Morphological Predictors of Primary Lung Cancer among Part-Solid Ground-Grass Nodules on High-Resolution CT

Recent advancements in computed tomography (CT) scanning have improved the detection rates of peripheral pulmonary nodules, including those with ground-glass opacities (GGOs). This study focuses on part-solid pure ground-glass nodules (GGNs) and aims to identify imaging predictors that can reliably differentiate primary lung cancer from nodules with other diagnoses among part-solid GGNs on high-resolution CT (HRCT). A retrospective study was conducted on 609 patients who underwent surgical treatment or observation for lung nodules. Radiological findings from pre-operative HRCT scans were reviewed and several CT imaging features of part-solid GGNs were examined for their positive predictive value to identify primary lung cancer. The proportions of the nodules with a final diagnosis of primary lung cancer were significantly higher in part-solid GGNs (91.9%) compared with solid nodules (70.3%) or pure GGNs (66.7%). Among CT imaging features of part-solid GGNs that were evaluated, consolidation-to-tumor ratio (CTR) < 0.5 (98.1%), pleural indentation (96.4%), and clear tumor border (96.7%) had high positive predictive value to identify primary lung cancer. When two imaging features were combined, the combination of CTR < 0.5 and a clear tumor border was identified to have 100% positive predictive values with a sensitivity of 40.8%. Thus we conclude that part-solid GGNs with a CTR < 0.5 accompanied by a clear tumor border evaluated by HRCT are very likely to be primary lung cancers with an acceptable sensitivity. Preoperative diagnostic procedures to obtain a pathological diagnosis may potentially be omitted in patients harboring such part-solid GGNs.

Misdiagnosis Diagnosis of Pneumocystis Pneumonia as Chemical Pneumonitis

Background

Auxiliaries, a mixed chemicals, for printing and dyeing characterized by their diverse range and complex chemical compositions are commonly utilized in the textile industry. These chemicals can lead to environmental contamination and pose health risks to humans.

Case Description

A 29-year-old man who worked in a printing and dyeing factory in Suzhou, China, reported having tightness in his chest and coughing. Despite seeking medical treatment at several hospitals, the initial diagnosis remained elusive. High-resolution chest CT scans showed multifocal lesions in both lungs. The patient had no significant medical history, and the respiratory symptoms only surfaced after exposure to dyeing auxiliaries. Physicians initially suspected chemical pneumonitis due to occupational exposure. However, a subsequent evaluation at a hospital specializing in occupational diseases led to a diagnosis of AIDS and pneumocystis pneumonia.

Conclusion

This case underscores the importance of comprehensive clinical diagnosis to avoid biases and reduce the incidence of misdiagnosis.

[The value of HRCT in predicting cerebrospinal fluid gusher during cochlear implantation]

Objective:To investigate the predictive value of temporal bone high-resolution CT（HRCT） multiplanar reconstruction（MPR） for cerebrospinal fluid（CSF） gusher during cochlear implantation in patients with inner ear malformation. Methods:The clinical data of 33 patients（36 ears） with inner ear malformation who underwent cochlear implantation were retrospectively analyzed. The predictive value of HRCT for cerebrospinal fluid gusher during cochlear implantation was evaluated. Results:The width of the cochlear foramen（P=0.024, OR=1.735） and the diameter of the inner auditory meatus（P=0.022, OR=6.119） were independent risk factors for CSF gusher during cochlear implantation. The area under the curve（AUC） of cochlear foramen width in predicting intraoperative gusher was 0.851, the sensitivity was 93.33%, and the specificity was 61.90%. The AUC of the upper and lower diameter of the internal auditory canal for predicting intraoperative gusher was 0.848, the sensitivity was 80.00%, and the specificity was 80.95%. The AUC of cochlear foramen width combined with the upper and lower diameters of the internal auditory meatus for predicting intraoperative gusher was 0.930, the sensitivity was 80.00%, and the specificity was 95.24%. Conclusion:Based on temporal bone HRCT, the prediction model of cochlear foramen width combined with the upper and lower diameter of the internal auditory canal has crucial predictive value for the "gusher" during cochlear implantation in patients with inner ear malformation.

Prognostic value of automated assessment of interstitial lung disease on CT in systemic sclerosis

OBJECTIVE

Stratifying the risk of death in SSc-related interstitial lung disease (SSc-ILD) is a challenging issue. The extent of lung fibrosis on high-resolution CT (HRCT) is often assessed by a visual semiquantitative method that lacks reliability. We aimed to assess the potential prognostic value of a deep-learning-based algorithm enabling automated quantification of ILD on HRCT in patients with SSc.

METHODS

We correlated the extent of ILD with the occurrence of death during follow-up, and evaluated the additional value of ILD extent in predicting death based on a prognostic model including well-known risk factors in SSc.

RESULTS

We included 318 patients with SSc, among whom 196 had ILD; the median follow-up was 94 months (interquartile range 73-111). The mortality rate was 1.6% at 2 years and 26.3% at 10 years. For each 1% increase in the baseline ILD extent (up to 30% of the lung), the risk of death at 10 years was increased by 4% (hazard ratio 1.04, 95% CI 1.01, 1.07, P = 0.004). We constructed a risk prediction model that showed good discrimination for 10-year mortality (c index 0.789). Adding the automated quantification of ILD significantly improved the model for 10-year survival prediction (P = 0.007). Its discrimination was only marginally improved, but it improved prediction of 2-year mortality (difference in time-dependent area under the curve 0.043, 95% CI 0.002, 0.084, P = 0.040).

CONCLUSION

The deep-learning-based, computer-aided quantification of ILD extent on HRCT provides an effective tool for risk stratification in SSc. It might help identify patients at short-term risk of death.

Comparison of Radiation Dose and Image Quality of Pediatric High-Resolution Chest CT Between Photon-Counting Detector CT and Energy-Integrated Detector CT: A Matched Study

BACKGROUND. Photon-counting detector (PCD) CT has been shown to reduce radiation dose and improve image quality in adult chest CT examinations; its potential impact in pediatric CT is not well documented. OBJECTIVE. The purpose of our study was to compare radiation dose, objective image quality, and subjective image quality of PCD CT and energy-integrating detector (EID) CT in children undergoing high-resolution CT (HRCT) of the chest. METHODS. This retrospective study included 27 children (median age, 3.9 years; 10 girls, 17 boys) who underwent PCD CT between March 1, 2022, and August 31, 2022, and 27 children (median age, 4.0 years; 13 girls, 14 boys) who underwent EID CT between August 1, 2021, and January 31, 2022; all examinations comprised clinically indicated chest HRCT. The patients in the two groups were matched by age and water-equivalent diameter. Radiation dose parameters were recorded. One observer placed ROIs to measure objective parameters (lung attenuation, image noise, and SNR). Two radiologists independently assessed subjective measures (overall image quality and motion artifacts) using 5-point Likert scales (1 = highest quality). Groups were compared. RESULTS. PCD CT, in comparison with EID CT, showed lower median CTDIvol (0.41 vs 0.71 mGy, p < .001), DLP (10.2 vs 13.7 mGy × cm, p = .008), size-specific dose estimate (0.82 vs 1.34 mGy, p < .001), and tube current-exposure time product (48.0 vs 202.0 mAs, p < .001). PCD CT and EID CT showed no significant difference in right upper lobe (RUL) lung attenuation (mean, -793 vs -750 HU; p = .09), right lower lobe (RLL) lung attenuation (mean, -745 vs -716 HU; p = .23), RUL image noise (mean, 55 vs 51 HU; p = .27), RLL image noise (mean, 59 vs 57 HU; p = .48), RUL SNR (mean, -14.9 vs -15.8; p = .89), or RLL SNR (mean, -13.1 vs -13.6; p = .79). PCD CT and EID CT showed no significant difference in median overall image quality for reader 1 (1.0 vs 1.0, p = .28) or reader 2 (1.0 vs 1.0, p = .17) or median motion artifacts for reader 1 (1.0 vs 1.0, p = .07) or reader 2 (1.0 vs 1.0, p = .22). CONCLUSION. PCD CT showed significantly reduced dose levels without a significant difference in objective or subjective image quality compared with EID CT. CLINICAL IMPACT. These data expand understanding of the capabilities of PCD CT and support its routine use in children.

[Surgical management of 27 cases with temporal bone cerebrospinal fluid leakage]

Objective:To study the clinical manifestations and surgical treatment of temporal bone cerebrospinal fluid leakage. Methods:The clinical data of twenty seven cases with temporal bone cerebrospinal fluid leakage were analyzed retrospectively. Different surgical procedures were adopted according to the location of the leak and the hearing status of the affected ear.If the leakage location was clear before surgery, direct repair was performed via mastoid path or middle cranial fossa path with or without mastoid abdominal fat packing.For patients with unclear leak, large lesion or intractable CEREBROspinal fluid leakage of temporal bone, subtotal petrosal resection and abdominal fat packing were performed.Subtotal temporal bone resection and abdominal fat packing were performed for patients with cochlear involvement. Results:In this study, cases of temporal bone CSF leakage including 13 cases of inner ear malformation; 5 cases secondary to head trauma or previous surgery,5 cases of idiopathic intracranial hypertension or meningocele, 2 cases of langerhans histiocytosis in the temporal bone and 2 cases of inner ear inflammation. High resolution CT （HRCT） of temporal bone showed bone defect of inner auditory canal with vestibular communication in 13 patients with inner ear malformation.The temporal bone HRCT of the remaining 14 patients showed bone defects in the middle cranial fossa or posterior cranial fossa, while MRI of the temporal bone showed meningeal continuity interruption with cerebrospinal fluid inflow into the temporal bone or meningoencephalocele in 12 patients. The 26 patients were followed up from 6 months to 6 years. 1 patient lost follow-up.Meningitis recurred in only 1 patient with inner ear malformation, and subtotal resection of rock bone plus abdominal fat packing was performed.Postoperative hearing was preserved or improved in 7 patients.None of the patients had serious complications, and only 1 patient developed HB Grade Ⅱ facial paralysis after vestibular obliteration, and the facial paralysis recovered within one week. Conclusion:Temporal bone cerebrospinal fluid leakage is relatively rare. Surgical intervention should be taken as early as possible when conservative treatment is failure. Preoperative HRCT and MRI examination are necessary for the localization of the leakage, and individualized surgical approaches can be adopted according to the location of the leakage and the features of the lesion.

[A case of spontaneous middle cranial fossa cerebrospinal fluid leak presenting as recurrent bacterial meningitis]

A 19-year-old man with a history of Chiari type I malformation was admitted to our hospital two times within a 2-month period because of bacterial meningitis. Cerebrospinal fluid (CSF) analysis showed neutrophilic pleocytosis and hypoglycorrhachia. During the second admission, we became aware of hearing loss on the right since age 15 years. High-resolution temporal bone CT showed soft tissue opacification of the right epitympanum and external auditory canal. Tissue biopsy resulted in CSF otorrhea and pneumocephalus. CT cisternography revealed a temporal bone CSF leak. Brain MRI showed a dural defect localized to the anterior petrous apex. Using a combined middle cranial fossa-transmastoid approach, the dural defect and associated arachnoid granulations were located along the superior side of the greater petrosal nerve and repaired. A CSF leak without underlying pathology, such as trauma, surgery, or congenital abnormality, is defined as spontaneous. Spontaneous CSF leak should be considered as a cause of recurrent bacterial meningitis even when CSF otorrhea and fluid behind the tympanic membrane are clinically absent.

High-Resolution CT Findings of Myositis-Related Interstitial Lung Disease

Myositis-related interstitial lung disease presents with a wide variety of lesions, ranging from chronic to acute. It can be divided into two main forms by the types of onsets, namely, chronic to subacute type showing nonspecific interstitial pneumonia (NSIP) or NSIP with an organizing pneumonia (OP)/fibrosing OP (FOP) pattern and acute type showing acute lung injury (ALI) to diffuse alveolar damage (DAD) pattern. Anti-aminoacyl tRNA Synthetase antibody-positive cases mainly show an NSIP or FOP pattern, whereas anti-melanoma differentiation-associated gene 5 antibody-positive cases show ALI to DAD pattern. Bilateral consolidation with or without ground-glass opacification with lower lobe predominance is common as a major pattern in all types, but the distribution or extent is sometimes different. The early detection of findings that indicate a rapid progressive course is vital. Diffuse cranio-caudal distribution and multiple ground-glass opacifications with random distribution might indicate a poorer prognosis.

Location and direction dependence in the 3D MTF for a high-resolution CT system

PURPOSE

The purpose of this study was to quantify location and direction-dependent variations in the 3D modulation transfer function (MTF) of a high-resolution CT scanner with selectable focal spot sizes and resolution modes.

METHODS

The Aquilion Precision CT scanner (Canon Medical Systems) has selectable 0.25 mm or 0.5 mm detectors (by binning) in both the axial (x-y) and detector array width (z) directions. For the x-y and z orientations, detectors are configured (x-y) = 0.5 mm/(z) = 0.5 mm for normal resolution (NR), 0.25/0.5 mm for high resolution (HR), and 0.25/0.25 mm for super high resolution (SHR). Six focal spots (FS1-FS6) range in size from 0.4 (x-y) × 0.5 mm (z) for FS1 to 1.6 × 1.4 mm for FS6. Phantoms fabricated from spherical objects were positioned at radial distances of 0, 4.0, 7.5, 11.0, 14.5, and 18.5 cm. Axial and helical acquisitions were utilized and reconstructed using filtered back projection with the FC18 "Body," FC30 "Bone," and FC81 "Bone Sharp" kernels. The reconstructions were used to measure a 1D slice of the 3D MTF by oversampling the 3D ESF in the axial plane [MTF(f_r ); φ = 0°)], 45° out of the axial plane [MTF(f_r ); φ = 45°)], in the longitudinal direction [MTF(f_r ); φ = 80°)], and along the radial and azimuthal directions within the axial plane.

RESULTS

The MTF(f_r ); φ = 45°) drops to 10% (f₁₀ ) at 1.20, 1.45, and 2.06 mm^-1 for NR, HR, and SHR, respectively, for a helical acquisition with FS1, FC30, and r = 4 cm from the isocenter. The MTF(f_r ); φ = 45°) includes contributions of both the axial-plane MTF (f₁₀  = 1.10, 2.04, and 2.01 mm^-1 ) and the longitudinal MTF (f₁₀  = 1.17, 1.18, and 1.82 mm^-1 ) for the NR, HR, and SHR modes, respectively. For SHR, the axial scan mode showed a 15-25% improvement over helical mode in the longitudinal resolution. Helical pitch, ranging from 0.569 to 1.381, did not appreciably affect the 3D resolution (<2%). The radial MTFs across the axial field of view (FOV) showed dependencies on the focal spot length in z; for example, for SHR with FS2 (0.6 × 0.6 mm), f₁₀ at  r = 11 cm was within 17% of the value at r = 4 cm, but for SHR with FS3 (0.6 × 1.3), the reduction in f₁₀ was 46% from 4 to 11 cm from the isocenter. The azimuthal MTF also decreased as r increased but less so for longer gantry rotation times and smaller focal spot dimensions in the axial plane. The longitudinal MTF was minimally affected (<11%) by position in the FOV and was principally affected by the focal spot length in the z-dimension.

CONCLUSIONS

The 3D MTF was measured throughout the FOV of a high-resolution CT scanner, quantifying the advantages of different resolution modes and focal spot sizes on the axial-plane and longitudinal MTF. Reconstruction kernels were shown to impact axial-plane resolution, imparting non-isotropic 3D resolution characteristics. Focal spot size (both in x-y and in z) and gantry rotation time play important roles in preserving the high-resolution characteristics throughout the field of view for this new high-resolution CT scanner technology.

Quantitative CT Analysis of Small Airway Remodeling in Patients with Chronic Obstructive Pulmonary Disease by a New Image Post-Processing System

Purpose

To explore a practical marker for quantitatively analyzing the small airway remodeling in COPD by HRCT.

Patients and Methods

Twenty-four patients with COPD (GOLD I, n = 7; GOLD II, n = 8; GOLD III+IV, n = 9) and 14 healthy controls (7 normal pulmonary function; 7 small-airway disease (SAD)) were enrolled in the study as five groups, GOLD I, GOLD II, GOLD III+IV, normal and SAD. All subjects underwent HRCT and spirometry. With ISP 9.0, whole emphysema index (EI) and the airway parameters, including wall area (WA), lumen area (LA), airway area (AA) of the 3rd, 5th and 9th generations of bronchi, were measured successively. The ratio of LA/AA and WA/AA in the 3rd, 5th and 9th generations of bronchi were calculated and compared among groups.

Results

For the five groups, EI was increased only in GOLD III+IV group (P < 0.05), while the ratio of LA/AA (9-LA/AA) and WA/AA (9-WA/AA) in 9th generation of bronchi have significantly changed since SAD group (P < 0.05). There were significant correlation between FEV₁generations of bronchi (r3 = 0.429, r5 = 0.583, r9 = 0.592, respectively, P < 0.05); FEV₁% and WA/AA (r3 = –0.428, r5 = –0.532, r9 = –0.570, respectively, P < 0.05); as well as MMEF% and LA/AA (r3 = 0.421, r5 = 0.566, r9 = 0.610, respectively, P < 0.05); MMEF% and WA/AA (r3 = –0.421, r5 = –0.529, r9 = –0.593, respectively, P < 0.05).

Conclusion

Small airway remodeling has occurred in the early stage of COPD, while emphysema in the late stage of COPD. The 9-LA/AA and 9-WA/AA are accurate and practical markers for small airway remodeling of COPD.

SARS-CoV-2: what it is, how it acts, and how it manifests in imaging studies

COVID-19 is a disease with many clinical, biochemical, and radiological signs that has a predilection for the lungs, probably because of the high number of ACE-2 receptors in this organ. The infection of cells activates proinflammatory substances, causing diffuse alveolar damage, which is the histopathological basis of ARDS. The exudative phase would manifest as ground-glass opacities and consolidation, and the proliferative phase would manifest as a tendency toward a more linear morphology. Both CT and PET/CT findings support the inflammatory character of the lung lesions in the initial phase of the disease and in patients with mild-moderate disease. Severe cases have pulmonary hypoperfusion that is likely due to abnormal alveolar ventilation and perfusion. On the other hand, a prothrombotic state increases the risk of thromboembolic disease through the activation of coagulation and platelet pathways with the production of fibrin degradation products (D-dimer) and consumption of platelets.

Early clinical and CT features of COVID-19 and community-acquired pneumonia from a fever observation ward in Ningbo, China

INTRODUCTION

We aimed to compare the early clinical manifestations, laboratory results and chest computed tomography (CT) images of coronavirus disease 2019 (COVID-19) patients with those of other community-acquired pneumonia (CAP) patients to differentiate COVID-19 before reverse transcription-polymerase chain reaction results are obtained.

METHODS

The clinical and laboratory data and chest CT images of 51 patients were assessed in a fever observation ward for evidence of COVID-19 between January and February 2020.

RESULTS

24 patients had laboratory-confirmed COVID-19, whereas 27 individuals had negative results. No statistical difference in clinical features was found between COVID-19 and CAP patients except for diarrhoea. There was a significant difference in lymphocyte and eosinophil counts between COVID-19 and CAP patients. 22 (91.67%) COVID-19 patients had bilateral involvement and multiple lesions according to their lung CT images; the left lower lobe (87.50%) and right lower lobe (95.83%) were most often affected, and all lesions were located in peripheral zones of the lung. The most common CT feature of COVID-19 was ground-glass opacity, found in 95.83% of patients, compared to 66.67% of CAP patients.

CONCLUSION

Diarrhoea, lymphocyte counts, eosinophil counts and CT findings (e.g. ground-glass opacity) could help to distinguish COVID-19 from CAP at an early stage of infection, based on findings from our fever observation ward.

A woman with dyspnea and recurrent pneumothorax: when dyspnea is not asthma

Lymphangioleiomyomatosis (LAM) is a rare disease characterized by cystic lung lesions, lymphatic abnormalities, and angiomyolipomas. It can take a significant amount of time to diagnose LAM due to the vague symptoms of fatigue, progressive dyspnea, pneumothorax, and pleural effusion. We present a case of a 29-year-old woman with recurrent spontaneous pneumothorax and progressive dyspnea who was initially misdiagnosed with asthma and was later found to have LAM. As with all rare diagnoses, there needs to be a suspicion of the disease in order for a further workup to be initiated. In patients with a compatible High-resolution CT scan of the chest, a high vascular endothelial growth factor-D (VEGF-D) value is diagnostic for LAM, and no other confirmatory test is needed.

Lung ultrasound B-lines and serum KL-6 correlate with the severity of idiopathic inflammatory myositis-associated interstitial lung disease

OBJECTIVE

Idiopathic inflammatory myositis-associated interstitial lung disease (IIM-ILD) significantly increases morbidity and mortality. Lung ultrasound B-lines and Krebs von den Lungen-6 (KL-6) are identified as new sonographic and serum markers of ILD, respectively. The aim of our work was to assess the role of B-lines and KL-6 as markers of the severity of IIM-ILD. For this purpose, the correlation among B-lines score, serum KL-6 levels, high-resolution CT (HRCT) score, and pulmonary function tests were investigated in IIM-ILD patients.

METHODS

Thirty-eight patients with IIM-ILD underwent chest HRCT scans, lung ultrasound and pulmonary function tests (independently performed within 1 week) examination. To assess severity and extent of ILD at HRCT, the Warrick score was used. The B-lines score denoting the extension of ILD was calculated by summing the number of B-lines on a total of 50 scanning sites. Serum KL-6 levels (U/ml) was measured by chemiluminescent enzyme immunoassay.

RESULTS

A significant correlation was found between the B-lines score and serum KL-6 levels (r = 0.43, P < 0.01), and between the Warrick score and serum KL-6 levels (r = 0.45, P < 0.01). A positive correlation between B-lines score and the Warrick score (r = 0.87, P < 0.0001) was also confirmed. Both B-lines score and KL-6 levels inversely correlated to diffusion capacity for carbon monoxide (r = -0.77, P < 0.0001 and r = -0.42, P < 0.05, respectively) and total lung capacity (r = -0.73, P < 0.0001 and r = -0.36, P < 0.05, respectively). Moreover, B-lines correlated inversely with forced vital capacity (r = -0.73, P < 0.0001), forced expiratory volume in 1 s (r = -0.69, P < 0.0001).

CONCLUSION

B-lines score and serum KL-6 levels correlate with HRCT findings and pulmonary function tests, supporting their use as measures of IIM-ILD severity.

Role of PET/CT in Management of Early Lung Adenocarcinoma

OBJECTIVE. The purpose of this study was to explore the value of FDG PET combined with high-resolution CT (HRCT) in predicting the pathologic subtypes and growth patterns of early lung adenocarcinoma. MATERIALS AND METHODS. A retrospective analysis was conducted on the PET/CT data on ground-glass nodules (GGNs) resected from patients with stage IA lung adenocarcinoma. The efficacy of PET maximum standardized uptake value (SUV_max) combined with HRCT signs in prediction of histopathologic subtype and growth pattern of lung adeno-carcinoma was evaluated. RESULTS. SUV_max was significantly higher in GGNs with invasive HRCT signs. The diameter of GGN (odds ratio, 1.660; p = 0.000) and the difference in attenuation value (odds ratio, 1.012; p = 0.011) between ground-glass components and adjacent lung tissues were independent predictors of FDG uptake by GGNs. SUV_max was higher in invasive adenocarcinoma than in adenocarcinoma in situ (AIS)-minimally invasive adenocarcinoma (MIA) (median SUV_max, 2.0 vs 1.1; p = 0.008). An SUV_max of 2.0 was the optimal cutoff value for differentiating invasive adenocarcinoma from AIS-MIA. Acinar-papillary adenocarcinoma had a higher SUV_max than lepidic adenocarcinoma (median SUV_max, 2.1 vs 1.3; p = 0.037). An SUV_max of 1.4 was the optimal cutoff value for differentiating the growth pattern of adenocarcinoma. Use of PET/CT with HRCT significantly improved efficacy for differentiating invasive adeno-carcinoma from AIS-MIA. However, use of HRCT cannot significantly improve the diagnostic efficacy of FDG PET in the evaluation of tumors with different growth patterns. CONCLUSION. FDG PET can be used to predict the histopathologic subtypes and growth patterns of early lung adenocarcinoma. Combined with HRCT, it has value for predicting invasive histopathologic subtypes but no significance for predicting invasive growth patterns.

High-Resolution CT Change over Time in Patients with Idiopathic Pulmonary Fibrosis on Antifibrotic Treatment

Antifibrotic treatment slows down functional decline and disease progression in idiopathic pulmonary fibrosis (IPF). High-resolution computed tomography (HRCT) is useful to diagnose IPF; however, little is known about whether and to what extent HRCT changes reflect functional changes during antifibrotic therapy. The aim of this study was, therefore, to assess HRCT change over time after 1 year of treatment and to evaluate whether these changes correlate with functional decline over the same period of time. Sixty-eight IPF patients on antifibrotic treatment (i.e., pirfenidone or nintedanib) were functionally categorized as stable or progressors based on whether (or not) they had a decline in forced vital capacity (FVC) >5% predicted/year, and their HRCT were scored blindly and independently by two expert thoracic radiologists at treatment initiation (HRCT1) and after 1 year of treatment (HRCT2). Ground glass opacities (Alveolar Score, AS), reticulations (Interstitial Score, IS) and honeycombing (HC) were quantified and correlated with FVC decline between HRCT1 and HRCT2. At treatment initiation, HRCT scores were similar in both stable patients and progressors. After one year of treatment, in the entire population, AS and HC increased significantly, while IS did not. However, when stratified by the rate of functional decline, in stable patients, HC increased significantly while AS and IS did not. On the other hand, among progressors AS and HC increased significantly whereas IS did not. In the entire population, the combined score of fibrosis (IS + HC) correlated significantly with FVC decline. In conclusion, IPF patients on antifibrotic treatment exhibit different patterns of HRCT change over time based on their rate of functional decline. HRCT data should be integrated to lung function data when assessing response to antifibrotic treatment in patients with IPF.

Lung Adenocarcinoma Manifesting as Ground-Glass Opacity Nodules 3 cm or Smaller: Evaluation With Combined High-Resolution CT and PET/CT Modality

OBJECTIVE. The purpose of this study is to evaluate high-resolution CT (HRCT) combined with PET/CT for preoperative differentiation of invasive adenocarcinoma (IAC) from preinvasive lesions and minimally invasive adenocarcinoma (MIA) (the combination of which is hereafter referred to as preinvasive-MIA) in lung adenocarcinoma manifesting as ground-glass opacity nodules (GGNs) 3 cm or smaller. MATERIALS AND METHODS. We retrospectively analyzed the data of patients with lung adenocarcinoma with GGNs that were 3 cm or smaller between November 2011 and November 2018. The HRCT and PET/CT parameters for GGNs were compared to differentiate between IAC and preinvasive-MIA. Qualitative and quantitative parameters were analyzed using univariate and multivariate logistic regression models. The diagnostic performance of different parameters was compared using ROC curves and the McNemar test. RESULTS. The study enrolled 89 patients (24 men and 65 women) with lung adenocarcinoma who had a mean (± SD) age of 60.1 ± 8.1 years (range, 36-78 years). The proportions of mixed GGN type, polygonal or irregular shape, lobulated or spiculated edge, and dilated, distorted, or cutoff bronchial sign were higher for IAC GGNs than for preinvasive-MIA GGNs, and the attenuation value of the ground-glass opacity component on CT (CT_GGO), maximum standardized uptake value, and the standardized uptake value (SUV) index (i.e., the ratio of the tumor maximum SUV to the liver mean SUV) for IAC GGNs were also higher (p = 0.001-0.022). Logistic regression analyses showed that the CT_GGO and SUV index were independent predictors for IAC GGNs. The accuracy of CT_GGO in combination with the SUV index for predicting IAC was 81.4% on a per-GGN basis and 85.4% on a per-patient basis. The combined HRCT and PET/CT modality had higher sensitivity and accuracy than did morphologic features, HRCT, and PET/CT measurement parameters alone (p < 0.001). CONCLUSION. The combined HRCT and PET/CT modality is an effective method to preoperatively identify IAC in lung adenocarcinoma manifesting as GGNs 3 cm or smaller.

[A modern approach to the diagnosis of nasal liquorrhea]

Nasal liquorrhea is cerebrospinal fluid leakage from cerebrospinal fluid spaces of the cerebral cavity into the nasal cavity or paranasal sinuses due to congenital or acquired abnormalities of the skull base bones and meninges of various etiologies. The severity of liquorrhea varies from hidden manifestations to profuse leakage of cerebrospinal fluid from the nasal cavity. The diagnosis of overt nasal liquorrhea is not problematic, but the diagnosis of latent liquorrhea is a challenge. In this case, the disease leads to potentially fatal complications, such as meningitis (the risk amounts to 10-37%), pneumocephaly, pneumonia, etc. These peculiarites give rise to two main tasks: early diagnosis confirming liquorrhea and accurate identification of the CSF fistula location when planning further surgical management.

PURPOSE

The study purpose was to review and comparatively analyze all modern methods of diagnosing nasal liquorrhea as well as to substantiate the most effective and promising approaches and algorithms.

MATERIAL AND METHODS

The study included papers in English and Russian found in the Pubmed database and related to the diagnosis of basal liquorrhea of different etiology and localization.

RESULTS

This review demonstrates that diagnostic tests vary widely in sensitivity, specificity, accuracy, invasiveness, and cost. Given all the criteria, detection of beta-2 transferrin or beta-trace protein is the best method for confirming nasal liquorrhea, and high-resolution computed tomography is the best technique for localization of the abnormality.

CONCLUSION

Based on the review, we suggest a diagnostic algorithm for nasal liquorrhea. However, the evidence presented in this review is unfortunately not very reliable, which indicates the existing need for more accurate studies.

Anatomical study of presigmoid-retrolabyrinthine approach based on temporal bone high-resolution CT

BACKGROUND

The surgical approach of acoustic neuroma includes translabyrinthine, transcranial fossa, suboccipital retrosigmoid sinus, and presigmoid retrolabyrinthine approach. Aims/Objective: To provide the anatomical basis for the surgical selection of presigmoid retrolabyrinthine approach by measuring the anatomical parameters of retrolabyrinthine space of the petrous bone by high-resolution CT.

MATERIAL AND METHODS

A retrospective study of 208 high-resolution CT (HRCT) images of 104 patients examined in our hospital were analyzed retrospectively. Forty-nine males and 55 females were included in this study. Lines were drawn on the HRCT to measure the morphological data for pre-operational assessment.

RESULT

Morphological data were retracted from HRCT, for preoperational assessment.

CONCLUSION AND SIGNIFICANCE

Using the standard postprocessing images of temporal bone HRCT can predict the size of the retrolabyrinthine space and the degree of exposure to the inner auditory canal, providing an important anatomical index for the choice of presigmoid retrolabyrinthine approach.

Superior Canal Dehiscence: A Comparative Postmortem Multislice Computed Tomography Study

Objective

Superior canal dehiscence is defined by missing bony coverage of the superior canal against the middle cranial fossa. The gold standard in diagnosis is high-resolution computed tomography (CT). A false-positive CT scan, identifying a dehiscence when one is not present, could lead to unnecessary surgical therapy. This study aims to compare postmortem CT scans with autopsy findings with regard to superior canal dehiscence.

Study Design

Postmortem study.

Setting

Tertiary referral center.

Subjects and Methods

Twenty-two nontraumatic death cases within a 3-month period (January to March 2017) were included with 44 temporal bones. Each body underwent postmortem head CT prior to medicolegal autopsy. The middle fossa floor was exposed, and if present, the superior semicircular canal dehiscence was identified and measured. In each case, 3 comparable photographs were taken during the autopsy (left temporal bone, right temporal bone, overview).

Results

Autopsy findings revealed bony dehiscences in 11% of the temporal bones, whereas CT scan revealed bony dehiscences in 16%. The length of the dehiscences were longer when measured by CT imaging.

Conclusion

The diagnosis of superior canal dehiscence syndrome requires high-resolution CT with clinical symptoms and physiologic evidence of a third mobile window. Our study underlines a mismatch between multislice CT imaging in the coronal plane and the presence of a dehiscence on autopsy.

High-Resolution CT Findings of Obstructive and Restrictive Phenotypes of Chronic Lung Allograft Dysfunction: More Than Just Bronchiolitis Obliterans Syndrome

OBJECTIVE

The purpose of this article is to review the high-resolution CT characteristics of individual obstructive and restrictive chronic lung allograft dysfunction (CLAD) phenotypes to aid in making accurate diagnoses and guiding treatment.

CONCLUSION

Long-term survival and function after lung transplant are considerably worse compared with after other organ transplants. CLAD is implicated as a major limiting factor for long-term graft viability. Historically thought to be a single entity, bronchiolitis obliterans syndrome, CLAD is actually a heterogeneous group of disorders with distinct subtypes.

Imaging of Cystic Fibrosis and Pediatric Bronchiectasis

1. CT is superior to pulmonary function tests and chest radiography for the assessment and monitoring of cystic fibrosis (CF)-related lung disease and, also, of pediatric bronchiectasis not caused by CF (hereafter referred to as non-CF bronchiectasis). 2. Low-dose CT protocols that impart radiation doses similar to those used in chest radiography are feasible for the surveillance of patients with bronchiectasis. 3. Chest radiography is still most commonly used as the first-line imaging examination of choice for the assessment of acute complications related to bronchiectasis. 4. Pulmonary MRI, with or without the use of inhaled hyperpolarized gas, can be performed to obtain functional information, and, in dedicated centers, it may yield imaging results comparable to those obtained by CT. 5. Gastrointestinal and pancreaticobiliary manifestations of CF are observed with greater frequency in adults, because of increased life expectancy.

The comparison of high-resolution computed tomography findings in asbestosis and idiopathic pulmonary fibrosis

BACKGROUND

To determine whether the HRCT findings are useful to differentiate asbestosis from idiopathic pulmonary fibrosis (IPF).

METHODS

We assessed HRCT scans from patients with asbestosis (n = 96) and IPF (n = 65). The frequencies and extent of parenchymal abnormalities and the frequencies of pleural changes were evaluated by consensus of two chest radiologists.

RESULTS

There was a significant difference between IPF and asbestosis in pleural changes. In addition, there were significant differences between IPF and asbestosis in several parenchymal abnormalities on CT, especially in the less advanced stage of both diseases. On multivariate analysis, HRCT features that distinguished asbestosis from IPF were subpleural lines at a distance of less than 5 mm from the inner chest wall, subpleural dots and parenchymal bands.

CONCLUSIONS

There are significant differences between IPF and asbestosis in the parenchymal and pleural abnormalities on CT.

Multimodality thoracic imaging of juvenile systemic sclerosis: emphasis on clinical correlation and high-resolution CT of pulmonary fibrosis

OBJECTIVE. Juvenile systemic sclerosis is a rare multisystem autoimmune disorder characterized by vasculopathy and multiorgan fibrosis. Cardiopulmonary complications are the leading cause of morbidity and mortality. Although pulmonary fibrosis is the complication that is most common and well described, cardiovascular and esophageal involvement may also be observed. In this article, common thoracic findings in juvenile systemic sclerosis will be discussed. We will focus on chest CT, including CT findings of pulmonary fibrosis and associated grading methods, as well as cardiac MRI and esophageal imaging. CONCLUSION. Radiologists play a pivotal role in the initial diagnosis and follow-up evaluation of pediatric patients with systemic sclerosis. Treatment decisions and prognostic assessment are directly related to imaging findings along with clinical evaluation.

Middle East respiratory syndrome coronavirus (MERS-CoV) infection: chest CT findings

OBJECTIVE

The purpose of this study was to describe the chest CT findings in seven patients with Middle East respiratory syndrome coronavirus (MERS-CoV) infection.

CONCLUSION

The most common CT finding in hospitalized patients with MERS-CoV infection is that of bilateral predominantly subpleural and basilar airspace changes, with more extensive ground-glass opacities than consolidation. The subpleural and peribronchovascular predilection of the abnormalities is suggestive of an organizing pneumonia pattern.

Elemental analysis of occupational and environmental lung diseases by electron probe microanalyzer with wavelength dispersive spectrometer

Occupational and environmental lung diseases are a group of pulmonary disorders caused by inhalation of harmful particles, mists, vapors or gases. Mineralogical analysis is not generally required in the diagnosis of most cases of these diseases. Apart from minerals that are encountered rarely or only in specific occupations, small quantities of mineral dusts are present in the healthy lung. As such when mineralogical analysis is required, quantitative or semi-quantitative methods must be employed. An electron probe microanalyzer with wavelength dispersive spectrometer (EPMA-WDS) enables analysis of human lung tissue for deposits of elements by both qualitative and semi-quantitative methods. Since 1993, we have analyzed 162 cases of suspected occupational and environmental lung diseases using an EPMA-WDS. Our institute has been accepting online requests for elemental analysis of lung tissue samples by EPMA-WDS since January 2011. Hard metal lung disease is an occupational interstitial lung disease that primarily affects workers exposed to the dust of tungsten carbide. The characteristic pathological findings of the disease are giant cell interstitial pneumonia (GIP) with centrilobular fibrosis, surrounded by mild alveolitis with giant cells within the alveolar space. EPMA-WDS analysis of biopsied lung tissue from patients with GIP has demonstrated that tungsten and/or cobalt is distributed in the giant cells and centrilobular fibrosing lesion in GIP. Pneumoconiosis, caused by amorphous silica, and acute interstitial pneumonia, associated with the giant tsunami, were also elementally analyzed by EPMA-WDS. The results suggest that commonly found elements, such as silicon, aluminum, and iron, may cause occupational and environmental lung diseases.

HRCT score in bronchiectasis: correlation with pulmonary function tests and pulmonary artery pressure

BACKGROUND:

High-resolution CT scan (HRCT) and its score have an important role in delineating pathological changes and pulmonary functional impairment in patients with bronchiectasis.

AIMS:

To assess pulmonary function tests (PFTs) in patients with cystic and cylindrical bronchiectasis. To correlate HRCT score with PFTs and systolic pulmonary artery pressure (SPAP) in both radiological types.

MATERIALS AND METHODS:

A cross-sectional study of patients with bronchiectasis diagnosed by HRCT was conducted at King Khalid University Hospital, Riyadh, Saudi Arabia. PFTs, HRCT score and SPAP were measured in both types.

RESULTS:

We studied 94 patients with bronchiectasis; 62 were cystic and 32 were cylindrical. Their mean age was 53.4 ± 17.5 SD years. Forced vital capacity (FVC%) and forced expiratory volume in 1 second (FEV1%) were significantly lower in cystic patients (P < 0.0001) as compared with cylindrical patients; and diffusion capacity of carbon monoxide (DLCO%) was also significantly lower (P < 0.01). In the cystic group, PaO₂ was significantly lower; and PaCO₂, higher (P < 0.0001). HRCT score was correlated with FEV1% (r = −0.51). HRCT score was significantly lower in the cystic group (P = 0.002) and correlated with SPAP (r = 0.23). Global HTCT score of 10.3 ± 2.5 was associated with SPAP ≥40 mm Hg (P = 0.011).

CONCLUSION:

Patients with cystic bronchiectasis have significantly higher impairment of pulmonary physiology as compared with those with cylindrical bronchiectasis patients. HRCT score correlated with PFTs and SPAP.