Emphysema, or pulmonary emphysema, is a lower respiratory tract disease, characterised by air-filled spaces (pneumatoses) in the lungs, that can vary in size and may be very large. The spaces are caused by the breakdown of the walls of the alveoli and they replace the spongy lung parenchyma. This reduces the total alveolar surface available for gas exchange leading to a reduction in oxygen supply for the blood. Emphysema usually affects the middle aged or older population because it takes time to develop with the effects of tobacco smoking, and other risk factors. Alpha-1 antitrypsin deficiency is a genetic risk factor that may lead to the condition presenting earlier.When associated with significant airflow limitation, emphysema is a major subtype of chronic obstructive pulmonary disease (COPD), a progressive lung disease characterized by long-term breathing problems and poor airflow. Without COPD, the finding of emphysema on a CT lung scan still confers a higher mortality risk in tobacco smokers. In 2016 in the United States there were 6,977 deaths from emphysema – 2.2 per 100,000 of the population. Globally it accounts for 5% of all deaths. A study on the effects of tobacco and cannabis smoking showed that a possibly cumulative toxic effect could be a risk factor for developing emphysema, and spontaneous pneumothorax.There are four types of emphysema, three of which are related to the anatomy of the lobules of the lung – centrilobular or centriacinar, panlobular or panacinar, and paraseptal or distal acinar emphysema, and are not associated with fibrosis (scarring).
Phthisis bulbi is a shrunken, non-functional eye. It may result from severe eye disease, inflammation or injury, or it may represent a complication of eye surgery. Treatment options include insertion of a prosthesis, which may be preceded by enucleation of the eye. Symptoms
The affected eye is shrunken, and has little to no vision. The intraocular pressure in the affected eye is very low or nonexistent. The layers in the eye may be fused together, thickened, or edematous. The eyelids may be glued shut. The eye may be soft when palpated. Under a microscope there may be deposits of calcium or bone, and the cornea is often affected by cataracts. Causes
It can be caused by injury, including burns to the eye, or long-term eye disease or inflammation. End-stage glaucoma can cause it. It can often complicate eye surgery. Other common causes include cancer, retinal detachment, vascular lesions, infection, and inflammation. Treatment
Treatment for the affected eye is often futile. Usually, treatment is to end the pain in the affected eye and for cosmetic purposes, not to restore vision. It can be removed, a procedure called enucleation of the eye. Sometimes, though, it is possible to transplant only parts of the eye, and some vision can be restored. References


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