The purpose of fluorescein angiography is to detect changes in the blood vessels of the retina. It is based on the behavior of intravenously administered sodium fluorescein in the tissues of the ocular fundus. A fluorescein dye is either taken orally or injected into the bloodstream. When the dye reaches the blood vessels of the eye, special ultraviolet lights enable the physician to photograph the vessels for later study. Any swelling or leakage of the vessels of the retina is apparent on the photograph.

Fixation forceps is used to fix the eyeball by holding the conjunctiva and episcleral tissue close to the limbus. It is necessary for inspection of the conjunctiva, including the nictitating membrane.

Foreign body forceps are slender in construction, bulb-pointed and shaped so as to be readily admitted into the trachea through a tracheal incision.

Farnsworth panel D-15 is a simple instrument to detect high-risk melanoma patients in melanoma aftercare. The Farnsworth panel D 15 test is a color test, which is able to detect all kinds of color deficiencies.

Freer periosteal elevators are used to reflect soft tissue away from the bone. The elevators are usually double ended, with one long, tapered end and one round, bladed end. It lifts gingival and mucosa from the bone overlying the buccal aspect of the canine root.

Fluorescent microscope works on the principle that an object is emitting light. It is designed to collect an optimal signal while minimizing background illumination. Two types of illumination exist for fluorescence microscopy: transmitted illumination and incident illumination. Most fluorescent microscopes use epifluorescence, meaning that the excitatory light is transmitted through the objectives onto the specimen and not through the specimen.

Fluoroscopy systems consist of a X-ray tube which produces X-rays, an image intensifier (I-I) that captures or stops the X-rays and converts the X-ray energy into light and a closed-circuit video system which ultimately produces a live image on a monitor. On some systems the light output can also be distributed to a spot film or cinematography recording systems, though the X-ray output must be greater for these imaging modalities.

Femoral components are used to replace the medial condyle and patellofemoral regions of a femoral knee joint. It is used for those patients whereby conditions exist that cannot be solely addressed by a device that treats a single compartment (i.e. unicondylar or patellofemoral prosthesis) of the knee.

Follicle stimulating hormone (FSH) is a glycoprotein gonadotropin secreted by the anterior pituitary in response to gonadotropin-releasing hormone (GnRH), which is released by the hypothalamus. In women, FSH helps control the menstrual cycle and the production of eggs by the ovaries. A FSH test measures the amount of follicle stimulating hormone in a blood sample. This test is used to evaluate to woman's egg supply (ovarian reserve) and man's low sperm count. It is done to determine whether a child is going through early puberty.

Free estriol (E3) is the principal estrogen produced during pregnancy. It is produced by the placenta from dehydroepiandosterone sulfate derived from the fetal liver and adrenals. The test is used as part of the triple marker screen (in association with alpha fetoprotein and chorionic gonadotropin) for Down syndrome.

Free T3 is an important hormone in the regulation of metabolism. Free T3 test measures the amount of T3 hormone in the blood. It is measured as part of a thyroid function evaluation. Most of the thyroid hormone made in the thyroid is in the form of T4. The body's cells convert the T4 to T3, which is the more active hormone. It is the most powerful thyroid hormone, and affects almost every process in the body, including body temperature, growth, and heart rate.

Free T4 is used as a biochemical indicator of thyroid function, and aids the diagnosis and monitoring of both hyperthyroidism and hypothyroidism. It is an amine hormone synthesized and secreted by the thyroid gland and a precursor to triiodothyronine. It is metabolically active form of the hormone.

Flap smoother is a topical, noninvasive compression procedure, that helps in eliminating what is believed to be microscopic striae or fluid accumulation that lingers once the flap is replaced following laser in situ keratomileusis. It usually has a 5mm button, angled 30 degrees from the handle. The button is placed centrally, compressing the cornea, then a squeegee motion outward is used to gently massage irregularities out of the flap immediately after surgery. This flap smoother is also ideal for dealing with irregular astigmatism problems secondary to laser in situ keratomileusis. It provides the surgeon with another option other than lifting the flap and re-treating the patient, up to 6 months post-operatively.

Fluid management systems are designed to accurately measure all inputs and outputs of fluids used. These systems are used frequently when performing operative hysteroscopy or with use of high viscosity liquid media. The basic principle of all fluid management systems consists of monitoring the amount of fluid used and monitoring the amount of fluid that is collected after the fluid passes through the uterus. It has collection bags that collect the used and spilled fluid.

Finger Clip Electrodes are constructed of solid, surgical-grade stainless steel and come with color-coded handles and ultra-flexible, red & black twisted pair leads. Finger clip electrodes have a 24″ PVC insulated leadwire or a 36″ PVC insulated shielded leadwire ending with a standard touch proof connector.

Femoral compression system is designed for hemostasis management. It provides a comfortable and efficient method of compressing the femoral artery and vein after diagnostic and interventional procedures.