INSUFFICIENT AND ABSENT ACOUSTIC TEMPORAL BONE WINDOW - POTENTIAL ANDLIMITATIONS OF TRANSCRANIAL CONTRAST-ENHANCED COLOR-CODED SONOGRAPHY AND CONTRAST-ENHANCED POWER-BASED SONOGRAPHY

The aim of this study was to investigate the diagnostic potential of c ontrast-enhanced transcranial color-coded sonography (CE-TCCS) and con trast-enhanced transcranial power-based sonography (CE-TPS) in patient s with insufficient or absent acoustic bone windows (IABW). Due to tem poral bone thickness, the basal cerebral circulation could not be inso nated in 21 of 172 patients using unenhanced transcranial color-coded real-time sonography (TCCS) and transcranial power-based sonography. A dditional CE-TCCS and CE-TPS were performed after application of 400 m g/ml galactose microbubble suspension. In both modalities, the use of echo-contrast agents allowed visualisation of the first segment of the middle cerebral artery (MCA) in all patients. The Al segment of the a nterior cerebral artery (67% in CE-TCCS; 81% in CE-TPS), P1 segment of the posterior cerebral artery (71% in CF-TCCS; 76% in CF-TPS) and the basilar artery (48% in CE-TCCS; 67% in CE-TPS) were depictable in the majority of the examinations. The M3 (5% in CE-TCCS; 33% in CE-TPS; p < 0.05), P2 (24% in CE-TCCS; 71% in CE-TPS; p < 0.005), P3 segments ( 0% in CE-TCCS; 43% in CE-TPS; p < 0.005) and the posterior communicati ng artery (5% in CE-TCCS; 33% in CE-TPS; p < 0.05) were detected in a significantly greater proportion of subjects using power Doppler. In c onclusion, CE-TCCS and CE-TPS appear to be sensitive ultrasonic tools that provide reliable data regarding the basal cerebral circulation in patients with IABW. Furthermore, CE-TPS offers advantages over CE-TSS C in the identification of small-caliber arteries and vessels that run at unfavorable angels to the ultrasound beam. Both methods can overco me hyperostosis of the skull that is a major hindrance in transcranial ultrasonography, and may be helpful in the diagnosis of occlusive dis eases of intracranial vessels. (C) 1997 World Federation for Ultrasoun d in Medicine & Biology.