Human T-cell Lymphotropic Virus Type-1-associated Bronchioloalveolar Disorder with Non-necrotizing Granulomas: A Case Report and Literature Review

Human T-cell lymphotropic virus type-1 (HTLV-1)-associated bronchioloalveolar disorder (HABA) is a pulmonary disorder characterized by lymphocytic infiltration of the peribronchiolar space and interstitium in HTLV-1 carriers and in adult T-cell leukemia/lymphoma (ATLL). We herein report an 85-year-old woman carrying HTLV-1 with HABA who presented with a miliary pattern of micronodules in both lungs on high-resolution computed tomography and a lymphocytic infiltrate with non-necrotizing granulomas on pathology. This rare case of HABA should be differentiated from sarcoidosis, hypersensitivity pneumonitis, or miliary tuberculosis.

Japanese clinical practice guide 2022 for hypersensitivity pneumonitis

Considering recently published two guidelines for the diagnosis of hypersensitivity pneumonitis (HP), the Japanese Respiratory Society (JRS) has now published its own Japanese clinical practice guide for HP. Major types of HP in Japan include summer-type, home-related, bird-related, farmer's lung, painter's lung, humidifier lung, and mushroom grower's lung. Identifying causative antigens is critical for increasing diagnostic confidence, as well as improving prognosis through appropriate antigen avoidance. This guide proposes a comprehensive antigen questionnaire including the outbreak sources reported in Japan. Drawing on the 2021 CHEST guideline, this guide highlights the antigen identification confidence level and adaptations for environmental surveys. The detection of specific antibodies against causative antigens is an important diagnostic predictor of HP. In Japan, the assessments of bird-specific IgG (pigeons, budgerigars) and the Trichosporon asahii antibody are covered by medical insurance. Although this guide adopts the 2020 ATS/JRS/ALAT guideline diagnostic criteria based on the combination of imaging findings, exposure assessment, bronchoalveolar lavage lymphocytosis, and histopathological findings, it added some annotations to facilitate the interpretation of the content and correlate the medical situation in Japan. It recommends checking biomarkers; seasonal changes in the KL-6 concentration (increase in winter for bird-related HP/humidifier lung and in summer for summer-type HP) and high KL-6 concentrations providing a basis for the suspicion of HP. Antigen avoidance is critical for disease management of HP. This guide also addresses the pharmacological management of HP, highlighting the treatment strategy for fibrotic HP including combination therapies with anti-inflammatory/immunosuppressive and antifibrotic drugs.

Stepwise diagnostic algorithm for high-attenuation pulmonary abnormalities on CT

High-attenuation pulmonary abnormalities are commonly seen on CT. These findings are increasingly encountered with the growing number of CT examinations and the wide availability of thin-slice images. The abnormalities include benign lesions, such as infectious granulomatous diseases and metabolic diseases, and malignant tumors, such as lung cancers and metastatic tumors. Due to the wide spectrum of diseases, the proper diagnosis of high-attenuation abnormalities can be challenging. The assessment of these abnormal findings requires scrutiny, and the treatment is imperative. Our proposed stepwise diagnostic algorithm consists of five steps. Step 1: Establish the presence or absence of metallic artifacts. Step 2: Identify associated nodular or mass-like soft tissue components. Step 3: Establish the presence of solitary or multiple lesions if identified in Step 2. Step 4: Ascertain the predominant distribution in the upper or lower lungs if not identified in Step 2. Step 5: Identify the morphological pattern, such as linear, consolidation, nodular, or micronodular if not identified in Step 4. These five steps to diagnosing high-attenuation abnormalities subdivide the lesions into nine categories. This stepwise radiologic diagnostic approach could help to narrow the differential diagnosis for various pulmonary high-attenuation abnormalities and to achieve a precise diagnosis.Critical relevance statement Our proposed stepwise diagnostic algorithm for high-attenuation pulmonary abnormalities may help to recognize a variety of those high-attenuation findings, to determine whether the associated diseases require further investigation, and to guide appropriate patient management. Key points • To provide a stepwise diagnostic approach to high-attenuation pulmonary abnormalities.• To familiarize radiologists with the varying cause of high-attenuation pulmonary abnormalities.• To recognize which high-attenuation abnormalities require scrutiny and prompt treatment.

MRI Findings and Differential Diagnosis of Anterior Mediastinal Solid Tumors

The anterior mediastinum is the most common location of mediastinal tumors, and thymic epithelial tumors are the most common mediastinal tumors. It is important to differentiate thymic epithelial tumors from malignant lymphomas and malignant germ cell tumors because of the different treatment strategies. Dynamic contrast-enhanced MRI and diffusion-weighted imaging can provide additional information on the differential diagnosis. Chemical shift imaging can detect tiny fat tissues in the lesion and is useful in differentiating thymic hyperplasia from other solid tumors such as thymomas. MRI findings reflect histopathological features of mediastinal tumors, and a comprehensive evaluation of MRI sequences is important for estimation of the histopathological features of the tumor. In this manuscript, we describe the MRI findings of anterior mediastinal solid tumors and the role of MRI in the differential diagnosis.

Time to enhancement of breast lesions and normal breast parenchyma in light of menopausal status and menstrual cycle for ultrafast dynamic contrast-enhanced MRI using compressed sensing

PURPOSE

To assess the dependency of the Time to enhancement (TTE) of breast lesions and normal breast parenchyma from menopausal status and menstrual cycle using ultrafast compressed sensing (CS) -accelerated dynamic contrast-enhanced (DCE) MRI.

METHODS

This institutional review board approved retrospective study included 89 breast cancers, 22 benign lesions and 131 normal breast parenchymal foci. A prototypical ultrafast DCE sequence obtained 30 phases with 2.9 s temporal resolution. Mean and median TTE of all breast cancers, benign lesions and normal breast parenchymal foci were assessed. we also assessed whether there were any differences in TTE regarding the menopausal status and menstrual cycle.

RESULTS

The TTE of breast cancer was significantly shorter than that of benign lesions and normal breast parenchymal foci in both the premenopausal status (5.8 vs. 8.7 and 8.7 s, respectively) (p = 0.0028 and < 0.0001, respectively) and postmenopausal status (5.8 vs. 11.6 and 11.6 s, respectively) (p < 0.0001 in both). The TTE of parenchymal foci in the premenopausal status was significantly shorter than that in the postmenopausal status (p = 0.0025). Although the TTE interval between cancer and parenchymal foci in premenopausal status is shorter than that in postmenopausal status, the AUCs in the pre- and postmenopausal status for differentiating breast cancer and parenchymal foci were comparable with using different cutoff TTE values. There were no differences in TTE regarding the menstrual cycle.

CONCLUSIONS

The TTE derived from ultrafast CS-accelerated DCE MRI was useful to differentiate breast cancer from benign lesions and normal breast parenchymal foci in both pre- and postmenopausal status.

Nationwide retrospective observational study of idiopathic dendriform pulmonary ossification: clinical features with a progressive phenotype

BACKGROUND

Diffuse pulmonary ossification is a specific lung condition that is accompanied by underlying diseases. However, idiopathic dendriform pulmonary ossification (IDPO) is extremely rare, and the clinical features remain unclear. In this study, we aimed to report the clinical characteristics of IDPO.

METHODS

We conducted a nationwide survey of patients with IDPO from 2017 to 2019 in Japan and evaluated the clinical, radiological, and histopathological findings of patients diagnosed with IDPO.

RESULTS

Twenty-two cases of IDPO were identified. Most subjects (82%) were male, aged 22-56 years (mean (SD), 37.9 (9.1)) at diagnosis. Nearly 80% of the subjects were asymptomatic, and the condition was discovered during a medical check-up. However, 36% of the subjects showed a decline in forced vital capacity (%FVC) predicted <80% at diagnosis. The typical radiological features of high-resolution CT (HRCT) are calcified branching structures that are predominantly distributed in the lower lung fields without any other conspicuous finding. Histopathological analysis also showed dendriform ossified lesions from the intraluminal areas to interstitial areas. Notably, during the follow-up period of 20 years, disease progression was found in 88% on HRCT and more than 50% on pulmonary function tests (FVC and/or forced expiratory volume in 1 s). Two cases with rapid decline of 10% /year in %FVC predicted were observed.)) at diagnosis. Nearly 80% of the subjects were asymptomatic, and the condition was discovered during a medical check-up. However, 36% of the subjects showed a decline in forced vital capacity (%FVC) predicted <80% at diagnosis. The typical radiological features of high-resolution CT (HRCT) are calcified branching structures that are predominantly distributed in the lower lung fields without any other conspicuous finding. Histopathological analysis also showed dendriform ossified lesions from the intraluminal areas to interstitial areas. Notably, during the follow-up period of 20 years, disease progression was found in 88% on HRCT and more than 50% on pulmonary function tests (FVC and/or forced expiratory volume in 1 s). Two cases with rapid decline of 10% /year in %FVC predicted were observed.

CONCLUSIONS

IDPO develops at a young age with gradually progressive phenotype. Further research and long-term (>20 years) follow-up are required to clarify the pathogenesis and clinical findings in IDPO.

Radiological pleuroparenchymal fibroelastosis-like lesion in idiopathic interstitial pneumonias

Background

Pleuroparenchymal fibroelastosis (PPFE) is characterised by predominant upper lobe pleural and subpleural lung parenchymal fibrosis. Radiological PPFE-like lesion has been associated with various types of interstitial lung diseases. However, the prevalence and clinical significance of radiological PPFE-like lesion in patients with idiopathic interstitial pneumonias (IIPs) are not fully understood. We aimed to determine the prevalence and clinical impact on survival of radiological PPFE-like lesion in patients with IIPs.

Methods

A post-hoc analysis was conducted using data from the Japanese nationwide cloud-based database of patients with IIPs. All the patients in the database were diagnosed as having IIPs by multidisciplinary discussion. Patients diagnosed with idiopathic PPFE were excluded. Clinical data and chest computed tomography (CT) image of 419 patients with IIPs were analysed. The presence of radiological PPFE-like lesion was independently evaluated by two chest radiologists blind to the clinical data.

Results

Of the 419 patients with IIPs, radiological PPFE-like lesions were detected in 101 (24.1%) patients, mainly in idiopathic pulmonary fibrosis (IPF) and unclassifiable IIPs, but less in idiopathic nonspecific interstitial pneumonia. Prognostic analyses revealed that radiological PPFE-like lesion was significantly associated with poor outcome in patients with IIPs, which was independent of age, IPF diagnosis and %FVC. In survival analyses, the patients with radiological PPFE-like lesions had poor survival compared with those without (log-rank, p < 0.0001). Subgroup analyses demonstrated that radiological PPFE-like lesion was significantly associated with poor survival both in patients with IPF and those with unclassifiable IIPs.

Conclusion

Radiological PPFE-like lesion is a condition that could exist in IIPs, mainly in IPF and unclassifiable IIPs. Importantly, the radiological PPFE-like lesion is a non-invasive marker to predict poor outcome in patients with IIPs, which should be carefully considered in clinical practice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-021-01892-9.

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

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

Exposure to PM2.5 is a risk factor for acute exacerbation of surgically diagnosed idiopathic pulmonary fibrosis: a case-control study

Background

Short-term exposure to ozone and nitrogen dioxide is a risk factor for acute exacerbation (AE) of idiopathic pulmonary fibrosis (AE-IPF). The comprehensive roles of exposure to fine particulate matter in AE-IPF remain unclear. We aim to investigate the association of short-term exposure to fine particulate matter with the incidence of AE-IPF and to determine the exposure-risk time window during 3 months before the diagnosis of AE-IPF.

Methods

IPF patients were retrospectively identified from the nationwide registry in Japan. We conducted a case–control study to assess the correlation between AE-IPF incidence and short-term exposure to eight air pollutants, including particulate matter < 2.5 µm (PM_2.5). In the time-series data, we compared monthly mean exposure concentrations between months with AE (case months) and those without AE (control months). We used multilevel mixed-effects logistic regression models to consider individual and institutional-level variables, and also adjusted these models for several covariates, including temperature and humidity. An additional analysis with different monthly lag periods was conducted to determine the risk-exposure time window for 3 months before the diagnosis of AE-IPF.

Results

Overall, 152 patients with surgically diagnosed IPF were analyzed. AE-IPF was significantly associated with an increased mean exposure level of nitric oxide (NO) and PM_2.5 30 days prior to AE diagnosis. Adjusted odds ratio (OR) with a 10 unit increase in NO was 1.46 [95% confidence interval (CI) 1.11–1.93], and PM_2.5 was 2.56 (95% CI 1.27–5.15). Additional analysis revealed that AE-IPF was associated with exposure to NO during the lag periods lag 1, lag 2, lag 1–2, and lag 1–3, and PM_2.5 during the lag periods lag 1 and lag 1–2.

Conclusions

Our results show that PM_2.5 is a risk factor for AE-IPF, and the risk-exposure time window related to AE-IPF may lie within 1–2 months before the AE diagnosis. Further investigation is needed on the novel findings regarding the exposure to NO and AE-IPF.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-021-01671-6.

Relationship between MRI findings and invasive breast cancer with podoplanin-positive cancer-associated fibroblasts

OBJECTIVE

Purpose of our study is to assess the relationship between MRI findings and invasive breast cancer (IBC) with cancer-associated fibroblasts (CAFs) that are positive for podoplanin.

METHODS

We retrospectively analyzed the consecutive 109 IBCs. The IBCs were dichotomized as with (+) or without (-) podoplanin-positive CAFs. In MRI analyses, the dichotomized IBCs were compared the lesion to muscle ratio (L/M ratio) in STIR images, the ADC value, the distribution of kinetic parameters, and morphological findings.

RESULTS

Of the 109 IBCs, 28 (26%) IBCs had podoplanin(+) CAFs. Compared to the podoplanin(-) group, the podoplanin(+) group tended to have a more malignant pathological status. In the STIR images, the podoplanin(+) group had significantly higher L/M ratio (7.59 vs. 6.55, p = 0.040). In a dynamic study, the podoplanin(+) group had a significantly higher percentage of the washout pattern (42.21% vs. 29.43%, p = 0.045). There were 23 mass lesions and 5 non-mass enhancement (NME) lesions in the podoplanin(+) group, and 69 mass lesions and 12 NME lesions in the podoplanin(-) group. The mass lesions of the podoplanin(-) group had a significantly higher likelihood of showing an irregular shape (n = 47 vs. 8, p = 0.035). The podoplanin(+) group's lesions had a significantly higher likelihood of showing a circumscribed margin (n = 14 vs. 6, p < 0.001) and a rim enhancement (n = 10 vs. 13, p = 0.047). In multivariate analyses, only high nuclear grade was significant predictive value of podoplanin(+) CAFs.

CONCLUSION

Although not significant in multivariate analyses, MRI findings may be used to determine the podoplanin-positive CAF status of invasive breast cancer.

Pleuroparenchymal fibroelastosis-like lesions in patients with interstitial pneumonia diagnosed by multidisciplinary discussion with surgical lung biopsy

Purpose

The present study aimed to evaluate the significance of Pleuroparenchymal fibroelastosis (PPFE)-like lesions in predicting prognosis in patients with chronic interstitial pneumonia (IP).

Method

The present study enrolled 207 patients with IP in whom surgical lung biopsy was performed. Among the patients enrolled in the present study, 77 had idiopathic pulmonary fibrosis (IPF), 15 had nonspecific interstitial pneumonia (NSIP), 13 had chronic hypersensitivity pneumonitis (CHP), 41 had connective tissue disease (CTD), three had PPFE, and 58 had unclassifiable diagnosis. The incidence, characteristics, and thickness of PPFE-like lesions were evaluated in each patient with IP. Additionally, the influence of PPFE-like lesions on the prognosis was also determined.

Results

Of 207 patients, 160 (77.3 %) showed PPFE-like lesions. The frequency of PPFE-like lesions was similar in patients with IPF, NSIP, CHP, CTD, and unclassifiable diagnosis (79.5 %, 79.5 %, 73.2 %, 65.9 %, and 81 %, respectively); however, PPFE-like lesions were present in all patients with PPFE (p = 0.42). Consequently, there was no significant difference in the characteristics of PPFE-like lesions among patients with all forms of IP, except PPFE. PPFE-like lesions were not a significant predictor of prognosis (hazard ratio [HR], 1.16; 95 % confidence interval [CI], 0.64–2.10, p = 0.62); however, patients with PPFE-like lesions under the aortic arch had significantly poorer prognoses (HR, 2.70; 95 % CI, 1.66–4.39, p < 0.001). For craniocaudal extent comparison, patients with IPF with PPFE-like lesions below the level of the carina had significantly poorer prognoses than those without PPFE-like lesions (p = 0.001, overall survival 53.1 and 80.6, respectively).

Conclusion

PPFE-like lesions are common in patients with IP, and their characteristics were not significantly different among all forms of IP, except idiopathic PPFE. The broad extent of PPFE-like lesions is an important predictor of prognosis in patients with IPF.

Pleuroparenchymal fibroelastosis (PPFE)-like finding on CT in daily practice -prevalence and serial changes

Objective

To characterize the prevalence of PPFE (pleuroparenchymal fibroelastosis)-like finding on CT in daily practice and to identify the risk factors for its progression.

Matelials & methods

2416 consecutive daily CT examinations were screened for PPFE-like finding. CT images with PPFE-like finding were retrospectively reviewed for the extent, maximum height, presence or absence of intraalveolar fibroelastosis (IAFE), emphysema, interstitial lung disease (ILD), suprasternal depression at the level of clavicle end, and bronchiectasis in upper lobe, and anterior-posterior/transverse diameter ratio (AT ratio) of thoracic cage. Serial CT scans more than 3 years before the baseline scan were also reviewed and compared when available.

Results

380 patients (median age of 65, M:F = 153:227) were recognized as having PPFE-like finding. The lowest level of PPFE-like finding was T5 in median, horizontal extent was 0–25 % in 229/380, 25–50 % in 66 and >50 % in 24. Median height was 8.0 mm. IAFE was seen in 75, emphysema in 71, ILD in 59, chronic bronchial disorder in 71, suprasternal depression in 148, upper-lobe bronchial dilatation in 124. Mean AT ratio was 0.63. Serial images were available in 131 patients. 11 showed significant progression, 57 showed mild progression. Existing ILD lesion and >25 % horizontal extent were significantly related to significant progression.

Conclusions

PPFE-like finding was seen relatively in high proportion. Extensive lesion in axial plane and co-existing ILD might be risk factors of progression.

Influenza H1N1 virus-associated pneumonia often resembles rapidly progressive interstitial lung disease seen in collagen vascular diseases and COVID-19 pneumonia; CT-pathologic correlation in 24 patients

Purpose

To describe computed tomography (CT) findings of influenza H1N1 virus-associated pneumonia (IH1N1VAP), and to correlate CT findings to pathological ones.

Methods

The study included 24 patients with IH1N1VAP. Two observers independently evaluated the presence, distribution, and extent of CT findings. CT features were divided into either classical form (C-form) or non-classical form (NC-form). C-form included: A.) broncho-bronchiolitis and bronchopneumonia type, whereas NC-forms included: B.) diffuse peribronchovascular type, simulating subacute rheumatoid arthritis-associated (RA) interstitial lung disease (ILD) and C.) lower peripheral and/or peribronchovascular type, resembling dermatomyositis-associated ILD and COVID-19 pneumonia. In 10 cases with IH1N1VAP where lung biopsy was performed, CT and pathology findings were correlated.

Results

The most common CT findings were ground-glass opacities (24/24, 100 %) and airspace consolidation (23/24, 96 %). C-form was found in 11 (46 %) patients while NC-form in 13 (54 %). Types A, B, and C were seen in 11(46 %), 4 (17 %), and 9 (38 %) patients, respectively. The lung biopsy revealed organizing pneumonia in all patients and 6 patients (60 %) showed incorporated type organizing pneumonia that was common histological findings of rapidly progressive ILD.

Conclusion

In almost half of patients of IH1N1VAP, CT images show NC-form pneumonia pattern resembling either acute or subacute RA or dermatomyositis-associated ILD and COVID-19 pneumonia.

Maximum slope of ultrafast dynamic contrast-enhanced MRI of the breast: Comparisons with prognostic factors of breast cancer

PURPOSE

To determine the relationship between the maximum slope (MS) of ultrafast dynamic contrast-enhanced (DCE)-MRI and prognostic factors of breast cancer.

METHODS

One hundred thirteen patients with 118 breast cancers were included in this study. The ultrafast DCE sequence was acquired using a higher parallel imaging factor. Its spatial resolution was 0.9 × 0.9 × 2.5 mm and its temporal resolution was 8.3 s/phase. Each lesion was automatically segmented, and the ROI of highest enhancement in the lesion was identified. In this ROI, the MS was calculated. The MS of each lesion was compared with various prognostic factors of breast cancer.

RESULTS

The MS of invasive cancer (median: 9.81%/sec) was significantly higher than that of ductal carcinoma in situ (median: 7.26%/sec) (p = 0.001). In the ROC analysis, the area under the ROC curve (AUC) was 0.7295. The MS of invasive cancer with axillary lymph node (LN) metastasis (median: 11.97%/sec) was significantly higher than that without axillary LN metastasis (median: 9.425%/sec) (p = 0.0024). In the ROC analysis, the AUC was 0.7177. In addition, the MS became significantly higher as the level of the proliferation marker ki-67 increased (correlation coefficient: 0.3317) (p = 0.0009).

CONCLUSIONS

MS of ultrafast DCE-MRI is useful for predicting the prognostic factors of breast cancer. Higher maximum slope (MS) is significantly associated with an invasive breast cancer component. Higher MS is significantly associated with an axillary lymph node metastasis. MS becomes significantly higher with increasing ki-67 (a proliferation marker). Ultrafast MRI is useful for predicting the prognostic factors of breast cancer.

Anterior mediastinal lesions: CT and MRI features and differential diagnosis

Anterior mediastinum is the most common location of mediastinal tumors, which include various solid and cystic lesions. The lesion location and CT and MRI features are important in the differential diagnosis. Recently, CT-based mediastinal compartment classification systems were proposed and suggested to be useful for accurate evaluation of mediastinal lesions. CT and MRI reflect the pathological findings of mediastinal lesions, and knowledge of the pathological features is important for the differential diagnosis. In this article, we review the CT and MRI features of anterior mediastinal lesions and describe important points in the differential diagnosis.

Diagnosis of Hypersensitivity Pneumonitis in Adults. An Official ATS/JRS/ALAT Clinical Practice Guideline

Background: This guideline addresses the diagnosis of hypersensitivity pneumonitis (HP). It represents a collaborative effort among the American Thoracic Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax.Methods: Systematic reviews were performed for six questions. The evidence was discussed, and then recommendations were formulated by a multidisciplinary committee of experts in the field of interstitial lung disease and HP using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach.Results: The guideline committee defined HP, and clinical, radiographic, and pathological features were described. HP was classified into nonfibrotic and fibrotic phenotypes. There was limited evidence that was directly applicable to all questions. The need for a thorough history and a validated questionnaire to identify potential exposures was agreed on. Serum IgG testing against potential antigens associated with HP was suggested to identify potential exposures. For patients with nonfibrotic HP, a recommendation was made in favor of obtaining bronchoalveolar lavage (BAL) fluid for lymphocyte cellular analysis, and suggestions for transbronchial lung biopsy and surgical lung biopsy were also made. For patients with fibrotic HP, suggestions were made in favor of obtaining BAL for lymphocyte cellular analysis, transbronchial lung cryobiopsy, and surgical lung biopsy. Diagnostic criteria were established, and a diagnostic algorithm was created by expert consensus. Knowledge gaps were identified as future research directions.Conclusions: The guideline committee developed a systematic approach to the diagnosis of HP. The approach should be reevaluated as new evidence accumulates.

Pleuroparenchymal fibroelastosis in systemic sclerosis: prevalence and prognostic impact

Interstitial lung disease (ILD) in systemic sclerosis (SSc) is a major cause of morbidity and mortality, mostly presenting as non-specific interstitial pneumonia. Little is known about the prevalence of pleuroparenchymal fibroelastosis (PPFE), a specific entity affecting the visceral pleura and subpleural parenchyma. We set out to estimate PPFE prevalence in two large cohorts of SSc patients and to assess its impact on survival and functional decline.A total of 359 SSc patients, derived from two referral centres in two different countries (UK and Italy), were included. The first available high-resolution computed tomography scan was independently evaluated by two radiologists blind to clinical information, to quantify ILD extent, freestanding bronchial abnormalities, and lobar percentage involvement of PPFE on a four-point categorical scale. Discordant scores were adjudicated by a third scorer. PPFE extent was further classified as limited (≤2/18) or extensive (>2/18). Results were evaluated against functional decline and mortality.The overall prevalence of PPFE in the combined SSc population was 18% (11% with extensive PPFE), with no substantial difference between the two cohorts. PPFE was significantly linked to free-standing bronchial abnormalities (61% versus 25% in PPFE versus no PPFE; p<0.0001) and to worse survival, independently of ILD severity or short-term lung function changes (HR 1.89, 95% CI 1.10-3.25; p=0.005).In the current study, we provide an exhaustive description of PPFE prevalence and clinical impact in the largest cohort of SSc subjects published so far. PPFE presence should be carefully considered, due to its significant prognostic implications.

Nationwide cloud-based integrated database of idiopathic interstitial pneumonias for multidisciplinary discussion

Multidisciplinary discussion (MDD) requiring close communication between specialists (clinicians, radiologists and pathologists) is the gold standard for the diagnosis of idiopathic interstitial pneumonias (IIPs). However, MDD by specialists is not always feasible because they are often separated by time and location. An online database would facilitate data sharing and MDD. Our aims were to develop a nationwide cloud-based integrated database containing clinical, radiological and pathological data of patients with IIPs along with a web-based MDD system, and to validate the diagnostic utility of web-based MDD in IIPs.

Clinical data, high-resolution computed tomography images and lung biopsy slides from patients with IIPs were digitised and uploaded to separate servers to develop a cloud-based integrated database. Web-based MDD was performed using the database and video-conferencing to reach a diagnosis.

Clinical, radiological and pathological data of 524 patients in 39 institutions were collected, uploaded and incorporated into the cloud-based integrated database. Subsequently, web-based MDDs with a pulmonologist, radiologist and pathologist using the database and video-conferencing were successfully performed for the 465 cases with adequate data. Overall, the web-based MDD changed the institutional diagnosis in 219 cases (47%). Notably, the MDD diagnosis yielded better prognostic separation among the IIPs than did the institutional diagnosis.

This is the first study of developing a nationwide cloud-based integrated database containing clinical, radiological and pathological data for web-based MDD in patients with IIPs. The database and the web-based MDD system that we built made MDD more feasible in practice, potentially increasing accurate diagnosis of IIPs.

Acloud-based integrated database of idiopathic interstitial pneumonias containing clinical, radiological and pathological data along with a web-based multidisciplinary discussion system can make discussions more feasible and improve disease managementhttp://ow.ly/NqqD30nYenb

Analysis of systemic lupus erythematosus-related interstitial pneumonia: a retrospective multicentre study

Thoracic diseases in patients with systemic lupus erythematosus (SLE), especially interstitial pneumonia (SLE-IP), are rare and have been poorly studied. The aims of this multicentre study were to evaluate SLE-IP and elucidate its clinical characteristics and prognosis. Fifty-five patients with SLE-IP who had attended the respiratory departments of participating hospitals were retrospectively evaluated in this multicentre study. Clinical information, high-resolution computed tomography (HRCT), and surgical lung biopsy/autopsy specimens were analysed by respiratory physicians, pulmonary radiologists, and pulmonary pathologists. IP patterns on HRCT and lung specimens were classified based on the international classification statement/guideline for idiopathic interstitial pneumonias. The most frequent form of SLE-IP at diagnosis was chronic IP (63.6%), followed by subacute (20.0%), and acute IP (12.7%). Radiologically, the most common HRCT pattern was “Unclassifiable” (54%). Histologically, “Unclassifiable” was the most frequently found (41.7%) among 12 patients with histologically proven IP. Interestingly, accompanying airway diseases were present in nine of these patients (75%). In multivariate analysis, current smoking (hazard ratio [HR] 6.105, p = 0.027), thrombocytopenia (HR 7.676, p = 0.010), anti-double-strand DNA titre (HR 0.956, p = 0.027), and nonspecific interstitial pneumonia (NSIP) + organizing pneumonia (OP) pattern on HRCT (vs. NSIP, HR 0.089, p = 0.023) were significant prognostic factors. In conclusion, chronic IP was the most frequent form of IP in patients with SLE-IP, and “Unclassifiable” was the commonest pattern radiologically and histologically.

Tumor-stromal ratio (TSR) of invasive breast cancer: correlation with multi-parametric breast MRI findings

OBJECTIVE

To correlate the tumor-stromal ratio (TSR) of invasive breast cancer and MRI findings.

METHODS

This study was approved by our institutional review board. 126 consecutive patients with surgically proven invasive breast cancer were included. All patients underwent MRI exams including short-tau inversion-recovery (STIR) T ₂ weighted imaging, diffusion-weighted imaging (DWI) and post-contrast dynamic imaging. The mean signal intensity (SI) and apparent diffusion coefficient (ADC) value of each lesion were measured. To objectively evaluate the STIR images, the ratio of the SI of the lesion to the muscle (L/M ratio) was also measured. Percentages of MRI kinetic parameters obtained from dynamic images were also measured. The TSR was defined as the percentage of the stromal component, and categorized into high-stroma (> 50%) and low-stroma (< 50%) groups. Intergroup differences in the SI, L/M ratio, ADC value and percentages of kinetic parameters were examined.

RESULTS

The SI and L/M ratio of the high-stroma group were significantly lower than those of the low-stromal group (208.64 vs 331.86 for SI, 5.69 vs 9.31 for L/M ratio) (p < 0.001). The high-stroma group had significantly lower percentages of a washout pattern (25% vs 34.7 %) (p = 0.012) and significantly higher percentages of a persistent pattern (36.92% vs 28.26 %) (p = 0.044). There were no significant correlations between the TSR and ADC value.

CONCLUSION

STIR and dynamic sequence of breast MRI reflects the stromal component of invasive breast cancer.

ADVANCES IN KNOWLEDGE

This is the first study to correlate TSR and MRI findings. STIR and post-contrast dynamic study correlated with the stromal component of breast cancer.

Predicting outcomes in rheumatoid arthritis related interstitial lung disease

The aim of this study was to compare radiology-based prediction models in rheumatoid arthritis-related interstitial lung disease (RAILD) to identify patients with a progressive fibrosis phenotype.

RAILD patients had computed tomography (CT) scans scored visually and using CALIPER and forced vital capacity (FVC) measurements. Outcomes were evaluated using three techniques, as follows. 1) Scleroderma system evaluating visual interstitial lung disease extent and FVC values; 2) Fleischner Society idiopathic pulmonary fibrosis (IPF) diagnostic guidelines applied to RAILD; and 3) CALIPER scores of vessel-related structures (VRS). Outcomes were compared to IPF patients.

On univariable Cox analysis, all three staging systems strongly predicted outcome (scleroderma system hazard ratio (HR) 3.78, p=9×10⁻⁵; Fleischner system HR 1.98, p=2×10⁻³; and 4.4% VRS threshold HR 3.10, p=4×10⁻⁴). When the scleroderma and Fleischner systems were combined, termed the progressive fibrotic system (C-statistic 0.71), they identified a patient subset (n=36) with a progressive fibrotic phenotype and similar 4-year survival to IPF. On multivariable analysis, with adjustment for patient age, sex and smoking status, when analysed alongside the progressive fibrotic system, the VRS threshold of 4.4% independently predicted outcome (model C-statistic 0.77).

The combination of two visual CT-based staging systems identified 23% of an RAILD cohort with an IPF-like progressive fibrotic phenotype. The addition of a computer-derived VRS threshold further improved outcome prediction and model fit, beyond that encompassed by RAILD measures of disease severity and extent.

Combining the scleroderma and Fleischner staging systems in RAILD identifies patients with an IPF-like progressive fibrotic phenotype. CALIPER VRS scores further improve model fit, beyond that encompassed by RAILD measures of disease severity and extent.http://ow.ly/SUcV30mmeYI

Primary Pulmonary Colloid Adenocarcinoma: How Can We Obtain a Precise Diagnosis?

A 76-year-old asymptomatic man was found to have a mass in the right lower lung field. Although the presence of a mucinous component in the majority of the tumor was shown by magnetic resonance imaging, the presence of cancer cells was suspected by contrast enhancement on computed tomography (CT) and based on the partial accumulation in the marginal regions of the tumor on fluorodeoxyglucose-positron emission tomography (FDG-PET). A transbronchial lung biopsy was non-diagnostic, but resection of the mass resulted in a diagnosis of colloid adenocarcinoma. The findings from combined contrast CT and FDG-PET may raise the suspicion of colloid adenocarcinoma and prompt the consideration of surgical resection.

Predicting Outcomes in Idiopathic Pulmonary Fibrosis Using Automated Computed Tomographic Analysis

RATIONALE

Quantitative computed tomographic (CT) measures of baseline disease severity might identify patients with idiopathic pulmonary fibrosis (IPF) with an increased mortality risk. We evaluated whether quantitative CT variables could act as a cohort enrichment tool in future IPF drug trials.

OBJECTIVES

To determine whether computer-derived CT measures, specifically measures of pulmonary vessel-related structures (VRSs), can better predict functional decline and survival in IPF and reduce requisite sample sizes in drug trial populations.

METHODS

Patients with IPF undergoing volumetric noncontrast CT imaging at the Royal Brompton Hospital, London, and St. Antonius Hospital, Utrecht, were examined to identify pulmonary function measures (including FVC) and visual and computer-derived (CALIPER [Computer-Aided Lung Informatics for Pathology Evaluation and Rating] software) CT features predictive of mortality and FVC decline. The discovery cohort comprised 247 consecutive patients, with validation of results conducted in a separate cohort of 284 patients, all fulfilling drug trial entry criteria.

MEASUREMENTS AND MAIN RESULTS

In the discovery and validation cohorts, CALIPER-derived features, particularly VRS scores, were among the strongest predictors of survival and FVC decline. CALIPER results were accentuated in patients with less extensive disease, outperforming pulmonary function measures. When used as a cohort enrichment tool, a CALIPER VRS score greater than 4.4% of the lung was able to reduce the requisite sample size of an IPF drug trial by 26%.

CONCLUSIONS

Our study has validated a new quantitative CT measure in patients with IPF fulfilling drug trial entry criteria-the VRS score-that outperformed current gold standard measures of outcome. When used for cohort enrichment in an IPF drug trial setting, VRS threshold scores can reduce a required IPF drug trial population size by 25%, thereby limiting prohibitive trial costs. Importantly, VRS scores identify patients in whom antifibrotic medication prolongs life and reduces FVC decline.

Evaluation of visual and computer-based CT analysis for the identification of functional patterns of obstruction and restriction in hypersensitivity pneumonitis

BACKGROUND AND OBJECTIVE

To determine whether computer-based quantification (CALIPER software) is superior to visual computed tomography (CT) scoring in the identification of CT patterns indicative of restrictive and obstructive functional indices in hypersensitivity pneumonitis (HP).

METHODS

A total of 135 consecutive HP patients had CT parenchymal patterns evaluated quantitatively by both visual scoring and CALIPER. Results were evaluated against: forced vital capacity (FVC), total lung capacity (TLC), diffusing capacity for carbon monoxide (DL_CO ) and a composite physiological index (CPI) to identify which CT scoring method better correlated with functional indices.

RESULTS

CALIPER-derived scores of total interstitial lung disease extent correlated more strongly than visual scores: FVC (CALIPER R = 0.73, visual R = 0.51); DL_CO (CALIPER R = 0.61, visual R = 0.48); and CPI (CALIPER R = 0·70, visual R = 0·55). The CT variable that correlated most strongly with restrictive functional indices was CALIPER pulmonary vessel volume (PVV): FVC R = 0.75, DL_CO R = 0.68 and CPI R = 0.76. Ground-glass opacity quantified by CALIPER alone demonstrated strong associations with restrictive functional indices: CALIPER FVC R = 0.65; DL_CO R = 0.59; CPI R = 0.64; and visual = not significant. Decreased attenuation lung quantified by CALIPER was a better morphological measure of obstructive lung disease than equivalent visual scores as judged by relationships with TLC (CALIPER R = 0.63 and visual R = 0.12). All results were maintained on multivariate analysis.

CONCLUSION

CALIPER improved on visual scoring in HP as judged by restrictive and obstructive functional correlations. Decreased attenuation regions of the lung quantified by CALIPER demonstrated better linkages to obstructive lung physiology than visually quantified CT scores. A novel CALIPER variable, the PVV, demonstrated the strongest linkages with restrictive functional indices and could represent a new automated index of disease severity in HP.

Chronic hypersensitivity pneumonitis: identification of key prognostic determinants using automated CT analysis

Background

Chronic hypersensitivity pneumonitis (CHP) has a variable disease course. Computer analysis of CT features was used to identify a subset of CHP patients with an outcome similar to patients with idiopathic pulmonary fibrosis (IPF).

Methods

Consecutive patients with a multi-disciplinary team diagnosis of CHP (n = 116) had pulmonary function tests (FEV1, FVC, DLco, Kco, and a composite physiologic index [CPI]) and CT variables predictive of mortality evaluated by analysing visual and computer-based (CALIPER) parenchymal features: total interstitial lung disease (ILD) extent, honeycombing, reticular pattern, ground glass opacities, pulmonary vessel volume (PVV), emphysema, and traction bronchiectasis. Mean survival was compared between both CHP and IPF patients (n = 185).

Results

In CHP, visual/CALIPER measures of reticular pattern, honeycombing, visual traction bronchiectasis, and CALIPER ILD extent were predictive of mortality (p < 0 · 05) on univariate analysis. PVV was strongly predictive of mortality on univariate (p < 0 · 0001) and multivariate analysis independent of age, gender and disease severity (represented by the CPI [p < 0 · 01]). CHP patients with a PVV threshold >6 · 5% of the lung had a mean survival (35 · 3 ± 6 · 1 months; n = 20/116 [17%]) and rate of disease progression that closely matched IPF patients (38 · 4 ± 2 · 2 months; n = 185).

Conclusions

Pulmonary vessel volume can identify CHP patients at risk of aggressive disease and a poor IPF-like prognosis.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-017-0418-2) contains supplementary material, which is available to authorized users.

Diagnostic Performance of Diffusion Tensor Imaging with Readout-segmented Echo-planar Imaging for Invasive Breast Cancer: Correlation of ADC and FA with Pathological Prognostic Markers

Purpose:

To assess the diagnostic performance of readout-segmented echo-planar diffusion tensor imaging (DTI based on rs-EPI) for breast cancer and to determine the correlation between the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values obtained from DTI based on rs-EPI with prognostic markers of invasive breast cancer.

Materials and Methods:

This retrospective study examined 80 pathologically proven breast lesions (22 benign and 58 malignant lesions) of 80 patients who underwent both diffusion-weighted imaging based on single-shot echo-planar imaging (DWI based on ss-EPI) and DTI based on rs-EPI with b-values of 0 and 1000. We identified and compared the diagnostic performances of the DWI based on ss-EPI and the DTI based on rs-EPI using ADCs by conducting a receiver-operating-characteristics (ROC) analysis. We determined the correlations between the ADCs and the prognostic markers and those of the FA values and the same markers.

Results:

The median ADCs of the benign and malignant lesions based on the ss-EPI were 1.57 and 1.2 × 10⁻³ mm²/sec, and those based on the rs-EPI were 1.53 and 1.09 × 10⁻³ mm²/sec, respectively. The area under the curve on the ROC analysis based on rs-EPI (0.924) was greater than that based on ss-EPI (0.897). There were no significant correlations between the ADCs and the prognostic markers, but there were significant correlations between the FA values and the estrogen receptor status, a proliferative marker, the nuclear grade and the intrinsic subtype.

Conclusion:

For breast cancer, DTI based on rs-EPI had superior diagnostic performance compared to DWI based on ss-EPI. Compared with the ADCs, the FA values were more closely correlated with prognostic markers of invasive breast cancer.

Pathological and radiological correlation in an autopsy case of combined pulmonary fibrosis and emphysema

We report an educational autopsy case of combined pulmonary fibrosis and emphysema. Radiological patterns of the upper lung were considered as mostly emphysema, but pathological observation revealed significant interstitial fibrosis of usual interstitial pneumonia as a major pathology. The patient eventually developed acute exacerbation of background interstitial pneumonia. Careful radiological and pathological correlation of the current case indicates that regions with distal acinar emphysema on computed tomography image may possess histologically marked dense fibrosis of lethal interstitial pneumonia.

Pleuroparenchymal fibroelastosis: Distinct pulmonary physiological features in nine patients

BACKGROUND

Pleuroparenchymal fibroelastosis (PPFE) is a rare idiopathic interstitial pneumonia defined by pleural and subpleural parenchymal fibrosis predominantly in the upper lobes. Although the radiological and pathological characteristics of PPFE have become increasingly recognized, its pulmonary physiological features are not well understood.

METHODS

We reviewed nine patients with radiologically and histologically proven PPFE, and evaluated pulmonary physiological data.

RESULTS

Of the nine patients, six were male and three were female. The median age at presentation was 61 years. Common symptoms were dyspnea on exertion, weight loss, and nonproductive cough. Recurrent pneumothorax was found in eight patients and pneumonia in four. Median pulmonary function test results were as follows: forced vital capacity, 55.4% predicted; total lung capacity (TLC), 67.1% predicted; residual volume (RV), 102.3% predicted; and RV/TLC, 143.6% predicted. RV/TLC was increased without evidence of small airway disease according to clinico-radiologic-pathologic evaluation. The median partial pressure of oxygen in arterial blood and the alveolar-arterial gradient of oxygen were within normal limits, although there was a slightly elevated partial pressure of carbon dioxide in arterial blood (PaCO2). PPFE progressed in all patients despite treatment with pirfenidone, corticosteroids, and immunosuppressive agents. Seven patients died during the follow-up, five because of hypercapnic respiratory failure.

CONCLUSIONS

PPFE is characterized by severe mechanical restriction with high RV/TLC, causing increased PaCO2 and eventual hypercapnic respiratory failure. These physiological findings may be useful as an adjunct in the diagnosis of PPFE.

Intratumoral heterogeneity of the distribution of kinetic parameters in breast cancer: comparison based on the molecular subtypes of invasive breast cancer

PURPOSE

To evaluate the distribution pattern of kinetic parameters in breast cancers with various molecular subtypes.

MATERIALS AND METHODS

This study was approved by institutional review board and was compliant with HIPAA. We classified 192 invasive breast cancers of 186 patients into four molecular subtypes using hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) results and evaluated the distribution pattern of kinetic parameters (percent volume of kinetic types relative to the tumor volume) in the molecular subtypes.

RESULTS

In the delayed phase, all three types of kinetic parameter (persistent, plateau, and washout pattern) were observed in each molecular subtype without any dominant type of kinetic parameter. The percentages of washout pattern in the HR+ and HER2- type and triple negative (TN) cancers tended to be lower than those in the other molecular subtype cancers.

CONCLUSION

Each molecular subtype of invasive breast cancer showed a heterogeneous kinetic pattern in dynamic-contrast magnetic resonance imaging (MRI). The HR+/HER2- cancers and the TN cancers had relatively lower percentages of washout pattern. When a manual assessment of the kinetic parameters is performed, close attention should be paid in order to identify the malignant washout kinetic pattern, particularly in HR+/HER2- cancer and TN cancer.

Visualization of the Superior Ophthalmic Veins by 3 Tesla 3D-TOF-MR Angiography

The superior ophthalmic veins (SOVs) are sometimes visualized on three-dimensional time-of-flight magnetic resonance (3D-TOF-MR) angiograms obtained with a 3 Tesla system. The purpose of this retrospective study was to determine the incidence of visualization of normal SOVs on 3D-TOF-MR angiograms, and their characteristic features. We reviewed 3D-TOF-MR angiograms of 345 consecutive patients obtained with a 3 Tesla MR device. Patients comprised 170 males and 175 females, aged five to 93 years. Most of the patients had, or were thought to have, cerebrovascular disease. The SOV was visualized in 13 of the 345 patients (3.8%). The visualized SOV was on the left side in seven of the 13, and on the right side in two. Both the right and left SOVs were visualized in four patients. The left SOV was more clearly visualized in two of these patients, whereas the SOVs were equally visible on both sides in the other two. There was a female predominance (M:F = 1:12) but no relation between age and visualization of SOVs. None of the visualized SOVs were dilated, and no dilated cavernous sinus was seen. The facial veins and angular veins were also visualized, continuing to the SOVs, suggesting rapid retrograde flow in the facial veins. SOVs are sometimes visualized on 3D-TOF-MR angiograms. This phenomenon should not be misdiagnosed as an asymptomatic dural carotid-cavernous fistula.

Abnormal Flow in the Cavernous Sinus Caused by an Asymptomatic Dural Arteriovenous Fistula of the Contralateral Transverse-Sigmoid Sinus

A 53-year-old asymptomatic man underwent cranial MR imaging to rule out cerebrovascular disease. On T2-weighted axial images abnormal flow voids were detected at the right cavernous sinus, suggesting a dural carotid-cavernous fistula (CCF). On the MR angiogram, abnormal high intensity signals were observed at the right cavernous sinus and the left transverse-sigmoid (T-S) sinus, suggestive of coexisting right dural CCF and dural arteriovenous fistula (AVF) of the left T-S sinus. Selective cerebral angiography of the left external carotid artery revealed abnormal flow in the right cavernous sinus caused by the dural AVF of the left T-S sinus via the right inferior petrosal sinus due to occlusion of both the distal left sigmoid sinus and proximal right internal jugular vein.

Middle cerebral artery occlusion causing intracerebral hemorrhage: radiologic findings

Middle cerebral artery (MCA) occlusion usually leads to cerebral infarction but rarely causes cerebral hemorrhage without infarction. We retrospectively investigated the unique radiographic manifestations in cases of cerebral hemorrhage without infarction. Computed tomography (CT) and angiographic images obtained in four patients (aged 26 to 70 years) with MCA occlusion associated with intracerebral hemorrhage were reviewed. Two patients also underwent magnetic resonance imaging (MRI), and one of these underwent magnetic resonance angiography as well; these images were also examined. Cranial CT revealed periventricular hemorrhage with ventricular penetration in one patient and with putaminal penetration in two. Solitary ventricular hemorrhage was found in the fourth patient. Angiography showed ipsilateral occlusion at the M1 portion of the MCA, accompanied by moyamoya-like vessels. No aneurysm or arteriovenous malformation was detected. MRI showed absence of the flow void in the affected MCA and an abnormal flow void in dilated collateral vessels in the basal ganglia. MCA occlusion can cause periventricular or ventricular hemorrhage, which appears to result from bleeding from fragile dilated collateral vessels and, thus, to have an etiology similar to that of adult moyamoya disease. MRI shows promise as a tool for evaluating the occlusion site.

Fenestration of the Middle Cerebral Artery Detected by MR Angiography

Unlike fenestration of the posterior cerebral arterial circulation, fenestration of the anterior cerebral arterial circulation has not been well described. We investigated the location and configuration of fenestration of the middle cerebral artery (MCA) detected by magnetic resonance (MR) angiography. We found 6 fenestrations of the MCA among cranial MR angiography images obtained from about 2,000 patients during the past 9 years at our institution using either of two 1.5T imagers. All images were obtained by the three-dimensional time-of-flight technique. Maximum-intensity projection images in the horizontal rotation view were displayed stereoscopically. All 6 fenestrations had small slit-like configurations, five located at the proximal M1 segment, the other, at the middle M1 segment. No associated aneurysm was found. Although MCA fenestration is extremely rare and cerebral artery fenestration usually has no clinical significance, an aneurysm can arise at the proximal end of the fenestration. Thus, recognizing MCA fenestration is important when interpreting cranial MR angiograms.

Acquired lesions of the corpus callosum: MR imaging

In this pictorial review, we illustrate acquired diseases or conditions of the corpus callosum that may be found by magnetic resonance (MR) imaging of the brain, including infarction, bleeding, diffuse axonal injury, multiple sclerosis, acute disseminated encephalomyelitis, Marchiafava-Bignami disease, glioblastoma, gliomatosis cerebri, lymphoma, metastasis, germinoma, infections, metabolic diseases, transient splenial lesion, dilated Virchow-Robin spaces, wallerian degeneration after hemispheric damage and focal splenial gliosis. MR imaging is useful for the detection and differential diagnosis of corpus callosal lesions. Due to the anatomical shape and location of the corpus callosum, both coronal and sagittal fluid-attenuated inversion recovery images are most useful for visualizing lesions of this structure.

Brainstem and cerebellar changes after cerebrovascular accidents: magnetic resonance imaging

We illustrate the various types of secondary degeneration in the brainstem and/or cerebellum detected on magnetic resonance (MR) images obtained after cerebrovascular accidents. The changes include: (a) ipsilateral nigral degeneration after striatal infarction; (b) Wallerian degeneration of the pyramidal tract in the brainstem after supratentorial pyramidal tract or motor cortex injury; (c) Wallerian degeneration of the corticopontine tract in the brainstem after frontal lobe infarction; (d) ipsilateral brainstem atrophy and crossed cerebellar atrophy due to an extensive supratentorial lesion; (e) ipsilateral superior cerebellar peduncle atrophy, contralateral rubral degeneration, contralateral inferior olivary degeneration and ipsilateral cerebellar atrophy after dentate nucleus hemorrhage; (f) ipsilateral inferior olivary degeneration after pontine tegmentum hemorrhage; (g) bilateral wallerian degeneration of the pontocerebellar tracts after ventromedial pontine infarction or basis pontis hemorrhage; and (h) ipsilateral cerebellar atrophy after middle cerebellar peduncle hemorrhage.