HIGH-FREQUENCY DOPPLER ULTRASOUND EXAMINATION OF BLOOD-FLOW IN THE ANTERIOR SEGMENT OF THE EYE

PURPOSE: To show that extending Doppler imaging into the high frequenc y domain could allow detection and characterization of blood flow in s mall arterioles and capillaries. METHODS: A 40-MHz continuous wave Dop pler system and a 60-MHz pulsed-wave Doppler system were constructed, tested, and used to examine the ciliary body region in two normal volu nteers. RESULTS: Ciliary body circulation in the region of the great c ircle of the iris, which is undetectable by conventional 7.5-MHz duple x Doppler, was consistently and reproducibly detectable by high-freque ncy (40 MHz and 60 MHz) Doppler systems. CONCLUSION: High-frequency Do ppler imaging may provide a unique new tool for the characterization a nd assessment of anterior segment ocular blood flow. (Am J Ophthalmol 1998;126: 597-600, (C) 1998 by Elsevier Science Inc. All rights reserv ed.).