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Doctor insights on: Pet Scan

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Dr. Guido Davidzon
291 Doctors shared insights

Pet Scan (Overview)

Pet scans most often use a radioactive form of glucose, the energy source for most of the cells in our bodies. The pet scanner can detect and measure how much of the radioactive glucose analog, f-18 fdg, is in a particular organ or region. The areas using more glucose are hyper metabolic and generally more worrisome. Our brains and sometimes hearts prefer glucose as food, making it hard to see.


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What is a pet scan?

What is a pet scan?

NUCLEAR CT SCAN: Pet scan is one type of nuclear ct scan (other type is called spect scan) that uses gamma rays as opposed to x-rays used in conventional or standard ct scan. ...Read more

Dr. Guido Davidzon
291 Doctors shared insights

Pet Scan (Overview)

Pet scans most often use a radioactive form of glucose, the energy source for most of the cells in our bodies. The pet scanner can detect and measure how much of the radioactive glucose analog, f-18 fdg, is in a particular organ or region. The areas using more glucose are hyper metabolic and generally more worrisome. Our brains and sometimes hearts prefer glucose as food, making it hard to see.


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What can a pet scan show?

What can a pet scan show?

What is the question: Currently pet scans are widely use for evaluation of glucose metabolism in the body.
In oncology, is use to for initial metabolic characterization of tumors, metastases as well as for treatment response and surveillance. In cardiology, pet scans are use to assess heart ischemia and viability and in neurology the study is use to evaluate cognitive disorders, epilepsy and brain tumors ...Read more

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What is suv on a pet scan?

What is suv on a pet scan?

StandardUptakeValue: Suv simply stands for standard uptake value of a certain area on a scan (lesion, lymph node, etc). This is typically used to standardize pet scans between institutions and physicians. Studies show that maximum suvs of certain lesions are more indicative of cancer. This takes out some of the subjectiveness of reading the studies because by looking at this value, one can decide if it is high or low. ...Read more

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Are suv on pet scan gamma?

Are suv on pet scan gamma?

SUV...: Suv stands for standardized uptake value. It is used for semi-quantitative analysis on pet scan. It tells the amount of glucose uptake or hypermetabolism of a tumor. ...Read more

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What is a pet scan used for?

What is a pet scan used for?

Approved for cancer: Pet scan are approved for staging, response assessment and surveillance of certain types of cancers. However, any pathologic process that augments the consumption of glucose (such as infection or inflammation) can be evaluated, though these indications are not currently covered. In addition, pet scans are used to evaluate for brain cognitive disorder, heart ischemia and myocardial viability. ...Read more

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How is a pet scan conducted?

How is a pet scan conducted?

Much like a CT: Pet/ct is a scanner which looks a lot like a ct scanner.

However, pet scans most often use a radioactive form of glucose, the energy source for most of the cells in our bodies. The pet scanner can detect and measure how much of the radioactive glucose analog, f-18 fdg, is in a particular organ or region.

The areas using more glucose are hyper metabolic and generally more concerning. ...Read more

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Why do people get a pet scan?

PETs...: Pet scans can be used for a variety of purposes depending on the specific radiotracer used. Most commonly, pets are done with FDG (glucose) for oncologic reasons. Other uses of pet include cardiac pet (viability and perfusion studies) or neurologic pet (for seizure focus mapping or dementia). ...Read more

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What is pet scan of the heartbfor?

What is pet scan of the heartbfor?

Blood Flow: A pet/ct with n13 ammonia allows evaluation of the flow of blood in the cardiac vessels, and is useful in determining if a patient would benefit from a more invasive test, called a cardiac angiogram, to better view suspected vessel narrowings (called stenoses) and possibly treat them with angioplasty and stenting. ...Read more

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Can a PET scan cause an increase in?

Can a PET scan cause an increase in?

What is the question: Your question is incomplete. Can you please resubmit so that we can answer it ...Read more

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What are the limitations of a pet scan?

What are the limitations of a pet scan?

Tricky: Not all cancers are hypermetabolic on pet scans and not all hypermetabolic activity in a pet scan is cancer. Inflammation/infection can also show hypermetabolic activity. Pet scans are performed in conjugation with ct (pet/ct) and though pet is great for detecting metabolism (high sensitivity), its specificity is not as great and also has poor anatomic resolution. Reading a pet requires care/skil. ...Read more

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How much pet scan is useful for my son?

How much pet scan is useful for my son?

More info: It would depend on what disease was being looked for. Pet/ct looks at function, while MRI and ct look at the anatomy primarily. ...Read more

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What does an abnormal pet scan look like?

What does an abnormal pet scan look like?

Increased activity: Where it shouldn't be. All organ systems have some metabolic activity, but active organs, such as the heart, kidneys and brain are normally very active. However, the bones, lungs and muscle are not. Various color schemes can be used to detect abnormal uptake. The yellow orange areas show metastatic disease in the liver and bone. ...Read more

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What number of times pet scan in whole life?

What number of times pet scan in whole life?

As many as needed: Nobody gets a PET scan for no reason. Your doctor must be ordering it for a very good reason, it is expensive. If your doctor thinks that you have cancer or other problems that only PET can diagnose, then you need to have the PET> ...Read more

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Is it possible for pet scans to make a mistake?

Is it possible for pet scans to make a mistake?

Yes: Yes. As with all tests there can be some false positives and false negatives. If you think there may be a mistake you can always get a second opinion. ...Read more

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What are pet scans? What exactly is a pet scan?

What are pet scans? What exactly is a pet scan?

Positron Emission: These studies are done by injecting a special "dye" that is attached to a specific molecule. Most of the pet today is done using FDG (a glucose/sugar look-a-like molecule). Wherever this molecule is used/concentrated, the pet scan is brighter. Hence, tumors/infections (which use a lot of energy/sugar/fdg) are bright on such studies. More: http://en. Wikipedia. Org/wiki/positron_emission_tomography. ...Read more

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Does anybody know what an abnormal pet scan is?

Does anybody know what an abnormal pet scan is?

Yes: But I cannot give you the answer without knowing why the scan was performed.
An abnormal scan most likely is because there is an area in your body that is more metabolically active, than expected.
But pet scans are done as pet/ct scans and abnormality could be in the ct part. ..Which could be anything. ..Anatomically not "normal". These ct findings could be "normal" for you but not me. Ask ur md. ...Read more

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Can someone be with me while I have a pet scan?

Can someone be with me while I have a pet scan?

Probably: I would not recommend a child or pregnant woman be the companion. The amount of radiation dose is minimal to caretaker as long as has usual distance of 3.5 feet from patient. Study involves injection of isotope and sitting in quiet room for about 45 minutes. Then pet ct scan performed possibly for another half hour. Typical dose would be about 0.13 msv. Round-trip flight from new york to tokyo 0.13msv. ...Read more

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What chemical is in the injection for pet scans?

What chemical is in the injection for pet scans?

F18-FDG: Different pet tracers exist for positron emitting scans (pet) scans. The most widely used for oncologic purpose is f18-fdg (fluorine-18-fludeoxyglucose) which is a modified glucose (fdg) attached to a radionuclide (f18) that emits gamma photons of 511 kev (energy) and has a physical half-life of 110 minutes. ...Read more

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How does metal affect the results of a pet scan?

How does metal affect the results of a pet scan?

Usually not much: Metal can block the gamma rays that are emitted by the patient, and block the xrays from the ct portion of the pet/ct, which can create errors on one portion of the exam (called the attenuation corrected scan).

However, the original pet data from the scan (uncorrected) is always available for review, so if the standard images have artifact on them, the uncorrected images can be reviewed. ...Read more

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What part of the body does a whole pet scan show?

What part of the body does a whole pet scan show?

Eyes to thighs: Even though the study is called whole body pet/ct, most often the image acquisition is from the eyes to thighs. The parts of the body that are included varies from center to center and also depends on the patient's symptoms and cancer histopathology. For e.g. Melanomas can metastasize anywhere in the body and thus real whole body scans are obtained (skull vertex to toes). ...Read more

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Are pet scans accurate or are other scans better?

Are pet scans accurate or are other scans better?

Depends: Depends on what you are looking for. PET scan usually uses a glucose based tracer to evaluate metabolic activity which can be increased in tumors. All modalities have a certain rate of false positives and negatives. Sometimes multiple modalities can each give you different information to obtain a complete evaluation. ...Read more

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What is the definition or description of: pet scan?

What is the definition or description of: pet scan?

Physiology of lesion: Pet scans most often use a radioactive form of glucose, the energy source for most of the cells in our bodies. The pet scanner can detect and measure how much of the radioactive glucose analog, f-18 fdg, is in a particular organ or region. The areas using more glucose are hyper metabolic and generally more worrisome. Our brains and sometimes hearts prefer glucose as food, making it hard to see. ...Read more

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How many pet scans can a person safely have in 2 months?

Depends: Radiation received from pet ct is relatively high compared to other imaging tests. Pet ct is mainly used for demonstrating metastatic disease, making decisions about effect of therapy, and looking for recurrence. Pet ct has helped prolong life because it can detect small lesions not seen by other tests. Wise decision should be made judging radiation risk versus positive benefit to the patient. ...Read more

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How long is the ideal time between one pet scan and another?

How long is the ideal time between one pet scan and another?

Depends disease/time: Pet scan may be obtained for different purpose: staging disease, assessing treatment response or surveillance. Prior to assess tumor response your physician may want you to receive variable x number of treatments. If you are receiving treatment with radiation, you should typically wait 2-3 months for post-radiation inflammation to be minimal. Then surveillance scans may be done yearly. ...Read more

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Hi, I had a PET scan Tuesday, got report today. "9MM multilobulated modular density, size stable.?

Hi, I had a PET scan Tuesday, got report today. "9MM multilobulated modular density, size stable.?

Missing info: The most important piece of information is missing. The PET scan shows metabolic activity usually measured in SUV's.

Before I would make any assessment, I want to know what the SUV is. Was it mentioned in the report? ...Read more

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I want to have an upcoming PET scan compared to the one 3 months earlier. Do I request a comparative report or a comparative study? What exactly?

I want to have an upcoming PET scan compared to the one 3 months earlier. Do I request a comparative report or a comparative study? What exactly?

I don't: Know any facility that would perform a PET scan without a physician's order, so you probably don't need to worry about how to word the request. If you already have the order and want to make sure the facility has the proper information, when you call to schedule the test, tell them that you had a prior PET scan (when and where) and that this is a follow up study. ...Read more

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What is the difference between mris & pet scans?

What is the difference between mris & pet scans?

Anatomy vs Physiolog: Mri and ct look at the structure of the body, the anatomy, and the way diseases change or distort it.

Pet looks at the physiology, or how the body uses, or metabolizes something. For pet, the most common metabolism pathway looked at is how glucose is used. A low dose ct is often acquired at the same time as the pet (as in pet/ct scan), to correlate the pet findings with the ct anatomy. ...Read more