Total-body PET: Maximizing sensitivity for clinical research and patient care

Did You Know Having A Pet At Home Could Help You Fight Depression? It’s True, According To This Study.

The unconditional love and support of a pet can help you calm down instantly. It also has therapeutic benefits on owners suffering from long-term mental health conditions, says a new study.

The findings were published in the open access journal BMC Psychiatry. Researchers from the University of Manchester suggested that pets should be considered as a main source of support in the management of long-term mental health problems.


“The people we spoke to, through the course of this study, felt their pet played a range of positive roles such as helping them to manage stigma associated with their mental health by providing acceptance without judgement,” said lead study author Dr Helen Brooks from the University of Manchester.

“Pets were also considered particularly useful during times of crisis. In this way, pets provided a unique form of validation through unconditional support, which they were often not receiving from other family or social relationships. Despite the identified benefits of pet ownership, pets were neither considered nor incorporated into the individual care plans for any of the people in our study,” Brooks added.

The team interviewed 54 participants, aged 18 and above, who were under the care of community-based mental health services and had been diagnosed with a severe mental illness.

The participants were asked to rate the importance of members of their personal network including friends, family, health professionals, pets, hobbies, places, activities and objects, by placing them in a diagram of three concentric circles.

Anything placed in the central circle was considered most important; the middle circle was of secondary importance and the outer circle was for those considered of lesser importance.

The pets played an important role in the social networks of people managing a long-term mental health problem, as 60% placed their pet in the central most important circle and 20 percent placed their pet in the second circle.

The participants stated that their pet helped by distracting them from symptoms and upsetting experiences such as hearing voices or suicidal thoughts.

PET, MRI find link between TBI and Alzheimer’s

An easy-to-use, automated computer algorithm based on diffusion-tensor MRI (DTI-MRI) scanning is helping to evaluate people with mild traumatic brain injury (TBI). Researchers hope the algorithm will spur more widespread adoption of DTI-MRI in the clinical setting, according to a study published February 1 in Radiology.

The researchers used Shannon entropy, an information and mathematical model designed to look at areas of disorder in complex biological systems, such as the brain. In this case, Shannon entropy works in parallel with DTI-MRI to measure the amount of damage done to white-matter tracts in concussed patients (Radiology, February 1, 2016).

As the amount of information or complexity contained in the data is accumulated by Shannon entropy, the algorithm can determine the degree of injury and its aftereffects. In other words, a healthy brain has high entropy, while a brain with white-matter damage from a mild traumatic trauma may lose some of its complexity and have less entropy.

“The more injury indicated by Shannon entropy, the more likely there could be a longer recovery time,” said study co-author Dr. Lea Alhilali, a neuroradiologist with the Barrow Neurological Institute in Phoenix. “It also can better detect in a patient whether he or she is at future risk of neurocognitive issues.”

Severe aftereffects

Headaches and migraines are common among people with mild TBI. Post-traumatic migraines have especially high morbidity, are associated with lower neurocognitive test scores, and can aggravate other post-traumatic symptoms that delay recovery, the authors noted.

In fact, previous research by Alhilali and colleagues used DTI-MRI to uncover distinct injury patterns in the brains of people with concussion-related depression or anxiety.

Alhilali explained that many changes occur in the brain after a concussion. The long, thin parts of the nerve cell that send impulses from cell to cell — known as axons — may swell, which causes an increase in fractional anisotropy values. If the axons are damaged, fractional anisotropy values will decrease.

“If all you look at is the average of these two different [fractional anisotropy] directions, you don’t see a change,” she said. “Because Shannon entropy measures how complex the dataset is, if one type of injury moves the fractional anisotropy up and one moves it down, there are two different states, and the Shannon entropy detects the complexity [of the changes].”

That deficiency in DTI-MRI and fractional anisotropy measurements led to the current endeavor.

“We felt that the way radiologists were using diffusion-tensor imaging to analyze water tracts was not sufficient to accurately detect white-matter injuries across the spectrum of concussion patients,” Alhilali said. “So, we decided to utilize Shannon entropy to analyze the diffusion-tensor images to see how complex the dataset is.”

Targeting mild TBI

The researchers reviewed radiology reports from the University of Pittsburgh Medical Center between January 2006 and January 2014. They found 74 patients with mild TBI, who had a mean age of 18 years (range, 10-47 years). Within this group, 30 patients had experienced a prior concussion and 57 had post-traumatic migraines.

The study also included 22 healthy control subjects and 20 control subjects with migraine headaches. The median time from injury to clinical presentation was 20 days (range, 0-506 days). The most common types of trauma were sports injuries (43 patients, 57%) and motor vehicle accidents (nine patients, 12%).

Diffusion-tensor imaging was performed with a 1.5-tesla MRI scanner (Signa, GE Healthcare) with a standard head coil to acquire fractional anisotropy maps.

The researchers calculated mean fractional anisotropy values and Shannon entropy scores from DTI total brain fractional anisotropy maps and compared the results between the subject groups. They also analyzed the outcomes of participants with and without post-traumatic migraines.

Mild TBI values

Patients with mild TBI tended to have lower mean fractional anisotropy values (0.379), compared with the healthy control subjects (0.383) and control subjects who experienced migraines (0.382), Alhilali and colleagues found. The mild TBI patients also had significantly lower Shannon entropy scores (0.737) than both the healthy control subjects (0.808) and control subjects with migraines (0.795).

There was no significant difference between healthy control subjects and control subjects with migraines for either fractional anisotropy or Shannon entropy values.

Based on area under the curve (AUC) analysis, Shannon entropy (0.85) outperformed mean fractional anisotropy (0.52) in determining which patients with mild TBI developed post-traumatic migraines (p < 0.001). In addition, patients with Shannon entropy of less than 0.750 were “approximately 16 times more likely to have experienced mild TBI and were three times more likely to develop post-traumatic migraine,” the authors wrote.

Post-traumatic migraine was also a factor in determining recovery time. It took patients with migraines a median 51.9 days to recover, compared with a median 39.4 days for those without migraines.

Shannon entropy’s future

While Shannon entropy has been used in electrocardiographic (ECG) analysis, it is not well-known or widely used in radiology.

“That is what is very novel about this topic,” Alhilali said. “Not only has it never been applied to the imaging of brain white matter, but it also was successful in detecting white-matter injuries.”

The authors speculated that Shannon entropy analysis of DTI might help clinicians more accurately diagnose concussion, anticipate patients’ symptoms, and predict prognosis in mild TBI.

Alhilali said a benefit of Shannon entropy is that it is easy to use.

“When you do the analysis, which is an easy automated computer algorithm, you get a number, which is very easy for a clinician, radiologist, or researcher to understand,” she explained. “A lower number means less complexity in the white matter and a higher number means greater complexity and recovery from mild TBI.”

The Barrow Neurological Institute currently has an ongoing study using athletes from Arizona State University to explore factors including accelerometer data, molecular markers, and blood samples, correlating that information with imaging markers of injury.

“We hope that Shannon entropy can be one imaging marker we can use to correlate with mechanical and molecular markers of injury that we detected in other portions of the study,” Alhilali said.

She does not think that Shannon entropy will change “the way we analyze diffusion-tensor imaging, because it is a very powerful tool that has yet to find a strong clinical use,” she added. “Because there is a great deal of variability in diffusion-tensor imaging measurements, it requires group statistics and comparable analysis that will not be performed by anyone in the clinical setting.”

Therefore, she hopes Shannon entropy will help move DTI to the forefront, to be used on individual patients where the results would be more automated and more easily interpreted.

“I think it will help to change the way we analyze diffusion-tensor imaging beyond analyzing injury patterns and mild traumatic brain injury and many other fields in which we use [DTI] for research purposes,” she said. “Perhaps Shannon entropy can bring DTI more into the clinical field.”

FDA Facts: Jerky Pet Treats.

Hundreds of dogs killed by contaminated jerky treats made in China; FDA still clueless of cause

Thousands of family dogs across the USA have been sickened by pet jerky treats made in China, and nearly 600 dogs have died. TheFDA has issued a warning over the deadly jerky treats but has not forced any sort of product recall.

So far, the cause of the fatalities remains a mystery. The FDA says it has tested jerky treats for heavy metals, pesticides, antibiotics, chemicals and even Salmonella but cannot find the cause. The agency is warning pet owners to watch their pets for symptoms of poisoning which may include “decreased appetite, decreased activity, vomiting, diarrhea (sometimes with blood or mucus), increased water consumption and / or increased urination.”

According to USA Today, the deadly jerky treats “come mostly from China,” and the number of dogs sickened or killed by these treats has been rising all year.
The treats causing this epidemic of death, says USA Today, are “made of chicken, duck, sweet potatoes or dried fruit.”


Most consumers do not fully realize that pet treats do NOT have to list their country of origin. Many pet treats are highly deceptive on their packaging, sometimes showing a logo of the continental USA and claiming to be “made with beef from the USA” even though the treats themselves are manufactured in China using toxic chemicals.

The FDA has not issued a recall on the brands it suspects are causing these deaths. This is one of the problems with the agency: it already knows which products are killing dogs, but it has so far failed to release that information to the public. As a result, as more and more people learn about this, all pet treat manufacturers will suffer because consumers will shun the entire product category.

In truth, there are perfectly healthy, safe and even nutritious pet treats made in the USA and other countries, yet due to a lack of labeling laws, it is virtually impossible for consumers to know which country the pet treats they buy are coming from.

This is why we need stronger labeling requirements that mandate the disclosure of things like country of origin, GMOs and even heavy metals contamination. Currently none of these things have to be listed on the label.

Even those of us who believe in smaller government recognize the important role of government in enforcing a “level playing field” through honest labeling. Only with this information can consumers make informed decisions about what they wish to buy (or avoid buying).

Until that happens, countless more dogs, cats and even our own children will die from contaminated food products. These are deaths that could have been avoided if we only had honest labeling laws in place that, for starters, clearly list the country of origin. While that regulation is in place for human foods, it does not exist for pet foods.

US appeal over deadly pet treats

FDA warns of pet illness linked to jerky treats.


A pair of pug dogs getting a taste of Kohr Brothers Frozen Custard in Rehoboth Beach, Delaware on 19 June 2013

US food safety officials are appealing for help from pet owners to find the cause of an outbreak of deadly sickness in dogs who ate jerky-style treats.

The Food and Drug Administration (FDA) says 3,600 dogs and 10 cats have fallen ill after eating the treats since 2007. About 580 of those pets have died.

But the exact cause of the sickness, which can lead to kidney failure and gastrointestinal bleeding, is unclear.

Most of the jerky treats implicated have been made in China, the FDA said.

After running more than 1,200 tests, visiting pet-treat manufacturing plants in China and working with researchers, state labs and foreign governments, food safety officials are now approaching veterinarians and pet owners for more information.

“This is one of the most elusive and mysterious outbreaks we’ve encountered,” Dr Bernadette Dunham, head of the FDA veterinary medicine centre, said in a statement.

Pets’ symptoms have included reduced appetite, decreased activity, vomiting and diarrhoea within hours of eating treats sold as jerky tenders or strips made of chicken, duck, sweet potatoes or dried fruit.

“Our fervent hope as animal lovers,” Dr Dunham said, “is that we will soon find the cause of, and put a stop to, these illnesses.”

Rabies Vaccine Dropped from the Sky

Story at-a-glance

  • There are only 2-4 human rabies cases in the US each year, but annual prevention costs are more than $300 million
  • The Texas Department of Health is using helicopters to spread 100,000 rabies vaccines for skunks in the wilderness; other states have also conducted similar vaccination efforts
  • No one knows if such programs are effective or if the indiscriminate spreading of a pharmaceutical product into the environment is going to have any unforeseen consequences to wildlife or the surrounding ecosystem.
  • rabies

In 2009, there were just four human cases of rabies in the US. In 2010, there were two1… yet each year, the US spends more than $300 million for rabies prevention,2 which includes the vaccination of companion animals, animal control programs, maintenance of rabies laboratories and medical costs.

Even at the turn of the century, rabies-related human deaths only numbered around 100 annually, and by the 1990s, this had dropped to one or two.  While rabies is a serious, potentially deadly, illness, it is most often transmitted through the bite of a rabid wild animal – a risk factor that is negligible for many in the US.

Texas Department of Health Is Dropping Experimental Rabies Vaccines from the Sky

About 92 percent of the reported rabies cases in 2010 were in wild animals, including raccoons, skunks, bats, foxes, rodents and others. This poses a theoretical risk not only to humans but also to family pets, which could then transmit rabies to their owners.

Nonetheless, human rabies cases remain extremely rare… but efforts are still underway to knock out the rabies virus in wild skunk populations in Texas.

The Texas Department of Health is actually using helicopters to spread 100,000 rabies vaccines in two counties. The vaccines, which are contained in plastic cases coated with fishmeal to entice wildlife to eat them, are part of a pilot program to help reduce the number of rabid skunks in the area.

No one knows yet if the program is going to work – skunks will need to be caught and tested for rabies 30-60 days after the vaccines are dropped – or if the indiscriminate spreading of a pharmaceutical product into the environment is going to have any unforeseen consequences to wildlife or the surrounding ecosystem.

Should Wildlife Be Vaccinated Against a Disease That Infects 2-4 People a Year?

It’s also unclear why Texas is taking such aggressive measures against rabies. There has so far been only one reported case of human rabies in Texas in 2013, and the man was exposed in Guatemala, Mexico — not in Texas. The last case of human rabies in Texas prior to that was in 2009 and prior to that in 2004 – for a total of just 6 human cases in the last decade.3

For comparison, there were 2,390 cases of campylobacteriosis in Texas in 2012 alone… an illness largely spread by contaminated poultry raised on concentrated animal feeding operations (CAFOs). This illness, too, can be deadly if it infects a person with a compromised immune system, yet we’re not hearing about widespread efforts to curb its transmission…

Even if you factor in data from the US Centers for Disease Control and Prevention (CDC), which states there were 6,153 reported cases of rabies in animals in 2010, that’s for animals in the entire US, and not only skunks but also raccoons, foxes, bats and others. Texas isn’t the only state to opt for preventative rabies vaccination of wildlife, either. According to the Human Society of the United States (HSUS):4

“Federal and state wildlife officials have been vaccinating wildlife in many regions over the past 15 years. They distribute vaccine-laden baits that the target animals eat and thereby vaccinate themselves. Right now, oral rabies vaccination of wildlife focuses on halting the spread of specific types of rabies in targeted carrier species. Next, it’s hoped that this tool can shrink the diseases’ range.”

The end question remains the same, not only for Texas but for the entire US: is it really necessary to spend $300 million a year on rabies prevention… and what are the potential consequences of vaccinating wildlife?

What Exactly Is Rabies?

Rabies is a viral disease that most often enters your body through a bite or wound contaminated by the saliva from an infected animal. If it manages to infect the central nervous system, it can lead to early symptoms that include fever, headache, weakness and discomfort. As the disease progresses, it can lead to insomnia, anxiety, confusion, paralysis, hallucinations, difficulty swallowing, fear of water and death.

If you have been bitten by a wild animal (or a dog with unknown rabies status), wash the wound thoroughly with soap and water, as this will help to decrease your risk of infection.

Next, talk to a doctor about your next steps. He or she will probably contact the local or state health department and, if it’s deemed that the animal was rabid or at high risk of being rabid, you may need to start postexposure prophylaxis (PEP), which consists of a series of vaccines that can protect you from developing rabies. But remember, though rabies is serious, and frightening, it’s extremely rare. HSUS puts it into perspective:

Given all the media attention that rabies regularly receives, it may be somewhat surprising to learn that very few people die from rabies nationwide each year. Over the past 10 years, rabies has killed only a total of 28 people in the U.S. This amounts to fewer than 3 fatalities a year nationwide.

People who contracted rabies in the United States were mostly infected by a bat. Most didn’t even know they were bitten. Some may have been sleeping when bitten. Others handled a bat bare-handed without realizing they’d been potentially exposed to rabies. But don’t panic over every bat sighting. Less than one-half of one percent of all bats in North America carries rabies. Although raccoons suffer from rabies more than any other mammal in the United States (about 35 percent of all animal rabies cases), only one human death from the raccoon strain of rabies has been recorded in the United States.”

Pet therapy: Man’s best friend as healer.

Animal-assisted therapy can help healing and lessen depression and fatigue.

Is medicine going to the dogs? Yes, but in a good way. Pet therapy is gaining fans in health care and beyond. Find out what’s behind this growing trend.

What is pet therapy?

Pet therapy is a broad term that includes animal-assisted therapy and other animal-assisted activities. Animal-assisted therapy is a growing field that uses dogs or other animals to help people recover from or better cope with health problems, such as heart disease, cancer and mental health disorders.

Animal-assisted activities, on the other hand, have a more general purpose, such as providing comfort and enjoyment for nursing home residents.

How does animal-assisted therapy work?

Imagine you’re in the hospital. Your doctor mentions the hospital’s animal-assisted therapy program and asks if you’d be interested. You say yes, and your doctor arranges for someone to tell you more about the program. Soon after that, an assistance dog and its handler visit your hospital room. They stay for 10 or 15 minutes. You’re invited to pet the dog and ask the handler questions.

After the visit, you realize you’re smiling. And you feel a little less tired and a bit more optimistic. You can’t wait to tell your family all about that charming canine. In fact, you’re already looking forward to the dog’s next visit.

Who can benefit from animal-assisted therapy?

Animal-assisted therapy can significantly reduce pain, anxiety, depression and fatigue in people with a range of health problems:

And it’s not only the ill person who reaps the benefits. Family members and friends who sit in on animal visits say they feel better, too.

Pet therapy is also being used in nonmedical settings, such as universities and community programs, to help people deal with anxiety and stress.

Does pet therapy have risks?

The biggest concern, particularly in hospitals, is safety and sanitation. Most hospitals and other facilities that use pet therapy have stringent rules to ensure that the animals are clean, vaccinated, well trained and screened for appropriate behavior.

It’s also important to note the Centers for Disease Control and Prevention has never received a report of infection from animal-assisted therapy.

Animal-assisted therapy in action

Jack, known as Dr. Jack by his colleagues, is a miniature pinscher and the first facility-based assistance dog (service dog) to join Mayo Clinic‘s team in Rochester, Minn. A fully credentialed service dog, Jack has worked at Mayo Clinic since 2002.

Jack spends time with patients helping them work toward their recovery goals. For example, Jack and his trainer worked with a 5-year-old girl recovering from spinal surgery. Jack helped her relearn how to walk, taking a step backward each time she took a step forward. She also gave Jack a “checkup” each morning, which helped keep her moving. Eventually, she took Jack for walks with the help of a walker.

In addition to Jack, more than a dozen certified therapy dogs are part of Mayo Clinic’s Caring Canines program. They make regular visits to various hospital departments and even make special visits on request.

Source: Mayo clinic house call

New Parasite Prevalence Maps Help Pet Owners Prepare.

The Companion Animal Parasite Council (CAPC) has redesigned its website1 for pet owners and now features a set of maps you can check for information on parasite prevalence in a specific area.

If you’re only interested in heartworm disease, you can select your state from a drop-down menu on the right side of the home page to see the infection risk for your state. If you’d like more extensive information, you can view the entire U.S. map.

If you choose the second option, you can find out the risk for several different diseases for dogs and cats individually, by state. The maps include infection rates for:

  • Tick borne diseases (Lyme disease, ehrlichiosis and anaplasmosis)
  • Intestinal parasites (roundworm, hookworm and whipworm)
  • Heartworm

You can also click on a state and see infection rates for individual counties, then hover your mouse over a county to see its name.

According to Dr. Christopher Carpenter, executive director of CAPC, “Our unique parasite prevalence maps provide localized statistics about diseases that affect dogs and cats in consumers’ backyards, and we update them monthly.”

Keep Your Pet Safe from Overuse of Parasite Preventives

I think these maps are useful for pet owners looking for general information about the prevalence of a certain disease in a certain location. The intent of the maps is to “… help drive clinic visits,” according to Dr. Carpenter, because “People respond to and appreciate it when experts share pertinent information.”

He goes on to say that CAPC hopes veterinarians leverage the maps “… to strengthen client relationships and consistently ‘tap consumers on the shoulder’ with facts that underscore the risk of parasitic disease that exists everywhere.”

Since the Companion Animal Parasite Council is sponsored by a “Who’s Who” list of major veterinary drug manufacturers, I think it’s safe to assume the real intent of the maps is to get pet owners to buy into the belief that every dog and cat in the country should be on parasite preventives year-round.

And while I agree pet owners appreciate learning information pertinent to the health of their furry family members, I think it’s extremely irresponsible of veterinarians to encourage the overuse of parasite preventives. These drugs, like all drugs, have side effects.

Just because a drug is used as a preventive doesn’t automatically put it in the category of “better safe than sorry.” This is a lesson the traditional veterinary community is slowly learning about vaccines. Every single thing we put into or onto an animal should be carefully assessed to insure its benefits outweigh its risks.

And keep in mind that even pets loaded down to the point of toxicosis with chemical preventives still frequently wind up with pests and parasites. There is no absolutely foolproof method for keeping every single pet protected from every single pest.

Around this time last year I saw my first dog patient with Lyme disease AND heartworm disease – conditions she acquired while taking a monthly, year-round heartworm preventive drug AND a spot-on flea/tick preventive prescribed by her regular vet. This is a good illustration of the ineffectiveness of some of these drugs, as well as the fact that parasites are growing resistant to them because they are being overused.

Preventing Tick Borne Diseases

  • In the spring, summer and fall, avoid tick-infested areas.
  • If you live where ticks are a significant problem, check your pet for the little blood suckers twice each day. Look over his entire body, including hidden crevices like those in the ear, underneath his collar, in the webs of his feet, and underneath his tail. If you find a tick, make sure to remove it safely.
  • Use a safe tick repellent like Natural Flea and Tick Defense. If you live in a Lyme endemic region of the U.S., your veterinarian will probably recommend you use a chemical repellent. Remember: it’s important to investigate the risks and benefits of any medication before you give it to your pet. Natural repellents are NOT the same as toxic preventives … they are not a guarantee your pet won’t be bitten by ticks….they only reduce the likelihood of infestation. So frequent tick checks are really important.
  • Create strong vitality and resilience in your dog or cat by feeding a species-appropriate diet. Parasites are attracted to weaker animals. By enhancing your pet’s vitality, you can help her avoid the ill effects of a tick borne disease.

Preventing Intestinal Parasites

  • Puppies and kittens can get intestinal parasites from an infected mother – either across the placenta or from their mother’s milk.
  • Beyond that, most pets acquire intestinal worms by eating infected poop. So the best way to prevent infection is to make sure your pet’s environment is clean and ‘feces-free.’ Pick up your pet’s poop and make sure she doesn’t have access to infective feces from wild or stray animals around your property or anywhere else outdoors.
  • Whipworm eggs in the environment are extremely resilient and resistant to most cleaning methods and freezing temperatures as well. They can be dried out with strong agents like agricultural lime, but the best way to decontaminate a whipworm-infested area is to replace the soil with new soil or another substrate.
  • Keep your pet’s GI tract in good shape and resistant to parasites by feeding a balanced, species-appropriate diet. I also recommend either periodic or regular probiotic supplementation to insure a good balance of healthy bacteria in your pet’s colon, as well as a good quality pet digestive enzyme.
  • Have your vet check a sample of your pet’s stool twice a year for GI parasites.

What You Need to Know About Heartworm Disease Prevention

According to heartworm preventive dosing maps, there are only a few areas of the U.S. where dosing your dog with 9 months to year-round heartworm medicine might be advisable. Those locations are in Texas and Florida, and a few other spots along the Gulf coast. The rest of the country runs high exposure risk at from 3 to 7 months. The majority of states are at 6 months or less.

Preventives don’t actually stop your dog from getting heartworms. What these chemicals do is kill off the worm larvae at the microfilaria stage. These products are insecticides designed to kill heartworm larvae inside your pet. As such, they have the potential for short and long-term side effects damaging to your canine companion’s health.

To reduce your pet’s risk of exposure to heartworms, control mosquitoes:

  • Use a non-toxic insect barrier in your yard and around the outside of your home.
  • Don’t take your pet around standing water. Eliminate as much standing water as possible around your home and yard by cleaning your rain gutters regularly and aerating ornamental ponds and decorative water gardens.
  • Stay out of wet marshes and thickly wooded areas.
  • Keep your pet indoors during early morning and early evening hours when mosquitoes are thickest.
  • Make liberal use of a safe, effective pet pest repellent like my Natural Flea and Tick Defense.

If You MUST Use a Chemical Heartworm Preventive …

If you live in an area of the U.S. where mosquitoes are common and you know your pet’s risk of exposure to heartworm disease is significant, here are my recommendations for protecting your precious furry family member:

  • With guidance from a holistic vet, try using natural preventives like heartworm nosodes rather than chemicals. Make sure to do heartworm testing every 3 to 4 months (not annually) as natural heartworm preventives can’t guarantee your pet will never acquire the disease.
  • If your dog’s kidneys and liver are healthy, try using a chemical preventive at the lowest effective dosage. This could mean having the drug compounded if necessary for dogs weighing in at the low end of dosing instructions. Give the treatment at 6-week intervals rather than at 4 weeks, for the minimum number of months required during mosquito season.
  • Remember, heartworms live in your pet’s bloodstream, so natural GI (gastrointestinal) dewormers, such as diatomaceous earth, and anti-parasitic herbs (such as wormwood and garlic) are not effective at killing larvae in your pet’s bloodstream.
  • Avoid all-in-one chemical products claiming to get rid of every possible GI worm and external parasites as well. As an example, many heartworm preventives also contain dewormers for intestinal parasites. Remember – less is more. The goal is to use the least amount of chemical necessary that prevents heartworm. Adding other chemicals to the mix adds to the toxic load your pets’s body must contend with. Also avoid giving your pet a chemical flea/tick preventive during the same week.
  • Follow up a course of heartworm preventive pills with natural liver detox agents like milk thistle and SAMe, in consultation with your holistic vet.
  • Always have your vet do a heartworm test before beginning any preventive treatment. A protocol I put in place in my clinic last year is to run a SNAP 4Dx blood test every 6 months on dogs that spend a lot of time outdoors during warmer weather. The 4Dx tests for heartworm and tick borne diseases. Because parasites are becoming resistant to overused chemical preventives, the sooner you can identify infection in your pet, the sooner a protocol can be instituted to safely treat the infection with fewer long-term side effects.
  • ·         Source: Dr. Mercola

Evolution of Brain Imaging Instrumentation

Computed tomography (CT) and static magnetic resonance imaging (MRI) are now the most common imaging modalities used for anatomic evaluation of pathologic processes affecting the brain. By contrast, radionuclide-based methods, including planar imaging, single-photon emission computed tomography (SPECT), and positron emission tomography (PET), are the most widely used methods for evaluating brain function. SPECT and PET have been evolving for a longer time than CT and MRI and have made significant contributions to understanding brain function. The pioneering work on cerebral flow early in the last century laid the foundation of measurement with radioactive gases. This was initially performed with scintillation counters, which gave way to single, then multiple scintillation and multiprobe detectors. The invention of rectilinear scanners, MARK series, Anger cameras, and SPECT imaging further advanced nuclear medicine’s role in brain imaging. Measurement of regional cerebral blood flow by SPECT provides pathophysiologic information that directs patient management in a variety of central nervous disorders (CNS), with the greatest clinical impact found in cerebrovascular disease and seizure disorder. In the former, SPECT not only provides means of early detection and localization of acute strokes but can also direct thrombolysis and determine prognosis in the postcerebrovascular accident period. With respect to the latter, ictal SPECT can localize seizure foci so that patients with refractory disease can potentially undergo surgical resection of the affected area. In contrast to brain SPECT, brain PET images reflect regional cerebral metabolism. Because of neurovascular coupling, findings on SPECT and PET images are often comparable. PET, however, still has improved spatial resolution and is therefore more sensitive than SPECT, particularly in the evaluation of dementias. Brain PET instrumentation has greatly evolved from its infancy, when it was used in regional localization, to currently providing excellent resolution with imaging characteristics that can greatly impact clinical management. In addition, although ictal SPECT remains more sensitive than interictal PET for detection of seizure foci, the stringent conditions required for SPECT can be difficult to achieve, making interictal PET a very reasonable alternative. The clinical utility of PET and SPECT in neuropsychiatric and addictive disorders has not yet been defined, though a plethora of data exits. This arena of CNS disease has been the impetus for development of neurotransmitter-receptor-specific radioligands, which have already led to better understanding of dopaminergic, GABAergic, and serotonergic pathways. Another functional brain imaging technique that has gained broad acceptance since its invention in the early 1990s, is functional MRI, which indirectly measures CNS neuronal activity by evaluating oxygenation levels of cerebral vessels. Despite other recent related developments, such as MR spectroscopy, arterial spin labeling, and diffusion tensor imaging, nuclear medicine-based techniques remain clinically relevant and robust modalities, especially with the ever-expanding armamentarium of radiotracers and radioligands in conjunction with industry-driven improvements in image-analysis hardware and software.

source: science direct, seminars in nuclear medicine

The Promise and Pitfalls of Positron Emission Tomography and Single-Photon Emission Computed Tomography Molecular Imaging–Guided Radiation Therapy

External beam radiation therapy procedures have, until recently, been planned almost exclusively using anatomic imaging methods. Molecular imaging using hybrid positron emission tomography (PET)/computed tomography scanning or single-photon emission computed tomography (SPECT) imaging has provided new insights into the precise location of tumors (staging) and the extent and character of the biologically active tumor volume (BTV) and has provided differential response information during and after therapy. In addition to the commonly used radiotracer 18F-fluoro- 2-deoxyD-glucose (FDG), additional radiopharmaceuticals are being explored to image major physiological processes as well as tumor biological properties, such as hypoxia, proliferation, amino acid accumulation, apoptosis, and receptor expression, providing the potential to target or boost the radiation dose to a biologically relevant region within a tumor, such as the most hypoxic or most proliferative area. Imaging using SPECT agents has furthered the possibility of limiting dose to functional normal tissues. PET can also portray the distribution of particle therapy by displaying activated species in situ. With both PET and SPECT imaging, fundamental physical issues of limited spatial resolution relative to the biological process, partial volume effects for quantification of small volumes, image misregistration, motion, and edge delineation must be carefully considered and can differ by agent or the method applied. Molecular imaging–guided radiation therapy (MIGRT) is a rapidly evolving and promising area of investigation and clinical translation. As MIGRT evolves, evidence must continue to be gathered to support improved clinical outcomes using MIGRT versus purely anatomic approaches.

source: seminars in radiation onclogy