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 u ltrasound in medicine. Key issues relate to the likelihood of producing bio effects from the level of acoustic output emitted from modern diagnosticall y powerful ultrasound equipment. Important elements in the assessment of ri sk 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 act ivities related to evaluating bioeffects and safety of ultrasound. This pap er includes extracts of some of the presentations given during the latest s afety meeting, a mini-symposium on "ultrasound and the developing fetal cen tral nervous system" held in conjunction with the WFUMB Congress in May 200 0. The speakers covered topics ranging from physics of estimating heating f rom ultrasound equipment in clinical use to actual measurement of ultrasoun d-induced intracranial temperature increases in animal fetuses. Finally, so me practical scanning strategies were proposed to minimise risk of adverse outcome in various clinical neurosonographic practices.