Underwent Chest Computed Tomography Research Articles

The association between clinical laboratory data and chest CT findings explains disease severity in a large Italian cohort of COVID-19 patients

BackgroundLaboratory data and computed tomography (CT) have been used during the COVID-19 pandemic, mainly to determine patient prognosis and guide clinical management. The aim of this study was to evaluate the association between CT findings and laboratory data in a cohort of COVID-19 patients.MethodsThis was an observational cross-sectional study including consecutive patients presenting to the Reggio Emilia (Italy) province emergency rooms for suspected COVID-19 for one month during the outbreak peak, who underwent chest CT scan and laboratory testing at presentation and resulted positive for SARS-CoV-2.ResultsIncluded were 866 patients. Total leukocytes, neutrophils, C-reactive protein (CRP), creatinine, AST, ALT and LDH increase with worsening parenchymal involvement; an increase in platelets was appreciable with the highest burden of lung involvement. A decrease in lymphocyte counts paralleled worsening parenchymal extension, along with reduced arterial oxygen partial pressure and saturation. After correcting for parenchymal extension, ground-glass opacities were associated with reduced platelets and increased procalcitonin, consolidation with increased CRP and reduced oxygen saturation.ConclusionsPulmonary lesions induced by SARS-CoV-2 infection were associated with raised inflammatory response, impaired gas exchange and end-organ damage. These data suggest that lung lesions probably exert a central role in COVID-19 pathogenesis and clinical presentation.

Bronchiectasis is one of the indicators of severe coronavirus disease 2019 pneumonia.

Bronchiectasis is one of the indicators of severe coronavirus disease 2019 pneumonia.

Can Common Lead Apron in Testes Region Cause Radiation Dose Reduction during Chest CT Scan? A Patient Study.

Background: Computed tomography (CT) is a routine procedure for diagnosing using ionization radiation which has hazardous effects especially on sensitive organs.Objective: The aim of this study was to quantify the dose reduction effect of lead apron shielding on the testicular region during routine chest CT scans.Material and Methods: In this measurement study, the routine chest CT examinations were performed for 30 male patients with common lead aprons folded and positioned in testis regions. The patient’s mean body mass index (BMI) was 26.2 ± 4.6 kg/m2. To calculate the doses at testis region, three thermoluminescent dosimeters (TLD-100) were attached at the top surface of the apron as an indicator of the doses without shielding, and three TLDs under the apron for doses with shielding. The TLD readouts were compared using SPSS software (Wilcoxon test) version 16.Results: The radiation dose in the testicular regions was reduced from 0.46 ± 0.04 to 0.20 ± 0.04 mGy in the presence of lead apron shielding (p < 0.001), the reduction was equal to 56%. Furthermore, the heritable risk probability was obtained at 2.0 ×10-5 % and 4.6 ×10-5 % for the patients using the lead apron shield versus without shield, respectively. Conclusion: Applying common lead aprons as shielding in the testis regions of male patients undergoing chest CT scans can reduce the radiation doses significantly. Therefore, this shield can be recommended for routine chest CT examinations.

Chest computed tomography for outcome prediction in laboratory-confirmed COVID-19: A retrospective analysis of 38,051 cases

BACKGROUND:In the current epidemiological situation, computed tomography (CT) of chest organs plays an important role in disease diagnosis. Clinical and CT data allow physicians to quickly establish the probability of the presence and prognosis of patients with coronavirus disease 2019 (COVID-19).&#x0D; AIMS:This study aimed to predict outcomes in patients with laboratory-confirmed COVID-19 based on chest CT and a semi-quantitative visual pulmonary lesion grading system (CT 04).&#x0D; MATERIALS AND METHODS:A retrospective analysis of the Unified Medical Information and Analytical Service and Unified Radiological Information Service records from March 01, 2020 to July 30, 2020 was performed. The inclusion criteria were as follows: patients diagnosed with U07.1 (laboratory-verified coronavirus infection) from March 01, 2020 to July 30, 2020 and referred for a chest CT by a physician with suspected community-acquired pneumonia caused by COVID-19; the maximum period between laboratory verification and CT was not more than five days. The observation period for each patient was at least till 30 days from the date of CT. CT was performed in 48 medical organizations providing primary medical care to adults in Moscow. The exclusion criterion was a negative reverse transcription-polymerase chain reaction results by July30, 2020. The CT 04 scale is recommended for use in the Russian Federation to estimate the volume of lung parenchyma lesions when COVID-19 is suspected.&#x0D; RESULTS:The total sample volume was 38,051 patients. In this study, the risk of death was three times higher for CT-4 than for CT-0. In the KaplanMeier survival curve, the survival rate of patients in the CT-3 category was almost three times lower (hazard ratio = 2.94) than in the CT 02 categories; in addition, the higher the initial category of CT, the lower the risk of deterioration. The time for hospitalization decreased with the increase in the CT grade.&#x0D; CONCLUSION:The visual CT 04 scale can be used to predict outcomes, such as hospitalizations and deaths, in patients suspected of COVID-19 who underwent chest CT in primary health care.

Men and women affected by Sars-CoV-2 pneumonia: same CT features but different outcome

AIMTo compare the computed tomography (CT) features of Sars-CoV-2 pneumonia between the two sexes and among different age groups.MATERIALS AND METHODSConsecutive patients (n=331) who presented to the emergency department and underwent chest CT and reverse transcription polymerase chain reaction (RT-PCR) with a time interval <7 days, which were subsequently found to be consistent with Sars-CoV-2 infection, were enrolled retrospectively. Two experienced radiologists evaluated the images in consensus, recording the number of pulmonary lobes with ground-glass opacities and with consolidation. A CT score was subsequently calculated based on the percentage involvement of each lobe. Clinical symptoms, comorbidities, and level of required hospitalisation were noted. In-hospital mortality was recorded and analysed via the Kaplan–Meier estimator.RESULTSMales and females had the same age distribution. No statistically significant difference was found in the analysed CT features and in the CT score (p=0.31) between the sexes. More females were affected by two or more comorbidities (17.1% versus 7.5%, p=0.024), all comorbidities except diabetes were more prevalent in females. Women had a higher probability to be discharged home and a lower probability to be admitted to the intensive care unit (ICU; p=0.008), in-hospital mortality was inferior (13.5% versus 22%).CONCLUSIONDespite more comorbidities, women had lower hospital admission and mortality, which was independent of CT findings between both sexes.

Abstract 17356: Cardiovascular Findings on Chest Computed Tomography Predict Clinical Outcomes in COVID-19

Background: Computed tomography (CT) chest is routinely used for the diagnosis and management of COVID-19 patients. Though COVID-19 disease-specific pulmonary findings have been well described, the significance of concomitant cardiovascular findings on chest CT are less studied. We examined the presence of various cardiovascular findings as markers for predicting significant outcomes in COVID-19. Methods: A retrospective cohort study was conducted on 163 patients with confirmed COVID-19 who underwent chest CT. In addition to the reported pulmonary findings, specific cardiovascular CT variables were collected, including right and left ventricular dimensions, pulmonary artery and aortic size, reflux of contrast into the IVC, septal position, coronary artery and aortic calcifications. Multivariable analysis was used to determine whether cardiovascular findings predict a composite outcome consisting of in-hospital and 30-day mortality, Intensive Care Unit admission, intubation, extracorporeal membrane oxygenation, proning, and renal replacement therapy. Results: Among our cohort, aortic calcification significantly predicted an increased risk of the composite outcome (odds ratio (OR) 4.73, p &lt; 0.0001). Larger RV diameter predicted composite outcome (OR 1.08, p &lt; 0.01). RV/LV ratio &gt; 0.9 (normal ratio &lt; 0.9) showed borderline significant trend towards 30-day mortality (OR 1.12, p &lt; 0.05). A combination of cardiac findings to discriminate between patients at higher or lower risk of a negative outcome (AUC 0.67, 95% CI 0.57 - 0.76) was non-inferior to a combination of pulmonary CT findings (AUC 0.68, 95% CI 0.6 - 0.76, p = 0.81). Discussion: Our data suggest that cardiovascular findings such as a dilated right ventricle and aortic calcification are important imaging markers in symptomatic patients with COVID-19. These findings highlight the importance of right ventricular parameters and vascular disease in predicting adverse clinical outcomes in these patients. Conclusions: Cardiovascular findings should be recognized and reported when imaging patients with COVID-19. Future, higher-power analyses of long-term outcomes in our cohort are anticipated to yield further results.

Comparison of Contrast Enhanced Magnetic Resonance Angiography to Computed Tomography in Detecting Pulmonary Arteriovenous Malformations.

Background: Computed tomography (CT) is considered the imaging modality of choice to diagnose pulmonary arteriovenous malformations PAVMs. The drawback of this technique is that it requires ionizing radiation. Magnetic resonance (MR) imaging does not have the limitation, but little is known about the performance of MR compared to CT for the detection of PAVMs. The aim of this study is to investigate the sensitivity of contrast-enhanced MR angiography (CE-MRA) in the detection of PAVMs with feeding artery diameters (FAD) > 2 mm. Methods: Patients with a grade 2 or 3 shunt on screening transthoracic contrast echocardiography (TTCE) were asked to participate. Included patients underwent chest CT and CE-MRA. CT was considered the reference standard. CT and CE-MRA scans were anonymized and assessed for the presence of PAVMs with FAD > 2 mm by one and two readers respectively. Data analysis was performed on per patient and per PAVM basis. Results: Fifty-three patients were included. 105 PAVMs were detected on CT, 45 with a FAD ≥ 2 mm. In per patient analysis, sensitivity and specificity of CE-MRA were 92% and 97% respectively for reader 1 and 92% and 62% for reader 2. Negative and positive predictive value (NPV/PPV) were 93% and 96% for R1 and 90% and 67% for R2. In per PAVM analysis, sensitivity, specificity, NPV and PPV were 96%, 99%, 100% and 86% for R1 and 93%, 96%, 100% and 56% for R2, respectively. Conclusions: CE-MRA has excellent sensitivity and NPV for detection of PAVMs with FAD ≥ 2 mm and can therefore be used to detect these PAVMs. We are hopeful that future advancements in CE-MRA technology will reduce false positive rates and allow for more broad use of CE-MRA in PAVM diagnosis and management.

Differentiating synchronous double primary lung adenocarcinomas from intrapulmonary metastasis by CT features, EGFR mutations and ALK rearrangement status.

BackgroundDifferentiating synchronous double primary lung adenocarcinoma (SDPLA) from interpulmonary metastasis (IPM) has significant therapeutic and prognostic implications. This retrospective study aimed to investigate the potential of computed tomography (CT) features and two known oncogenic driver mutations [epidermal growth factor receptor (EGFR) and anaplastic large-cell lymphoma kinase (ALK)] to discriminate synchronous double primary lung adenocarcinoma from one primary pulmonary adenocarcinoma with intrapulmonary metastasis.MethodsPatients with SDPLA were selected at our hospital, and those with IPM served as the control group. All 60 patients (40 with SDPLA and 20 with IPM) were tested for EGFR mutations and ALK status, and they underwent chest CT prior to any treatment. Independent-sample Student’s t-test was used for comparisons between two groups of normally distributed variables, and the Chi-square test was used to compare categorical variables.ResultsThe discordance rate of EGFR mutations was significantly higher in patients with SDPLA than in patients with IPM (40% vs. 5%, P<0.001). The incidence of ALK-positive status was 15%, and patients with IPM were more likely to be ALK-positive than patients with SDPLA (35% vs. 5%, P<0.001). Compared to IPM, SDPLA more frequently occurred in different lobes (P=0.024), presented with less lymphadenopathy (P=0.014), showed a smaller difference in diameter (Äd) between tumors (P=0.001) and more commonly presented as lobulated tumors (P<0.001), spiculated masses (P<0.001), ground-glass opacities (GGOs) (P=0.001) and air bronchograms (P=0.020).ConclusionPatients with SDPLA showed higher discordance with EGFR mutations and were less frequently ALK-positive than those with IPM. Thus, the CT characteristics are significantly different between SDPLA and IPM.

Three-dimensional printing technology for localised thoracoscopic segmental resection for lung cancer: a quasi-randomised clinical trial

BackgroundThree-dimensional (3D) computed tomography (CT) reconstruction technology has gained attention owing to its potential in locating ground glass nodules in the lung. The 3D printing technology additionally allows the visualisation of the surrounding anatomical structure and variations. However, the clinical utility of these techniques is unknown. This study aimed to establish a lung tumour and an anatomical lung model using 3D printing and 3D chest CT reconstruction and to evaluate the clinical potential of 3D printing technology in uniportal video-assisted thoracoscopic segmentectomy.MethodsEighty-nine patients with ground glass nodules who underwent uniportal video-assisted thoracoscopic segmentectomy were classified into the following groups: group A, lung models for pre-positioning and simulated surgery that were performed with 3D chest CT reconstruction and 3D printing, and group B, patients who underwent chest CT scans with image enhancement for 3D reconstruction. The differences in the surgery approach transfer rate, surgical method conversion rate, operative time, intraoperative blood loss, and postoperative complication rate were compared between the two groups.ResultsBetween groups A and B, there were significant differences in the approach transfer rate (0% vs.10.5%, p = 0.030), operative time (2.07 ± 0.24 h vs. 2.55 ± 0.41 h, p < 0.001), intraoperative blood loss volume (43.25 ± 13.63 mL vs. 96.68 ± 32.82 mL, p < 0.001) and the rate of surgical method conversion to lobectomy (0% vs. 10.5%, p < 0.030). In contrast, there was an insignificant difference in the postoperative complication rate between groups A and B (3.9% vs. 13.2%, p = 0.132).Conclusions3D printing technology facilitates a more accurate location of nodules by surgeons, as it is based on two-dimensional and 3D image-based findings, and therefore, it can improve surgical accuracy and safety. This technique is worth applying in clinical practice.

Radiomics-based model for accurately distinguishing between severe acute respiratory syndrome associated coronavirus 2 (SARS-CoV-2) and influenza A infected pneumonia.

Clinicians have been faced with the challenge of differentiating between severe acute respiratory syndrome associated coronavirus 2 (SARS‐CoV‐2) infected pneumonia (NCP) and influenza A infected pneumonia (IAP), a seasonal disease that coincided with the outbreak. We aim to develop a machine‐learning algorithm based on radiomics to distinguish NCP from IAP by texture analysis based on computed tomography (CT) imaging. Forty‐one NCP and 37 IAP patients admitted from January to February 6, 2019 admitted to two hospitals in Wenzhou, China. All patients had undergone chest CT examination and blood routine tests prior to receiving medical treatment. NCP was diagnosed by real‐time RT‐PCR assays. Eight of 56 radiomic features extracted by LIFEx were selected by least absolute shrinkage and selection operator regression to develop a radiomics score and subsequently constructed into a nomogram to predict NCP with area under the operating characteristics curve of 0.87 (95% confidence interval: 0.77‐0.93). The nomogram also showed excellent calibration with Hosmer‐Lemeshow test yielding a nonsignificant statistic (P = .904). The novel nomogram may efficiently distinguish between NCP and IAP patients. The nomogram may be incorporated to existing diagnostic algorithm to effectively stratify suspected patients for SARS‐CoV‐2 pneumonia.

Correlation between Chest Computed Tomography and Lung Ultrasonography in Patients with Coronavirus Disease 2019 (COVID-19)

There is growing evidence regarding chest X-ray and computed tomography (CT) findings for coronavirus disease 2019 (COVID-19). At present, the role of lung ultrasonography (LUS) has yet to be explored. The main purpose of this study was to evaluate the correlation between LUS findings and chest CT in patients confirmed to have (positive reverse transcription polymerase chain reaction [RT-PCR]) or clinically highly suspected of having (dyspnea, fever, myasthenia, gastrointestinal symptoms, dry cough, ageusia or anosmia) COVID-19. This prospective study was carried out in the emergency department, where patients confirmed of having or clinically highly suspected of having COVID-19 were recruited and underwent chest CT and concurrent LUS exam. An experienced emergency department physician performed the LUS exam blind to the clinical history and results of the CT scan, which were reviewed by two radiologists in consensus for signs compatible with COVID-19 (bilateral ground-glass opacities in peripheral distribution). A compatible LUS exam was considered a bilateral pattern of B-lines, irregular pleural line and subpleural consolidations. Between March and April 2020, 51 patients were consecutively enrolled. The indication for CT was a negative or indeterminate RT-PCR test (49.0%) followed by suspicion of pulmonary embolism (41.2%). Radiologic signs compatible with COVID-19 were present in 37 patients (72.5%) on CT scan and 40 patients (78.4%) on LUS exam. The presence of LUS findings was correlated with a positive CT scan suggestive of COVID-19 (odds ratio: 13.3, 95% confidence interval: 4.5–39.6, p < 0.001) with a sensitivity of 100.0%, specificity of 78.6%, positive predictive value of 92.5% and negative predictive value of 100.0%. There was no missed diagnosis of COVID-19 with LUS compared with CT in our cohort. The correlation between LUS score and CT total severity score was good (intraclass correlation coefficient: 0.803, 95% confidence interval: 0.60–0.90, p < 0.001). LUS exhibited similar accuracy compared with chest CT in the detection of lung abnormalities in COVID-19 patients.

Analyzing the Early CT findings and Clinical Features of 12 Patients with 2019 Novel Coronavirus Disease (COVID-19) in China

Background: Regarding the outbreak of highly contagious the 2019 Novel Coronavirus (2019-nCoV) in various countries and regions, data have been needed on the early chest CT images and clinical characteristics of the affected patients. Objectives: To explore the early clinical and computed tomography (CT) characteristics of the 2019 Novel Coronavirus Disease (COVID-19) patients to improve the diagnostic level of this contagious respiratory disease. Methods: An analysis retrospectively was implemented on the radiological features and clinical characteristics of 12 patients with COVID-19 who had undergone chest CT scanning in the designated hospital from Jan 23, 2020, to Feb 18, 2020. The clinical data on general information, epidemiological, cardinal symptoms, blood test, and CT imaging characteristics were obtained. Results: According to the relevant diagnostic criteria, the patients were divided into two groups: mild (2 cases), and ordinary type (10 cases). The main symptoms of 2019-nCoV pneumonia were fever (9/12) and cough (8/12) with or without respiratory and other systemic symptoms. The blood test of the patients showed that most of the white blood cell count was normal (10/12), decreased lymphocyte count (6/12), and increased hypersensitive C reactive protein (hs-CRP) (5/12). In the early stage of COVID-19, the chest CT images showed patchy mixed ground-glass opacity (GGO) (8/12), mainly distributed in the periphery and posterior part of both lungs. The internal density of image lesion area was uneven, and lesions primarily manifested as “crazy-paving pattern” (8/12), with grid-like, interlobular septal thickening, thickened bronchovascular bundle and air bronchus sign and multiple fibrosis. A few cases showed pulmonary atelectasis (1/12), bilateral pleural effusion (1/12), no mediastinal or bilateral hilar lymph node enlargement. Conclusions: The clinical characteristics of 2019-nCoV pneumonia are similar to those of common viral pneumonia. The chest CT images may be helpful for the early detection of novel coronavirus pneumonia.

Lobar Distribution of COVID-19 Pneumonia Based on Chest Computed Tomography Findings; A Retrospective Study.

Computed tomography (CT) imaging has quickly found its place as a beneficial tool in the detection of coronavirus disease 2019 (COVID-19). To date, only a few studies have reported the distribution of lung lesions by segment. This study aimed to evaluate the lobar and segmental distribution of COVID-19 pneumonia based on patients' chest CT scan. This was a retrospective study performed on 63 Iranian adult patients with a final diagnosis of COVID-19. All patients had undergone chest CT scan on admission. Demographic data and imaging profile, including segmental distribution, were evaluated. Moreover, a scoring scale was designed to assess the severity of ground-glass opacification (GGO). The relationship of GGO score with age, sex, and symptoms at presentation was investigated. Among included patients, mean age of patients was 54.2 ±14.9 (range: 26 - 81) years old and 60.3% were male. Overall, the right lower lobe (87.3%) and the left lower lobe (85.7%) were more frequently involved. Specifically, predominant involvement was seen in the posterior segment of the left lower lobe (82.5%). The most common findings were peripheral GGO and consolidation, which were observed in 92.1% and 42.9% of patients, respectively. According to the self-designed GGO scoring scale, about half of the patients presented with mild GGO on admission. GGO score was found to be equally distributed among different sex and age categories; however, the presence of dyspnea on admission was significantly associated with a higher GGO score (p= 0.022). Cavitation, reticulation, calcification, bronchiectasis, tree-in-bud appearance and nodules were not identified in any of the cases. COVID-19 mainly affects the lower lobes of the lungs. GGO and consolidation in the lung periphery is the imaging hallmark in patients with COVID-19 infection. Absence of bronchiectasis, solitary nodules, cavitation, calcifications, tree-in-bud appearance, and reversed halo-sign indicates that these features are not common findings, at least in the earlier stages.

Indeterminate pulmonary nodules among patients with new diagnosis of colorectal cancer: Prevalence and significance assessment

Background: In Saudi Arabia, colorectal cancer (CRC) accounts for 11.5% of cancer incidence, where nearly one-third is metastatic. Global guidelines recommend accurate pretreatment staging to determine resectability and stage-directed treatment. Computed tomography (CT) scan is among the widely used imaging for staging. However, at times, the characterization of abnormalities detected by CT scan is perplexing. Indeterminate pulmonary nodules (IPNs) are nodules that are neither benign nor malignant, which are incidentally detected on baseline staging chest CT. We aimed to estimate the prevalence of IPN that were identified among CRC patients. Materials and Methods: We conducted a retrospective record review of all newly diagnosed CRC patients between June 2013 and June 2018 from an academic hospital in Jeddah, Kingdom of Saudi Arabia (KSA). Demographics and certain prespecified variables were collected. The presence of IPN on staging chest CT as per consultant radiologist report was documented, and the ability of other modalities to identify the nature of IPN was compared. Data were analyzed using SPSS and a P value < 0.05 was considered significant. Results: Of 283 CRC patients, 208 (73.5%) underwent chest CT, and the mean age was 57.4 years (±SD 13.1). The prevalence of IPN among CRC patients is 17.7%. Thirty IPN patients had a follow-up chest CT for IPN, which identified IPN nature in 18(60%) of them. The likelihood of IPN to be CRC-related metastasis was significantly associated with the presence of synchronous liver metastasis (P = 0.0005), younger age (P = 0.022), and colon cancer (P = 0.011). Conclusion: The prevalence of IPN was 17.7%, which is different in comparison to other studies from different countries. There is a vital need for unified guidelines describing IPN to accurately stage CRC patients, decrease unnecessary follow-ups, and acquire the exact prevalence of IPN.

Diagnostic test interpretation and referral delay in patients with interstitial lung disease

BackgroundDiagnostic delays are common in patients with interstitial lung disease (ILD). A substantial percentage of patients experience a diagnostic delay in the primary care setting, but the factors underpinning this observation remain unclear. In this multi-center investigation, we assessed ILD reporting on diagnostic test interpretation and its association with subsequent pulmonology referral by a primary care physician (PCP).MethodsA retrospective cohort analysis of patients referred to the ILD programs at UC-Davis and University of Chicago by a PCP within each institution was performed. Computed tomography (CT) of the chest and abdomen and pulmonary function test (PFT) were reviewed to identify the date ILD features were first present and determine the time from diagnostic test to pulmonology referral. The association between ILD reporting on diagnostic test interpretation and pulmonology referral was assessed, as was the association between years of diagnostic delay and changes in fibrotic features on longitudinal chest CT.ResultsOne hundred and forty-six patients were included in the final analysis. Prior to pulmonology referral, 66% (n = 97) of patients underwent chest CT, 15% (n = 21) underwent PFT and 15% (n = 21) underwent abdominal CT. ILD features were reported on 84, 62 and 33% of chest CT, PFT and abdominal CT interpretations, respectively. ILD reporting was associated with shorter time to pulmonology referral when undergoing chest CT (1.3 vs 15.1 months, respectively; p = 0.02), but not PFT or abdominal CT. ILD reporting was associated with increased likelihood of pulmonology referral within 6 months of diagnostic test when undergoing chest CT (rate ratio 2.17, 95% CI 1.03–4.56; p = 0.04), but not PFT or abdominal CT. Each year of diagnostic delay was associated with a 1.8% increase in percent fibrosis on chest CT. Patients with documented dyspnea had shorter time to chest CT acquisition and pulmonology referral than patients with documented cough and lung crackles.ConclusionsDeterminants of ILD diagnostic delays in the primary care setting include underreporting of ILD features on diagnostic testing and prolonged time to pulmonology referral even when ILD is reported. Interventions to modulate these factors may reduce ILD diagnostic delays in the primary care setting.

Improved Detection of Benign and Malignant Rib Lesions in the Routine Computed Tomography Workup of Oncological Patients Using Automated Unfolded Rib Image Postprocessing.

The aim of this study was to evaluate the performance of the automated computed tomography (CT) postprocessing software unfolded rib images for improved detection of both benign and malignant rib lesions during routine diagnostic workup of oncological patients. One thousand eight in-patients and out-patients (63.66 ± 14.25 years; range, 18.67-95.67 years; 405 females and 603 males), undergoing chest CT between July 2018 to January 2019 at our institution, were retrospectively evaluated. Patients underwent chest CT alone or as part of a whole-body CT staging/restaging. The CT protocol consisted of the following: 120 kV; 100 mAs; matrix, 512 × 512; collimation, 0.6 mm; reconstructed section thickness of 3 mm and 1 mm using a soft tissue spatial resolution kernel (I30f) and a sharp kernel (B70f). Both transversal image data sets were used for "conventional" diagnosis including coronal reformates with 3-mm slice thickness. One-millimeter slice thickness image data sets of all patients were additionally directed from the scanner to a computational server where they were automatically postprocessed to 3-dimensional unfolded ribs. The "unfolding" of the rib using the centerline as an axis allows a synchronous display and rotation of all ribs by mouse scrolling. These postprocessed image data sets were evaluated in a separate reading session (approximately 4 weeks later). The readers had no information about the underlying medical history or clinical presentation. They were asked to record the lesion number, site of involvement along the rib (proximal, body, distal), number of the involved ribs, and the character of the lesion in terms of lytic versus sclerotic versus mixed lytic/sclerotic. The standard of reference was F-FDG PET, Ga-DOMITATE PET/CT, bone scan, or imaging follow-up (>6 months). From a total of 1008 evaluated patients, 763 (73.02%) were hemato-oncologic patients. A total of 104 rib lesions were found by transversal CT image reading, whereas the unfolded rib image reading detected 305 lesions. Eighty-nine were classified malignant, and 202 were classified benign. Detection of malignant rib lesions proved significant both for less than 1 cm (P < 0.02) and more than 1 cm in diameter (P < 0.007). The sensitivity, specificity, positive predictive value, and negative predictive value for detection of malignant rib lesions were 97.7%, 98.5%, 96.6%, and 99% for unfolding ribs, and 76.4%, 100%, 92.7%, and 90.5% for conventional (transversal) image reading, respectively. Detection of sclerotic rib lesions and lesions greater than 1 cm in diameter were significantly better (P < 0.01) for the unfolding rib algorithm. The "unfolded rib" reformates are significantly superior for rib lesion detection compared with conventional transversal CT scan reading and should therefore be used in all patients, particularly those with an oncologic background.

Breast exposure reduction using organ-effective modulation on chest CT in Asian women

PurposeOrgan-effective modulation (OEM) is a mechanism to reduce radiation dose to selected organs on computed tomography (CT). The purpose of this study was to measure radiation dose to the breast in Asian patients undergoing chest CT and to clarify the degree of exposure reduction. MethodWe randomly selected 60 female patients undergoing non-contrast chest CT after breast cancer surgery. To measure radiation dose, an optically stimulated luminescence dosimeter had been attached directly to the gown over the nonoperated breast in 30 patients. Radiologists evaluated the image quality with and without OEM. In order to clarify the characteristics of OEM, the effects of angle and object size were measured using a phantom and an ionization chamber dosimeter. ResultsThe OEM group received 9.1 ± 1.9 mGy and the non-OEM group received 10.7 ± 2.4 mGy. OEM reduced the exposure by 12.2% (P < 0.01). OEM caused no reduction in diagnostic quality. In the phantom study, the results of the angle effect were 3.2%, 11.2%, 28.7%, 31.3, 25.9%, 14.9% and 6.0% dose reductions at −90, −60, −30, 0, 30, 60 and 90°, respectively. The effect of the subject thickness was 3.7%, 17.5%, 30.2%, 31.7%, and 34.1% at 16, 20, 24, 28 and 32 cm diameters, respectively. ConclusionsOEM is a useful mechanism for reducing radiation exposure to the breast without affecting diagnostic imaging quality. The reduction rate correlated negatively with body habitus.

Normal lung attenuation distribution and lung volume on computed tomography in a Chinese population.

Backgroud and objectives: Although lung attenuation distribution and lung volume on computed tomography (CT) have been widely used in evaluating COPD and interstitial lung disease, there are only a few studies regarding the normal range of these indices, especially in Chinese subjects. We aimed to describe the normal range of lung attenuation distribution and lung volume based on CT.Methods: Subjects with normal lung function and basically normal chest CT findings (derivation group) at Ruijin Hospital, Shanghai (from January 2010 to June 2014) were included according to inclusion and exclusion criteria. The range of the percentage of lung volume occupied by low attenuation areas (LAA%), percentile of the histogram of attenuation values (Perc n), and total lung volume were analyzed. Relationships of these measures with demographic variables were evaluated. Participants who underwent chest CT examination for disease screening and had basically normal CT findings served as an external validation group.Results: The number of subjects in the derivation group and external validation groups were 564 and 1,787, respectively. Mean total lung volumes were 4,468±1,271 mL and 4,668±1,192 mL, and median LAA%(-950 HU) was 0.19 (0.03–0.43) and 0.17 (0.01–0.41), in the derivation and external validation groups, respectively. Reference equations for lung volume and attenuation distribution (LAA% using -1,000–210 HU, Perc 1 to Perc 98) were generated: Lung volume (mL) = -1.015 *10^4+605.3*Sex (1= male, 0= female)+92.61*Height (cm) –12.99*Weight (kg) ±1766; LAA% (-950 HU)=[0.2027+0.05926*Sex (1= male, 0= female) –4.111*10^-3*Weight (kg) +4.924*10^-3*Height (cm) +8.504*10^-4*Age]^7.341–0.05; Upper limit of normal range: [0.2027+0.05926*Sex-4.111*10^-3*Weight+4.924*10^-3*Height+8.504*10^-4*Age+0.1993]^7.341–0.05.Conclusion: This large population-based retrospective study demonstrated the normal range of LAA%, Perc n, and total lung volume measured on CT scans among subjects with normal lung function and CT findings. Reference equations are provided.

Pulmonary MALT Lymphoma has variable features on CT

Pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma is the most common primary pulmonary lymphoma. There are limited studies on imaging features of pulmonary MALT lymphoma. We present the computed tomography (CT) manifestations of pulmonary MALT lymphoma and the correlation between CT manifestations and clinical characteristics. Patients (n = 53) with histologically confirmed pulmonary MALT lymphoma who underwent chest CT scanning were retrospectively analyzed. Evaluated findings included distribution of pulmonary lesions, morphological pattern of appearance, contrast enhancement features, size, presence of thoracic lymphadenopathy, and secondary associated features. Pulmonary MALT lymphoma was observed in multiple (79%) and bilateral (66%) disease with random distribution (≥70%) of pulmonary lesions. The most frequent morphological pattern was consolidation (n = 33, 62%), followed by nodule (n = 23, 43%) and mass (n = 11, 21%). Common associated features were air bronchograms and bronchiectasis, especially cystic bronchiectasis and angiogram sign. Asymptomatic patients had less consolidation and bronchiectasis than did symptomatic patients. Cystic bronchiectasis was only observed in the symptomatic group. In conclusion, pulmonary MALT lymphoma manifests as diverse patterns on CT scans. Consolidation combined with cystic bronchiectasis was a characteristic late sign, which may assist in differential diagnosis. High-resolution CT images and multiplanar reconstruction techniques are helpful for accurately determining imaging manifestations.

Risk factors associated with an increase in the size of ground-glass lung nodules on chest computed tomography.

BackgroundThe detection rate of ground‐glass nodules (GGNs) in the lung has increased with the increased use of low‐dose computed tomography (CT) of the chest for cancer screening; however, limited data is available on the natural history, follow‐up, and treatment of GGNs. The aim of this study was to identify factors associated with an increase in the size of GGNs.MethodsA total of 338 patients (mean ages, 59.8 years; males, 35.5%) with 689 nodules who underwent chest CT at our institute between June 2004 and February 2014 were included in this study. The cut‐off date of follow‐up was August 2018. We analyzed the size, solidity, number, and margins of the nodules compared with their appearance on previous chest CT images. The Cox proportional hazard model was used to identify risk factors associated with nodule growth.ResultsThe median follow‐up period was 21.8 months. Of the 338 patients, 38.5% had a history of malignancy, including lung cancer (8.9%). Among the 689 nodules, the median size of the lesions was 6.0 mm (IQR, 5–8 mm), and the proportion of nodules with size ≥10 mm and multiplicity was 17.1% and 66.3%, respectively. Compared to the nodules without an increase in size, the 79 nodules with an increase in size during the follow‐up period were initially larger (growth group, 7.0 mm vs. non‐growth group, 6.0 mm; P = 0.027), more likely to have a size ≥10 mm (26.6% vs. 15.9%; P = 0.018), and had less frequent multiplicity (54.4% vs. 67.9%, P = 0.028). In the multivariate analysis, nodule size ≥10 mm (hazard ratio [HR], 2.044; P = 0.005), a patient history of lung cancer (HR: 2.190, P = 0.006), and solitary nodule (HR: 2.499, P < 0.001) were independent risk factors for nodule growth.ConclusionCareful follow‐up of GGNs is warranted in patients with a history of malignancy, a large , or a solitary nodule.