Functional connectivity patterns in parosmia.

OBJECTIVE: Parosmia is a qualitative olfactory dysfunction presenting as "distorted odor perception" in presence of an odor source. Aim of this study was to use resting state functional connectivity to gain more information on the alteration of olfactory processing at the level of the central nervous system level. METHODS: A cross sectional study was performed in 145 patients with parosmia (age range 20-76 years; 90 women). Presence and degree of parosmia was diagnosed on the basis of standardized questionnaires. Participants also received olfactory testing using the "Sniffin' Sticks". Then they underwent resting state scans using a 3 T magnetic resonance imaging scanner while fixating on a cross. RESULTS: Whole brain analyses revealed reduced functional connectivity in salience as well as executive control networks. Region of interest-based analyses also supported reduced functional connectivity measures between primary and secondary olfactory eloquent areas (temporal pole, supramarginal gyrus and right orbitofrontal cortex; dorso-lateral pre-frontal cortex and the right piriform cortex). CONCLUSIONS: Participants with parosmia exhibited a reduced information flow between memory, decision making centers, and primary and secondary olfactory areas.

ChatGPT-assisted deep learning model for thyroid nodule analysis: beyond artifical intelligence.

AIMS: To develop a deep learning model, with the aid of ChatGPT, for thyroid nodules, utilizing ultrasound images. The cytopathology of the fine needle aspiration biopsy (FNAB) serves as the baseline. MATERIAL AND METHODS: After securing IRB approval, a retrospective study was conducted, analyzing thyroid ultrasound images and FNAB results from 1,061 patients between January 2017 and January 2022. Detailed examinations of their demographic profiles, imaging characteristics, and cytological features were conducted. The images were used for training a deep learning model to identify various thyroid pathologies. ChatGPT assisted in developing this model by aiding in code writing, preprocessing, model optimization, and troubleshooting. RESULTS: The model demonstrated an accuracy of 0.81 on the testing set, within a 95% confidence interval of 0.76 to 0.87. It presented remarkable results across thyroid subgroups, particularly in the benign category, with high precision (0.78) and recall (0.96), yielding a balanced F1-score of 0.86. The malignant category also displayed high precision (0.82) and recall (0.92), with an F1-score of 0.87. CONCLUSIONS: The study demonstrates the potential of artificial intelligence, particularly ChatGPT, in aiding the creation of robust deep learning models for medical image analysis.

Deep learning for assessing image quality in bi-parametric prostate MRI: A feasibility study.

BACKGROUND: Although systems such as Prostate Imaging Quality (PI-QUAL) have been proposed for quality assessment, visual evaluations by human readers remain somewhat inconsistent, particularly among less-experienced readers. OBJECTIVES: To assess the feasibility of deep learning (DL) for the automated assessment of image quality in bi-parametric MRI scans and compare its performance to that of less-experienced readers. METHODS: We used bi-parametric prostate MRI scans from the PI-CAI dataset in this study. A 3-point Likert scale, consisting of poor, moderate, and excellent, was utilized for assessing image quality. Three expert readers established the ground-truth labels for the development (500) and testing sets (100). We trained a 3D DL model on the development set using probabilistic prostate masks and an ordinal loss function. Four less-experienced readers scored the testing set for performance comparison. RESULTS: The kappa scores between the DL model and the expert consensus for T2W images and ADC maps were 0.42 and 0.61, representing moderate and good levels of agreement. The kappa scores between the less-experienced readers and the expert consensus for T2W images and ADC maps ranged from 0.39 to 0.56 (fair to moderate) and from 0.39 to 0.62 (fair to good). CONCLUSIONS: Deep learning (DL) can offer performance comparable to that of less-experienced readers when assessing image quality in bi-parametric prostate MRI, making it a viable option for an automated quality assessment tool. We suggest that DL models trained on more representative datasets, annotated by a larger group of experts, could yield reliable image quality assessment and potentially substitute or assist visual evaluations by human readers.

Normative reference values of major thoracic arterial vasculature in Turkiye.

OBJECTIVE: The aim of this study was to determine normative reference values for major thoracic arterial vasculature in Turkiye and to evaluate differences according to age and gender. METHODS: Low-dose unenhanced chest computerized tomography images acquired with pre-diagnosis of COVID-19 between March and June 2020 were evaluated retrospectively. Patients with known chronic lung parenchymal disease, pleural effusion, pneumothorax, chronic diseases such as diabetes, hypertension, obesity, and chronic heart diseases (coronary artery disease, atherosclerosis, congestive heart failure, valve replacement, and arrhythmia) were excluded from the study. The ascending aorta diameter (AAD), descending aorta diameter (DAD), aortic arch diameter (ARCAD), main pulmonary artery diameter (MPAD), right pulmonary artery diameter (RPAD), and the left pulmonary artery diameter (LPAD) were measured in the same sections by standardized methods. The variability of parameters according to age (<40 years; ≥40 years) and gender (male to female) was evaluated by statistical methods. The Student's t test was used to compare the normal distribution according to the given quantitative age and gender, while the data that did not fit the normal distribution were compared with the Mann-Whitney U test. The conformity of the data to the normal distribution was tested with the Kolmogorov-Smirnov, Shapiro-Wilk test, and graphical examinations. RESULTS: Totally 777 cases between the ages of 18-96 (43.80±15.98) were included in the study. Among these, 52.8% (n=410) were male and 47.2% (n=367) were female. Mean diameters were 28.52±5.13 mm (12-48 mm in range) for AAD, 30.83±5.25 mm (12-52 mm in range) for ARCAD, DAD 21.27±3.57 mm (11-38 mm in range) for DAD; 23.27±4.03 mm (14-40 mm in range) for MPAD, 17.27±3.19 mm (10-30 mm in range) for RPAD, and 17.62±3.06 mm (10-37 mm in range) for LPAD. Statistically significantly higher values were obtained in all diameters for cases over 40 years of age. Similarly, higher values were obtained in all diameters for males compared to females. CONCLUSION: The diameters of all thoracic main vascular structures are larger in men than in women and increase with age.

CT Findings of the Massive Air Embolism in a Case with Thoracic Gunshot Wound: A Special Case Report as if a Whole Body Pneumo- Angiography was Performed.

BACKGROUND: Massive Systemic Arterial Air Embolism (SAAE) associated with penetrating trauma is a rare condition. A few cases were reported for massive arterial air embolism in the literature. Computed tomography is a fast and easily accessible modality for detecting air in the vasculature. We report CT findings of a rare case with a thoracic gunshot wound, which demonstrate air almost in all systemic vessels like ''full body pneumoangiography''. CASE PRESENTATION: A 42-year-old male patient with a thoracic gunshot wound was admitted to the Accident and Emergency (A&E) unit in a state of cardiac arrest. Postmortem Computed Tomography (CT) was performed and extensive air was revealed in several great vessels. CONCLUSION: We conclude that the underline causes of massive air embolism in our case are two main mechanisms: firstly, massive air enters the vasculature via bronchovascular fistula as there was bilateral lung contusion and directly through cardiac truncus, secondly while CPR was being conducted, massive air was pumped to the systemic circulation.

Verbal and Nonverbal Memory in Neurodegenerative and Stroke Aphasia: Evidence From the Turkish Version of the Three Words Three Shapes Test.

BACKGROUND: Although language impairment is the most salient feature of cognitive impairment in both primary progressive aphasia (PPA) and stroke aphasia (SA), memory can also be impaired in both patient populations. OBJECTIVE: To identify distinctive features of verbal and nonverbal memory processing in individuals with PPA and those with SA. METHOD: We gave individuals with PPA (n = 14), those with SA (n = 8), and healthy controls (HC; n = 13) a comprehensive neuropsychological test battery and the Turkish version of the Three Words Three Shapes Test (3W3S-Turkish). The 3W3S-Turkish Test includes five subtests: Copy, Incidental Recall, Acquisition, Delayed Recall, and Recognition. High-resolution brain scans were performed in a subset of individuals with PPA and those with SA. Lesion distribution was limited to the dorsal language areas in the SA group, whereas peak atrophy areas in the PPA group extended beyond the language network, including the medial temporal lobe, precuneus, and posterior/medial portions of the cingulate cortex. RESULTS: Both the PPA and SA groups showed impairment in incidental recall, and the PPA group showed additional impairment in delayed recall. Greater impairment for verbal stimuli suggestive of material-specific memory impairment was evident in the PPA group's scores on the Incidental Recall and Delayed Recall subtests. Both aphasia groups retained the acquired information regardless of material type. CONCLUSION: Although both aphasia groups shared similarities in the involvement of the dorsal prefrontal working memory/attention network, the PPA group showed greater impairment in delayed recall compared with the SA group.

Comparison of Olfactory Cleft Width and Volumes in Patients with COVID-19 Anosmia and COVID-19 Cases Without Anosmia.

INTRODUCTION: The aim of this study was to assess the relationship between olfactory cleft width/volume and COVID-19-related anosmia. METHODS: This study consisted of PCR-proven COVID-19 patients. Cases with COVID-19-related anosmia constituted Group 1 and cases without any olfactory dysfunction (OD) throughout COVID-19 infection or after recovery constituted Group 2. A total of 50 patients were included in the study, comprising 24 cases in Group 1 and 26 cases in Group 2. Group 1 patients underwent a 4-item-odor identification test during active symptoms and a Sniffin' Sticks test after reconversion of PCR results to negative. All patients in Group 2 also underwent the Sniffin' Stick test to document normosmia. All cases had paranasal sinus CT performed. Olfactory cleft widths and olfactory volumes were measured. The differences in width and volume between groups and the correlation with odor test scores (threshold-discrimination-identification [TDI]) were calculated. In addition, regression analyzes analysis was performed for cleft widths, volumes, and TDI scores according to age. RESULTS: Olfactory cleft widths and olfactory volumes were significantly higher in Group 1 than those in Group 2 (p = 0.001; p < 0.01). There was a significant negative correlation between total TDI scores and olfactory cleft widths and total olfactory volumes (r = -0.665; r = -0.731, respectively). Patients younger than 40 years of age had significantly higher right olfactory cleft width, left olfactory cleft width, and olfactory cleft volume than those in patients older than 40 years of age (p = 0.004, p = 0.005, p = 0.003; p < 0,01, respectively). However, patients younger than 40 years of age had a significantly lower total TDI score and in all other values individually (t-d-i) than those in patients older than 40 years of age (p = 0.004; p < 0.01). CONCLUSION: Patients with COVID-19-related OD had larger olfactory cleft width and volumes than those without OD in this study. Total TDI score was found to be inversely correlated with cleft width and volume.

Evaluation of the Effect of Age, Menopausal Status, and Parity on Breast Parenchyma Stiffness by Multiparametric Shear Wave Elastography.

RATIONALE AND OBJECTIVES: To evaluate the relationship between quantitative breast parenchyma stiffness by using multiparametric shear wave elastography (mpSWE) and the potential risk factors of breast cancer. MATERIAL AND METHODS: The Vmean, Vmax, Vmin, Vsd values were measured with mpSWE from each breast and each quadrant in all cases under and over the age of 40. Statistical analysis was performed to evaluate the relationship between breast stiffness and age, side, quadrant, menopausal status, mammographic breast density, and obstetric history. RESULTS: The study cohort included 964 breasts of 482 patients, where 342 patients were ≥40 years of age; and 140 cases were <40 years of age with a mean age of 45.07 ± 10.96. No significant difference in breast stiffness was detected between right and left breasts (p > 0.05); however, upper quadrants were found to be stiffer than the lower quadrants (p < 0.05). The effect of age on all values was found to be significant (p < 0.05), and stiffness increased with age. All mpSWE values of post-menopausal cases were significantly higher (p < 0.05) than premenopausal cases. Nulliparous cases had higher values than cases with prior parity (p < 0.05). Cases with Type C and D breast density had higher stiffness values than those with Type A and Type B breast density. CONCLUSION: Breast parenchyma shows increased stiffness in in post-menopausal, nulliparous and older patients and patients with dense breast density. Similar to the mammographic increased breast density, elastographically increased breast parenchymal stiffness may be used as a possible risk factor for breast cancer or as a predictor of breast cancer.

A Comparative Olfactory MRI, DTI and fMRI Study of COVID-19 Related Anosmia and Post Viral Olfactory Dysfunction.

RATIONALE AND OBJECTIVE: To evaluate how COVID-19 anosmia imaging findings resembled and differed from postinfectious 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% - 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.

Evaluation of Multiparametric Shear Wave Elastography Indices in Malignant and Benign Breast Lesions.

RATIONALE AND OBJECTIVES: To evaluate the shear wave elastography indices (multiparametric SWE) of breast lesions based on patient and lesion dependent features and assess the contribution of different elastographic parameters to radiological diagnosis. MATERIALS AND METHODS: Effect of patient-dependent (age and menopausal status) and lesion-dependent (distance from the areola, quadrant location, size, depth, margin and shape) factors on SWE parameters (Vmean, Vsd, Vmax, Vmin) in benign breast lesions were assessed. Only mass lesions were included in the study. Sensitivity, specificity, PPV, NPV and cut-off values for each elastography parameter was calculated. RESULTS: A total of 496 mass lesions of breast were evaluated. 467 of the lesions were benign and 29 were malignant. There was no significant relationship among SWE indices and age, menopausal status, lesion shape and distance to the areola in benign lesions (p>0.05). SWE indices were found to be associated with lesion margin, depth from the skin, and lesion size in benign lesions (p<0.05). All BI-RADS 3 lesions that underwent biopsy were benign (n:35); 23.5% of 4a lesions were malignant (n:4/17) and all 4b-4c-5 lesions were malignant (n:25/25). The cut-off values for malignant lesions were: Vmean 3.38 m/s, Vsd 0.81, Vmax 6.87 m/s, Vmin 1.53 m/s. All SWE parameters were statistically significant in predicting malignancy on ROC analysis, Vmax was the most sensitive (96.3%) and specific (94.7%) parameter. Cut-off values for Vmax was 6.87 m/s with an accuracy rate of 94.7%, and 3.37 m/s for Vmean and 0.8 for Vsd with 92.5% accuracy. CONCLUSION: The SWE parameters to predict malignancy in breast lesions can be affected by lesion dependent features, whereas no significant effect of patient's age or menopausal status on stiffness of the lesions was observed. Vmax had the highest sensitivity for predicting malignancy.

A practical approach to imaging characteristics and standardized reporting of COVID-19: a radiologic review.

Novel coronavirus (2019-nCoV), also known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a pathogen that has caused a rapidly spreading pandemic all over the world. The primary mean of transmission is inhalation with a predilection for respiratory system involvement, especially in the distal airways. The disease that arises from this novel coronavirus is named coronavirus disease 2019 (COVID-19). COVID-19 may have a rapid and devastating course in some cases leading to severe complications and death. Radiological imaging methods have an invaluable role in diagnosis, follow-up, and treatment. In this review, radiological imaging findings of COVID-19 have been systematically reviewed based on the published literature so far. Radiologic reporting templates are also emphasized from a different point of view, considering specific distinctive patterns of involvement.

Imaging Features to Predict Response to Olfactory Training in Post-Traumatic Olfactory Dysfunction.

OBJECTIVES/HYPOTHESIS: Prognosis of post-traumatic olfactory dysfunction is poor, with medical treatment options showing limited success rates. Olfactory training (OT) has been introduced as a potential therapeutic option in olfactory dysfunction. We aimed to identify the imaging features that would predict a better response to OT and create an imaging-based prognostic scale. METHODS: We retrospectively reviewed 52 patients that underwent OT at our center for post-traumatic olfactory dysfunction. Olfactory functions at the time of initial presentation and at completion of OT were evaluated using Sniffin' Sticks test and threshold discrimination identification (TDI) scores were calculated. Patients were divided into responders (ROT group: 16 cases) and non-responders (n-ROT group: 36 cases) to OT based on TDI score change (cut-off 5.5 point). Morphological measurements of olfactory fossa, olfactory bulb volume and signal abnormalities, olfactory nerve filia integrity, siderosis, encephalomalacic changes in olfactory cortex, and other cortical regions were reviewed. RESULTS: There was no significant difference between the two groups in terms of age, gender distribution, olfactory dysfunction duration, head-trauma severity, and initial TDI scores. A model incorporating five variables: cribriform plate fracture, olfactory fossa depth (cut-off: 4.9 mm), olfactory bulb encephalomalacia, olfactory bulb volume (cut-off: 27.1 mm3 ), and siderosis was developed. This model had an area under the curve (AUC) of 0.950, and a cut-off value of 1 had 76.5% sensitivity and 97.1% specificity in prediction of response to OT. CONCLUSIONS: We developed an imaging-based scoring system with good specificity that can be used as an adjunctive tool for patient counseling, and optimal selection of management options. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E2243-E2250, 2021.

Olfactory Cleft Width and Volume: Possible Risk Factors for Postinfectious Olfactory Dysfunction.

OBJECTIVES/HYPOTHESIS: Upper respiratory tract infections are a common cause of temporary and permanent olfactory dysfunction in the general population. Postviral or postinfectious olfactory loss (PIOL) develops only in rare cases. The aim of this study was to investigate the anatomical features of olfactory cleft (OC) in patients with PIOL to shed light on possible predisposing factors for PIOL. STUDY DESIGN: Retrospective study. METHODS: We retrospectively evaluated paranasal sinus computed tomography (CT) scan results of patients diagnosed with PIOL. A control group consisted of normosmic individuals who underwent paranasal sinus CT scans before septoplasty surgery. We compared the olfactory fossa depth, OC width, and volume on the CT scans of the PIOL and control groups. RESULTS: In total, 71 individuals fulfilled the study criteria (PIOL group, n = 32; control group, n = 39). There was no statistically significant difference in the olfactory fossa depth in the two groups. The OC width and volume in the PIOL group was found to be significantly increased than that in the control group (P < .001 for both). CONCLUSIONS: Patients with PIOL had increased OC width and volume than the healthy controls. An extra-wide olfactory cleft may be a predisposing factor in the pathogenesis of PIOL. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:5-9, 2021.

Predictive value of CT imaging findings in COVID-19 pneumonia at the time of first-screen regarding the need for hospitalization or intensive care unit.

PURPOSE: In this study, we aimed to reveal the relationship between initial lung parenchymal involvement patterns and the subsequent need for hospitalization and/or intensive care unit admission in coronavirus disease 2019 (COVID-19) positive cases. METHODS: Overall, 231 patients diagnosed with COVID-19 as proven by PCR were included in this study. Based on the duration of hospitalization, patients were divided into three groups as follows: Group 1, patients receiving outpatient treatment or requiring hospitalization <7 days; Group 2, requiring hospitalization ≥7 days; Group 3, patients requiring at least 1 day of intensive care at any time. Chest CT findings at first admission were evaluated for the following features: typical/atypical involvement of the disease, infiltration patterns (ground-glass opacities, crazy-paving pattern, consolidation), distribution and the largest diameters of the lesions, total lesion numbers, number of affected lung lobes, and affected total lung parenchyma percentages. The variability of all these findings according to the groups was analyzed statistically. RESULTS: In this study, 172 patients were in Group 1, 39 patients in Group 2, and 20 patients in Group 3. The findings obtained in this study indicated that there was no statistically significant difference in ground-glass opacity rates among the groups (p = 0.344). The rates of crazy-paving and consolidation patterns were significantly higher in Groups 2 and 3 than in Group 1 (p = 0.001, p = 0.002, respectively). The rate of right upper, left upper lobe, and right middle lobe involvements as consolidation pattern was significantly higher in Group 3 than in Group 1 (p = 0.148, p = 0.935, p = 0.143, respectively). A statistically significant difference was also found between the affected lobe numbers, total lesion numbers, the diameter of the largest lesion, and the affected lung parenchyma percentages between the groups (p = 0.001). The average number of impacted lobes in Group 1 was 2; 4 in Group 2 and Group 3. The mean percentage of affected lung parenchyma percentage was 25% in Group 1 and Group 2, and 50% in Group 3. CONCLUSION: In case of infiltration dominated by right middle or upper lobe involvement with a consolidation pattern, there is a higher risk of future intensive care need. Also, the need for intensive care increases as the number of affected lobes and percentage of affected parenchymal involvement increase.

Relationship between disease severity and serum IL-6 levels in COVID-19 anosmia.

BACKGROUND: An association between IL-6 levels and cytokine storm syndrome in COVID-19 patients has been suggested. Cases with higher IL-6 levels have more rapid progression and a higher complication rate. On the other hand, COVID-19 cases with anosmia have a milder course of the disease. OBJECTIVE: We aimed to investigate whether there is a relationship between serum IL-6 levels and presence of anosmia in COVID-19 patients. METHODS: Patients with a confirmed diagnosis of COVID-19 based on laboratory (PCR) were stratified into two groups based on presence of olfactory dysfunction (OD). In all cases with and without anosmia; psychophysical test (Sniffin' Sticks test) and a survey on olfactory symptoms were obtained. Threshold (t) - discrimination (d) - identification (i), and total (TDI) scores reflecting olfactory function were calculated. Clinical symptoms, serum IL-6 levels, other laboratory parameters, and chest computed tomography (CT) findings were recorded. RESULTS: A total of 59 patients were included, comprising 23 patients with anosmia and 36 patients without OD based on TDI scores. Patients with anosmia (41.39 ± 15.04) were significantly younger compared to cases without anosmia (52.19 ± 18.50). There was no significant difference between the groups in terms of comorbidities, smoking history, and symptoms including nasal congestion and rhinorrhea. Although serum IL-6 levels of all patients were above normal values (7 pg/mL), patients with anosmia had significantly lower serum IL-6 levels (16.72 ± 14.28 pg/mL) compared to patients without OD (60.95 ± 89.33 pg/mL) (p = 0.026). CONCLUSION: Patients with COVID-19 related anosmia tend to have significantly lower serum levels of IL-6 compared to patients without OD, and the lower IL-6 levels is related to milder course of the disease. With the effect of low cytokine storm and IL-6 level, it may be said that anosmic cases have a milder disease in COVID-19.

A new imaging sign in COVID-19 pneumonia: vascular changes and their correlation with clinical severity of the disease.

PURPOSE: It has come to our attention that specific vascular changes (VCs) appear more frequently in chest computed tomography (CT) of patients with coronavirus disease 2019 (COVID-19). In this study, we aimed to investigate if these specific VCs in chest CT correlate with clinical severity of the disease. METHODS: CT images of 102 patients who underwent low-dose noncontrast chest CT due to COVID-19 between 11 March 2020 and 11 April 2020 were evaluated retrospectively. The patients were divided into two groups based on the presence of VCs in CT images. VCs in chest CT of patients with COVID-19 were defined using the following descriptors: decreased lumen caliber, vascular wall irregularity, angulation in the course of the vessel, vascular disruption, and/or interruption. The relationship of these VCs with disease symptoms (fever, cough, shortness of breath), comorbid conditions (diabetes, hypertension, asthma), smoking habit, disease-specific laboratory changes (white blood cell-lymphocyte count, neutrophil/lymphocyte ratio, C-reactive protein [CRP], D-dimer, lactate dehydrogenase [LDH], ferritin, procalcitonin), lung parenchymal infiltration pattern (ground-glass opacity, crazy-paving pattern, consolidation) and its distribution (peripheral, central, mixed, upper lobes, lower lobes, right middle lobe) on CT were investigated by comparison of these variables between patients with and without VCs in chest CT. RESULTS: VCs were observed in 18 out of 102 patients (18%) with typical parenchymal involvement for COVID-19. There was no significant difference in terms of age and sex. We found an irregularity in the wall of the vascular structures in the distal branches and decreased lumen caliber of the vessels related to ground-glass opacities in 15 patients, concentric luminal narrowing in annular form in 4 patients, angulation/traction or springiness in the vascular structures towards the active lesions in 3 patients, and interruptions along the vascular course in 1 patient. VCs were significantly correlated with fever (12/18, 66.7%) and shortness of breath (7/18, 39%). These changes were significantly more remarkable in common disease involving both upper and lower lobes (10/18, 56%). In these cases, there was a substantial increase in CRP (15/18, 83%; mean, 5.7±6.3 mg/dL) and LDH (8/18, 44%) values compared to those who did not have any VCs. CONCLUSION: The results of this study suggest that specific VCs observed in chest CT may predict the disease severity in cases of COVID-19 pneumonia. These changes may be related to respiratory distress in the disease.

Olfactory Cleft Measurements and COVID-19-Related Anosmia.

OBJECTIVE: This study aimed to investigate the differences in olfactory cleft (OC) morphology in coronavirus disease 2019 (COVID-19) anosmia compared to control subjects and postviral anosmia related to infection other than severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). STUDY DESIGN: Prospective. SETTING: This study comprises 91 cases, including 24 cases with anosmia due to SARS-CoV-2, 38 patients with olfactory dysfunction (OD) due to viral infection other than SARS-CoV-2, and a control group of 29 normosmic cases. METHODS: All cases had paranasal sinus computed tomography (CT), and cases with OD had magnetic resonance imaging (MRI) dedicated to the olfactory nerve. The OC width and volumes were measured on CT, and T2-weighted signal intensity (SI), olfactory bulb volumes, and olfactory sulcus depths were assessed on MRI. RESULTS: This study showed 3 major findings: the right and left OC widths were significantly wider in anosmic patients due to SARS-CoV-2 (group 1) or OD due to non-SARS-CoV-2 viral infection (group 2) when compared to healthy controls. OC volumes were significantly higher in group 1 or 2 than in healthy controls, and T2 SI of OC area was higher in groups 1 and 2 than in healthy controls. There was no significant difference in olfactory bulb volumes and olfactory sulcus depths on MRI among groups 1 and 2. CONCLUSION: In this study, patients with COVID-19 anosmia had higher OC widths and volumes compared to control subjects. In addition, there was higher T2 SI of the olfactory bulb in COVID-19 anosmia compared to control subjects, suggesting underlying inflammatory changes. There was a significant negative correlation between these morphological findings and threshold discrimination identification scores. LEVEL OF EVIDENCE: Level 4.

Olfactory Bulb MRI and Paranasal Sinus CT Findings in Persistent COVID-19 Anosmia.

BACKGROUND AND PURPOSE: There is limited literature consisting of case reports or series on olfactory bulb imaging in COVID-19 olfactory dysfunction. An imaging study with objective clinical correlation is needed in COVID-19 anosmia in order to better understand underlying pathogenesis. MATERIAL AND METHODS: We evaluated 23 patients with persistent COVID-19 olfactory dysfunction. Patients included in this study had a minimum 1-month duration between onset of olfactory dysfunction and evaluation. Olfactory functions were evaluated with Sniffin' Sticks Test. Paranasal sinus CTs and MRI dedicated to olfactory nerves were acquired. On MRI, quantitative measurements of olfactory bulb volumes and olfactory sulcus depth and qualitative assessment of olfactory bulb morphology, signal intensity, and olfactory nerve filia architecture were performed. RESULTS: All patients were anosmic at the time of imaging based on olfactory test results. On CT, Olfactory cleft opacification was seen in 73.9% of cases with a mid and posterior segment dominance. 43.5% of cases had below normal olfactory bulb volumes and 60.9% of cases had shallow olfactory sulci. Of all, 54.2% of cases had changes in normal inverted J shape of the bulb. 91.3% of cases had abnormality in olfactory bulb signal intensity in the forms of diffusely increased signal intensity, scattered hyperintense foci or microhemorrhages. Evident clumping of olfactory filia was seen in 34.8% of cases and thinning with scarcity of filia in 17.4%. Primary olfactory cortical signal abnormality was seen in 21.7% of cases. CONCLUSION: Our findings indicate olfactory cleft and olfactory bulb abnormalities are seen in COVID-19 anosmia. There was a relatively high percentage of olfactory bulb degeneration. Further longitudinal imaging studies could shed light on the mechanism of olfactory neuronal pathway injury in COVID-19 anosmia.

A new perspective on imaging of olfactory dysfunction: Does size matter?

PURPOSE: This study assesses the diagnostic utility of olfactory nerve and bulb morphologies in addition to volumetric analysis in classification of different olfactory dysfunction etiologies. METHODS: 106 patients presenting with olfactory loss and 17 control subjects were included. Based on detailed anamnesis, smell test and ear-nose-throat examination; patients were categorized into four groups as post-viral, post-traumatic, idiopathic, and obstructive olfactory dysfunction. Olfactory region was imaged with paranasal sinus CT and MRI dedicated to olfactory nerve. Olfactory bulb volume and olfactory sulcus depths were calculated on MRI. The olfactory bulb was assessed for morphology, contour lobulations and T2-signal intensity; and olfactory nerve for uniformity and clumping. RESULTS: Volumetric analysis showed decreased olfactory bulb volume in idiopathic and obstructive group compared to control subjects. Olfactory sulci were shallower in post-viral, post-traumatic, idiopathic, and obstructive group compared to the control group. In post-viral group; olfactory bulbs had lobulated contour and focal T2-hyperintense regions in 67 % of cases, and olfactory nerves had a clumped and thickened appearance in 66 % of cases. In idiopathic group, olfactory bulbs were rectangular shaped with minimally deformed contours, and olfactory nerves were thin and hard to delineate. No specific olfactory bulb or nerve pattern was identified in obstructive and post-traumatic groups, however closed olfactory cleft and siderotic frontobasal changes were helpful clues in obstructive and post-traumatic groups, respectively. CONCLUSION: In addition to olfactory cleft patency, olfactory sulcus depth and olfactory bulb volume; bulb and nerve morphologies may provide diagnostic information on different etiologies of olfactory dysfunction.