Safety of diagnostic imaging in pregnancy. Part 1: X‐ray, nuclear medicine investigations, computed tomography and contrast media

Abstract

Key content:• The safety of diagnostic imaging in pregnancy is a real concern.• In general, X-rays and computed tomography scans are unlikely to cause deterministic effects in an individual pregnancy. • Apart from the adverse effect of iodine on the fetal thyroid gland, common nuclear medicine investigation procedures are unlikely to involve teratogenic fetal doses. • Iodinated agents should be avoided in pregnancy.• It is recommended that paramagnetic contrast agents used with magnetic resonance imaging are only considered in pregnancy if absolutely necessary. Learning objectives:• To understand the principles, diagnostic value and safety of various diagnostic modalities using ionised radiation, at different stages of pregnancy. • To choose the most appropriate imaging tool for various medical conditions in pregnancy.• To be able to counsel pregnant women and provide them with accurate information about the safety of various diagnostic imaging modalities. Ethical issues:• Physicians should carefully weigh the risks and benefits of any radiographic procedure and include the mother in the decision-making process whenever possible. Keywords angiography / fetal growth restriction / intravenous pyelography / ionising radiation / miscarriage / ventilation-perfusion lung scanningPlease cite this article as: Eskandar OS, Eckford SD, Watkinson T. Safety of diagnostic imaging in pregnancy. Part 1: X-ray, nuclear medicine investigations, computed tomography and contrast media.

Surgical causes of acute abdominal pain in pregnancy

“…The estimated fetal dose of radiation per examination is 2–7/10 4 milligray (mGy). A dose of up to 10 mGy has negligible risk to the developing pregnancy in any trimester and carries an increase in childhood cancer risk of 0.002% . The presence of air under the diaphragm suggests perforation of a viscus, with high sensitivity but low specificity.…”

“…The fetus is most susceptible to the teratogenic effects of ionising radiation during the period of organogenesis (between 5 and 15 weeks of gestation) . Even at these doses of radiation exposure, the risk to the fetus is small, but the risk of childhood cancer is increased by 0.1% and fatal adult cancers by 0.3% …”

“…A dose of up to 10 mGy has negligible risk to the developing pregnancy in any trimester and carries an increase in childhood cancer risk of 0.002%. 14 The presence of air under the diaphragm suggests perforation of a viscus, with high sensitivity but low specificity. If abdominal signs of peritonitis are present, more sensitive imaging such as MRI will be considered to make a definitive diagnosis.…”

“…19 Even at these doses of radiation exposure, the risk to the fetus is small, but the risk of childhood cancer is increased by 0.1% and fatal adult cancers by 0.3%. 14…”

Knowledge, attitude, practice of dental surgeons regarding dental radiographs in pregnant women in the city of Karachi

“…Theseionizing radiations emitting from these radiographs have biological damaging effects on the cell directly or indirectly and produces free radicals that causesdamage to DNA [2] . International Commission on Radiological Protection (ICRP) in 1977 proposed that pregnant women should undergo exposures of low doses and are accounted for their exposures [3] .…”