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Mastoid opacification grades. Axial CT scan images demonstrate normally aerated, partially opacified left greater than right mastoid air cells and bilateral completely opacified mastoid air cells in images A, B, and C respectively.
Source publication
Background:
Acute neurological sequela in patients with COVID-19 infection include acute thromboembolic infarcts related to cytokine storm and post infectious immune activation resulting in a prothrombotic state. Radiologic imaging studies of the sinonasal tract and mastoid cavity in patients with COVID-19 infection are sparse and limited to case...
Context in source publication
Citations
... Researchers have been studying the phenomenon, including its pathogeny, symptoms, duration, and recovery. Evidence implies characteristics unique from the obstructive etiology of the olfactory impairment in other viral upper respiratory tract infections, since there is a decreased incidence of sinonasal symptoms in COVID-19 associated olfactory impairment, while the pathogenesis of COVID-19 anosmia is still under question [7,8]. Olfactory recess obstruction/inflammation and/or olfactory bulb injury are suggested causes of COVID-19 anosmia [9]. ...
Background:
Olfactory impairment is a major symptom of COVID-19. Is it necessary for COVID-19 patients to perform the detection of olfactory function, even how to select the olfactory psychophysical assessment tool.
Methods:
Patients infected with SARS-CoV-2 Delta variant were firstly taken into three categories (mild, moderate, and severe) according to the clinical classification. The Odor Stick Identification Test for the Japanese (OSIT-J) and the Simple Olfactory Test were used to assess olfactory function. Moreover, these patients were divided into three groups based on the results of the olfactory degree (euosmia, hyposmia, and dysosmia), too. The statistical analysis of the correlations between olfaction and clinical characteristics of patients were performed.
Results:
Our study demonstrated that the elderly men of Han were more susceptible to infected SARS-CoV-2, the clinical symptoms of the COVID-19 patients showed a clear correspondence with the disease type and the degree of olfactory disturbance. Whether or not to vaccinate and whether to complete the whole course of vaccination was closely related to the patient's condition. OSIT-J Test and Simple Test were consistent in our work, indicating that olfactory grading would worsen with the aggravation of symptoms. Furthermore, the OSIT-J method maybe better than Simple Olfactory Test.
Conclusion:
The vaccination has an important protective effect on the general population, and vaccination should be vigorously promoted. Moreover, it is necessary for COVID-19 patients to perform the detection of olfactory function, and the easier, faster and less expensive method for determination of olfactory function should be utilized to COVID-19 patients as the vital physical examination.
... Marginally lower rates of sinus and mastoid opacification in patients with Covid-19 are reported in the literature ( Table 6); 25-30 41.8 per cent of Moonis and colleagues' cohort of 55 patients had sinus disease, yet only 7 per cent demonstrated mastoid opacification. 29 Similarly, İslamoğlu et al. reported much lower levels of mastoid opacification in a cohort of 129 patients, at only 2.32 per cent. 30 Our results reflect higher levels of sinus opacification in patients with Covid-19 when compared with a 14.8-37 per cent rate of incidental prevalence of sinus opacification on CT prior to the SARS-CoV-2 pandemic. ...
... Similarly, ethmoidal, maxillary and sphenoid sinuses were most commonly affected in Moonis and colleagues' cohort. 29 Although the nasopharynx has been demonstrated to host high titres of SARS-CoV-2, 9,10 literature suggests this is not reflected in radiological findings. 29,30 Moonis et al. further demonstrated that olfactory cleft opacification and nasopharyngeal thickness did not correlate with Covid-19 infection. ...
... 29 Although the nasopharynx has been demonstrated to host high titres of SARS-CoV-2, 9,10 literature suggests this is not reflected in radiological findings. 29,30 Moonis et al. further demonstrated that olfactory cleft opacification and nasopharyngeal thickness did not correlate with Covid-19 infection. 29 Such limited sinonasal involvement does not reflect radiological findings reported for other viral upper respiratory tract infections. ...
Objective
To assess the incidence of radiological inflammation within the paranasal sinuses, middle ear and mastoid in patients with confirmed severe acute respiratory syndrome coronavirus-2.
Methods
A retrospective cohort study was conducted to examine consecutive adults (aged over 18 years) with coronavirus disease 2019 (confirmed on polymerase chain reaction within 7 days of imaging) who underwent computed tomography of the head between 1 March 2020 and 24 June 2020. Lund–Mackay and mastoid and middle-ear opacification scores were used to categorise the extent of sinus and mastoid opacification on axial and coronal computed tomography images.
Results
Of 147 patients originally identified, only 83 met the inclusion criteria. Sinus opacification was present in 51.8 per cent of patients ( n = 43), and middle-ear or mastoid opacification was observed in 24.1 per cent ( n = 20). There was no statistically significant difference in sinus or middle-ear and mastoid opacification between patients after stratification based on 30-day all-cause mortality.
Conclusion
Radiological computed tomography findings suggest mild mucosal disease within the sinuses, middle ear and mastoid. There was no statistical correlation between such opacification and 30-day mortality.
... 73 Nonetheless, a radiological study (N = 55) found that few normosmic COVID-19 showed significant nasopharyngeal thickness (7%) or olfactory cleft opacification (7%) on CT or MRI. 74 With substantial heterogeneity in current studies, extensive analysis of olfactory imaging findings in a significant population of COVID-19 normosmic patients is required. Furthermore, there was significant between-study heterogeneity in terms of imaging protocols. ...
Objective:
Olfactory dysfunction (OD) is a common presenting symptom of COVID-19 infection. Radiological imaging of the olfactory structures in patients with COVID-19 and OD can potentially shed light on its pathogenesis, and guide clinicians in prognostication and intervention.
Methods:
PubMed, Embase, Cochrane, SCOPUS were searched from inception to August 1, 2021. Three reviewers selected observational studies, case series, and case reports reporting radiological changes in the olfactory structures, detected on magnetic resonance imaging, computed tomography, or other imaging modalities, in patients aged ≥18 years with COVID-19 infection and OD, following preferred reporting items for systematic reviews and meta-analyses guidelines and a PROSPERO-registered protocol (CRD42021275211). We described the proportion of radiological outcomes, and used random-effects meta-analyses to pool the prevalence of olfactory cleft opacification, olfactory bulb signal abnormalities, and olfactory mucosa abnormalities in patients with and without COVID-19-associated OD.
Results:
We included 7 case-control studies (N = 353), 11 case series (N = 154), and 12 case reports (N = 12). The pooled prevalence of olfactory cleft opacification in patients with COVID-19 infection and OD (63%, 95% CI = 0.38-0.82) was significantly higher than that in controls (4%, 95% CI = 0.01-0.13). Conversely, similar proportions of cases and controls demonstrated olfactory bulb signal abnormalities (88% and 94%) and olfactory mucosa abnormalities (2% and 0%). Descriptive analysis found that 55.6% and 43.5% of patients with COVID-19 infection and OD had morphological abnormalities of the olfactory bulb and olfactory nerve, respectively, while 60.0% had abnormal olfactory bulb volumes.
Conclusion:
Our findings implicate a conductive mechanism of OD, localized to the olfactory cleft, in approximately half of the affected COVID-19 patients. Laryngoscope, 2022.
... Upper respiratory tract infections account as 1 of the most common identifiable cause of OD, with postinfectious cases constituting 22%-36% of all olfactory loss cases (9,10). The pathogenesis of COVID-19 anosmia is still debated, however evidence suggests features distinct from the obstructive etiology of the OD in other viral upper respiratory tract infections, as there is a lower prevalence of sinonasal symptoms in COVID-19 related OD (1,11). Proposed mechanisms for COVID-19 anosmia are olfactory recess obstruction/inflammation and/or olfactory bulb damage (12). ...
Objective
: To evaluate how COVID-19 anosmia imaging findings resembled and differed from post-infectious olfactory dysfunction (OD).
Material and Methods
: A total of 31 patients presenting with persistent COVID-19 related OD and 97 patients with post-infectious OD were included. Olfactory bulb MRI, DTI and olfactory fMRI findings in both groups were retrospectively assessed.
Results
: All COVID-19 related OD cases were anosmic, 18.6% of post-infectious OD patients were hyposmic and remaining 81.4% were anosmic. Mean interval between onset of OD and imaging was 1.5 months for COVID-19 related OD and 6 months for post-infectious OD.
Olfactory bulb volumes were significantly higher in COVID-19 related OD than post-infectious OD. Deformed bulb morphology and increased olfactory bulb signal intensity was seen in 58.1% and 51.6% with COVID-19 related OD; and 63.9% and 46.4% with post-infectious OD; without significant difference. Significantly higher rate of olfactory nerve clumping and higher QA values at orbitofrontal and entorhinal regions were observed in COVID-19 related OD than post-infectious OD.
Absence of orbitofrontal and entorhinal activity showed no statistically significant difference between COVID-19 related OD and post-infectious OD, however trigeminosensory activity was more robust in COVID-19 related OD cases.
Conclusion
: Olfactory bulb damage may play a central role in persistent COVID-19 related anosmia. Though there is decreased olfactory bulb volume and decreased white matter tract integrity of olfactory regions in COVID-19 related anosmia, this is not as pronounced as in other post-infectious OD. Trigeminosensory activity was more robust in COVID-19 related OD. These findings may reflect better preserved central olfactory system in COVID-19 related OD compared to COVID-19 related OD.
The maxillary sinus aeration using the computational fluid dynamics (CFD) method based on individual adult patients’ computed tomography (CT) scans were analyzed. The analysis was based on CT images of 4 patients: one with normal nose anatomy and three with nasal septal deviation (NSD) and concha bullosa (CB). The CFD simulation was performed using the Reynolds-Average Simulation approach and turbulence closure based on linear eddy viscosity supplemented with the two-equation k-ω SST model. As a result, it was found that the lower part of NSD has the most significant impact on the airflow change within the maxillary sinuses compared to CB and the upper part of NSD. In a healthy nose, the airflow in the sinuses is continuous, while NSD and CB change this flow into pulsatile. Multiple changes in the direction of flow during one respiratory phase were observed. The flow intensity within the maxillary sinus opening is lower on the NSD side. The concept of vorticity measure is introduced to evaluate and compare various patients qualitatively. Typically, the lowest values of such measures are obtained for healthy airways and the highest for pathological changes in the nasal cavity.
