A 3 tesla magnetic resonance imaging volumetric analysis of the hippocampal formation: dependence on handedness and age.

BACKGROUND: The hippocampal formation (HF) is one of the most important parts of the brain in the magnetic resonance imaging (MRI) volumetric analysis in various domains, but not completely from all aspects, including the handedness. The aim of our study was to evaluate the possible differences in the volume of the right and left HF among the healthy right-handed and left-handed subjects, and to determine whether the volume differences are age related. MATERIALS AND METHODS: The MRI of this prospective study was performed using T1 fast field echo (FFE) sequence. The 124 subsequent coronal slices (thickness 1.5 mm) were performed in each participant. The obtained HF volumes were normalised and statistically compared. Volunteers comprised 30 persons aged 22.0 years, 12 of whom were the left-handed, and 30 persons aged 75.2 years on average, 9 of whom were the left-handed. RESULTS: The right and left HF volumes averaged 2.986 cm3 and 2.858 cm3 in the right-handed, and 2.879 cm³ and 3.020 cm³ in the left-handed young volunteers, as well as 2.728 cm³ and 2.650 cm³ in the right-handed, and 2.617 cm³ and 2.780 cm³ in the left-handed elderly persons. The HF volume ratios in the young left-handed participants showed a significant left-greater-than-right asymmetry. A significant difference was also noticed within the right-to-left volume ratios of the right- and left-handed young and elderly participants. The latter reduction in the HF volume within the aged group can be interpreted as a slight atrophy of the HF. CONCLUSIONS: There is a significant difference in the volumes of the left and right HF of the left-handed young participants. The age related HF volume differences were proven between the groups of the young and elderly volunteers. The obtained data should be included into the future MRI studies of the HF volumes in various clinical domains.

Diffusion tensor MRI tractography and cognitive impairment in multiple sclerosis.

OBJECTIVE: To assess the correlation between cognitive impairment and overall vs regional CNS damage, quantified using conventional and diffusion tensor (DT) MRI tractography in multiple sclerosis (MS). METHODS: Brain dual-echo, T1-weighted, and DT MRI data were acquired from 82 patients with MS. DT tractography was used to produce maps of white matter (WM) tracts involved in cognition. The sensory thalamocortical projections and optic radiations were studied as "control" WM tracts. The contribution of global brain damage (T2 lesion volume, normalized brain volume, gray matter [GM] volume, WM volume, DT MRI measures of normal-appearing WM and GM damage) and damage to selected WM tracts to overall cognitive impairment and to impairment at individual neuropsychological tests was assessed using a random forest (RF) analysis. RESULTS: Thirty-three patients had cognitive impairment. The majority of MRI measures differed significantly between cognitively impaired and cognitively preserved (CP) patients. Significant correlations were found between performance in the majority of neuropsychological tests and global or regional brain damage (r ranging from -0.60 to 0.57). The RF analysis showed a high performance in classifying cognitively impaired vs CP patients, with a classification (C)-index = 76.8, as well as in classifying patients' impairment in individual neuropsychological tests (C-index between 75.6% and 86.6%). Measures of lesional damage in cognitive-related tracts, rather than measures of normal-appearing WM damage in the same tracts or global brain/WM/GM damage, resulted in the highest classification accuracy. CONCLUSIONS: Lesions in strategic brain WM tracts contribute to cognitive impairment in MS through a multisystem disconnection syndrome.

Papillary glioneuronal tumor: unexplored entity.

Papillary glioneuronal tumors represent a new and rare entity of an uncommon morphologic subtype of low-grade mixed neuronal-glial neoplasms with an unclear etiology. They are described as benign lesions with extraventricular localization. We report the second case of papillary glioneuronal tumor with recurrent nature after gross-total resection, and the third case of this tumor with intraventricular localization. While conventional magnetic resonance imaging of papillary glioneuronal tumors is well described in literature, there are no data based on advanced magnetic resonance techniques. The present article represents a review of clinicopathological and both conventional and advanced magnetic resonance imaging characteristics of papillary glioneuronal tumors, with focus on 2 cases with atypical course and localization.

Overcoming the clinical-MR imaging paradox of multiple sclerosis: MR imaging data assessed with a random forest approach.

BACKGROUND AND PURPOSE: In MS, the relation between clinical and MR imaging measures is still suboptimal. We assessed the correlation of disability and specific impairment of the clinical functional system with overall and regional CNS damage in a large cohort of patients with MS with different clinical phenotypes by using a random forest approach. MATERIALS AND METHODS: Brain conventional MR imaging and DTI were performed in 172 patients with MS and 46 controls. Cervical cord MR imaging was performed in a subgroup of subjects. To evaluate whether MR imaging measures were able to correctly classify impairment in specific clinical domains, we performed a random forest analysis. RESULTS: Between-group differences were found for most of the MR imaging variables, which correlated significantly with clinical measures (r ranging from -0.57 to 0.55). The random forest analysis showed a high performance in identifying impaired versus unimpaired patients, with a global error between 7% (pyramidal functional system) and 31% (Ambulation Index) in the different outcomes considered. When considering the performance in the unimpaired and impaired groups, the random forest analysis showed a high performance in identifying patients with impaired sensory, cerebellar, and brain stem functions (error below 10%), while it performed poorly in defining impairment of visual and mental systems (error of 91% and 70%, respectively). In analyses with a good level of classification, for most functional systems, damage of the WM fiber bundles subserving their function, measured by using DTI tractography, had the highest classification power. CONCLUSIONS: Random forest analysis, especially if applied to DTI tractography data, is a valuable approach, which might contribute to overcoming the MS clinical-MR imaging paradox.

A multicenter assessment of cervical cord atrophy among MS clinical phenotypes.

OBJECTIVE: In this multicenter study, a new semiautomatic method for segmenting the cervical cord from C2 to C5 was used to investigate the correlation between cord atrophy and clinical disability in a large sample of patients with multiple sclerosis (MS). METHODS: T2 and 3-dimensional T1-weighted cervical cord scans and dual-echo brain scans were acquired from 143 healthy controls, 22 patients with clinically isolated syndromes (CIS), 101 patients with relapsing-remitting MS (RRMS), 79 patients with secondary progressive MS (SPMS), 58 patients with benign MS (BMS), and 75 patients with primary progressive MS (PPMS) in 3 European centers. Normalized cervical cord cross-sectional area (CSAn) was measured by an active surface cord model. Between-group comparisons were performed using linear mixed-effect models. A nonparametric kernel estimator was used to obtain smoothed plots of CSA along the cervical cord. RESULTS: Cord CSAn was significantly lower in PPMS vs healthy controls, BMS vs RRMS, SPMS vs BMS, and RRMS. From C2 to C5, a net separation and definition of the plots of patients with BMS, PPMS, and SPMS was seen with respect to those of the other study groups. CSAn was correlated with Expanded Disability Status Scale (r = -0.49, p < 0.0001), with a differential effect among disease clinical phenotypes: no association in either CIS or in BMS; association in RRMS (r = -0.30, p = 0.001), SPMS (r = -0.34, p = 0.001), and PPMS (r = -0.27, p = 0.01). CONCLUSIONS: Cervical cord atrophy provides a relevant and useful marker for the characterization of clinical heterogeneity of patients with MS. The stability of this measure among different centers supports its use as potential outcome measure to monitor disease progression in multicenter trials.

Intraventricular textiloma with granuloma formation following third ventricle colloid cyst resection - a case report.

Despite precautions, cotton and gauze pads used for dissection or to achieve haemostasis during neurosurgical procedures can inadvertently be left behind and result in clinically symptomatic or asymptomatic and radiologically apparent mass lesion, sometimes referred to as "textilomas" or "gossypibomas", often mimicking recurrent tumour or abscess on neuroimaging studies. We report the neuroimaging evaluation, including computed tomography (CT), magnetic resonance imaging (MRI) and spectroscopy (H1-MRS), in a case of textiloma developing after the treatment of a third ventricle colloid cyst.

[Diffusion and perfusion magnetic resonance imaging in evaluation of primary glial brain tumors].

INTRODUCTION: Diffusion (DWI) and perfusion (PWI) imaging can give important data about physiological characteristics of tissue, which complete morphologic findings from conventional MRI. The aim of this study is to estimate the value of these MRI technics in evaluation of primary glial brain tumors. MATERIALS AND METHODS: The significance of DWI and PWI in differentiation of histologically proven low- and high-grade gliomas was estimated in 48 patient with diagnosed brain gliomas. ADC and rCBV values were compared by aplication of Mann-Whitney test, and logistic regression analysis was used to determine which of these two parameters contributed the most in increasing the diagnostic accuracy, ia. its sensitivity, specificity and predictive velues. ROC curves were constructed to determine threshold values for differentiation of low- from high-grade lesions. RESULTS: Statistical significance were showed between mean values of rCBV for low-grade (0.82) and high-grade (5.32) gliomas, which was not found for values of ADC parameters. Threshold rCBV value of 1.23 was determinated for discrimination between low- and high-grade gliomas with a sensitivity of 83.2% and a specificity of 77.5%. CONCLUSION: Conventional MRI combined with PWI increases the accuracy in determination of glioma grade.

[Comparative evaluation of conventinal and dynamic magnetic resonance imaging, of the pituitary microadenomas].

OBJECTIVE: This study tried to determine if there is a difference between standard and dynamic MR examination in detection of pituitary microadenoma. SUBJECTS AND METHODS: We have included twenty seven patients with suspicious pituitary tumor. All patients have been hospitalized for endocrinology examination between June 2007 and May 2008 in Institute for Endocrinology, diabetes and metabolic diseases of Clinical Center of Serbia. MR examinations have been preformed in MR Center of Clinical Center of Serbia. RESULTS: Twenty seven patients were included in our study. Only in four of them pituitary microadenoma was detected using dynamic MR examination. One was somatotrophin secreting adenoma, and three were corticotrophin realizing adenomas. There were no statistically significant differences between conventional and dynamic MR examination. CONCLUSION: Dynamic MR Examination as method can hardly match standard MR examination which remains standard in detection of pituitary microadenomas.

[Radiologic manifestation of primary pleural tumors].

OBJECTIVES: To show the radiological manifestations of primary pleural tumors. PATIENTS AND METHODS: we carried out a retrospective analysis of radiological findings in 62 patients with primary malignant tumor of pleura. RESULTS: Study included 39 male and 23 female patients. Malignant tumors were present in 92.7% of the patients and benign ones in 7.2%. The most common malignant tumor was mesothelioma (85.4%), and solitary fibrous tumor prevailed among benign tumors (9.7%). Diffuse malignant mesothelioma manifested on computed tomography (CT) as a pleural thickening and effusion in 67.4% of the patients, tumors and effusion in 11.7%, and only as an effusion in 9.8% cases. Thickening of the pleura appeared diffuse in 54% of patients and most often it had nodular pattern. Both localized malignant and all benign tumors presented as tumor-like changes with the signs of necrosis in 50%. CONCLUSION: The imaging methods have a key role in the diagnosis of pleural tumors. CT shows different morphologic features of pleural lesions that have been established as a useful tool for differentiating malignant from benign disease. However, magnetic resonance is preferred imaging method for assessing the extent and resectability of pleural tumors.

[Thoracic manifestations of gastrointestinal diseases].

Variety of gastrointestinal tract (GIT) changes that have their manifestation in thorax, disable their detailed review. Therefore, this article, represents short and overall over-view of these conditions. Standard chest x-ray can reveal esophageal disorders, herniation of abdominal organs into thorax, signs of GIT organs perforation, subphrenic abscess. Numerous diseases of intrabadominal organs of digestive tract can spread to the thorax, either per continuitatem or by lymphogenous or hemaotgenous dissemination. Therefore, chest x-ray is obliged by investigation of abdominal organs. If it is necessary additional diagnostic procedures are performed to confirm or exclude the association of lung or pleura features with GIT disorders. Above mentioned, just confirm that chest x-ray is first in algorithm of diagnostic procedures in these pathologic conditions. If there is any suspicion to conditions that require patients treatment, additional imaging methods like computerized tomography (CT), ultrasonography (US) and barium enema of digestive tract are necessary.

[Diagnostic quality of CT imaging of the thorax].

The paper is aimed at determining diagnostic quality of the images in different chest CT examination protocols. Two groups of patients underwent scanning based on two different protocols using Siemens Somatom 4 Plus scanner in the spiral mode. The study included the total of 64 patients divided in two groups according to their body weight (BW). Group one included 34 patients weighing above 80 kg and they were scanned according to the standard protocol. Group two comprised 30 patients weighting below 80 kg and they were scanned using the same protocol however with reduction of tube current of 13 mA. All the scans were subsequently reconstructed using noise-reduction filter (enhancement of low contrast resolution).

[Comparison of detection of brain lesions in multiple sclerosis in magnetic resonance imaging at magnetic field strength of 1.0 and 3.0 Tesla].

To estimate the relative sensitivity of MR examination for brain lesions in multiple sclerosis at 1.0 Tesla (T) and 3.0 T using identical acquisition conditions. 54 patients with multiple sclerosis were examined both at 1.0T (Siemens Impact Expert) and 3.0T (Philips Intera) using T1-weighted spin echo (T1W-SE) with and without gadolinium contrast injections, T2W SE and fluid attenuated inversion recovery (FLAIR) imaging. Images were examined independently by three experienced neuroradiologists using focal lesion counting. 3.0T scans compared with 1.0T scans demonstrate a 27.3%, increase in the number of detected contrast enhanced lesions and an 22.7% increase in the number of detected lesions on FLAIR MR tomograms. Highfield 3.0T MR imaging demonstrates better sensitivity in the detection of focal brain lesions in multiple sclerosis. This improvement is more apparent in contrast enhanced lesion detection and less noticeable in FLAIR detected lesions.

Late relapse of pediatric medulloblastoma.

Medulloblastoma (MB), the most common malignant brain tumor of childhood, is classified according to pathomorphologic characteristics in the group of central nervous system embryonal tumors, but both its pathogenesis and biologic behavior remain unknown. In addition, the relationship of MB to other embryonal brain tumors is debated and response to therapy is difficult to predict. The authors report an uncommon case of unfavorable late relapse, local as well as distant, in a 26-year old male patient, who was free of disease and without treatment-related morbidity for fifteen years after combined therapy for pediatric MB.