An intraocular lens (IOL) is an implanted lens in the eye, usually replacing the existing crystalline lens because it has been clouded over by a cataract, or as a form of refractive surgery to change the eye's optical power. It usually consists of a small plastic lens with plastic side struts, called haptics, to hold the lens in place within the capsular bag inside the eye.[citation needed] IOLs were traditionally made of an inflexible material (PMMA), although this has largely been superseded by the use of flexible materials. Most IOLs fitted today are fixed monofocal lenses matched to distance vision. However, other types are available, such as multifocal IOLs which provide the patient with multiple-focused vision at far and reading distance, and adaptive IOLs which provide the patient with limited visual accommodation.

In United States safety standards, precautionary statements are sentences providing information on potential hazards, and proper procedures. They are used in situations from consumer product on labels and manuals, to descriptions of physical activities. Various methods are used to bring focus to them, such as setting apart from normal text, graphic icons, changes in text's font and color. Texts will often clarify the types of statements and their meanings within the text. Common precautionary statements are described below.

Dose means quantity in the following fields: In nutrition, medicine, and toxicology: * Dose (biochemistry), the quantity of something that may be eaten by or administered to an organism, or that an organism may be exposed to In medicine and toxicology: * Absorbed dose, an amount of radiation received * Dosing, the process of administering a measured amount of a medicine or chemical to an inanimate object or non-human animal * Effective dose, the smallest amount of a substance required to produce a measurable effect on a living organism * Equivalent dose, a measure of radiation dosage to tissue * Maximum tolerated dose, the highest dose of a radiological or pharmacological treatment that will produce the desired effect without unacceptable toxicity. * Optimal Biological Dose, the quantity of a radiological or pharmacological treatment that will produce the desired effect with acceptable toxicity. * Reference dose, the United States Environmental Protection Agency's maximum acceptable oral dose of a toxic substance Dosage is a synonym for the biochemical term dose!

In medicine, most medications can be safely used with other medicines, but particular combinations of medicines need to be monitored for interactions, often by the pharmacist. In molecular biology, the knowledge on gene/protein interaction among themselves and with their metabolites is referred to as molecular pathways. Interactions between medications (drug interactions) fall generally into one of two main categories: 1. pharmacodynamic : Involving the actions of the two interacting drugs. 2. pharmacokinetic : Involving the absorption, distribution, metabolism, and excretion of one or both of the interacting drugs upon the other. In terms of efficacy, there can be three types of interactions between medications: additive, synergistic, and antagonistic. Additive interaction means the effect of two chemicals is equal to the sum of the effect of the two chemicals taken separately. This is usually due to the two chemicals acting on the body in the same way. Examples would be Aspirin and Motrin, Alcohol and Depressant, Tranquilizer and Painkiller. Synergistic interaction means that the effect of two chemicals taken together is greater than the sum of their separate effect at the same doses. An example is Pesticide and Fertilizer, the biological effect is devastating. Antagonistic interaction means that the effect of two chemicals is actually less than the sum of the effect of the two drugs taken independently of each other. This is because the second chemical increases the excretion of the first, or even directly blocks its toxic actions. Antagonism forms the basis for antidotes of poisonings.

In medicine, an adverse effect is a harmful and undesired effect resulting from a medication or other intervention such as surgery. An adverse effect may be termed a "side effect", when judged to be secondary to a main or therapeutic effect, and may result from an unsuitable or incorrect dosage or procedure, which could be due to medical error. Adverse effects are sometimes referred to as "iatrogenic" because they are generated by a physician/treatment. Some adverse effects only occur only when starting, increasing or discontinuing a treatment. Using a drug or other medical intervention which is contraindicated may increase the risk of adverse effects. Adverse effects may cause medical complications of a disease or procedure and negatively affect its prognosis. They may also lead to non-compliance with a treatment regimen. The harmful outcome is usually indicated by some result such as morbidity, mortality, alteration in body weight, levels of enzymes, loss of function, or as a pathological change detected at the microscopic, macroscopic or physiological level. It may also be indicated by symptoms reported by a patient. Adverse effects may cause a reversible or irreversible change, including an increase or decrease in the susceptibility of the individual to other chemicals, foods, or procedures, such as drug interactions. In clinical trials, a distinction is made between adverse events (AEs) and serious adverse events (SAEs). Generally, any event which causes death, permanent damage, birth defects, or requires hospitalization is considered an SAE.[1] The results of these trials are often included in the labeling of the medication to provide information both for patients and the prescribing physicians.

complications that may arise following surgery

intraoperative complications, are complications, problems within operation, intraoperative problems.

Complication, in medicine, is an unfavorable evolution of a disease, a health condition or a medical treatment. The disease can become worse in its severity or show a higher number of signs, symptoms or new pathological changes, become widespread throughout the body or affect other organ systems. A medical treatment, such as drugs or surgery may produce adverse effects and/or produce new health problem(s) by itself. A new disease may also appear as a complication to a previous existing disease. Therefore, a complication may be iatrogenic, i.e., literally brought forth by the physician. Medical knowledge about a disease, procedure or treatment usually entails a list of the most common complications, so that they can be foreseen, prevented or recognized more easily and speedily. Depending on the degree of vulnerability, susceptibility, age, health status, immune system condition, etc. complications may arise more easily. Complications affect adversely the prognosis of a disease. Non-invasive and minimally invasive medical procedures usually favor fewer complications in comparison to invasive ones. Examples of complications * Generalized septicemia (infection of the blood) may occur as a complication of an infected wound or abscess * Allergic shock can be a reaction to several kinds of anesthetics, as a complication in a surgery * Fractured ribs and sternum may be a complication of cardiopulmonary resuscitation attempts in people suffering severe osteoporosis * Puerperal fever may be a common complication of childbirth and used to kill a large proportion of mothers before the advent of antisepsis and antibiotics * Diabetes mellitus may present a series of complications in an advanced or more severe stage, such as gangrene, diabetic foot, blindness, infections, etc. * Thrombosis in the heart or brain, causing stroke or acute myocardial infarction can be complications of blood coagulation disorders, phlebitis (inflammation of the veins), endocarditis and artificial heart valves * Eczema vaccinatum is a rare and severe complication of smallpox vaccination in people with eczema * Hepatotoxic dementia is a possible complication of hepatitis and liver cirrhosis * Mental retardation is a common complication of untreated hydrocephalus * A paradoxical reaction to a drug; that is, a reaction that is the opposite to the intended purpose of the drug. An example is benzodiazepines, a class of psychoactive drugs considered minor tranquilizers with varying hypnotic, sedative, anxiolytic, anticonvulsant, and muscle relaxant effects; paradoxically they may also create hyperactivity, anxiety, convulsions etc. in susceptible individuals. [1] * Erectile dysfunction and urinary incontinence are prevalent to prostatectomy.

A contraindication (pronounced as contra-indication) is a condition or factor that speaks against a certain measure. It is mostly used in medicine, with regard to factors that increase the risks involved in using a particular drug, carrying out a medical procedure, or engaging in a particular activity. Some contraindications are absolute, meaning that there are no reasonable circumstances for undertaking a course of action. For example, a baby with a fever should never be given aspirin because of the risk of Reye's syndrome, and a person with an anaphylactic food allergy should never eat the food to which they are allergic. Similarly, a person with hemochromatosis should not be administered iron preparations. Other contraindications are relative, meaning that the patient is at higher risk of complications, but that these risks may be outweighed by other considerations or mitigated by other measures. For example, a pregnant woman should normally avoid getting X-rays, but the risk may be far less than the risk of not diagnosing or being able to treat a serious condition such as tuberculosis or a broken bone. Relative contraindications may also be referred to as cautions, such as in the British National Formulary.

In medicine, an indication is a valid reason to use a certain test, medication, procedure, or surgery. The opposite of indication is contraindication.

Packaging is the science, art and technology of enclosing or protecting products for distribution, storage, sale, and use. Packaging also refers to the process of design, evaluation, and production of packages. Packaging can be described as a coordinated system of preparing goods for transport, warehousing, logistics, sale, and end use. Packaging contains, protects, preserves, transports, informs, and sells.[1] In many countries it is fully integrated into government, business, institutional, industrial, and personal use.

description a statement presenting something in words, from verb describe

"a manual usually accompanying a technical device and explaining how to install or operate it" Essential Requirements - Medical Device Directive 93/42/EEC - Annex I, 13.1: Each device must be accompanied by the information needed to use it safely and to identify the manufacturer, taking account of the training and knowledge of the potential user. This information comprises the details on the label and the data in the instructions for use. As far as practicable and appropriate, the information needed to use the device safely must be set out on the device itself and/or on the packaging of each unit. If not practicable, the information must be set out in the leaflet supplied with one or more devices. Instructions for use must be included in the packaging for every device. By way of exception, no such instruction leaflet is needed for devices in Class I or Class IIa if they can be used completely safely without any such instructions.