CT is the de facto standard for stroke diagnosis. But newer MRI techniques, such as diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI), are more accurate, the article said.

“While CT scans are currently the standard test used to diagnose stroke, the academy’s guideline found that MRI scans are better at detecting ischemic stroke damage compared to CT scans,” said lead guideline author Peter Schellinger, MD, of the Johannes Wesling Clinical Center in Minden, Germany. Schellinger was quoted in an academy news release.

Ischemic strokes (resulting from lack of blood flow to the brain rather than hemorrhage) constitute about 87 percent of all strokes. In the United States, stroke is the third-leading cause of death and the leading cause of permanent disability.

The new guideline resulted from a study in which a team of neurologists, neuroradiologists, and radiologists analyzed literature dating from 1966 to January 2008. They particularly cited a study that compared the accuracy of CT and DWI in 356 consecutive potential patients at a hospital emergency department over an 18-month period. Two neuroradiologists and two stroke neurologists, blinded to clinical information and CT-DWI pairings, interpreted the scans independently.

According to the article:

In the subset of 221 patients scanned within 12 hours of onset, the majority of readers correctly diagnosed acute ischemic stroke by MRI more often than by CT (94 vs. 22).

The study also found that MRI more accurately detected lesions from stroke and helped identify the severity of some types of stroke or diagnose other conditions with similar symptoms.

“This guideline gives doctors clear direction in using MRI first, ultimately helping people get an acute stroke diagnosis and treatment faster,” said Dr. Schellinger. “However, one situation in which CT may still be used first is when a person needs an emergency injection of drug therapy (also known as intravenous thrombolytic therapy) to break up blood clots, if MRI is not immediately available, to avoid delays in starting this treatment. MRI can be added later if more information is needed. Otherwise, MRI should be used first.”

Related seminar: National Diagnostic Imaging Symposium

Two radiology technicians have sued Bozeman Deaconess Hospital in Bozeman, Montana. They claim that, while working in a darkroom at the hospital, they were exposed to unsafe levels of X-ray film developing chemicals.

Court documents say one of the women began working at the hospital in 2000 and the other in 2007. Both women say that within a short time, they began experiencing fatigue, headaches, and other symptoms. In the court documents, they say they were exposed to “unhealthy and toxic levels of Glutaraldehyde and other harmful chemical gases associated with developing X-ray film.”

The documents claim that on May 20, 2009, maintenance workers discovered that the ventilation fan in the darkroom was not plugged in and had never operated. In the documents, the women say that because of the “dangerous chemicals” in the unventilated room, they suffered damages including “physical injuries, medical expenses, lost earning capacity, lost wages, pain and suffering, mental, physical and emotional distress, loss of established course of life, loss of household services and other injuries.”

According to the federal Occupational Health and Safety Administration (OSHA), glutaraldehyde is used in X-ray developing solutions as a hardening agent to shorten film drying time. The OSHA publication Best Practices for the Safe Use of Glutaraldehyde in Health Care says, “The most serious adverse health effect documented among employees exposed to glutaraldehyde vapor is occupational asthma, a chronic condition characterized by bronchial hyperresponsiveness.” There are no mandatory federal exposure limits, but the National Institute for Occupational Safety and Health recommends a maximum exposure limit of 0.2 parts per million.

The hospital responded: “Bozeman Deaconess Hospital voluntarily requested an on-site safety consultation in June 2009 by the Montana Occupational Safety and Health Bureau. The State of Montana’s representative reported that ‘[n]o hazards were found during the visit to Bozeman Deaconess Hospital’ in the area in question.”

The hospital said it would defend itself against the suit but declined to elaborate, citing its policy not to comment in detail regarding pending litigation.

Related seminar: The Business of Radiology

Not so fast, say researchers at Wake Forest University Baptist Medical Center. Instead, their new study suggests placing such patients in an observation unit, monitoring them carefully, and stress testing them with cardiac MRI—which, though highly accurate for people with chest pain, is not commonly used for such patients in emergency departments.

The study found that these procedures saved money (by reducing the number of hospital admissions and tests), allowed patients who turned out not to have serious problems to go home quickly, and still identified all patients who were indeed suffering serious cardiac events.

“Every year, millions of people in the United States visit the emergency department because they are experiencing chest pain,” said Chadwick D. Miller, MD, an assistant professor of emergency medicine at Wake Forest Baptist Medical Center and lead author of the study. He was quoted in a medical center news release.

“A lot of these people end up being admitted to the hospital unnecessarily. To be able to either provide patients with the reassurance that their chest pain isn’t related to a more serious cardiac problem and get them back home within a day, or to diagnose the cardiac problem more quickly and begin treatment, is really satisfying.”

Dr. Miller said nearly half of the 6 million people each year who visit U.S. emergency rooms with chest pain are categorized as “non-low risk” and as a result admitted to a hospital for testing and evaluation. That, he said, leads to over-triaging of patients because only a small fraction end up suffering a serious cardiac event.

“The over-triaging and working up of people who don’t ultimately have cardiac events leads to a lot of spending—about $10 billion a year,” he said. “That’s a big deal.”

Indeed. No wonder Dr. Miller sounds pumped up about the study results:

This is probably one of the studies I’m most excited about being involved with. We were able to reduce cost, not miss any cardiac events, and reduce hospital admissions at the same time.

The results of the study have been published online in the Annals of Emergency Medicine.

Next step: testing the idea at other medical centers and in a larger population than the 110 patients involved in this study. Stay tuned.

Related seminar: Cardiac Imaging (just released; latest techniques)

So conclude two researchers who undertook a systematic review of 19 prospective studies involving 6,438 patients. Shauna Runchey, MD, and Steven McGee, MD, both of the University of Washington Department of Medicine in Seattle, published their findings this month in the Journal of the American Medical Association.

Distinguishing between the two types of stroke can be crucial. If it’s ischemic (caused by an interruption in blood supply), then a blood clot is often the culprit, and immediate thrombolysis treatment can break up the clot and minimize damage. But if it’s caused by hemorrhage, then thrombolysis can make things worse.

The various studies looked at markers of hemorrhagic stroke. For example, the likelihood that the stroke was hemorrhagic increased 6.2-fold if the patient was in a coma, 5.0-fold if neck stiffness was present, 4.7-fold if there were seizures, 4.3-fold if diastolic blood pressure exceeded 110 mmHg, 3.0-fold if there was vomiting, 2.9-fold if there was a headache, and 2.6-fold if the patient lost consciousness.

The Siriraj score, which encompasses some of the above factors as well as others, such as the presence of diabetes, also helped distinguish the two types of stroke. Patients were 5.7-fold more likely to have hemorrhagic stroke if they had a score higher than 1 and 71% less likely if they had a score lower than -1. However, Drs. Runchey and McGee noted that about 20% of patients have scores between 1 and -1, which they termed “diagnostically unhelpful.”

One study found that clinicians’ overall impressions were as accurate as the Siriraj score in diagnosing hemorrhagic stroke.

However, Drs. Runchey and McGee say, “Neither the clinical impression of experienced clinicians nor the most accurate stroke score can improve the post-test probability of hemorrhage to greater than 50%.” They conclude:

While combinations of findings are more predictive than individual findings, diagnostic certainty requires neuroimaging.

Related seminar: State-of-the-Art Imaging and Interventional Radiology

So suggests new research from Hospital Notre Dame in Montreal, as presented this week at the Canadian Stroke Congress in Quebec City.

“This study tells us when younger people come in with a first stroke, they may already have signs of preexisting damage in their brains,” said lead investigator Alexandre Poppe, a neurologist at the hospital’s Cerebrovascular Disease Centre. “We should pay particular attention to those who do, because they are at higher risk of having a second stroke, and prevention efforts need to be greatly emphasized.”

Silent brain infarcts (SBI) are tiny strokes that are asymptomatic but can be detected by brain imaging. Even though the patient has no idea they are taking place, they still cause damage. Previous research has shown that they are commonly found to have occurred in older adults with acute ischemic stroke. In those older patients, SBI predict recurrent stroke and cognitive decline.

Dr. Poppe and his colleagues for the first time looked for SBI in younger patients: 168 stroke patients ages 18 through 50, all of whom underwent MRI after a first stroke. The researchers followed the patients for 27 months, during which 11 of the patients suffered another stroke.

Those for whom MRI found previous silent strokes were three times more likely to have another stroke than those without lesions from SBI.

“All young people with stroke should be scanned, preferably using MRI,” said Dr. Poppe. “Doing a CT scan alone is often insufficient to pick up the brain changes caused by covert brain infarcts. With an MRI, you can actually tell how old the lesions are. You can see if they occurred before the stroke.”

Stroke risk factors are increasing for all ages, said Antoine Hakim, MD, PhD, spokesman for the Canadian Stroke Network. “Stroke in the young is underappreciated,” said Dr. Hakim. “Ten percent of stroke patients are under 50.”

Dr. Hakim suggested that young people may be making themselves more vulnerable to stroke because of unhealthy eating and living habits, including overeating and lack of physical activity. “This may be accelerating the impact of risk factors, especially high blood pressure, which are now converging and have the potential to erase the progress we’ve made in treating heart disease and stroke over the last 50 years.”

Related seminar: Emergency Radiology

April is National Child Abuse Prevention Month, and recent work has determined how child abuse victims might be more easily and better identified. 

HealthImaging.com relates information from the April issue of Radiology and the study by Laura A. Drubach, MD, and her colleagues from the department of radiology at Children’s Hospital and Harvard Medical School in Boston. They compared baseline skeletal survey and 18F-NaF PET images  in 22 children under the age of two. The former procedure showed a total of 156 fractures among the patients, and the latter showed 200.

“PET had sensitivities of 85 percent for the detection of all fractures,” Dr. Drubach wrote. “[It had] 92 percent for the detection of thoracic fractures (ribs, sternum, clavicle and scapula), 93 percent for the detection of posterior rib fractures, and 67 percent for the detection of classic metaphysical lesions (CMLs).”

These numbers were opposed to the baseline skeletal survey sensitivities of 72 percent for all fracture detection, 68 percent for thoracic fractures, 73 percent for posterior rib fractures and 80 percent for CMLs.

Since the PET did not show as well for CMLs, other exams would still need to be done, but, also, since CMLs are “distinct injuries in infants, PET scanning shows promise as the sole global skeletal assessment tool in children older than 12 months.” And the “image contrast from the high tracer extraction with 18F-NaF PET, as well as the intrinsically high sensitivity and high spatial resolution of 18F-NaF PET technology, makes it an attractive choice for the evaluation of child abuse,” according to the article.

In a paper from emedicine, authors wrote that “skeletal injury is the most common form of [abuse] injury (excluding external soft tissue injuries). Fractures are documented in 11-55% of physically abused children. Injuries to the long bones are the result of a direct blow or, more commonly, a shear force. Shear force is generated by pulling and twisting the body or by vigorously shaking the torso with flailing of the upper and lower extremities.”

Related seminar: Emergency Radiology

It’s the process from harvest to heroin that more directly affects the US. About three months after the seeds are planted, the petals drop from their bulbous pods, which the farmer cuts in vertical, parallel slits, allowing the sap to ooze and eventually form a brownish-black gum. The poppy grower scrapes the gum, forms it into balls or loaf shapes, wraps them in leaves or plastic and sells them.

The buyer takes the raw opium to a clandestine refinery where it is mixed with lime and boiled in water. A morphine layer forms on top of the water, which is skimmed, “reheated with ammonia, filtered and boiled again until it is reduced to a brown paste. Poured into molds and dried in the sun, it is now morphine base” as described in an article from pbs.org. As such, it has been smoked for centuries, starting with the Dutch in the 1600s.

The next manufacturing tier, usually a black market enterprise, was accidentally discovered in 1874 by C.R. Wright, an English researcher who boiled morphine and acetic anhydride for several hours and produced impure diacetylmorphine. Still working in primitive conditions, current day heroin makers boil the two components and then add water and chloroform to aid in purification. They drain the mixture and add sodium carbonate so that the heroin becomes solid and falls to the bottom. They charcoal filter it, purify it with alcohol, heat it to lose the alcohol and further purify it with ether and hydrochloric acid to roll out the white powder. One ton of heroin thus results from about 10 tons of raw opium. The finished product is proudly branded by some producers, such as Burma’s Shan State, according to the article, with logos and fancy wrapping. 

Although most illegal poppies are grown in a 4,500 mile mountainous strip of southern Asia, planted fields were discovered last year in the middle of Oregon forests. Fifty percent of medical morphine and other painkillers comes from poppies legally grown in Australia, as reported by The BBC.

Related seminar: Emergency Radiology

• nuclear detonation
• biological aerosol attack with anthrax
• biological disease outbreak from pandemic influenza
• biological attack from pneumonic plague
• chemical attack from industrial chemicals
• chemical attack from chlorine tank explosion
• radiation dispersion attack
• explosive attack using improvised explosive devices

According to the article, radiologists may be called upon for everything from managing acute radiation exposure (in the event of a nuclear attack) to helping treat blast, thermal, and overcrowding injuries in the event of an explosion in, say, a crowded concert hall or sports complex.

These are findings that “every radiologist should know,” said Rahul Pawar, MD, who reviewed the article.

Read or listen to more expert reviews: Practical Reviews in Radiology

OVUS—short for on-venue ultrasound—is provided at the cross-country Nordic, speed skating, freestyle skiing, snowboarding, and ice hockey venues, explained Olympics imaging director Bruce Forster, MD, in an annoucement by the RSNA. A mobile OR with X-ray and ultrasound allows doctors to perform surgery at the Alpine site.

Working in on-site “polyclinics,”—the Olympics’ term for small hospitals—radiologists use a local area network (LAN) line to send ultrasound videos instantly to imaging centers.

Some 5,000 athletes are competing in the events this year. “These athletes have been training for these events their whole lives,” said Forster.  “Sometimes they injure themselves in a way that makes it uncertain whether they can continue. We wish to help coaches and athletes make that decision with as much data as possible.”

Related seminar: Sports Medicine Imaging

“We urge all of those in the radiology community to give what they can to help alleviate the humanitarian crisis that is unfolding in Haiti. The ACR recognizes both the immediate and longer term radiological needs in Haiti and we hope this fund will provide relief as the people of Haiti seek to recover from the devastation” said James H. Thrall, MD, chair of the ACR Board of Chancellors.

Much of the health care infrastructure in Haiti’s capital and largest city, Port-Au-Prince, was destroyed by the earthquake - including radiology equipment, supplies, teaching materials and other materials that help support day-to-day care. The Haiti Radiology Relief Fund will seek funding to provide radiological equipment, materials and supplies as well as fulfill volunteer opportunities to support radiology services in the country.

All contributions are tax deductible with contributions made before March 1, 2010 eligible for 2009 or 2010 tax returns.2 The ACR Foundation asks for contributions from radiologists, radiologic technologists and other ancillary health care personnel, radiology organizations, patients, radiology and non-radiology corporations, radiology practices, radiology business managers and other interested individuals.

You can donate to the Haiti Radiology Relief Fund, and see how much has been raised so far, on Facebook.

Related seminar: Emergency Radiology