Risks Associated with Low Doses of Radiation

Depending on the machine settings, the organ being studied typically receives a radiation dose in the range of 15 millisieverts (mSv) (in an adult) to 30 mSv (in a neonate) for a single CT scan, with an average of two to three CT scans per study. At these doses, as reviewed elsewhere, the most likely (though small) risk is for radiation-induced carcinogenesis.

Most of the quantitative information that we have regarding the risks of radiation-induced cancer comes from studies of survivors of the atomic bombs dropped on Japan in 1945. Data from cohorts of these survivors are generally used as the basis for predicting radiation-related risks in a population because the cohorts are large and have been intensively studied over a period of many decades, they were not selected for disease, all age groups are covered, and a substantial subcohort of about 25,000 survivors received radiation doses similar to those of concern here — that is, less than 50 mSv. Of course, the survivors of the atomic bombs were exposed to a fairly uniform dose of radiation throughout the body, whereas CT involves highly nonuniform exposure, but there is little evidence that the risks for a specific organ are substantially influenced by exposure of other organs to radiation.

There was a significant increase in the overall risk of cancer in the subgroup of atomic-bomb survivors who received low doses of radiation, ranging from 5 to 150 mSv; the mean dose in this subgroup was about 40 mSv, which approximates the relevant organ dose from a typical CT study involving two or three scans in an adult.

Although most of the quantitative estimates of the radiation-induced cancer risk are derived from analyses of atomic-bomb survivors, there are other supporting studies, including a recent large-scale study of 400,000 radiation workers in the nuclear industry who were exposed to an average dose of approximately 20 mSv (a typical organ dose from a single CT scan for an adult). A significant association was reported between the radiation dose and mortality from cancer in this cohort (with a significant increase in the risk of cancer among workers who received doses between 5 and 150 mSv); the risks were quantitatively consistent with those reported for atomic-bomb survivors.

The situation is even clearer for children, who are at greater risk than adults from a given dose of radiation , both because they are inherently more radiosensitive and because they have more remaining years of life during which a radiation-induced cancer could develop.

In summary, there is direct evidence from epidemiologic studies that the organ doses corresponding to a common CT study (two or three scans, resulting in a dose in the range of 30 to 90 mSv) result in an increased risk of cancer. The evidence is reasonably convincing for adults and very convincing for children.

Risks/Benefits of Medical laser

With proper use, lasers allow the surgeon to accomplish more complex tasks, reduce blood loss, decrease postoperative discomfort, reduce the chance of wound infection, and achieve better wound healing.

As with any type of surgery, laser surgery has potential risks. Risks of laser surgery include incomplete treatment of the problem, pain, infection, bleeding, scarring, and skin color changes.

Laser surgery uses non-ionizing radiation, so it does not have the same long-term risks as x-rays or other types of ionizing radiation.

FDA's Role in Medical Radiation

FDA works to reduce radiation doses to the public while preserving image quality for an accurate exam by

establishing performance standards for radiation-emitting products, recommending good practices, and conducting educational activities with health professionals, scientists, industry, and consumers to encourage the safe use of medical X-rays and minimize unnecessary exposures
working with professional groups and industry to develop international safety standards that build dose-reduction technologies into various procedures and types of radiological equipment
working with states to help them annually inspect mammography facilities, test mammography equipment (X-ray machines to help detect breast cancer), and ensure that facilities adhere to the Mammography Quality Standards Act, which establishes standards for radiation dose, personnel, equipment, and image quality
monitoring industry technological advances that reduce radiation doses. Equipment manufacturers have already incorporated several advances to decrease the dose in newer machines that perform CT, which is considered the gold standard for diagnosing many diseases but also contributes greatly to the collective radiation dose to the U.S. population.
participating in "Image Gently," a national initiative to educate parents and health care professionals about the special precautions required for children who get X-rays. (Children are more sensitive to medical X-ray radiation than adults.)

Symptoms of Radiation Induced Nerve Damage

When just the ends of nerves (the "periphery") are affected, this is called peripheral neuropathy. Damaged sensory nerves do not accurately "sense" heat, cold, pressure, pain and body position.   When these nerve endings are damaged, a burning sensation is often experienced. 

Damaged motor nerves do not accurately tell muscles to contract and move.  This is sometimes referred to as muscle/nerve damage.  In these situations, the motor nerve is damaged which can lead to the muscles being weak or non-responsive.  It can make the person off balance.  Situations like this can start a year after the treatment is stopped. Inability to walk is often reported. 

The nerve damage from radiation can cause facial drooping, loss of hearing, erectile dysfunction, infertility, and pain as well as mobility issues. It can also cause  'drop foot'...a leg became weaker so that it can only lifted and inch or so off the floor. 

Nerve damage can happen anywhere in the body and the types of problems will come from the nerves that are damaged.

7 Reasons Your Neighbors Have More Money Than You

by VINCENT KING · 183 COMMENTS

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You look out the window of your home each night after dinner, staring across the street at your neighbors. You long for the cars they drive, their weekly manicured lawns, and even the vacations they seem to take several times a year.

I often look out my window, too, staring at the gorgeous homes and cars wondering how they manage to pay for them. After all, we live in the same neighborhood, our kids go to the same schools, and their salaries aren’t that much more than ours.

There are several reasons our can neighbors afford so many of the things we would love to have, but could never fathom splurging on:

Source and read more : http://moneyning.com/life-style/7-reasons-your-neighbors-have-more-money-than-you/

Pediatric chest CT: patient specific dose and risk calculation

Risk-dosage relationship with patient age and size is feasible for effective planning and optimization of pediatric chest CT procedures.




Chest CT scans
The medical research study was conducted by Xiang Li, PhD, Ehsan Samei, PhD, W. Paul Segars, PhD, Gregory M. Sturgeon, BS, James G. Colsher, PhD and Donald P. Frush, MD from Department of Radiology, Duke University Medical Center, Durham, NC.

The study is available in online journal of Radiological Society of North America, and the research objective was to appraise cancer risks from pediatric CT scan and patient specific radiation dose, for evaluation of factors affecting dosage and risk, inclusive of CT scanning parameters, patient age and size etc.

HIPAA compliant, and approved by IRB (Institutional Review Board), about 30 patients (Age: 0-16 years) were selected with clinical CT data created recently through full body computer models. An approved Monte Carlo computational algorithms were utilized to evaluate organ dosage through eight CT chest protocols, staging clinically relevant combinations of bowtie filtration, collimation, pitch and optimal tube potential.

Organ dosage was utilized to ascertain effectual risk index and dosage; dosage and estimates of risk before/after normalized CT dose index were made to relate with patient age and size, along with effect of CT scanning parameters.

About the results, with increased chest diameter – normalized organ dose through with tube current modulation decreased in an exponential manner. Chest diameter was a strong predictor variable for dose than scan length/weight. Normalized by tube current modulation, CT dose index decreased in an exponential manner, with both chest age and diameter.

After normalization by dose length product – risk index and effectual dose were found free of tube potential, pitch and collimation.

Conclusion: The combined relation of risk and dosage with patient age and size can be utilized for patient specific dose and risk calculation, as they direct for effective planning and optimization of pediatric chest CT procedures.

TSA Scan at Airport: X-Ray Exposure and Cancer Risks

TSA Scan

The full-body scanners that are deployed in airports are considered now to be grave for regular flyers, of probable skin cancer, due to repeated radiation exposure.

Transportation Security Administration in USA has deployed full-body scanners in airports last year. Many opposed it stating privacy and health concerns due to radiation exposure, but TSA opined the radiation beam through the scanners are harmless, as of low frequency.

Flying exposes more to ionizing radiation, as a flyer is vulnerable more to cosmic rays at altitude elevation, in comparison to the scanners that put up about 1% or so.

Across 78 airports in the US have around 486 scanners being deployed so far, and about 1000 are believed to be deployed by 2011. There are 2 different types of full-body scanners put in use, generally, where each of the scanners produce out detailed outline of person on scan, to recognize out if they carry any lethal weapons or have hidden anything illegal/non-permissible under their clothes.

Millimeter-wave scanners used at airports emit low energy waves same like of a cell phone we use in every –day practice, where the scanners incarnate the reflected energy.

The backscatter X-Ray scanners, which are also used use low-dose ionized radiation similar to that used in diagnostic medical imaging procedures. In contradiction to X-Ray, where the disparity in the transmission of the beam through the human body is made to produce out images, the backscatter scanner detects out radiation emitted off of the person, and when the emitted out radiation go through the air, the energy gets deposited to the skin tissue, which can lead to serious skin cancers etc.  on prolonged exposure.

Unlike millimeter-wave scanners, the backscatter X-ray scanner uses ionizing radiation, and severe exposure can pose more dangers to the individuals. With low-dosage exposure only biological damage occurs, as the cell continuously repairs this damage endlessly to mend over the impairment.  On the other, moderate dosage can be bit harmful, as it transform the cells permanently, and could lead to grave cancers and other birth-associated deformities/irregularities.

In every other case of low, moderate or high-dose exposures, risk is always associated – if the individual is made to pass for prolonged usage. Though security is vital, but more than that health always take first priority. For elaborated article (Courtesy:Archives of Internal Medicine) we direct you to the following link: http://archinte.ama-assn.org/cgi/reprint/archinternmed.2011.105v1.pdf

CTA protocols for low dose Pediatric Imaging

For the safety of the pediatric cardiovascular and vascular patients wh o need the CTA for diagnostic purposes, low dose CTA is essential, says Jeffrey C. Hellinger, M.D., a pediatric imaging specialist at Stony Brook University Medical Center. Dr. Hellinger has also shared his views on the topic in the early online edition of Radiologic Clinics of North America.

Dr. Hellinger has developed CTA protocols and new measures that he has spoken about has balanced lower doses of radiation and clear diagnostic images when using CTA on infants and children. As Principal Author of “Pediatric  Computed Tomographic Angiography: Imaging the Cardiovascular System Gently,” Dr. Hellinger details the appropriate and safe use of non-invasive CTA, in the context of other potential cardiovascular imaging modalities, including radiography, echocardiography, vascular ultrasound, magnetic resonance imaging (MRI) and angiography (MRA), and invasive catheter angiography (CA).

“The use of any radiation in diagnostic methods carries a risk of causing cancer and of abnormal development, particularly in infants and children,” says Dr. Hellinger. “There is basically a medical necessity, if you are going to use  radiation in your imaging, to use the lowest possible amount,” he emphasizes.

“I think it’s a controversial topic as to how much radiation will lead to increased cancer risk over the lifetime of a patient,” he adds. “As physicians and imagers, with CT angiography, it is our goal to use the lowest possible radiation without compromising imaging quality. There a balance between how low you can go with the technology and rendering a diagnosis. If the radiation dose is too low and the image is poor, you have wasted the radiation.”

Dr. Hellinger and co-authors present their findings on low-dose pediatric CTA protocols and the needed ancillary protocols to achieve high image quality, emphasizing that using complementary “gentle” cardiovascular CT “can  enhance the diagnosis and management of the pediatric patient with cardiovascular disease. Given the intrinsic dependencies upon radiation, utilizing this modality in pediatric patients mandates a commitment to dose reduction strategies, striving for ALARA (As Lows As Reasonably Achievable) in each cardiovascular CT examination.”

For each patient, Dr. Hellinger writes, all the sectors surrounding cardiovascular CT should be reviewed. “The pediatric CTA protocols are uniquely designed to maximize the table speed, image at the lowest possible voltage, and use the  lowest possible weight-based tube current.”

Dr. Hellinger, who joined SBUMC around the June 2010 launch of Stony Brook Long Island Children’s Hospital, the only dedicated children’s hospital east of the Nassau/Queens border, developed an expertise in creating low dose radiation pediatric imaging protocols over the past four years. He built a cardiovascular imaging program in the Department of Radiology at The Children’s Hospital of Philadelphia (CHOP).

At SBUMC, Dr. Hellinger partners with Michael Poon, M.D, Director of the Advanced Cardiac Imaging Program and a world-renowned expert in cardiac CT and MRI. Central to their imaging diagnostic methods is SBUMC’s acquisition  earlier this year of a state-of-the art 320-detector row CT scanner, which provides physicians with accurate images of internal organs with a single rotation of the gantry, that results in lower doses of radiation while providing the best  imaging features possible.

ECRI Expanded Recommendations Regulating CT Radiation Dose

Computed Tomography (CT) dose is on ECRI Institute’s 2010 list of top 10 technology hazards. Recommendations for regulating CT radiation dose is thus, expanded by the Institute.

High CT radiation doses are being delivered to patients on a daily basis, putting them at an increased risk of developing cancer. Hence, keeping CT radiation dose in check is a high priority safety concern for hospitals. While increased levels of radiations may put patients at risk, diminishing the same, will affect the image quality that may result in incomplete examination or rescanning of the image. The process will expose the patients to even more radiation.

Practical esteem to balance between the degree of radiation are presented in a new guidance article, “CT Radiation Dose: Understanding and Controlling the Risks,” released by ECRI Institute, an independent, nonprofit organization that researches the best modes of care. This comprehensive Health Devices article expands on the recommendations about controlling CT radiation dose published in ECRI Institute’s 2010 Top 10 Technology Hazards list.

ECRI Institute emphasizes that the responsibility also lies with the facility itself, referring physicians, medical physicists, radiation technologists, and CT device manufacturers. The article includes sixteen practical recommendations that every facility should identify with, to help control radiation dose in CT.

The recommendations are set in 5 major sections:

1. protocol optimization,
2. prioritizing dose reduction,
3. patient selection,
4. the technician’s responsibilities,
5. quality assurance.

Dr.Keller, vice president, health technology evaluation and safety, ECRI Institute, considers the latest CT models are created with dose-saving technologies, but they may not be very affordable for many organizations. “In time, these technologies will become more widely installed,” says Keller. “Until then, there are a number of effective strategies every facility can implement to reduce dosage.The article also includes a dedicated section on dose-reduction technologies and the amount of dose savings they each achieve.

Conventional radiographic exam, and childhood cancer risk: Cohort study

Author: Janet

There is no increased childhood cancer risk, with very low dose radiation through diagnostic imaging, which is consistent with model calculations.

The study is available in American Journal of Roentgenology. The long-term consequences of diagnostic ionizing radiation exposure in childhood is slightly less known. Current evaluations are made with models obtained chiefly through research of survivors of atom bombs, people that vary from present-day patients in many aspects, and the preliminary research objective was to quantify risk amongst young patients through radiography exam.

In a German university hospital, cancer occurrence in children that underwent diagnostic x ray exposures during year 1976-2003 were assessed by the researchers. They reorganized case-by-case radiation dosage for each, and classified results by referral criteria groups for all cancers.

Through 78,527-patient cohort, in the duration of 1980-2006, about 68 cancer incidence cases were recognized, in the German childhood cancer registry: except for 25 other, 9 lymphoma, 28 leukemia, and 6 tumors of the central nervous system were found. For all the cancers, the standardized incidence ratio was 0.97; through multivariate poisson regression – dose response relationships were evaluated.

Even though cancer incidence risk varied by primary referral criterion for radiographic examination, for 5 patients with metabolic/endocrine disease, a positive dose response relationship was noted.

Conclusion: There was no heightened cancer risk amongst children/youth, with very low dose radiation through diagnostic imaging, which is consistent with model calculations. The increased usage of computed tomography justifies further studies to evaluate related cancer risk.

Low-dose over contrast-enhanced abdominal CT: for acute appendicitis, in young adults

The diagnostic performance of low-dose CT is comparable to standard dose CT, to characterize/analyze appendicitis in young adults.




Acute appendicitis_CT scan
The medical research study was conducted by So Yeon Kim, MD; Kyoung Ho Lee, MD, PhD; Kyuseok Kim, MD, PhD; Tae Yun Kim, MD, PhD; Hye Seung Lee, MD, PhD; Seung-sik Hwang, MD, PhD; Ki Jun Song, PhD; Heung Sik Kang, MD, PhD; Young Hoon Kim, MD, PhD and Joong Eui Rhee, MD, PhD from the Departments of Radiology, Emergency Medicine, Seoul National University, Korea; Department of Social and Preventive Medicine, Inha University School of Medicine, Incheon, Korea; and Department of Biostatistics, Yonsei University College of Medicine, Seoul, Korea.

Appendicitis is an inflammation/rubor of the vermiform/cecal appendix. The research objective was to equate standard and low radiation doses in intravenous, contrast-enhanced abdominal CT scan, for identification of acute appendicitis in young adults.

The study comprised about 257 patients, suspected of appendicitis that passed through CT with standard/low radiation dose; through with Wilcoxon rank-sum test, Freeman-Halton statistics, and ROC curve analysis the diagnostic performance of CT was recorded and equated by, for appendicitis.

Of 44 standard dose and 55 low radiation dose examinations, one of the abdominal radiologists made primary report, which served as final report; for residual examination, on-call radiologists were requested that submitted over primary reports, and the abdominal radiologists then put forward final reports.

About primary reports – standard and low dose CT groups did not considerably vary in regions under the receiver operating characteristic curve, specificity or sensitivity, for detection of appendicitis; no considerable deviation could be established amongst two groups in confidence level, when diagnosing/debarring appendicitis in preliminary reports; identical results were marked for the final reports. The dose groups even did not substantially vary in terms of subsequent: appendiceal visualization/image, distinctive characterization of appendiceal perforation, sensitivity for substitution method/diagnoses etc.

Conclusion: the diagnostic performance of low dose computed tomography to that of standard-dose CT is comparable, for characterization of appendicitis in young adults.

Warning Signs and Lights "Radiation Producing Machines and Devices"

All "analytical x-ray equipment" must have the following items:

1. A clearly visible label, near any switch energizing an x-ray tube, which bears the radiation symbol and the words: "Caution: This Equipment Produces X-rays When Energized. To Be Operated Only By Authorized Personnel."
2. A clearly visible label, near the x-ray tube housing, which bears the radiation symbol and the words: "Caution: High Intensity X-ray Beam."
3. A clearly visible fail-safe* warning light, near any switch energizing an x-ray tube, labeled with these words: "X-ray On."
4. A clearly visible fail-safe warning light in a conspicuous place near the x-ray tube which indicates when the x-ray tube is producing x-rays.

*As used for the purposes of Section 16, "fail-safe" means that all failures of warning and safety systems that can reasonably be anticipated will cause the equipment to fail in a mode such that personnel are safe from exposure to radiation.

Requirements for Enclosed Beam X-ray Systems

An enclosed beam system is a system in which all possible x-ray paths are fully enclosed so that any part of the body cannot enter the enclosure. In addition to the general requirements found in paragraph 2 above, the following requirements must be met:

a. Safety Devices

There must be:

• Enough interlocks to prevent the generation of x-rays or the emergence of the primary beam when any section of the enclosure is opened during routine operation, alignment or maintenance.
• A chamber or coupled chambers enclosing the radiation source, sample, detector and analyzing crystal, which cannot be entered by any part of the body during normal operation.
• A sample chamber closure with a fail-safe interlock so that no x-ray beam can enter an open sample chamber.

b. Dose Limits

The equipment must be so constructed that the dose rate due to leakage radiation at 5 cm from any accessible surface does not exceed 0.25 mrem/hour during normal operation.

Pregnant nuclear medical technician

• The regulatory gestational radiation dose limit to a declared pregnant worker is 500 mrem a
• Nuclear Regulatory Commission regulations and some Agreement State regulations state that average exposure to a declared pregnant worker should be maintained, if possible, to 50 mrem/month.
• The average whole-body radiation dose for a nuclear medical technician is 400-600 mrem/year (National Council on Radiation Protection & Measurements Report 124).

Pregnant magnetic resonance imaging (MRI) Technologist

There is no evidence in the scientific literature that a standard diagnostic MRI performed on a person who is pregnant will cause fetal biological effects. The literature suggests that the strength of the magnetic resonance (MR) field at diagnostic levels does not affect DNA synthesis, cell cycle, or proliferation kinetics in a fetus. The Food and Drug Administration (FDA) and other regulatory agencies have strict limits on MRI field strengths at diagnostic levels.

Radiation workers Rdiation limit per year

A radiation worker is allowed to receive up to 5000 mrem (5 rem) each year as a result of exposure received on the job. In most states, the radiation dose to a fetus of a declared pregnant worker (a radiation worker who has told the Radiation Safety Officer of her pregnancy) must be kept below 500 mrem (0.5 rem) during gestation. It is also important to note that low levels of ionizing radiation are not foreign to our bodies. Each year the average U.S. citizen receives an exposure of approximately 300 mrem (0.3 rem) from natural radiation sources. If you have concerns regarding the situation in your specific facility, you might try to contact your facility’s Radiation Safety Officer.