Medicine Hack

  DEFINITION   It is an upper respiratory tract illness that comprises of rhinorrhea and nasal obstruction as the main symptoms.   EPIDEMIOLOGY   5- 7 times/ year in children and 2-3 times/ year in adults. most commonly seen between the early fall and late spring in temperate climates. Transmission of the virus may occur via direct contact, large-particle aerosol, or small-particle aerosol.   MICROBIOLOGY   The rhinoviruses are usually responsible for the majority of cases. Coronavirus, respiratory syncytial virus and metapneumovirus may also be associated with the common cold syndrome.   DIAGNOSIS   The diagnosis of the common cold is a clinical diagnosis. Polymerase chain reaction assay can determine the responsible pathogen but this is rarely useful in the management of the patient.   THERAPY   Management is mainly directed towards the bothersome symptoms as no specific antiviral agents are useful in the treatment. First published on: 10 June 2016

 PENETRATION  Penetration is one of the five technical factors that help you in determining whether a radiograph is technically adequate.  ADEQUATE PENETRATION  If a frontal chest radiograph is adequately penetrated, you should be able to see the thoracic spine through the heart shadow. In the radiograph above, we can see the thoracic spine through the heart shadow (solid white line).  UNDER PENETRATION  It means that the penetration is inadequate. The radiograph will appear as too white. We will not be able to see the thoracic spine through the heart. This can lead us into making interpretation errors. 1) The pulmonary markings may appear more prominent and these can be mistaken for being due to a congestive heart failure or pulmonary fibrosis. 2) The left lung base will appear opaque thus obscuring the left hemidiaphragm. This can mimic or hide a true disease in the left lower lung field e.g. left lower lobe pneumonia or left pleural effusion. To avoid these misin