The Value Of SPECT Cerebral Blood Flow Of Hydrocephalus Patients Before And After Ventriculoperitoneal Shunt Operation

Objective: to understand the changes of regional cerebral blood flowbefore and after ventriculoperitoneal shunt operation, and to investigate thevalue of single photon emission computed tomography （SPECT） onhydrocephalus patients before and after ventriculoperitoneal shunt operation.Methods:114hydrocephalus patients were selected who were diagnosed bycomputed tomography （CT）and it was necessary for them to acceptventriculoperitoneal shunt operations according to clinical and imagingmanifestations.2Preparations for SPECT brain perfusion examination at least one daybefore the operation. Tracer agent:99mTc-ECD. Taking Potassium perchlorate400mg orally before intravenous injection of99mTc-ECD, in order to closethe thyroid, ventricle choroid plex and nasal mucosal and to minimize thedetection error caused by these organizations’ uptake and secretion of^99mTc-ECD, and then patient should keep quiet and relaxed as far as possible.30⁶0min later,^99mTc-ECD was injected intravenously, and maintained thestate before for about10min.3SPECT cerebral blood perfusion examination: let patient lie onexamining bed, with his or her head in the right position, keeping the OM lineperpendicular to the ground, facing above, and maintaining symmetrical andfixed. Applicat SPECT imaging device and low energy high resolutioncollimator, with collimator peak140keV and window width20%. Applicat theCRC-15R radioactivity detector to receive radiation signals, which weretransmitted to data and imaging to the computing platform. About30min laterimages were reconstructed by computer processor.4Ventriculoperitoneal shunt operation: According to CT or MRI manifestations, as well as the intracranial pressure, we selected the appropriatetube for ventriculoperitoneal shunt operation. We took routine care andtreatment, close observation of clinical manifestations and prevention of avariety of postoperative complications.5SPECT cerebral blood perfusion examination review: a week after theoperation we took SPECT cerebral blood perfusion examination review; Stepswere the same as before.6. Data analysis: semi-quantitative analysis was applicated to comparethe two imaging results before and after shunt operation. We selected ROI（regional of interest） three times manually refer to the computer processorwhich can select ROI automatically and then we get the average. ROIradioactivity/contralateral ROI radioactivity is RI （Regional Index）.According to the image performance and RI, perfusion disorders fall intoperfusion ischemia （RI <0.50）; perfusion reduction （RI>0.50but <0.90）;hyperperfusion （RI>1.10）. Record RI of14patients with perfusion reductionas RI1and RI2before and after shunt operation; record RI of8patients withobvious perfusion ischemia as RI3and RI4before and after shunt operation.7.Statistical analysis: the two pairs of data were statistically analyzed with thepaired t test.Results:1Of the14cases of hydrocephalus patients, there were5males and9females aged17to59years old with average age:36.9±12.8years old.Hydrocephalus with skull defects4cases, hydrocephalus after hypertensiveintraventricular hemorrhage3cases, hydrocephalus after subarachnoidhemorrhage5cases, idiopathic hydrocephalus2cases. The main clinicalmanifestations were headache and vomiting, and different neurologicalmanifestations such as hemiplegia, aphasia, ataxia, and mental disorders indifferent patients.214cases of patients were diagnosed with head CT. The CT diagnosticcriteria: lateral ventricle diameter/biparietal diameter=V/BP>0.26meanshydrocephalus, in which V/BP lies in0.26to0.40means mild type hydrocephalus;0.41to0.60means mid type hydrocephalus;0.61to0.90means severe hydrocephalus; and0.91to1.0means very severehydrocephalus. In accordance with these diagnostic criteria, the14patientscontained mild type2cases, mid type8cases, and sever type4cases.3The frequency of group perfusion reduction N=14, the averages of RI1and RI2are respectively0.6850±0.04637and0.7857±0.05932. There arestatistically significant difference between RI1and RI2（t=11.874P=0.000<0.01）. The frequency of group perfusion ischemia N=8, the averagesof RI1and RI2are respectively0.3375±0.05545�'�0.3325±0.06251. Thereare not statistically significant difference between RI3and RI4（t=0.764P=0.470>0.05）Conclusion: SPECT cerebral blood flow perfusion imaging as asecondary means of detection in the diagnosis and treatment of hydrocephalus,particularly provides changes in cerebral blood flow and brain function on thebasis of the CT or MRI morphological changes. The comparison of cerebralblood flow between before and after ventriculoperitoneal shunt operationshows that the blood perfusion in regional of perfusion reduction can besignificantly improved, in regional of perfusion ischemia can not be improvedideally.