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Background: Neuroanatomical abnormalities, including cingulate cortex volume abnormalities, are a common feature in psychosis. However, the extent to which these are related to a vulnerability to psychosis, as opposed to the disorder per se, is less certain. AIM UND HYPOTHESES: The aim of the present study is to compare cingulate gray matter volumes in different stages of psychosis. We reviewed previous studies of subjects in a prodromal stage of psychosis and tested cingulate volume changes during the transition to psychosis., Methods: A cross-sectional MRI study of manually traced cingulate gray-matter volumes in 37 individuals with an at risk mental state (ARMS) for psychosis, 23 individuals with a first-episode psychosis (FEP), and 22 healthy controls (HC) was performed using a 1.5 T MRI-scanner. 16 of 37 ARMS individuals (43 %) developed psychosis during follow up (ARMS-T), whereas 21 did not (ARMS-NT). The mean duration of follow up in ARMS was 25.1 months. 8 cingulate subregions were analysed in a region-of-interest analysis., Results: Compared to HC, subjects with an ARMS had significantly reduced left caudal anterior cingulate cortex volume (p < 0.027). This finding was also evident at a trend level (p: 0.069) in FEP patients. Within ARMS, the ARMS-T group showed a significantly reduced whole right cingulate cortex (p: 0.036), right subgenual cingulate cortex (p: 0.036) and right posterior cingulate cortex (p: 0.012) compared to ARMS-NT., Discussion: These results suggest that the at risk mental state is associated with cingulate volume reductions, in particular in the left caudal anterior cingulate cortex (CACC). These abnormalities do not only seem to occur with transition to psychosis, but may be a correlate of an increased vulnerability to psychosis.

Different mechanisms have been hypothesized as contributing to abduction deficit in high myopia: the size of the eye within the orbit, tightness of the medial rectus muscles, decompensation of longstanding esotropia, and inferior displacement of the lateral rectus muscle. Using oculodynamic magnetic resonance imaging, enhanced by computer-aided visualization, we demonstrate globe restriction by the medial orbital wall on abduction in a patient with high myopia.

Background: Individuals with an At Risk Mental State (ARMS) have a very high risk of developing a psychotic disorder but the basis of this risk is unclear. We addressed this issue by studying gray matter volume in this group with magnetic resonance imaging (MRI)., Methods: Thirty-five individuals with an ARMS, 25 patients with first episode schizophrenia, and 22 healthy volunteers were studied using a 1.5T MRI scanner. Twelve (34%) of the ARMS group developed schizophrenia in the 2 years subsequent to scanning., Results: There were significant volumetric differences between the three groups in the left insula, superior temporal gyrus, cingulate gyrus and precuneus. In these regions, the volume in the ARMS group was smaller than in volunteers but not significantly different from that in the first episode (FE) group. Direct comparison of the ARMS and control groups revealed additional areas of reduced volume in the left medial temporal cortex. Within the ARMS group, those subjects who later developed psychosis had less gray matter than subjects who did not in the right insula, inferior frontal and superior temporal gyrus., Conclusions: The ARMS was associated with reductions in gray matter volume in areas that are also reduced in schizophrenia, suggesting that these are a correlate of an increased vulnerability to psychosis. Volumetric differences within the ARMS group may be related to the subsequent onset of schizophrenia in a subset of those at high risk.

The aim of our study was to determine whether T2-weighted (T2w) MRI of the brain could be performed immediately after the administration of gadopentetate dimeglumine (gadolinium DTPA) in patients with multiple sclerosis (MS) without a loss in image quality or diagnostic reliability. Sixteen patients with clinically diagnosed MS were included in the study. Twenty-four patients with various cerebral pathologies (14 patients with multiple lacunar lesions) were examined in order to exclude masking of T2 hyperintense lesions other than MS lesions. Images of 10 patients without pathological changes served as a control condition for the qualitative analysis. In these 50 patients, T1w and T2w MRI was performed before and after the administration of gadolinium DTPA. Signal intensities were measured within T2 hyperintense cerebral lesions, in T1-enhancing lesions and in normal appearing brain tissue on T2w turbo spin-echo (TSE) sequences. Both quantitative and qualitative analysis did not show significant differences between T2w pre- and postcontrast series. T2w MRI performed prior to and after the administration of gadolinium DTPA provides similar information in patients with MS. With a TR of 3.2 s, not a single lesion was obscured on T2w postcontrast series. Acquisition of T2w MR images immediately after the administration of gadolinium DTPA allows for shorter examination time and assures sufficient time for contrast enhancement in cerebral lesions with a disrupted blood-brain barrier.

Purpose: To examine whether an internal carotid artery (ICA) steno-occlusive disease leads to a reduced blood oxygenation level dependent (BOLD)-signal change due to a decreased vasodilatory reserve capacity., Materials and Methods: Patients suffering from unilateral ICA stenosis or occlusion were examined using functional magnetic resonance imaging (fMRI) of the auditory cortex with a bilateral stimulation applying a pulsed 1000 Hz sine-tone., Results: Compared to control subjects, who showed symmetric bilateral BOLD-responses within the auditory cortex, the ICA patients revealed either a normal bilateral cortical activation pattern or a reduced cortical activation on the steno-occluded side. This latter decrease of BOLD-signal change might indicate a depressed vasomotor reserve capacity. The observed coincidence between this asymmetric reduction in BOLD-signal and ischemic borderzone lesions on the affected side in this subgroup of patients strongly supports this assumption., Conclusion: This study shows that fMRI of the auditory cortex appears to have clinical merit in the workup of cerebrovascular conditions., (Copyright 2002 Wiley-Liss, Inc.)

We report a case of a prenatally diagnosed infratentorial subdural hemorrhage. The hematoma located in the posterior cerebral fossa was detected by conventional ultrasound at 24 weeks of gestation. Intrauterine magnetic resonance imaging confirmed the diagnosis. Autopsy of the fetus revealed a well-circumscribed subdural hematoma. The prenatal findings of intracranial bleeding located in the posterior fossa and the prognosis of such cases are discussed.

Cells of the mononuclear phagocytotic system (MPS) are often found near to or within ischemic tissue and can potentially aggravate cellular damage. Hence, visualization of those cells would allow demarcation of putatively affected from intact tissue. Experimental MRI studies have shown that ultrasmall particles of dextran-coated iron oxide (USPIO) are internalized into cells of the MPS. To test if this cell tagging method may be also applied to cerebral infarction, USPIOs were administered to Fisher rats 5.5 h after permanent occlusion of the middle cerebral artery (pMCAO). During the first 2 days USPIO were preferentially found in patches within the lesion and in surrounding areas. On day 4, USPIOs expanded within the core of the lesion. On day 7 they were found predominantly within the boundary area. Histological analysis showed large populations of macrophages containing iron particles in the infarcted tissue. We conclude, therefore, that it is possible to monitor MPS activity after focal cerebral ischemia using USPIOs., (Copyright 2001 Wiley-Liss, Inc.)

Functional MR imaging (fMRI) is being used increasingly to explore the human central auditory system. The considerable background noise produced by echo-planar imaging (EPI) and other fMRI sequences, however, interferes in an unpredictable way with the experimental stimuli. Several approaches exist to overcome this problem. Each has its advantages and disadvantages. These different approaches allow researchers to tailor the experimental designs to specific research questions. Recent studies have yielded significant information about human auditory function. Compared with other sensory systems such as the visual system, the auditory database still is relatively small. It is expected that novel methodologic approaches will stimulate scientific exploration of auditory processing and eventually lead to clinically meaningful applications of auditory fMRI.

The effects of ethanol on acoustically stimulated blood oxygenation level-dependent (BOLD) signal response in healthy humans was examined with echo planar functional magnetic resonance imaging (fMRI). An acquisition mode minimizing neuronal activation by scanner noise in combination with acoustic excitation by a pulsed 1000-Hz sine tone was used. Paradigms were repeated three times before and after the ingestion of 0.7 g of ethanol/kg(body weight). Linear correlation analyses (r>/=0.40) revealed bilateral BOLD responses in the auditory cortex. Significant voxels covered a cortical volume of approximately 3 ml that was reduced by approximately 40% after ethanol. The BOLD signal change initially reaching approximately 3% was reduced by 12-27%, depending on the definition of the region of interest for signal quantitation. Because ethanol produces vasodilation, the hemodynamic contribution to the BOLD signal change was estimated by modeling the relationship between regional cerebral blood flow (rCBF) and BOLD signal changes. Assuming a baseline flow increase by 10% after ethanol intake, the resulting 'Flow-BOLD-Dependence' (FBD) curve suggested that the ethanol-related BOLD signal reduction was approximately 7-12% greater than the reduction contributed purely by vasodilation. However, simultaneous determination of rCBF and regional cerebral blood volume would be required for an exact quantitation of the neuronally induced BOLD response. Although the FBD model needs empirical validation, its cautious implementation appears to be helpful if fMRI is used in combination with vasoactive drugs.

Since the pathogenesis of multiple sclerosis (MS) lesions is not yet fully understood, we investigated the potential of dynamic susceptibility contrast (DSC) magnetic resonance (MR) perfusion imaging for a better characterization of lesion pathology. Twenty-five MS patients were examined on a 1.5 T scanner. A single dose of gadolinium (Gd)-DOTA contrast agent was injected, and echoplanar images were acquired every 0.5 seconds for 1 minute. From the signal intensity-versus-time curves, the relative cerebral blood volume (rCBV) was evaluated for regions in plaques and in gray and white matter. The rCBV calculated for acute, Gd-enhancing plaques was corrected for the effects of blood-brain barrier leakage, using a new correction algorithm. Acute plaques had significantly higher blood volumes than normal-appearing white matter (P < = 0.01). Chronic plaques that appeared hypointense on T(1)-weighted images had lower rCBV than T(1)-isointense plaques (P < = 0.03). Our results indicate that the acute phase in MS is accompanied by vasodilation. In later stages of gliosis, the perfusion decreases with increasing axonal injury. Although the DSC technique is less sensitive than conventional MR imaging, the information provided is essentially different from that obtained with any other MR method.

We evaluated the effect of consensus formation and training on the agreement between observers in scoring the number of new and enlarging multiple sclerosis (MS) lesions on serial T2-weighted MRI studies. The baseline and month 9 MRI studies of 16 patients with a range of MRI activity were used (dual-echo conventional spin-echo sequence, TR 2000, TE 34 and 90 ms, 5 mm contiguous slices, inplane resolution 1 mm). First, the serial studies were visually analysed for the presence of new and enlarging lesions, on two occasions, by five experienced observers, without adopting any consensus strategy and in isolation. Next, the observers met to identify the common sources of inconsistencies in reporting between observers and formulate consensus rules. Finally, a further independent reading session was performed on the same MRI dataset, this time applying the consensus rules. Agreement between observers was assessed using kappa scores. Without the consensus rules, interobserver kappa scores for the first and second reading sessions for new lesions were only 0.51 and 0.39 respectively; agreement for enlarging lesions was even worse. The mean intraobserver kappa score for new lesions was higher at 0.72, reflecting the fact that the observers were consistently applying their individual assessment strategies. Application of the consensus rules did not lead to a significant improvement in inter observer kappas; the kappa scores adopting the guidelines were 0.46 and 0.21 for new and enlarging lesions respectively. Consensus guidelines thus did not improve the reproducibility of visual analysis of serial T2-weighted MRI, and the level of agreement between observers remained only moderate. Suboptimal repositioning is likely to be a major source of residual variability and this suggests a future role for image registration strategies; until then, a single observer, or pair of observers working in consensus, should be used in MS studies.

Magnetic resonance imaging (MRI) is highly sensitive to pathological tissue changes in multiple sclerosis (MS) patients. It demonstrates the frequently subclinical disease activity and follow-up examinations regularly show the accumulation of new lesions and the development of atrophy. The increasing importance of follow-up examinations in MS patients makes it necessary to provide comparable MRI data even over long observation periods. This review article focusses on critical variables in this regard and technical issues; practical guidelines for MRI protocols in MS patients are presented. The influence of field strength, MR systems from different manufacturers, and new software releases is described. Guidelines concerning the graphic planning of the examination, sequence protocols, documentation and reporting of cranial MR studies in MS patients are presented.

An automatic fMRI protocol for the investigation of the human auditory cortex has been developed. For the activation of the auditory system, the scanner noise itself is the source of sound. Rapid switching of B0 gradients allows the generation of tones of defined frequencies and amplitude on a conventional scanner without hardware change. No additional device for sound generation or sound delivery is needed. The proposed technique allows functional MRI of the auditory cortex in a clinical routine session.

Cavernous haemangiomas are most commonly found in the subcortical white matter, the pons and the external capsule. We present a case of a cavernous haemangioma that appeared as an intraventricular mass at the foramen of Monro. Despite the unusual location the diagnosis was established by MRI because of the typical appearance. The differential diagnosis included primary and secondary neoplasms at the foramen of Monro.

MRA (magnetic resonance angiography) is besides duplex sonography at present the only noninvasive method for vascular visualisation. The technical fundamentals and our initial experiences with this new technique of angiography in the visualisation of the basilar artery are presented in the following article.

The rationale and design of a prospective randomized double blind study of 15 +/- Deoxyspergualin in the treatment of Multiple Sclerosis are presented. The study was started in autumn 1992 and will include more than 200 patients who will be randomized either to DSG low dose or DSG high dose or placebo. Average number of contrast enhancing lesions in monthly cranial MRIs during the first six months of treatment and change in EDSS at the end of the two-year study period will be the main efficacy parameters.

The neurological symptoms of patients with multiple sclerosis are located to four brain areas and are compared with the demonstrated Magnetic Resonance Imaging (MRI) lesions. Areas mostly involved are the centrum semiovale, the periventricular space, the cerebellum and the brain stem. There is a good correlation of the different clinical locations and the MRI lesions in general. Only in the cerebrum lesions are more frequent than expected. In individual patients correlations are difficult to achieve especially in the cerebellum and the spinal cord. Repeated, complete studies of the brain and the spinal cord with contrast medium are necessary to improve the results.