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Purpose: Functional MRI is not routinely used for neurosurgical planning despite potential important advantages, due to difficulty of determining quality. We introduce a novel method for objective evaluation of fMRI scan quality, based on activation maps. A template matching analysis (TMA) is presented and tested on data from two clinical fMRI protocols, performed by healthy controls in seven clinical centers. Preliminary clinical utility is tested with data from low-grade glioma patients., Methods: Data were collected from 42 healthy subjects from seven centers, with standardized finger tapping (FT) and verb generation (VG) tasks. Copies of these "typical" data were deliberately analyzed incorrectly to assess feasibility of identifying them as "atypical." Analyses of the VG task administered to 32 tumor patients assessed sensitivity of the TMA method to anatomical abnormalities., Results: TMA identified all atypical activity maps for both tasks, at the cost of incorrectly classifying 3.6 (VG)-6.5% (FT) of typical maps as atypical. For patients, the average TMA was significantly higher than atypical healthy scans, despite localized anatomical abnormalities caused by a tumor., Conclusion: This study supports feasibility of TMA for objective identification of atypical activation patterns for motor and verb generation fMRI protocols. TMA can facilitate the use and evaluation of clinical fMRI in hospital settings that have limited access to fMRI experts. In a clinical setting, this method could be applied to automatically flag fMRI scans showing atypical activation patterns for further investigation to determine whether atypicality is caused by poor scan data quality or abnormal functional topography.

Bradykinesia-the cardinal symptom in Parkinson's disease (PD)-affects both upper and lower limbs. While several functional imaging studies investigated the impact of levodopa on movement-related neural activity in Parkinson's disease during upper limb movements, analogue studies on lower limb movements are rare. We studied 20 patients with PD (mean age 66.8 ± 7.2 years) after at least 12 h drug withdrawal (OFF-state) and a second time approximately 40 min after oral administration of 200 mg levodopa (ON-state) behaviourally and by functional magnetic resonance imaging (fMRI) at 3 T during externally cued active ankle movements of the more affected foot at fixed rate. Results were compared with that obtained in ten healthy controls (HC) to separate pure pharmacological from disease-related levodopa-induced effects and to allow for interaction analyses. Behaviourally, all patients improved by at least 20 % regarding the motor score of the Unified Parkinson's disease rating scale after levodopa-challenge (mean scores OFF-state: 38.4 ± 10.1; ON-state: 25.5 ± 8.1). On fMRI, levodopa application elicited increased activity in subcortical structures (contralateral putamen and thalamus) in the patients. In contrast, no significant levodopa-induced activation changes were found in HC. The interaction between "PD/HC group factor" and "levodopa OFF/ON" did not show significant results. Given the levodopa-induced activation increases in the putamen and thalamus with unilateral ankle movements in patients with PD but not in HC, we speculate that these regions show the most prominent response to levodopa within the cortico-subcortical motor-circuit in the context of nigrostriatal dysfunction.

Bradykinesia represents one of the cardinal and most incapacitating features of Parkinson's disease (PD). In this context, investigating the cerebral control mechanisms for limb movements and defining the associated functional neuroanatomy is important for understanding the impaired motor activity in PD. So far, most studies have focused on motor control of upper limb movements in PD. Ankle movement functional MRI (fMRI) paradigms have been used to non-invasively investigate supraspinal control mechanisms relevant for lower limb movements in healthy subjects, patients with Multiple sclerosis, and stroke. Using such an active and passive paradigm in 20 PD patients off medication (mean age 66.8 ± 7.2 years) and 20 healthy controls (HC; mean age 62.3 ± 6.9 years), we here wished to probe for possible activation differences between PD and HC and define functional correlates of lower limb function in PD. Active ankle movement versus rest was associated with a robust activation pattern in expected somatotopy involving key motor areas both in PD and HC. However, contrasting activation patterns in patients versus controls revealed excess activation in the patients in frontal regions comprising pre-supplementary motor areas (pre-SMA) and SMA proper. The extent of SMA activation did not correlate with behavioural parameters related to gait or motor function, and no differences were seen with the passive paradigm. This finding might be indicative of higher demand and increased effort in PD patients to ensure adequate motor function despite existing deficits. The missing correlation with behavioural variables and lack of differences with the passive paradigm suggests that this excess activation is not exclusively compensatory and also not hard-wired.