Virtual Colonoscopy

Virtual Colonoscopy is a new method that permits doctors to look at the bowel (colon) to detect polyps and cancers. Polyps are small abnormal growths in the colon that can become cancerous if they are not removed. Virtual Colonoscopy is a recently developed method that uses a CT scanner and computer virtual reality software to examine inside the body without having to insert a long tube (Conventional Colonoscopy) into the colon or without having to fill the colon with liquid barium (Barium Enema).

• Procedure
  

While preparations for virtual colonoscopy, the patient will usually be asked to take laxatives or other oral agents at home the day before the procedure to clear the colon.

VC is done in the radiology department of medical center. The examination takes place within 10 minutes and does not require sedatives. During the procedure,

• The patient is placed in a supine position on the table
• A thin tube is inserted into the rectum, so that air can be pumped through the tube in order to inflate the colon for better vision.
• The table moves into the scanner to produce a series of two-dimensional cross-sections along the length of the colon. A computer puts these images together to create a three-dimensional picture that can be viewed on the screen.
• The patient is told to hold his/her breath during the scan to avoid distortion on the images.
• The scan is then repeated with the patient in a prone position.

After the examination, the images produced by the scanner must be converted into a 3D image. A radiologist sorts the results to identify any disorder.

The patient may get back to normal activity after the procedure, but if abnormalities are found and the patient needs conventional colonoscopy.

• Advantages
  

VC is comfortable than conventional colonoscopy for some patients because there is no use of a colonoscope. Consequently, no sedation is needed, and the patient can return to his/her usual activities or go home after the procedure without any aid. VC provides more detailed images than an x-ray using a barium enema, sometimes called a lower gastrointestinal (GI) series. Also it takes less time than either a conventional colonoscopy.

• Disadvantages

The main disadvantage to VC is cost. Another disadvantage is that a radiologist cannot take tissue samples or remove polyps during this process, so a conventional colonoscopy must be performed if lesions are found. In addition, VC does not show as much detail as a conventional colonoscopy, so cancerous cells smaller than 2 millimeters in diameter may not show up on the images. Virtual Colonoscopy done with CT exposes the patient to ionizing radiation; however some research has demonstrated that low dose VC can also be as effective in demonstrating colon and bowel disease due to the great difference in x-ray absorption between air and the tissue making the inner wall of the colon.

• People who should be screened for colorectal cancer
  
  Currently, it's suggested that people of 50 years and older should be screened for colorectal cancer. If there's a tendency towards colon cancer in the family, it's advised to start 10 years earlier than 50 and to use a more sensitive and specific technique. But for the general population, this limit is 50 years and older.

• People over the age of 50 who get screened by this processes
  
  The unfortunate thing is colorectal cancer should largely be a preventable illness, but in the United States at this time only 30 to 40 percent of people who ought to be screened have actually been screened. That gives us a lot of foundations to make up.

• Available screening methods for detection of colon cancer
  
  While there is always new for technological improvements, we need to improve the current screening technologies. Despite their drawbacks, they have been proven effective in reducing the burden of disease. There are five regimens that are currently suggested, providing practitioners and patients with a menu of options. They include annual fecal occult blood testing (FOBT) - that is, looking for blood in the stool; sigmoidoscopy every five years; colonoscopy every 10 years; air-contrast barium enema every five years; and a combination of FOBT with flexible sigmoidoscopy, each at their usual intervals.

Each of these tests have various advantages and disadvantages; for instance, they differ in sensitivity and specificity -- that is, how well they detect colon cancer or polyps when they're present and reassure us when they're absent. Colon cancer is the end-result of a prolonged process during which changes in genes in the cells lining the intestine accumulate, resulting in abnormal growth of cells. If polyps gather additional genetic changes, a part of them may become cancerous. We are worry about polyps becoming cancerous as they grow; for instance, polyps greater than one centimeter in diameter are usually removed because they present a high cancer risk.

• Reasons that prevent people to be screened
  
  There are many reasons why people aren't screened. Many people don’t recognize whether they should be screened or not. Do they know the current screening guidelines? If not, has colorectal cancer screening been recommended to them by their health care centers? Unfortunately, some recent surveys suggest that colorectal cancer screening is not usually recommended by health care centers, despite evidence of its benefit. Luckily, colon cancer screening and colonoscopy is now paid by Medicare, so cost is not as big a deal as it has been in the past.

• Optical colonoscopy considered the "gold standard" for colorectal cancer screening
  
  Colonoscopy is taken as the gold standard for colorectal cancer screening by some groups but not by others. Some radiologists recommend colonoscopy as a preferred approach to colorectal screening. However, optical colonoscopy is considered the gold standard by some professionals because it permits complete visualization of the entire colon, hence providing the opportunity to identify precancerous polyps and cancer, and then to do diagnostic biopsies or therapeutic removal of these lesions, as soon as possible.

Cancer?

Cancer is a Latin word meaning crab or creeping ulcer.

The human body consists of about 3 trillion cells, the body’s tiny building blocks seen only under a microscope. In the middle of each cell is a structure, the nucleus, which is full of deoxyribonucleic acid (DNA), and contains about 100,000 genes which control every activity of the cell. Damage to DNA, for example by tobacco or other harmful substances, can lead to a normal cell becoming cancerous. The cells are bound together by connective tissue to form a variety of organs, such as the skin, heart, lung or liver, together making up the body. Each tissue and organ has cells which have their individual shapes, structures and functions to fulfill. Every cell has a regular lifespan in every organ; it then dies and is replaced by the division of young cells. The body controls the death of old cells and the birth of new cells.

Causes of cancer

There are numerous causes of cancer a few are listed below

• Growing older
• Tobacco
• Sunlight
• Ionizing radiation
• Certain chemicals & other substances
• Some viruses & bacteria
• Certain hormones
• Family history of cancer
• Alcohol
• Poor diet, lack of physical activity or being overweight


• Growing older

The most important risk factor for cancer is growing older. Most cancers occur in people over age of 65. but people of all ages, including children, can get cancer, too.

• Tobacco

Tobacco use is the most preventable cause of death. Each year, more than 180,000 Americans die from cancer that is related to tobacco use.

Using tobacco products or regularly being around tobacco smoke (environmental or secondhand smoke) increases the risk of cancer.

Smokers are more likely than nonsmokers to develop cancer of lung, larynx (voice box), mouth, esophagus, bladder, kidney, throat, stomach, pancreas, or cervix. They also are more likely to develop acute myeloid leukemia (cancer that starts in blood cells).

People who use smokeless tobacco (sniff or chewing tobacco) are at increased risk of cancer of mouth.

• Sunlight

Ultraviolet (UV) radiation comes from the sun, sunlamps, and tanning booths. It causes early aging of the skin and skin damage that can lead to skin cancer.

• Ionizing radiation

Ionizing radiation can cause cell damage that leads to cancer. This kind of radiation comes from rays that enter the earth’s atmosphere from outer space, radioactive fallout, radon gas, x-rays, and other sources.

Radioactive fallout can come from accidents at nuclear power plants or from the production, testing, or use of atomic weapons. People exposed to fallout may have an increased risk of cancer, especially leukemia and cancers of the thyroid, breast, lung, and stomach

Radon is a radioactive gas that you cannot see, smell, or taste. It forms in soil and rocks. People who work in mines may be exposed to radon. In some parts of the country, radon is found in houses. People exposed to radon are at increased risk of lung cancer.

• Certain chemicals & other substances

People who have certain jobs (such as painters, construction workers, in chemical industry) have an increased risk of cancer. Many studies have shown that exposure to asbestos, benzene, benzidine, cadmium, nickel, or vinyl chloride in the work place can cause cancer.

• Some viruses and bacteria

Being infected with certain viruses or bacteria may cause the risk of developing cancer.
HUMAN PAPILLOMAVIRUSE (HPVs)
HEPATITIS B & HEPATITIS C VIRUSES
HUMAN T-CELL LEUKEMIA/LYMPHOMA VIRUS (HTLV-1)
EPSTEIN-BARR VIRUS
HELICOBACTER PYLORI
HIV
HHV8

• Certain hormones

Doctors may recommend hormones (estrogen alone or estrogen along with progestin) to help control problems (such as hot flashes, vaginal dryness, and thinning bones) that may occur during menopause. However studies show that menopausal hormone therapy can cause serious side effects. Hormones may increase the risk of breast cancer, heart attack, stroke, or blood clots

• Family history of cancer

Most cancers develop because of changes (mutations) in genes. A normal cell may become a cancer cell after series of gene changes occur. Tobacco use, certain viruses, or other factors in a person’s lifestyle of environment can cause such changes in certain types of cells.

Some gene changes that increase the risk of cancer are passed from parent to child. These changes are present at birth in all cells of the body.

It is uncommon for cancer to run in a family. However, certain types of cancer do occur more often in some families than in the rest of the population. For example melanoma and cancers of the breast. Most of the time, multiple cases of cancer in a family are just a matter of chance.

• Alcohol

Having more than two drinks each day for many years may increase the chance of developing cancers of the mouth, throat, esophagus, larynx, liver, and breast. The risk increases with the amount of alcohol that a person drinks. For most of these cancers, the risk is higher for a drinker who uses tobacco.

• Poor diet, lack of physical activity, or being overweight

People who have poor diet, do not have enough physical activity, or are overweight may be at increased risk of several types of cancer. For example, studies suggest that people whose diet is high in fat have an increased risk of cancers of colon, uterus, and prostate. Lack of physical activity and being overweight are risk factors for cancers of the breast, colon, esophagus, kidney, and uterus

Cancer prevention

Prevention is defined as the reduction of cancer mortality via reduction in the incidence of cancer. This can be accomplished by avoiding a carcinogen or altering its metabolism; pursuing lifestyle or dietary practices that modify cancer causing factors or genetic predispositions; and/or medical intervention (chemoprevention) to successfully reverse preneoplastic changes.
What you eat and drink, how you live, where you work….all these factors can affect your risk for cancer. Some factors related to cancer prevention are

• Tobacco and cancer
• Sun safety
• Food and fitness
• Environmental carcinogens
• School health
• Prevention & Detection Programs

• Smoking is preventable cause of cancer in our society. We can make people aware of its disadvantages by public services or individual efforts.

• The sun’s UV rays cause the vast majority of skin cancer including melanoma, which can be life threatening. The sun burn will fade, but damage to deeper layers of skin remains and can eventually cause cancer. That’s why sun-safe habits should begin in childhood and a lifetime.

• Your diet can affect your risk for cancer. Eating right, being active, and maintaining a healthy weight are important ways to reduce your risk of cancer-as well as heart disease and diabetes. You should cook smart, take control of your weight, and should have fruits and vegetables in your diet.

• Environmental factors can include smoking, diet, sun exposure, and infectious diseases, as well as chemicals and radiation in our homes and work places. Environmental carcinogens include air pollutants, medical treatments, radiations, chemicals, and consumer products.

• School health isn’t just about what’s taught in the classroom. It’s about creating policies and programs that promote a healthy school environment, thereby reinforcing healthful living. It’s about reinforcing healthy habits every day and every year that kids are in school.

• Prevention and detection programs like ACS (American Cancer Society) help educate you about cancer risks, early detection methods, and prevention.

Cancer therapies

Animal studies have already contributed to the development of a drug that has been described by some as “the vanguard in a new generation of cancer drugs.” Gleevec, a chemotherapy that works by inhibiting a protein that contributes to cancer cell growth, is the first effective treatment for people with chronic myeloid leukemia, Gleevec was developed using cell cultures and mouse studies. Like the research programs devoted to developing a malaria vaccine and treatments for epilepsy and heart disease, cancer research requires the use of many different models. Cell and tissue culture, whole animal models, and clinical (human) studies help scientists better understand both the cause of various diseases and better ways to prevent, treat and possibly cure them. All of these methods were used
in the development of Gleevec. In order to develop a new drug to treat a disease, it is necessary to make use of all of these models. Culture, animal, and human studies each play an important role in the struggle to understand disease and develop cures.

GLEEVEC - A drug that is highly effective in treating chronic myeloid leukemia. Although it took more than a decade of laboratory work to develop Gleevec, the drug gained FDA approval in less than 3 years. Typically, it takes 14 years to win FDA approval by proving that a new drug is safe and effective through clinical trials.

CHEMOTHERAPY-Treatment of a disease with a chemical that has a toxic effect on cancerous tissue (anticancer therapy) or on a disease-producing germ (antibiotic)

A Reader's Toolbox

Women should take a lot of care of the sensitive parts of their body like eyes, perfect breasts and teeth etc. As the health of the child depends on the health of the mother so extra care must be taken to improve it. Women should always take healthy foods to ensure perfect nutrition. Women should go for routine checkup of their complete body so that they can find out any internal changes like breast cancer symptoms or any other malfunctioning of the body as well.

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Effective Learning!

learning essentially has 3 steps. encoding, storing and decoding or retrieving.

Encoding - understanding information that you receive and transform them in to understandable format.

Storing - Most of the information we come across everyday doesn't get into our long term memory. But those information we use consciously for some time will leak into our long term memory.

Initially all information that we come across is stored in our short term memory. Then depending on the significance of the information, how long the information was used consciously and other factors, the information will be stored or will left over. Those factors will also decide how easy those memories can be retrieved.

Retrieve / Decode - Retrieving memory form where we stored.

I just wanted to give a brief overview of the processes involved in learning. Now we'll discuss, how you can use these theories practically to improve your learning.

You can use these easy to use methods. There are two methods that i recommend you to use.

1. SQ3R
2. MURDER

• SQ3R

Survey - Before you start studying a particular section, go through it on the surface and try to get a picture of what you are going to learn

Questions - Try to make some question that you expect to get answered by studying that particular section.

Read - Read the section carefully (This should be a very cognitive process) and try to understand the concepts.

Recite - Try to read out what you have read with out looking at the text. Even if the theory suggest this step, i don't recommend this for science and math students. But you can use this to test your memory on certain formulas and so on.

Review - Although all the steps are important, i find this step very very important. This is the step which require lot of concentration. In this step you have to re memorise and check your understanding of certain principals and concepts. Also you can apply what you just learnt to real world examples and check your understanding. Doing problems from the lesson will fall into this category.

MURDER is a very similar technique. It also use the same principals as SQ3R.

Microscopic Urine Analysis!

In this test, urine is centrifuged at relatively low speed (about 2-3,000 rpm) for 5-10 minutes so the solid materials sediment at the bottom. The sediment is spread on a slide and looked at under a microscope.

Red or white blood cells.

Blood cells are not found in urine normally. Inflammation, disease, or injury to the kidneys, ureters, bladder, or urethra can cause blood in urine. Strenuous exercise, such as running a marathon, can also cause blood in the urine. White blood cells may be a sign of infection or kidney disease.

Casts.

Some types of kidney disease can cause plugs of material (called casts) to form in kidneys (in the distal convoluted tubule (DCT) or the collecting duct ). The casts then get flushed out in the urine. Casts can be made of red or white blood cells, waxy or fatty substances (mucus), or protein. The type of cast in the urine can help show what type of kidney disease may be present.

Hyaline Cast

Red Cell Casts

Crystals.

Healthy people often have only a few crystals in their urine. A large number of crystals, or certain types of crystals, may mean kidney stones are present or there is a problem with body metabolism.

Oxalate Crystals

Bacteria, yeast cells, or parasites.

There are no bacteria, yeast cells, or parasites in urine normally.

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