Positive symptoms and white matter microstructure in never-medicated first episode schizophrenia

BACKGROUND

We investigated cerebral structural connectivity and its relationship to symptoms in never-medicated individuals with first-onset schizophrenia using diffusion tensor imaging (DTI).

METHOD

We recruited subjects with first episode DSM-IV schizophrenia who had never been exposed to antipsychotic medication (n=34) and age-matched healthy volunteers (n=32). All subjects received DTI and structural magnetic resonance imaging scans. Patients' symptoms were assessed on the Positive and Negative Syndrome Scale. Voxel-based analysis was performed to investigate brain regions where fractional anisotropy (FA) values significantly correlated with symptom scores.

RESULTS

In patients with first-episode schizophrenia, positive symptoms correlated positively with FA scores in white matter associated with the right frontal lobe, left anterior cingulate gyrus, left superior temporal gyrus, right middle temporal gyrus, right middle cingulate gyrus, and left cuneus. Importantly, FA in each of these regions was lower in patients than controls, but patients with more positive symptoms had FA values closer to controls. We found no significant correlations between FA and negative symptoms.

CONCLUSIONS

The newly-diagnosed, neuroleptic-naive patients had lower FA scores in the brain compared with controls. There was positive correlation between FA scores and positive symptoms scores in frontotemporal tracts, including left fronto-occipital fasciculus and left inferior longitudinal fasciculus. This implies that white matter dysintegrity is already present in the pre-treatment phase and that FA is likely to decrease after clinical treatment or symptom remission.

White matter fractional anisotrophy differences and correlates of diagnostic symptoms in autism

BACKGROUND

Individuals with autism have impairments in 3 domains: communication, social interaction and repetitive behaviours. Our previous work suggested early structural and connectivity abnormalities in prefrontal-striato-temporal-cerebellar networks but it is not clear how these are linked to diagnostic indices.

METHOD

Children with autism (IQ > 70) aged 6 to 14 years old and matched typically developing controls were studied using diffusion tensor imaging. Voxel-based methods were used to compare fractional anisotrophy (FA) measures in each group and to correlate FA measures in the autism group with the diagnostic phenotype described by the Autism Diagnostic Interview - Revised (ADI-R) algorithm for ICD-10.

RESULTS

After controlling for the effects of age and white matter volume, we found that FA in the autism group was significantly lower than controls in bilateral prefrontal and temporal regions, especially in the right ventral temporal lobe adjacent to the fusiform gyrus. FA was greater in autism in the right inferior frontal gyrus and left occipital lobe. We observed a tight correlation between lower FA and higher ADI-R diagnostic algorithm scores across white matter tracts extending from these focal regions of group difference. Communication and social reciprocity impairments correlated with lower FA throughout fronto-striato-temporal pathways. Repetitive behaviours correlated with white matter indices in more posterior brain pathways, including splenium of the corpus callosum and cerebellum.

CONCLUSIONS

Our data support the position that diagnostic symptoms of autism are associated with a core disruption of white matter development.

A diffusion tensor imaging study of structural dysconnectivity in never-medicated, first-episode schizophrenia

BACKGROUND

Diffusion tensor imaging (DTI) can be used to investigate cerebral structural connectivity in never-medicated individuals with first-episode schizophrenia.

METHOD

Subjects with first-episode schizophrenia according to DSM-IV-R who had never been exposed to antipsychotic medication (n=25) and healthy controls (n=26) were recruited. Groups were matched for age, gender, best parental socio-economic status and ethnicity. All subjects underwent DTI and structural magnetic resonance imaging (MRI) scans. Voxel-based analysis was performed to investigate brain regions where fractional anisotropy (FA) values differed significantly between groups. A confirmatory region-of-interest (ROI) analysis of FA scores was performed in which regions were placed blind to group membership.

RESULTS

In patients, FA values significantly lower than those in healthy controls were located in the left fronto-occipital fasciculus, left inferior longitudinal fasciculus, white matter adjacent to right precuneus, splenium of corpus callosum, right posterior limb of internal capsule, white matter adjacent to right substantia nigra, and left cerebral peduncle. ROI analysis of the corpus callosum confirmed that the patient group had significantly lower mean FA values than the controls in the splenium but not in the genu. The intra-class correlation coefficient (ICC) for independent ROI measurements was 0.90 (genu) and 0.90 (splenium). There were no regions where FA values were significantly higher in the patients than in the healthy controls.

CONCLUSIONS

Widespread structural dysconnectivity, including the subcortical region, is already present in neuroleptic-naive patients in their first episode of illness.

Alpha-thalassaemia in association with beta-thalassaemia patients in Malaysia: a study on the co-inheritance of both disorders

BACKGROUND/AIMS

Individuals with double heterozygosity for alpha- and beta-thalassaemia and heterozygous beta-thalassaemia show a similar haematological picture. Co-inheritance of alpha- and beta-thalassaemia in both partners may result in pregnancies with either Hb Bart's hydrops foetalis or beta-thalassaemia major, or pregnancies with both disorders.

METHODS

The co-inheritance of alpha-thalassaemia in 322 beta-thalassaemia carriers in Malaysia was studied.

RESULTS

The frequency of alpha-thalassaemia in the beta-thalassaemia carriers was 12.7% (41/322), with a carrier frequency of 7.8% for the SEA deletion, 3.7% for the -alpha(3.7) deletion, 0.9% for Hb Constant Spring and 0.3% for the -alpha(4.2) deletion.

CONCLUSION

Double heterozygosity for alpha- and beta-thalassaemia was confirmed in 5 out of the 41 couples and the risk of the fatal condition Hb Bart's hydrops foetalis was confirmed in two of these couples. Detection of the Southeast Asian (SEA) deletion in the Malaysian Malays in this study confirms that Hb Bart's hydrops foetalis can occur in this ethnic group. Results of this study have provided new information on the frequency and different types of alpha-thalassaemia (--(SEA), -alpha(3.7) and -alpha(4.2) deletions, Hb Constant Spring) in Malaysian beta-thalassaemia carriers.

Intramedullary spinal schwannoma: case report and review of preoperative magnetic resonance imaging features

Intramedullary schwannomas are rare spinal cord tumours. Correct preoperative diagnosis is essential for proper surgical planning and complete resection. We present a case of cervical intramedullary schwannoma followed by discussion on its preoperative magnetic resonance imaging features and review of the literature.

Patient with Leriche's syndrome and concomitant superior mesenteric aneurysm: Evaluation with contrast-enhanced three-dimensional magnetic resonance angiography, computed tomography angiography and digital subtraction angiography

Conventional angiography is regarded as the gold standard in vascular imaging but it is invasive, and difficulty may be encountered in the evaluation of aortic occlusion disease. Superior mesenteric artery aneurysm is an uncommon disease, which can result in life-threatening haemorrhage after rupture. With the rapid development of computed tomography angiography (CTA) and magnetic resonance angiography (MRA), high-quality images of the vascular system can be obtained in a non-invasive manner. We report a case of Leriche's syndrome with concomitant superior mesenteric aneurysm using contrast-enhanced 3-D CTA and MRA, with digital subtraction angiography correlation.

Mapping the brain in autism. A voxel-based MRI study of volumetric differences and intercorrelations in autism

Autism is a disorder of neurodevelopment resulting in pervasive abnormalities in social interaction and communication, repetitive behaviours and restricted interests. There is evidence for functional abnormalities and metabolic dysconnectivity in 'social brain' circuitry in this condition, but its structural basis has proved difficult to establish reliably. Explanations for this include replication difficulties inherent in 'region of interest' approaches usually adopted, and variable inclusion criteria for subjects across the autism spectrum. Moreover, despite a consensus that autism probably affects widely distributed brain regions, the issue of anatomical connectivity has received little attention. Therefore, we planned a fully automated voxel-based whole brain volumetric analysis in children with autism and normal IQ. We predicted that brain structural changes would be similar to those previously shown in adults with autism spectrum disorder and that a correlation analysis would suggest structural dysconnectivity. We included 17 stringently diagnosed children with autism and 17 age-matched controls. All children had IQ >80. Using Brain Activation and Morphological Mapping (BAMM) software, we measured global brain and tissue class volumes and mapped regional grey and white matter differences across the whole brain. With the expectation that volumes of interconnected regions correlate positively, we carried out a preliminary exploration of 'connectivity' in autism by comparing the nature of inter-regional grey matter volume correlations with control. Children with autism had a significant reduction in total grey matter volume and significant increase in CSF volume. They had significant localized grey matter reductions within fronto-striatal and parietal networks similar to findings in our previous study, and additional decreases in ventral and superior temporal grey matter. White matter was reduced in the cerebellum, left internal capsule and fornices. Correlation analysis revealed significantly more numerous and more positive grey matter volumetric correlations in controls compared with children with autism. Thus, using similar diagnostic criteria and image analysis methods in otherwise healthy populations with an autistic spectrum disorder from different countries, cultures and age groups, we report a number of consistent findings. Taken together, our data suggest abnormalities in the anatomy and connectivity of limbic-striatal 'social' brain systems which may contribute to the brain metabolic differences and behavioural phenotype in autism.

Tumor volume is not an independent prognostic factor in early-stage nasopharyngeal carcinoma treated by radiotherapy alone

PURPOSE

To determine whether the tumor volume can predict the treatment outcome in early-stage nasopharyngeal carcinoma (NPC) treated by radiotherapy alone.

METHODS AND MATERIALS

The pretreatment CT scans of 116 patients with American Joint Committee on Cancer Stage I-II NPC treated by radiotherapy alone were retrospectively reviewed. The clinician outlined the tumor extent. The primary tumor volume (PTV) and nodal volume (NV) were then calculated by a summation-of-areas technique. The PTV and NV were correlated with locoregional control, distant failure, and survival. The median follow-up time was 105 months.

RESULTS

Patients with Stage I disease had a 5-year locoregional control rate of 95% and a disease-specific survival (DSS) rate of 97%; for Stage II disease, the corresponding rates were 81% and 79%. The PTV ranged from 1.3 to 75.5 cm3 (median, 12.6 cm3), with substantial overlap between T1 and T2 disease. The NV ranged from 0 to 35.4 cm(3). Patients with a PTV >15 cm3 had significantly worse local control (5-year control rate, 82% vs. 93%; p = 0.033), but no statistically significant difference was noted in survival (5-year DSS rate, 83% vs. 89%; p = 0.30). The difference in local control was mainly seen in those with T2 disease. Patients with NV >4 cm3 had a greater distant failure rate (5-year distant metastasis-free rate, 72% vs. 90%; p = 0.011) and worse survival (5-year DSS rate, 76% vs. 94%; p = 0.0038). Nodal control was excellent with no difference between a NV of < or =4 cm3 and a NV of >4 cm3 (5-year control rate, 97% vs. 100%). The survival rate was worst in patients with a PTV >15 cm3 and a NV >4 cm3 (5-year DSS rate, 68%) and best in those with a PTV of < or =15 cm3 and a NV of < or =4 cm3 (5-year DSS rate, 92%). Multivariate analysis, however, showed that only parapharyngeal extension (T2b) and N1 stage were independent factors that predicted locoregional control and survival, and N1 stage was the only factor that predicted distant failure.

CONCLUSION

The pretreatment tumor volume has a limited prognostic value in early-stage NPC compared with the usual T and N classification, with Stage T2b and N1 as independent factors that predicted treatment outcome. Within T2 disease, the estimation of tumor volume may identify a subgroup of patients with a greater risk of local failure that warrants more aggressive treatment.

Imaging features of focal intrahepatic extramedullary haematopoiesis

The imaging findings of focal intrahepatic extramedullary haematopoiesis (EMH) in a 51-year-old woman with beta-thalassaemia intermedia are described with particular reference to MRI and CT. Bone marrow colloid scintigraphy was unhelpful in confirming the diagnosis, which was made from fine needle aspiration. This is the first description of stellate scars occurring in an EMH lesion. A review of the radiological appearances of this rare condition is presented.

Renal metastasis from choriocarcinoma: MRI appearance

Choriocarcinoma is the most malignant tumor of gestational trophoblastic neoplasia. It grows rapidly and metastasizes to the lung, liver, and, less frequently, to the brain. Renal involvement is rare. Magnetic resonance imaging (MRI) is a useful modality to image the affected tissues; it contributes to the evaluation and management of the disease. One case of renal choriocarcinoma with MRI evaluation is reported.

Volumetric analysis of tumor extent in nasopharyngeal carcinoma and correlation with treatment outcome

PURPOSE

To investigate the variability of tumor volume in nasopharyngeal carcinoma using quantitative measurements of tumor bulk derived from computed tomography, and to study the prognostic value of tumor volume in comparison with other variables.

METHODS AND MATERIALS

Two hundred ninety patients with newly diagnosed nasopharyngeal carcinoma were included in the study. The primary tumor volume (PTV) and nodal tumor volume (NTV) were obtained by outlining the tumor contour followed by summation of areas in sequential pretreatment computed tomography axial scans. Total tumor volume (TTV) was obtained by adding the PTV and NTV. All patients had radiotherapy as the primary treatment, 67 patients also received cisplatin-based neoadjuvant chemotheraphy.

RESULTS

A large variation in tumor volume was observed, especially in advanced stage disease. The median PTV (cc) in Ho's T1, T2, and T3 disease were: 6.9 (range: 0.9-42.7), 18.8 (1.6-127.9), and 52.4 (3.3-166.8). The median TTV (cc) in Ho's stage I to IV disease were: 7.6 (range: 1.3-42.7), 19.8 (3.2-55.7), 40.7 (4.1-222.7), and 51.1 (3.1-274.7). Patients with a large PTV (>60 cc) were associated with significantly poorer local control (5-year local control rate: 56%) and disease-specific survival (5-year survival rate: 53%). In patients with a small PTV (< or =20 cc), there were no significant differences in local control among different T stages. Large NTV (>30 cc) was associated with significantly higher distant failure rate (5-year distant relapse-free survival rate: 54%) and lower disease-specific survival (5-year survival rate: 40%). In multivariate analysis, only PTV was found to be an independent factor in predicting local control.

CONCLUSION

A large variation of tumor volume was present in different T stage disease of nasopharyngeal carcinoma, and PTV represents an independent prognostic factor of local control that appears to be more predictive than Ho's T stage classification.

The effect of somatostatin versus corticosteroid in the treatment of Graves' ophthalmopathy

Uncontrolled study has demonstrated the usefulness of somatostatin in the treatment of mild Graves' ophthalmopathy (GO). We performed a prospective study to evaluate the usefulness of somatostatin as compared to corticosteroid in the treatment of moderately severe GO. All patients were rendered euthyroid and observed for 3 months to exclude spontaneous improvement without active treatment. They were randomized to receive either somatostatin (SS, octreotide 200 micrograms q8h subcutaneously, n = 8) or corticosteroid (CS, prednisone 1 mg/kg/day in decreasing doses, n = 10). Assessments of soft tissue inflammation, exophthalmos, palpebral aperture, intraocular pressure, diplopia, cornea, and visual acuity were made every 4 weeks for 3 months. MRI of the orbit was performed before and after treatment. Both SS and CS therapy decreased the palpebral aperture and activity score after 3 months (p < 0.05), but those treated with CS had a lower activity score after treatment when compared to SS [2.5 (1-7) v.s. 3.5 (0-4), median (range), p < 0.05]. Only CS, but not SS, was able to reduce intraocular pressure and muscle size as documented by MRI, but no significant reduction in proptosis was observed in either group. Also, patients' self-assessments of the eye changes after treatment were similar between the two groups. Both groups showed significant elevation of urinary glycosaminoglycan (GAG) excretion before therapy (SS 24.6 +/- 10.8; CS 27.8 +/- 11.4 mg/24 h), which was reduced after treatment (SS 12.5 +/- 7.3; CS 10.8 +/- 6.3 mg/24 h, p < 0.05). However, no significant correlation could be observed between the degree of GAG reduction and the clinical outcome of the patients. In conclusion, the long acting SS octreotide was effective in reducing soft tissue inflammation and providing symptomatic relief in GO but not as effective as corticosteroid in reducing muscle size. In view of the minimal side-effects and similar efficacy as compared to corticosteroid in patients with minimal extraocular muscle enlargement, it is suggested that a trial of SS may be considered in selected patients with GO.

Hypertransfusion for spinal cord compression secondary to extramedullary hematopoiesis

A 19-year-old girl with thalassemia intermedia presented with signs of thoracic spinal cord compression secondary to extramedullary hematopoiesis. She was started on a transfusion regimen to maintain a hemoglobin level of more than 12.5 g/dL. Clinical signs disappeared within the first week and circulating erythroblastemia was completely suppressed by the second week. Magnetic resonance imaging 4 weeks after diagnosis revealed near-complete resolution of the extradural mass, followed by gradual improvement in the posterior tibial somatosensory evoked potentials. Transfusion therapy may be diagnostically and therapeutically useful in spinal cord compression secondary to extramedullary hematopoiesis, obviating the need for surgery or radiotherapy.

Magnetic resonance imaging of cerebrotendinous xanthomatosis

Cerebrotendinous xanthomatosis is a rare familial sterol storage disease with accumulation of cholestanol and cholesterol particularly in xanthomas, bile and brain. Magnetic resonance imaging is a useful modality for imaging the affected tissues. It contributes to the evaluation and management of the disease.

An outbreak of epidemic polyarthritis (Ross River virus disease) in the Northern Territory during the 1990-1991 wet season

OBJECTIVE

To describe the epidemiology of a large outbreak of epidemic polyarthritis in the Northern Territory during the wet season of 1990-1991.

DESIGN, SETTING AND PARTICIPANTS

Arbovirus cases notified to the Northern Territory Department of Health and Community Services by general practitioners and local laboratories between 1 July 1990 and 30 June 1991.

MAIN OUTCOME MEASURES

Date and place of infection, age, sex and symptoms.

RESULTS

Doctors in the Northern Territory notified 368 cases; another 14 were infected interstate. The epidemic started in September, peaked in January and tailed off in April. The highest attack rates occurred in the rural areas of Jabiru, Litchfield Shire and Katherine. Those most affected were 30-34 year olds. Children, the elderly and Aboriginal people were under-represented.

CONCLUSIONS

Epidemic polyarthritis is a wet season problem in the Northern Territory, affecting the rural towns and districts more than the cities. Pre-planned mosquito control measures (effective water drainage and larval control) limited the extent of the 1990-1991 epidemic in Darwin City and Palmerston. The low attack rate in children reflects asymptomatic and less clinically severe infections. The under-representation of Aboriginal people may be the result of infection occurring earlier in life. A related cross-sectional seroprevalence survey has shown that rural Aboriginal people across all age groups have a significantly higher seropositive rate than urban non-Aboriginal residents.