Glossitis is usually very painful, and there may be erosions present in the depths of the fissures. Similar fissured lesions which are not associated with HSV, as may occur in fissured tongue, do not tend to be painful. The name comes from the geometric pattern of the fissures which are longitudinal, crossed or branched. It is described as occurring in immunocompromized persons, e.g. who have leukemia. However, the association between herpes simplex and geometric glossitis is disputed by some due to a lack of gold standard techniques for diagnosis of intraoral herpetic lesions, and the high prevalence of asymptomatic viral shedding
The Canon of Medicine anatomy, and physiology. The book explains the causes of health and disease. Avicenna believed that the human body cannot be restored to health unless the causes of both health and disease are determined. He defined medicine ("tibb") as follows: Avicenna begins part one by dividing theoretical medicine and medical practice. He describes what he says are the "four causes" of illness, based on Aristotelian philosophy: The material cause, the efficient cause, the formal cause, and the final cause: Avicenna's thesis on the elements of the cosmos is described by Gruner as "the foundation of the whole "Canon"". Avicenna insists here