Agata Majos

Cortical mapping by functional magnetic resonance imaging in patients with brain tumors

The aim of our study was to establish the effectiveness of the functional MRI (fMRI) technique in comparison with intraoperative cortical stimulation (ICS) in planning cortex-saving neurosurgical interventions. The combination of sensory and motor stimulation during fMRI experiments was used to improve the exactness of central sulcus localization. The study subjects were 30 volunteers and 33 patients with brain tumors in the rolandic area. Detailed topographical relations of activated areas in fMRI and intraoperative techniques were compared. The agreement in the location defined by the two methods for motor centers was found to be 84%; for sensory centers it was 83%. When both kinds of activation are taken into account this agreement increases to 98%. A significant relation was found between fMRI and ICS for the agreement of the distance both for motor and sensory centers (p=0.0021–0.0024). Also a strong dependence was found between the agreement of the location and the agreement of the distance for both kinds of stimulation. The spatial correlation between fMRI and ICS methods for the sensorimotor cortex is very high. fMRI combining functional and structural information is very helpful for preoperative neurosurgical planning. The sensitivity of the fMRI technique in brain mapping increases when using both motor and sensory paradigms in the same patient.

The Aberrant Right Subclavian Artery (Arteria Lusoria): The Morphological and Clinical Aspects of One of the Most Important Variations—A Systematic Study of 141 Reports

The most important abnormality of the aortic arch is arguably the presence of an aberrant right subclavian artery (arteria lusoria). If this vessel compresses the adjacent structures, several symptoms may be produced. The aim of the study is to present the morphological and clinical aspects of the aberrant right subclavian artery. Three different databases searched for a review of pertinent literature using strictly predetermined criteria. Of 141 cases, 15 were cadaveric and 126 were clinically documented. The gender distribution of the subjects was 55.3% female and 44.7% male. The mean age of the patients at symptoms onset was 49.9 ± 19.4 years for all patients but 54.0 ± 19.6 years and 44.9 ± 18.1 years for female and male subjects, respectively (P = 0.0061). The most common symptoms in this group were dysphagia (71.2%), dyspnea (18.7%), retrosternal pain (17.0%), cough (7.6%), and weight loss (5.9%). The vascular anomalies coexisting with an arteria lusoria were truncus bicaroticus (19.2%), Kommerells diverticulum (14.9%), aneurysm of the artery itself (12.8%), and a right sided aortic arch (9.2%). In conclusion, compression of adjacent structures by an aberrant right subclavian artery needs to be differentiated from other conditions presenting dysphagia, dyspnea, retrosternal pain, cough, and weight loss.

Hand exercise test for the assessment of endothelium-dependent vasodilatation in subjects with type 1 diabetes.

BACKGROUND At present, endothelial dysfunction is best assessed in vivo with measurement of flow-mediated dilatation (FMD) with Doppler ultrasound scanning. This test, however, does not account for the subjects age and is uncomfortable for patients. The aim of the study was to compare a new test for endothelium function assessment using hand exercise load. METHODS The study group comprised 31 male patients with type 1 diabetes and 72 healthy men as controls. The subjects in both groups were subdivided into three age groups: 18-30 (subgroup A), 31-45 (subgroup B), and 46-60 (subgroup C) years. FMD of the brachial artery with induction of hand ischemia was conducted in all the subjects. Afterwards, an originally designed test using standardized hand exercise with the use of a training device was performed. RESULTS In the youngest group of type 1 diabetes patients the effect of hand ischemia on brachial artery diameter was greater than in the two older age subgroups: baseline artery diameter increased by 0.23 +/- 0.11 mm (5.7%), 0.19 +/- 0.09 mm (4.3%), and 0.13 +/- 0.02 mm (2.8%), respectively (P < 0.01). In the hand exercise test, artery diameter increased in the youngest subjects by 0.39 +/- 0.11 mm (9.5%) and in the two older groups by 0.26 +/- 0.07 mm (5.6%) and 0.18 +/- 0.09 mm (4.5%) (P < 0.05), respectively. In subgroups A, B and C, vasodilation after hand exercise test was greater by 67%, 30%, and 32% (P < 0.01), respectively, compared with the effect of the ischemic test. In the controls similar effects and relationship between ischemic and hand exercise tests were noted, however, with a smaller difference between the two tests. CONCLUSIONS The hand exercise test results in a greater difference in vessel diameter before and after the test stimulus, which might substantially improve its feasibility. The hand exercise test could be a useful alternative tool for endothelial function assessment, especially in type 1 diabetes subjects.

Fenestration and duplication of the vertebral artery: the anatomical and clinical points of view.

The vertebral artery (VA) acts as a foundation for the posterior circulation of the head and neck. It presents a number of anomalies that can be easily visualized thanks to modern imaging techniques, such as MR and CT angiography or color Doppler ulrasonography. Determining the appropriate terminology for those anomalies can be sometimes more challenging than their recognition. One particular challenge concerns the differentiation betweenVA fenestration and duplication. Because of the different clinical prognoses associated with those anomalies, confusion should be avoided. Knowledge of the morphological anomalies associated with the VA is important for both radiologists and head and neck surgeons, because any injury to the VA can result in a threat to the vascular supply of the brain stem, the cerebral or cerebellar hemispheres, the thalamus, cervical nerve roots and particularly the lateral medulla (Wallenbergs syndrome). This article analyses world literature concerning the issue of VA fenestration and duplication to facilitate a differential diagnosis. Clin. Anat. 26:933–943, 2013.

A proposal for classification of the superior transverse scapular ligament: variable morphology and its potential influence on suprascapular nerve entrapment

BACKGROUND The suprascapular region is the most common site of suprascapular nerve entrapment. The aim of the present study was to determine the morphologic variation of the superior transverse scapular ligament (STSL) and measure the reduction in size of the suprascapular opening. Other structures that might be potentially significant during open and arthroscopic procedures in this region are also described. MATERIALS AND METHODS The study used 86 randomized formalin-fixed human cadaveric shoulders. After dissection of the suprascapular region, the following measurements were defined and collected for every STSL: length, proximal width, distal width, and thickness at the proximal and distal ends. Measurements were also taken of the area of the suprascapular opening (aSSO) and the middle width of the suprascapular opening (mwSSO). RESULTS Three types of STSL may be distinguished: a fan-shaped type (54.6%), a band-shaped type (41.9%), and a bifid type (3.5%). Statistically significant differences between the specimens with fan-shaped and band-shaped types of STSL were observed in aSSO and mwSSO of the suprascapular opening. Anterior coracoscapular ligaments (ACSL) were present in 44 of 86 shoulders. The aSSO and mwSSO were smaller in specimens with an ACSL than in those without; however, this difference was only significant in the band-shaped type of STSL. CONCLUSION Knowledge of the morphologic variations of STSL presented in this study is important for better understanding the possible anatomic conditions that can promote suprascapular nerve entrapment and should be taken into particular consideration during surgical and arthroscopic procedures around the suprascapular notch.

Morphological and Radiological Study of Ossified Superior Transverse Scapular Ligament as Potential Risk Factor of Suprascapular Nerve Entrapment

The suprascapular notch is covered superiorly by the superior transverse scapular ligament. This region is the most common place of suprascapular nerve entrapment formation. The study was performed on 812 specimens: 86 dry scapulae, 104 formalin-fixed cadaveric shoulders, and 622 computer topography scans of scapulae. In the cases with completely ossified superior transverse scapular ligament, the following measurements were performed: proximal and distal width of the bony bridge, middle transverse and vertical diameter of the suprascapular foramen, and area of the suprascapular foramen. An ossified superior transverse scapular ligament was observed more often in men and in the right scapula. The mean age of the subjects with a completely ossified superior transverse scapular ligament was found to be similar than in those without ossification. The ossified band-shaped type of superior transverse scapular ligament was more common than the fan-shaped type and reduced the space below the ligament to a significantly greater degree. The ossified band-shaped type should be taken into consideration as a potential risk factor in the formation of suprascapular nerve entrapment. It could explain the comparable frequency of neuropathy in various populations throughout the world despite the significant differences between them in occurrence of ossified superior transverse scapular ligament.

Rearrangement of motor centers and its relationship to the neurological status of low-grade glioma examined on pre- and postoperative fMRI

OBJECTIVE Well-developed compensatory mechanisms, based on the phenomenon of brain plasticity, exist in patients with neuroepithelial tumors, especially with highly differentiated gliomas (WHO grade II). We studied phenomenon of rearrangement of sensorimotor cortex using functional magnetic resonance imaging (fMRI), and verified relationship between observed changes and results of neurological and neuropsychological assessment. METHODS Study group included 20 patients with WHO grade II gliomas located within motor or sensory cortex. fMRI examination, as well as clinical, neurological (Karnofsky performance score [KPS] and Lovetts scale [Lo]), and neuropsychological assessment (Digit Coding Symbol Test and Digit Span Test) were performed pre-operatively and 3 months post-surgery. RESULTS There were no significant differences in pre- and postoperative performance status of patients. Although statistically insignificant, an increase in frequency of activation of primary and secondary cortical motor centers was observed postoperatively (p>0.05). Prior to surgery, motor centers were characterized by lower values of t-statistics than in postoperative period (p>0.05). In contrast, values of parameters describing the size of examined centers, i.e. mean number of clusters, were lower, but not statistically significant on postoperative examination (p>0.05). Compared to individuals without motor deficit, patients with preoperative Lo3/Lo4 paralysis showed significantly higher mean values of t-statistics in the accessory motor area on postoperative examination (p<0.05). CONCLUSIONS The processes of motor cortex rearrangement seemed to be associated with the pre- and postoperative neurological and neuropsychological status of patients. After contralateral primary motor cortex, accessory motor area was the second most frequently activated center, both pre- and postoperatively.

Duplication of the left vertebral artery in a patient with dissection of the right internal carotid artery and Ehlers–Danlos syndrome: case report and review of the literature

Duplication of the left vertebral artery was observed in a 43-year-old Caucasian male with dissection of the right internal carotid artery during multidetector 64-row computer tomography and Doppler ultrasonography B-flow mode. Both duplicated segments arose from the left subclavian artery and united at levels C5–C6 to form a single vessel. The presented case describes precisely the origin and diameter of both vertebral arteries. Additionally, after all procedures associated with diagnosis and treatment of the patient, Ehlers–Danlos syndrome type IV was diagnosed. The lumen of the duplicated vertebral artery was smaller than normal; it can be concluded that this variant has clinical implications and should be taken into consideration when vertebral arteries need catheterization.

Functional rearrangement of language areas in patients with tumors of the central nervous system using functional magnetic resonance imaging.

Summary Background: The aim of this study was to determine the reorganization of the language areas in patients with tumors located near speech centers using functional magnetic resonance imaging (fMRI). Material/Methods: fMRI was performed prior to the surgical treatment of 11 right-handed patients with tumors located close to the Broca’s or Wernicke’s areas of the left hemisphere. The analysis included a record of the activity in four regions of interest (ROIs): Broca’s and Wernicke’s areas, and their anatomic homologues in the right hemisphere. For each patient a regional lateralization index was calculated separately for Broca’s area versus its right-hemisphere homolog and Wernicke’s area versus its right-hemisphere homolog. The results were correlated with the histopathological type of the tumor and its size. Results: Our fMRI examinations showed activation of the Broca’s area in the right hemisphere in 3/4 cases of low grade gliomas (LGG) localized in the left frontal lobe. In one case of the high grade glioma (HGG) only the left hemisphere Broca’s area was activated (LI=1). Activation in Wernicke’s area in both hemispheres was obtained irrespective of the size and histological type of the tumor. All tumors localized in the left temporal lobe were HGG. We obtained activation only in the right hemisphere Wernicke’s area in 4/5 of the cases. In 4/5 of the cases activation in Broca’s area was present- in 2 cases in the left hemisphere, in 1 case in the right hemisphere and in 1 case bilateral. Conclusions: The presence of a neoplastic lesion in close topographic relationship to language areas induces their functional reorganization. fMRI is an useful method for determination of language areas localization in pre-operative planning. HGG tumors localized near Wernicke’s area lead to transfer its function to the healthy hemisphere and/or to decreased activity in the affected hemisphere.

Process of the Functional Reorganization of the Cortical Centers for Movement in GBM Patients: fMRI Study

PurposeThe aim of this study was to verify whether the functional reorganization of motor cortex is associated with the increase in the size of WHO type IV glioma lesion, that is, disease duration and development, and whether surgical treatment has an impact on cerebral plasticity.MethodsThe study included 16 patients with primary tumors of the brain located at the region of central sulcus. The clinical status of patients and tumor volume was determined. Functional magnetic resonance imaging examinations were performed before and 3 months after operation.ResultsThe activity of all cortical centers, both contralateral and ipsilateral, was observed in a group of small as well as large tumors. The intensity of activation and the number of activated clusters of small tumors were almost always higher as compared with the large tumors. The frequency of the activity of contralateral areas was similar during the first and the second examination. In the case of ipsilateral centers, the frequency of activation during the second examination was lower. Mean values of t-statistics during the first examination were higher than during the second examination. Supplementary motor area (SMAa) was the only center for which the mean values of activation intensity remained similar.ConclusionsSMAa seems to play the most important role in the processes of motor cortex plasticity in high-grade glioma patients. Surgery seems not having a significant influence on the pattern of functional reorganization of the cortical centers for movement. Identification of the individual patterns of the reorganization of motor centers plays an important role in clinical practice.