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Purpose We compared fractional anisotropy and radial diffusivity measurements between pediatric canines affected with mucopolysaccharidosis I and pediatric control canines. We hypothesized that lower fractional anisotropy and higher radial diffusivity values, consistent with dysmyelination, would be present in the mucopolysaccharidosis I cohort. Methods Six canine brains, three affected with mucopolysaccharidosis I and three unaffected, were euthanized at 7 weeks and imaged using a 7T small-animal magnetic resonance imaging system. Average fractional anisotropy and radial diffusivity values were calculated for four white-matter regions based on 100 regions of interest per region per specimen. A 95% confidence interval was calculated for each mean value. Results No difference was seen in fractional anisotropy or radial diffusivity values between mucopolysaccharidosis affected and unaffected brains in any region. In particular, the 95% confidence intervals for mucopolysaccharidosis affected and unaffected canines frequently overlapped for both fractional anisotropy and radial diffusivity measurements. In addition, in some brain regions a large range of fractional anisotropy and radial diffusivity values were seen within the same cohort. Conclusion The fractional anisotropy and radial diffusivity values of white matter did not differ between pediatric mucopolysaccharidosis affected canines and pediatric control canines. Possible explanations include: (a) a lack of white matter tissue differences between mucopolysaccharidosis affected and unaffected brains at early disease stages; (b) diffusion tensor imaging does not detect any existing differences; (c) inflammatory processes such as astrogliosis produce changes that offset the decreased fractional anisotropy values and increased radial diffusivity values that are expected in dysmyelination; and (d) our sample size was insufficient to detect differences. Further studies correlating diffusion tensor imaging findings to histology are warranted.

Purpose The purpose of this study was to investigate a novel tensor shape plot analysis technique of diffusion tensor imaging data as a means to assess microstructural differences in brain tissue. We hypothesized that this technique could distinguish white matter regions with different microstructural compositions. Methods Three normal canines were euthanized at seven weeks old. Their brains were imaged using identical diffusion tensor imaging protocols on a 7T small-animal magnetic resonance imaging system. We examined two white matter regions, the internal capsule and the centrum semiovale, each subdivided into an anterior and posterior region. We placed 100 regions of interest in each of the four brain regions. Eigenvalues for each region of interest triangulated onto tensor shape plots as the weighted average of three shape metrics at the plot's vertices: CS, CL, and CP. Results The distribution of data on the plots for the internal capsule differed markedly from the centrum semiovale data, thus confirming our hypothesis. Furthermore, data for the internal capsule were distributed in a relatively tight cluster, possibly reflecting the compact and parallel nature of its fibers, while data for the centrum semiovale were more widely distributed, consistent with the less compact and often crossing pattern of its fibers. This indicates that the tensor shape plot technique can depict data in similar regions as being alike. Conclusion Tensor shape plots successfully depicted differences in tissue microstructure and reflected the microstructure of individual brain regions. This proof of principle study suggests that if our findings are reproduced in larger samples, including abnormal white matter states, the technique may be useful in assessment of white matter diseases.

Detecting circulating tumor cells (CTCs) with high sensitivity and specificity is critical to management of metastatic cancers. Although immuno-magnetic technology for in vitro detection of CTCs has shown promising potential for clinical applications, the biofouling effect, i.e., non-specific adhesion of biomolecules and non-cancerous cells in complex biological samples to the surface of a device/probe, can reduce the sensitivity and specificity of cell detection. Reported herein is the application of anti-biofouling polyethylene glycol-block-allyl glycidyl ether copolymer (PEG-b-AGE) coated iron oxide nanoparticles (IONPs) to improve the separation of targeted tumor cells from aqueous phase in an external magnetic field. PEG-b-AGE coated IONPs conjugated with transferrin (Tf) exhibited significant anti-biofouling properties against non-specific protein adsorption and off-target cell uptake, thus substantially enhancing the ability to target and separate transferrin receptor (TfR) over-expressed D556 medulloblastoma cells. Tf conjugated PEG-b-AGE coated IONPs exhibited a high capture rate of targeted tumor cells (D556 medulloblastoma cell) in cell media (58.7 ± 6.4%) when separating 100 targeted tumor cells from 1×105 non-targeted cells and 41 targeted tumor cells from 100 D556 medulloblastoma cells spiked into 1 mL blood. It is demonstrated that developed nanoparticle has higher efficiency in capturing targeted cells than widely used micron-sized particles (i.e., Dynabeads®).

Magnetic resonance imaging studies of maltreated children with posttraumatic stress disorder (PTSD) suggest that maltreatment-related PTSD is associated with adverse brain development. Maltreated youth resilient to chronic PTSD were not previously investigated and may elucidate neuromechanisms of the stress diathesis that leads to resilience to chronic PTSD. In this cross-sectional study, anatomical volumetric and corpus callosum diffusion tensor imaging measures were examined using magnetic resonance imaging in maltreated youth with chronic PTSD (N = 38), without PTSD (N = 35), and nonmaltreated participants (n = 59). Groups were sociodemographically similar. Participants underwent assessments for strict inclusion/exclusion criteria and psychopathology. Maltreated youth with PTSD were psychobiologically different from maltreated youth without PTSD and nonmaltreated controls. Maltreated youth with PTSD had smaller posterior cerebral and cerebellar gray matter volumes than did maltreated youth without PTSD and nonmaltreated participants. Cerebral and cerebellar gray matter volumes inversely correlated with PTSD symptoms. Posterior corpus callosum microstructure in pediatric maltreatment-related PTSD differed compared to maltreated youth without PTSD and controls. The group differences remained significant when controlling for psychopathology, numbers of Axis I disorders, and trauma load. Alterations of these posterior brain structures may result from a shared trauma-related mechanism or an inherent vulnerability that mediates the pathway from chronic PTSD to comorbidity.

Tumor recurrence following surgery is a common and unresolved medical problem of great importance since surgery is the most widely used treatment for solid-mass tumors worldwide. A contributing factor to tumor recurrence is the presence of residual tumor remaining at or near the surgical site following surgery. Goal: The primary objective of this study was to develop and evaluate an image-guided surgery system based on a near-infrared, handheld excitation source and spectrograph in combination with a widefield video imaging system. Methods: This system was designed to detect the fluorescence of near-infrared contrast agents and, in particular, indocyanine green (ICG). The imaging system was evaluated for its optical performance and ability to detect the presence of ICG in tumors in an ectopic murine tumor model as well as in spontaneous tumors arising in canines. Results: In both settings, an intravenous ICG infusion provided tumor contrast. In both the murine models and surgical specimens from canines, ICG preferentially accumulated in tumor tissue compared to surrounding normal tissue. The resulting contrast was sufficient to distinguish neoplasia from normal tissue; in the canine surgical specimens, the contrast was sufficient to permit identification of neoplasia on the marginal surface of the specimen. Conclusion: These results demonstrate a unique concept in image-guided surgery by combining local excitation and spectroscopy with widefield imaging. Significance: The ability to readily detect ICG in canines with spontaneous tumors in a clinical setting exemplifies the potential for further clinical translation; the promising results of detecting neoplasia on the marginal specimen surface underscore the clinical utility.

Detecting positive tumor margins and local malignant masses during surgery is critical for long-term patient survival. The use of image-guided surgery for tumor removal, particularly with near-infrared fluorescent imaging, is a potential method to facilitate removing all neoplastic tissue at the surgical site. In this study we demonstrate a series of hyaluronic acid (HLA)-derived nanoparticles that entrap the near-infrared dye indocyanine green, termed NanoICG, for improved delivery of the dye to tumors. Self-assembly of the nanoparticles was driven by conjugation of one of three hydrophobic moieties: aminopropyl-1-pyrenebutanamide (PBA), aminopropyl-5β-cholanamide (5βCA), or octadecylamine (ODA). Nanoparticle self-assembly, dye loading, and optical properties were characterized. NanoICG exhibited quenched fluorescence that could be activated by disassembly in a mixed solvent. NanoICG was found to be nontoxic at physiologically relevant concentrations and exposure was not found to inhibit cell growth. Using an MDA-MB-231 tumor xenograft model in mice, strong fluorescence enhancement in tumors was observed with NanoICG using a fluorescence image-guided surgery system and a whole-animal imaging system. Tumor contrast with NanoICG was significantly higher than with ICG alone.

Rationale and Objectives To evaluate whether the presence of facial photographs obtained at the point-of-care of portable radiography leads to increased detection of wrong-patient errors. Materials and Methods In this institutional review board–approved study, 166 radiograph–photograph combinations were obtained from 30 patients. Consecutive radiographs from the same patients resulted in 83 unique pairs (ie, a new radiograph and prior, comparison radiograph) for interpretation. To simulate wrong-patient errors, mismatched pairs were generated by pairing radiographs from different patients chosen randomly from the sample. Ninety radiologists each interpreted a unique randomly chosen set of 10 radiographic pairs, containing up to 10% mismatches (ie, error pairs). Radiologists were randomly assigned to interpret radiographs with or without photographs. The number of mismatches was identified, and interpretation times were recorded. Results Ninety radiologists with 21 ± 10 (mean ± standard deviation) years of experience were recruited to participate in this observer study. With the introduction of photographs, the proportion of errors detected increased from 31% (9 of 29) to 77% (23 of 30; P = .006). The odds ratio for detection of error with photographs to detection without photographs was 7.3 (95% confidence interval: 2.29–23.18). Observer qualifications, training, or practice in cardiothoracic radiology did not influence sensitivity for error detection. There is no significant difference in interpretation time for studies without photographs and those with photographs (60 ± 22 vs. 61 ± 25 seconds; P = .77). Conclusions In this observer study, facial photographs obtained simultaneously with portable chest radiographs increased the identification of any wrong-patient errors, without substantial increase in interpretation time. This technique offers a potential means to increase patient safety through correct patient identification.

We prospectively compared the ability of neuroradiologists to diagnose medulloblastoma with novice raters using only apparent diffusion coefficient (ADC) values measured on ADC maps. One hundred and three pediatric patients with pre-operative magnetic resonance imaging scans showing a posterior fossa tumor with histological verification were retrospectively identified from a ten-year period at a tertiary care medical center. A single observer measured the lowest ADC values in all tumors to determine the mean minimum ADC (ADCmin) value that provided greatest accuracy in distinguishing medulloblastomas from other tumors, which was determined to be 0.66×10−3 mm2/s. Imaging studies, including ADC maps, from 90 patients were provided to two neuroradiologists, who provided a diagnosis, which was later dichotomized as medulloblastoma or other. Two medical students measured ADCmin within tumors and those with ADCmin < 0.66×10−3 mm2/s were recorded as medulloblastoma; any other value was recorded as other. Diagnostic accuracy was measured. ADCmin values allowed a correct identification of lesions as either medulloblastoma or other in 91% of cases. After diagnoses by the two neuroradiologists were categorized as either medulloblastoma or other, their diagnoses were correct in 90% and 84% of cases, respectively. In 19 cases, at least one neuroradiologist was incorrect; the addition of ADC values to clinical interpretation would have allowed a correct diagnosis in 63% of such cases. Diagnostic accuracy based on ADC values by medical students was comparable to that of sub specialty-trained neuroradiologists. Our findings suggest that the addition of ADC values to standard film interpretation may improve the diagnostic rate for these tumors.

Objective Whether febrile status epilepticus (FSE) produces hippocampal sclerosis (HS) and temporal lobe epilepsy (TLE) has long been debated. Our objective is to determine if FSE produces acute hippocampal injury that evolves to HS.

Pompe disease is a lysosomal storage disorder caused by deficiency of acid-alpha glucosidase. There are limited data on central nervous system (CNS) involvement in survivors of infantile Pompe disease (IPD). The objective of this cross-sectional study is to implement the Fazekas scale, a visual MRI rating scale, to quantify white matter hyperintensities (WMH) on T2-weighted-Fluid Attenuated Inversion Recovery (T2-FLAIR) brain MRI images and to determine the extent of white matter (WM) involvement in the CNS of patients with IPD. Twelve patients (aged 6.1-18.1 years, 7 males, 5 females) with IPD and on long-term enzyme replacement therapy were included in the study. We assessed WM involvement in ten anatomical areas of the brain- juxtacortical U-fibers, subcortical WM, periventricular WM in the centrum semiovale and in the frontal and parietal lobes at the level of corona radiata, corpus callosum, anterior and posterior limb of the internal capsule, external capsule, corticospinal tracts at cerebral peduncles, midbrain, and pons and the medullary decussation of corticospinal tracts. Based on the severity of WMH, each area was graded on the Fazekas scale from zero (absent) to 3 (severe) and a total score (range 0-30) was obtained. Ten patients (ages 6.6-18.1 years) had WMH on brain MRI (range of scores: 2-23) using the Fazekas scale. Five of the 10 patients (ages 6.7-18.1 years) had scores greater than 15 (range 16-23) indicating severe WMH and 2/10 patients (aged 6.1 years and 7.3 years) had no WM involvement with a score of zero. Our results provide a means to quantify WM involvement in the CNS of patients with IPD. Fazekas scale could serve as a biomarker for longitudinal follow up of WM abnormalities in patients with IPD and to better understand the extent of CNS involvement in IPD. [A portion of this study was funded by Genzyme Sanofi]

Positron Emission Tomography (PET) is a medical imaging technique that can be used to show brain function. Courts have admitted PET scan evidence in cases involving brain damage, injury, toxic exposure, or illness ("brain trauma") and to support claims of diminished cognitive abilities and impulse control. Despite the limited data on the relationships between PET, brain trauma and behavior, many courts admit PET scan evidence without much critical analysis. This article examines the use of PET as proof of functional impairment and justification of abnormal behavior by explaining its diagnostic use and limitations, the limited support for claims of its relationship to behavior, and evidentiary considerations that should govern its admission into court as evidence. The authors urge courts to consider PET evidence, claims of experts, and the scope of the proposed testimony with greater deference to the clinical scope of PET, as outlined by the American College of Radiology's appropriateness criteria and the Working Group Report of the American Psychiatric Association.

This study examined the relationship between histological variables and diffusion tensor imaging (DTI) values in a normal canine brain. We hypothesized that radial diffusivity (RD) would correlate with myelin density and fractional anisotropy (FA) would correlate with white matter fiber coherence. We acquired DTI maps of a normal canine brain post mortem on a 7T MR scanner (TR = 100 ms, TE = 18.1 ms, NEX = 1, width [d] = 4 ms, separation [D] = 8.9 ms, gradient amplitude = 600 mT/m, b=1,565 s/mm2) and generated maps of FA, RD, and axial diffusivity. The brain was subsequently sectioned and stained for myelin with gold chloride, which also allowed for measurement of fiber coherence. DTI metrics were then directly compared with the optical density of the myelin stain and the coherence of stained fibers. Multivariate linear regression demonstrated that RD, but not FA, significantly correlated with both myelin stain intensity (p = 0.031) and fiber coherence (p = 0.035). The Pearson correlation coefficient between these two histological variables and FA was 0.122; and was 0.607 for the histological variables and RD. We found that RD significantly correlated with both optical density of myelinated fibers and fiber coherence, but FA correlated with neither histological finding. Factors other than degree of myelination and fiber coherence should be considered to fully account for regional variation in FA.

Metachromatic leukodystrophy (MLD) is an inherited demyelinating disease that causes progressive neurologic deterioration, leading to severe motor disability, developmental regression, seizures, blindness, deafness, and death. The disease presents as a late-infantile, juvenile, or adult form. Hematopoietic stem cell transplantation has been shown to slow disease progression. The purpose of this longitudinal study was to evaluate long-term treatment outcomes after unrelated donor umbilical cord blood (UCB) transplantation in pediatric patients according to disease burden and age at onset (ie, late-infantile versus juvenile). Engraftment, survival, treatment-related toxicity, graft-versus-host disease, neurophysiologic measures, and neurodevelopmental function were assessed. To evaluate whether signal intensity abnormalities on magnetic resonance imaging (ie, modified Loes scores) predict post-transplant cognitive and gross motor development, a general linear mixed model was fit to the data. Twenty-seven patients underwent transplantation after myeloablative chemotherapy; 24 patients engrafted after the initial transplantation. Seven patients died of infection, regimen-related toxicity, or disease progression. Twenty patients (6 with late-infantile onset and 14 with juvenile onset) were followed for a median of 5.1 years (range, 2.4 to 14.7). We found that patients with motor function symptoms at the time of transplant did not improve after transplantation. Brainstem auditory evoked responses, visual evoked potentials, electroencephalogram, and/or peripheral nerve conduction velocities stabilized or improved in juvenile patients but continued to worsen in most patients with the late-infantile presentation. Pretransplant modified Loes scores were highly correlated with developmental outcomes and predictive of cognitive and motor function. Children who were asymptomatic at the time of transplantation benefited most from the procedure. Children with juvenile onset and minimal symptoms showed stabilization or deterioration of motor skills but maintained cognitive skills. Overall, children with juvenile onset had better outcomes than those with late-infantile onset. As in other leukodystrophies, early intervention correlated with optimal outcomes. We conclude that UCB transplantation benefits children with presymptomatic late-infantile MLD or minimally symptomatic juvenile MLD.

We introduce the concept, benefits, and general architecture for acquiring, storing, and displaying digital photographs along with medical imaging examinations. We also discuss a specific implementation built around an Android-based system for simultaneously acquiring digital photographs along with portable radiographs. By an innovative application of radiofrequency identification technology to radiographic cassettes, the system is able to maintain a tight relationship between these photographs and the radiographs within the picture archiving and communications system (PACS) environment. We provide a cost analysis demonstrating the economic feasibility of this technology. Since our architecture naturally integrates with patient identification methods, we also address patient privacy issues.

The five questions answered in this article revolve around the different parameters resulting from perfusion imaging processing, and this clarifies the frequently confusing terminology used to describe these parameters. More specifically, the article discusses the different imaging techniques and main mathematical models behind perfusion imaging, reviews the perfusion attributes of brain tissue, and proposes a standardized parameter terminology to facilitate understanding and avoid common misinterpretations.

A 25% increase in bidimensional products (BPs) of tumor diameter has been used as a criterion for brain tumor progression. We studied intra-observer variability in measurements of BPs. Ten patients with contrast-enhancing glioblastoma multiforme underwent baseline and follow-up MR imaging. Seven observers measured BPs in various planes. Differences in BPs between scans were expressed as a percentage of baseline. This calculation was performed for both readings of the baseline and follow-up scans. Differences between change from baseline to follow-up on each reading (termed D values) were calculated for each reader (total of 196 D values). Median D value in each plane was calculated for each reader. Range of D values was 12.36–33.64% in axial plane (average 10.63%), 12.18–38.62% in coronal plane (average 26.84%) and 15.12–35.48% in sagittal plane (average 26.11%). Across all planes, 88 (45%) D values were >25%. When all imaging planes for any single observation were combined, in 76% of cases, at least one D value of >25% was seen. Based on the high degree of intra-observer variability, tumor measurements producing an increase in BP of >25% can routinely be obtained solely by chance.

The radiologist working in the emergency radiology setting is often faced with evaluating imaging findings of the patient whose chief complaint is that of the worst headache of life. The diagnosis of subarachnoid hemorrhage (SAH) is usually the initial consideration before imaging is performed and, appropriately, must be quickly diagnosed. However, a number of entities can simulate SAH on imaging studies. Those entities are presented here. In addition, a number of disease processes other than SAH can produce worst headache of life. Some of the most important entities, and their CT and MR findings, are reviewed here.

The purpose of the study was to determine the ability to predict infarct age based on decrease in apparent diffusion coefficient (ADC) values. We retrospectively identified 94 individuals (age range 16 years to 91 years; mean 63.7 + 14.1 years) who underwent magnetic resonance diffusion-weighted imaging at our institution over a course of 14 months whose infarct age could be reliably determined within 1 h. A single observer measured ADC values within the center of the infarct and compared them against values in contralateral normal tissue. We examined the ability of four ADC decrease thresholds (i.e.,50%,40%,30%, and20%) to predict infarct age of24 and48 h. Levels of ADC decrease in infarcts were as follows:20%, n = 9; 20-29%, n = 21; 30-39%, n = 25; 40-49%, n = 23;50%, n = 16. For prediction of infarct age24 h, sensitivity for the four ADC decrease thresholds ranged from 25% to 94%, specificity ranged from 10% to 85%, positive predictive value (PPV) ranged from 18% to 25%, and negative predictive value (NPV) ranged from 85% to 89%. For prediction of infarct age48 h, sensitivity ranged from 23% to 98%, specificity ranged from 15% to 87%, PPV ranged from 46% to 56%, and NPV ranged from 60% to 89%. Test performance characteristics for predicting infarct age of24 and48 h were relatively poor. In particular, PPV was very low for predicting infarcts24 h old.

The purpose of the study was to determine the frequency of various unenhanced computed tomography (CT) findings of early cerebral ischemia within brain parenchyma, which could be useful to the radiologist who is interpreting CT studies by indicating the CT finding that is most likely to be present in early cerebral ischemia. We analyzed articles reporting the use of unenhanced CT in acute cerebral ischemia over the period 1976-2009 for frequency of the following brain parenchyma signs: loss of insular ribbon, obscuration of lentiform nucleus, sulcal effacement, and parenchymal hypodensity. We recorded data for the 2-, 3-, 6-, and 12-h intervals after symptom onset from various studies and (1) calculated percent of time intervals in which >50% of patients exhibited the finding in any study and (2) pooled results for patients reported as having a specific CT finding during a specific time interval. We hypothesized that CT findings indicating brain swelling, which would be expected to be a relatively late phenomenon, would be detected at a lower rate in the first 6 h than changes of decreased density of brain tissue and increased density of arteries. The loss of insular ribbon sign (83% of time intervals reported) and obscuration of lentiform nucleus sign (75%) were the most common signs present in >50% patients in a time interval in any article. Pooled results showed that the two most common findings in the first few hours were loss of insular ribbon (70% at 2 h; 77% at 3 h) and obscuration of lentiform nucleus (60% at 2 h; 82% at 3 h). At 6 h, parenchymal hypodensity (53%), loss of insular ribbon (46%), and obscuration of lentiform nucleus (46%) were most common, which validated our hypothesis. At 12 h, loss of insular ribbon (65%) and sulcal effacement (63%) were most common. Loss of insular ribbon and obscuration of lentiform nucleus appear to be the most common signs of early cerebral ischemia identified on unenhanced CT.

Previous research suggests that, in reaction time (RT) measures of episodic memory retrieval, the unique effects of adult age are relatively small compared to the effects aging shares with more elementary abilities such as perceptual speed. Little is known, however, regarding the mechanisms of perceptual speed. We used diffusion tensor imaging (DTI) to test the hypothesis that white matter integrity, as indexed by fractional anisotropy (FA), serves as one mechanism of perceptual slowing in episodic memory retrieval. Results indicated that declines in FA in the pericallosal frontal region and in the genu of the corpus callosum, but not in other regions, mediated the relationship between perceptual speed and episodic retrieval RT. This relation held, though to a different degree, for both hits and correct rejections. These findings suggest that white matter integrity in prefrontal regions is one mechanism underlying the relation between individual differences in perceptual speed and episodic retrieval.

Convection-enhanced delivery (CED) is a novel drug delivery technique that uses positive infusion pressure to deliver therapeutic agents directly into the interstitial spaces of the brain. Despite the promise of CED, clinical trials have demonstrated that target-tissue anatomy and patient-specific physiology play a major role in drug distribution using this technique. In this study, we retrospectively tested the ability of a software algorithm using MR diffusion tensor imaging to predict patient-specific drug distributions by CED. A tumor-targeted cytotoxin, cintredekin besudotox (interleukin 13–PE38QQR), was coinfused with iodine 123–labeled human serum albumin (123I-HSA), in patients with recurrent malignant gliomas. The spatial distribution of 123I-HSA was then compared to a drug distribution simulation provided by the software algorithm. The algorithm had a high sensitivity (71.4%) and specificity (100%) for identifying the high proportion (7 of 14) of catheter trajectories that failed to deliver drug into the desired anatomical region ( p = 0.021). This usually occurred when catheter trajectories crossed deep sulci, resulting in leak of the infusate into the subarachnoid cerebrospinal fluid space. The mean concordance of the volume of distribution at the 50% isodose level between the actual 123I-HSA distribution and simulation was 65.75% (95% confidence interval [CI], 52.0%–79.5%), and the mean maximal in-plane deviation was less than 8.5 mm (95% CI, 4.0–13.0 mm). The use of this simulation algorithm was considered clinically useful in 84.6% of catheters. Routine use of this algorithm, and its further developments, should improve prospective selection of catheter trajectories, and thereby improve the efficacy of drugs delivered by this promising technique.

BackgroundOrbitofrontal cortex (OFC) volumetric differences have been reported in depression, but in relatively small samples. Factors associated with these differences are not well described. We examined OFC volumes in a large sample of elderly depressed and non-depressed subjects, exploring the relationship between OFC volume, 5HTTLPR genotype, apolipoprotein E (APOE) genotype and hyperintense lesion volume. We hypothesized that smaller OFC volume would be associated with depression, greater hyperintense lesion volume and severity, and APOE ε4 or 5HTTLPR short allele carriers.MethodA total of 226 depressed and 144 non-depressed older subjects completed 1·5 T magnetic resonance imaging (MRI) and genotyping. OFC volumes and lesion volumes were measured using standardized methods. Lesion severity was additionally rated using the Coffey rating scale. Differences between groups were compared while controlling for age, sex and total cerebral volume; separate models added lesion measures and genetic polymorphisms.ResultsDepressed subjects exhibited smaller OFC volumes. There was a trend for a negative association between white-matter lesion volume and OFC volume; however, rated white-matter lesion severity was significantly negatively associated with OFC volume. There was no association between gray-matter lesion measures or 5HTTLPR genotype and OFC volume. Contrary to our hypothesis, subjects who were APOE ε4 allele positive exhibited larger OFC volumes; in secondary analyses, this finding was limited to the non-depressed group.ConclusionsReduced OFC volumes are seen in depression and associated with greater severity of white-matter lesions. Healthy subjects who are APOE ε4 allele positive exhibited larger OFC volumes. This finding should be examined in other populations.

We combined measures from event-related functional magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI), and cognitive performance (visual search response time) to test the hypotheses that differences between younger and older adults in top-down (goal-directed) attention would be related to cortical activation, and that white matter integrity as measured by DTI (fractional anisotropy, FA) would be a mediator of this age-related effect. Activation in frontal and parietal cortical regions was overall greater for older adults than for younger adults. The relation between activation and search performance supported the hypothesis of age differences in top-down attention. When the task involved top-down control (increased target predictability), performance was associated with frontoparietal activation for older adults, but with occipital (fusiform) activation for younger adults. White matter integrity (FA) exhibited an age-related decline that was more pronounced for anterior brain regions than for posterior regions, but white matter integrity did not specifically mediate the age-related increase in activation of the frontoparietal attentional network.

A wide variety of imaging findings can be seen in the setting of acute head trauma. The purpose of this manuscript is to review the major computed tomography and magnetic resonance imaging findings of various types of traumatic head injuries with the intent of providing the reader with a means to diagnose these lesions quickly and accurately.

Neuroimaging research suggests that cerebral white matter (WM) integrity, as reflected in fractional anisotropy (FA) via diffusion tensor imaging (DTI), is decreased in older adults, especially in the prefrontal regions of the brain. Behavioral investigations of cognitive functioning suggest that some aspects of cognition may be better preserved in older adults who possess higher levels of aerobic fitness. There are only a few studies, however, investigating potential mechanisms for the improvements in aerobic fitness. Our study suggests that greater aerobic fitness may be related to greater WM integrity in select brain regions.

Magnetic resonance (MR) imaging plays an increasingly important role in evaluation of the patient who has sustained spinal trauma. This review discusses the role of MR imaging relative to plain radiographs and computed tomography in the evaluation of the patient with spinal trauma and presents a method for systematic review of MR images for assessing spinal injury.

The central nervous system undergoes profound and predictable developmental changes during the first few years of life that provide the structural and functional elements necessary for normal neurological development. The establishment and maturation of white matter pathways is a critical component of the developing nervous system. Diffusion tensor imaging (DTI) offers a noninvasive and quantitative means for the evaluation of white matter changes. DTI has contributed to the evaluation of a number of childhood leukoencephalopathies; it has also been used to follow brain maturation in abnormal states, such as premature birth or early brain injury. Furthermore, it has helped characterize the relation between white matter integrity and cognitive abilities. In the future, DTI is expected to play an increasingly large role in defining developmental abnormalities at an early age and in assessing therapies for pediatric disorders such as leukodystrophies.

Purpose To assess the efficacy and toxicity of intraresection cavity iodine-131–labeled murine antitenascin monoclonal antibody 81C6 (131I-m81C6) among recurrent malignant brain tumor patients. Patients and Methods In this phase II trial, 100 mCi of 131I-m81C6 was injected directly into the surgically created resection cavity (SCRC) of 43 patients with recurrent malignant glioma (glioblastoma multiforme [GBM], n = 33; anaplastic astrocytoma [AA], n = 6; anaplastic oligodendroglioma [AO], n = 2; gliosarcoma [GS], n = 1; and metastatic adenocarcinoma, n = 1) followed by chemotherapy. Results With a median follow-up of 172 weeks, 63% and 59% of patients with GBM/GS and AA/AO tumors were alive at 1 year. Median overall survival for patients with GBM/GS and AA/AO tumors was 64 and 99 weeks, respectively. Ten patients (23%) developed acute hematologic toxicity. Five patients (12%) developed acute reversible neurotoxicity. One patient (2%) developed irreversible neurotoxicity. No patients required reoperation for radionecrosis. Conclusion In this single-institution phase II study, administration of 100 mCi of 131I-m81C6 to recurrent malignant glioma patients followed by chemotherapy is associated with a median survival that is greater than that of historical controls treated with surgery plus iodine-125 brachytherapy. Furthermore, toxicity was acceptable. Administration of a fixed millicurie dose resulted in a wide range of absorbed radiation doses to the SCRC. We are now conducting a phase II trial, approved by the US Food and Drug Administration, using patient-specific 131I-m81C6 dosing, to deliver 44 Gy to the SCRC followed by standardized chemotherapy. A phase III multicenter trial with patient-specific dosing is planned.

Purpose We performed a phase II study to evaluate the combination of imatinib mesylate, an adenosine triphosphate mimetic, tyrosine kinase inhibitor, plus hydroxyurea, a ribonucleotide reductase inhibitor, in patients with recurrent glioblastoma multiforme (GBM). Patients and Methods Patients with GBM at any recurrence received imatinib mesylate plus hydroxyurea (500 mg twice a day) orally on a continuous, daily schedule. The imatinib mesylate dose was 500 mg twice a day for patients on enzyme-inducing antiepileptic drugs (EIAEDs) and 400 mg once a day for those not on EIAEDs. Assessments were performed every 28 days. The primary end point was 6-month progression-free survival (PFS). Results Thirty-three patients enrolled with progressive disease after prior radiotherapy and at least temozolomide-based chemotherapy. With a median follow-up of 58 weeks, 27% of patients were progression-free at 6 months, and the median PFS was 14.4 weeks. Three patients (9%) achieved radiographic response, and 14 (42%) achieved stable disease. Cox regression analysis identified concurrent EIAED use and no more than one prior progression as independent positive prognostic factors of PFS. The most common toxicities included grade 3 neutropenia (16%), thrombocytopenia (6%), and edema (6%). There were no grade 4 or 5 events. Concurrent EIAED use lowered imatinib mesylate exposure. Imatinib mesylate clearance was decreased at day 28 compared with day 1 in all patients, suggesting an effect of hydroxyurea. Conclusion Imatinib mesylate plus hydroxyurea is well tolerated and associated with durable antitumor activity in some patients with recurrent GBM.

Hyperintense lesions in both white matter and gray matter on T2-weighted magnetic resonance imaging (MRI) are associated with late-life depression. This large study examined differences in gray and white matter lesion volumes on brain MRI between 253 elderly depressed and 146 control subjects. White matter and gray matter lesion volumes were measured in each hemisphere using a semi-automated segmentation process and compared against depression status. Depressed subjects exhibited significantly greater total white matter (mean 7.22 ml) and gray matter (mean 0.30 ml) lesion volumes in both hemispheres than did control subjects (mean 4.87 ml in white matter and 0.18 ml in gray matter). This difference remained statistically significant even after controlling for confounders such as age, sex, race and reports of hypertension, diabetes and heart disease. Patients with late-life depression have larger white matter lesion and gray matter lesion volumes than do control subjects. Future research should combine similar volumetric techniques with methods of identifying the location of lesions specific to late-life depression.

Rationale and objectives We sought to quantify patient preferences for mild, moderate, and severe low back pain via time-tradeoff analysis and utility measurement. Materials and methods Forty-one patients being treated for low back pain in a tertiary care teaching hospital participated in the study. Patients were asked to decide which of three health states they were currently experiencing as well as which of the three health states was the worst experienced during their lifetime. A time-tradeoff analysis was performed, during which patients were asked the amount of time in each of the health states they would exchange for complete resolution of symptoms. We correlated (1) subjects’ current health state with reported utility and (2) degree of previous low back pain with results of time-tradeoff measurements. Results All patients were willing to trade a greater number of life-years for resolution of symptoms given a more severe perceived health state. Utility decreased as severity of back pain scenarios increased, with an average utility of 0.93 ± 0.11 for mild, 0.65 ± 0.21 for moderate, and 0.18 ± 0.17 for severe pain. No significant difference in time-tradeoff among subjects was identified based upon current health state on the day of interview. A statistically significant difference was seen in patients’ willingness to trade time among those who had actually experienced severe pain versus those who had not. Kendall’s correlation revealed that subjects who had experienced severe back pain exhibited significantly lower utilities (P Conclusions As expected, patients with severe low back pain were willing to sacrifice more potential years of life for resolution of symptoms, suggesting time-tradeoff can accurately reflect patient utility. 2. However, we found no correlation between a subject’s current health state and reported utility.

Objective: In this study, we examined 204 older depressed individuals for up to 64 months to determine factors related to depression outcome. We hypothesized that both presence of vascular brain lesions seen on baseline magnetic resonance imaging (MRI) scans and lower baseline social support measures would be related to worse depression outcome.Method: At study entry, all subjects were at least 59 years old, had a diagnosis of major depression, and were free of other major psychiatric illness and primary neurological illness, including dementia and stroke. Depression was diagnosed via structured interview and clinical assessment by a geriatric psychiatrist who completed a Montgomery Asberg Depression Rating Scale (MADRS) to determine severity of depression. Subjects provided self-report data on social support variables and ability to perform basic and instrumental activities of daily living (ADL, IADL). All subjects agreed to have a baseline standardized MRI brain scan. Ratings of severity of hyperintensities were determined for the periventricular white matter, deep white matter, and subcortical gray matter by two readers who decided by consensus. Treatment was provided by geropsychiatrists following clinical guidelines. Using mixed models to analyze the data, we determined the effect of a variety of demographic, social and imaging variables on the trajectory of MADRS score, the outcome variable of interest.Results: MADRS scores decreased steadily over time. In a final HLM model, in which time since entry, a baseline time indicator, age, gender, education and Mini-mental State Examination score were controlled, subjective social support, instrumental ADL impairment, subcortical gray matter severity, and the interactions of time with social network and with subcortical gray matter lesions remained significantly associated with MADRS score.Conclusions: Both social and biological factors at baseline are associated with longitudinal depression severity in geriatric depression.

In preclinical studies, BCNU, or 1,3-bis(2-chloroethyl)-1-nitrosourea, plus CPT-11 (irinotecan) exhibits schedule-dependent, synergistic activity against malignant glioma (MG). We previously established the maximum tolerated dose of CPT-11 when administered for 4 consecutive weeks in combination with BCNU administered on the first day of each 6-week cycle. We now report a phase 2 trial of BCNU plus CPT-11 for patients with MG. In the current study, BCNU (100 mg/m2) was administered on day 1 of each 6-week cycle. CPT-11 was administered on days 1, 8, 15, and 22 at 225 mg/m2 for patients receiving CYP3A1- or CYP3A4-inducing anticonvulsants and at 125 mg/m2 for those not on these medications. Newly diagnosed patients received up to 3 cycles before radiotherapy, while recurrent patients received up to 8 cycles. The primary end point of this study was radiographic response, while time to progression and overall survival were also assessed. Seventy-six patients were treated, including 37 with newly diagnosed tumors and 39 with recurrent disease. Fifty-six had glioblastoma multiforme, 18 had anaplastic astrocytoma, and 2 had anaplastic oligodendroglioma. Toxicities (grade > or =3) included infections (13%), thromboses (12%), diarrhea (10%), and neutropenia (7%). Interstitial pneumonitis developed in 4 patients. Five newly diagnosed patients (14%; 95% CI, 5%-29%) achieved a radiographic response (1 complete response and 4 partial responses). Five patients with recurrent MG also achieved a response (1 complete response and 4 partial responses; 13%; 95% CI, 4%-27%). More than 40% of both newly diagnosed and recurrent patients achieved stable disease. Median time to progression was 11.3 weeks for recurrent glioblastoma multiforme patients and 16.9 weeks for recurrent anaplastic astrocytoma/ anaplastic oligodendroglioma patients. We conclude that the activity of BCNU plus CPT-11 for patients with MG appears comparable to that of CPT-11 alone and may be more toxic.

Previous studies have shown a reduction of orbital frontal cortex volume and an increase in magnetic resonance imaging signal hyperintensities in geriatric depression. We aimed to assess the relationship between subcortical gray- and deep white-matter lesions and orbital frontal cortex volume in elderly depressives and controls. The study included 41 elderly depressed patients and 41 age-matched control subjects. The orbital frontal cortex volume was measured in both hemispheres using a standardized MRI procedure. Signal hyperintensities were rated on (T2)-weighted MRI with qualitative lesion analyses performed according to an established hyperintensity classification system. After controlling for total cerebral hemisphere, age and sex, the geriatric depressed subjects had significant reduction in orbital frontal cortex volume and compared with the control group. Multiple linear regression modeling indicated that reduced orbital frontal cortex volumes were significantly associated with increased subcortical gray-matter lesions. Our study confirmed the reduction of OFC volume in geriatric depressed subjects. We also suggest that subcortical lesions may decrease OFC volume. Further studies are needed to understand how subcortical lesions may be related to OFC volume changes.

We report dynamic CT perfusion imaging assessment of hemodynamics in a patient with a high-grade cerebral glioma and compare our results to those of previously published studies.

Purpose: We evaluated the usefulness of a treatment regimen that included high-dose chemotherapy (HDC) with autologous stem-cell rescue (ASCR) in patients with newly diagnosed pineoblastoma (PBL). Patients and Methods: Twelve patients with PBL were initially treated with surgery and induction chemotherapy. All but two patients underwent radiotherapy. Subsequently, all patients received HDC using cyclophosphamide (CTX) + melphalan (MEL) or busulfan (Bu) + MEL regimens and ASCR. Results: A total of six children and six adults with median ages of 4.2 (range, 0.3 to 19.8 years) and 23 years (range, 23 to 43.7 years), respectively, were treated according to this strategy. Four patients had metastatic disease confined to the neuraxis. Five of 12 patients (42%) had a complete tumor resection at diagnosis. Ten patients received radiotherapy at median doses of 36.0 and 59.4 Gy to the neuraxis and pineal region, respectively. Eleven patients received HDC with CTX + MEL, and one patient received BU + MEL followed by ASCR. Nine patients are alive with no evidence of disease recurrence at a median of 62 months from diagnosis (range, 28 to 125 months), including three patients with metastatic disease and two infants who did not receive any radiotherapy. Three patients have died of progressive disease at 19, 32, and 37 months from diagnosis, respectively. The actuarial 4-year progression-free and overall survivals are 69% (95% confidence interval [CI], 39% to 99%) and 71% (95% CI, 43% to 99%), respectively. Conclusion: The use of HDC in addition to radiotherapy seems to be an effective treatment for patients with newly diagnosed pineoblastoma.

Edaravone, a novel free radical scavenger, demonstrates neuroprotective effects by inhibiting vascular endothelial cell injury and ameliorating neuronal damage in ischemic brain models. The present study was undertaken to verify its therapeutic efficacy following acute ischemic stroke. We performed a multicenter, randomized, placebo-controlled, double-blind study on acute ischemic stroke patients commencing within 72 h of onset. Edaravone was infused at a dose of 30 mg, twice a day, for 14 days. At discharge within 3 months or at 3 months after onset, the functional outcome was evaluated using the modified Rankin Scale. Two hundred and fifty-two patients were initially enrolled. Of these, 125 were allocated to the edaravone group and 125 to the placebo group for analysis. Two patients were excluded because of subarachnoid hemorrhage and disseminated intravascular coagulation. A significant improvement in functional outcome was observed in the edaravone group as evaluated by the modified Rankin Scale (p = 0.0382). Edaravone represents a neuroprotective agent which is potentially useful for treating acute ischemic stroke, since it can exert significant effects on functional outcome as compared with placebo.

While several studies are available on the immediate effects of marijuana and its active ingredient tetrahydrocannabinol (THC) on regional cerebral blood flow (rCBF), we examined the effects of intravenous infusion of THC on rCBF and behavior over a 120-min. period using positron emission tomography. Indices of rCBF, intoxication and physiology were measured at baseline and 30, 60, 90 and 120 min. after a 20-min. intravenous infusion of 0.15 or 0.25 mg/min. of THC, or placebo given to 47 subjects. The rCBF remained increased up to 120 min. after the high-dose THC infusion. Significant increases were seen in global perfusion and in the frontal, insular and anterior cingulate regions. Changes were greater in the right hemisphere. After the high dose, cerebellar flow was increased at both 30 and 60 min. The anterioposterior ratio of cortical rCBF increased in both hemispheres, and remained significantly greater than in the placebo condition until 120 min. in the right hemisphere. Intoxication peaked at 30 min. and remained elevated at 120 min. THC had significant effects on global CBF and rCBF, and feeling intoxicated accounted for changes in rCBF better than plasma level of THC.

Advances in the immunohistochemical detection of neuron-specific and neuronal-associated antigens have resulted in the discovery of neuronal elements in certain primary human brain tumors. The results have been not only to expand what neuropathologists commonly recognize as gangliogliomas, including the tumors now known as glioneurocytic tumor with neuropil rosettes and papillary ganglioneuroma, but also to expand the spectrum of tumor types to now include tumors such as central neurocytoma, dysembryoplastic neuroepithelial tumor, and desmoplastic infantile ganglioglioma. These discoveries have helped us to better understand the biology of these tumors and to refine our classification of them. Distinctions among these tumors include sites of predilection, such as the temporal lobe with the dysembryoplastic neuroepithelial tumors, and a spectrum of clinical aggressiveness that spans indolent "quasi-hamartomatous" lesions, such as the dysembryoplastic neuroepithelial tumor, to high-grade, highly aggressive tumors, such as the supratentorial primitive neuroectodermal tumor (World Health Organization Grade IV). Many of these tumors also commonly exhibit a glial component, as determined by both their histologic appearance and their immunoreactivity for glial fibrillary acidic protein. This review covers these recently described lesions, including the desmoplastic infantile ganglioglioma, the dysembryoplastic neuroepithelial tumor, the papillary glioneuronal tumor, the glioneuronal tumor with neuropil rosettes, and the mixed glioblastoma-cerebral neuroblastoma (supratentorial primitive neuroectodermal tumor), as well as the known tumors, ganglioglioma, medulloepithelioma, and medulloblastoma. For pathologists confronted by this growing array of tumors and subtypes, it is appropriate to focus on them and understand the differential diagnosis to be considered when confronted by them.

The combination of high signal and reduced apparent diffusion coefficients (ADC) within abscesses on diffusion-weighted MRI (DWI) has been reported as characteristic of abscesses, and useful for distinguishing them from cystic or necrotic neoplasms. To assess whether these are consistent findings in abscesses, we used DWI-derived ADC to investigate changes in water diffusibility in cerebral abscesses. We reviewed the MRI studies and clinical records of five patients with brain abscesses, who underwent DWI. Regions of interest were drawn within the abscesses on ADC maps, to obtain the ADC. The center of all five abscesses gave signal higher than that of white matter on DWI. The three largest also appeared bright on ADC maps, i. e., showed ADC substantially lower than those of normal white matter, consistent with restricted diffusion. However, the two smaller abscesses were not visible on ADC maps because their ADC were essentially the same as that of white matter; they did not show restricted diffusion. The absence of restricted diffusion within small abscesses may be related to intrinsic differences in molecular microenvironment between small and large abscesses, or to greater influence of volume averaging with surrounding edema on the ADC in smaller abscesses.

Previously reported methods of dynamic, contrast-enhanced, CT perfusion imaging in acute stroke have been promising but substantially limited by their dependence on very rapid rates of injection (typically 10-20 ml/s in an arm vein). Newly available deconvolution software permits the use of lower rates of injection (e. g., 3-4 ml/s), and rapidly provides maps of cerebral blood flow, cerebral blood volume and mean transit time. We report the potential of CT perfusion imaging performed with an injection rate of 4 ml/s to provide information on the extent of hemodynamic abnormality, and to help distinguish viable from nonviable ischemic tissue. The slower injection rates permitted by deconvolution analysis substantially enhance the practicality of CT perfusion imaging for studying stroke.

The objective of the two pivotal phase 3 studies was to evaluate the safety and efficacy of OptiMARK (Gd-DTPA-bis(methoxyethylamide) [Gd-DTPA-BMEA]) compared with Magnevist (Gd-DTPA) in magnetic resonance imaging of the central nervous system.Two multicenter, randomized, double-blind, parallel group studies were conducted in 395 patients with known or suspected central nervous system pathology. Subjects were randomized to receive a single 0.1 mmol/kg intravenous injection of either Gd-DTPA-BMEA or Gd-DTPA. The safety of Gd-DTPA-BMEA and Gd-DTPA was monitored for up to 72 hours after study drug administration. Precontrast and postcontrast administration magnetic resonance scans were acquired using identical imaging planes and techniques.No deaths or unexpected adverse events were reported in either group. A comparison of adverse events by intensity and relation demonstrated no statistically significant differences between the two groups. Gd-DTPA-BMEA and Gd-DTPA were equivalent with respect to confidence in diagnosis, conspicuity, and border delineation.Gd-DTPA-BMEA and Gd-DTPA demonstrated comparable efficacy profiles, and the safety profiles were considered similar.

Magnetic resonance (MR) of the central nervous system has few, but important indications for use in the acute setting. This report reviews the few true current clinical indications for emergency MR imaging, including ruling out spinal cord compression, vascular dissection or dural venous sinus thrombosis. Possible indications for emergency MR, including evaluation of acute stroke symptomatology, potential meningoencephalitis or vasculitis, are also presented. Future applications for MR, including MR angiography in the setting of acute subarachnoid hemorrhage and spectroscopy in acute ischemia, are mentioned.

Positron Emission Tomography (PET) is a medical imaging technique that can be used to show brain function. Courts have admitted PET scan evidence in cases involving brain damage, injury, toxic exposure, or illness ("brain trauma") and to support claims of diminished cognitive abilities and impulse control. Despite the limited data on the relationships between PET, brain trauma and behavior, many courts admit PET scan evidence without much critical analysis. This article examines the use of PET as proof of functional impairment and justification of abnormal behavior by explaining its diagnostic use and limitations, the limited support for claims of its relationship to behavior, and evidentiary considerations that should govern its admission into court as evidence. The authors urge courts to consider PET evidence, claims of experts, and the scope of the proposed testimony with greater deference to the clinical scope of PET, as outlined by the American College of Radiology's appropriateness criteria and the Working Group Report of the American Psychiatric Association.

Objective Our aim was to determine the frequency with which a lesion responsible for hemiballismus was detectable on CT and MR examinations. Materials and methods The CT and MR examinations of six patients with hemiballismus were reviewed. Three patients underwent MRI alone, two CT alone, and one underwent both CT and MRI. Sites considered as possible locations for a lesion causing hemiballismus included the subthalamic nucleus on the side contralateral to the movements, contralateral putamen, caudate nucleus, thalamus, corpus striatum, lenticular nucleus, substantia nigra, and the premotor and motor cortex. Results A lesion likely to account for hemiballismus was found in five patients (contralateral subthalamic nucleus in four patients, contralateral putamen in one patient). Causes of hemiballismus included infarction (one patient), hemorrhage (two patients), trauma (one patient), and an abscess (one patient). A responsible lesion was detected in all five patients who underwent MRI. In one patient who underwent CT alone, a responsible lesion was not identified. Conclusion A lesion responsible for hemiballistic movements can generally be found on cross-sectional imaging examinations. Because the multiplanar imaging capability of MR appears to allow for sensitive detection of even small lesions in sites likely to cause hemiballismus, MRI offers the best means of imaging these patients.

Objective: Our goal was to characterize the CT and MR features of supratentorial ependymomas and subependymomas. Materials and Methods: The CT or MRI examinations of 11 supratentorial ependymomas (average patient age: 16 years) and 3 supratentorial subependymomas (average age: 60 years) were analyzed for tumor size, location, and appearance. Results: Ependymomas were periventricular (nine), intraventricular (one), or both (one) and averaged 4 cm in diameter. Four of nine ependymomas examined by CT were calcified. Eight ependymomas had a cystic component. All seven ependymomas evaluated with MRI demonstrated prolonged T1 and T2 relaxation, with two having foci thought to represent intratumoral hemorrhage. The MR contrast enhancement patterns included an enhancing nodule within the wall of a cyst (four), heterogeneous enhancement of cystic/solid lesions (two), and homogeneous enhancement of a solid lesion (one). All subependymomas were solid intraventricular masses, averaging 2.6 cm in diameter. One had small amounts of calcification, and none were cystic. All three were isointense or hypointense to white matter on Tl-weighted MR images and heterogeneous or hyperintense on T2-weighted images, with variable enhancement characteristics. Early (< year) postsurgical recurrence was seen in two ependymomas and one subependymoma. Conclusion: Supratentorial ependymomas are typically large, cystic, calcified, extraventricular masses found in children and young adults. Supratentorial subependymomas are generally solid, intraventricular masses that are usually smaller than ependymomas and occur in an older patient population.

Objective Our goal was to demonstrate the spectrum of neuroradiologic (CT, MR, and angiographic) findings in craniocervical arterial dissection (CAD) related to exercise or sporting activities and compare the diagnostic utility of CT, MRI, and MR angiography (MRA). Materials and methods The neuroradiologic examinations of 11 patients with CAD was performed: CT was performed in 10 patients, cranial MRI in 9, cranial and cervical MRA in 4, and contrast angiography in 10. The CT examinations were assessed for the presence of an infarction or a hyperdense artery (consistent with intraluminal thrombus), MRI examinations for the presence of infarction or abnormal periarterial signal, and contrast angiograms for arterial stenosis or occlusion, luminal irregularity, pseudoaneurysm, intimal flap, or distal branch occlusions. Results Computed tomography demonstrated infarction in four patients. At contrast angiography, a dissection was found in the artery supplying the region of infarction in all cases. A hyperdense artery was found by CT in two patients, which correlated with dissection of the artery or its parent artery on contrast angiography. Cranial MRI findings were seen in six patients (infarction in five, periarterial signal abnormality in five). Dissection was confirmed in all four patients with abnormal periarterial signal who underwent contrast angiography. Two patients with abnormal intracranial periarterial signal had corresponding abnormalities on MRA. False-negative cranial and cervical MRI and MRA studies were performed in one patient because the imaging volumes used for the cervical and intracranial MR examinations did not overlap. Four patients with normal intracranial arterial signal had dissection in the neck demonstrated by contrast angiography. Conclusion Neuroradiologic findings of CAD can include infarction, a hyperdense artery on CT, abnormal periarterial signal on MRI, and a narrowed arterial signal column on MRA. Computed tomography is an insensitive screening examination. Proper use of MRI and MRA involves examination of both the head and the neck with overlapping imaging volumes of the two regions.

Contrast angiography is the standard means of diagnosing spinal dural arteriovenous fistulas. We present a patient in whom a spinal dural arteriovenous fistula was demonstrated on phase contrast MR angiography.