Ultrasound and the developing central nervous system

The potential risk of ultrasonography resulting in adverse biologic effects is particularly important in neurosonographic applications of diagnostic ultrasound in medicine. Key issues relate to the likelihood of producing bioeffects from the level of acoustic output emitted from modern diagnostically powerful ultrasound equipment. Important elements in the assessment of risk include the sensitivity of the tissue structures under examination, the standards of practice in clinical use and the presence of biologic effects identified from laboratory experimentation or from human studies. The World Federation for Ultrasound in Medicine and Biology continues to support activities related to evaluating bioeffects and safety of ultrasound. This paper includes extracts of some of the presentations given during the latest safety meeting, a mini-symposium on "ultrasound and the developing fetal central nervous system" held in conjunction with the WFUMB Congress in May 2000. The speakers covered topics ranging from physics of estimating heating from ultrasound equipment in clinical use to actual measurement of ultrasound-induced intracranial temperature increases in animal fetuses. Finally, some practical scanning strategies were proposed to minimise risk of adverse outcome in various clinical neurosonographic practices.