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Published on: September 25, 2016
Cerebral microembolization during pediatric scoliosis surgery: a transcranial doppler study
R A Rodriguez1, M Letts, J Jarvis
1Divisions of Orthopedic and Cardiovascular Surgery, Department of Surgery, Children's Hospital of Eastern Ontario, Ottawa, Canada. RRodriguez@ottawaheart.ca
Insights
Scoliosis surgery often causes minor cerebral microemboli, typically not affecting vision. However, some patients experience high microemboli counts, potentially linked to cardiac shunts, warranting further investigation into brain function impacts.
Area of Science:
- Neurology
- Cardiology
- Ophthalmology
Background:
- Scoliosis surgery carries risks, including potential cerebral microemboli.
- The relationship between microemboli and visual changes after scoliosis surgery requires clarification.
Purpose of the Study:
- To detect cerebral microemboli during scoliosis surgery using Transcranial Doppler.
- To investigate the association between microemboli and visual alterations in pediatric patients.
Main Methods:
- Utilized Transcranial Doppler to identify high-intensity transient signals (HITS) in middle cerebral arteries.
- Conducted ophthalmologic examinations to assess visual function.
- Performed echocardiography to identify cardiac anomalies, specifically right-to-left shunts.
Main Results:
- High-intensity transient signals (HITS) were detected in 92% of patients during scoliosis surgery.
- Most patients (11/13) had low HITS counts (<15), with no reported visual complications.
- Two patients exhibited unusually high HITS counts (63 and 265), associated with atrial right-to-left shunts.
Conclusions:
- Scoliosis surgery is commonly linked to low-count cerebral microemboli, which do not appear to impact postoperative visual function clinically.
- High rates of microemboli in some cases may indicate underlying right-to-left cardiac shunts.
- The neurological impact of these high microemboli counts necessitates further research.
Summary:
The goal of this study was to identify cerebral microemboli during scoliosis surgery and their potential relationship with visual alterations. Transcranial Doppler identified high-intensity transient signals (HITS) during surgery in both middle cerebral arteries, and ophthalmologic examination assessed their potential effects on the visual system. Thirteen children (age 13-17 years) undergoing surgery for scoliosis or kyphosis with spine curvature >45 degrees were studied. HITS were identified in 92%. Eleven patients had a total count of <15 HITS, but in the remaining two the count was unexpectedly high (63 and 265 HITS). Echocardiography in these two patients indicated the presence of an atrial right-to-left shunt. Uneventful preoperative and postoperative visual function was found in 11 patients. One patient had preoperative blindness and in another ophthalmologic complications developed not related to microembolization. Scoliosis surgery is frequently associated with low counts of cerebral microemboli. It appears that such low embolic 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 these signals on brain function remains to be investigated.
