Objective: To investigate the relationship of CMs to the relevant perilesional WM tracts using HDFT and to characterize associated changes first qualitatively and then quantitatively, using our novel imaging measure, quantitative anisotropy (QA).
Methods: Imaging analysis was carried out, blinded to the clinical details. Contralateral WM tracts were used for comparison. Mean QA values were obtained for whole WM tracts. Qualitatively affected superior longitudinal fasciculus/arcuate fibers and corticospinal tracts were further analyzed, using mean QA values for the perilesional segments.
Results: Of 10 patients, HDFT assisted with the decision-making process and offering of surgical resection in two, lesion approach and removal in seven, and conservative management in one. Of 17 analyzed WM tracts, HDFT demonstrated partial disruption in two, complete disruption in two, combination of displacement and partial disruption in one, displacement only in seven, and no change in five. Qualitative changes correlated with clinical symptoms. Mean QA for the whole WM tracts were similar, with the exception of one case demonstrating complete disruption of two WM tracts. QA-based perilesional segment analysis was consistent with qualitative data in five assessed WM tracts.
Conclusion: HDFT illustrated the precise spatial relationship of CMs to multiple WM tracts in a three-dimensional fashion, optimizing surgical planning, and demonstrated associated disruption and/or displacement, with both occurring perilesionally. These changes were supported by our quantitative marker, which will need further validation.
From: Application of High Definition Fiber Tractography (HDFT) in Management of Supratentorial Cavernous Malformations: A Combined Qualitative and Quantitative Approach by Abhinav et al.