Diseases of the nose and pharynx Allergic rhinitis (hay fever) commonly affects the nose, paranasal sinuses and nasopharynx and can predispose to inflammatory nasal polyps ( Fig. 12.1 ). The sinonasal (Schneiderian) papilloma is particular to the nasal cavity and…
The cardiovascular system includes the heart, blood vessels and circulating blood and is often referred to as the circulatory system. In this chapter, we will focus upon diseases affecting the blood vessels (the arteries and veins) and the heart. Diseases…
Introduction When there is sustained occlusion of arterial blood supply or venous drainage, a type of necrosis can occur called infarction . Common clinical examples of infarction are myocardial infarction (affecting the heart) and cerebral infarction or stroke (affecting the…
Thrombosis The vascular system normally contains fluid blood. However, it is often necessary for blood to coagulate to prevent bleeding following injury to a vessel wall. To control this process of haemostasis , there are interacting systems that either promote…
The wall of an artery has three layers, the intima, media and adventitia, which are separated from each other by thin elastic fibres known as the elastic laminae ( E-Fig. 8.1 ). The intima, the innermost layer, is composed of…
Cellular atypia and dysplasia In the previous chapter, we considered cellular adaptations to a variety of stimuli resulting in alterations in their pattern of growth, whilst still achieving full differentiation Occasionally, cells have an increased rate of division such that…
Introduction Cells exist in, and must adapt to, an environment that is continually changing, reflecting not only physiological processes but also external influences such as drugs or toxins. As briefly discussed in Ch. 2 , if the stimulus is overwhelming,…
Introduction A number of infections may be diagnosed from the characteristic appearances seen in biopsy specimens. In some cases, the diagnosis may first be suspected when a biopsy is examined by light microscopy. In other cases, the clinician suspects an…
Introduction In developed countries, where the major pyogenic infections have been brought more or less under control, chronic inflammatory conditions result in a huge burden of morbidity and mortality. In less industrialised countries, certain infections, such as tuberculosis, typically cause…
Introduction Inflammation is an almost universal response to tissue damage by a wide range of harmful stimuli, including mechanical trauma, tissue necrosis and infection. The purpose of inflammation is to destroy (or contain) the damaging agent, initiate repair processes and…