Calcified cerebral emboli.

Intracranial calcifications may represent calcified cerebral emboli. Calcified emboli may be overlooked even though cerebral CT is widely used as a stroke assessment. We report 4 cases of calcified cerebral emboli and demonstrate the value of CT in the diagnosis and temporal evaluation of such emboli.

Temporal lobe abnormalities in multigenerational families with schizophrenia.

Brain structure in familial schizophrenia was studied with computerized tomography in 42 individuals from six multigenerational families. Sulcal enlargement in the lateral temporal cortex, and ventricular and cisternal enlargement in the medial temporal region were observed in psychotic individuals compared to unaffected family members. Genetic factors in familial schizophrenia may exert part of their effect through determining or altering temporal lobe structure.

Obstetric complications and age-related changes in brain morphology in schizophrenia.

Birth problems can lead to changes in brain morphology in the general population and an increased prevalence of both birth problems and altered brain morphology are found in patients with schizophrenia. The purpose of this study was to test the hypothesis that these two findings are related. Birth history and the size of ventricular and sulcal spaces from nine regions of the brain were assessed in 80 male subjects with schizophrenia. No differences were found between patients with and those without a history of birth problems for the size of any brain space; however, ventricular size increased significantly with age in patients who had no birth complications but not in patients with a history of birth problems. The size of cortical sulci increased with age in patients with and those without a history of birth problems. These results suggest that region-specific rates of change in size may identify clinically meaningful patients subgroups.

Long-term follow-up after cerebral hemispherectomy: neurophysiologic, radiologic, and psychological findings.

Eight patients were studied 3 to 16 years (mean, 10 years) after cerebral hemispherectomy. Seven have infantile hemiplegia, and one had Sturge-Weber disease. Preoperative assessment included EEG responses to intracarotid drug injections. Postoperative complications occurred in seven patients. The operation was followed by a marked reduction in seizure frequency and improvement in behavior, with little change in intellect or hemiplegia. Neuropsychological assessment performed in four patients showed that they were not aphasic, but nonverbal spatial abilities were poor. CT showed marked shift of the remaining hemisphere in five of six patients scanned.

Language dominance: correlation of radiological and functional data.

Morphological asymmetry of the posterior sylvian region was measured in carotid arteriograms of patients with medically refractory seizures. Anatomical asymmetry correlated with ear superiority on dichotic listening tests.

Regional cortical anatomy and clozapine response in refractory schizophrenia.

Regional measures of cortical sulcal and ventricular enlargement on computed tomography scan were studied in a clinical sample of patients treated with clozapine. Cortical sulci were significantly enlarged in clozapine nonresponders compared to responders. The Clinical Global Impressions score at discharge was related to the size of the posterior frontal and lateral temporal sulci, with large sulci predicting a poorer response to clozapine treatment.

Clinical experience with Hexabrix in cerebral angiography.

Sixty patients from the University of British Columbia, Vancouver General Hospital, and University of Alberta Hospitals Edmonton participated in an open-labelled clinical study on the safety, tolerability and efficacy of ioxaglic acid (Hexabrix) in cerebral angiography. Only 4% of patients experienced significant pain during carotid and brachiocephalic injections of Hexabrix. No increased incidence of side effects or adverse effects were encountered. In addition, radiographic film quality overall was excellent and comparable to that obtained using conventional contrast agents. Hexabrix is a safe and effective contrast agent for cerebral angiography.

Left cerebral hemiatrophy and schizophrenia-like psychosis in an adolescent.

A previous report of cerebral hemiatrophy and schizophrenia added to the list of neurodevelopmental abnormalities associated with schizophrenia. In a new case, the birth history indicated perinatal hemorrhage and prematurity (30-31 weeks of gestation). CT and MR imaging showed reduction in left hemisphere size with ventricular enlargement and mild skull thickening. Loss of periventricular white matter was detected. Changes in skull thickness, size of air cells and volume of the cranial vault may be measurable correlates of putative developmental abnormalities in schizophrenia.

The temporal lobes, reversed asymmetry and the genetics of schizophrenia.

Mechanisms determining temporal lobe structural asymmetries may be involved in the pathogenesis of schizophrenia. To investigate the temporal lobes in familial schizophrenia, computed tomographic scans were obtained from 51 subjects (seven families). Enlargement of sylvian fissures and temporal lobe sulcal spaces was observed in family members with schizophrenia. The posterior one-third of the sylvian fissure was larger on the left side in subjects with schizophrenia, and larger on the right side in unaffected individuals. This disturbed pattern of posterior sylvian fissure asymmetry suggests that adjacent language regions may be affected in schizophrenia. An intermediate degree of disturbance in subjects who had schizophrenia-related illnesses or were obligate carriers suggests that genetic factors may be important determinants of temporal lobe asymmetries in familial schizophrenia.

Acute subdural hematomas: atypical CT findings.

Seventy-one patients with acute subdural hematomas were examined by CT within 72 hr of a documented head injury. Lesions often did not have the classical appearance of a homogeneous, high-density extracerebral collection of blood in a crescentic configuration. Specifically, 28 patients (39%) had mixed-density subdural hematomas (MDSDH) with various degrees of low-density blood within the subdural space. In 10 of these 28 patients, the hematoma had a relatively localized mass effect with a convex inner margin, occasionally mimicking the appearance of an epidural hematoma. The MDSDH group differed from the typical homogeneous high-density subdural hematomas in that they were larger (average maximal thickness was 18.1 mm versus 8.0 mm), had more midline shift, and had a higher mortality rate (50% versus 26%). Four patients with MDSDH demonstrated an unusual pattern of ventricular compression with trapping of cerebrospinal fluid in the body of the ipsilateral ventricle and compression of the body of the contralateral ventricle. This pattern has to our knowledge not been previously described. Possible causes of the low-density regions within the hematomas include unclotted blood in an early stage of hematoma development, serum extruded during the early phase of clot retraction, or cerebrospinal fluid within the subdural space due to an arachnoid tear.

Orbital dermoids: clinical presentation and management.

The authors have reviewed 15 cases of orbital dermoids representing 6% of orbital tumours seen at the University of British Columbia Orbital Clinic. They tended to occur as either asymptomatic superficial lesions in children or as complicated deep lesions in adolescents and adults. The superficial lesions were as frequent medially as laterally and could be dealt with by a direct uncomplicated surgical approach. The deep lesions in contrast, were frequently extensive and difficult to remove, requiring careful preoperative planning. Sites of origin, presentation, differential diagnosis, and management are discussed.

White matter tract abnormalities in first-episode psychosis.

Fibers connecting fronto-temporal and fronto-medial structures that pass through the anterior limb of the internal capsule (ALIC) subserve executive and psychomotor functioning. Both of these functions are adversely affected in schizophrenia, and may be abnormal at illness onset. In a study of first-episode psychosis, we used diffusion tensor imaging (DTI) and cognitive testing to examine ALIC integrity. Fourteen early psychosis patients and 29 healthy volunteers were included. Symptoms were assessed with the Positive and Negative Syndromes Scale (PANSS). All structural and diffusion scans were acquired on a GE Signa 1.5T scanner. A T1-weighted 3D FSPGR Inversion Recovery imaging series was acquired for manual seeding in structural space. Diffusion tensor imaging (DTI) was performed, and all DTI images were co-registered to structural space. Seeds were manually drawn bilaterally on the coronal plane at a specified location. Diffusion images were post-processed for subsequent Tract-based Spatial Statistics (TBSS) analysis. First-episode psychosis patients had significantly smaller fronto-medial and fronto-temporal AIC tract volumes compared to healthy volunteers on the left and the right (p-values<0.04). No differences in mean fractional anisotropy (FA) were seen within either left or right tracts (p-values>0.05), nor did TBSS reveal any other differences in FA values between groups in other regions. Relationships between tract volumes and symptom severity were not observed in this study.

Diffusion-weighted imaging findings in Balo concentric sclerosis.

Balo concentric sclerosis is a rare demyelinating disease. Pathognomonic features have been previously described. Diffusion-wighted imaging findings have not been previously described in Balo concentric sclerosis. We describe the diffusion-weighted imaging findings in a 45-year-old lady with Balo concentric sclerosis. Diffusion-weighted imaging offers insight into the possible pathophysiology of this rare disease.

Spinal epidural abscess: unusual CT and microbiologic findings.

The incidence of spinal epidural abscess is increasing. Its expeditious diagnosis is essential if treatment is to be effective. The authors present a case in which both the computed tomography appearance and the microbiologic observations were unusual.

Acute orbital pseudotumors: classification and CT features.

Acute orbital pseudotumors are inflammatory lesions of unknown etiology that may affect part or, less often, all of the tissue within the orbit. A retrospective computed tomographic (CT) study of 16 patients demonstrated that these lesions occur in one of five specific anatomic patterns: anterior, posterior, diffuse, lacrimal, or myositic. The most common location was lacrimal followed by anterior pseudotumors. Posterior, most common location was lacrimal followed by anterior pseudotumors. Posterior, diffuse, and myositic pseudotumors were equally frequent. Localization on the basis of clinical features correlated with the CT localization. Illustrative cases of each of the five types are included. The role of CT in evaluating the therapeutic response is discussed.

Computed tomography of a cerebellopontine angle lipoma.

In this report we document the clinical, radiologic, surgical, and pathologic features of a cerebellopontine angle (CPA) lipoma, including the CT visualization of the seventh and eighth cranial nerves passing through the middle of the lesion, a feature previously undescribed. Comparison is made with other reported CPA lipomas.

Value of intravenous contrast enhancement in the CT evaluation of intraspinal tumors.

The usefulness of intravenous contrast-enhanced CT in delineating intraspinal cord tumors has not been well documented. To determine if intradural spinal tumors enhance, if the location and type of tumor can be determined, and if a double dose of contrast material provides more information than a single dose, a retrospective study of 23 patients with proven intradural extramedullary or intramedullary tumors was performed. All the tumors studied with CT after intravenous contrast enhancement showed that most lesions (18/23) enhanced, contrary to published reports. Contrast-enhanced studies delineated the extent of the tumor, helping to separate solid and cystic components. The enhancement pattern of ependymomas and astrocytomas was similar, while schwannomas had a characteristic appearance. A double dose of intravenous contrast material had no apparent advantage over a single dose.

A case study of temporal lobe development in familial schizophrenia.

Case studies of patients with familial schizophrenia may help to define the pathophysiology of this illness and indicate potential candidate genes for genetic linkage studies. In this regard, the clinical, radiological and pathological assessments of a 39-year-old affected man from a pedigree with familial schizophrenia are presented. Brain imaging with CT indicated moderate cortical atrophy, particularly of the temporal lobes. Neuropathological examination revealed granular ependymitis, indicating possible past ventricular pathology. Granular ependymitis was reported to occur in genetic developmental disorders with neuronal migration abnormalities. In the present case, heterotopic clusters of neurons were visualized in the entorhinal cortex, suggesting that temporal lobe development was not entirely normal. This case study suggests that genetic factors could be investigated further as one possible aetiology of certain neurodevelopmental abnormalities observed in schizophrenia.