Atlas-Based Quantitative Diffusion-Weighted Mapping in Patients with Aneurysmal Subarachnoid Hemorrhage (P06.231)

OBJECTIVE: To determine the prognostic significance of regional differences in brain apparent diffusion coefficient (ADC) in the acute phase of aneurysmal subarachnoid hemorrhage (SAH). BACKGROUND: Parcellation of ADC maps demonstrates a regional pattern of diffusion restriction which has been associated with outcome following anoxic brain injury. We explored the value of this approach in patients with SAH. DESIGN/METHODS: Patients underwent diffusion weighted brain MRI within 30 days of SAH. Atlas coregistration was performed using large deformation diffeomorphic metric mapping (LDDMM), and mean ADC values (in 10-6 mm2/s) were calculated in 26 regions of interest. Primary endpoint was Glasgow Outcome Scale (GOS) at hospital discharge or at 30 days. RESULTS: We enrolled 59 patients: 43 women, mean age 51 years, median admission WFNS 3. Forty-two patients underwent aneurysm clipping, 14 had coiling. In patients who were non-comatose on admission (Glasgow Coma Scale >/= 9), ADC was significantly higher in the right hemisphere, right lobar grey matter and cerebellar white matter. Patients with unfavorable outcome (GOS 1,2 or 3) had significantly lower ADC than favorable outcome patients (GOS 4 or 5) in the following regions: right anterior limbic cortex (823 +/- 79 vs 910 +/- 159, p = 0.037), left corona radiata (816 +/- 92 vs 906 +/- 165, p = 0.039), left corpus callosum (973.5 +/- 124 vs 1114 +/- 242, p = 0.027), left basal ganglia (862 +/- 60 vs 951 +/- 161, p = 0.031), right basal ganglia (883 +/- 109 vs 1014 +/- 174, p = 0.006), and midbrain (867 +/- 136 vs 993 +/- 204, p = 0.023). CONCLUSIONS: Here, using clinically obtained MRI scans, we identified specific anatomical patterns of ADC which were linked with SAH severity and its short term outcome. These results underscore the value of atlas-based quantitative mapping in acute neurological injury. Disclosure: Dr. Kalanuria has nothing to disclose. Dr. Leigh has nothing to disclose. Dr. Sutter has nothing to disclose. Dr. Pendleton has nothing to disclose. Dr. Vaidya has nothing to disclose. Dr. Tamargo has nothing to disclose. Dr. Stevens has nothing to disclose.