Cystic lung diseases: radiological aspects.

Cystic lung diseases (CLDs) are a heterogeneous group of pathophysiological entities comprising gas-filled lesions with imperceptible walls, which can occur throughout lung parenchyma. CLDs can arise from different mechanisms and may often have an unpredictable progression. As CLDs are infrequent and may be associated to many different processes, they pose a diagnostic challenge to the radiologist and referring physician. CLDs require a comprehensive diagnostic approach. An essential tool in the evaluation of CLDs is high-resolution computed tomography (HRCT). The first step is in distinction from true cysts, from other cysts mimicking entities, as emphysema, honeycombing, pneumatocoele, cavitate nodules, or bronchiectasis. Thereafter the identification of number, distribution, wall size, and other systemic manifestations provides an accurate characterisation of CLD, often avoiding further evaluation with lung biopsy. Features of pulmonary lucencies, classification of CLDs based on pathophysiological mechanisms, and radiological criteria, the less common aetiologies, and a multidisciplinary approach in pulmonary cysts are reported. Finally, a systematic diagnostic algorithm to guide radiologists in the evaluation of CLDs is discussed.

DPO: Diffuse Pulmonary Ossification - A Diagnostic Challenge.

Diffuse pulmonary ossification (DPO) is a rare condition of DLD (diffuse lung disease) characterized by the presence of metaplastic ectopic bone in the lungs and is less frequent in patients without a clear background of lung diseases. DPO is characterized by very small calcific nodules, often with bone mature located in both lungs and often in peripheral areas of the lungs. Two patterns of DPO have been recognized dendriform and nodular. The dendriform type is less common and is characterized by a coral-like network of bone spiculae along the alveolar septa and is often related to interstitial fibrosis or chronic obstructive lung disease [1]. Recent literature papers indicate that DPO may be a predictor of pulmonary fibrosis, is related to Usual Interstitial Pneumonia (UIP) pattern, and has a higher correlation with Idiopathic Pulmonary Fibrosis (IPF). We present a case of a 41-years-old male with persistent bronchitis who underwent a chest X-ray (CXR) that showed multiple pulmonary small calcified nodules in both lungs. These findings were then defined with a high-resolution computed tomography of the chest (HRCT) that showed multiple small nodules spread in both lungs with a "tree-like pattern". A lung biopsy was performed to confirm the radiological diagnostic hypothesis of DPO, and further pathological examination showed multifocal areas of mature bone tissue within the lung parenchyma.

The Many Faces of Covid-19: Organizing Pneumonia (OP) Pattern HRCT Features.

Covid-19 (coronavirus disease 2019) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). On 30 January 2020 the World Health Organization (WHO) declared that the outbreak of Covid-19 realizes a public health emergency of international concern. Because of the primary involvement of the respiratory system, chest CT is strongly recommended in suspected Covid-19 cases, for both initial and follow-up. We present the case of a Covid-19 patient, a 57-year-old man, with a typical HRCT course of OP reaction.

Sonographic determination of renal volume.

The volume of three canine and 34 human kidneys was calculated based on a three-dimensional ellipsoid formula. Following nephrectomy, renal volume was measured by water displacement and/or estimated by determination of renal mass. Linear regression of ultrasound volume with the water-displacement volume and renal mass was ascertained, and the coefficient of determination was calculated. Based on water-displacement measurements, the ellipsoid formula was modified empirically.