Cerebral microembolization during pediatric scoliosis surgery: A transcranial Doppler study

The goal of this study was to identify cerebral microemboli during scoliosi s surgery and their potential relationship with visual alterations. Transcr anial Doppler identified high-intensity transient signals CHITS) during sur gery in both middle cerebral arteries, and ophthalmologic examination asses sed their potential effects on the visual system. Thirteen children (age 13 -17 years) undergoing surgery for scoliosis or kyphosis with spine curvatur e > 45 degrees were studied. HITS were identified in 92%. Eleven patients h ad a total count of < 15 HITS, but in the remaining two the count was unexp ectedly high (63 and 265 HITS). Echocardiography in these two patients indi cated the presence of an atrial right-to-left shunt. Uneventful preoperativ e and postoperative visual function was found in 11 patients. One patient h ad preoperative blindness and in another ophthalmologic complications devel oped not related to microembolization. Scoliosis surgery is frequently asso ciated with low counts of cerebral microemboli. It appears that such low em bolic counts have no effects on postoperative visual function as determined clinically. Some patients may show high rates of microemboli, which may be related to the presence of right-to-left cardiac shunts. The impact of the se signals on brain function remains to be investigated.