The effect of risperidone on metabolite measures in the frontal lobe, temporal lobe, and thalamus in schizophrenic patients. A proton magnetic resonance spectroscopy (1H MRS)

OBJECTIVE

The aim of the study was the evaluation of risperidone effect on metabolite measures in the frontal lobe, temporal lobe and thalamus in schizophrenic patients on the basis of proton magnetic resonance spectroscopy ( (1)H MRS).

METHODS

A group of 14 patients with the diagnosis of schizophrenia, according to DSM-IV, were examined in the study. The patients were examined twice, once after a period of at least 7 days without neuroleptics and for the second time at least 4 weeks after stable risperidone doses.

RESULTS

The significant differences in the metabolite levels before and after the treatment were observed only in thalamus: an increase in myoinositol (mI) and N-acetylaspartate (NAA) levels. Positive symptoms before the treatment correlated positively with NAA level in the frontal lobes and negatively in the temporal lobes. Negative symptoms before the treatment correlated positively with Glx (a common signal for GABA, glutamine and glutamate) level in the temporal lobes.

CONCLUSION

Our results seem to confirm the influence of risperidone on the brain metabolism, specifically in the region of thalamus.

Osteochondral defects of the talus treated by mesenchymal stem cell implantation--early results

The purpose of this study was to present early results of talus cartilage defects treatment with autologous mesenchymal stem cells CD34+ implantation technique. Nine (9) patients were treated, due to IV degree chondromalation (by ICRS). The applied standard procedure included: clinical examination, AP and lateral x-ray, MRI, preoperative, as well as during control examination. The surgical procedure consisted of the defect's debridement, harvesting and fixation of the periosteal flap and CD34+ implantation. Clinical results were assessed after 6 months to 3 years by clinical examination, Magee score and MRI. Good and very good clinical results were obtained and confirmed by MRI in 8 cases. In one case, cartilage hypertrophy was noted. There were no delamination and infection signs.

Cerebral MR spectroscopy in neurologically asymptomatic HIV-infected patients

PURPOSE

To detect early metabolic changes in the brain of neurologically asymptomatic HIV-infected patients with normal MR imaging and to find the correlation between 1H MR results and immune status.

MATERIAL AND METHODS

Twenty neurologically asymptomatic HIV seropositive patients underwent MR imaging and single-voxel 1H MR spectroscopy (MRS) using a PRESS sequence. For all patients, the signals from N-acetyl-aspartate (NAA), choline-containing compounds (Cho), creatine-phosphocreatine (Cr) and myoinositol (mI) were compared with 32 healthy volunteers as metabolite ratios and metabolite areas to non-suppressed water area ratios.

RESULTS

In HIV patients, the NAA/Cho ratio was significantly lower ( p < 0.01), but there were no changes in NAA/Cr ratio. A statistically significant reduction in NAA/H2O and Cr/H2O (both p < 0.05) was observed. For the immune status there was a statistically significant correlation (r=0.47, p<0.05) between CD4 counts and NAA/H2O ratio. A significant increase in Cho/Cr ( p<0.001) and mI/Cr ( p<0.01) ratios in HIV patients was found, but Cho/H2O and mI/H2O concentrations were non-significantly increased.

CONCLUSION

These results indicate that neuronal loss and gliosis in HIV-infected patients may be associated with impairment of energy metabolism. The spectral changes found suggest that 1H MRS can be used for early detection of brain damage induced by HIV.

Cerebral MR spectroscopy in neurologically asymptomatic HIV-infected patients

PURPOSE

To detect early metabolic changes in the brain of neurologically asymptomatic HIV-infected patients with normal MR imaging and to find the correlation between 1H MR results and immune status.

MATERIAL AND METHODS

Twenty neurologically asymptomatic HIV seropositive patients underwent MR imaging and single-voxel 1H MR spectroscopy (MRS) using a PRESS sequence. For all patients, the signals from N-acetyl-aspartate (NAA), choline-containing compounds (Cho), creatine-phosphocreatine (Cr) and myoinositol (mI) were compared with 32 healthy volunteers as metabolite ratios and metabolite areas to non-suppressed water area ratios.

RESULTS

In HIV patients, the NAA/Cho ratio was significantly lower ( p < 0.01), but there were no changes in NAA/Cr ratio. A statistically significant reduction in NAA/H2O and Cr/H2O (both p < 0.05) was observed. For the immune status there was a statistically significant correlation (r=0.47, p<0.05) between CD4 counts and NAA/H2O ratio. A significant increase in Cho/Cr ( p<0.001) and mI/Cr ( p<0.01) ratios in HIV patients was found, but Cho/H2O and mI/H2O concentrations were non-significantly increased.

CONCLUSION

These results indicate that neuronal loss and gliosis in HIV-infected patients may be associated with impairment of energy metabolism. The spectral changes found suggest that 1H MRS can be used for early detection of brain damage induced by HIV.

[Magnetic resonance proton spectroscopy in neurooncology--preliminary report]

MR proton spectroscopy (1H MRS) has been widely applied in characterisation and differentiation of brain tumors, staging, recurrence of pathologic process, post radiotherapy changes and other lesions mimicking neoplasm like abscesses. Despite of many studies performed over last 3 years in many countries spectroscopic pattern (phenotype) of brain tumors is still not well estimated and the role of each metabolite as an indicator of histopathologic grade and type of the tumor is still unknown.

MATERIALS AND METHODS

In vivo 1H MR spectroscopy was prospectively performed in 36 patients with intracranial tumors (low grade gliomas, high grade gliomas, meningiomas and abscesses). Examinations was performed with 1.5 T system, using voxels of 8 cc.

RESULTS

In high grade gliomas level of NAA was decreased, and consequently low ratios of NAA to other metabolites were obtained; lactate and choline peaks were markedly increased. In patients with meningiomas signal of NAA was reduced, while in abscesses group peaks of acetate and succinate were observed. Authors analysed ratios of metabolites in above-mentioned tumors. The method is especially useful in differential diagnosis in neoplastic and nonneoplastic cases.

CONCLUSIONS

Our study confirms diagnostic value of 1H MRS in doubtful cases of intracranial tumors.