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Basic Considerations of
Radiation Safety and Barrier Protection
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Hand Protection from Radiation Exposure
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During specific procedures, interventional radiologists, pain service physicians,
and GI physicians may receive some of the highest doses of radiation of any medical
personnel. Chronic irradiation of the hands is a principal radiation safety concern
for any physician involved in the broad spectrum of high-dose fluoroscopically guided
interventional procedures.16
As previously stated, fluoroscopically guided interventional procedures differ from
other forms of radiation since medical personnel cannot move behind a shield and
must stay in the room when x-ray exposure occurs. Because of the manipulation needed
in these types of procedures, physicians' hands must be in close proximity to the
scanning plane. Despite the use of devices such as needle holders (which are designed
to reduce exposure to hands), many of these procedures are very complicated and
force the physician to place his or her hands directly in the radiation beam for
a limited amount of time. Even when direct exposure can be avoided, the level of
exposure due to scatter can be very high during interventional procedures.17
Radiation exposure to hands is often the most significant factor in terms of overall
radiation risk for physicians who perform the growing number of interventional procedures.18
Most surprising, hands are the part of the body for which interventional radiologists
are least likely to wear protective garments.7
Because exposure from fluoroscopy is not trivial, concern over radiation exposure
has convinced some physicians to wear sterile x-ray attenuating surgical gloves.
Wagner and Mulhern believe it is necessary to include protection from both forward-scattered
x-rays as well as secondary electrons.19 However, physicians should realize
that these gloves are not likely to protect hands if placed fully into the fluoroscopy
beam. When placed fully in the x-ray field, gloves add to the attenuation of the
beam. This reduces image brightness, producing a large amount of scatter radiation
from the gloves that irradiates the hand. Therefore, physicians must not be lured
into a false sense of security and mistakenly rely on gloves as their principal
means of protection during fluoroscopy.
If the physician's hand is exposed to the direct beam, the mean dose reaches 120
mSv per procedure. Thus, on the basis of the annual dose limit of 500 mSv for the
hands as set by ICRP, a physician could only perform four (4) CT fluoroscopyguided
procedures per year to remain within occupational exposure limits. Kato found that
by using a biopsy needle holder, allowing the physician to place his/her hands 4
cm from the direct beam, exposure would drop to 1.5 mSv per procedure, thus enabling
the physician to perform up to 330 procedures per year.20
Monitoring for physicians is both a short-and long-term process. Theoretically,
physicians should calculate the exposure incurred in various procedures performed.
Physicians should then determine the number of procedures he or she can perform
in one year, based on the cumulative occupational dose limits as determined by the
ICRP.
Protective hand gear can be relied on only to protect against radiation outside
the field of view of the equipment's automatic brightness control. Doublegloving
with conventional latex surgical gloves provides only 1% attenuation. Specialized
radiation protection gloves can reduce scattered radiation to the hands by as much
as 59% at 60 kVp. Again, it must be stressed to keep hands out of the beam as much
as possible. If the image of one's fingers or hands appears on the monitor, they
are being directly exposed. Hands should always be pulled back from the imaged area
unless physical control is required for patient care.
Today's radiation protection gloves are less bulky and can be used effectively under
surgical gloves for interventional procedures, diagnostic heart catheterizations,
coronary angioplasties, pain management, orthopedic surgery, urology, or in other
situations where exposure to radiation is high. These gloves shield hands from the
harmful exposure to scattered radiation and are powder-free to reduce any risk of
powder-related complications. Some manufacturers offer latex-free and/or lead-free
bismuth oxide attenuating specialty gloves. Per unit weight, bismuth oxide provides
approximately the same radiation protection as lead, but it has the clear advantage
of much lower toxicity*.
*Always check with the manufacturer for attenuating
capabilities and specific performance characteristics.
Radiation protection gloves can be disposed of in the same manner as surgical or
medical examination gloves if:
- There is a possibility of induced radioactivity or contamination with radioactive
isotopes. The EPA has developed toxicity characteristics to regulate wastes likely
to leach hazardous concentrations through a landfill into groundwater. Lead falls
under toxicity characteristic and must not leach more than 5mg/liter, according
to the 40 Code of Federal Regulations 261.24.
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There is no possibility of radioactive contamination. If burned, the bismuth oxide
radiation attenuation additive will become part of the small amount of ash that
forms when any medical glove is burned. If they are land- filled, they will degrade
along with any other gloves in the group and contribute micronutrients to the soil.
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