Evaluation Of Acute Brain Injury And Intracranial Pressure Using Transcranial Two-dimensional And Color Doppler Ultrasonography

Objective1. To evaluate the intracranial structural and hemodynamic changes inpatients with cerebral vasospasm and intracranial hematoma after acute brain injury usingtranscranial two-dimensional and transcranial spectral Doppler and transcranial colorDoppler sonography (TCCS), and to provide a new method for evaluation of acute braininjury.2. To observe the hemodynamic changes of the middle cerebral artery (MCA) inpatients with varying degrees of the increase in intracranial pressure (ICP) using TCCS,and to provide new indices for non-invasive evaluation of ICP for clinic.Methods Ninety-three patients (79males and14females) who had emergentsurgery for hematoma or underwent contusion tissue evacuation plus bone-flapdecompression in our hospital from May2012to August2012were included. All patientshad no other severe organ injuries or cardiovascular diseases. The color Doppler ultrasonicdiagnostic apparatus HI VISION AVIUS, Hitachi, was used equipped with a5-1probe with the frequency of1.8~2.0MHz. The sterilized probe was gently placed on the temporalwindow or the site for craniectomy. After obtaining the optimal two-dimensional images,color Doppler flow imaging or color Doppler energy techniques was initiated to detect thecerebral Willis circle arteries. Based on the flow direction and the anatomical position ofthe vessels by CDFI, the respective Willis circle vessels were determined. Then spectralDoppler was initiated with the incident angle less than60°. The changes of the flowspectra of the anterior, middle and posterior cerebral arteries (ACA, MCA, PCA) wererecorded every0.3~0.5cm along the arteries. The systolic peak velocity (Vs), enddiastolic velocity (Vd), time-averaged maximal velocity (Vm), pulsatility index (PI) andresistant index (RI) were measured. ICP was read at real time from the bedside CODMANintracranial pressure monitor with the micro-probe of intracranial pressure monitor placedin the cerebral ventricles, inside or outside of the dura.Results1. Thirty-nine intracranial hematoma were detected in34patients.Eighteen of the hematoma were found in the operational field,10were in the contralateraloperation field that occurred later after the operation. The boundary of the hematoma wasclear immediately after the operation, but blurred12hours later. Three hematomas werehypoechoic with surrounding edema. Twenty-four hours later, the center of the hematomaswere much hypoechoic and even cystic. The detection rate of the hematoma was94%byTCCS.2. Cerebral vasospasm (CVS) was found in49patients out of the55patients ofsubarachnoid hemorrhage (89%). According to the Aaslid standard,38patients had mildspasm (78%),8moderate spasm (16%) and3severe spasm (6%). CDFI displayed mosaicflow in MCA and the spectral Doppler showed that that MCA peak flow velocity wasincreased with filled-in spectral window. The sensitivity of TCCS for detecting cerebralvascular spasm was89%.3. With the increase of ICP, MCA Doppler flow spectral changed regularly. In earlyperiod of ICP increasing, the resistance of MCA was very high. When the ICP exceededthe diastolic pressure, diastolic reverse blood flow was seen. When the ICP exceeded thesystolic pressure, systolic “dagger-like” spectrum was detected with no diastolic blood flow. MCA-Vs had no correlation with ICP, but Vd had a significantly negativecorrelation with ICP（R2=0.272）.PI and RI had significant positive correlation with ICP（R2=0.787，R2=0.814）. Nineteen patients were diagnosed as brain death where completeWillis circle structure was unable to display by CDFI. Among these patients, MCA bloodflow could only be seen in3patients, a weak venous blood flow signal was seen in2patients and no flow could be seen in another2patients There were19patients whosecondition got worse even after the operation. The MCA spectrum of these patients showeddecreased flow velocity and increased PI and RI. Eventually, brain death occurred.Conclusions1. TCCS could be a convenient, non-invasive and reproducible methodfor evaluation of intracranial structural and hemodynamic changes in patients with acutecerebral trauma. It could be used to locate and quantify the hematoma changes andmonitor the progress of the disease. It could also be used to guide the interventionaltreatment at bedside and evaluate the therapeutic effects.2. TCCS could accurately locate the major spasm intracranial vessels and quantifythe hemodynamic changes at real time and in series, and could be used to evaluate thetherapeutic effects. TCCS could also be used to exclude other vascular malformations, andthus to help for the differentiation diagnosis.3. MCA spectral morphology and flow parameter changed regularly with theincrease of ICP, and may provide a new and effective method for non-invasive evaluationof ICP at real time and in series. In addition, TCCS may provide extra information forclinical diagnosis of brain death by observing the middle cerebral art rial flow changes.