3D structural complexity analysis of cerebellum in Chiari malformation type I

3D Tortuosity computation as a shape descriptor and its application to brain structure analysis

In this study, we propose a novel method for quantifying tortuosity in 3D voxelized objects. As a shape characteristic, tortuosity has been widely recognized as a valuable feature in image analysis, particularly in the field of medical imaging. Our proposed method extends the two-dimensional approach of the Slope Chain Code (SCC) which creates a one-dimensional representation of curves. The utility of 3D tortuosity ( τ 3 D ) as a shape descriptor was investigated by characterizing brain structures. The results of the τ 3 D computation on the central sulcus and the main lobes revealed significant differences between Alzheimer's disease (AD) patients and control subjects, suggesting its potential as a biomarker for AD. We found a p < 0.05 for the left central sulcus and the four brain lobes.

Cognition in Chiari Malformation Type I: an Update of a Systematic Review

Chiari malformation has been classified as a group of posterior cranial fossa disorders characterized by hindbrain herniation. Chiari malformation type I (CM-I) is the most common subtype, ranging from asymptomatic patients to those with severe disorders. Research about clinical manifestations or medical treatments is still growing, but cognitive functioning has been less explored. The aim of this systematic review is to update the literature search about cognitive deficits in CM-I patients. A literature search was performed through the following electronic databases: MEDLINE, PsychINFO, Pubmed, Cochrane Library, Scopus, and Web of Science. The date last searched was February 1, 2023. The inclusion criteria were as follows: (a) include pediatric or adult participants with a CM-I diagnosis, (b) include cognitive or neuropsychological assessment with standardized tests, (c) be published in English or Spanish, and (d) be empirical studies. Articles that did not report empirical data, textbooks and conference abstracts were excluded. After the screening, twenty-eight articles were included in this systematic review. From those, twenty-one articles were focused on adult samples and seven included pediatric patients. There is a great heterogeneity in the recruited samples, followed methodology and administered neurocognitive protocols. Cognitive functioning appears to be affected in CM-I patients, at least some aspects of attention, executive functions, visuospatial abilities, episodic memory, or processing speed. However, these results require careful interpretation due to the methodological limitations of the studies. Although it is difficult to draw a clear profile of cognitive deficits related to CM-I, the literature suggests that cognitive dysfunction may be a symptom of CM-I. This suggest that clinicians should include cognitive assessment in their diagnostic procedures used for CM-I. In summary, further research is needed to determine a well-defined cognitive profile related to CM-I, favoring a multidisciplinary approach of this disorder.

Statistical Shape Analysis of Cerebellum in Patients With Chiari Malformation I

The surgical procedure is viewed as a typical treatment choice for patients with Chiari malformation (CM). Decompression is the preferred method for surgery, but it is not always possible to understand whether decompression has been successful especially in an early period. The present study focuses on investigating the shape differences in the cerebellums of Chiari patients compared with healthy controls, and to assess the clinical application of this situation whether if present. The MRI scans were reviewed retrospectively. Cerebellar data were obtained from the digital images and 9 anthropometric landmarks were marked on each image. Shape difference was assessed by performing Generalized Procrustes analysis. The cerebellar shape deformation from control to the patient was evaluated performing the Thin Plate Spline approach. There is a statistically significant cerebellar shape difference between groups. Highest deformation was determined at the cerebellar tonsillar inferior area, posterior of the uvula, and anterior of inferior medullary velum. The present study demonstrated cerebellar shape differences in CM I patients using a landmark-based geometric morphometric approach, considering the topographic distribution of cerebellum for the first time.

Cognitive Functioning in Chiari Malformation Type I Without Posterior Fossa Surgery

Chiari Malformation type I (CM-I) is a neurological disorder characterized by a displacement of the cerebellar tonsils through the foramen magnum into the spinal canal. Most research has focused on physical symptomatology but few studies include neuropsychological examinations. Moreover, although current research highlights the involvement of the cerebellum on higher cognitive functions, little is known about cognitive consequences associated with CM-I. The aim of this study is to analyze cognitive functioning between 39 CM-I patients and 39 healthy controls, matched by gender, age and years of education. Participants have been examined on a large battery of neuropsychological tests, including executive functioning, verbal fluency, spatial cognition, language, verbal memory, processing speed, facial recognition and theory of mind. Results show a poorer performance of the clinical group compared to the control group, even after controlling the effect of physical pain and anxious-depressive symptomatology. The findings suggest the presence of a generalized cognitive deficit associated with CM-I, which makes it necessary to focus attention not only on physical consequences, but also on cognitive ones.

Developments in the treatment of Chiari type 1 malformations over the past decade

Background

Chiari malformations type 1 (CM-1), a developmental anomaly of the posterior fossa, usually presents in adolescence or early adulthood. There are few studies on the national incidence of CM-1, taking into account outcomes based on concurrent diagnoses. To quantify trends in treatment and associated diagnoses, as retrospective review of the Kid's Inpatient Database (KID) from 2003-2012 was conducted.

Methods

Patients aged 0-20 with primary diagnosis of CM-1 in the KID database were identified. Demographics and concurrent diagnoses were analyzed using chi-squared and t-tests for categorical and numerical variables, respectively. Trends in diagnosis, treatments, and outcomes were analyzed using analysis of variance (ANOVA).

Results

Five thousand four hundred and thirty-eight patients were identified in the KID database with a primary diagnosis of CM-1 (10.5 years, 55% female). CM-1 primary diagnoses have increased over time (45 to 96 per 100,000). CM-1 patients had the following concurrent diagnoses: 23.8% syringomyelia/syringobulbia, 11.5% scoliosis, 5.9% hydrocephalus, 2.2% tethered cord syndrome. Eighty-three point four percent of CM-1 patients underwent surgical treatment, and rate of surgical treatment for CM-1 increased from 2003-2012 (66% to 72%, P<0.001) though complication rate decreased (7% to 3%, P<0.001) and mortality rates remained constant. Seventy percent of surgeries involved decompression-only, which increased neurologic complications compared to fusions (P=0.039). Cranial decompressions decreased from 2003-2012 (42.2-30.5%) while spinal decompressions increased (73.1-77.4%). Fusion rates have increased over time (0.45% to 1.8%) and are associated with higher complications than decompression-only (11.9% vs. 4.7%). Seven point four percent of patients experienced at least one peri-operative complication (nervous system, dysphagia, respiratory most common). Patients with concurrent hydrocephalus had increased; nervous system, respiratory and urinary complications (P<0.006) and syringomyelia increased the rate of respiratory complications (P=0.037).

Conclusions

CM-1 diagnoses have increased in the last decade. Despite the decrease in overall complication rates, fusions are becoming more common and are associated with higher peri-operative complication rates. Commonly associated diagnoses including syringomyelia and hydrocephalus, can dramatically increase complication rates.