BACKGROUND: Diffusion tensor imaging (DTI) is now widely used in neurosurgery to preoperatively delineate the course of the pyramidal tract. OBJECTIVE: To evaluate the accuracy of the method by comparison with subcortical electrical stimulation and to evaluate the influence of the distance of the pyramidal tract from the tumor on the resection extent and postoperative clinical deficits. METHODS: A diffusion tensor imaging depiction of the pyramidal tract was used in preoperative planning and intraoperative navigation in 72 cases. In 36 cases, subcortical electrical stimulation was used during the resection. The preoperative tumor-to-tract distance was compared with the stimulation result, the extent of resection, and the short-term postoperative course. RESULTS: A significant nonlinear relationship between the tract-to-tumor distance and the probability of a motor response to subcortical stimulation was observed. The largest preoperatively measured tumor-to-tract distance with a positive stimulation result was 8 mm. Moreover, we observed a trend toward transient postoperative motor deterioration in patients with tumors close to the pyramidal tract. Resection extent was not significantly affected by the tumor-to-tract distance. CONCLUSION: Despite methodological obstacles, reasonable accuracy of the diffusion tensor imaging reconstructions of the pyramidal tracts was confirmed by our study. The occurrence of transient postoperative motor deterioration is higher in patients with tumors located close to the pyramidal tract.

• MeSH
• difuzní magnetická rezonance metody   MeSH
• elektrodiagnostika metody   MeSH
• hluboká mozková stimulace metody   MeSH
• lidé středního věku MeSH
• lidé MeSH
• nádory mozku patologie   chirurgie   MeSH
• předoperační péče metody   MeSH
• pyramidové dráhy patologie   MeSH
• reprodukovatelnost výsledků MeSH
• senzitivita a specificita MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky kontrolované MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH

BACKGROUND: The anatomy and somatotopy of the pyramidal tract during its course in the internal capsule has recently been discussed by many publications. However, the reports on the anatomy of the clinically more important supraventricular portion of the tract are scarce. The objective of this study is to investigate the anatomy and somatotopy of the supraventricular portion of the pyramidal tract. METHODS: In 13 patients undergoing surgery with subcortical electric stimulation for tumors located in the supraventricular white matter close to the pyramidal tract (as depicted by diffusion tensor tracking [DTT]), the relationship between the position of the stimulation point and the motor response in the arm or leg was analyzed. Additionally, the somatotopic organization of the tract was studied using separate tracking of arm and leg fibers in 20 healthy hemispheres. Finally, the course of the tract was studied by dissecting 15 previously frozen human hemispheres. RESULTS: In most cases, subcortical stimulation during the resection of tumors located behind and in front of the pyramidal tract elicited leg and arm movement, respectively. This association of stimulation point position with motor response type was significant. A DTT study of the somatotopy demonstrated a varying degree of rotation of the leg and arm fibers from mediolateral to posteroanterior configuration. Anatomic dissections demonstrated a folding-fan like structure of the pyramidal tract with a similar rotation pattern. CONCLUSION: The pyramidal tract undergoes a large part of its rotation from mediolateral to posteroanterior configuration during its course in the supraventricular white matter, although interindividual differences exist.

• MeSH
• capsula interna anatomie a histologie   fyziologie   chirurgie   MeSH
• lidé MeSH
• mapování mozku metody   MeSH
• nádory mozku chirurgie   MeSH
• neuroanatomie metody   MeSH
• pyramidové dráhy anatomie a histologie   fyziologie   chirurgie   MeSH
• retrospektivní studie MeSH
• zobrazování difuzních tenzorů metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Functional magnetic resonance imaging (fMRI) is a widely used method for research and visualization of the brain function. However, its clinical use is still limited. Our objective was to study fMRI reliability in localizing the primary hand motor cortex (M1) under pathological conditions caused by the proximity of a brain tumour. The results were then compared with standard technique of cortical function mapping-electric cortical stimulation (ECS). METHOD: We compared M1 areas localized with the fMRI and ECS in 18 patients with brain tumours in fronto-parietal regions. The 1.5 T blood oxygenation-level dependent (BOLD) fMRI was performed preoperatively using a motor task involving rhythmic touching of the thumb consecutively with other fingers on the same hand contralateral to the affected hemisphere. Each individual fMRI result was displayed at the P < 0.05 significance level corrected for family wise error (more conservative approach) or at the P < 0.001 level uncorrected (less conservative approach) and projected on the T1-weighted image used for neuronavigation. FINDINGS: In 12 patients (66.6%) we found full agreement between the fMRI and ECS. In 3 patients (16.6%) the overlap was only partial, with one ECS testing position on motor response found outside the BOLD signal cluster. In another 3 cases (16.6%) there was a discrepancy between the two methods. The fMRI sensitivity for localizing the ECS reactive M1 cortex was 71%. The fMRI/ECS consistency was within a 5-mm range in 77% of the testing positions used for ECS which complies with the inherent accuracy of the navigation system. CONCLUSIONS: Because the overlap between the two methods never exceeded 10-mm, we found that the fMRI method correctly guided the ECS to the M1 cortex in 83% of patients. Infiltrative growth of the tumour and collateral oedema were the reasons for the BOLD signal suppression in three patients. Our results support using ECS as a more reliable tool for M1 cortical mapping than fMRI.

• MeSH
• dospělí MeSH
• edém mozku patofyziologie   patologie   MeSH
• elektrická stimulace metody   MeSH
• elektrodiagnostika metody   MeSH
• elektrofyziologie metody   MeSH
• invazivní růst nádoru patofyziologie   patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mapování mozku metody   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• motorické korové centrum patofyziologie   patologie   MeSH
• mozkový krevní oběh fyziologie   MeSH
• nádory mozku chirurgie   patofyziologie   patologie   MeSH
• neuronavigace metody   MeSH
• prediktivní hodnota testů MeSH
• předoperační péče MeSH
• senzitivita a specificita MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• validační studie MeSH