More articles from FUNCTIONAL
- The Contribution of Common Surgically Implanted Hardware to Functional MR Imaging Artifacts
The authors calculated the BOLD-dependent MR imaging artifact impact arising from surgically implanted hardware through a retrospective analysis of fMRIs acquired from 2006–2014. Mean artifact volume associated with intracranial hardware was 4.3 cubic centimeters. The mean artifact volume from extracranial hardware in patients with cerebrovascular disease was 28.4 cubic centimeters. Artifacts had no-to-mild effects on clinical interpretability in all patients with intracranial implants. Extracranial hardware artifacts had no-to-moderate impact on clinical interpretability. The exceptions to interpretability in the face of hardware were ventriculoperitoneal shunts, particularly those with programmable valves and siphon gauges, and large numbers of KLS-Martin maxDrive screws.
- Seizure Frequency Can Alter Brain Connectivity: Evidence from Resting-State fMRI
Resting-state fMRI data from 36 patients with hot-water epilepsy (18 with infrequent seizures) and 18 healthy age- and sex-matched controls were analyzed for seed-to-voxel connectivity. Patients in the frequent-seizure group had increased connectivity within the medial temporal structures and widespread areas of poor connectivity, including the default mode network. Seizure frequency can alter functional brain connectivity, which can be visualized by resting-state fMRI.
- Challenges in Identifying the Foot Motor Region in Patients with Brain Tumor on Routine MRI: Advantages of fMRI
Thirty-five attending-level raters evaluated 14 brain tumors involving the frontoparietal convexity. Raters identified the location of the foot motor homunculus and determined whether the tumor involved the foot motor area and/or motor cortex by using anatomic MR imaging. Seventy-seven percent of the time raters correctly identified whether the tumor was in the foot motor cortex. Raters with fMRI experience were significantly better than raters without experience at foot motor fMRI centroid predictions.