X-ray Nurse

Prostate Cancer

2006-11-05T17:21:00.000-08:00

Prostate cancer overview
Prostate cancer is the most common form of cancer in American men, most prevalent in men over age 65 and fairly common in men 50-64 years old. However, prostate cancer can occur in men younger than 50. The incidence of diagnosed prostate cancer among American men has increased dramatically from 1988 to 1992 because of the use of a screening blood test called prostate-specific antigen (PSA). More recently, men below the age of 65 years have shown an increased incidence of this disease.

What are my treatment options?
Treatment options overview
How can I choose from among the options?
If I choose surgery, will radiation treatment still be required?
How effective is modern radiation treatment of prostate cancer?
Treatment options overview
There are many treatment options for prostate cancer that is confined to the prostate gland and has not spread beyond its borders. Each option should be considered carefully, balancing the advantages against the disadvantages as they relate to the individual man's age, overall health and personal preferences.
Historical standard options include:
Surgery (radical prostatectomy) - An incision is made in the lower abdomen or through the perineum (between the anus and the scrotum), and the prostate is removed. Incomplete surgery, in which the entire tumor cannot be removed, may be followed by radiation therapy. Possible side effects of surgery can include incontinence (inability to control urination) and impotence (inability to achieve erection).
Radiation therapy (external beam therapy) - In small doses over a period of several weeks, the diseased area is exposed to highly focused energy waves that disrupt the ability of dangerous cells to grow and multiply. Treatment is painless, though some men experience diarrhea, urinary symptoms and dry skin. For more detailed information, see the External Beam Therapy page.
Watchful waiting - No treatment, with careful observation and medical monitoring.
Newer, advanced options have been developed in the past 10 to 15 years. These newer options avoid or minimize some of the unpleasant side effects sometimes associated with the standard therapies. These options include:
Nerve-sparing radical prostatectomy - Surgical procedure in which the prostate gland is removed without severing the critical nearby nerves that send signals between the brain and penis to allow normal sexual functioning. A skilled and experienced surgeon may be able to preserve sexual function in 50 percent to 90 percent of patients by successfully using this procedure.
Conformal radiation therapy - Uses advanced technology to tailor the radiation therapy to an individual's body structures. Relying on computerized three-dimensional images of the prostate, bladder, rectum and penis, the x-ray radiation beam is aimed precisely ("conformed") to affect the diseased area. In this way, less radiation reaches the surrounding normal tissues. Today there are two levels of conformal radiation therapy: 3-D conformal radiation therapy and intensity modulated radiation therapy (IMRT). Both allow for increased doses to the tumor while protecting the normal surrounding organs. IMRT is considered the more conformal of the two but is not necessary or appropriate for all patients. For more detailed information see the Intensity-Modulated Radiation Therapy page.
Proton beam therapy - A type of conformal therapy that bombards the diseased tissue with protons instead of x-rays. (Protons are part of atoms and carry a positive electric charge.) Currently, there are very few centers in the U.S. that have this type of radiation beam available for proton beam therapy. No direct comparisons have been made on the effectiveness of 3-D x-ray therapy or IMRT versus proton-based treatment.
Cryotherapy - A procedure that uses extremely low temperatures (-190°C) to freeze and destroy cancer cells. Some experienced physicians have had good results with low complication rates using cryotherapy; however, others have not. This should be considered somewhat experimental at this time as upfront treatment for prostate cancer, until there is longer follow-up for patients treated with this modality. This technique was developed as an alternative to surgery for patients who have recurrent cancer in the prostate after radiation treatments. For more detailed information, see the Cryotherapy page.
Radioactive seed implant therapy - Also called "brachytherapy," it puts radiation right where the cancer is. Tiny radioactive seeds (about the size of a grain of rice) are implanted into the prostate, where the radiation kills the cancer cells. Because the seeds are so close to the cancer cells, the cancer cells get inundated with radiation while the rectum, bladder, penis and other surrounding tissues receive much less radiation.Other radiation therapy techniques penetrate radiation from outside the body to the inside. The radiation must first go through normal tissue before it reaches the prostate located deep inside the body. With seed implant treatment, radiation hits the prostate first, and only then strikes normal tissues. While the implant technique has been around for decades, recent advances in imaging technology have made it more effective. Using ultrasound to see the prostate gland better, physicians can place each seed in the prostate more carefully and better control the effect on surrounding tissues. Long-term results are available for up to 10–12 years at some institutions. These results show that ultrasound-guided radioactive implantation by very experienced physicians is highly effective in controlling prostate cancer and has essentially the same result as surgery or external radiation for appropriately selected low-risk prostate cancer patients.
High Dose Rate (HDR) Brachytherapy - This technique was developed to supplement the dose of radiation given as external beam therapy for patients with high risk prostate cancer. In highly skilled hands, this is an effective regimen to treat such cancers. Patients receive several weeks of standard external beam radiation therapy, followed by one to three HDR sessions. These sessions require anesthesia and placement of several needles into the prostate. The patient is then hooked up to the HDR machine, where a radioactive source moves up and down each needle, delivering radiation. This type of brachytherapy leaves no permanent radiation in the patient.Use of this technique by itself (i.e., without the external beam treatments) for low-risk patients is still in the developmental stages.
How can I choose from among the options?
In addition to talking with family and friends, you will need a team of physicians to help advise you. By the time of diagnosis, you will already have met two of the three or four doctors you will need for your cancer treatment planning: your primary care physician (an internist or family practice doctor) and a urologist, who probably performed the biopsy. (In some cases, a radiologist performs the biopsy.) If you have an early-stage cancer or moderately advanced cancer and there is no evidence of spread to other organs (non-metastatic), you need to talk to one more doctor: a radiation oncologist. The two major options for treatment are surgery (performed by your urologist) and radiation therapy (performed by a radiation oncologist).
If your cancer is advanced and you require chemotherapy, then you will also need a medical oncologist, who administers chemotherapy. Hormones, which are often used to treat prostate cancer, can be administered by your internist, urologist, radiation oncologist or medical oncologist.
If I choose surgery, will radiation treatment still be required?
If your surgery is incomplete (meaning that some cancer still remains), additional radiation therapy within three to six months can prevent reoccurrence in many men. You will want to discuss this option with your physician team.
How effective is modern radiation treatment of prostate cancer?
With modern technology, radiation therapy can:
give more radiation dose directly to the prostate than to surrounding healthy tissues
help physicians use x-rays to see the prostate and surrounding tissues in three dimensions, so that the radiation beams can be tailored more precisely to the individual patient's unique needs
estimate what dose of radiation the nearby rectum, bladder, hips and penis will receive during the course of x-ray treatments to the prostate
safely provide a higher dose of radiation than even five years ago, which helps to improve the chances of cure.

What happens during radiation therapy?
Radiation is a special kind of energy carried by waves or a stream of particles. When radiation is used at high doses (many times those used for x-ray imaging exams), it can destroy abnormal cells that cause cancer and other illnesses.

What are possible side effects of radiation therapy?
As radiation treatment progresses, it may cause patients to become tired. Resting is important, but doctors usually advise patients to try to stay as active as they can. Patients may have diarrhea and/or frequent and uncomfortable urination. In addition, when patients receive external radiation therapy, it is common for the skin in the treated area to become dry. Redness or tenderness is unusual. Radiation therapy can also cause hair loss in the pelvic area. The loss may be temporary or permanent, depending on the amount of radiation used.
Radiation therapy (either external radiation or "seed" implant) causes impotence in some men. The rate of impotence is similar to patients who undergo nerve-sparing prostatectomy. There is also a slight risk that bladder or rectal problems may occur with either type of radiation. If this occurs, it usually presents itself one to three years after radiation therapy.

What kind of treatment follow-up should I expect?
Patients are usually asked to return to see the radiation oncologist about two to four weeks after the last session of radiation therapy. The main purpose of this first visit after the treatment is to see whether the side effects—such as loose bowels or urinary symptoms—have subsided. In more than 90 percent of patients, these symptoms do subside in two weeks. The doctor will check your skin and ask you to use moisturizing lotions on the dry skin. Blood will be drawn for prostate-specific antigen (PSA), a protein found in semen; an elevated level of PSA can indicate the presence of prostate cancer. A digital rectal examination will be done to feel the prostate gland, if you do not have too much discomfort in the rectal region.
Depending on the PSA level and stage of the cancer, hormones may be used in addition to radiation therapy to help control the cancer.
If you ask the radiation oncologist, "How am I doing? Is the cancer all gone? Am I cured?" he or she cannot answer these questions immediately. After radiation therapy, the response may take months to fully manifest. Dead cancer cells have to be gradually disposed of by the body. Some cancer cells, even if technically dead (i.e., they cannot multiply), may continue to function for some time before they ultimately die.

What are Obstetric Ultrasound Scans?

2006-10-10T06:28:00.000-07:00

Obstetric Ultrasound is the use of ultrasound scans in pregnancy. Since its introduction in the late 1950’s ultrasonography has become a very useful diagnostic tool in Obstetrics.
Currently used equipments are known as real-time scanners, with which a continous picture of the moving fetus can be depicted on a monitor screen. Very high frequency sound waves of between 3.5 to 7.0 megahertz (i.e. 3.5 to 7 million cycles per second) are generally used for this purpose.
They are emitted from a transducer which is placed in contact with the maternal abdomen, and is moved to "look at" (likened to a light shined from a torch) any particular content of the uterus. Repetitive arrays of ultrasound beams scan the fetus in thin slices and are reflected back onto the same transducer.
The information obtained from different reflections are recomposed back into a picture on the monitor screen (a sonogram, or ultrasonogram). Movements such as fetal heart beat and malformations in the feus can be assessed and measurements can be made accurately on the images displayed on the screen. Such measurements form the cornerstone in the assessment of gestational age, size and growth in the fetus.
A full bladder is often required for the procedure when abdominal scanning is done in early pregnency. There may be some discomfort from pressure on the full bladder. The conducting gel is non-staining but may feel slightly cold and wet. There is no sensation at all from the ultrasound waves.
A short history of the development of ultrasound in pregnancy can be found in the History pages.
Why and when is Ultrasound used in Pregnancy?
Ultrasound scan is currently considered to be a safe, non-invasive, accurate and cost-effective investigation in the fetus. It has progressively become an indispensible obstetric tool and plays an important role in the care of every pregnant woman.
The main use of ultrasonography are in the following areas:
1. Diagnosis and confirmation of early pregnancy.
The gestational sac can be visualized as early as four and a half weeks of gestation and the yolk sac at about five weeks. The embryo can be observed and measured by about five and a half weeks. Ultrasound can also very importantly confirm the site of the pregnancy is within the cavity of the uterus.
2. Vaginal bleeding in early pregnancy.
The viability of the fetus can be documented in the presence of vaginal bleeding in early pregnancy. A visible heartbeat could be seen and detectable by pulsed doppler ultrasound by about 6 weeks and is usually clearly depictable by 7 weeks. If this is observed, the probability of a continued pregnancy is better than 95 percent. Missed abortions and blighted ovum will usually give typical pictures of a deformed gestational sac and absence of fetal poles or heart beat.
Fetal heart rate tends to vary with gestational age in the very early parts of pregnancy. Normal heart rate at 6 weeks is around 90-110 beats per minute (bpm) and at 9 weeks is 140-170 bpm. At 5-8 weeks a bradycardia (less than 90 bpm) is associated with a high risk of miscarriage.
Many women do not ovulate at around day 14, so findings after a single scan should always be interpreted with caution. The diagnosis of missed abortion is usually made by serial ultrasound scans demonstrating lack of gestational development. For example, if ultrasound scan demonstrates a 7mm embryo but cannot demonstrable a clearcut heartbeat, a missed abortion may be diagnosed. In such cases, it is reasonable to repeat the ultrasound scan in 7-10 days to avoid any error.
The timing of a positive pregnancy test may also be helpful in this regard to assess the possible dates of conception. A positive pregnancy test 3 weeks previously for example, would indicate a gestational age of at least 7 weeks. Such information would be useful against the interpretation of the scans. Please read the FAQs for more comments.
In the presence of first trimester bleeding, ultrasonography is also indispensible in the early diagnosis of ectopic pregnancies and molar pregnancies.
3. Determination of gestational age and assessment of fetal size.
Fetal body measurements reflect the gestational age of the fetus. This is particularly true in early gestation. In patients with uncertain last menstrual periods, such measurements must be made as early as possible in pregnancy to arrive at a correct dating for the patient. See FAQ. In the latter part of pregnancy measuring body parameters will allow assessment of the size and growth of the fetus and will greatly assist in the diagnosis and management of intrauterine growth retardation (IUGR).
The following measurements are usually made:
a) The Crown-rump length (CRL)
This measurement can be made between 7 to 13 weeks and gives very accurate estimation of the gestational age. Dating with the CRL can be within 3-4 days of the last menstrual period. (Table) An important point to note is that when the due date has been set by an accurately measured CRL, it should not be changed by a subsequent scan. For example, if another scan done 6 or 8 weeks later says that one should have a new due date which is further away, one should not normally change the date but should rather interpret the finding as that the baby is not growing at the expected rate.
b) The Biparietal diameter (BPD)
The diameter between the 2 sides of the head. This is measured after 13 weeks. It increases from about 2.4 cm at 13 weeks to about 9.5 cm at term. Different babies of the same weight can have different head size, therefore dating in the later part of pregnancy is generally considered unreliable. (Chart and further comments) Dating using the BPD should be done as early as is feasible.
c) The Femur length (FL)
Measures the longest bone in the body and reflects the longitudinal growth of the fetus. Its usefulness is similar to the BPD. It increases from about 1.5 cm at 14 weeks to about 7.8 cm at term. (Chart and further comments) Similar to the BPD, dating using the FL should be done as early as is feasible.
d) The Abdominal circumference (AC)
The single most important measurement to make in late pregnancy. It reflects more of fetal size and weight rather than age. Serial measurements are useful in monitoring growth of the fetus. (Chart and further comments) AC measurements should not be used for dating a fetus.
Other important measurements are discussed here.
The weight of the fetus at any gestation can also be estimated with great accuracy using polynomial equations containing the BPD, FL, and AC. computer softwares and lookup charts are readily available. For example, a BPD of 9.0 cm and an AC of 30.0 cm will give a weight estimate of 2.85 kg. (comments)
4. Diagnosis of fetal malformation.
Many structural abnormalities in the fetus can be reliably diagnosed by an ultrasound scan, and these can usually be made before 20 weeks. Common examples include hydrocephalus, anencephaly, myelomeningocoele, achondroplasia and other dwarfism, spina bifida, exomphalos, Gastroschisis, duodenal atresia and fetal hydrops. With more recent equipment, conditions such as cleft lips/ palate and congenital cardiac abnormalities are more readily diagnosed and at an earlier gestational age. (Also see the FAQ and Anomalies pages).
First trimester ultrasonic 'soft' markers for chromosomal abnormalities such as the absence of fetal nasal bone, an increased fetal nuchal translucency (the area at the back of the neck) are now in common use to enable detection of Down syndrome fetuses.
Read also: Soft Markers - A Guide for Professionals and Ultrasonographic "soft markers" of fetal chromosomal defects.
Ultrasound can also assist in other diagnostic procedures in prenatal diagnosis such as amniocentesis, chorionic villus sampling, cordocentesis (percutaneous umbilical blood sampling) and in fetal therapy.
5. Placental localization.
Ultrasonography has become indispensible in the localization of the site of the placenta and determining its lower edges, thus making a diagnosis or an exclusion of placenta previa. Other placental abnormalities in conditions such as diabetes, fetal hydrops, Rh isoimmunization and severe intrauterine growth retardation can also be assessed.
6. Multiple pregnancies.
In this situation, ultrasonography is invaluable in determining the number of fetuses, the chorionicity, fetal presentations, evidence of growth retardation and fetal anomaly, the presence of placenta previa, and any suggestion of twin-to-twin transfusion.
7. Hydramnios and Oligohydramnios.
Excessive or decreased amount of liquor (amniotic fluid) can be clearly depicted by ultrasound. Both of these conditions can have adverse effects on the fetus. In both these situations, careful ultrasound examination should be made to exclude intraulterine growth retardation and congenital malformation in the fetus such as intestinal atresia, hydrops fetalis or renal dysplasia. See also FAQ and comments.
8. Other areas.
Ultrasonography is of great value in other obstetric conditions such as:
a) confirmation of intrauterine death. b) confirmation of fetal presentation in uncertain cases.c) evaluating fetal movements, tone and breathing in the Biophysical Profile.d) diagnosis of uterine and pelvic abnormalities during pregnancy e.g. fibromyomata and ovarian cyst.

xray2000 Nicks Website

2006-10-01T14:14:00.000-07:00

xray2000 Nicks Website

Magnetic Resonance Imaging (MRI) of the Prostate

2006-09-16T10:01:00.000-07:00

What is Magnetic Resonance Imaging (MRI) of the Prostate?
Magnetic resonance imaging (MRI) is a noninvasive way of viewing organs, soft tissues, bone and other internal body structures without the use of x-rays. MRI uses a magnetic field and radio waves together with a computer to create cross-sectional pictures of various parts of the body. Detailed MR images allow physicians to better evaluate parts of the body that may not be visible with other imaging methods such as x-ray, ultrasound or computed tomography (also called CT or CAT scan). MRI has proven valuable in diagnosing a broad range of conditions, including cancer, heart and vascular disease, stroke, and joint and musculoskeletal disorders.
The prostate is a walnut-size gland that is part of the male reproductive system. It is located below the bladder, where urine is stored, and surrounds the urethra, the tube that carries urine and other fluids out of the body. The prostate helps make the milky fluid called semen that carries sperm out of the body when a man ejaculates. Ultrasound and MRI are the most commonly used techniques to image the prostate gland.

What are some common uses of the procedure?
The three most common prostate problems are:
Infection (prostatitis)
Enlarged prostate, called benign prostatic hyperplasia (BPH)
Prostate cancer
The prostate tends to grow bigger with age due to the development of BPH. A tumor or infection can also enlarge the prostate. All of these conditions may squeeze the urethra, causing urinary problems.
Diagnosing a prostate problem may require a series of tests including an MRI exam, which can help identify abnormalities. If a biopsy has confirmed cancer, a doctor may use MRI or other imaging techniques to determine if the cancer is confined to the prostate, or if it has spread outside the walls of the prostate gland and elsewhere in the body.

How should I prepare for the procedure?
Your MRI exam may involve the use of an endorectal coil, a thin wire covered with a balloon, placed inside the rectum. This coil helps focus on the prostate and surrounding structures; it also enables your radiologist to perform magnetic resonance (MR) spectroscopy, which provides additional information on the chemicals present in the body's cells.
To prepare for an MRI with the endorectal coil, you should eat light meals on the day prior to and on the day of your exam. This will help make it easier to insert the coil. You may also be asked to use an enema preparation prior to your exam. An enema involves injecting liquid into your large intestine through your rectum to help clear the bowel.
Prior to your exam, you may continue to take your usual medications, unless you are told otherwise. You may be given a hospital gown to wear during the exam, or you may be allowed to wear your own clothing if it is loose-fitting and has no metal fasteners.
Jewelry and other accessories should be left at home if possible, or removed prior to the MRI exam. Metal and electronic objects can interfere with the MRI's magnetic field and are not allowed in the exam room. These items include:
Jewelry, watches, credit cards and hearing aids, all of which can be damaged
Pins, hairpins, metal zippers and similar metallic items, which can distort MR images
Removable dental work
Pens, pocketknives, keys, coins and eyeglasses
In most cases, an MRI exam is safe for patients with metal implants, except for a few types. Tell the technologist if you have medical or electronic devices in your body, such as:
Artificial heart valves
Implanted drug infusion ports
Implanted electronic devices, including a pacemaker
Artificial limbs or metallic joint prostheses
Implanted nerve stimulators
Metal pins, screws, plates or surgical staples
In general, metal objects used in orthopedic surgery pose no risk during MRI. However, a recently placed artificial joint may require the use of another imaging procedure. If there is any question, an x-ray may be taken to detect the presence of any metal objects. Sheet metal workers and others who might have metal objects such as shrapnel in their bodies may also require an x-ray prior to an MRI. Dyes used in tattoos may contain iron and could heat up during MRI, but this is rarely a problem.
People with the following implants cannot be scanned and should not enter the MRI area:
Cardiac pacemakers
Defibrillators
Cochlear (ear) implants
Clips used on brain aneurysms
Some MRI procedures use oral or injected contrast material to help obtain clearer images. For this reason, the radiologist or technologist will ask if you have an allergy of any kind such as hay fever, hives, allergic asthma, or allergy to food or drugs. However, the contrast material used for an MRI exam, called gadolinium, does not contain iodine and is less likely to cause an allergic reaction.
The radiologist should also know if you have any serious health problems. Some conditions, such as kidney disease and sickle cell anemia, may prevent you from having an MRI with contrast material.

What does the equipment look like?
The traditional MRI unit is a large cylinder-shaped tube surrounded by a circular magnet. The patient lies on a moveable bed that slides into the magnet so the imaging can be performed.
Other MRI units are open on all sides. These open units are especially helpful for examining patients who are claustrophobic and those who are very obese, but they may not provide the same image quality.

How does the procedure work?
Unlike conventional x-ray examinations and computed tomography (CT) scans, MRI does not depend on ionizing radiation. Instead, radio waves are directed at protons, the nuclei of hydrogen atoms, in a strong magnetic field.
The strong magnetic field is produced by passing an electric current through wire coils in the MRI unit. Other coils send and receive radio waves. As you lie in the MRI machine, radio waves are directed at the protons in your body. In the magnetic field, protons change their position, producing signals that are detected by coils within the MRI unit or placed around the body part being examined.
A computer processes these signals and generates a three-dimensional representation of your body. The radiologist can then view any two-dimensional plane (slice) from any direction on a video monitor for evaluation.
Because protons are most abundant in water molecules (the "H" in H20), MR images show differences in water content between various body tissues. As a result, MRI is especially suited to detecting disorders that increase fluid in the body, such as tumors, infection and inflammation.

How is the procedure performed?
If an endorectal coil is to be used in your MRI exam, a nurse or physician will insert the wire coil, which is enclosed within a small, flexible plastic tube, into your rectum. Once inserted, a balloon is inflated to hold the coil in place during the exam. When your exam in complete, the balloon is deflated and the coil is removed.
You will lie on your back on a narrow table that can be moved into and out of the MRI tunnel. Cushions are used to maintain the proper position of your body and to make you as comfortable as possible.
The radiologist and technologist will leave the room while the MRI examination is performed. An MRI exam generally takes 15 to 45 minutes, although only a fraction of that time is needed for the actual imaging. Imaging will be done in sequences, each lasting between a few seconds and a few minutes. During imaging, you will be instructed not to move. You will know when images are being recorded because you will hear tapping or thumping sounds when the coils that create the magnetic field are turned on. In between sequences, you will be able to relax.
If a contrast material is used to enhance the visibility of certain tissues or blood vessels, it may be injected into your arm through an intravenous (IV) line.
MR spectroscopy, which provides additional information on the chemicals present in the body's cells, may also be performed during the MRI exam and will add approximately 15 minutes to the exam time.
When your exam is completed, you will wait a short time on the table while the images are examined to ensure no additional images are needed.

What will I experience during the procedure?
MRI of the prostate is a pain-free procedure. During the exam, your prostate may feel slightly warm, but this is normal and harmless. If contrast material is injected, you may feel coolness for a minute or two.
If an endorectal coil is used, you will feel pressure in your rectum similar to that experienced during a digital rectal exam.
It is important to remain perfectly still when images are being recorded. Some patients can find it uncomfortable to remain still during MR imaging. People who tend to be nervous when in a confined space (claustrophobic) may become uncomfortable when examined in an enclosed MRI unit. Fewer than one in twenty patients will need a sedative to relieve their anxiety and help them lie still. Another option is to use an open MRI unit, if available, which is less confining than a conventional unit.
MRI scanners are air-conditioned and well-lit. During your exam, you will be able to talk to the radiologist and technologist, who will observe you from an adjacent room throughout the exam. You may request earplugs to reduce the thumping and humming noises of the MRI scanner. Some scanners have music or a built-in television to help pass the time. Many MRI centers allow a relative or friend to stay close by during your exam.
If you have not been sedated, no recovery period will be necessary. You may resume your usual activities and normal diet immediately after the exam.

Who interprets the results and how do I get them?
A radiologist, a physician experienced in MRI and other radiology examinations, will analyze the images and provide a report to your primary care or referring physician. You will most often receive your results from your primary care physician.

What are the benefits vs. risks?
Benefits
MRI is a totally noninvasive imaging technique that does not require exposure to ionizing radiation.
MRI provides more clear and detailed images of the soft-tissue structures of the body than other imaging methods. The detail makes MRI an invaluable tool in early diagnosis and evaluation of tumors.
MR images can help physicians evaluate the function as well as the structure of many organs.
MRI contrast material is less likely to produce an allergic reaction than the iodine-based materials used for conventional x-rays and CT scanning.
Risks
The MRI examination poses no risk to the average patient when appropriate safety guidelines are followed.
An undetected metal implant may be affected by the strong magnetic field.
There is a very slight risk of an allergic reaction if contrast material is injected. Such reactions usually are mild and easily controlled by medication. There also is a very small risk of skin infection at the site of injection.
If sedation is used, there are risks of excessive sedation. The technologist monitors the patient's vital signs to minimize this risk.

What are the limitations of MRI of the Prostate?
Patients who are claustrophobic may have to be sedated during an MRI exam or examined in one of the newer open MRI units. A person who is very obese may not fit into the opening of a conventional MRI machine.
The presence of an implant or other metallic object often makes it difficult to obtain clear images, and patient movement can have the same effect. A patient with severe pain may not be able to lie still during imaging.
MRI may not always distinguish between tumor tissue and edema fluid. It cannot detect calcium present in a tumor.
The MRI findings by themselves do not establish an absolute diagnosis, but in most situations the findings will suggest the correct diagnosis. The images must be interpreted along with the patient's history, physical findings, and information from other tests.
MRI may be more costly than other imaging methods including CT scanning.

finding NeMo

2006-09-01T11:22:00.000-07:00

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What iz eX rAy

2006-08-31T10:59:00.000-07:00

X-rays are a form of electromagnetic radiation with a wavelength approximately in the range of 0.5 pm - 10 nm (corresponding to frequencies in the range 30 PHz - 600 EHz).
X-rays with a wavelength longer than 0.1 nm are called soft X-rays. At wavelengths shorter than this, they are called hard X-rays. Hard X-rays overlap the range of long-wavlength (low energy) gamma rays, however the distinction between the two terms refers to the source of the radiation, not its wavelength: X-ray photons are generated by energetic electron processes, gamma rays by transitions within atomic nuclei.
History
X-rays were first observed and documented in 1895 by Wilhelm Conrad Roentgen, a German scientist who found them quite by accident when experimenting with vacuum tubes. A week later, he took an X-ray photograph of his wife's hand which clearly revealed her wedding ring and her bones. The photograph electrified the general public and aroused great scientific interest in the new form of radiation. Roentgen called it "X" to indicate it was an unknown type of radiation. The name stuck, although (over Roentgen's objections), many of his colleagues suggested calling them Roentgen rays. They are still occasionally referred to as Roentgen rays in German-speaking countries.
Uses:
X-rays are highly penetrating of many materials, and are used in medicine 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 are passed through the body and onto a photographic plate; areas where radiation is absorbed show up as white and can be used to show broken or fractured bones.
Exposure to x-ray radiation is dangerous and cancer causing, so radiographers try to keep exposure to the patient to a mimimum. Radiographers themselves wear lead aprons or stay behind a lead screen.
Diffraction of X-rays in chemistry can be used to investigate the structures of crystals and other structures - x-ray crystallography.
X-ray Astronomy is the study of the universe by analyzing the x-ray radiation which we receive on the earth.
Some lasers rely on x-rays.
fRom : WikiPedia

Nursing in Xray is Suck !!! lolz

2006-08-21T04:30:00.000-07:00

hahahha..let say anything about xray and nursing Lolz