Investigation of corpus callosum in schizophrenia with diffusion imaging.

BACKGROUND: Corpus callosum (CC) is the main white matter commissure between the two cerebral hemispheres. Abnormalities of CC have been shown in schizophrenia patients by magnetic resonance imaging (MRI) studies. We here further investigated CC organization with diffusion imaging (DWI) in a sample of schizophrenia patients recruited from the epidemiologically defined catchment area of South Verona, Italy. METHODS: Sixty-seven patients with schizophrenia and 70 normal controls were studied. Regions of interests (ROIs), standardized at 5 pixels, were placed in CC on the non-diffusion weighted echoplanar images (b = 0) and were then automatically transferred to the corresponding maps to obtain the apparent diffusion coefficient (ADC) of water molecules. RESULTS: ADC measures for all callosal subregions in schizophrenia patients were significantly greater compared to normal controls (ANCOVA, p < 0.05). Positive symptoms significantly correlated with anterior callosal ADC measures (partial correlation analyses, p < 0.05). CONCLUSIONS: These findings support the existence of widespread microstructure disruption of CC in schizophrenia, which may ultimately lead to inter-hemispheric misconnection, and also suggest a specific role of anterior transcallosal disconnectivity in underlying positive symptoms. Future longitudinal MRI studies in high risk and first-episode patients together with neurophysiological tests are indicated to further examine CC anatomical abnormalities and inter-hemispheric transmission in schizophrenia.

Percutaneous CT-guided vertebroplasty in the management of osteoporotic fractures and dorsolumbar metastases.

Percutaneous vertebroplasty (PVP) is a minimally invasive, image-guided procedure consisting of an injection of acrylic cement into a vertebral body to reinforce the compressed segment and achieve pain relief. The use of PVP is a minimally invasive option in the treatment of osteoporotic or metastatic vertebral collapses. Our personal experience, using a CT-guided technique, confirms the efficacy and safety of PVP with a lower risk for complications compared with conventional fluoroscopic approaches because of a precise placement of the instruments in the vertebral body and an early detection of small cement leakages.

MRI versus scintigraphy with 99mTc-HMPAO-labelled granulocytes in the diagnosis of bone infection.

PURPOSE: To assess the reliability of MRI and scintigraphy with 99mTc-HMPAO-labelled granulocytes in the diagnosis of bone infection. MATERIALS AND METHODS: Between November 2001 and November 2003, 25 patients (16 men and 9 women; age range 22-72 years; mean age 48 years) with suspected bone infection were evaluated. The lower limbs were more frequently involved (20/25 cases). MRI (T1 and T2-w sequences, both with and without fat suppression; T1-w fat-suppressed sequence after Gadolinium administration) and scintigraphy with 99mTc-HMPAO-labelled granulocytes were performed in all patients; the study was performed 30 min, 150 min and 24 h after the injection of 99mTc labelled autologous granulocytes. The maximum interval between MRI and scintigraphy was 15 days. The diagnosis was confirmed surgically (18/25 cases) or by clinical follow-up (7/25 cases). RESULTS: In 10/25 cases the clinical suspicion of bone infection was confirmed by MRI, scintigraphy and surgery. In 12/25 cases the clinical suspicion of bone infection was not confirmed either by imaging, surgery (5/12 cases) or follow-up (7/12 cases). In 3/25 cases the results were discordant: in 1/3 cases with chronic osteomyelitis confirmed by MRI and surgery, a false-negative diagnosis was made by scintigraphy. In 2/3 cases with negative MRI diagnoses confirmed by surgery, a false-positive diagnosis was made by scintigraphy owing to the infection of adjacent soft tissues. CONCLUSIONS: MRI is more reliable for the detection and evaluation of the local spread of bone infection. Conversely, when metallic devices causing artefacts on MR images are present, scintigraphy is the preferred alternative modality.