some radiology for pediatricians

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Ren_Yumi
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some radiology for pediatricians

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September 10, 2007 — The American Academy of Pediatrics has issued a report to help healthcare providers in their decision making about the use of computed tomographic (CT) scans used for diagnostic tests for children and to help them lead discussions about these risks. The report, which is intended to aid in decision making and discussions with the healthcare team, patients, and families, is published in the September issue of Pediatrics.

"Imaging studies that use ionizing radiation are an essential tool for the evaluation of many disorders of childhood. Ionizing radiation is used in radiography, fluoroscopy, angiography, and computed tomography scanning," write Alan S. Brody, MD, and colleagues from the American Academy of Pediatrics Section on Radiology. "Computed tomography is of particular interest because of its relatively high radiation dose and wide use. Consensus statements on radiation risk suggest that it is reasonable to act on the assumption that low-level radiation may have a small risk of causing cancer."

By minimizing radiation doses to the extent possible and by performing CT scanning only when necessary, the medical community should attempt to decrease radiation exposure associated with CT scans. Consensus opinion suggests that the benefits of CT scanning, when performed for a valid indication, far outweigh the risks.

Healthcare providers in pediatrics play important roles in deciding when CT scanning is indicated and in discussing the associated risks with patients (when age-appropriate) and their families. Radiologists should be consulted to develop imaging strategies, and they should design specific protocols with scanning techniques optimized for pediatric patients. Families and patients should be encouraged to ask questions about the risks and benefits of CT scanning.

Exposure to high doses of ionizing radiation has been shown to increase the risk for cancer, and recent reports have highlighted the potential risk for cancer associated with the lower radiation exposure inherent in CT examinations. Although these reports have aroused concerns in pediatricians, patients, and families, literature review suggests widely differing opinions regarding the cancer risk associated with diagnostic imaging studies. Despite the variety of statements on ionizing-radiation risk in the literature, all seem to agree that the estimated risk from a CT scan is far less than the likely benefit to the patient for indicated examinations.

In terms of radiation dose, a head CT is equivalent to 200 chest x-rays, a chest CT to 150 chest x-rays, and an abdominal CT to 250 chest x-rays.

The following specific information is offered as a basis to underlie discussions of CT examinations and risks:

Radiation is a necessary component of a CT examination.


CT scanning is associated with low-level radiation exposure.


The cause-and-effect relationship between low-level radiation, such as that associated with CT scanning and cancer is still unclear. Expert consensus panels that have reviewed this issue have suggested that there is a small risk for cancer that increases with increasing radiation exposure.


Because no direct connection between CT scanning and subsequent development of cancer has yet been shown, the risks from CT scans must be estimated. These estimates vary according to the information underlying them.


The amount of radiation exposure associated with a CT examination depends on the protocols and equipment settings used, as well as on other factors.


As an overall rule, CT examinations performed properly in children should expose a child to a much lower radiation dose than that for the same procedure performed on an adult.


There is clinically recognized and documented potential benefit from an indicated CT examination, which greatly exceeds the potential cancer risk.


The as low as reasonably achievable (ALARA) principle states that radiologists are CT specialists trained to use the least amount of radiation necessary.
"There is wide agreement that the benefits of an indicated CT scan far outweigh the risks," the authors conclude. "It is the responsibility of those health care professionals who use CT scanning to ensure that each CT scan is indicated. It is the responsibility of radiology personnel to ensure that radiation risk is minimized by using the ALARA principle to determine the correct technique."

The American Academy of Pediatrics offers the following caveats: the recommendations in this report do not indicate an exclusive course of treatment or serve as a standard of medical care, variations based on specific circumstances may be appropriate, and all recommendations automatically expire 5 years after publication unless reaffirmed, revised, or retired at or before that time.

Pediatrics. 2007;120:677-682.
_____________________________________________________

Clinical Context
Ionizing radiation, high-energy radiation that produces ionization in exposed tissues, has natural and manmade sources. One manmade source is medical radiation, including CT scans.

As reviewed by the Biological Effects of Ionizing Radiation Committee of the National Academy of Sciences, increasing doses of ionizing radiation are linked to increased risk for cancer. But the effect of lower level radiation exposure from CT scans on the risk for cancer is not known.

This clinical report summarizes opinions regarding the risk for cancer from CT radiation exposure and recommendations about the roles of pediatric healthcare providers and radiologists in ordering and performing CT studies in children.

Study Highlights
Ionizing radiation:
1 Gy, the absorption of 1 J of radiation energy by 1 kg of matter, equals 100 rad.
A sievert (Sv) is based on the dose and radiosensitivity of each exposed organ.
Average background radiation from natural and manmade sources is 3 mSv/year per person in the United States.
Possible radiation-related risk for cancer is different in children vs adults because of increased sensitivity of growing tissues and organs, possible long latency period, and smaller cross-sectional area.
Diagnostic imaging:
X-ray doses depend on patient's age and size, equipment settings and model, and duration of procedure.
CT scans provide radiation exposure disproportionate to its use.
CT scan indications and frequency of use are increasing.
CT scan techniques that vary in radiation exposure result in similar images; 5% to –90% reduction in adult dose was adequate for CT study in children.
CT scans use less than a 100-mSv dose of radiation.
Radiation doses from CT scans of chest (3 mSv), head (4 mSv), and abdomen (5 mSv) correlate to 150, 200, and 250 chest x-rays, respectively.
No studies have been done to directly link CT scans to cancer.
Expert panel reviews suggest a possible small risk for cancer from low-level radiation from imaging studies that increases with increasing radiation dose:
The Biological Effects of Ionizing Radiation Committee of the National Academy of Sciences in 2005.
The United Nations Subcommittee on Atomic Radiation in 2000.
The International Commission on Radiation Protection in 2005.
Only up to 12.5% of healthcare providers recognize a possible link between CT scanning and cancer.
75% of clinicians underestimated the amount of radiation dose of CT scans vs chest radiographs.
Radiation exposure can be decreased by using ALARA radiation doses and only when needed.
Recommended role of pediatric healthcare provider:
Discuss risks and benefits of CT scanning with patients and families.
Make decision after appropriate consultation with other providers and family.
Realize that 11% of CT scanning is in children.
Be aware of increased CT use for conditions including trauma, appendicitis, and renal calculi.
Provide radiology practice information to families on training and certification of radiology practice and clinicians as well as size- or age-based protocols for CT scanner settings.
Communicate with radiologist about appropriateness of CT scanning and alternative imaging studies.
Limit times or phases (number of passes) of CT scanning.
Recommended role of radiologist:
Perform only appropriate imaging studies.
Communicate with pediatric healthcare provider if questionable indication for CT imaging.
Create protocols for age-appropriate scanning techniques to use ALARA radiation doses.
Be able to provide information on CT protocols and risks to healthcare providers and families.
Keep up with current CT technology.
If CT scanning is indicated, the benefit is greater than the risk for cancer.
Pearls for Practice
Low-level radiation from CT studies might carry a small risk for cancer, but the risk is outweighed by the benefits of indicated CT studies in children.
In performing CT studies in children, pediatric healthcare providers and radiologists should be responsible for considering indications, discussing the risk with patients and families, and optimizing age-appropriate techniques.
Ren_Yumi
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Сообщение Ren_Yumi »

CLINICAL CONFERENCE
Some Pitfalls in Pediatric Radiology

http://pediatrics.aappublications.org/c ... /25/6/1077

CLINICAL CONFERENCE: Some Pitfalls in Pediatric Radiology
Harvey White, M.D.
Children’s Mcmorial Hospital, Chicago
Pediatrics 1960;25;1077-1082

Thorough familiarity with normal variations and insignificant anatomic deviations is essential to tile practice of clinical pediatrics.
Through constant observation and experience differentiation from disease becomes possible.
In radiology this same problem exists and is probably more significallt, as roentgenograms record only the situation as of a particular moment - an inherent weakness of the method. In radiology many standard procedures are established so that results may be duplicated and irogress of disease evaluated. Deviations from standard procedures often simulate disease. In addition to this pitfall, there are mans’ anatomic variations to plague the radiologist at the time of interpretation.

The following are examples of roentgenograms which have simulated disease but upon investigation proved to be normal.

1 . The gaseous pattern in the infant differs from the adult. Ordinarily, we are taught that gas in the small bowel suggests obstructive ileus. In the illfant under 2 years of age, gas in the small bowel is normal. After this age or after the child begins to walk the gas in the small bowel disappears and its presence then
assumes significance. Improved intra-abdominal circulation, better coordination of diaphragnlatic movements is responsible for greater absorption of gas in the small bowel after this age (Fig. 1).
Large amounts of air in the stomach are not necessarily due to obstruction. A very hungry baby will swallow huge amounts of air to a point of distending the abdomen. We know this occurs and is without significance, as we use this phenomenon for diagnostic pyelography.
In this procedure, the ravenously hungsy child is given a bottle of formula after the intravenous or intramuscular injection of contrast material is administered. The fasted child takes the bottle eagerly and swallows gross amounts of air. The stomach pushes the transverse colon down and the kidneys visualize well through the air-distended stomach. It is truly remarkable how large the stomach will distend with this method (Fig. 2).

2. Variations of kidney anatomy are many and confusing. One of the most baffling to interpret is the depressed kidney, as seen on the pyelogram. By use of presacral injection of air we have proved that a lobulated kidney can simulate a suprarenal mass (Fig. 3A and B).

3. The variable growth of the skeleton is forever suggesting disease. Symmetrical epiphyses will show different growth patterns and irregularities. The femoral head in young infants may have small radiolucent defects along the articular surface due to incomplete ossification.
The infants are asymptomatic and a repeat examination in a month will reveal complete ossification and is therefore of no significallce.

The acetabular angles in infants vary considerably.
Increase of acetabular index does not indicate dislocation or hypoplasia. Other more important roentgen signs must be present for the diagnosis of congenital dislocation of the hip.
Difference in size of the femoral heads of a given individual can also occur normally. Progressfilms show that they both eventually become the same size. No therapy is necessary (Fig. 4A and B).

The epiphiseal-metaphyseal junction in young children is a zone of active growth and therefore this zone is more dense than the surrounding bone. The line of increased density at the distal end of the metaphysis is normal and should not be confused with heavy metal poisoning.

Bowlegs in the past was frequently thought to be subsequent to rickets. Vitamin D-deficient rickets today is rare, yet frequently we see bowlegs in young children; usually the parents are also bowlegged. It also is surprising the degree of straightening that results as these children grow. All clinical studies are normal and no therapy is indicated (Fig. 5A and B).



4. The history of trauma at times unduly influences the interpretation of anatomic variants as significant effects of injury. A notable example of this is the cervical spine. In the normal child, if a lateral roentgellogram is taken in partial flexion the body of C2 appears to ride slightly forward on the body of CS. If a child injures himself in the region of the neck a torticoilis usually develops because of muscle spasm and as a result the head and neck are held in partial flexion. Roentgenograms taken in this position reveal an apparent slip of C2 on C3. With the history of trauma this is falsely interpreted as a dislocation. By gentle traction the head can be placed in position for proper examinatioll and this mistake can be avoided. As soon as the muscle spasm is relieved, roentgenograms always show normal position of the vertebrae (Fig. 6A and B).

Variations of the skull also may present difficulties. Trauma to the skull is very frequent in children and kllowledge of suture lines and vascular channels is essential in order to avoid embarrassing errors in diagnosis of fractures.

5. Probably one of the most frequent roentgenograms taken in a child is the chest and upper airways. It is therefore extremely impontant that position and technique become standardized; otherwise, serious disease will be diagnosed. Precise frontal and lateral views must be obtained in inspiration. The trachea buckles
easily on expiration, the heart becomes enlarged and the lungs appear cloudy. All are pitfalls for the unwary (Fig. 7).
Allowing a child to abnormally flex the head for roentgenograms of the retrophamyngeal space will increase this area to a point of suspecting a retropharvngeal abscess. The head must be in a neutral position during the examination (Fig. 8A and B).

6. One can never stop cautioning our colleagues about the thymus. This gland has many bizarre variations and always brings up the problem of differential diagnosis. It is extremely rare for the thymus to produce symptoms.
From wide experience we have recognized the many thymic variants and assume that an asymptomatic anterior mediastinal mass probably represents the thymus. At times extensive investigation may be necessary. The preceding examples are but a few of the many technical and anatomic variations that offer a challenge to the diagnostic acuity of both the pediatrician and the radiologist.
Последний раз редактировалось Ren_Yumi Пт сен 28, 2007 10:27 pm, всего редактировалось 5 раз.
Ren_Yumi
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Сообщение Ren_Yumi »

Статья вместе с картинками в pdf не грузится. Очень большая.
Ren_Yumi
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Сообщение Ren_Yumi »

A. Which of the following statements about CT studies and cancer risk is most accurate?
1. Studies show a link between CT scans and cancer risk
2. CT scans are contraindicated in children
3. If a CT study is indicated, the risk outweighs the benefit
4. If a CT study is indicated, the benefit outweighs the risk


B. As a pediatric healthcare provider, you are considering ordering a CT study to aid in a child's diagnosis. Which of the following is recommended?
1. Consultation with the radiologist
2. Use of CT imaging techniques that are used in adults
3. Discussion of the risks, but not benefits, to the patient and family
4. Discussion of the benefits, but not risks, to the patient and family
Ren_Yumi
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Сообщение Ren_Yumi »

C. What is your diagnosis:
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Ren_Yumi
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Сообщение Ren_Yumi »

D. What about this?
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Dr. Mom
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Сообщение Dr. Mom »

Ren_Yumi писал(а):C. What is your diagnosis:
Какая-то непроходимость.

Я как-то более знакома с детьми снаружи,чем с детьми изнутри, получается как в Маленьком Принце, только наоборот - там, чтобы понять, что слона проглотили пришкось как раз смотреть изнутри 8)
На предыдущие вопросы не отвечаю, ибо за них свои кредиты уже получила - было бы не честно
Алла
"Life is either a daring adventure, or nothing."
Dr. Mom
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Сообщение Dr. Mom »

Ren_Yumi писал(а):D. What about this?
Ой, задесь еще круче...
Ладно, пошли читать по слогам, Как там у Иры - "будь что будет"?
Так что остановите если где чего не так скажу...

неонатология ...
желудочного пузыря не видно, сверху под левой диафрагмой что-то "сидит"...
петли кишечника растянуты, огромная ампула прямой кишки...

Гиршпрунг?
Алла
"Life is either a daring adventure, or nothing."
Ren_Yumi
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Сообщение Ren_Yumi »

Гиршпрунг.
Alon
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Сообщение Alon »

c- "double-bubble" sign
Всего наилучшего, Алон
Ren_Yumi
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Сообщение Ren_Yumi »

C. Duodenal atresia.
Supine radiograph demonstrates gas in the stomach and markedly dilated duodenal bulb.
D. Hirschsprung disease. 3-day-oldfemale with failure to pass meconium.
AP supine abdominal radiograph. Gaseous distention of both small bowel and colon.
Ren_Yumi
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Сообщение Ren_Yumi »

E. What do you see?
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Alon
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Сообщение Alon »

Между прочим "double-bubble" sign бывает не только при дуоденальной атрезии, хотя это, конечно, основная причина.
Всего наилучшего, Алон
Ren_Yumi
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Сообщение Ren_Yumi »

Абсолютно верно. Но у этого ребёнка была дуоденалная атрезия.
dr.Ira
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Сообщение dr.Ira »

Ren_Yumi писал(а):E. What do you see?
Не...Я точно не знаю...Что-то "лишнее" в области проекции сердца... :?: :?: И легкие какие-то уж очень "темные"... :?: :?: И что это? Бронх-не бронх, тубус не может быть... :?: :?: Не...не знаю. Прошу у радиологов описание снимка!
Делай, что должен, и будь, что будет.
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