Pai syndrome: a further report of a case with bifid nose,lipoma, and agenesis of the corpus callosum

Introduction Pai syndrome is a rare genetic disorder mainly characterized by the association of complete median cleft of palate and upper lip, midline facial cutaneous, and mid-anterior alveolar process polyps, duplicated maxillary median frenulum, bifid nose, and midline lipoma(s) of the central nervous system, in particular, the corpus callosum. The incidence of this syndrome is much higher in males than in females. The etiology remains unknown: The syndrome may be associated with autosomal-dominant inheritance, but X-linked recessive inheritance could not be excluded. Discussion A de novo apparently balanced reciprocal traslocation, 46,X,t(X;16) has been described in a 13-year-old girl with median cleft of the upper lip, pedunculated skin masses on the nasal septum, short stature, and mental retardation. We describe a new case that presents the main clinical features associated with bifid nose, lipoma, and partial agenesis of corpus callosum.     

胼胝体动静脉畸形的显微外科治疗

报告26例胼胝体AVM（其中1例多发）的27个病灶。5个位于膝部,4个位于体部.18个位于压部。供血动脉主要来自大脑前动脉的胼周动脉;其次是大脑后动脉的脉络膜后动脉等分支。24个AVM采用显微外科手术作了全部切除。术后能正常生活者达88.5％,无死亡,并对胼胝体AVM显微外科切除手术的体会进行了讨论。     

Thickness profile generation for the corpus callosum using Laplace's equation

The corpus callosum facilitates communication between the cerebral hemispheres. Morphological abnormalities of the corpus callosum have been identified in numerous psychiatric and neurological disorders. To quantitatively analyze the thickness profile of the corpus callosum, we adapted an automatic thickness measurement method, which was originally used on magnetic resonance (MR) images of the cerebral cortex (Hutton et al. [ 2008 ]: NeuroImage 40:1701–10; Jones et al. [ 2002 ]: Hum Brain Mapp 11:12–32; Schmitt and Böhme [ 2002 ]: NeuroImage 16:1103–9; Yezzi and Prince [ 2003 ]: IEEE Trans Med Imaging 22:1332–9), to MR images of the corpus callosum. The thickness model was derived by computing a solution to Laplace's equation evaluated on callosal voxels. The streamlines from this solution form non‐overlapping, cross‐sectional contours the lengths of which are modeled as the callosal thickness. Apart from the semi‐automated segmentation and endpoint selection procedures, the method is fully automated, robust, and reproducible. We compared the Laplace method with the orthogonal projection technique previously published (Walterfang et al. [ 2009a ]: Psych Res Neuroimaging 173:77–82; Walterfang et al. [ 2008a ]: Br J Psychiatry 192:429–34; Walterfang et al. [ 2008b ]: Schizophr Res 103:1–10) on a cohort of 296 subjects, composed of 86 patients with chronic schizophrenia (CSZ), 110 individuals with first‐episode psychosis, 100 individuals at ultra‐high risk for psychosis (UHR; 27 of whom later developed psychosis, UHR‐P, and 73 who did not, UHR‐NP), and 55 control subjects (CTL). We report similar patterns of statistically significant differences in regional callosal thickness with respect to the comparisons CSZ vs. CTL, UHR vs. CTL, UHR‐P vs. UHR‐NP, and UHR vs. CTL. Hum Brain Mapp, 2011. © 2011 Wiley Periodicals, Inc.     

Alexithymia and somatization in agenesis of the corpus callosum

Deficient communication between the cerebral hemispheres is one of several prevailing neurobiological explanations for alexithymia and has been strongly supported by research on patients with commissurotomy. We examined self-reported symptoms of alexithymia in adults with agenesis of the corpus callosum (AgCC), a condition characterized by more subtle reductions in interhemispheric transfer than in commissurotomy. Sixteen adults with AgCC and full-scale intelligence quotient >80 were compared with 15 neurotypical controls group-matched for age and intelligence score. The AgCC group endorsed greater difficulty identifying and describing feelings and more vague physical symptoms than controls but similar levels of emotional experience and emotional coping. This finding of impaired emotional interpretation with intact emotional experience is consistent with findings in callosotomy patients, implicating the critical role of the corpus callosum in cognitive dimensions of emotion processing. Further study of alexithymia in AgCC using task-based measures may help clarify the nature of this relationship.     

遗传性痉挛性截瘫伴薄型胼胝体的临床特征

目的 探讨遗传性痉挛性截瘫伴薄型胼胝体（HSP-TCC）的临床特征。方法 对4例HSP-TCC患者的临床资料进行回顾性分析。结果 4例患者均于青少年起病，表现为智能低下，痉挛步态，双下肢痉挛，无力，腱反射亢进，病理征阳性，无感觉障碍，2例有共济失调及大小便障碍；1例有双上肢痉挛及肌肉萎缩，头颅MRI显示胼胝体变薄。结论 HSP-TCC的主要临床特征为青少年起病的痉挛性截瘫，智能低下，头颅MRI显示胼胝体变薄。     

Comprehension of humor in primary agenesis of the corpus callosum

Individuals with agenesis of the corpus callosum (ACC) can, in some cases, perform normally on standardized intelligence tests. Nevertheless, recent studies suggest that individuals with ACC and normal IQ scores have deficits in domains of fluid and social intelligence. Anecdotal reports from families suggest diminished appreciation of the subtleties of social interactions, and deficits in the comprehension of jokes and stories. In this research, both the cartoon and narrative joke subtests of a humor test (developed by Brownell et al. [Brownell, H., Michel, D., Powelson, J., & Gardner, H. (1983). Surprise but not coherence: sensitivity to verbal humor in right-hemisphere patients. Brain and language, 18(1), 20-27] and Bihrle et al. [Bihrle, A. M., Brownell, H. H., Powelson, J. A., & Gardner, H. (1986). Comprehension of humorous and non-humorous materials by left and right brain-damaged patients. Brain and Cognition, 5(4), 399-411]) were given to 16 adults with complete ACC (all with IQs>80) and 31 controls of similar age and IQ. Individuals with ACC performed worse than controls on the narrative joke subtest (p<.025) when VIQ was controlled. However, on the cartoon subtest the two groups were not significantly different. Covarying age, forms of IQ, narrative memory, set-switching, and literal language comprehension did not substantially alter the group difference. However, covarying comprehension of nonliteral language and proverbs eliminated the difference, suggesting a common origin for the comprehension of jokes, nonliteral language, and proverbs, most likely related to capacity for understanding second-order meanings.     

Corticosteroids impair remyelination in the corpus callosum of cuprizone-treated mice

Corticosteroids (CS) are effective in the treatment of many brain disorders, such as multiple sclerosis (MS) or traumatic brain injury. This has been scrutinised in different experimental animal models. However, neither the mechanisms, nor the site of CS action are fully understood. Short-term high-dose CS treatment improves MS symptoms and severity of clinical disability during an acute inflammatory exacerbation of disease. In the present study, we analysed the influence of CS on the expression of cellular and molecular markers of spontaneous endogenous remyelination in the toxic non-immune cuprizone animal model at early (9 days) and intermediate (21 days) remyelination, as well as steroidal effects in primary astrocytes and oligodendrocyte progenitor cultures. Dexamethasone (Dex) and methylprednisolone (MP) induced a higher expression of the differentiation markers myelin basic protein and proteolipid protein (PLP) in cultured oligodendrocyte progenitor cells (OPC). CS exposure of primary cultured astrocytes resulted in a greater expression of those genes involved in OPC proliferation [fibroblast growth factor 2 (FGF2) and platelet-derived growth factor (PDGF)-αα] and a reduced expression of the pro-maturation factor insulin-like growth factor 1. Pro-maturating effects of CS were completely blocked by FGF2 and PDGF-αα co-application in OPC cultures. MP treatment in vivo resulted in a reduced recovery of PLP-staining intensity, whereas the re-population of the demyelinated corpus callosum with adenomatous polyposis coli-expressing oligodendrocytes was not affected. The numbers of brain intrinsic inflammatory cells, microglia and astrocytes during remyelination were similar in placebo and MP-treated animals. Our findings suggest that treatment with CS might have, in addition to the well-known benefical effects on inflammatory processes, a negative influence on remyelination.     

胼胝体压部可逆性病变的MRI诊断与临床分析

目的探讨胼胝体压部(splenium of the corpus callosum,SCC)可逆性病变的MRI表现及临床特点。方法回顾性分析8例脑MRI表现为单纯胼胝体压部可逆性病变患者的临床和影像学资料。结果 8例患者的SCC可逆性病变均为继发性,原发病分别为脑内感染5例,肝豆状核变性、低血糖脑病及脑外伤各1例。8例患者均急性起病,临床表现为发热、头痛5例,急性意识障碍2例,肌张力增高2例,颈强2例,均符合原发病的临床表现。8例均行脑MRI检查,均表现为T1低或等信号,T2及FLAIR序列高信号,DWI高信号(提示细胞源性水肿),其中4例行增强扫描未见强化。8例患者均于临床症状好转或消失后复查MRI提示病灶消失。结论 SCC可逆性病变在多种疾病中均可出现,无该病变相关的特异性临床表现,MRI表现提示病灶为细胞源性水肿可能。     

A histological study of the corpus callosum in chronic schizophrenia

As a followup to a post-mortem study of the brains of schizophrenic and control subjects where the corpus callosum was found to be significantly thicker anteriorly in early onset compared to late onset schizophrenia, histological sections of 18 schizophrenic, 7 manic-depressive, and 11 medical/surgical control subjects were prepared using a stain for glia and a stain for callosal fibers. A quantitative study of the concentration of glial cells and interhemispheric callosal fibers revealed no difference between groups. A neuropathologist unaware of the tissue origin rated the histological sections for gliosis. There was significantly more severe gliosis in the callosi of the late onset schizophrenics compared to early onset schizophrenics as well as the control group. These preliminary findings suggesting callosal pathology are discussed, and the need for further studies is stressed.     

Density values of the corpus callosum in schizophrenic brains

Density values of the corpus callosum and ventricular brain ratio (VBR) were obtained by coronal computerized tomography (CT) in 16 chronic schizophrenic patients and 16 normal controls. The corpus callosum of schizophrenic brains showed no apparent density loss which could indicate a dysfunctional brain. A significant ventricular dilatation was found in the patient group compared with age-matched controls. This finding was compatible with several former observations with transverse scanning.     

Monozygotic twin cases of the agenesis of the corpus callosum with schizophrenic disorder

We report the identical monozygotic twin cases of agenesis of the corpus callosum that demonstrated schizophrenic disorder. Patients were 26-year-old twin brothers and both cases were diagnosed as having schizophrenia using DSM-III-R diagnostic criteria. On magnetic resonance imagings both cases demonstrated the total agenesis of the corpus callosum and the anterior commissure was hypertrophic. We speculated that the developmental disturbance of the corpus callosum might be related to the cause of the psychiatric disorders in the present cases.     

非酒精因素导致的原发性胼胝体变性

原发性胼胝体变性以胼胝体脱髓鞘和中心性坏死为主要病理特征,临床表现主要为精神异常、意识障碍、癫痫发作等。其病因目前尚不完全明确,常见的诱因为长期大量的酒精摄入。临床上非酒精中毒性因素导致的原发性胼胝体变性非常罕见。为提高临床医师对本病的认识,减少误诊漏诊。该文报道了1例非酒精因素导致的原发性胼胝体变性病例,该例患者以头晕为首发症状,亚急性起病,后出现发作性意识丧失、四肢僵直、二便失禁。颅脑MRI示：胼胝体肿胀,可见多发斑片状,T1WI稍低、T2WI高信号、T2-FLAIR呈稍高信号、DWI可见高信号,累及膝部、体部及压部,呈双侧对称分布。给予激素、口服维生素B1及丙戊酸钠抗癫痫治疗。治疗后病情明显好转,神志清,精神状态明显好改善,言语较前清晰,行走不稳好转。复查MRI示：双侧大脑白质和胼胝体病变范围较前缩小,异常信号较前减低。[国际神经病学神经外科学杂志, 2022, 49(5):32-35]     

Focal lesions in the splenium of the corpus callosum in patients with epilepsy

Purpose:   A focal lesion in the splenium of the corpus callosum is a rare finding in patients with epilepsy. Intoxication with antiepileptic drugs, edema after generalized seizures, or a rapid change of antiepileptic drug levels have been proposed as possible mechanisms. The aim of the present study was to analyze the relationship between this lesion and possible etiologic factors.
Patients and methods:   We analyzed the magnetic resonance imaging (MRI) scans of 1,050 patients undergoing prolonged video-EEG (electroencephalography) monitoring and identified 24 patients with a focal lesion in the splenium of the corpus callosum. Twenty-four age- and gender-matched temporal lobe epilepsy patients without such a lesion served as a control group. We evaluated the following parameters for their possible etiologic significance: epilepsy syndrome, seizure types in medical history, seizure frequency during the past year prior to admission for prolonged video-EEG monitoring, localization of interictal spikes and ictal EEG patterns in patients with focal epilepsies as documented during prolonged video-EEG-monitoring, seizure types and seizure frequency during prolonged video-EEG monitoring, past as well as current antiepileptic medication, withdrawal of antiepileptic drugs during monitoring including duration of medication withdrawal, and finally drug levels above the therapeutic range.
Results :  The parameters analyzed showed no significant difference between the group of patients with focal lesions in the splenium of the corpus callosum and the control group.
Conclusion:   We could not identify a single etiologic factor responsible for the lesion in the splenium of the corpus callosum.     

Neurons in the corpus callosum of the cat during postnatal development

The corpus callosum (CC) is a major telencephalic commissure containing mainly cortico-cortical axons and glial cells. We have identified neurons in the CC of the cat and quantified their number at different postnatal ages. An antibody against microtubule-associated protein 2 was used as a marker of neurons. Immunocytochemical double-labelling with neuron-specific enolase or gamma-aminobutyric acid antibodies in the absence of glial fibrillary acidic protein positivity confirmed the neuronal phenotype of these cells. CC neurons were also stained with anti-calbindin and anti-calretinin antibodies, typical for interneurons, and with an anti-neurofilament antibody, which in neocortex detects pyramidal neurons. Together, these findings suggest that the CC contains a mixed population of neuronal types. The quantification was corrected for double counting of adjacent sections and volume changes during CC development. Our data show that CC neurons are numerous early postnatally, and their number decreases with age. At birth, about 570 neurons are found within the CC boundaries and their number drops to about 200 in the adult. The distribution of the neurons within the CC also changes in development. Initially, many neurons are found throughout the CC, while at later ages they become restricted to the boundaries of the CC, and in the adult to the rostrum of the CC close to the septum pellucidum or to the indusium griseum. Although origin and function of transient CC neurons in development and in adulthood remain unknown, they are likely to be interstitial neurons. Some of them have well-developed and differentiated processes and resemble pyramidal cells or interneurons. An axon-guiding function during the early postnatal period can not be excluded.     

Sex differences in associations between spatial ability and corpus callosum morphology

Rotating mental representations of objects is accompanied by widespread bilateral brain activations. Thus, interhemispheric communication channels may play a relevant part when engaging in mental rotation tasks. Indeed, links between mental rotation and dimensions of the corpus callosum—the brain's main commissure system—have been reported. However, existing findings are sparse and inconsistent across studies. Here we set out to further characterize the nature of any such links, including their exact location across the corpus callosum. For this purpose, we applied an advanced image analysis approach assessing callosal thickness at 100 equidistant points in a sample of 38 healthy adults (19 men, 19 women), aged between 22 and 45 years. We detected a sex interaction, with significant structure–performance relationships in women, but not in men. Specifically, better mental rotation performance was linked to a thicker female corpus callosum within regions of the callosal splenium, posterior midbody, and anterior third. These findings may suggest sex differences in problem solving strategies where in women, more than in men, stronger interhemispheric connectivity—especially between occipitoparietal, frontal, and prefrontal regions—is associated with improved task performance. © 2018 Wiley Periodicals, Inc.     

Agenesis of the corpus callosum in Nogo receptor deficient mice

The corpus callosum (CC) is the largest fiber tract in the mammalian brain, linking the bilateral cerebral hemispheres. CC development depends on the proper balance of axon growth cone attractive and repellent cues leading axons to the midline and then directing them to the contralateral hemisphere. Imbalance of these cues results in CC agenesis or dysgenesis. Nogo receptors (NgR1, NgR2, and NgR3) are growth cone directive molecules known for inhibiting axon regeneration after injury. We report that mice lacking Nogo receptors (NgR123‐null mice) display complete CC agenesis due to axon misdirection evidenced by ectopic axons including cortical Probst bundles. Because glia and glial‐derived growth cone repellent factors (especially the diffusible factor Slit2) are required for CC development, their distribution was studied. Compared with wild‐type mice, NgR123‐null mice had a sharp increase in the glial marker glial fibrillary acidic protein (GFAP) and in Slit2 at the glial wedge and indusium griseum, midline structures required for CC formation. NgR123‐null mice displayed reduced motor coordination and hyperactivity. These data are consistent with the hypotheses that Nogo receptors are membrane‐bound growth cone repellent factors required for migration of axons across the midline at the CC, and that their absence results directly or indirectly in midline gliosis, increased Slit2, and complete CC agenesis. J. Comp. Neurol. 525:291–301, 2017. © 2016 Wiley Periodicals, Inc.