central nervous system.

Background: The aim of this study was to determine the normal reference values for olfactory sulcus depth (OSd), olfactory tract length (OTl) and olfactory bulb volume (OBv) in the pediatric population with routine magnetic resonance imaging (MRI) and determine the relationship, if any, between these values and patient sex and age. Materials and methods: Ninety patients with a median age of 8 years (age range: 3-17 years), consisting of 45 males and 45 females with normal brain MRI scans were evaluated. The patients were divided into three subgroups based on age range, with n=30 per subgroup; Group 1: Young children (3-6 years), Group 2: Children (7-11 years) and Group 3: Adolescents (12-17 years). In the cranial MRI examination of all groups, the right, left and total olfactory bulb volume values were measured in mm³, the right and left olfactory tract length values and the right and left olfactory sulcus depth values were calculated manually in mm. Demographic data including sex and age were recorded. Results: There was no significant difference between the age groups in terms of sex. Right-left olfactory sulcus depth; right-left olfactory tract length and right-left total olfactory bulb volume values increased significantly when they are compared in terms of age groups (p < 0.0001, 0.028; <0.0001, <0.0001; <0.0001, <0.0001; < 0.0001, respectively). There was no significant difference between right and left olfactory tract length and olfactory bulb volumes in all groups (p = 0.792 and p = 0.478), but the right olfactory sulcus depth was significantly larger than the left (p = 0.003). Conclusions: Olfactory tract length and olfactory bulb volume dimensions of olfactory nerve and olfactory sulcus depth should be checked during diagnosis of respective illnesses in pediatric population especially increasing age. Background: The aim of this study was to determine the normal reference values for olfactory sulcus depth (OSd), olfactory tract length (OTl) and olfactory bulb volume (OBv) in the pediatric population with routine magnetic resonance imaging (MRI) and determine the relationship, if any, between these values and patient sex and age. Materials and methods: Ninety patients with a median age of 8 years (age range: 3-17 years), consisting of 45 males and 45 females with normal brain MRI scans were evaluated. The patients were divided into three subgroups based on age range, with n=30 per subgroup; Group 1: Young children (3-6 years), Group 2: Children (7-11 years) and Group 3: Adolescents (12-17 years). In the cranial MRI examination of all groups, the right, left and total olfactory bulb volume values were measured in mm³, the right and left olfactory tract length values and the right and left olfactory sulcus depth values were calculated manually in mm. Demographic data including sex and age were recorded. Results: There was no significant difference between the age groups in terms of sex. Right-left olfactory sulcus depth; right-left olfactory tract length and right-left total olfactory bulb volume values increased significantly when they are compared in terms of age groups (p < 0.0001, 0.028; <0.0001, <0.0001; <0.0001, <0.0001; < 0.0001, respectively). There was no significant difference between right and left olfactory tract length and olfactory bulb volumes in all groups (p = 0.792 and p = 0.478), but the right olfactory sulcus depth was significantly larger than the left (p = 0.003). Conclusions: Olfactory tract length and olfactory bulb volume dimensions of olfactory nerve and olfactory sulcus depth should be checked during diagnosis of respective illnesses in pediatric population especially increasing age.

This study aimed to determine pain characteristics in patients with persistent headache after COVID-19 and to investigate the role of increased intracranial pressure (ICP) in the pathogenesis of this headache. This is a case-control study comparing the parameters and measurements indicating increased ICP based on magnetic resonance imaging between COVID-19–diagnosed patients with persistent headache and a control group. Optic nerve sheath diameter (ONSD) and eyeball transverse diameter (ETD) were performed on the left eye of each participant. Seventeen of the patients (53.12%) met the diagnostic criteria for new daily persistent headache. Seven patients (21.87%) had migraine, and eight (25%) had tension headache characteristics. No significant difference was observed between the patient and control groups in terms of the ONSD and ETD values. It is possible that the etiopathogenesis is multifactorial. We consider that future studies that will evaluate ICP measurements in large patient groups can present a different perspective for this subject.