Abstract 21597: Poor Pontine Perfusion on 99m Tc ECD SPECT in the Early Post-Resuscitation Phase Predicts a Poor Neurological Outcome
Background: Neurological outcome in patients resuscitated from cardiac arrest is usually poor. To date there are few practical indicators that well predict neurological prognosis in the early post-resuscitation phase. Meanwhile, the critical area in the brain responsible for neurological outcome is not clear yet. We therefore employed 99mTc-ethylcysteinate dimer (ECD) brain perfusion scan to investigate the critical brain area that is of prognostic implications.
Methods: The patients resuscitated from cardiac arrest underwent 99mTc ECD brain perfusion imaging using a dual-head SPECT/CT scanner on day 2–3 and day 7–10 post-resuscitation. Dynamic images of the head and neck were obtained over a period of 5 min in anterior and posterior projections, and SPECT was carried out 20 min after tracer injection. Peak flow of the bilateral hemisphere was normalized to the soft tissue of the left shoulder. SPECT images were normalized with such that peak activity of the brain was 100%. All images were interpreted by two nuclear medicine physicians who were unaware of the patients' clinical data. The scoring system was divided into five points (0–4). The brain was divided into 9 distinct regions: cerebral and cerebellar cortex, basal ganglia and thalamus (right and left, respectively) and pons for subsequent analysis.
Results: A total of 13 patients (65.1 ± 15.8 years old) were enrolled. Ten received therapeutic hypothermia. Eight survived to hospital discharge and 3 had neurological recovery with cerebral performance categories score 1. No significant dynamic changes on brain perfusion were noted from day 2–3 to day 7–10. For those with compromised brain perfusion on day 2–3, none regained consciousness. In patients with neurological recovery, the 99mTc ECD SPECT of the pons was better than those without (1.5 ± 0.5 vs. 3.4 ± 0.7 points, P < 0.001). There was no significant difference in other areas. Preserved perfusion of the cerebral cortex did not predict a good neurological prognosis.
Conclusions: Poor pontine perfusion on 99mTc ECD SPECT early post-resuscitation predicts a poor neurological outcome while cerebral cortex is of little prognostic implications. These suggest that reticular formation rather than cerebral cortex is critical for neurological prognosis.
- © 2010 by American Heart Association, Inc.