Corpus Callosotomy for Drug-Resistant Schizophrenia; Novel Treatment Based on Pathophysiology

Neuroanatomical comparison of treatment-resistant and treatment-responsive schizophrenia patients using the cloud-based brain magnetic resonance image segmentation and parcellation system: An MRIcloud study

Recent developments in neuroimaging have improved our understanding of the biological mechanisms underlying schizophrenia. However, neuroimaging findings in treatment-resistant schizophrenia (TRS) remain unclear. In the present study, we aimed to explore potential neuroanatomical regions that may be associated with treatment resistance in schizophrenia patients by comparing neuroanatomical regions of TRS and non-TRS patients using the MRICloud method. A total of 33 schizophrenia patients (meeting DSM 5 diagnostic criteria for schizophrenia) were included in the study. Patients were dichotomized into TRS (n = 18) and non-TRS (n = 15) groups, and all patients underwent MRI. Neuroanatomical regions of TRS and non-TRS patients were compared using the MRICloud method. Disease severity was measured using the Positive and Negative Syndrome Scale (PANSS). Interestingly, a statistically significant greater left Corpus Collosum (CC) thickness was found in TRS patients compared to non-TRS patients. It is clear that further studies comparing TRS patients with non-TRS patients are needed, and these studies should focus on the circuits in the corpus callosum that are thought to play a role in treatment resistance. Further longitudinal studies are also needed to complement the cross-sectional studies, using a multimodal imaging approach in the patients with clearly defined TRS criteria.

Aberrant interhemispheric structural and functional connectivity within whole brain in schizophrenia

OBJECTIVE

Schizophrenia is a serious mental disorder whose etiology remains unclear. Although numerous studies have analyzed the abnormal gray matter functional activity and whole-brain anatomical changes in schizophrenia, fMRI signal fluctuations from white matter have usually been ignored and rarely reported in the literature.

METHODS

We employed 45 schizophrenia subjects and 75 healthy controls (HCs) from a publicly available fMRI dataset. By combining the voxel-mirrored homotopic connectivity (VMHC) measure and fiber tracking method, we investigated the interhemispheric functional and structural connectivity within whole brain in schizophrenia.

RESULTS

Compared to HCs, patients with schizophrenia exhibited significantly reduced VMHC in the bilateral middle occipital gyrus, precentral gyrus, postcentral gyrus and corpus callosum. Fiber tracking results showed the changes in structural connectivity for the bilateral precentral gyrus, and the bilateral corpus callosum, and the fiber bundles connecting bilateral precentral gyrus and connecting the bilateral corpus callosum passed through the posterior midbody, isthmus and splenium of mid-sagittal corpus callosum, which closely related to the interhemispheric integration of visual and auditory information. More importantly, we observed a negative correlation between averaged VMHC values in the postcentral gyrus and SAPS scores, and a positive correlation between the fractional anisotropy of fiber bundle connecting the bilateral precentral gyrus and Matrix Reasoning scores in schizophrenia.

CONCLUSION

Our findings provide a novel perspective of white matter functional images on understanding abnormal interhemispheric visual and auditory information transfer in schizophrenia.

Corpus callosum area and sectioning: a radioanatomical study correlated with MRI and cadaver morphometry

PURPOSE

The corpus callosum (CC) is the primary interhemispheric connection between the two cerebral hemispheres. Besides their similar morphological characters, there are differences in their measurements. This study aimed to divide the CC into groups using planes based on the anterior commissure (AC) and posterior commissure (PC) and to detect differences in CC magnetic resonance imaging (MRI) and cadaver samples between these groups.

METHODS

The study included 80 patients (40 male and 40 female patients) who underwent normal MRI in the midsagittal plane, and 38 cerebral hemispheres from 40 adult cadaver brains, with each hemisected in the midsagittal plane. The medial surface of the CC was divided vertically into three parts (the anterior, middle, and posterior zones) according to the AC and PC. Areas and parameters were measured in both the cadaveric hemispheres and patient MRI images.

RESULTS

The total CC area and CC areas between, anterior, and posterior to the AC-PC vertical lines were the same in both the MRI and cadaver samples. In addition, morphometric measurements like the CC length, AC-PC length, and CC height at the AC and PC vertical lines, and their correlations were also found to be similar between the MRI and cadaver samples.

CONCLUSION

This study proposes three areas according to AC and PC classification (anterior, middle, and posterior). This new proposed classification is suitable for stereotactic interventions and is useful for obtaining data from MRI images. However, it should be kept in mind that there may be changes and variations.

Microsurgical anatomy of the anterior cerebral artery and the arterial supply of the cingulate gyrus

PURPOSE

The cingulate gyrus is a potential surgical area to treat tumours, psychiatric diseases, intractable pain and vascular malformations. The aim of the study was to define the topographic anatomy and arterial supply of the cingulate gyrus located on the medial surface of the cerebral hemisphere.

METHODS

We studied thirty-six hemispheres, each hemisected in the midsagittal plane. The vertical thickness of the cingulate gyrus was measured at the anterior commissure (AC), posterior commissure (PC), and genu levels of the corpus callosum. The branches of the anterior and posterior cerebral arteries supplying each zone were noted separately. The arterial pathways were transformed to digital data in AutoCAD to identify the condensation and reduction areas.

RESULTS

The mean AC-PC distance was 27.17 ± 1.63 mm. The thinnest region was the genu level of the corpus callosum (10.29 mm). The superior internal parietal artery (SIPA), inferior internal parietal artery (IIPA) and pericallosal artery (PrCA) supplied all zones of the cingulate gyrus. The anterior zone received the greatest supply. The arterial condensation and reduction areas on both sides of cingulate gyrus and its x, y, and z coordinates specified.

CONCLUSIONS

The target cingulotomy (TC) area was determined for anterior cingulotomy. The properties of the TC area are that the thinnest region of the cingulate gyrus is supplied relatively less than other areas and is close to the anterior cingulotomy areas in the literature. The arterial reduction area (ARA) was found to be suitable for corpus callosotomy in terms of avoiding haemorrhage.