Asthenopia (aesthenopia) or eye strain is an ophthalmological condition that manifests itself through nonspecific symptoms such as fatigue, red eyes, eye strain, pain in or around the eyes, blurred vision, headache and occasional double vision. Symptoms often occur after reading, computer work, or other activities that involve tedious visual tasks.
When concentrating on a visually intense task, such as continuously focusing on a book or computer monitor, the inner eye muscles may tighten, which can cause the eyes to get irritated, dry, and uncomfortable. Giving the eyes a chance to focus on a distant object at least once an hour usually alleviates the problem.
On a computer, a CRT with a low refresh rate (less than 70 Hz) can cause similar problems because of the flickering image. Aging CRTs also often go slightly out of focus, and this can also cause eye strain. LCDs do not go out of focus and are less susceptable to visible flicker.
Causes of Asthenopia
Sometimes, asthenopia (aesthenopia) can be due to specific visual problems, such as uncorrected refraction errors or binocular vision problems like accommodative insufficiency or heterophoria.
Homeopathy Treatment for read more [...]
Amblyopia, otherwise known as lazy eye, is a disorder of the visual system that is characterized by poor or indistinct vision in an eye that is otherwise physically normal, or out of proportion to associated structural abnormalities. It has been estimated to affect 1–5% of the population.
The problem is caused by either no transmission or poor transmission of the visual image to the brain for a sustained period of dysfunction or during early childhood. Amblyopia normally only affects one eye, but it is possible to be amblyopic in both eyes if both are similarly deprived of a good, clear visual image. Detecting the condition in early childhood increases the chance of successful treatment.
While the colloquialism “lazy eye” is frequently used to refer to amblyopia, the term is inaccurate because there is no “laziness” of either the eye or the amblyope involved in the condition.
Amblyopia is a developmental problem in the brain, not an organic problem in the eye (although organic problems can induce amblyopia which persist after the organic problem has resolved). The part of the brain corresponding to the visual system from the affected eye is not read more [...]
Amaurosis (Greek meaning darkening, dark, or obscure) is vision loss or weakness that occurs without an apparent lesion affecting the eye . It may result from either a medical condition or from excess acceleration, as in flight. The term is the same as the Latin gutta serena.Types of Amaurosis Leber’s congenital amaurosis is an inherited disease resulting in optic atrophy and secondary severe vision loss or blindness. It was first described by Theodore Leber in the 19th century.Amaurosis fugax (Latin: fugax meaning fugitive) is a temporary loss of vision in one eye caused by decreased blood flow (ischemia) to the retina. Another cause is the presence of emboli located in the ipsilateral (same side) internal carotid artery. It is a type of transient ischaemic attack (TIA). Those experiencing Amaurosis usually experience complete symptom abeyance within a few minutes. In a small minority of those who experience Amaurosis, stroke or vision loss has resulted. Diabetes, hypertension and smoking are factors known to increase the risks of suffering this condition. It also can be the result of surgical repair to the mitral valve, when very small emboli may break away from the site read more [...]
Addison’s disease (also known as chronic adrenal insufficiency, hypocortisolism or hypocorticism) is a rare endocrine disorder in which the adrenal gland produces insufficient amounts of steroid hormones (glucocorticoids and often mineralocorticoids). It may develop in children as well as adults, and may occur as the result of a large number of underlying causes. The condition is named after Dr Thomas Addison, the British physician who first described the condition in his 1855 publication On the Constitutional and Local Effects of Disease of the Suprarenal Capsules. The adjective “Addisonian” is used for features of the condition, as well as patients with Addison’s disease.
The condition is generally diagnosed with blood tests, medical imaging and additional investigations. Treatment involves replacement of the hormones (oral hydrocortisone and fludrocortisone). If the disease is caused by an underlying problem, it may be possible to address. Regular follow-up and monitoring for other health problems is necessary.
Signs and symptoms of Addison’s disease
The symptoms of Addison’s disease develop insidiously, and it may take some time to be recognized. read more [...]
Ascariasis is a human disease caused by the parasitic roundworm Ascaris lumbricoides. Perhaps as many as one quarter of the world’s people are infected, and ascariasis is particularly prevalent in tropical regions and in areas of poor hygiene. Other species of the genus Ascaris are parasitic and can cause disease in domestic animals.
Infection occurs through ingestion of food contaminated with feces containing Ascaris eggs. The larvae hatch, burrow through the intestine, reach the lungs, and finally migrate up the respiratory tract. From there they are then reswallowed and mature in the intestine, growing up to 30 cm (12 in.) in length and anchoring themselves to the intestinal wall.
Infections are usually asymptomatic, especially if the number of worms is small. They may however be accompanied by inflammation, fever, and diarrhea, and serious problems may develop if the worms migrate to other parts of the body.
Roughly 1.5 billion individuals are infected with this worm, primarily in Africa and Asia. Ascariasis is endemic in the United States including Gulf Coast; in Nigeria and in Southeast Asia. One study indicated that the prevalence of ascariasis in read more [...]
Acromegaly (from Greek akros “extreme” or “extremities” and megalos “large” – extremities enlargement) is a syndrome that results when the pituitary gland produces excess growth hormone (hGH) after epiphyseal plate closure. A number of disorders may be affecting the pituitary to create this circumstance, although most commonly it involves a GH producing tumor derived from a distinct type of cells (somatotrophs) and called pituitary adenoma.
Acromegaly most commonly affects adults in middle age, and can result in severe disfigurement, serious complicating conditions, and premature death if unchecked. Because of its insidious pathogenesis and slow progression, the disease is hard to diagnose in the early stages and is frequently missed for many years, when changes in external features, especially of the face, become noticeable.
Acromegaly is often also associated with gigantism.
Symptoms of Acromegaly
Features that result from high level of hGH or expanding tumor include:
Soft tissue swelling visibly resulting in enlargement of the hands, feet, nose, lips and ears, and a general thickening of the skin
Soft tissue swelling of internal organs, notably read more [...]
Hypothyroidism is the disease state in humans and animals caused by insufficient production of thyroid hormone by the thyroid gland. Cretinism is a form of hypothyroidism found in infants.Causes of Hypothyroidism
About three percent of the general population is hypothyroid. Factors such as iodine deficiency or exposure to Iodine-131 (I-131) can increase that risk. There are a number of causes for overt hypothyroidism. Historically, and still in many developing countries, iodine deficiency is the most common cause of hypothyroidism worldwide. In iodine-replete individuals, hypothyroidism is mostly caused by Hashimoto’s thyroiditis, or by a lack of the thyroid gland or a deficiency of hormones from either the hypothalamus or the pituitary.Hypothyroidism can result from postpartum thyroiditis, a condition that affects about 5% of all women within a year after giving birth. The first phase is typically hyperthyroidism. Then, the thyroid either returns to normal or a woman develops hypothyroidism. Of those women who experience hypothyroidism associated with postpartum thyroiditis, one in five will develop permanent hypothyroidism requiring life-long treatment.Hypothyroidism can read more [...]
Graves’ disease is a thyroid disorder characterized by goitre, exophthalmos, and hyperthyroidism. It is caused by an antibody-mediated auto-immune reaction as to form anti-TSH-Receptor antibody. However, the trigger for this reaction is still unknown. It is the most common cause of hyperthyroidism in the world, and the most common cause of general thyroid enlargement in developed countries.
In some parts of Europe the term Basedow’s disease or Graves-Basedow disease is preferred to Graves’ disease. It was also historically referred to as exophthalmic goiter.
Graves’ disease owes its name to the Irish doctor Mathew Graves , who described a case of goiter with exophthalmos in 1835. However, the German Karl Adolph von Basedow independently reported the same constellation of symptoms in 1840. As a result, on the European Continent the term Basedow’s disease is more common than Graves’ disease.
Several earlier reports exist but were not widely circulated. For example, cases of goiter with exophthalmos were published by the Italians Giuseppe Flajina and Antonio Giuseppe Testicle, in 1802 and 1810 respectively. Prior to these, Caleb Hillier Parry, a read more [...]
A goitre (BrE), or goiter (AmE) (Latin struma), also called a bronchocele, is a swelling in the neck (just below the Adam’s apple or larynx) due to an enlarged thyroid gland.
Classification of Goitre
They are classified in different ways:
A “diffuse goiter” is a goiter that has spread through all of the thyroid (and can be a “simple goitre”, or a “multinodular goitre”).
“Toxic goitre” refers to goitre with hyperthyroidism. These most commonly due to Graves’ disease, but can be caused by inflammation or a multinodular goitre.
“Nontoxic goitre” (associated with normal or low thyroid levels) refers to all other types (such as that caused by lithium or certain other autoimmune diseases).
Other type of classification:
I – palpation struma – in normal posture of head it cannot be seen. Only found when palpating.
II – struma is palpative and can be easily seen.
III – struma is very big and is retrosternal. Pressure and compression marks.
Causes of Goitre
Other causes are:
Hashimoto’s thyroiditis (E06.3)
Graves-Basedow disease (E05.0)
Inborn errors of thyroid hormone synthesis, causing congenital hypothyroidism read more [...]
Diabetes insipidus (DI) is a condition characterized by excretion of large amounts of severely diluted urine, which cannot be reduced when fluid intake is reduced. It denotes inability of the kidney to concentrate urine. DI is caused by a deficiency of antidiuretic hormone (ADH), also known as vasopressin, due to the destruction of the back or “posterior” part of the pituitary gland where vasopressin is normally released from, or by an insensitivity of the kidneys to that hormone. It can also be induced iatrogenically by various drugs.
Signs and symptoms of Diabetes insipidus
Excessive urination and extreme thirst (especially for cold water and sometimes ice or ice water) are typical for DI. Symptoms of diabetes insipidus are quite similar to those of untreated diabetes mellitus, with the distinction that the urine is not sweet as it does not contain glucose and there is no hyperglycemia (elevated blood glucose). Blurred vision is a rarity. Signs of dehydration may also appear in some individuals since the body cannot conserve much (if any) of the water it takes in.
The extreme urination continues throughout the day and the night. In children, DI can interfere with appetite, read more [...]