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Showing posts with label Medical Instrument. Show all posts
Showing posts with label Medical Instrument. Show all posts

Monday, November 19, 2007

X-ray Machine

Researched by Alex
An X-ray machine utilizes electromagnetic radiation to produce an image of an object, usually with the purpose of visualizing something located below the object's surface. The machine is made up of an X-ray source or X-ray tube, an x-ray detection system, and positioning hardware to align these two components with the object to be imaged.

X-rays are produced by bombarding a surface with high speed electrons (in a vacuum). One of the first X-ray photographs was made of the hand of Röntgen's wife. The image displayed both her wedding ring and bones.

How they work

An X-ray imaging system consists of a X-ray source or generator, and an image detection system which can either be comprised of film (analog technology) or a digital capture system.

X-ray Sources

In the typical X-ray source of less than 450 kV, X-ray photons are produced by an electron beam striking a target. The electrons that make up the beam are emitted from a heated cathode filament. The electrons are then focused and accelerated towards an angled anode target. The point where the electron beam strikes the target is called the focal spot. Most of the kinetic energy contained in the electron beam is converted to heat, but around 10% of the energy is converted into X-ray photons, the excess heat is dissipated via a heat sink. At the focal spot, X-ray photons are emitted at 180° from the target surface, the highest intensity being around 60° to 90°, there is a small round window in the X-ray tube directly above the angled target. This window allows the X-ray to exit the tube with little attenuation while maintaining a vacuum seal required for the X-ray tube operation.

X-ray machines work by applying controlled voltage, current, and time to the X-ray tube, which results in a beam of X-rays. The beam is projected on matter. Some of the X-ray beam will pass through the object, while some are reflected. The resulting pattern of the radiation is then ultimately detected by a detection medium including rare earth screens (which surround photographic film), semiconductor detectors, or X-ray image intensifiers.

X-Ray Detection

In health care applications in particular, the x-ray detection system rarely consists of the detection medium. For example, a typical stationary radiographic x-ray machine also includes an ion chamber and grid. The ion chamber is basically a hollow plate located between the detection medium and the object being imaged. It determines the level of exposure by measuring the amount of x-rays that have passed through the electrically charged, gas-filled gap inside the plate. This allows for minimization of patient radiation exposure by both ensuring that an image is not underdeveloped to the point the exam needs to be repeated and ensuring that more radiation than needed is not applied. The grid is usually located between the ion chamber and object and consists of several lead slats stacked next to each other (resembling open window blinds). In this manner, the grid allows straight x-rays to pass through to the detection medium but absorbs reflected x-rays. This improves image quality by preventing reflected (non-diagnostic) x-rays from reaching the detection medium allowing for lower exam doses overall.

Images taken with such devices are known as X-ray photographs or radiographs. The older term Röentgenogram continues to be used by radiologists.

Medical Uses

There are two basic areas in which Health Care uses X-radiation; Radiography, and Dental Hygine.

Radiography is used for fast, highly penetrating images. Usually it's used on areas with a high bone content. Some forms of radiography uses are Panoramic X-rays, Radiography, Mammography, Tomography, and Radiotherapy.

Fluoroscopy is used in cases where real-time visualization is necessary. You may have seen a type of fluorography at the airport. Some of the uses of Fluorography are Angiography, barium enemas, barium swallows, biopsies, and hip replacement.

X-rays are highly penetrating, ionizing radiation, and X-ray machines are used in radiology to take pictures of bones and teeth. This is because bones absorb the radiation more than the less-dense soft tissue. X-rays from a source pass through the body and onto a photographic cassette. Areas where radiation is absorbed show up as lighter shades of gray (closer to white). This can be used to diagnose broken or fractured bones. Imaging of the digestive tract is done with the help of a radiocontrast agent such as barium sulfate, which is opaque to X-rays.

Source: Wikipedia

If you find an error, please let us know.

Monday, November 12, 2007

Foley Catheter

Researched by Anthony
Foley catheters are flexible (usually latex) tubes that are passed through the urethra during urinary catheterization and into the bladder to drain urine. They are retained by means of a balloon at the tip which is inflated with sterile water. The balloons typically come in two different sizes: 5 cc and 30 cc.

The relative size of a Foley catheter is described using French units (F). The most common Foley catheters typically range from 10 F - 28 F. 1 F is equivalent to 0.33 mm = .013" = 1/77" of diameter. Thus the size in French units is roughly equal to the circumference of the catheter in millimeters.

Foley catheters come in several sub-types. Coudé (French for elbowed) catheters have a 45° bend at the tip to allow easier passage through an enlarged prostate. Council tip catheters have a small hole at the tip which allows them to be passed over a wire. 3-way catheters are used primarily after bladder, prostate cancer or prostate surgery. They have a third arm or bell that allows an irrigant to pass to the tip of the catheter through a small separate channel into the bladder. This serves to wash away blood and small clots through the primary arm that drains into a collection device. This prevents larger clots, which might plug the catheter, from forming. The second, or inflation, arm has a small plastic valve that allows for the introduction or removal of sterile water through a very small channel to inflate or deflate the retaining balloon.

Foley catheters can also be used to "ripen" the cervix, to allow the induction of labor. The catheter is inserted behind the cervical wall and inflated. The remaining length of the catheter is gently pulled and taped to the inside of the woman's leg. The inflated balloon applies pressure to the cervix, like the baby's head would prior to labor, causing it to dilate. Over time the catheter is adjusted and re-taped to maintain pressure on the cervix. When the cervix has dilated sufficiently, the catheter simply drops out.

They were designed by Dr. Frederick Foley, a surgeon working in Boston, Massachusetts in the 1930s, when he was a medical student.

His original design was adopted by C. R. Bard of Murray Hill, New Jersey, who manufactured the first prototypes and named them in honor of the surgeon.

Source: Wikipedia

If you find an error, please let us know.

Wednesday, October 31, 2007

Metzenbaum Scissors

Researched by Anthony


Metzenbaum scissors are surgical scissors designed for cutting delicate tissue. The scissors come in variable lengths and have a relatively long handle-to-blade ratio. They are constructed of tungsten carbide and its blades can be curved or straight. Also, the blade tips can be either sharp or blunt.

Source: Wikipedia - the Free Encyclopedia

If you find an error, please let us know.

Thursday, October 25, 2007

Operating Scissors

Researched by Anthony
Operating scissors are general medical scissors that are available with a variety of blade styles, in various sizes and designs. An essential component of any first-aid kit, operating scissors are floor grade which means they are for regular use and they are also autoclavable, which means that they can be used for any surgical procedure. Operating scissors are very sharp blunt tip scissors. They have a screw lock. They are used in general surgery for cutting sutures, gauze and other such material. They need to be sharpened regularly.

Materials

These scissors are made of high-quality stainless steel. They are also made of other metals like chrome, aluminum etc. However, stainless steel operating scissors with sand finish are very popular.

Types of operating scissors

* Operating scissors, straight
* Operating scissors, curved
* Mayo operating scissors, straight
* Mayo operating scissors, curved

Types of blades in operating scissors

* Sharp/blunt
* Blunt/blunt
* Sharp/sharp
* Blunt/sharp

Source: http://www.surgicalsindia.com

Tuesday, October 23, 2007

Tenotomy Scissors

Researched by Anthony
Tenotomy scissors are important surgical scissors used for delicate surgery on eyelids, lips, etc, where extreme control is necessary. They are ideal for tissue dissection. They are available in different lengths and sizes, to suit various surgical procedures.

Uses of tenotomy scissors

Tenotomy scissors have both the blades sharp or blunt and they may be curved or straight. The fine tip tenotomy scissors are precision scissors that can be used in neuro-surgery, dissection and transplant around critical structures. Sharp tips in such scissors are used for fine delicate cutting whereas blunt tips for blunt dissection of delicate tissue, mucous membrane, conjunctiva. These scissors have a fine tip for fine or delicate surgical dissection.

Types of tenotomy scissors

* Straight, blunt.
* Curved, blunt.
* Straight, sharp.
* Straight, light model, blunt tips.
* Straight, large ribbon style rings.
* Straight, standard model, blunt tips.
* Curved, sharp.
* Curved, light model, blunt tips.
* Curved, ribbon style rings.
* Curved, standard model, blunt tip.

Source: http://www.surgicalsindia.com

Saturday, October 20, 2007

Stitch Scissors

Researched by Anthony
Stitch scissors are available in wide variety. They are indispensable in most operating rooms, hospitals, and doctors’ clinics. Stitch scissors are used for cutting the sutures. They are available in various lengths and their usage depend on the length of the stitch. Stitch scissors are designed to perform general to the most specific of procedures and tasks.

All stitch scissors are made of surgical stainless steel. They are autoclavable. They are designed with sharp or blunt tips and curved, hooked or blunt curved blades. The top blade of the scissor is straight and the lower one is either hooked or curved out ward. The bottom blade is blunt and can easily lift and grasp the suture to be snipped. Also known as suture scissors, they are equipped with a serrated blade for tough situations.

There are 6, 5-1/2 inch, 4-3/4 inch. 4-1/2 inch etc. straight or curved tip stitch scissors with a light pattern tip or specialized tip designs that can accommodate any procedure that requires their use. There are curved stitch scissors measuring 3-1/2 inch in length, and are available with straight, or bent tip blades. They are used to perform well in smaller spaces.

Source: http://www.surgicalsindia.com

Wednesday, October 17, 2007

Iris Scissors

Researched by Anthony
Iris scissors are designed for eye surgery and not for skin surgery and hence the name. Iris scissors are used for remove necrotic tissue. These are very sharp, pointed scissors, available with either curved or angular cutting blades. Straight scissors are for flat surfaces. They are fine, curved scissors that follow the contours of tissue in a small area. They are rather handy multipurpose scissors for cutting dressings, gauze, tape, and curved ones are especially good for cutting duoderm and ostomy wafers. They are considered to be good starting scissors for beginners in dissection. Besides being used as operating scissors, iris scissors are very useful for fine cutting in embroidery as well.

Materials

Iris scissors are made with carbon steel wire and chrome plated. These are considered to be economical scissors. The expensive ones are made with fine quality stainless steel. They are usually sand finish or mirror polished.

Types of Iris scissors

* Surgical Straight Scissors: Straight iris scissors cut along flat surfaces.
* Surgical Curved Scissors: Fine, curved iris scissors follow the contours of tissue in a small area.

Features

Iris scissors features precision ground blades which help in effortless cutting. These scissors have fine points for fine dissection work.

Source: http://www.surgicalsindia.com

Dissecting Scissors

Researched by Anthony
Dissecting scissors are widely used in hospitals and health care units for any surgical procedure. These scissors are made for fine dissection work. These scissors are available in a wide variety. Iris and tenotomy scissors are different kinds of dissecting scissors.

Types of dissecting scissors

Dissecting scissors may have curved or straight blades. The straight scissors have very sharp tips. The two sharp point blades in the dissecting scissors find great use where any dissection work is needed or in professional laboratory or in any home. The curved scissors are more preferred by the surgeons for dissecting as they provide better vision of the operated area. The tips of scissors are also used to spread and probe the area of incision. The smaller sizes are used at the surface, the larger sizes deeper in the cavities. This curved blades have tips that are rounded to avoid possible damage to structures during dissection.

Materials

Most of the dissecting scissors are made with high quality stainless steel. Some scissors are made with chrome plated steel. Most dissecting scissors have sand finish or high-grade polished stainless steel finish. Chrome plating scissors are cost effective.

Advantages of dissecting scissors

* Functionality.
* Smooth operation.
* Engineered and designed for proper tension.
* If it is too loose, there will be poor cutting.
* Correct tension, combined with blade sharpness in such scissors results in quality cutting every time.
* Quality Appearance.

Source: http://www.surgicalsindia.com

Monday, October 15, 2007

Bandage Scissors

Researched by Anthony
Bandage scissors are an important component of any first-aid kit. These scissors are angled tip scissors, with the blunt tip on the bottom blade which helps in cutting bandages without gouging the skin. Bandage scissors are very popular in any health care facility because they are designed to safely lift bandages away from skin for easy cutting. The bottom blade of the scissor is longer and goes easily under the bandages. The blunt tip design of the scissor prevents accidental injury while making bandage removal very easy, smooth and quick. The scissors safely lifts bandage away from skin for easy cutting.

Features of bandage scissors

* The blades of bandage scissors are made from stainless steel for long-lasting durability.
* Bandage scissors materials are generally ferrous materials like stainless steel materials. Nonferrous materials as well as hard metals or alloys may also be used. Therefore, the method for plating and also the plating material should be properly selected taking the scissors blade material into consideration.
* They make a useful addition to any first-aid kit.
* They can cut through cloth, plastic and metal.
* They have serrated blades for no-slip cutting.
* They are fully autoclavable.
* They are usually available with contoured handles in various colors. The handles are plastic or metal made.

Uses of bandage scissors

Bandage scissors are mostly used

* To cut through custom-fit bandages.
* To cut through medical gauze.
* To cut through bandages already in place.

Source: http://www.surgicalsindia.com