Prasad M. Panse

Usual interstitial pneumonia-pattern fibrosis in surgical lung biopsies. Clinical, radiological and histopathological clues to aetiology

Pulmonary fibrosis in surgical lung biopsies is said to have a ‘usual interstitial pneumonia-pattern’ (UIP-pattern) of disease when scarring of the parenchyma is present in a patchy, ‘temporally heterogeneous’ distribution. These biopsies are one of the more common non-neoplastic specimens surgical pathologists encounter and often pose a number of challenges. UIP is the expected histopathological pattern in patients with clinical idiopathic pulmonary fibrosis (IPF), but the UIP-pattern can be seen in other conditions on occasion. Most important among these are the rheumatic interstitial lung diseases (RILD) and chronic hypersensitivity pneumonitis (CHrHP). Because theses entities have different mechanisms of injury, approach to therapy, and expected clinical progression, it is imperative for the surgical pathologist to correctly classify them. Taken in isolation, the UIP-pattern seen in patients with IPF may appear to overlap with that of RILD and CHrHP, at least when using the broadest definition of this term (patchy fibrosis). However, important distinguishing features are nearly always present in our experience, and the addition of a multidisciplinary approach will often resolve the critical differences between these diseases. In this manuscript, we review the distinguishing clinical, radiologic and histopathological features of UIP of IPF, RILD and CHrHP, based, in part, on the existing literature, but also lessons learned from a busy lung biopsy consultation practice.

UIP diagnosed at surgical lung biopsy, 2000-2009: HRCT patterns and proposed classification system

OBJECTIVE High resolution CT (HRCT) is diagnostic of usual interstitial pneumonia (UIP) if honeycombing is present. However, biopsy-proven UIP also occurs in patients without honeycombing. Identification of specific HRCT patterns may enable specific diagnosis and allow more patients to enter clinical trials. Pattern may also predict prognosis. We sought to identify specific HRCT patterns in patients with biopsy-proven UIP (2000-2009) and to assess outcomes and serial change in pattern. MATERIALS AND METHODS We reviewed the HRCT findings in 44 patients with biopsy-proven UIP and identified four distinct patterns: classic UIP (cUIP) with honeycombing, fibrosis without honeycombing (FnoH), minimal fibrosis (Fmin), and ground-glass present (GGOp). We reviewed electronic medical records for outcome information and serial HRCT examinations when available. RESULTS The extent of fibrosis varied between patterns; findings were always heterogeneous in the cUIP and FnoH patterns. Some Fmin patients had a more homogeneous appearance. The lower lobes were predominantly affected, but upper lobe abnormalities were always present. Mortality from respiratory failure and acute exacerbations occurred regardless of pattern. Serial progression from Fmin to FnoH to cUIP occurred, although in a variable manner. Some individuals had an acute illness (GGOp) as the initial manifestation of UIP. CONCLUSION The FnoH pattern may be diagnostic of UIP in the proper clinical setting; heterogeneity of HRCT appearance is critical and has not been previously emphasized. Grouping of patients on the basis of pattern may allow more accurate assessment of treatment effects. Further validation and study of these HRCT patterns is warranted. Histologic UIP predicts clinical course.

Relationship of contrast-enhanced magnetic resonance imaging-derived intramural scar distribution and speckle tracking echocardiography-derived left ventricular two-dimensional strains

AIMS Information is limited regarding the functional correlates of intramural scar burden in myopathic hearts. We aimed to explore the use of speckle tracking echocardiography selectively at three intramural locations, to investigate the variance in cardiac strains and their relationship to contrast-enhanced magnetic resonance imaging-derived scar distribution and global left ventricular systolic function. METHODS AND RESULTS Fifty-nine patients with evidence of myocardial fibrosis on contrast-enhanced magnetic resonance imaging and 18 healthy subjects underwent speckle tracking echocardiography for measuring subendocardial, midmyocardial, and subepicardial strains in longitudinal, circumferential, and radial directions. Patients were divided into three categories of scar distribution: Group A, endocardial and midmyocardial; Group B, midmyocardial and epicardial; and Group C, transmural. When these patients were compared with 18 healthy control subjects, longitudinal left ventricular deformation was attenuated equally for all three groups, whereas circumferential strain was relatively well preserved. On multivariate analysis, circumferential strain and scar burden were independent determinants of left ventricular ejection fraction (R(2) = 0.57; P = 0.003 for strain burden and P = 0.01 for scar burden). CONCLUSION Longitudinal strains are attenuated independent of myocardial scar location. This alteration in left ventricular deformation is associated with circumferential mechanics becoming a key determinant of global left ventricular pump function in myopathic hearts.

Symptomatic pericardial cyst: a case series

Pericardial cysts are most commonly located at the cardiophrenic angle or, rarely, in the posterior or anterior superior mediastinum. The majority of pericardial cysts are asymptomatic and are found incidentally. Symptomatic pericardial cysts present with dyspnoea, chest pain, or persistent cough. We describe four patients with symptomatic pericardial cysts who were treated with either echocardiographically guided percutaneous aspiration or video-assisted thoracoscopic surgery, or both; thoracotomy; or conservative therapy.

Multimodality imaging showing complete cardiovascular involvement by Erdheim-Chester disease.

Erdheim-Chester disease (ECD) is a multisystem non-Langerhans form of cell histiocytosis. Histiocytic infiltration leads to xanthogranulomatous infiltrates of multiple organ systems. Erdheim-Chester disease was first reported in 1930, only 320 cases reported in the literature. Cardiac involvement in ECD carries worst prognosis beside the central nervous system. We report the first case with pan-cardiac involvement diagnosed with multimodality imaging.

Diagnosis of Usual Interstitial Pneumonitis in the Absence of Honeycombing: Evaluation of Specific CT Criteria With Clinical Follow-Up in 38 Patients

OBJECTIVE We sought to evaluate specific CT criteria for the diagnosis of usual interstitial pneumonitis (UIP) in the absence of honeycombing. These criteria included peripheral reticulation and lobular distortion; some upper lobe involvement, but a lower zone predominance; a heterogeneous appearance with areas of normal lung, minimal reticulation, and substantial distortion alternating throughout the study and often on an individual image; a nonsegmental distribution; and traction bronchiectasis. MATERIALS AND METHODS We searched reports of CT studies performed between January 1, 2009, and January 1, 2012, to identify patients for whom UIP was a likely or probable diagnosis and reviewed the CT study for each case (n = 106). There were 38 patients who met all CT criteria and who also had a clinical diagnosis of idiopathic UIP (also known as idiopathic pulmonary fibrosis [IPF]) and follow-up of at least 6 months, as determined from the electronic medical record. We reviewed prior and subsequent CT examinations in this cohort. RESULTS The median age of our patients was 80 years, and the duration of clinical follow-up was 6-104 months (mean, 38 months; median, 37 months). For all patients, a pulmonary medicine physician made a working diagnosis of IPF. Fifteen patients died from pulmonary complications, and 16 of the surviving patients had clinical or functional progression of disease. There were no instances in which the initial diagnosis was revised or reversed. CONCLUSION Strict application of specific CT criteria may allow a specific diagnosis of UIP in the proper clinical setting in the absence of honeycombing.

Coronary calcium quantification using contrast-enhanced dual-energy computed tomography scans.

The purpose of this study is to evaluate a direct measure of calcium burden by using dual‐energy computed tomography (DECT) during contrast‐enhanced coronary imaging, potentially eliminating the need for an extra noncontrast X‐ray acquisition. The ambiguity of separation of calcium from contrast material on contrast‐enhanced images was solved by using virtual noncontrast images obtained by DECT. A new threshold CT number was required to detect the calcium carrying potential risk for adverse coronary events on virtual noncontrast images. Two methods were investigated to determine the 130 HU threshold for DECT scoring. An in vitro anthropomorphic phantom with 29 excised patient calcium plaques inserted was used for both a linear and a logistic regression analysis. An IRB approved in vivo prospective study of six patients was also performed to be used for logistic regression analysis. The threshold found by logistic regression model to define the calcium burden on virtual noncontrast images detects the calcium carrying potential risk for adverse coronary events correctly (2.45% error rate). DECT calcium mass and volume scores obtained by using the threshold correlates with both conventional Agatston and volume scores (r=0.98,p<0.001). A conventional CT cardiac exam requires two scans, including a noncontrast scan for calcium quantification and a contrast‐enhanced scan for coronary angiography. With the ability to quantify calcium on DECT contrast‐enhanced images, a DECT cardiac exam could be accomplished with one contrast‐enhanced scan for both calcium quantification and coronary angiography. PACS numbers: 87.57.Q, 87.57.N

Constrictive pericarditis and restrictive cardiomyopathy in the modern era

The differentiation between constrictive pericarditis and restrictive cardiomyopathy can be clinically challenging. Pericardial constriction results from scarring and consequent loss of pericardial elasticity leading to impaired ventricular filling. Restrictive cardiomyopathy is characterized by a nondilated rigid ventricle, severe diastolic dysfunction and restrictive filling producing hemodynamic changes, similar to those in constrictive pericarditis. While constrictive pericarditis is usually curable by surgical treatment, restrictive cardiomyopathy requires medical therapy and in appropriate patients, the definitive treatment is cardiac transplantation. Sufficient differences exist between the two conditions to allow noninvasive differentiation, but no single diagnostic tool can be relied upon to make this distinction. Newer echocardiographic techniques such as speckle-track imaging, velocity vector imaging, as well as cardiac computed tomography and cardiac MRI can help differentiate constriction from restriction with high sensitivity and specificity. Outcomes are better with early diagnosis of constriction in particular and early surgical resection.

Hypoplasia, pseudocoarctation and coarctation of the aorta - a systematic review.

Aortic arch abnormalities are uncommon and may be seen in association with other congenital cardiac anomalies. Coarctation, pseudocoarctation and hypoplastic aortic arch are known aortic arch abnormalities, with the former being well studied, whilst for the latter two, much less is known. There are similarities and differences that are important to distinguish among these three conditions in order to avoid errors in diagnosis that may result in unnecessary investigations, which may in turn result in physical or emotional harm to the patient. For this reason, we present a systematic review of the published literature providing an evidence-based overview that may be helpful to clinicians when faced with this diagnostic dilemma.

Non-Calcified Coronary Atherosclerotic Plaque Characterization by Dual Energy Computed Tomography

Coronary heart disease (CHD) is the most prevalent cause of death worldwide. Atherosclerosis which is the condition of plaque buildup on the inside of the coronary artery wall is the main cause of CHD. Rupture of unstable atherosclerotic coronary plaque is known to be the cause of acute coronary syndrome. Vulnerability of atherosclerotic plaque has been related to a large lipid core covered by a fibrous cap. Non-invasive assessment of plaque characterization is necessary due to prognostic importance of early stage identification. The purpose of this study is to use the additional attenuation data provided by dual energy computed tomography (DECT) for plaque characterization. We propose to train supervised learners on pixel values recorded from DECT monochromatic X-ray and material basis pairs images, for more precise classification of fibrous and lipid plaques. The interaction of the pixel values from different image types is taken into consideration, as single pixel value might not be informative enough to separate fibrous from lipid. Organic phantom plaques scanned in a fabricated beating heart phantom were used as ground truth to train the learners. Our results show that support vector machines, artificial neural networks and random forests provide accurate results both on phantom and patient data.