经颅彩色多普勒超声检查指南（Transcranial color doppler ultrasonography guide）

经颅彩色多普勒超声检查指南（Transcranial color doppler ultrasonography guide） 经颅彩色多普勒超声检查指南(Transcranial color doppler ultrasonography guide) The second chapter is the cranial color doppler ultrasound examination guide | author: webmaster | source: original | viewing: 207 times The purpose of, Transcranial color doppler ultrasound (Transcranial color p-code real time sonography, TCCS) is the use of low frequency probe, the beam through the adult skull acoustic window (temporal bone mountain, the foramen magnum, orbit, skull defect area) and according to the essence and intracranial vascular structure, inspection method of noninvasive evaluation of the vascular hemodynamics of the skull base. Ii. Indications 1. Cerebral arteriovenous malformation 2. Intracranial aneurysms 3. Carotid cavernous sinus fistula 4. Cerebral artery stenosis and occlusion 5. Moyamoya disease 6. Dural arteriovenous fistula Other cerebrovascular diseases. The hemodynamic information can be understood by color doppler ultrasonography in general. Iii. Taboos and limitations Adult skull bone is thicker, the ultrasonic attenuation is serious, the sound window is limited, there is a certain blind area, the forehead, the head, occipital lobe and cerebellum partial vascular disease show also more difficult. 4. Preparation before inspection 1, instruments, all types of color doppler ultrasound instrument can be used, the temporal window, pillow window check the frequency of the probe is 1.8 ~ 2.0 MHz, selection of instrument equipped with specialized transcranial conditions, general depth range of 100 ~ 140 mm. High frequency probe was used in the detection of the orbital window and the superficial part of the neck table. 2. Patients: there is no need for special preparation. The patient should be accompanied by the family members of the patient. The patient with cerebral hemorrhage will be accompanied by a clinical doctor. Check the technology 1. Examination site and method Children and adult sound Windows use the temporal, occipital, orbital and cranial defect areas. (1) the temporal window: patients with lateral position, probe into above zygomatic arch, the area of orbital outer edge to the front of the ear, generally 1 ~ 5 cm in front of the ear of temporal bone mountain range, but also to divide the area before, during and after 3 detection area, according to the temporal, temporal and temporal window before, generally young and middle-aged in the front window, rear window in the elderly. Probe and skull surface vertical, cross-sectional scan, showed typical midbrain horizontal section first, two-dimensional image flag is "heart-shaped" low echo structure, open color doppler, according to adjust the color scale and color gain to the appropriate signal to noise ratio, adjust the probe position and Angle at the same time, looking for vascular Willis ring color doppler image, using doppler energy function can make better vascular imaging, and then to sampling frequency spectrum doppler blood flow parameter measurement. The sound window can show the brain (MCA), the brain (ACA), the posterior (PCA) artery and the internal carotid artery (ICA) end. The P2 segment of ACA and PCA is blue blood flow image. ICA shows the cross-section of multiple segments, which is a circular blood flow image with an area of < 0.5 cm2. (2) pillow window: located in the occipital protuberance of 2 ~ 3 cm, open 2 cm area around a center line, client take a prone position or sitting position, head and neck forward bends, as far as possible outside the probe at promontory at the bottom of the concave part, through the foramen magnum, show low echo the medulla diagonal plane, slightly adjust the Angle and direction, Color doppler shows the vertebral artery (VA) and basilar artery (BA) on both sides of the "Y". The window mainly detects the VA and the BA near. Eye socket: located above the eye socket. Choose high frequency probe, and the small organ condition, subjects in the supine position, closed eyelids, place the probe light on the eyelid, beam alignment supraorbital fissure, clearly showed the ball after the triangle, the opening of a CDFI, adjust speed rod to the appropriate scope, according to the probe placement points before and after the orbital and orbital inclined window window, display of ophthalmic artery, vein, ICA siphon. The normal eye artery is red blood flow signal, which is the high resistance spectrum of peripheral blood tube. The normal intraocular vein is a blue blood flow image, which is a continuous continuous vein spectrum. (4) from the skull defect inspection, according to the defect parts to take appropriate position, after the probe light on defect, along the joint operation direction more probes, tend to display the whole picture of intracranial vascular, obtain hemodynamic information. 5. Contrast-enhanced ultrasound can obviously enhance transcranial color doppler blood flow signal energy and strength, make a significant reduction caused by a skull window of sound attenuation, and can clearly improve cerebrovascular disease ultrasound diagnostic accuracy. The enhanced color doppler technique can be used in diagnosis and differential diagnosis of cerebral aneurysms, cerebral arteriovenous malformations, intracranial artery stenosis and occlusion. 2. Measure blood flow parameters and normal values Color ultrasonography can hardly show the inner diameter of the anterior, middle and posterior arteries of the brain, only through the changes of color blood flow imaging, spectrum morphology and blood flow velocity parameters, and understanding the hemodynamic information of cerebral blood vessels. Normally, the curve of the normal flow of blood flow starts with a steep rise in the cardiac cycle, which is called the ascending branch, and the peak of the formation of the spectrum is the peak of the contraction peak (S1). After the peak decrease formation (slow slope degrees, about two-thirds in the decline of incisure where there is a clear downward, after the incisura decline again rise to form a clear small wave, called the D peak, rising between the starting point and incisure of systolic, cut down the mark to the next point of departure for diastolic rise in cardiac cycle. Some healthy people, especially young people, can see a dent in the systolic drop, followed by a slightly lower peak called pulsating wave (S2). Common observation parameters are: the sampling depth, beam Angle, maximum blood flow velocity Vmax flow velocity (peak), minimal blood flow velocity Vmin Vmean (), end-diastolic velocity, average velocity, resistance index (RI, PI pulsation index, etc. Table 1 is the normal blood flow parameter reference standard. Table 1 normal intracranial arterial blood flow parameters (plus or minus s) 6. Diagnostic criteria for common cerebrovascular diseases 1. Cerebral arteriovenous malformation (1) multi-faceted display of anomalous multicolored Mosaic blood signals in clumpy, reticular or other shapes. (2) the spectrum of the doppler flow spectrum, the direction and/or deviant overlap of the probe, the audio signal companion or not accompanied by the strong and weak, which is similar to the "machine room sample" noise. (3) the main blood supply arteries in high speed, low resistance spectrum venous drainage for pulsatile blood flow spectrum change (because most of the blood pressure by AVM lesions to the venous drainage side, sometimes difficult to sample and arterial spectrum identification). 2. Intracranial aneurysm (1) color doppler shows the arterial blood vessels in a circular or elliptical blood flow signal. (2) it was linked with normal arterial blood flow, and its internal red and blue blood flow images showed eddy current flow. (3) the tumor is unidirectional and the spectrum of turbulence is upward. 3. Carotid cavernous sinus fistula (1) there was a confetti abnormal blood flow signal in the lateral cavernous sinus. (2) doppler detection shows abnormal disturbance of blood flow spectrum, audible and coarse blood flow audio signals. (3) the veins in the eye were widened and the blood flow reversed to show the low-resistance arterial blood flow spectrum. 4. Intracranial vascular stenosis or occlusion (1) narrow blood flow in narrow areas, bright or "multicolored" in color, typical of "girdle"; The color blood flow signal was interrupted by the narrow contrast. The occlusion of the vessel, the sound window is good, and in the case of other vessels, the closed blood vessels are not. (2) the light stenosis only shows the relative increase of velocity, the distribution of colored blood flow bundles is basically normal; In the middle - severe narrow blood flow rate significantly increased, the confetti and the turbulent blood flow images appeared; The blood flow velocity is relatively low in the long period of extreme or narrow segment, the color blood flow signal has no obvious central bright band, no typical flow rate increases rapidly, and the blood flow spectrum is abnormal. 5. Smoke disease (1) it is found that either side of the ICA or the ACA, the MCA blood signal is completely gone, or there is a very low blood flow signal or a gradual increase in velocity. (2) when PCA was involved in the PCA, the PCA showed the same performance as ACA and MCA. If the PCA was not involved, the blood flow rate increased significantly and the resistance decreased. (3) extracranial ICA, CCA resistance increased, and the flow rate decreased. (4) the smoke blood vessels in the base of the skull show the signal of the blood stream, which shows the characteristics of low speed and low pulsating blood flow. 6. Dural arteriovenous fistula (1) color doppler showed abnormal irregular mass flow imaging in the mouth of fistula. (2) turbulent spectrum with multiple directions and high speed and low resistance. (3) the flow rate of blood supply artery was abnormal and the resistance index decreased significantly. The flow rate of the drainage vein was increased rapidly, and the blood flow frequency spectrum showed the change of the low-resistance arterial blood flow spectrum. (4) the velocity of external carotid artery, occipital artery and superficial temporal artery increased rapidly and the resistance index decreased. Vii. Operation precautions (1) cerebrovascular disease examination, the same location time should not be too long. (2) the sampling line and color doppler beam parallel as far as possible, sampling point < 45 ?. (3) sampling the blood flow spectra of the sampling points should be observed every 0.3 ~ 0.5 cm from each blood vessel. (4) the relative ratio of the eponymous artery should be noted in the measurement analysis. (5) note the differential diagnosis of cerebrovascular stenosis and cerebral vasospasm. Viii. Basic contents and requirements of the report The blood vessel color doppler ultrasonography report includes clinical brief, ultrasonic description and ultrasonic diagnosis, and the latter two must be content. All blood flow parameters of the ultrasonic description: describe the blood vessels (blood flow velocity and pulse index and resistance index, measuring Angle, etc.), at the description should include the presence of lesions (irregular flake blood flow imaging, etc.); Lesion range (unilateral or bilateral cerebral artery, basal artery, etc.); The severity of the lesion (the range of each lesion; the area of the abnormal blood flow; the stenosis, stenosis, etc.); Related hemodynamic change information (such as narrow, anterior and posterior bloodstream velocity; involvement of blood supply artery; blood vessel blood flow parameters in extracranial segment, etc.); Other information. : ultrasonic diagnosis for the diagnosis of cerebrovascular disease, some diseases can provide diagnostic information, including location information and qualitative information (such as the right internal carotid artery cavernous sinus fistula, left brain aneurysm, etc.), quantitative information (such as start period of moderate stenosis of right middle cerebral artery), etc. Some diseases can provide instructional information (such as tips on the left side of the brain arteriovenous malformation, participate in the blood supply of the left posterior cerebral artery), or descriptive information (higher the left posterior cerebral artery blood flow velocity, resistance significantly reduce, suggest further examination).