Transcranial Color-Coded Real-Time Sonography in the Evaluation of Intracranial Neoplasms and Arteriovenous Malformations

Abstract

Transcranial color-coded real-time sonography (TCCS) was performed in 57 patients with primary intracranial brain tumors (n = 49) or arteriovenous malformations (n = 8) to evaluate its diagnostic potential. In 46 patients (81%), lesions could be identified employing this technique. In 7 patients, transcranial ultrasound examination was not feasible because of bone thickness; in the remaining 4 patients, the tumor was indistinguishable from adjacent brain tissue despite sufficient insonation, suggesting that these neoplasms are isoechogenic. The sonographic features of brain tumors were very similar: a hyperechogenic matrix of the lesion was interspersed by hypoechogenic pixels. Larger hypoechogenic areas (0.5-1 cm) gave evidence of tumor necrosis. Differences between the findings of TCCS and computed tomography concerning tumor size were found in 7 patients, in whom TCCS revealed an area of smaller extension within the corresponding hypodense area on the computed tomographic scan. Perifocal brain edema could not be detected by ultrasound examination. In 13 patients, a thin, hypoechogenic peritumoral halo was disclosed that did not correlate with perifocal brain edema identified by computed tomography and that may have been due to compression of adjacent parenchyma. In patients with arteriovenous malformations, TCCS permitted the identification of the main feeders, the nidus, and the draining venous system by color-coded depiction of intravascular blood flow. In conclusion, TCCS is an additional method for initial diagnosis and highly suitable for follow-up in tumor patients and provides valuable information about tissue characteristics and blood flow.

Power Transcranial Doppler Ultrasound in the Detection of Intracranial Aneurysms

“…The sensitivity per aneurysm in previous noncontrast TCDS studies has ranged from 0.40 18 in the only previous large prospective study (nϭ203) to 0.89 in a smaller study of 36 patients. 11 Several other small studies have also reported sensitivity in the range of 0.53 to 0.89, 7,9,12,19 although all were in populations with a high prevalence of aneurysms. The difference between sensitivity in the present study and that reported in the early small studies might be due to a number of factors.…”

“…7,9,11 The transnuchal and transorbital routes were not routinely used (some of the patients found these difficult to tolerate), and intravenous echo contrast was not used. Each major intracranial vessel segment was examined systematically with power and anglecorrected spectral Doppler ultrasound.…”

“…6 TCDS became available in the early 1990s, with successful identification of intracranial aneurysms soon reported. 7,8 Ultrasound has the advantage of lower capital cost and greater mobility than IADSA, CTA, or MRA; additionally, there are no contraindications and no exposure to ionizing radiation. A more recent technological development of color Doppler termed color Doppler energy or "power Doppler" offers significantly greater sensitivity to flowing blood than standard color flow imaging.…”

201 Intraoperative Cerebral Glioma Characterization With Contrast Enhanced Ultrasound

“…US obviates the need for high costs and specialized surgical instruments. However, although standard US B-mode imaging is excellent for tumor localization, little information is provided regarding microcirculation and perfusion dynamics, even when integrated with Doppler sonography [10][11][12][13].…”

Quantitative Evaluation of Contrast Enhanced Transcranial Doppler Signal using Galactose Based Echo-Contrast Agent in Dogs

“…TCD can be used to confirm changes in cerebral hemodynamics [5] and has been commonly accepted as a method for evaluation of intracranial arterial stenoses or occlusions and arterial vasospasm after subarachnoid hemorrhage [1,30]. More recently, ultrasonic improvements have led to evaluation for morphologic imaging of the vessels by color-coded real-time sonography [4]. Preliminary reports suggest that TCD readings in the middle cerebral artery (MCA) also may correlate with intracranial pressure (ICP) elevation in patients with severe brain edema and brain death after head injury, and in hydrocephalic infants [13,18,31].…”