Thoracic Computed Tomography Examinations Research Articles

Evaluation of Barium sulfate-copper breast radiation shield for use in thoracic Computed Tomography Examinations

Evaluation of Barium sulfate-copper breast radiation shield for use in thoracic Computed Tomography Examinations

Anatomical Variations in Fissure of the Lung on Computed Tomography

Objective: Lung fissures embryologically separate the bronchopulmonary segments from each other. We aimed to detect anatomical variations in fissures in patients who underwent thoracic computed tomography (CT). Materials and Methods: All the patients underwent a thoracic CT examination between July 1 - July 15, 2022. The patients’ gender, lung fissures continuity, accessory fissures presence, and variation side were recorded. The frequency of fissures was compared between the genders using the chi-square test. Results: The study included a total of 352 patients (211 men, 141 women). A total of 105 variations were detected in 95/352 (26.99%) of the patients, 61/211 (28.91%) were male, 34/141 (24.11%) were female. The right oblique fissure was incomplete in nine (2.6%), and the right horizontal fissure was incomplete in 14 (4%) patients and absent in 14 (4%). The left oblique fissure was observed to be incomplete in 16 (4.5%) patients. A total of 52 (14.8%) accessory fissures were detected. Conclusion: In the literature, a wide variety of fissure variations have been reported. Due to this diversity, having good knowledge of the fissure anatomical architecture is essential when performing surgical procedures and interpreting radiological images to clinically identify the location of bronchopulmonary segments.

Incidental findings of soft tissue gas in canine and feline thoracic computed tomographic examinations.

Computed tomography (CT) is a commonly used modality in small animal veterinary medicine. Anecdotally, gas bubbles are frequently identified in small animals undergoing thoracic CT examination. The aim of this retrospective observational study was to record the occurrence and prevalence of vascular and extravascular gas in routine thoracic CT examinations in dogs and cats. Patients with any clinical signs of diseases related tosoft tissue gas were excluded. A total of 84 canine studies and 90 feline studies were included, detecting gas in 66.7% of all studies, with gas more likely to be detected in canine studies (75.0%) than in feline cases (58.9%) (P=0.009). Canine studies were more likely to have gas detected in postcontrast studies than in precontrast studies (P=0.016). Intravascular gas was detected in 65.5% of all included studies (75% canine and 56.7% feline). Extravascular gas was detected in 13.8% of all studies (14.3% canine, 13.3% feline), with gas detected in the vertebral canal of 8.62% of all studies (canine 11.9%, feline 5.56%) and within fascial planes in 5.75% of all studies (canine 2.38%, feline 8.89%). In conclusion, gas bubbles were identified in the majority of canine and feline thoracic CT studies without clinical evidence of a pathologic etiology.

Effectiveness of low tube voltage scan in the exposure dose for lenses during paediatric thoracic CT examination: anthropomorphic phantoms study.

To determine whether using lower-tube voltage reduces the scattered dose for the lens during paediatric thoracic computed tomography (CT). Two paediatric anthropomorphic phantoms (ATOM Phantom, CIRS, Norfolk, Virginia, USA) representing a newborn and 5-year-old were placed on the gantry of CT scanner, and optically stimulated luminescence dosemeters were placed on the left and right lenses, in front of the left and right thyroid glands, in front of the left and right mammary glands, and in front of and behind the mammary gland level and we measured scattered dose of the optically stimulated luminescence dosemeter was compared for each phantom between 80 and 120kVp. Significant differences were observed in the scatter doses for the lens between 80 and 120kVp (p<0.01). Compared with the 120kVp scan, the scatter doses for the lens were ~15-40% lower in newborn and 5-year-olds using the 80kVp scan during paediatric CT.

An improvement of the computational effective diameter measurement in thoracic computed tomography examinations

A method to calculate a corrected effective diameter (DMIL) to more accurately estimate the dose received by a patient in chest computed tomography (CT) examination had been previously proposed. However, the discrepancy between DMIL and water-equivalent diameter (Dw) is still relatively high (i.e. about 6%). Furthermore, the method is still performed manually, so it is laborious and time-consuming. This study aims to improve the corrected effective diameter with bone correction (Deffcorr) and to automatically calculate it. The automated Deffcorr was calculated as the square root of the product of these corrected AP and LAT diameters. The approach was implemented on 30 patients who had undergone chest CT examination with the standard protocol. The results show that the correlation between the Deffcorr and Dw is R2=0.93 with no statistical difference (p&amp;gt;0.05). The automated Deffcorr is 3.1% lower than Dw. While the DMIL is 10.5% higher than Dw and both are statistically different (p&amp;lt;0.05). In conclusion, the new Deffcorr was introduced and the result obtained was closer to Dw than DMIL. This method is simple enough to be used as an alternative method to accurately estimate Dw for radiation dose estimation in clinical chest CT scanning.

The relationship between thoracic CT findings and C-reactive protein and ferritin levels in COVID-19 patients

Aim: In this study, we aimed to establish the relationship between thoracic computed tomography (CT) findings at initial presentation and CRP and ferritin levels in 232 patients diagnosed with COVID-19. &#x0D; Material and Method: 232 patients who were diagnosed with COVID-19 and underwent a thoracic CT examination at our hospital between Apr 2020 and Aug 2021 were enrolled in this study. The study group was selected from among individuals aged 18-45 years without any chronic diseases and comorbidities. The patients' complaints, RT-PCR test results and blood biochemistry values from the medical records system, and CT imaging from the PACS system were reviewed retrospectively. Parenchymal lesions, ground-glass area, consolidation and combination of ground-glass area and consolidation observed on thoracic CT were considered typical findings. Blood samples were analyzed in the laboratory using standard methods. Routine blood tests were performed to measure serum C-reactive protein and ferritin levels. &#x0D; Results: Out of the 232 patients infected with COVID-19, 118 were female and 114 were male. While the mean age of all patients was 34.9, the mean ages of men and women were 34.9 and 35.2, respectively. No significant differences were observed between the ages of patients with and without lung involvement (32.9, 37.9, p=0.903, respectively). CT scan showed typical parenchymal findings in 140 patients out of whom 65 were male and 75 were female. With regard to the morphologic features observed on CT, ground-glass density was the most common (74 patients), followed by a combination of ground-glass density and consolidation (34 patients) and finally consolidation (32 patients). In statistical analysis, no significant differences were found in CRP values between patients with and without lung involvement, whereas a significant difference was noted in ferritin values (p=0.196 and p

Associating Serum IgM, IgA Levels with Thoracic CT Indicators and Pulmonary Function Indexes in Acutely Exacerbated Chronic Obstructive Pulmonary Disease Patients.

Chronic Obstructive Pulmonary Disease (COPD) is a respiratory condition characterized by acute exacerbations and reduced lung function. This study investigates the link between serum markers (Immunoglobulin M (IgM) and Immunoglobulin A (IgA)), thoracic computed tomography (CT) scan findings, and pulmonary function indexes during these episodes, aiming to improve our understanding and identify new diagnostic indicators. From the First Affiliated Hospital of Hebei North University, we selected 89 COPD patients experiencing acute exacerbation within the past two years for our Acute Exacerbation Group (AG). Meanwhile, 96 COPD patients, initially treated at the same hospital and currently deemed stable, were chosen for the Stable Group (SG). Both groups underwent serum IgM and IgA tests, thoracic CT examinations, and pulmonary function assessments. In the AG Group, the serum IgM levels were marginally lower than in the Stable Group (SG), though the difference wasn't statistically significant (p = 0.097). Conversely, serum IgA levels in the AG were significantly lower than in the SG (p < 0.001). The AG also showed markedly reduced lung volume, inspiratory lung density, and pulmonary function indexes compared to the SG while having considerably higher values for emphysema index (EI) and air trapping index (ATI) (all p < 0.001). Pearson correlation analysis revealed that lung volume, average inspiratory lung density, and IgA levels had strong positive correlations with one-second forced expiratory volume (FEV1), FEV1/forced vital capacity (FVC), and diffuse carbon monoxide (DLCO) (with respective r-values of 0.824, 0.841, and 0.829; all p < 0.001). In contrast, EI and ATI exhibited significantly negative correlations with FEV1, FEV1/FVC, and DLCO (with r-values ranging from -0.837 to -0.885; all p < 0.001). The assessment of serum IgA combined with thoracic CT parameters offers valuable insights for diagnosing and evaluating acute exacerbations of COPD, presenting a straightforward clinical utility.

Classification of thorax computed tomography findings of Covid-19 patients, their correlation with clinical and laboratory data

Aim: The aim of the study is to classify patients infected with Covid-19 in our population according to the radiological consensus defined by Radiology Society of North America (RSNA) and American College of Radiology (ACR) and to show the relationship of the patients with clinical-laboratory findings.&#x0D; Material and Methods: 127 cases (74 males, 53 females; age range 19-92 years) who applied to Ankara City Hospital with symptoms such as fever, cough and respiratory distress and whose laboratory findings were compatible with Covid-19 were included in our study. The thorax computed tomography (CT) findings of the cases were classified according to the RSNA criteria and their relationship with clinical-laboratory data was statistically evaluated.&#x0D; Results: 47.2% of them had fever, 62.2% cough, 22 dyspnea, 4.7% diarrhea and 28.3% fatigue-malaise symptoms. When the thorax CT findings were evaluated, 55% of the patients had a typical appearance, 21% intermediate appearance, 11% atypical appearance and 13% negative appearance.&#x0D; Conclusion: It is obvious that thoracic CT examination has many advantages in evaluating Covid-19 pneumonia. However, it was concluded that more observations should be made in order to classify the findings better and to reveal their relationship with clinical-laboratory findings.

The effect of main pulmonary artery diameter on the prognosis of COVID-19 patients in the ICU

Aim: The aim of this study was to examine the effect of main pulmonary artery diameter (MPAD), which is evaluated in patients when first admitted to the intensive care unit due to COVID-19, on mortality.&#x0D; Material and Method: Thoracic computed tomography examinations performed during the initial admission to hospital of patients who were treated in the intensive care unit between October 1, 2020, and June 1, 2021, were evaluated retrospectively. Cox regression analysis was performed with the program R-Project to evaluate the relationship between MPAD and mortality.&#x0D; Results: No significant correlation was found between MPAD and mortality in models used with or without adjusting for age and sex (respectively P: 0.890 and P: 0.920). &#x0D; Conclusion: The MPAD value measured at the initial admission of COVID-19 patients hospitalized in the intensive care unit is not a parameter that can be used to predict mortality.

Correlations Between Body Weight and Size-Specific Dose Estimate on Thoracic Computed Tomography Examination

The dose received by a patient on CT examination is expressed in size-specific dose estimates (SSDE) which is a function of the patient diameter, x-ray attenuation, and scanner output (volume computed tomography dose index, CTDIvol). Patient diameter and x-ray attenuation are represented as water equivalent diameter (Dw). We conducted the research to analyze the relationships between body weight and Dw, CTDIvol, and size-specific dose estimates (SSDE) in contrast-enhanced thorax examinations. We used images from 100 patients (50 women and 50 men patients) whose weight range from 2.8 kg to 80 kg. The values of Dw, CTDIvol, and SSDE were automatically calculated from axial CT images using the IndoseCT software. Statistical analysis showed that the patient's body weight correlates linearly with the Dw. The linearity coefficient (R2) values for body weight and Dw is 0.43 (women) and 0.55 (men). However, weight was independent of the patient dose in terms of CTDIvol and SSDE. This was because the CT system used tube current modulation (TCM), which automatically adapted the tube current to patient size, resulting in a relatively constant dose regardless of the patient size (Dw).

Anomalies of the aortic arch in dogs: evaluation with the use of multidetector computed tomography angiography and proposal of an extended classification scheme

BackgroundCongenital anomalies of the aortic arch are important as they may be associated with vascular ring anomalies. The most common vascular ring anomaly in dogs is a persistent right aortic arch. However, published data of the distribution of the different types of vascular ring anomalies and other aortic arch anomalies are lacking. The objective of this retrospective descriptive study was to evaluate both the prevalence and the different types of aortic arch anomalies that can be detected using thoracic computed tomography (CT) examination. Archived thoracic CT examinations acquired between 2008 and 2020 at a single institution were retrospectively evaluated by 2 evaluators for the prevalence and type of aortic arch anomaly. Breed, age, and presenting complaint were obtained from the medical record system.ResultsA total of 213 CT studies were evaluated; 21 dogs (21/213, 9.9%) showed a right aortic arch and a left ligamentum arteriosum with compression of the esophagus. The following incidental additional findings were detected: aberrant left subclavian artery (17/21, 76.2%), branching from the persistent ductus arteriosus (PDA) (1/21, 4.8%), left-sided brachiocephalic trunk (3/21, 14.3%), bicarotid trunk (17/21, 81.0%), double aortic arch (1/21, 4.8%). One hundred ninety two dogs (192/213, 90.1%) showed a left aortic arch without esophageal compression. The following additional abnormalities were obtained in those dogs with left aortic arch: aberrant right subclavian artery (3/192, 1.6%) without clinical signs of esophageal compression, aberrant vessel branching from the aorta into the left caudal lung lobe (2/192, 1.0%), focal dilatation of the left or right subclavian artery (2/192, 1.0%), bicarotid trunk (1/192, 0.5%).ConclusionSimilar to previous studies an aberrant left subclavian artery is the most common additional finding in dogs with persistent right aortic arch. Newly, a left-sided brachiocephalic trunk was identified in 14.3% of the dogs with a persistent right aortic arch; no additional compression was caused by the left sided brachiocephalic trunk. Similarly, aberrant right subclavian artery can be an incidental CT finding without causing compression of the esophagus.

Three artificial intelligence data challenges based on CT and ultrasound

Purpose: The 2020 edition of these Data Challenges was organized by the French Society of Radiology (SFR), from September 28 to September 30, 2020. The goals were to propose innovative artificial intelligence solutions for the current relevant problems in radiology and to build a large database of multimodal medical images of ultrasound and computed tomography (CT) on these subjects from several French radiology centers. Materials and methods: This year the attempt was to create data challenge objectives in line with the clinical routine of radiologists, with less preprocessing of data and annotation, leaving a large part of the preprocessing task to the participating teams. The objectives were proposed by the different organizations depending on their core areas of expertise. A dedicated platform was used to upload the medical image data, to automatically anonymize the uploaded data. Results: Three challenges were proposed including classification of benign or malignant breast nodules on ultrasound examinations, detection and contouring of pathological neck lymph nodes from cervical CT examinations and classification of calcium score on coronary calcifications from thoracic CT examinations. A total of 2076 medical examinations were included in the database for the three challenges, in three months, by 18 different centers, of which 12% were excluded. The 39 participants were divided into six multidisciplinary teams among which the coronary calcification score challenge was solved with a concordance index > 95%, and the other two with scores of 67% (breast nodule classification) and 63% (neck lymph node calcifications).

Evaluation of systemic involvement of Coronavirus disease 2019 through spleen; size and texture analysis

Background/aimTo investigate the changes in the spleen size, parenchymal heterogeneity, and computed tomography (CT) texture analysis features of patients diagnosed with Coronavirus disease 2019 (COVID-19)Materials and methodsThe size and parenchymal structure of the spleen in 91 patients who underwent thoracic CT examination due to COVID-19 were evaluated. For the evaluation of parenchymal heterogeneity, CT texture analysis was performed using dedicated software (Olea Medical, France). The texture analysis of each case consisted of 15 first-order intensity-based features, 17 gray level co-occurrence matrix-based features, and 9 gray level run length matrix-based features.ResultsA total of 91 patients (45 males, 46 females) with a mean age of 54.31 ± 16.33 years (range: 18–81) were included in the study. A statistically significant decrease in spleen size was seen in the follow-up CT examinations (p < 0.001) whereas no statistically significant difference was found between the Hounsfield unit (HU) values. The radiomics consisted of first-order intensity-based features such as 90th percentile, maximum, interquartile range, range, mean absolute deviation, standard deviation, and variance, all of which showed statistically significant differences (p - values: < 0.001, < 0.001, 0.001, 0.003, 0.001, 0.001, and 0.004, respectively). “Correlation” as a gray level co-occurrence matrix-based feature and “gray level nonuniformity” as a gray level run length matrix-based feature showed statistically differences (p-values: 0.033 and < 0.001, respectively).ConclusionsAlthough COVID-19 manifests with lung involvement in the early stage, it can also cause systemic involvement, and the spleen may be one of its target organs. A decrease in the spleen size and parenchymal microstructure changes can be observed in the short follow-up time. It is hoped that the changes in the parenchymal microstructure will be demonstrated by a noninvasive method: texture analysis.

Clinical and diagnostic imaging findings in dogs with atrial appendage aneurysm: 7 cases (2014–2020)

Introduction/ObjectiveAtrial appendage aneurysm in dogs is a rare condition and has not been well described. The aim of this study is to describe clinical and diagnostic imaging findings, especially computed tomography (CT), of atrial appendage aneurysms in dogs. AnimalsSeven client-owned dogs with a presumptive diagnosis of left or right atrial appendage aneurysm. Materials and methodsRetrospective study. Medical records were searched to identify dogs with a presumptive diagnosis of left (LAAA) or right atrial appendage aneurysm (RAAA). Signalment, history, examination findings, diagnostic test results, and imaging procedures were reviewed. Archived diagnostic images were retrieved and evaluated by two board-certified radiologists and a board-certified cardiologist. Data analysis was descriptive. ResultsSix cases were diagnosed with RAAA and one with LAAA with a median age of 8 years. Five affected dogs were small to medium-breed male dogs. All dogs underwent a thoracic CT examination for various reasons and all cases of RAAA were incidental findings. CT was useful to identify and assess the atrial appendage aneurysm, as well as neighboring structures, although possible pericardial defects could not be visualized. Five dogs had a concurrent echocardiographic examination, which successfully identified the LAAA and two RAAA. ConclusionsThis case series described the clinical and CT findings in seven dogs with atrial appendage aneurysm, as well as echocardiographic findings in five of these cases. Right atrial appendage aneurysms appear to be mainly incidental findings. CT seems to be more sensitive than echocardiography in the detection of atrial appendage aneurysm.

Incidental diagnosis of Covid-19 pneumonia on chest computed tomography

PurposeThe purpose of this study was to determine the prevalence and imaging characteristics of incidentally diagnosed COVID-19 pneumonia on computed tomography (CT). Materials and methodsThis retrospective study was conducted between March 20th and March 31st, 2020 at Cochin hospital, Paris France. Thoracic CT examinations of all patients referred for another reason than a suspicion of SARS-CoV-2 infection were reviewed. CT images were analyzed by a chest radiologist to confirm the presence of findings consistent with COVID-19 pneumonia and quantify disease extent. Clinical and biological data (C-reactive protein serum level [CRP] and white blood cell count) of patients with CT findings suggestive for COVID-19 pneumonia were retrieved from the electronic medical chart. ResultsDuring the study period, among 205 diagnostic CT examinations, six examinations (6/205, 3%) in 6 different patients (4 men, 2 women; median age, 57 years) revealed images highly suggestive of COVID-19 pneumonia. The final diagnosis was confirmed by RT-PCR. Three inpatients were suspected of extra thoracic infection whereas three outpatients were either fully asymptomatic or presented with fatigue only. All had increased CRP serum level and lymphopenia. Disease extent on CT was mild to moderate in 5/6 patients (83%) and severe in 1/6 patient (17%). ConclusionCumulative incidence of fortuitous diagnosis if COVID-19 pneumonia did not exceed 3% during the highest pandemic phase and was predominantly associated with limited lung involvement.

Targeted radiation energy modulation using Saba shielding reduces breast dose without degrading image quality during thoracic CT examinations

ObjectiveBreasts dose during thoracic computed tomography examinations is a serious challenge and practical dose reduction strategies is needed. The bismuth shielding is an available method for dose reduction; however, its use is on debate due to degrading effects on image quality. The aim of this study is to explore and evaluate the efficiency of a new composition of the X-ray absorbing material to achieve a shield with a lower impact on image quality. Materials and MethodsDifferent shields were manufactured with combinations of various weight percentage of copper and bismuth. Dose reduction ratio and image quality were evaluated in phantom studies. A controlled trial with 20 female participants was conducted for image quality assessment. The shield with a lower impact on image quality, named Saba shielding, was used in the clinical trial. ResultsShielding by one (1 T) and three thickness (3 T) of the constructed shields reduced the mean entrance skin dose of breasts about 52% and 73%, respectively. The shield with a composition of 90% Cu and 10% Bi (Saba shielding) had the lowest while the shield with 100% bismuth had the highest degrading effect on image quality. The Saba shielding could provide 21% higher dose reduction than the Bi shielding at the equivalent image quality. The 1 T Saba shielding did not cause artifacts in the reconstructed images. ConclusionThe Saba shielding is flexible, cheap and user-friendly for shielding breasts in thoracic CT examinations while do not have the degrading effect of the Bi shielding on image quality.

Tracheal diverticula: A retrospective analysis of patients referred for thoracic CT.

To assess the prevalence of tracheal diverticula (TD) in patients referred for thoracic Computed Tomography (CT).1679 consecutive patients subjected to thoracic CT examination for different causes, from January to June 2017, were included in this cohort study. CT was performed with a 64 slice CT, using a standard protocol and Multiplanar Reformat Images (MPR). A TD was defined as a thin-walled air sac at the paratracheal wall with a communication with the tracheal lumen. Congenital or acquired nature of TD was determined by the anatomical location, being usually the congenital ones located 4 to 5 cm below the vocal cords or a few centimeters above the carina in the right paratracheal area, whereas acquired ones were located at the level of the thoracic inlet, in the posterolateral tracheal wall. Presence of TD was assessed and their number and size recorded based on 2 axial diameters and size of neck.One or more TD were found in 96 patients (5.7% of sample), with a slight preponderance (65%) in male gender. Globally, 124 TD were detected; they were solitary in 75% of cases, double in 20.8%, and in about 4.2% they were triple. Average size of the TD was 1.3×4.9 mm with a mean width of the neck of 1.9 mm. The peak of prevalence (9%) was in patients belonging to the fourth-decade group (see Table 1Table 1Distribution of TD in our patients according to age. ). According to their anatomical location, the majority (97.6%) of TD were acquired in nature and devoided of specific symptoms (see below).Acquired TD were detected in about 1 out of 20 of thoracic CTs and were usually incidentally. Our findings show a slightly higher frequency than previously reported. The most frequent presentation was in male and as a single entity. Clinically, TD was not associated with specific symptoms, in particular with chronic cough or Chronic Obstructive Pulmonary Disease (COPD).

Incidental Cardiac Findings in Non–Electrocardiogram-gated Thoracic Computed Tomography of Intensive Care Unit Patients: Assessment of Prevalence and Underreporting

Cardiac findings frequently remain unreported on non-electrocardiogram (ECG)-gated computed tomography (CT). Although the clinical relevance of such findings may be limited in a general patient population, they may have significant impact in intensive care patients. Thus, the purpose of this study was to evaluate the prevalence, underreporting, and clinical relevance of incidental cardiac findings in intensive care unit (ICU) patients. Non-ECG-gated chest CT examinations of ICU patients were retrospectively analyzed for incidental cardiac findings. The findings were classified into 3 categories (A to C): category A findings, which carry potential for risk to life; category B findings, which have a potential for significant morbidity; category C findings, which have a possible effect on prognosis. A total of 500 patients who underwent non-ECG-gated thoracic CT examinations were included. Of the 500 patients, 403 presented with 1443 cardiac findings. Of all cardiac findings, 37% were described in the initial written report. Sixty category A findings were detected, of which 48% were not mentioned in the report. Six hundred forty category B findings were detected, of which 77% were not described in the report. The remaining 743 findings were classified as category C, 55% of which were not reported in the report. The prevalence as well as the rate of underreporting of incidental cardiac findings in non-ECG-gated chest CT of ICU patients is very high. The results of this study underscore the importance of dedicated training for assessment of cardiac structures and conditions, which may be detected on non-ECG-gated chest CT.

Retrospective evaluation of thoracic computed tomography findings in dogs naturally infected by Angiostrongylus vasorum.

Angiostrongylus vasorum (A. vasorum) is an important emerging disease of canidae. Cardiorespiratory signs are common in affected dogs, therefore thoracic imaging is critical for diagnosing and monitoring disease. Descriptions of thoracic computed tomography (CT) findings in dogs naturally infected with A. vasorum are currently lacking. Aims of this multicenter, retrospective study were to describe thoracic CT findings in a group of dogs with confirmed disease, determine whether any changes were consistent among dogs, and propose standardized terms for describing thoracic CT findings. Nine UK-based referral centers' clinical and imaging databases were searched for dogs that had a confirmed diagnosis of A. vasorum, and had undergone thoracic CT examination. Eighteen dogs, from seven of the centers, fulfilled the inclusion criteria. The lung lobes were divided into the following three zones and the CT changes described in each: pleural (zone 1), subpleural (zone 2), and peribronchovascular (zone 3). The predominent abnormality was increased lung attenuation due to poorly defined ground-glass opacity or consolidation. There were regions of mosaic attenuation due to peripheral bronchiectasis. Nine/18 (50%) dogs showed hyperattenuating nodules of varying sizes with ill-defined margins. The distribution always affected zones 1 and 2 with varied involvement of zone 3; this resulted in clear delineation between zones 2 and 3. Tracheobronchial lymphadenomegaly was frequently noted. Findings were nonspecific and there was considerable overlap with other pulmonary conditions. However, authors recommend that A. vasorum be considered a likely differential diagnosis for dogs with a predominantly peripheral distribution of lung changes.

Effective Dose and Size Specific Dose Estimation with and without Tube Current Modulation for Thoracic Computed Tomography Examinations: A Phantom Study

Effective Dose and Size Specific Dose Estimation with and without Tube Current Modulation for Thoracic Computed Tomography Examinations: A Phantom Study