High-resolution CT in smoking-related interstitial lung diseases.

In addition to chronic obstructive pulmonary disease (COPD) and bronchogenic carcinoma, smoking can also cause interstitial lung diseases (ILDs) such as respiratory bronchiolitis (RB), RB with ILD (RB-ILD), desquamative interstitial pneumonia (DIP), Langerhans cell granulomatosis (LCG) and idiopathic pulmonary fibrosis-usual interstitial pneumonia (IPF-UIP). However, smoking seems to have a protective effect against hypersensitivity pneumonitis (HP), sarcoidosis and organising pneumonia (OP). High-resolution computed tomography (HRCT) has a pivotal role in the differential diagnosis. RB is extremely frequent in smokers, and is considered a marker for smoking exposure. It has no clinical relevance in itself since most patients with RB are asymptomatic. It is frequent to observe the association of RB with other smoking-related diseases, such as LCG or pulmonary neoplasms. In RB-ILD, HRCT features are more conspicuous and diffuse than in RB, but there is no definite cut-off between the two entities and any distinction can only be made by integrating imaging and clinical data. RB, RB-ILD and DIP may represent different degrees of the same pathological process, consisting in a bronchiolar and alveolar inflammatory reaction to smoking. Smoking is also a well-known risk factor for pulmonary fibrosis. Multidisciplinary discussion and follow-up can generally solve even the most difficult cases.

Radiological diagnosis of fibrosing interstitial lung diseases: innovations and controversies.

Following the introduction of new effective antifibrotic drugs, interest in fibrosing interstitial lung diseases (FILD) has been renewed. In this context, radiological evaluation of FILD plays a cardinal role. Radiological diagnosis is possible in about 50% of the cases, which allows the initiation of effective therapy, thereby avoiding invasive procedures such as surgical lung biopsy. Usual interstitial pneumonia (UIP) pattern may be diagnosed based on clinical, radiological, and pathological data. High-resolution computed tomography features of UIP have been widely described in literature; however, interpreting them remains challenging, even with specific expertise on the subject. Diagnostic difficulties are understandable given the continuous evolution of FILD classifications and their complexity. Both early-stage diseases and advanced or combined patterns are not easily classifiable, and many end up being labelled 'indeterminate´ or 'unclassifiable´. Especially in these cases, optimal patient management involves collaboration and communication between different specialists. Here, we discuss the most critical aspects of radiological interpretation in FILD diagnosis based on the most recent classifications. We believe that the clinicians´ awareness of radiological diagnostic issues of FILD would improve comprehension and dialogue between physicians and radiologists, leading to better clinical practice.

Correlation Between Renal Cortical Stiffness and Histological Determinants by Point Shear-Wave Elastography in Patients With Kidney Transplantation.

INTRODUCTION: Renal allograft biopsy is the gold standard for the detection of histological lesions of chronic allograft dysfunction. The identification of a noninvasive routine test would be desirable. Elastosonography is used to assess tissue stiffness according to viscosity, and no data are available on the use of point quantification shear-wave elastography (ElastPQ) for the evaluation of renal chronic lesions. RESEARCH QUESTION: To evaluate the feasibility of ElastPQ to assess cortical allograft stiffness and to determine the correlation of clinical, biological, and pathological factors with the diagnostic accuracy of kidney stiffness values in patients with histological lesions. DESIGN: Forty-two patients underwent kidney transplant biopsy and 10 valid measurements of ElastPQ, blindly performed by 2 operators. The interobserver reproducibility was assessed according to intraclass correlation coefficient. The ElastPQ measurements and the clinical data were compared using the Spearman correlation analysis. RESULTS: 97.6% reliable measurements were obtained using ElastPQ, with an excellent interobserver agreement. The kidney stiffness was significantly higher in the patients with a time since transplantation >12 months and was correlated with chronic lesions (interstitial fibrosis, tubular atrophy transplant glomerulopathy, and mesangial matrix), with the interstitial fibrosis/tubular atrophy, score and with the sum of the scores of the chronic lesions. Mesangial matrix increase is the only independent determinant of kidney stiffness. DISCUSSION: ElastPQ is a noninvasive, reproducible, and sensitive diagnostic tool able to detect moderate/severe chronic lesions. Its routine use during follow-up can identify patients eligible for biopsy, which remains the gold standard exam for detecting chronic allograft dysfunction.

Magnetic resonance imaging in the complications of kidney transplantation.

Kidney transplantation is currently the treatment of choice in most patients with end-stage chronic renal failure owing to the excellent results in terms of both graft and patient survival. However, surgical complications are still very frequent. Although urological (stricture, urinary fistulas, vesico-ureteral reflux) and lymphatic complications (lymphocoele) have a high incidence, they only rarely lead to graft loss. By contrast, vascular complications (stenosis, arterial and venous thrombosis, arterio-venous fistulas, pseudoaneurysms) are relatively rare, but potentially serious and may affect graft survival. Finally, medical complications such as acute tubular necrosis (ATN), rejection and de novo neoplasms may also arise in kidney transplantation. The purpose of this pictorial review is to illustrate the increasingly significant contribution of magnetic resonance angiography (MRA) in the management of complications of kidney transplantation, and emphasise how this method should now be considered a mandatory step in the diagnostic workup of selected cases. Moreover, the application and role in this setting of new magnetic resonance imaging (MRI) techniques, such as diffusion-weighted and blood oxygen level-dependent (BOLD) MRI, are also discussed.

Screening for lung cancer using low-dose spiral CT: 10 years later, state of the art.

Ten years after the first papers on this subject, this editorial represents a brief review on lung cancer screening with low-dose spiral CT. The aim is to present the main theoretical and practical problems related to lung cancer screening, the historical background and results of observational studies and the main ongoing randomised controlled trials. In particular, the National Lung Screening Trial (NLST), which was interrupted early, is discussed. The opinion of the authors is that too many questions are still awaiting an answer.

Natural history of honeycombing: follow-up of patients with idiopathic pulmonary fibrosis treated with single-lung transplantation.

PURPOSE: Although honeycombing is one of the key features for the diagnosis of idiopathic pulmonary fibrosis (IPF), its origin and evolution are still poorly understood. The aim of our study was to analyse the natural history of honeycombing in patients treated with single-lung transplantation. MATERIALS AND METHODS: We considered seven patients who underwent single-lung transplantation; two of them (28.6%) were excluded from our analysis because they died in the posttransplantation period, whereas the remaining five (71.4%) were evaluated with computed tomography (CT) over 67.6±38.56 months. Each CT scan was assessed for disease extension and cyst size (visual score and size of target cysts); CT scans acquired after 2006 were also assessed for native lung volume. RESULTS: All patients showed disease progression (with a concurrent reduction in lung volume in two, 40%) and a progression of honeycombing, with increased number and size of cysts in four (80%). We observed dimensional changes in all target cysts (enlargement or reduction); three patients (60%) also had radiological evidence of complications, such as spontaneous rupture with pneumothorax and development of mycetomas within the cysts. CONCLUSIONS: Honeycombing is a dynamic process in which the overall trend is represented by a dimensional increase in cystic pattern; however, single cysts may have a different evolution (enlargement, reduction or complications). This behaviour could be explained by the variety of the pathogenetic processes underlying honeycombing, with cysts that may present abnormal communication with the airway, including the development of a check-valve mechanism.

E-learning in radiology: an Italian multicentre experience.

OBJECTIVE: The aim of this study was to design, deliver and evaluate an e-learning teaching programme for post-graduate radiodiagnostics training that would involve various post-graduate schools throughout Italy. MATERIALS AND METHODS: All of the Directors of Italian post-graduate schools of radiodiagnostics were sent an e-mail on 27 September 2010 informing them of our willingness to set up an e-learning project for the academic year 2010-2011 in the form of single-subject teaching seminars. The proposed subjects were the semeiotics of the various organs and apparatuses in the context of "Urgent/Emergency Pathology". After having received registrations, a calendar of lessons was planned to be held between 10 November 2010 and 12 October 2011. The validity of the project was tested by means of a multiple-choice questionnaire covering the technical and didactic quality of the entire project, to be completed by the students. RESULTS: Fifty-one percent of the universities in Italy participated in the project: Trieste, Udine, Verona, Milan-Bicocca, Novara, Varese, Genoa, Sassari, Rome Campus, the Catholic University of Rome, Chieti, Foggia, Catania, Modena, Florence, Palermo, Bologna, Pavia, Parma and Ferrara. The lessons were attended by a total of 10,261 post-graduate medical students, for an average of 513.1 students per lesson. Seventy percent of the students judged the didactic content "excellent", 25% "good", and 5% "satisfactory"; none said it was unsatisfactory. In terms of visual quality (particularly the details of the radiological images proposed in the form of slides and/or video clips), 73% judged it "excellent", 20% "good", 6% "satisfactory", and 1% "poor". The audio quality was judged "excellent" by 71%, "good" by 22%, "satisfactory" by 6% and "poor" by 1%. In relation to judgement of audio and video quality, it has to be underlined that this was greatly affected by the hardware/software configuration and the band speed and technology of the Internet connection. CONCLUSIONS: Technological evolution is overcoming all barriers, and technology is also having a positive impact on the approach to teaching. Our multicentre teaching experience merits the following considerations: the quality of the teaching product was certified by the students' judgements of its didactic content and the quality of reception; the economic cost of the teaching had a minimal impact on the post-graduate schools (€ 18 per lesson). In terms of breaking down national barriers, it is to be hoped that the coordination and integration of diagnostic imaging e-learning projects, with the participation of post-graduate schools in different European countries, can be developed not only in a spirit of "cultural sharing" and the exchange of teaching experiences.

Follow-up in pulmonary sarcoidosis: comparison between HRCT and pulmonary function tests.

PURPOSE: The authors assessed the clinical usefulness of high-resolution computed tomography (HRCT) for monitoring sarcoidosis by comparing changes on HRCT with those on pulmonary function test (PFT) results over time. MATERIALS AND METHODS: The baseline and follow-up (after 13 months, range 15-63 months) HRCT scans of 14 consecutive patients with sarcoidosis were reviewed by a single observer. Each follow-up HRCT examination was assessed as stable, improved (when the extent of HRCT findings was reduced compared with baseline) and worsened (when the extent of HRCT findings was increased and/or when HRCT pattern had become fibrotic compared with baseline). Any increase or decrease in forced vital capacity (FVC)≥10% from baseline was considered significant. Changes on HRCT were then compared with those on FVC. RESULTS: During a median follow-up of 33 (range 15-63) months, HRCT findings worsened in 8/14 (58%) cases, improved in 3/14 (21%) and remained stable in 3/14 (21%). Agreement between changes on HRCT and FVC was moderate (κ=0.49). In 9/14 (64%) cases, HRCT changes were in line with those on FVC. In 4/5 discordant cases, the worsened HRCT findings were not mirrored by FVC changes. CONCLUSIONS: Despite the small size of our study population, our results suggest that HRCT may provide clinicians with additional information about the evolution of sarcoidosis.

Densitometric CT evaluation of acute and chronic thromboembolic filling defects of the pulmonary arteries before and after contrast injection.

PURPOSE: The aim of this study was to assess the baseline computed tomography (CT) attenuation of acute and chronic pulmonary thromboemboli, their contrast enhancement (CE), correlation with haematocrit (Ht) levels and the presence of hypertrophic bronchial arteries. MATERIALS AND METHODS: From January 2006 to October 2009, we measured the baseline and postcontrast attenuation values of acute pulmonary thrombi emboli on CT angiograms of 86 patients with acute pulmonary embolism (PE) and those of chronic thrombi in 29 patients with pulmonary hypertension of various origins. The attenuation of acute thrombi was correlated with Ht and CE of chronic thrombi with the presence of hypertrophic bronchial arteries. RESULTS: Acute emboli had a mean baseline attenuation of 54.9 Hounsfield units (HU) and showed no CE. The attenuation of acute thrombi was not dependent on Ht. Chronic thrombi had a mean baseline attenuation of 33.8 HU, and 54% of thrombi showed significant CE. In 57% of cases, a collateral circulation had developed. In 76.5% of cases, CE and hypertrophic bronchial arteries coexisted (p=0.026). Neither thrombotic CE nor bronchial artery hypertrophy predominated in any one of the diseases associated with chronic thrombosis. CONCLUSIONS: Before contrast administration, acute emboli coare prevalently hyperattenuating and therefore more conspicuous. Only chronic thrombi exhibit CE, and CE is significantly associated with the development of collateral circulation, which may be involved in the process of thrombotic recanalisation.

Evaluation of mosaic pattern areas in HRCT with Min-IP reconstructions in patients with pulmonary hypertension: could this evaluation replace lung perfusion scintigraphy?

PURPOSE: The aim of this study is to evaluate a possible correlation between areas of lung attenuation, found in minimum intensity projection (Min-IP) reconstruction images performed with high resolution computed tomography without contrast medium (HRCT), and areas of lung perfusion alteration, found in lung perfusion scintigraphy (LPS). MATERIALS AND METHODS: Two independent radiologists, unaware of LPS results, evaluated retrospectively a group of 113 patients affected by pulmonary hypertension (HP) of different aetiology. These have been examined in a period of two years in our centre both by spiral computed tomography (CT) with and without contrast-medium and by LPS. The final diagnosis was determined on clinical data, right heart catheterisation and contrast enhanced CT in angiographic phase (CTPA). We reconstructed the Min-IP images of lung parenchyma in all the cases both in HRCT without contrast-medium, and in contrast enhanced CT in angiographic phase (CTPA) in axial, sagittal and coronal planes. The obtained images were qualitatively graded into three categories of pulmonary attenuation: homogeneous, inhomogeneous with non-segmental patchy defects, inhomogeneous with segmental defects. The same criteria of classification were used also for LPS images. In the group of patients with chronic thromboembolic pulmonary hypertension (CTEPH) we also compared the number of areas of lung attenuation found in Min-IP images in HRCT without contrast-medium, and their exact localization, with not perfused areas in LPS. Gold standard for the diagnosis of pulmonary embolism was spiral contrast enhanced CT in angiographic phase (CTPA). RESULTS: In all cases we found exact correspondence between the Min-IP images in HRCT with and without contras agent. The attenuation pattern seen on Min-IP images was concordant with those of LPS in 96 out of 113 patients (85%). In the remaining 17 cases (15%) it was discordant: in 12 cases inhomogeneous in Min-IP images (7 with non-segmental patchy defects, 5 with segmental defects) and homogeneous in LPS, in 5 cases inhomogeneous (1 with non-segmental patchy defects, 4 with segmental defects) in LPS images and homogeneous in Min-IP. In a general view, Min-IP reconstruction without contrast-medium showed a sensitivity of 100% and specificity of 96.1%, positive predictive value (PPV) of 92.3% and negative predictive value (NPV) of 100%, to recognize a pattern of lung attenuation inhomogeneous with segmental defects correspondent to a chronic thromboembolic condition, no false negative cases and three false positive cases; on the other hand LPS, on its own, showed a sensitivity of 91.67% and specificity of 93.51%, positive predictive value (PPV) of 86.84% and negative predictive value (NPV) of 96%, 3 false negative cases and 5 false positive cases. CONCLUSION: Min-IP obtained in HRCT without contrast-medium and in CTPA were equivalent. Min-IP images generally showed a higher sensitivity and specificity than LPS in the evaluation of lung perfusion regarding patients with pulmonary hypertension caused by different etiology, particularly in CTEPH patients. These results can be completed with the evaluation of HRCT and CTPA basal scans, providing more informations than ventilation/perfusion lung scintigraphy. HRCT images integrated by Min-IP reconstruction can represent the first step in the diagnostic algorithm of patients affected by dyspnoea and pulmonary hypertension of unknown causes, reserving the use of contrast-medium only in selected patients and reducing the patients' X-ray-exposition.

Post-ARDS pulmonary fibrosis in patients with H1N1 pneumonia: role of follow-up CT.

PURPOSE: Our aim was to evaluate the evolution of 20 patients with H1N1 pneumonia, focusing our attention on patients with severe clinical and radiological findings who developed post-acute respiratory distress syndrome (post-ARDS) pulmonary fibrosis. MATERIALS AND METHODS: Twenty adult patients (nine women and 11 men; mean age 43.5 ± 16.4 years) with a diagnosis of H1N1 infection confirmed by pharyngeal swab came to our attention from September to November 2009 and were followed up until September 2010. All patients were hospitalised in consideration of the severity of clinical findings, and all underwent chest X-ray. Twelve of them underwent at least one computed tomography (CT) scan of the chest. RESULTS: In 75% of cases (15/20), there was complete resolution of the clinical and radiological findings. Twenty-five percent of patients (5/20) developed acute respiratory distress syndrome (ARDS), which progressed to predominantly peripheral pulmonary fibrosis in 10% (2/20; one died and one had late-onset pulmonary fibrosis, documented on day 68). Moreover, in one patient with a CT diagnosis of pulmonary fibrosis, we observed progressive regression of radiological findings over 4 months of follow-up. CONCLUSIONS: In patients with H1N1 pneumonia, post-ARDS pulmonary fibrosis is not a rare complication. Therefore, a CT scan should be performed in all patients with severe clinical findings. Our study demonstrated that in these patients, fibrosis could present a different spatial distribution and a different temporal trend, with delayed late onset; moreover, in one case, the signs of interstitial lung disease partially regressed over time. Therefore, CT should be considered not only in the diagnostic stage, but also during the follow-up.

Subclinical interstitial lung abnormalities in stable renal allograft recipients in the era of modern immunosuppression.

BACKGROUND: Interstitial lung abnormalities have been detected in up to 24% of kidney transplant patients receiving traditional immunosuppressive therapies (eg, cyclosporine, azathioprine); they usually occur early after transplantation and tend to resolve over time. Newer immunosuppressants such as mycophenolic acid and, particularly, mammalian target of rapamycin (mTOR) inhibitors (eg, sirolimus) may cause significant lung toxicity. However, the prevalence and severity of interstitial lung lesions in long-term, stable kidney transplant patients receiving either traditional or newer immunosuppressants is not known. METHODS: We conducted a prospective, cross-sectional study examining high-resolution lung computed tomography (CT) scans in 63 stable kidney transplant recipients whose immunosuppressive therapy had remained unchanged for over 24 months. We compared CT findings of patients taking newer (mycophenolic acid and mTOR inhibitors) and traditional (calcineurin inhibitors and azathioprine) immunosuppressive drugs. RESULTS: Interstitial lung alterations were observed in only 3/63 patients (4.8%); the prevalence was 11.5% (3/26) versus 0% (0/37) among the newer versus traditional immunosuppressive therapy groups, respectively (P = .065). The CT patterns were usual interstitial pneumonia and nonspecific interstitial pneumonia-like. The median time between transplant and CT was 49 months in the three patients with CT alterations and 95 months in the remaining 23 patients on newer immunosuppressants. It was 75 months for all patients on newer immunosuppressive drugs and 133 months for those on traditional therapies (P = .0015). A follow-up CT, performed in 2/3 patients with interstitial abnormalities, showed that the lesions were stable in one, while they had disappeared in the other. CONCLUSIONS: Interstitial lung abnormalities are infrequent and mild in stable kidney transplant patients treated with newer as well as traditional immunosuppressive drugs. As such abnormalities were detected in patients screened earlier after transplantation, the time since transplantation rather than the drug type is probably the major determinant.

Application of a new pulmonary artery obstruction score in the prognostic evaluation of acute pulmonary embolism: comparison with clinical and haemodynamic parameters.

PURPOSE: Evaluation of computed tomography (CT) pulmonary angiography parameters revealing pulmonary embolism (PE) severity with particular attention to pulmonary obstruction indexes. Comparison with clinical and hemodynamic data and determination of predictive role in the development of chronic pulmonary heart disease. MATERIALS AND METHODS: This retrospective study analyzes 45 not consecutive patients from November 2007 to December 2008 with CT angiography diagnosis of acute PE. Included in the study are patients at the first documented episode of acute PE, with 6 month follow-up. Patients with severe pre-existent cardiopulmonary pathology or neoplastic diseases were excluded from the study. CT angiography evaluated right ventricular (RV)/left ventricular (LV) ratio, obstruction index according to Qanadli and Total Clot Burden (Ghanima score). PE indexes were compared with Troponin I measurement and echocardiography result; at last hospitalization and intensive care time were reported. RESULTS: A significant association was found between Ghanima and Qanadli score: the two indexes are equivalent in quantification of pulmonary arterial obstruction (p<0.001). Among others CT parameters, the new Ghanima score evidenced the best accuracy to detect patients evolving to chronic pulmonary heart disease (76%). This value is higher than that of echocardiography (71%). Troponins showed highest accuracy (82%). CONCLUSIONS: Ghanima score can be used in emergency CT angiography diagnosis as prognostic marker for a quickly risk stratification of pulmonary heart disease or death in patients with acute PE. This approach allows to obtain, with just one test, both the diagnosis and a rather accurate acute PE risk stratification.

Benefits of 3D technique in guiding percutaneous retroperitoneal biopsies.

PURPOSE: This study aimed to assess the usefulness and advantages of multiplanar reformations (MPR) during multidetector-row computed tomography (MDCT)-guided percutaneous fine-needle aspiration biopsy (FNAB) and core biopsy of retroperitoneal lesions that are difficult to access with the guidance of ultrasound and axial CT alone owing to overlying bony structures, large vessels or abdominal organs. MATERIALS AND METHODS: MDCT-guided retroperitoneal FNAB and core biopsy was performed on 14 patients with suspected retroperitoneal neoplasm. We used MPR images (sagittal and coronal) obtained with a six-detector-row MDCT scanner and 20-22 gauge Chiba needles. RESULTS: Using MDCT with 3D MPR allowed biological samples to be obtained in all cases (ten cytological and four histological) and diagnostic samples in 11/14 cases (78.5%). Histological samples were deemed adequate for diagnostic assessment in all cases and cytological samples in 7/10 cases (70%). CONCLUSIONS: MPR images allowed sampling of retroperitoneal lesions until now considered unreachable with the guidance of axial MDCT alone. Compared with the conventional procedure, the use of MPR images does not increase the procedure time.

Interstitial lung diseases in a lung cancer screening trial.

We assessed the prevalence of interstitial lung disease (ILD) in a cohort of smokers included in a lung cancer screening trial. Two observers independently reviewed, for the presence of findings consistent with ILD, the computed tomography (CT) examinations of 692 heavy smokers recruited by the Multicentric Italian Lung Detection (MILD) trial. Four CT patterns were considered: usual interstitial pneumonia (UIP), other chronic interstitial pneumonia (OCIP), respiratory bronchiolitis (RB) and indeterminate. Subsequently, the evolution of ILD in those subjects who had undergone a repeat CT examination after 3 yrs was assessed. The UIP pattern and the OCIP pattern were identified in two (0.3%) out of 692 and 26 (3.8%) out of 692 patients, respectively; 109 (15.7%) out of 692 patients showed CT abnormalities consistent with RB, while an indeterminate CT pattern was reported in 21 out of 692 (3%) patients. Age, male sex and current smoking status were factors associated with the presence of OCIP and UIP (combined) pattern, although the relationship did not attain statistical significance. A progression of the disease was observed in three (25%) out of 12 subjects with OCIP who underwent repeat CT after 3 yrs. Thin-section CT features of ILD, probably representing smoking-related ILD, are not uncommon in a lung cancer screening population and should not be overlooked.

Critical issues in radiology requests and reports.

PURPOSE: This study evaluated the appropriateness and accuracy of 500 radiology requests and their matched reports in order to identify recurring errors in both areas. MATERIALS AND METHODS: A randomly chosen sample consisting of 167 computed tomography (CT), 166 ultrasonography (US) and 167 radiographic examinations were collected and analysed according to national referral guidelines and to the principles of justification and optimisation (Law no. 187/2000). RESULTS: We identified a high rate of inappropriate requests (27.6%) and requests lacking a clinical question (22%). There was good precision in the anamnestic data (80.6%) and in the formulation of the diagnostic question (76.8%). Almost all requests were handwritten, and 12.5% lacked the referring physician's stamp and/or signature. No report mentioned the clinical information received or the equipment used. The use of contrast medium was always reported. Conclusions were reported in 9.8% of these reports. When further investigation would have been necessary, the radiologist omitted to report this in 60% of cases. CONCLUSIONS: Some important weaknesses emerged, especially regarding requests for radiological examinations (22% lacked the clinical question, 27.6% were inappropriate), potentially limiting the effectiveness of the diagnostic process and leading to negative effects on the correct risk management process. There emerges a need for better collaboration between clinicians and radiologists.