Linear Opacities Research Articles

Idiopathic Inflammatory Myopathies-associated Interstitial Lung Disease in Adults.

Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of autoimmune diseases characterized by muscle involvement and various extramuscular manifestations. Interstitial lung disease (ILD) is one of the most common extramuscular manifestations of IIM and is associated with significant mortality and morbidity. The clinical phenotypes, treatment responses, and prognosis of IIM-ILD are significantly related to myositis-specific antibody (MSA) profiles, with some racial differences. The features associated with MSA in IIM-ILD could also be relevant to cases of ILD where MSA is present but does not meet the criteria for IIM. The anti-melanoma differentiation-associated gene 5 antibody is highly associated with rapidly progressive ILD (RP-ILD), especially in Asian populations, and with characteristic cutaneous manifestations, such as skin ulcers. Radiologically, ground-glass opacities, consolidations, and nonsegmental linear opacities were more predominant than reticular opacities and honeycombing. While the mortality rate is still around 30%, the prognosis can be improved with early intensive therapy with corticosteroids and multiple immunosuppressants. In contrast, anti-aminoacyl-tRNA synthetase (ARS) antibodies are associated with chronic ILD, although RP-ILD is also common. Patients with anti-ARS antibodies often show lung-predominant presentations, with subtle muscle and skin involvement. Radiologically, reticular opacities, with or without consolidation, are predominant and may progress to honeycombing over time. Combination therapy with corticosteroids and a single immunosuppressant is recommended to prevent relapses, which often lead to a decline in lung function and fatal long-term outcomes. Significant advances in immunology and genetics holds promise for fostering more personalized approaches to managing IIM-ILD.

Diffuse pulmonary arteriovenous malformation presenting with secondary polycythemia and headaches: a case report

BackgroundPulmonary arteriovenous malformations are a relatively uncommon medical condition, affecting roughly 1 in every 2500 individuals. Of those suffering from pulmonary arteriovenous malformations, 80% have an underlying genetic condition: hereditary hemorrhagic telangiectasia.Case presentationWe present the case of a 20-year-old Pakistani male with a history of persistent slower-onset frontal headaches that increased in severity within the course of the day. His hemoglobin was 18 g/dl, indicating polycythemia, for which he had undergone seven venesections in a month previously. His physical examination was unremarkable. His computed tomography scan depicted multiple dilated tortuous vessels with branching linear opacities in the right lower lobe of the lungs. The multiple feeding arteries were supplied by the right main pulmonary artery, and the large draining veins led to the right inferior pulmonary vein. This was identified as a diffuse pulmonary arteriovenous malformation. He was recommended for a right pulmonary artery angiogram. It showed multiple tortuous vessels with a nidus and large draining veins—features of a diffuse arteriovenous malformation in the right lower lobe of the lung consistent with the computed tomography scan. Embolization of two of these vessels feeding the arteriovenous malformation was conducted, using Amplatzer Vascular plug 2, whereas multiple pushable coils (five coils) were used for embolizing the third feeding vessel. This achieved 70–80% successful embolization of right pulmonary AVM; however, some residual flow was still seen in the arteriovenous malformation given the complexity of the lesion. Immediately after, his oxygen saturation improved from 78% to 96%.ConclusionDiffuse pulmonary arteriovenous malformations, as seen in this patient, are rare, accounting for less than 5% of total pulmonary arteriovenous malformations diagnosed. The patient presented with a complaint of progressive frontal headaches, which can be attributed to low oxygen saturation or the presence of a cerebral arteriovenous malformation. There was no history of hereditary hemorrhagic telangiectasia in the patient’s family. Furthermore, although most patients with hereditary hemorrhagic telangiectasia and hence pulmonary arteriovenous malformation have complaints of iron-deficiency anemia, our patient in contrast was suffering from polycythemia. This can be explained as a compensatory mechanism in hypoxemic conditions. Moreover, the patient had no complaint of hemoptysis or epistaxis, giving a varied presentation in comparison with a typical pulmonary arteriovenous malformation.

Persistent Residual Lung Abnormalities (PRLAs) as Post COVID Lung Sequel in Recovered Severe Pneumonia Case with Lung Function Abnormality at Two Year Follow Up

Coronavirus related (SARS-CoV-2) global pandemic has caused significant mortality and morbidity globally in the last three years. Although, pandemic has waned since last year, we are not in great peace of relief due to lingering effects of COVID-19 persisted even after two years of illness. Radiological phenotypes are radiological patterns or observable characteristics of COVID-19 pneumonia. Radiological outcomes are initially interpreted as post covid lung fibrosis in short term follow-up of recovered COVID-19 cases in post covid care settings and during long term evaluation these abnormalities are defined as post covid sequalae’s. In present case report, 38-year male, presented in outdoor unit for shortness of breath on exertion with history of severe COVID-19 Pneumonia resulted into acute respiratory distress syndrome with hospitalization in intensive care unit one year back and required high flow nasal cannula (HFNC) with Non-invasive ventilatory support (NIV) for two weeks. He was offered oxygen supplementation at home with antibiotics for three months and no requirement of oxygen and some respiratory symptoms even after one year. His HRCT thorax documented at one year of discharge from hospital revealed typical interstitial opacities labelled as Persistent Residual lung abnormalities (RLAs) which are predominantly reticular and linear opacities in peripheral parts of lungs without honeycombing within typical pleural based areas with parenchymal bands and minimally altered lung architecture and preserved lung volume.

Diagnostic performance of chest CT average intensity projection (AIP) reconstruction for the assessment of pleuro-parenchymal abnormalities

The comparison between chest x-ray (CXR) and computed tomography (CT) images is commonly required in clinical practice to assess the evolution of chest pathological manifestations. Intrinsic differences between the two techniques, however, limit reader confidence in such a comparison. CT average intensity projection (AIP) reconstruction allows obtaining "synthetic" CXR (s-CXR) images, which are thought to have the potential to increase the accuracy of comparison between CXR and CT imaging. We aim at assessing the diagnostic performance of s-CXR imaging in detecting common pleuro-parenchymal abnormalities. 142 patients who underwent chest CT examination and CXR within 24 hours were enrolled. CT was the standard of reference. Both conventional CXR (c-CXR) and s-CXR images were retrospectively reviewed for the presence of consolidation, nodule/mass, linear opacities, reticular opacities, and pleural effusion by 3 readers in two separate sessions. Sensitivity, specificity, accuracy and their 95% confidence interval were calculated for each reader and setting and tested by McNemar test. Inter-observer agreement was tested by Cohen's K test and its 95%CI. Overall, s-CXR sensitivity ranged 45-67% for consolidation, 12-28% for nodule/mass, 17-33% for linear opacities, 2-61% for reticular opacities, and 33-58% for pleural effusion; specificity 65-83%, 83-94%, 94-98%, 93-100% and 79-86%; accuracy 66-68%, 74-79%, 89-91%, 61-65% and 68-72%, respectively. K values ranged 0.38-0.50, 0.05-0.25, -0.05-0.11, -0.01-0.15, and 0.40-0.66 for consolidation, nodule/mass, linear opacities, reticular opacities, and pleural effusion, respectively. S-CXR images, reconstructed with AIP technique, can be compared with conventional images in clinical practice and for educational purposes.

Postcataract surgery gray-white lines of the corneal endothelium viewed with confocal microscopy and review of literature

Introduction: Cataract surgery rarely causes 1-day postoperative corneal endothelial changes visibly seen as patches or linear streaks. Previously described as “snailtracks,” these changes have been studied using slitlamp examination (SLE), scanning electron microscopy, and specular microscopy, but to the best of the authors' knowledge, it has yet to be analyzed using confocal microscopy. Patient and Clinical Findings: 3 patients who underwent cataract surgery through phacoemulsification with intraocular lens implant were found to have snailtracks on the corneal endothelium during postoperative day 1 examination. Diagnosis, Intervention, and Outcomes: The corneal endothelium of the 3 identified patients underwent SLE and in vivo confocal microscopy on postoperative day 1 and postoperative week 1. On day 1, linear opacities were visible on the corneal endothelia and confocal microscopy revealed disruptions of the regular polygonal endothelial pattern with cell aggregation. At 1 week, opacities had resolved and confocal microscopy demonstrated reorganization of the endothelia and appearance of hyperreflective nuclei. Conclusions: Confocal microscopy of postcataract surgery snailtracks supports the hypothesis that such endothelial opacification is secondary to trauma to the endothelium.

Comparison of Initial Thoracic CT Images of COVID-19 Patients with Non-Variant, Alpha, Delta, and Omicron Variants: A Retrospective Study

Background:: CT findings and Ground glass opacity (GGO) volumes may differ between SARS CoV-2 non-variant, alpha, delta, and omicron variants. Objective:: To compare the thoracic CT findings, GGO volumes, and GGOs’ lung uptake rates among patients with COVID-19 variants. Methods:: Thoracic CT images of 83 patients with non-variant, 78 patients with alpha variant, 93 patients with delta variant, and 73 patients with omicron variant having positive Real-Time Polymerase Chain Reaction test results were analyzed retrospectively. GGO volumes and lung volumes were calculated by using the Cavalieri Principle. Differences in CT findings, ground-glass opacity volumes, and lung involvement rates between non-variant and variant groups were evaluated. Results:: There were significant differences found in the incidence of GGOs (p < 0.001), air bronchogram (p = 0.007), reticulation (p = 0.002) and subpleural lines, and linear opacities (p = 0.034) between non-variant and variant groups. GGO uptake rates (ground glass opacity volumes × 100 ÷ lung volume) were 8.88% in the non-variant, 4.83% in the alpha variant, 3.50% in the delta variant, and 2.02% in the omicron variant. In estimating variant groups, it was determined that the increase in the rate of GGOs in the right lung increased the probability of having an omicron variant, whereas the presence of nodules decreased it. The possibility of the delta variant increased with an increase in the rate of ground glass opacities in the left lung. Conclusion:: Thoracic CT findings solely can be helpful in distinguishing COVID-19 variants. Decreased frequency of uptake rates of GGOs suggested that the severity of COVID-19 disease was gradually decreasing.

Comparison of Computed Tomography and Clinical Features Between Patients Infected with the SARS-CoV-2 Omicron Variant and the Original Strain.

To investigate potential differences in clinical and computed tomography (CT) features between patients with the SARS-CoV-2 Omicron variant and the original strain. This retrospective study included 69 hospitalized patients infected with Omicron variant from November to December 2022, and 96 hospitalized patients infected with the original strain from February to March 2020 in Chongqing, China. The clinical features, CT manifestations, degrees of lung involvement in different stages on CT, and imaging changes after the reverse-transcription polymerase chain reaction (RT-PCR) results turned negative were compared between the two groups. For clinical features, patients with Omicron were predominantly old people and females, without manifestation of any clinical symptoms, who had low serum levels of C-reactive protein and procalcitonin. Shorter interval from symptoms onset to initial CT scan was observed in Omicron patients compared to patients with the original strain (all P < 0.05). For CT features, patients with Omicron were more likely to present with round-like opacities and tree-in-bud pattern (all P < 0.05), but less likely to exhibit a diffuse distribution, patchy and linear opacities, as well as vascular enlargement pattern (all P < 0.05). The Omicron group was more susceptible to exhibiting lower CT involvement scores in each stage (all P < 0.05) and imaging progression after the RT-PCR results turned negative (P < 0.001). Patients infected with the Omicron variant exhibited less severe changes on chest CT compared to those infected with the original strain. Furthermore, imaging progression under low viral load conditions was more common in patients with Omicron than in those with the original strain.

Omicron variant and pulmonary involvements: a chest imaging analysis in asymptomatic and mild COVID-19.

To identify clinical characteristics and risk factors for pulmonary involvements in asymptomatic and mildly symptomatic patients infected with SARS-CoV-2 Omicron variant by chest imaging analysis. Detailed data and chest computed tomography (CT) imaging features were retrospectively analyzed from asymptomatic and mildly symptomatic patients infected with Omicron between 24 April and 10 May 2022. We scored chest CT imaging features and categorized the patients into obvious pulmonary involvements (OPI) (score > 2) and not obvious pulmonary involvements (NOPI) (score ≤ 2) groups based on the median score. The risk factors for OPI were identified with analysis results visualized by nomogram. In total, 339 patients were included (145 were male and 194 were female), and the most frequent clinical symptoms were cough (75.5%); chest CT imaging features were mostly linear opacities (42.8%). Pulmonary involvements were more likely to be found in the left lower lung lobe, with a significant difference in the lung total severity score of the individual lung lobes (p < 0.001). Logistic regression analysis revealed age stratification [odds ratio (OR) = 1.92, 95% confidence interval (CI) (1.548-2.383); p < 0.001], prolonged nucleic acid negative conversion time (NCT) (NCT > 8d) [OR = 1.842, 95% CI (1.104-3.073); p = 0.019], and pulmonary diseases [OR = 4.698, 95% CI (1.159-19.048); p = 0.03] as independent OPI risk factors. Asymptomatic and mildly symptomatic patients infected with Omicron had pulmonary involvements which were not uncommon. Potential risk factors for age stratification, prolonged NCT, and pulmonary diseases can help clinicians to identify OPI in asymptomatic and mildly symptomatic patients infected with Omicron.

Progressive residual lung abnormalities as final outcome in recovered severe COVID-19 pneumonia with lung function abnormalities in spirometry: Pulmonologist and radiologist perspective

ABSTRACT Coronavirus coronavirus-related (severe acute respiratory syndrome-corona virus-2) global pandemic has caused significant mortality and morbidity globally in the last 3 years. Although the pandemic has weaned off since last year, we are not in great peace of relief due to lingering effects of COVID-19 persisted even after 2 years of illness. These long COVID-19 manifestations are documented selected cases of COVID-19 pneumonia in pulmonary and extrapulmonary systems with variable impact on quality of life. In the present case report, a 57-year-old male, presented in the outdoor unit for shortness of breath on exertion, on oxygen supplementation at home during ambulation with a history of severe COVID-19 pneumonia resulted in acute respiratory distress syndrome with hospitalization in the intensive care unit 12 months back and required high flow nasal cannula with noninvasive ventilatory support for 3 weeks. His clinical and radiological severity were very well correlated with highly raised inflammatory markers such as C-reactive protein, interleukin-6, ferritin, lactate dehydrogenase, and D-Dimer. He was offered oxygen supplementation at home with antifibrotics for 3 months and observed significant improvement in clinical and radiological outcomes with persistent requirement of oxygen during ambulation and persistent respiratory symptoms even after 1 year of discharge from hospital. Rheumatological workup documented antinuclear antibody (ANA) and rheumatoid factor positive with inconclusive ANA profile reports. His high-resolution computerized tomography thorax documented at 1 year of discharge from the hospital revealed typical interstitial opacities labeled as progressive residual lung abnormalities (PRLAs) which are predominantly reticular and linear opacities in peripheral parts of lungs with honeycombing within typical pleural-based areas with parenchymal bands and altered lung architecture and decreased lung volume in both lungs. Honeycombing is a typical feature of progressive type of RLAs. We recommend these radiological outcome phenotypes as progressive radiological abnormalities (RLAs) at 1 year should be considered pulmonary fibrosis of unclassified type from a pulmonologist perspective due to pattern and presentation after COVID-19 which is not enrolled into interstitial lung disease classification as of now and progressive pulmonary fibrosis as per radiologists’ perspective due to progressive nature of the disease.

Persistent residual lung abnormalities as final outcome in recovered severe COVID-19 pneumonia with lung function abnormalities in spirometry: Pulmonologist and radiologist perspective

Coronavirus-related (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) global pandemic has caused significant mortality and morbidity globally in the last 3 years. In the present case report, a 51-year-old man presented in the outdoor unit for shortness of breath on exertion with a history of severe coronavirus disease-2019 (COVID-19) pneumonia resulted in acute respiratory distress syndrome with hospitalisation in the intensive care unit 1 year back and required high-flow nasal cannula (HFNC) with noninvasive ventilatory support (NIV) for 2 weeks. He was offered oxygen supplementation at home with antibiotics for 3 months and there was no requirement of oxygen and some respiratory symptoms even after 1 year. His high-resolution computed tomography thorax documented at 1 year of discharge from the hospital revealed typical interstitial opacities labelled as persistent residual lung abnormalities (RLAs) that are predominantly reticular and linear opacities in peripheral parts of lungs without honeycombing within typical pleural-based areas with parenchymal bands and minimally altered lung architecture and preserved lung volume.

Cornea Verticillata – a Rare Complication of Chloroquine Toxicity. Case Report

IntroductionCornea verticillata is characterized by bilateral grayish or golden-brown linear opacities in a typical vortex shape, mainly in the lower segments of the corneal epithelium, without covering the corneal stroma. It is most often associated with taking amiodarone but can be induced by other medications. Chloroquine is commonly used in treatment and prevention of protozoal diseases. Additionally, it has applications in dermatology and rheumatology as an anti-inflammatory agent in collagenosis, rheumatoid arthritis or lupus erythematosus. Its ophthalmic side effects and their management are noteworthy and are briefly summarized in this paper.Material and MethodsWe present a case of a 62-year-old female patient who was referred to the clinic for diagnosis of corneal lesions detected incidentally during a follow-up examination 6 months after starting treatment with chloroquine for rheumatoid arthritis.ResultsThe patient was diagnosed with cornea verticillata and informed that it does not affect visual acuity and is not an indication for changes in therapy. Discontinuation of medication results in partial or, in some cases, complete resolution of changes.DiscussionIt is important to closely monitor patients taking drugs that are known to have ophthalmic side effects for the first time in new indications. We should consider eye side effects when treating systemic disease and recommend screening tests.ConclusionsA baseline ophthalmic examination should be performed on all patients before initiating use of chloroquine. Moreover, chloroquine can lead to permanent loss of visual acuity contributing to bull’s eye maculopathy, which is irreversible.

Three-dimensional ultrashort echo time magnetic resonance imaging in pediatric patients with pneumonia: a comparative study

BackgroundUTE has been used to depict lung parenchyma. However, the insufficient discussion of its performance in pediatric pneumonia compared with conventional sequences is a gap in the existing literature. The objective of this study was to compare the diagnostic value of 3D-UTE with that of 3D T1-GRE and T2-FSE sequences in young children diagnosed with pneumonia.MethodsSeventy-seven eligible pediatric patients diagnosed with pneumonia at our hospital, ranging in age from one day to thirty-five months, were enrolled in this study from March 2021 to August 2021. All patients underwent imaging using a 3 T pediatric MR scanner, which included three sequences: 3D-UTE, 3D-T1 GRE, and T2-FSE. Subjective analyses were performed by two experienced pediatric radiologists based on a 5-point scale according to six pathological findings (patchy shadows/ground-glass opacity (GGO), consolidation, nodule, bulla/cyst, linear opacity, and pleural effusion/thickening). Additionally, they assessed image quality, including the presence of artifacts, and evaluated the lung parenchyma. Interrater agreement was assessed using intraclass correlation coefficients (ICCs). Differences among the three sequences were evaluated using the Wilcoxon signed-rank test.ResultsThe visualization of pathologies in most parameters (patchy shadows/GGO, consolidation, nodule, and bulla/cyst) was superior with UTE compared to T2-FSE and T1 GRE. The visualization scores for linear opacity were similar between UTE and T2-FSE, and both were better than T1-GRE. In the case of pleural effusion/thickening, T2-FSE outperformed the other sequences. However, statistically significant differences between UTE and other sequences were only observed for patchy shadows/GGO and consolidation. The overall image quality was superior or at least comparable with UTE compared to T2-FSE and T1-GRE. Interobserver agreements for all visual assessments were significant and rated “substantial” or “excellent.”ConclusionsIn conclusion, UTE MRI is a useful and promising method for evaluating pediatric pneumonia, as it provided better or similar visualization of most imaging findings compared with T2-FSE and T1-GRE. We suggest that the UTE MRI is well-suited for pediatric population, especially in younger children with pneumonia who require longitudinal and repeated imaging for clinical care or research and are susceptible to ionizing radiation.

Value of deep learning reconstruction of chest low-dose CT for image quality improvement and lung parenchyma assessment on lung window.

To explore the performance of low-dose computed tomography (LDCT) with deep learning reconstruction (DLR) for the improvement of image quality and assessment of lung parenchyma. Sixty patients underwent chest regular-dose CT (RDCT) followed by LDCT during the same examination. RDCT images were reconstructed with hybrid iterative reconstruction (HIR) and LDCT images were reconstructed with HIR and DLR, both using lung algorithm. Radiation exposure was recorded. Image noise, signal-to-noise ratio, and subjective image quality of normal and abnormal CT features were evaluated and compared using the Kruskal-Wallis test with Bonferroni correction. The effective radiation dose of LDCT was significantly lower than that of RDCT (0.29 ± 0.03 vs 2.05 ± 0.65 mSv, p < 0.001). The mean image noise ± standard deviation was 33.9 ± 4.7, 39.6 ± 4.3, and 31.1 ± 3.2 HU in RDCT, LDCT HIR-Strong, and LDCT DLR-Strong, respectively (p < 0.001). The overall image quality of LDCT DLR-Strong was significantly better than that of LDCT HIR-Strong (p < 0.001) and comparable to that of RDCT (p > 0.05). LDCT DLR-Strong was comparable to RDCT in evaluating solid nodules, increased attenuation, linear opacity, and airway lesions (all p > 0.05). The visualization of subsolid nodules and decreased attenuation was better with DLR than with HIR in LDCT but inferior to RDCT (all p < 0.05). LDCT DLR can effectively reduce image noise and improve image quality. LDCT DLR provides good performance for evaluating pulmonary lesions, except for subsolid nodules and decreased lung attenuation, compared to RDCT-HIR. The study prospectively evaluated the contribution of DLR applied to chest low-dose CT for image quality improvement and lung parenchyma assessment. DLR can be used to reduce radiation dose and keep image quality for several indications. • DLR enables LDCT maintaining image quality even with very low radiation doses. • Chest LDCT with DLR can be used to evaluate lung parenchymal lesions except for subsolid nodules and decreased lung attenuation. • Diagnosis of pulmonary emphysema or subsolid nodules may require higher radiation doses.

Evaluation of high-resolution computed tomography findings and associated factors in hypersensitivity pneumonitis

Background/Aim: Hypersensitivity pneumonitis (HP) is a lung disease from inhaling diverse environmental and occupational organic substances, such as fungi, bacteria, birds, and occasionally nonorganic materials. An immune response triggers this condition. A high-resolution chest computed tomography (HRCT) scan is typically performed as part of the initial diagnostic assessment. This study assesses HRCT findings in HP patients and examines associated factors between fibrotic and non-fibrotic patient groups. Methods: This retrospective cross-sectional study encompassed all HP patients monitored between 2010 and 2022. The analysis included data from 117 patients. HRCT findings from the patients were categorized based on fibrosis presence, leading to the division of patients into fibrotic and non-fibrotic groups. Comparative analyses were conducted between these groups. Results: Among the 117 subjects analyzed, 59 (50.4%) were male, and 58 (49.6%) were female. The mean age at diagnosis was 52.1 (13.6) years, ranging from 20 to 81. The non-fibrotic HP group comprised 70 (59.8%) patients, while the fibrotic HP group comprised 47 (40.2%). The most prevalent HRCT findings were ground-glass opacity (90.6%), mosaic attenuation (87.2%), and traction bronchiectasis (50.4%). Statistically significant disparities were observed between non-fibrotic and fibrotic HP groups in terms of HRCT findings: ground-glass opacity, irregular linear opacities, reticulation, traction bronchiectasis, honeycombing, and fibrosis (P=0.024, P&lt;0.001). In contrast, the lymphocyte ratio in bronchoalveolar lavage fluid was 28.78 (16.2) in the non-fibrotic HP group and 14.66 (10.3) in the fibrotic HP group. The fibrotic HP group exhibited a statistically significant lower lymphocyte ratio in bronchoalveolar lavage fluid (P&lt;0.001). Conclusion: HRCT findings are pivotal in HP diagnosis and classification. Computed tomography also assists in delineating the HP classification. This study identified ground-glass opacity and mosaic attenuation as the most prevalent HRCT findings in HP patients. Investigating the connection between fibrosis and prognosis is vital for determining patient outcomes, as fibrosis appears to be the principal determinant.

ROLE OF CT CHEST IN EVALUATION OF PULMONARY MANIFESTATIONS OF COVID-19 RECOVERED CASES

Objective: Pulmonary manifestations may be seen in a number of coronavirus disease 2019 (COVID-19)-recovered the evidence on post-COVID pulmonary sequelae is still limited. Herein, we aim to assess the role of computed tomography (CT) chest in the evaluation of pulmonary manifestations of COVID-19 recovered cases. Methods: We conducted a hospital-based study in the Department of Radiodiagnosis at Government Medical College and Rajindra Hospital Patiala. It included 182 reverse transcriptase-polymerase chain reaction (RT-PCR)-proven COVID-19 patients after they recovered from the disease with at least one negative RT-PCR test and/or clinical recovery. Clinical data and CT findings in the recovery phase were summarized, and the relationship of different clinical parameters with CT severity scores was analyzed. Results: The mean (±standard deviation [SD]) age of patients was 50.2±14.7 years, and 62.6% of them were males. The mean (±SD) symptomatic-scan interval was 33.05±22.27 days. Pulmonary abnormalities were found in the majority of the cases in the recovery phase, that is, 176 patients accounting for 96.7%, while six patients had normal scans. Bilateral involvement was seen in 169 out of 176 patients. Common CT patterns observed were ground glass opacities (90.34%), reticular pattern (81.82%), interlobular septal thickening (70.45%), linear opacities (90.34% cases), fibrous stripes (78.41% cases), and consolidation (36.93%). The mean (±SD) CT severity score of our study subjects was 16.10±7.95. Patients were also categorized into four groups according to symptomatic scan interval &lt;1 month, 1–2 month, 2–3 month, and &gt;3 months. We found that residual changes were more severe in patients with shorter symptomatic scan interval. Conclusion: COVID-19 patients demonstrate persistent pulmonary abnormalities even after clinical recovery. Hence, follow-up in patients with moderate and severe disease is strongly recommended.

Squamous cell carcinoma of lung presenting as “Sunray sign” in chest radiograph

Lung cancer is usually diagnosed at a late stage due to a lack of awareness of symptoms to the patient, absence of screening trends by performing chest imaging, and lack of sensitization to the most common radiological signs of lung malignancy to family physicians. Radiological signs will help in suspecting lung cancer earliest and important role in guiding for a protocolized workup to rule out underlying malignancy. “Sunray sign” in chest radiograph is the first time described in the literature and constitutes hilar mass or radiopacity with inhomogeneous linear opacities spreading toward peripheries like sunrays which is the marker of interstitial lymphatic involvement due to the malignant spread of disease. “Sunray sign” is an indicator of underlying lung malignancy with central airway or mainstem bronchus involvement with lymphatic dissemination in linear opacities. In this case report, we have reported a 51-year male presented with cough and hemoptysis with progressive worsening of shortness of breath. Chest X-ray documented round opacity occupying left hilum with linear opacities emerging toward peripheries in lung parenchyma showing typical “Sunray sign.” Bronchoscopy was done after clinical stabilization and showed endobronchial polypoidal growth in the left mainstem bronchus causing partial occlusion of the bronchial lumen. Endobronchial needle aspiration cytology and forceps-guided histopathology suggestive of “squamous cell” type of lung malignancy for “Sunray sign” in our case. A high index of suspicion is a must to rule out underlying malignancy and Bronchoscopy is a “gold standard” test in cases with Sunray signs to confirm the diagnosis.

Arsenic exposure associated with lung interstitial changes in non-smoking individuals living near a petrochemical complex: A repeated cross-sectional study

Arsenic exposure is associated with airway inflammation and decreased lung function tests. Whether arsenic exposure associated with lung interstitial changes remains unknown. We conducted this population-based study in southern Taiwan during 2016 and 2018. Our study recruited individuals aged over 20 years, residing in the vicinity of a petrochemical complex and with no history of cigarette smoking. In both the 2016 and 2018 cross-sectional studies, we conducted chest low-dose computed tomography (LDCT) scans, as well as urinary arsenic and blood biochemistry analyses. Lung interstitial changes included lung fibrotic changes that were defined as the presence of curvilinear or linear densities, fine lines, or plate opacity in specific lobes; additionally, other interstitial changes were defined as the presence of ground-glass opacity (GGO) or bronchiectasis on the LDCT images. In both cross-sectional studies conducted in 2016 and 2018, participants with lung fibrotic changes exhibited a statistically significant increase in the mean urinary arsenic concentrations compared to those without fibrotic changes (geometric mean = 100.1 vs. 82.8 μg/g creatinine, p < 0.001 for cross-sectional study 2016, and geometric mean = 105.6 vs. 71.0 μg/g creatinine, p < 0.001 for cross-sectional study 2018). After controlling for age, gender, body mass index, platelet counts, hypertension, aspartate aminotransferase, cholesterol, HbA1c, and educational levels, we observed a significant positive association between a unit increase in log urinary arsenic concentrations and the risk of lung fibrotic changes in both cross-sectional study 2016 (odds ratio [OR] = 1.40, 95% confidence interval [CI] = 1.04–1.90, p = 0.028) and cross-sectional study 2018 (OR = 3.03, 95% CI = 1.38–6.63, p = 0.006). Our study did not find a significant association between arsenic exposure and bronchiectasis or GGO. It is imperative for the government to take significant measures to reduce arsenic exposure levels among individuals living near petrochemical complexes.

Postmortem Identification of Vascular Ehlers-Danlos Syndrome in a Lung Transplant Recipient.

Postmortem Identification of Vascular Ehlers-Danlos Syndrome in a Lung Transplant Recipient.

Reticulation Sign on Thin-Section CT: Utility for Predicting Invasiveness of Pure Ground-Glass Nodules.

BACKGROUND. Pure ground-glass nodules (pGGNs) may represent a diverse range of histologic entities of varying aggressiveness. OBJECTIVE. The purpose of this study was to evaluate the use of the reticulation sign on thin-section CT images for predicting the invasiveness of pGGNs. METHODS. This retrospective study included 795 patients (mean age, 53.4 ± 11.1 [SD] years; 254 men, 541 women) with a total of 876 pGGNs on thin-section CT that underwent resection between January 2015 and April 2022. Two fellowship-trained thoracic radiologists independently reviewed unenhanced CT images to assess the pGGNs for a range of features, including diameter, attenuation, location, shape, air bronchogram, bubble lucency, vascular change, lobulation, spiculation, margins, pleural indentation, and the reticulation sign (defined as multiple small linear opacities resembling a mesh or a net); differences were resolved by consensus. The relationship between the reticulation sign and lesion invasiveness on pathologic assessment was evaluated. RESULTS. On pathologic assessment, the 876 pGGNs included 163 nonneoplastic and 713 neoplastic pGGNs (323 atypical adenomatous hyperplasias [AAHs] or adenocarcinomas in situ [AISs], 250 minimally invasive adenocarcinomas [MIAs], and 140 invasive adenocarcinomas [IACs]). Interobserver agreement for the reticulation sign, expressed as kappa, was 0.870. The reticulation sign was detected in 0.0% of nonneoplastic lesions, 0.0% of AAHs/AISs, 6.8% of MIAs, and 54.3% of IACs. The reticulation sign had sensitivity of 24.0% and specificity of 100.0% for a diagnosis of MIA or IAC and sensitivity of 54.3% and specificity of 97.7% for a diagnosis of IAC. In multivariable regression analyses including all of the assessed CT features, the reticulation sign was a significant independent predictor of IAC (OR, 3.64; p = .001) but was not a significant independent predictor of MIA or IAC. CONCLUSION. The reticulation sign, when observed in a pGGN on thin-section CT, has high specificity (albeit low sensitivity) for invasiveness and is an independent predictor of IAC. CLINICAL IMPACT. Those pGGNs that show the reticulation sign should be strongly suspected to represent IAC; this suspicion may guide risk assessments and follow-up recommendations.

Ultra-high resolution CT imaging of interstitial lung disease: impact of photon-counting CT in 112 patients.

To compare lung parenchyma analysis on ultra-high resolution (UHR) images of a photon-counting CT (PCCT) scanner with that of high-resolution (HR) images of an energy-integrating detector CT (EID-CT). A total of 112 patients with stable interstitial lung disease (ILD) were investigated (a) at T0 with HRCT on a 3rd-generation dual-source CT scanner; (b) at T1 with UHR on a PCCT scanner; (c) with a comparison of 1-mm-thick lung images. Despite a higher level of objective noise at T1 (74.1 ± 14.1 UH vs 38.1 ± 8.7UH; p < 0.0001), higher qualitative scores were observed at T1 with (a) visualization of more distal bronchial divisions (median order; Q1-Q3) (T1: 10th division [9-10]; T0: 9th division [8-9]; p < 0.0001); (b) greater scores of sharpness of bronchial walls (p < 0.0001) and right major fissure (p < 0.0001). The scores of visualization of CT features of ILD were significantly superior at T1 (micronodules: p = 0.03; linear opacities, intralobular reticulation, bronchiectasis, bronchiolectasis, and honeycombing: p < 0.0001), leading to the reclassification of 4 patients with non-fibrotic ILD at T0, recognized with fibrotic ILD at T1. At T1, the mean (± SD) radiation dose (CTDI vol: 2.7 ± 0.5mGy; DLP: 88.5 ± 21mGy.cm) was significantly lower than that delivered at T0 (CTDI vol: 3.6 ± 0.9mGy; DLP: 129.8 ± 31.7mGy.cm) (p < 0.0001), corresponding to a mean reduction of 27% and 32% for the CTDIvol and DLP, respectively. The UHR scanning mode of PCCT allowed a more precise depiction of CT features of ILDs and reclassification of ILD patterns with significant radiation dose reduction. Evaluation of lung parenchymal structures with ultra-high-resolution makes subtle changes at the level of the secondary pulmonary lobules and lung microcirculation becoming visually accessible, opening new options for synergistic collaborations between highly-detailed morphology and artificial intelligence. • Photon-counting CT (PCCT) provides a more precise analysis of lung parenchymal structures and CT features of interstitial lung diseases (ILDs). • The UHR mode ensures a more precise delineation of fine fibrotic abnormalities with the potential of modifying the categorization of ILD patterns. • Better image quality at a lower radiation dose with PCCT opens new horizons for further dose reduction in noncontrast UHR examinations.