Continued damage to the optic nerve results in the development of optic atrophy, classically seen as temporal pallor of the optic disc. Cause
Toxic optic neuropathy
There are several causes of toxic optic neuropathy. Among these are: ingestion of methanol (wood alcohol), ethylene glycol (automotive antifreeze), disulfiram (used to treat chronic alcoholism), halogenated hydroquinolones (amebicidal medications), ethambutol and isoniazid (tuberculosis treatment), and antibiotics such as linezolid and chloramphenicol as well as chloroquine and the related hydroxychloroquine (for lupus and rheumatoid arthritis) where it is known as chloroquine retinopathy. Tobacco is also a major cause of toxic optic neuropathy. Nutritional optic neuropathy
The predominant cause of nutritional optic neuropathy is thought to be deficiency of B-complex vitamins, particularly thiamine (vitamin B1), cyanocobalamin (vitamin B12) and recently copper. Deficiency of pyridoxine (vitamin B6), niacin (vitamin B3), riboflavin (vitamin B2), and/or folic acid also seems to play a role. Those individuals who consume excessive amounts of alcohol and use tobacco are at greater risk because they tend to be malnourished. Those with pernicious anemia are also at risk due to an impaired ability to absorb vitamin B12 from the intestinal tract. Pathophysiology
All of the above risk factors impact mitochondrial oxidative phosphorylation. Thus, the toxic and nutritional optic neuropathies are actually acquired mitochondrial optic neuropathies. The clinical picture that they produce is akin to that of the congenital mitochondrial optic neuropathies, e.g., Lebers hereditary optic neuropathy and Kjers optic neuropathy. Diagnosis
The diagnosis of toxic or nutritional optic neuropathy is usually established by a detailed medical history and careful eye examination.
Hypochondriasis or hypochondria is a condition in which a person is excessively and unduly worried about having a serious illness. An old concept, the meaning of hypochondria has repeatedly changed. It has been claimed that this debilitating condition results from an inaccurate perception of the condition of body or mind despite the absence of an actual medical diagnosis. An individual with hypochondriasis is known as a hypochondriac. Hypochondriacs become unduly alarmed about any physical or psychological symptoms they detect, no matter how minor the symptom may be, and are convinced that they have, or are about to be diagnosed with, a serious illness.Often, hypochondria persists even after a physician has evaluated a person and reassured them that their concerns about symptoms do not have an underlying medical basis or, if there is a medical illness, their concerns are far in excess of what is appropriate for the level of disease. It is also referred to hypochondriaism which is the act of being in a hypochondriatic state, acute hypochondriaism. Many hypochondriacs focus on a particular symptom as the catalyst of their worrying, such as gastro-intestinal problems, palpitations, or muscle fatigue. To qualify for the diagnosis of hypochondria the symptoms must have been experienced for at least 6 months.International Classification of Diseases (ICD-10) classifies hypochondriasis as a mental and behavioral disorder. In the Diagnostic and Statistical Manual of Mental Disorders, DSM-IV-TR defined the disorder, "Hypochondriasis", as a somatoform disorder and one study has shown it to affect about 3% of the visitors to primary care settings.