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Endomysium, Perimysium and epimysium - definition, histology

Each muscle fibre is closely surrounded by connective tissue. This acts as a support for the muscle fibres and unites them to each other. 1) Each muscle fibres is surrounded by delicate connective tissue that is called the endomysium . 2) Individual fasciculi are enclosed by a stronger sheath of connective tissue called the perimysium . 3) The entire muscle is surrounded by connective tissue called the epimysium . This is illustrated by the schematic diagram below. 1= perimysium, 2= endomysium, 3= fasciculus. At the junction of a muscle with a tendon, the fibres of the endomysium, the perimysium and the epimysium become continuous with the fibres of the tendon. First published on: 27 December 2016

Chronic sinusitis - Steam inhalation not effective, nasal irrigation may help

  DEFINITION  Chronic sinusitis refers to inflammation the paranasal sinuses for a period of at least 12 weeks. The most important cause of chronic sinusitis is failure of acute infections to resolve.   PATHOPHYSIOLOGY  Acute infection destroys the normal ciliated epithelium, thus impairing drainage from the sinuses. There is pooling and stagnation of secretions in the sinuses which favours infections. Persistence of infection causes mucosal changes, such as loss of cilia, edema and polyp formation. We eventually have a vicious cycle.   CLINICAL FEATURES  Patients may complain of blocked nose, runny nose, headache and a reduced sense of smell (hyposmia). Foul-smelling discharge suggests anaerobic infection. Some people will also have nasal polyps.   TREATMENT  1) We should always search for underlying aetiological factors which obstruct sinus drainage and ventilation. 2) A work-up for nasal allergy may be required. 3) Culture and sensitivity of sinus discharge helps in t

The common cold - definition, diagnosis and treatment

  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

Reading chest radiograph - Penetration

 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

BMI versus waist to hip ratio

 DEFINITION  Obesity is a state of excess adipose tissue mass. It is often viewed as equivalent to an increased body weight. This is not true because muscular individuals may have increased body weight but are not obese. Weight follows a continuous distribution pattern in human population. The point at which mortality and morbidity becomes statistically significant is the cut-off to call a patient obese.  METHODS  Various methods have been used to measure obesity. These include: 1) Anthropometry (skin-fold thickness) 2) Densitometry (underwater weighing) 3) CT/MRI 4) Electrical impedance. Still the most common techniques used in clinical practice are: 1) BMI measurement 2) Waist-to-hip ratio measurement.  BMI  It is not an accurate measure of obesity but since it is simple to calculate, it is the most frequently measured parameter. At similar BMI, women usually have more fat than men. When the BMI > 25 Kg/m2, morbidity starts to increase and if associated with ris

Alcoholic liver disease

 INTRODUCTION  Chronic and excessive use of alcohol is one of the major causes of liver disease. 90% of daily heavy drinkers (>60 g alcohol/day) as well as binge drinkers have fatty liver but a smaller percentage (10-35%) of drinkers progress to alcoholic hepatitis which is a precursor for cirrhosis. The long-term risk is 9 times higher in patients with alcoholic hepatitis compared to those with fatty liver alone. Some population-based surveys have documented that men must drink 40 to 80 g of alcohol daily and women must drink 20 to 40 g daily for 10 to 12 years to achieve a significant risk of liver disease. Liver pathology consists of  3 major lesions  that are progressive and rarely exist in a pure form: 1) fatty liver (usually reverses quickly with abstinence), 2) alcoholic hepatitis and 3) cirrhosis. Prognosis of severe alcoholic liver disease (ALD) is bad. Mortality of patients with alcoholic hepatitis concurrent with cirrhosis id nearly 60% at 4 years. Alt

Voltaire - Medical quote no longer valid

Times have changed Monsieur Voltaire. Your quote is no longer valid in our "Evidence Based Medicine" world. The quote's accuracy is stunning though if applied to quacks. Our advice to young practitioners : DO NOT BLINDLY FOLLOW WHAT A SENIOR DOCTOR IS DOING. Try to  understand why he did something for that specific problem. Always ask if you do not understand. Article resources: 1)  "Voltaire lisant L’année littéraire de Fréron", huile sur toile de Jacques Augustin Catherine Pajou, 1811 Last reviewed on: 2 September 2015