Incidence and patterns of abnormal corpus callosum in fetuses with isolated spina bifida aperta.

OBJECTIVE: To determine the incidence and characterise corpus callosum (CC) abnormalities in fetuses with spina bifida aperta (SBA) between 18 and 26 weeks of gestation. METHODS: This was a retrospective study on fetuses with isolated SBA and who were assessed for fetal surgery. Digitally stored ultrasound images of the brain were reviewed for the presence/absence of the CC, and the length and diameter of its constituent parts (rostrum, genu, body and splenium). We used regression analysis to determine the relationship between CC abnormalities and gestational age, head circumference, ventricle size, lesion level and lesion type. RESULTS: Nearly three-quarters of fetuses with isolated SBA had an abnormal CC (71.7%, 76/106). Partial agenesis was most common in the splenium (18.9%, 20/106) and the rostrum (13.2%, 14/106). The most common abnormal pattern was of a short CC with normal diameter throughout. Of note, 20.8% (22/106) had a hypoplastic genu and 28.3% (30/106) had a thick body part. Larger lateral ventricle size was associated with partial agenesis of the CC (odds ratio [OR]: 0.14, p < 0.001) and inversely associated with a shorter CC (OR: 2.60, p < 0.01). CONCLUSION: An abnormal CC is common in fetuses with isolated SBA who are referred for fetal surgery.

Corpus callosum abnormalities: neuroradiological and clinical correlations.

AIM: To study neuroradiological features in pediatric patients with corpus callosum abnormalities, using new functional subtyping for the corpus callosum, and to correlate the features with the clinical presentation. METHOD: We performed a retrospective review of 125 patients with radiologically identified abnormalities of the corpus callosum seen between 1999 and 2012. The study reviewed clinical features, genetic etiology, and chromosomal microarray (CMA) results. We used a new functional classification for callosal abnormalities based on embryological and anatomical correlations with four classes: complete agenesis, anterior agenesis (rostrum, genu, body), posterior agenesis (isthmus, splenium), and complete hypoplasia (thinning). We also studied the presence of extracallosal abnormalities. RESULTS: The new functional callosal subtyping did not reveal significant differences between the various subtypes in association with neurological outcome; however, the presence of cardiac disease was found more frequently in the group with complete agenesis. Thirty-seven per cent (46/125) had identifiable causes: of these, 48% (22/46) had a monogenic disorder, 30% (14/46) had a pathogenic chromosomal copy-number variant detected by CMA or karyotype, and 22% (10/46) had a recognizable clinical syndrome for which no confirmatory genetic test was available (namely Aicardi syndrome/septo-optic dysplasia and Goldenhar syndrome). The diagnostic yield for a significant CMA change was 19%. The presence of Probst bundles was found to be associated with a better neurodevelopmental outcome. INTERPRETATION: The functional classification system alone 'without clinical data' cannot predict the functional outcome. The presence of extracallosal brain abnormalities and an underlying genetic diagnosis predicted a worse neurodevelopmental outcome. This study highlights the importance of CMA testing and cardiac evaluation as part of a routine screen.

Comparison of cranial magnetic resonance imaging findings and clinical features in patients with corpus callosum abnormalities.

AIM: The aim of this study was to evaluate the relationship between clinical and cranial magnetic resonance imaging findings in patients with corpus callosum (CC) abnormalities. PATIENTS AND METHODS: Between September 2010 and March 2012, patients with developmental CC abnormalities were included in the study. CC abnormalities were classified as total agenesis, partial agenesis, and callosal hypoplasia. Regarding the groups, the association between radiological abnormalities and clinical findings were evaluated. RESULTS: A total of 62 patients (32 females [51.6%] and 30 males [48.4%]) with a mean age of 18.0 ± 32.1 months were enrolled in the study. Of them, 20 patients (32.3%) had total agenesis, 9 patients (14.5%) had partial agenesis, and 33 (53.2%) patients had hypoplasia of the CC. Thirty-five cases (56.7%) had abnormal physical examination, 47 cases (75.8%) had abnormal neurological examination, and 42 cases (67.7%) had psychomotor retardation. There were no significant differences between groups regarding physical examination, psychomotor retardation, seizures, or microcephaly. Seizures, psychomotor retardation, and neurological abnormalities were significantly more frequent in patients with associated other radiological abnormalities. Posterior segment of the CC was significantly thinner in patients with psychomotor retardation and the anterior part of the CC thinner in patients with abnormal physical examination. Patients with total agenesis were more prone to seizures at an early age than patients with partial agenesis or hypoplasia. CONCLUSION: The neurological prognosis of patients with CC abnormalities is poorer in patients with an associated neuroradiological abnormality. Early development of seizures may be observed in cases with total agenesis of the CC.

Agenesis of the corpus callosum: classifying functional manifestations with the ICF-CY.

PURPOSE: Agenesis of the corpus callosum (ACC) is a congenital condition in which the corpus callosum fails to develop fully. In the literature, ACC has been broadly conceptualized and inconsistently described. This article demonstrates how the universal language of the International Classification of Functioning, Disability and Health-Children and Youth can increase the specificity with which researchers and clinicians describe the variable manifestations of ACC. METHODS: The database for this article was based on a review of 83 studies on developmental and neuropsychological manifestations of congenital ACC in children and adolescents. First, the extent to which the findings on ACC could be documented using the taxonomic codes in the ICF-CY was examined. Next, the findings from each study were mapped onto the ICF-CY to summarize the distribution of clinical features reported in the literature. RESULTS: There was a high degree of correspondence between the reported findings and the taxonomic codes of the ICF-CY. The distribution of clinical features was discussed. CONCLUSIONS: This taxonomic application advances the ICF-CY as a common language for researchers and clinicians who work with children who have ACC. Implications for Rehabilitation Agenesis of the corpus callosum (ACC) is a condition that has been broadly conceptualized and inconsistently described in research and practice. The variable clinical manifestations of children with ACC can be most effectively described using the ICF-CY. The application of the ICF-CY to conditions with highly variable clinical manifestations, like ACC, positively impacts research and practice.