Visual impairment, also known as vision impairment, is a medical definition primarily measured based on an individuals better eye visual acuity; in the absence of treatment such as correctable eyewear, assistive devices, and medical treatment– visual impairment may cause the individual difficulties with normal daily tasks including reading and walking. Low vision is a functional definition of visual impairment that is chronic, uncorrectable with treatment or correctable lenses, and impacts daily living. As such low vision can be used as a disability metric and varies based on an individuals experience, environmental demands, accommodations, and access to services. The American Academy of Ophthalmology defines visual impairment as the best-corrected visual acuity of less than 20/40 in the better eye, and the World Health Organization defines it as a presenting acuity of less than 6/12 in the better eye. The term blindness is used for complete or nearly complete vision loss. In addition to the various permanent conditions, fleeting temporary vision impairment, amaurosis fugax, may occur, and may indicate serious medical problems. The most common causes of visual impairment globally are uncorrected refractive errors (43%), cataracts (33%), and glaucoma (2%). Refractive errors include near-sightedness, far-sightedness, presbyopia, and astigmatism. Cataracts are the most common cause of blindness. Other disorders that may cause visual problems include age-related macular degeneration, diabetic retinopathy, corneal clouding, childhood blindness, and a number of infections. Visual impairment can also be caused by problems in the brain due to stroke, premature birth, or trauma, among others. These cases are known as cortical visual impairment.
Isolated cases of gallstone formation have been associated with use of lanreotide, particularly over long periods of time. Pharmacology
Lanreotide is a synthetic analogue of somatostatin, a naturally occurring inhibitory hormone which blocks the release of several other hormones, including growth hormone, thyroid-stimulating hormone (TSH), insulin and glucagon. Lanreotide binds to the same receptors as somatostatin, although with higher affinity to peripheral receptors, and has similar activity. However, while somatostatin is quickly broken down in the body (within minutes), lanreotide has a much longer half-life, and produces far more prolonged effects. Formulations
Lanreotide is available in two formulations: a sustained release formulation (sold under the trade name Somatuline LA), which is injected intramuscularly every ten or fourteen days, and an extended release formulation (UK trade name Somatuline Autogel, or Somatuline Depot in the US), which is administered subcutaneously once a month. Self-assembling properties
Lanreotide has been shown to spontaneously self-assemble into monodisperse nanotubes of 24.4 nm diameter and has been thereafter used as a fruitful and versatile model system in several biophysical studies. References
External links
"Lanreotide". Drug Information Portal. U.S. National Library of Medicine.