Overview
Manipal Hospital hosts one of the first PET-CT centers in the entire state of Karnataka, committed to providing state of the art imaging for the diagnosis and management of cancer. PET offers important information for patients and physicians and it’s now available in your community. PET/CT combines the strengths of two well-established imaging modalities, CT for anatomy and PET for function, into a single imaging device. By imaging with the two modalities in a single scan, disease can be both identified and localized, potentially resulting in an earlier diagnosis and more accurate staging.
PET/CT scanners provide accurately aligned anatomical and functional images of a patient, allowing functional abnormalities to be localized and distinguished from normal uptake of the PET tracer, which increases physician confidence in arriving at a correct diagnosis.
Oncology PET CT
PET CT scanning is a very important tool in the staging of cancer including lung neoplasm, solitary pulmonary nodules, Hodgkin’s and non-Hodgkin’s lymphoma, melanoma, esophageal malignancy, breast and colon cancer. Despite the huge progress the medical community has made to advance technology and medical care, the incidence of new cancers suggests there is still a need to do much better. PET is a new technology designed to do just that. This medical scan takes about 45 - 90 minutes to complete. The scanner looks very similar to a CT scanner, but the information it provides is very different.
Clinical Uses of PET and PET/CT in Oncology include but not limited to the following:
• Differentiating benign vs. malignant -- SPN
• Establishing grade of malignancy -- Brain gliomas
• Localization of Tumor .
• Establish local extent of tumor & Detecting loco-regional spread -- staging
• Identifying distant metastasis.
• Treatment planning -- Chemotherapy and Radiation therapy.
• Treatment monitoring .
• Detecting and localizing suspected recurrence
Cardiology
It most accurate non invasive way used in the determining viable myocardium in the management of coronary artery disease and. In patients who are being evaluated for revascularization surgery, it can determine the viability of the involved area of the myocardium which would be an indicator of function recovery after surgical intervention.
Brain Imaging
PET CT is also useful in Brain Imaging, assists in the diagnosis of neurological diseases and disorders including Alzheimer’s. It is proving essential for patients with some neurological disorders. CT and MR scans may render exquisite detail about the structure of the brain -- but can tell nothing about its function. With a single PET image, abnormalities of brain function can be found that would otherwise go undetected. PET can determine if the cause is Alzheimer's disease, blood flow shortages, depression, or some other reason. It can localize the brain site of seizure activity. This is especially important for children with uncontrollable seizures who are candidates for hemispherectomy as cure.
FAQs
What is Positron Emission Tomography?
Positron emission tomography, also called PET imaging or a PET scan, is a diagnostic examination that involves the acquisition of physiologic images based on the detection of radiation from the emission of positrons. Positrons are tiny particles emitted from a radioactive substance administered to the patient. The subsequent images of the human body developed with this technique are used to evaluate a variety of diseases.
PET is a powerful diagnostic test that is having a major impact on the diagnosis and treatment of disease. Because disease is a biological process, and PET is a biological imaging examination, PET can detect and stage most cancers, often before they are evident through other tests. PET can also give physicians important early information about heart disease and many neurological disorders, like Alzheimer's.
A PET scan examines your body's chemistry. Most common medical tests, like CT and MR scans, only show details about the structure of your body. PET is different. It also provides information about function. With a single PET procedure, physicians can collect images of function throughout the entire body, uncovering abnormalities that might otherwise go undetected.
For example, a PET scan is the most accurate, non-invasive way to tell whether or not a tumor is benign or malignant, sparing patient’s expensive, often painful diagnostic surgeries and suggesting treatment options earlier in the course of the disease. And although cancer spreads silently in the body, PET can inspect all organs of the body for cancer in a single examination!
What are some common uses of the procedure?
PET scans are used most often to detect cancer and to examine the effects of cancer therapy by characterizing biochemical changes in the cancer. These scans can be performed on the whole body. PET scans of the heart can be used to determine blood flow to the heart muscle and help evaluate signs of coronary artery disease. PET scans of the heart can also be used to determine if areas of the heart that show decreased function are alive rather than scarred as a result of a prior heart attack, called a myocardial infarction. Combined with a myocardial perfusion study, PET scans allow differentiation of nonfunctioning heart muscle from heart muscle that would benefit from a procedure, such as angioplasty or coronary artery bypass surgery, which would reestablish adequate blood flow and improve heart function. PET scans of the brain are used to evaluate patients who have memory disorders of an undetermined cause, suspected or proven brain tumors or seizure disorders that are not responsive to medical therapy and are therefore candidates for surgery.
How should I prepare for the procedure?
PET CT is usually done on an outpatient basis. Your doctor will give you detailed instructions on how to prepare for your examination. You should wear comfortable, loose-fitting clothes. You should not eat for four hours before the scan. You will be encouraged to drink water. Your doctor will instruct you regarding the use of medications before the test.
Note: Diabetic patients should ask for any specific diet guidelines to control glucose levels during the day of the test.
What does the equipment look like?
You will be taken to an examination room that houses the PET scanner, which has a hole in the middle and looks like a large doughnut. Within this machine are multiple rings of detectors that record the emission of energy from the radioactive substance in your body and permit an image of your body to be obtained. While lying on a cushioned examination table, you will be moved into the hole of the machine. The images are displayed on the monitor of a nearby computer, which is similar in appearance to the personal computer you may have in your home.
How does the procedure work?
Before the examination begins, a radioactive substance is produced in a machine called a cyclotron and attached, or tagged, to a natural body compound, most commonly glucose, but sometimes water or ammonia. Once this substance is administered to the patient, the radioactivity localizes in the appropriate areas of the body and is detected by the PET scanner.
Different colors or degrees of brightness on a PET image represent different levels of tissue or organ function. For example, because healthy tissue uses glucose for energy, it accumulates some of the tagged glucose, which will show up on the PET images. However, cancerous tissue, which uses more glucose than normal tissue, will accumulate more of the substance and appear brighter than normal tissue on the PET images.
How is the procedure performed?
A nurse or technologist will take you into a special injection room, where the radioactive substance is administered as an intravenous injection (although in some cases, it will be given through an existing intravenous line or inhaled as a gas). It will then take approximately 30 to 90 minutes for the substance to travel through your body and accumulate in the tissue under study. During this time, you will be asked to rest quietly and avoid significant movement or talking, which may alter the localization of the administered substance. After that time, scanning begins. This may take 30 to 45 minutes.
Some patients, specifically those with heart disease, may undergo a stress test in which PET scans are obtained while they are at rest and again after undergoing the administration of a pharmaceutical to alter the blood flow to the heart.
Usually, there are no restrictions on daily routine after the test, although you should drink plenty of fluids to flush the radioactive substance from your body.
What will I experience during the procedure?
The administration of the radioactive substance will feel like a slight pinprick if given by intravenous injection. You will then be made as comfortable as possible before you are positioned in the PET scanner for the test. You will be asked to remain still for the duration of the examination. Patients who are claustrophobic may feel some anxiety while positioned in the scanner. Also, some patients find it uncomfortable to hold one position for more than a few minutes. You will not feel anything related to the radioactivity of the substance in your body.
Who interprets the results and how do I get them?
Patients undergo PET because their referring physician has recommended it. A radiologist who has specialized training in PET will interpret the images and forward a report to your referring physician. It usually takes one to three days to interpret, report and deliver the results. In order to facilitate interpretation, you may be asked to bring any previous radiological images with you, such as recent CT (CAT) scans or MRI images.
What are the benefits vs. risks?
- Because PET allows study of body function, it can help physicians detect alterations in biochemical processes that suggest disease before changes in anatomy are apparent with other imaging tests, such as CT or MRI.
- Because the radioactivity is very short-lived, your radiation exposure is low. The substance amount is so small that it does not affect the normal processes of the body.
- The radioactive substance may expose radiation to the fetus in patients who are pregnant or the infants of women who are breast-feeding. The risk to the fetus or infant should be considered in relation to the potential information gain from the result of the PET examination. If you are pregnant, you should inform the PET imaging staff before the examination is performed.
What are the limitations of Positron Emission Tomography?
PET can give false results if a patient's chemical balances are not normal. Specifically, test results of diabetic patients or patients who have eaten within a few hours prior to the examination can be adversely affected because of blood sugar or blood insulin levels.
Also, because the radioactive substance decays quickly and is effective for a short period of time, it must be produced in a laboratory near the PET scanner. It is important to be on time for the appointment and to receive the radioactive substance at the scheduled time. PET must be done by a radiologist who has specialized in nuclear medicine and has substantial experience with PET. Most large medical centers now have PET services available to their patients. Medicare and insurance companies cover many of the applications of PET, and coverage continues to increase.
Finally, the value of a PET scan is enhanced when it is part of a larger diagnostic work-up. This often entails comparison of the PET scan with other imaging studies, such as CT or MRI.
If I'm diagnosed with cancer should I request a PET scan?
PET can effectively pin point the source of many of the most common cancers and give physicians important early information, eliminating the need for redundant tests and diagnostic surgical procedures. Ask your physician if PET- CT scan is right for you.
Is PET painless?
After the injection of a minute amount of the trace solution into a vein, the patient relaxes while the scan is performed. It’s Safe and can be performed in about 2-3 hours as an outpatient procedure.
Can I eat or drink before my scan?
This will depend on the type of study, but typically, you will be asked not to eat or drink anything after midnight the night before your scan.
How much time should I allow?
You can expect to be in the PET Imaging Center for one and a half to three hours. The actual scan itself takes far less time.
How does the procedure work?
To begin the procedure, a small amount of radioactive glucose (or similar tracer) is injected into your bloodstream.
There is no danger to you from this injection. Glucose (also known as sugar) is a common substance every cell in your body needs in order to function. Radioactive glucose must pass multiple quality control measures before it is used for any patient injection. The radiation exposure associated with PET is similar to that associated with a conventional CT scan.
After the injection, you will wait approximately an hour, while the injection material is distributed throughout your body. Then, you will be asked to lie on a table that passes slowly through the scanner. The scanner resembles a CT scanner, but has a much larger opening. Some people fall asleep during the scan.
The Twin Speed MRI scanner is one of the most advanced scanners in the world, equipped with dual gradient coils, permitting both, high speed of scanning for imaging very rapid events in the human physiology and thin sections to permit fine details of the structure.
The MRI scanner is equipped with a complete set of dedicated coils which are designed for each structure being evaluated. This permits the best possible images of the organs and structures, and the finest possible details. Some of the dedicated coils are for the Heart, Abdomen, Spine, Head, Knee, Shoulder, Ankle, wrist, neck, etc.
The most comprehensive imaging of any part of the body will be enhanced by a complete list of all the available MRI imaging sequences. The imaging sequences form the essence of the imaging. There are dedicated sequences for every organ of the body to
Advanced image procession workstations permit 3-D visualization and image processing to get anatomical as well as physiologic information.
Some of the advanced studies possible on the Twin Speed MRI scan include :
Imaging of any part of the human body.
Perfusion Imaging : This is a method of studying the dynamics of the contrast injected in a vein in the arm. Extremely rapid serial imaging is done within a second and repeated to see how the injected material is distributing in the organs. This is useful for grading cancerous tumors as well as blocks in the blood vessels. Brain Perfusion Imaging: This is useful in acute brain strokes as well as brain tumors. Body perfusion Imaging : This is useful in grading the tumors in the body, for example in Liver and Kidneys.
Diffusion imaging : This is highly useful in strokes and tumors.
Tractography and Diffusion Tensor Imaging : Imaging of the tracts connection various areas of the brain.
MR Angiograpy : This can be performed as an out patient procedure, avoiding catheter angiography in many cases. Due to the high speed and dedicated programs, long areas of the body can be evaluated. On the conventional scanners, this required multiple injections and high volume of contrast media.
MR Spectroscopy of Brain : This is a means of studying the physiology and metabolism in diseases. Many Brain diseases and tumors can be accurately diagnosed.
MR Spectroscopy of Body : MR spectroscopy is useful in detecting cancer in the body also, especially the cancers of Breast and Prostate.
Compression Imaging of the Spine : This unique application permits simulation of the forces that will be exerted on the lower back while standing. This permits more accurate assessment6 of the cause of back pain and more precise treatment in low back ache.
MR Mammography : Dedicated coils and imaging sequences will permit imaging ob both breasts simultaneously to detect and grade cancers. Contrast dynamics and spectroscopic studies will help in increasing the accuracy of the diagnosis.
The Volume CT is one of the most advanced CT scanners in the world. It is capable of very fast scans. Any one anatomic region of the body can be scanned in less than 10 seconds. It is also designed for the maximum patient safety. It is equipped with an automatic exposure control so that the radiation dose to the patient can be minimized and still maintain high image quality.
It is possible to scan the body using very thin sections, as thin as 0.65 millimeters when extremely fine details of small structures is required to be studied, for example, the tiny bones inside the ear.
Advanced Image processing software on dedicated workstations can generate 3-D images of any part of the body for planning complex surgeries.
Any part of the human body can be scanned. In addition, the advanced scanner design, the latest software, high speed and thin sections permit new applications for advanced diagnosis of the diseases.
Some of the advanced studies possible on the VCT scanner include :
CT Coronary angiography : This permits screening of people with a medium risk of Heart Disease to find out if there are any blocks or narrowing of the arteries as an out patient procedure. In addition the heart contractility and the ejection fraction can also be measured. Catheter angiography requiring hospitalization can be avoided in those patients who have only mild disease.
CT Coronary angiography for Bypass Patients : Direct catheter angiography can be avoided in most of the patents after bypass surgery on routine follow up.
CT Coronary angiography and Renal Angiography : Many patients with risk of coronary heart disease are also at high risk of narrowing of the arteries isupplying the Kidneys. This can be evaluated as an extension of the CT Coronary Angiography without a separate injection of Contrast media for this purpose.
CT angiography of Head and Neck : This can be performed as an out patient procedure, avoiding catheter angiography in many cases.
CT angiography of body and peripheral arteries : This can be performed as an out patient procedure, avoiding catheter angiography in many cases. Due to the high speed and thin sections, long areas of the body can be evaluated. On the conventional scanners, this required multiple injections and high volume of contrast media.
Brain Perfusion Imaging: This is useful in acute brain strokes as well as brain tumors.
Body perfusion Imaging : This is useful in grading the tumors in the body, for example in Liver and Kidneys.
CT Urography : This gives a detailed view of the structure of the Kidneys, ureters and urinary bladder.
CT Bronchoscopy : This provides a detailed view of the airways of the lungs and in some cases could avoid direct bronchoscopy and anesthesia.
CT Colonography : This is a way by which colonoscopy can be avoided in the follow up of patents with polyps.
Cochlear CT : This is very useful in planning Cochlear Implants. The thin sections can provide all the anatomical details required to plan this complex surgery.
Dental CT : Dedicated software and thin sections will permit dedicated dental scans for cosmetic and dental implant surgery planning.
Poly Trauma evaluation : In accidents there are often injuries to many organs. Time is of essence. The high speed of scanning permits large body areas to be scanned in seconds. The extent of injuries can be accurately assessed and treatment and surgery planned in this life threatening situation.
What is LASIK?
Laser Assisted In-situ Keratomileusis or LASIK, is an outpatient surgical procedure used to treat Myopia (near sight), Hyperopia (far sight) and Astigmatism. In LASIK, your Ophthalmic Surgeon uses a microsurgical instrument and a specialized laser beam to reshape the Cornea. Reshaping your cornea alters the focusing power of the eye, allowing you to become less dependent on glasses or contact lenses. In most people, LASIK allows you to do without them entirely.
Why should you consider LASIK?
LASIK has been a major breakthrough among vision correction techniques. With its outstanding results, LASIK has rapidly gained acceptance as a realistic alternative and enabled millions of people worldwide to enjoy a new found freedom – living their lives without the inconvenience of glasses or contact lenses.
How does LASIK work?
The surgeon creates an ultra thin corneal flap, using a highly specialized cutting instrument called a Microkeratome. The Excimer Laser is then used to reshape the cornea under the flap. The flap is replaced and adheres firmly and fully without the need for stitches. With the flap in place, the eye recovers quickly and vision is rapidly restored with minimal discomfort.
The cornea provides two thirds of the eye’s focusing power. Altering its shape changes the power of the eye. LASIK flattens the cornea to correct myopia or steepens the cornea for hyperopia. The reshaping process can also be used to correct astigmatism at the same time.
Our Technology
We have, after exhaustive research, invested in the MEL 80 Excimer LAser, manufactured by Carl Zeiss, Germany, renowned in the ophthalmic world for their innovative and cutting edge equipment.
The outstanding features of the MEL 80 are:
The smallest laser spot size of 0.7mm, which enables detailed and accurate reshaping of the cornea.
• With its firing frequency of 250 spots per second, the MEL 80 completes the treatment in record time, with unsurpassed accuracy and predictability
• Equipped with an accurate eye tracker which instantly compensates for eye movements allowing safe treatment every time
• Equipped with the WASCA Wave front Analyzer the leading diagnostic instrument of its type. With several advancements over its competitors, the WASCAA Analyzer can measure 1452 points on the eye in 13 milliseconds. Every eye is unique and the WASCA Analyzer is able to map out this individual variation in the profile of each eye. This information allows us to offer CUSTOMISED laser correction to all who are suitable.
Who is suitable for LASIK?
You may consider this procedure if you:
• Are over 20 years old and have had a stable prescription for at least 1 year
• Have healthy eyes with no diseases (e.g. Cataract, Glaucoma)
• Are within the range of correction – Myopia upto -10 dioptres
Hyperopia upto +5 dioptres
Astigmatism upto +5 dioptres
• Are in good general health
• Are not pregnant nor planning pregnancy in the immediate future
What to expect from LASIK?
• Vision- There is usually a very rapid recovery of vision after LASIK and most people will see well within a day or two. You will be able to come in for treatment over the weekend and return to work a new person, without taking time off from work.
• Pain – The procedure and recovery is painless
• Restrictions – There are very few restrictions during recovery. Antibiotic and anti-inflammatory drops have to be instilled for about a month after surgery.
• Enhancement- Most people attain the clear vision they hoped for after one treatment. In the rare event of regression or if the desired correction is not achieved by your first procedure, then your consultant may recommend an enhancement, which is an easier procedure
What are the risks, complications and side effects?
Like any surgery on the body, LASIK has risks and complications that should be carefully considered. Sight threatening risks are extremely rare and should not be a cause for concern. Most complications are minor and can be treated without any loss of vision. Some people experience temporary side effects after LASIK that usually disappear in time.