Three-dimensional transcranial color-coded sonography of cerebral aneurysms.
OBJECTIVE
The role of 2-dimensional transcranial color-coded sonography (2D-TCCS) as a diagnostic tool in cases of vascular alteration is unquestioned. The skill of the operator, however, may be responsible for some intertrial variability. The clinical value of a new, workstation-based, 3D reconstruction system for TCCS was evaluated in patients with intracranial aneurysms.


METHODS
Thirty patients with 30 intracranial aneurysms were investigated (8 men, 22 women; mean+/-SD age 54+/-17 years). The TCCS examinations were performed with a 2-MHz probe using the power mode. The 3D system (3D-Echotech, Germany) consisted of an electromagnet, which induced a low-intensity magnetic field near the head of the patient. A magnetic position sensor was attached to the ultrasound probe and transmitted the spatial orientation of the probe to a workstation, which also received the corresponding 2D-images from the video-port of the duplex machine. The echo contrast enhancer D-galactose (Levovist, Schering, Germany) was used in all patients to improve the signal-to-noise ratio. All patients underwent presurgical digital subtraction angiography (DSA) to demonstrate the aneurysm.


RESULTS
Twenty-nine of 30 angiographically proven intracranial aneurysms (97%) were detected by 3D-TCCS. The aneurysmal diameter estimated by DSA ranged from 3 to 16 mm (mean 7. 2+/-3.6 mm). A comparison of the 3 main diameters of each aneurysm revealed a correlation coefficient of 0.95 between DSA and 3D-TCCS. The 3D determination of the aneurysmal size by 2 experienced sonographers correlated with 0.96.


CONCLUSIONS
3D-TCCS is a new, noninvasive method to investigate intracranial aneurysms. The differentiation between artifacts and true changes of the vessel anatomy is much easier in 3D-TCCS than in conventional 2D-TCCS. The new method yields an excellent correlation with the gold standard, DSA. Because the same 3D-TCCS data can be postprocessed by different investigators, it may be possible to improve reproducibility and increase the objectivity of transcranial color-coded duplex sonography.
Klötzsch
C
C
Department of Neurology, Universitätsklinikum der Rheinisch-Westfälischen Technischen Hochschule, Aachen, Germany. CKloetzsch@t-online.de
Bozzato
A
A
Lammers
G
G
Mull
M
M
Lennartz
B
B
Noth
J
J
D015901:Angiography, Digital Subtraction; D016477:Artifacts; D003199:Computer Systems; D003287:Contrast Media; D055590:Electromagnetic Phenomena / Q000295:instrumentation; D005260:Female; D005690:Galactose; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation / Q000379:methods; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011134:Polysaccharides; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D018615:Ultrasonography, Doppler, Color / Q000295:instrumentation / Q000379:methods*; D017585:Ultrasonography, Doppler, Transcranial / Q000295:instrumentation / Q000379:methods*; D014741:Video Recording
D003287:Contrast Media; D011134:Polysaccharides; C059891:SHU 508; D005690:Galactose