Long-term outcome of operated Chiari I patients between 2005 and 2020 in Eastern Finland.

PURPOSE: The purpose of our study was to examine the long-term outcomes of operated Chiari malformation type 1 (CM1) patients and evaluate whether different duraplasty techniques affected outcome after surgery in Kuopio University Hospital catchment area. METHODS: In this retrospective study, a total of 93 patients were diagnosed with CM1 and underwent posterior fossa decompression surgery with or without duraplasty between 2005 and 2020. All patients' medical records were examined for baseline characteristics, surgical details, and long-term follow-up data after operation. RESULTS: The mean age of CM1 patients was 25.9 years (SD 19.2 years), with female preponderance 69/93 (73.4%). The mean clinical follow-up time was 26.5 months (SD 33.5 months). The most common presenting symptoms were headache, symptoms of extremities, and paresthesia. Posterior fossa decompression with duraplasty was performed in 87 (93.5%) patients and bony decompression in 6 (6.5%) patients. After surgery, preoperative symptoms alleviated in 84.9% (79/93) and the postoperative syringomyelia regression rate was 89.2% (33/37) of all patients. The postoperative complication rate was 34.4% (32/93), with aseptic meningitis being the most common, 25.8% (24/93). Revision surgery was required in 14% (13/93) of patients. No significant correlation between postoperative outcome and extent of dural decompression, or type of duraplasty performed was found. CONCLUSION: This is the largest reported series of surgically treated CM1 patients in Finland. Posterior fossa decompression is an effective procedure for CM1 symptomology. Duraplasty technique had no significant difference in complication rate or long-term outcomes.

Influence of affective disorders on outcomes after suboccipital decompression for adult Chiari I malformation.

INTRODUCTION: Affective disorders (AD) have been shown to influence patient outcomes and healthcare resource utilization across several pathologies, though this relationship has not been described in patients with Chiari I malformations (CM-I). The aim of this study was to determine the impact of comorbid AD on postoperative events and healthcare resource utilization in adults following suboccipital decompression for CM-I. METHODS: A retrospective study was performed using the 2016-2019 National Inpatient Sample database. Adults who underwent suboccipital decompression for CM-I were identified using ICD-10-CM codes. Patients were stratified into two cohorts, those with AD and those without (No AD). Patient demographics, comorbidities, operative characteristics, perioperative adverse events (AEs), and healthcare resource utilization were assessed. Multivariate logistic regression analyses were used to identify independent predictors of prolonged length of stay (LOS), exorbitant admission costs, and non-routine discharge (NRD). RESULTS: A total of 3985 patients were identified, of which 2780 (69.8%) were in the No AD cohort and 1205 (30.2%) were in the AD cohort. Patient demographics were similar, except for a greater proportion of Female patients than the No AD cohort (p = 0.004). Prevalence of some comorbidities varied between cohorts, including obesity (p = 0.030), ADHD (p < 0.001), GERD (p < 0.001), smoking (p < 0.001), and chronic pulmonary disease (p < 0.001). The AD cohort had a greater proportion of patients with 1-2 (p < 0.001) or ≥ 3 comorbidities (p < 0.001) compared to the No AD cohort. A greater proportion of patients in the AD cohort presented with headache compared to the No AD cohort (p = 0.003). Incidence of syringomyelia was greater in the No AD cohort (p = 0.002). A greater proportion of patients in the No AD cohort underwent duraplasty only (without cervical laminectomy) compared to the AD cohort (p = 0.021). Healthcare resource utilization was similar between cohorts, with no significant differences in mean LOS (No AD: 3.78 ± 3.51 days vs. 3.68 ± 2.71 days, p = 0.659), NRD (No AD: 3.8% vs. AD: 5.4%, p = 0.260), or mean admission costs (No AD: $20,254 ± 14,023 vs. AD: $29,897 ± 22,586, p = 0.284). On multivariate analysis, AD was not independently associated with extended LOS [OR (95%CI): 1.09 (0.72-1.65), p = 0.669], increased hospital costs [OR (95%CI): 0.98 (0.63-1.52), p = 0.930], or NRD [OR (95%CI): 1.39 (0.65-2.96), p = 0.302]. CONCLUSION: Our study suggests that the presence of an AD may not have as much of an impact on postoperative events and healthcare resource utilization in adult patients undergoing Chiari decompression. Additional studies may be warranted to identify other potential implications that AD may have in other aspects of healthcare in this patient population.

The prevalence of Chiari malformation among children with persistent dysphagia.

BACKGROUND: Brain imaging has been utilized as a diagnostic tool in the workup of persistent pediatric dysphagia, yet the indications for imaging and the prevalence of Chiari malformation (CM) have not been established. OBJECTIVE: to evaluate the prevalence of CM anomalies in children who underwent brain magnetic resonance imaging (MRI) for pharyngeal dysphagia and to review the clinical findings in the CM group compared to the non-CM group. METHODS: A retrospective cohort study of children who underwent MRI as part of the workup for the diagnosis of dysphagia in a tertiary care children's hospital between 2010 and 2021. RESULTS: 150 patients were included. The mean age at diagnosis of dysphagia was 1 ± 3.4 years, and the mean age at MRI was 3.5 ± 4.2 years. Common comorbidities in our cohort included prematurity (n = 70, 46.7 %), gastroesophageal reflux (n = 65, 43.3 %), neuromuscular/seizure disorder (n = 53,35.3 %), and underlying syndrome (n = 16, 10.7 %). Abnormal brain findings were seen in 32 (21.3 %) patients, of whom 5 (3.3 %) were diagnosed with CM-I and 4 (2.7 %) patients with tonsillar ectopia. Clinical characteristics and dysphagia severity were similar between patients with CM-I/tonsillar ectopia and patients without tonsillar herniation. CONCLUSIONS: Brain MRI should be pursued as part of the work-up for persistent dysphagia in pediatric patients given the relatively higher prevalence of CM-I. Multi-institutional studies are required to establish the criteria and timing of brain imaging in patients with dysphagia.

Prevalence of Chiari malformation type 1 is increased in pseudohypoparathyroidism type 1A and associated with aberrant bone development.

BACKGROUND: Albright hereditary osteodystrophy (AHO) is caused by heterozygous inactivating mutations in GNAS. Patients with maternally-inherited mutations develop pseudohypoparathyroidism type 1A (PHP1A) with multi-hormone resistance and aberrant craniofacial and skeletal development among other abnormalities. Chiari malformation type 1 (CM1), a condition in which brain tissue extends into the spinal canal when the skull is too small, has been reported in isolated cases of PHP1A. It has been hypothesized to be associated with growth hormone (GH) deficiency. Given the adverse clinical sequelae that can occur if CM1 goes unrecognized, we investigated the previously undetermined prevalence of CM1, as well as any potential correlations with GH status, given the known increased prevalence of GH deficiency in PHP1A. We also investigated these metrics for low lying cerebellar tonsils (LLCT), defined as tonsillar descent less than 5 mm below the foramen magnum. In addition, we investigated possible correlations of CM1/LLCT with advanced hand/wrist bone ages and craniofacial abnormalities known to occur in PHP1A to determine whether premature chondrocyte differentiation and/or aberrant craniofacial development could be potential etiologies of CM1/LLCT through both human studies and investigations of our AHO mouse model. METHODS: We examined patients with PHP1A in our clinic and noticed CM1 more frequently than expected. Therefore, we set out to determine the true prevalence of CM1 and LLCT in a cohort of 54 mutation-confirmed PHP1A participants who had clinically-indicated brain imaging. We examined potential correlations with GH status, clinical features, biological sex, genotype, and hand/wrist bone age determinations. In addition, we investigated the craniofacial development in our mouse model of AHO (Gnas E1+/-m) by histologic analyses, dynamic histomorphometry, and micro-computerized tomographic imaging (MCT) in order to determine potential etiologies of CM1/LLCT in PHP1A. RESULTS: In our cohort of PHP1A, the prevalence of CM1 is 10.8%, which is at least 10-fold higher than in the general population. If LLCT is included, the prevalence increases to 21.7%. We found no correlation with GH status, biological sex, genotype, or hand/wrist bone age. Through investigations of our Gnas E1+/-m mice, the correlate to PHP1A, we identified a smaller cranial vault and increased cranial dome angle with evidence of hyperostosis due to increased osteogenesis. We also demonstrated that there was premature closure of the spheno-occipital synchondrosis (SOS), a cartilaginous structure essential to the development of the cranial base. These findings lead to craniofacial abnormalities and could contribute to CM1 and LLCT development in PHP1A. CONCLUSION: The prevalence of CM1 is at least 10-fold higher in PHP1A compared to the general population and 20-fold higher when including LLCT. This is independent of the GH deficiency that is found in approximately two-thirds of patients with PHP1A. In light of potential serious consequences of CM1, clinicians should have a low threshold for brain imaging. Investigations of our AHO mouse model revealed aberrant cranial formation including a smaller cranium, increased cranial dome angle, hyperostosis, and premature SOS closure rates, providing a potential etiology for the increased prevalence of CM1 and LLCT in PHP1A.

Prevalence and treatment of typical and atypical headaches in patients with Chiari I malformation: A meta-analysis and literature review.

OBJECTIVE: A meta-analysis was conducted to analyze the incidence of typical and atypical headaches and outcomes following various treatments in patients with Chiari I malformation. BACKGROUND: Headache is the most common symptom of Chiari malformation, which can be divided into typical and atypical subgroups to facilitate management. Much controversy surrounds the etiology, prevalence and optimal therapeutic approach for both types of headaches. METHOD: We identified relevant studies published before 30 July 2022, with an electronic search of numerous literature databases. The results of this study were reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. RESULT: A total of 1913 Chiari malformation type I CIM patients were identified, 78% of whom presented with headache, within this group cephalgia was typical in 48% and atypical in 29% of patients, and migraine was the most common type of atypical headache. The ratio of typical/atypical headaches with international classification of headache disorders diagnosis was 1.53, and without international classification of headache disorders diagnosis was 1.56, respectively. The pooled improvement rates of typical headaches following conservative treatment, extradural decompression and intradural decompression were 69%, 88%, and 92%, respectively. The corresponding improvement rates for atypical headaches were 70%, 57.47%, and 69%, respectively. The complication rate in extradural decompression group was significantly lower than in intradural decompression group (RR, 0.31; 95% CI: 0.06-1.59, I2 = 50%, P = 0.14). Low reoperation rates were observed for refractory headaches in extradural decompression and intradural decompression groups (1%). CONCLUSION: The International Classification of Headache Disorders can assist in screening atypical headaches. extradural decompression is preferred for typical headaches, while conservative therapy is optimal for atypical headaches. A definite correlation exists between atypical headaches and Chiari Malformation Type I patients with higher prevalence than in the general population. Importantly, decompression is effective in relieving headaches in this particular patient population.

Elucidating the Genetic Basis of Chiari I Malformation.

Several studies have been performed to elucidate the genetic basis of Chiari I malformation (CM1). The heritability of CM1 is clear from twin studies, familial clustering, and the prevalence of CM1 among certain classes of Mendelian disorders, namely connective tissue disorders, brain overgrowth disorders, disorders of CSF homeostasis, certain tumors, disorders of skull development and vascular conditions. A comprehensive understanding of the causes of CM1 will require large cohorts of patients for genetic studies and in-depth phenotyping of cases to better understand the biological mechanisms underlying disease.

Epidemiology of Chiari I Malformation and Syringomyelia.

Chiari I malformation is a common condition seen by adult and pediatric neurosurgeons. With increased utilization of MRI over time, incidental findings of Chiari I malformation are occurring more frequently. The prevalence of symptomatic Chiari I malformation is much smaller than that of asymptomatic Chiari I malformation. The prevalence of Chiari I malformation-associated syringomyelia is likely overestimated in the literature. The epidemiology of Chiari I malformation and associated syringomyelia differs based on age, sex, ethnicity, race, and socioeconomic status. The natural history of Chiari I malformation and associated syringomyelia appears to be quite benign as few patients who are managed nonsurgically later require surgical intervention.

Impact of sleep-disordered breathing on the management of children with Chiari malformation type I.

OBJECTIVES: Children with Chiari malformation type I (CM-I) have an increased risk of sleep apnea. The aim of the study was to describe the management of CM-I patients in relation to symptoms, magnetic resonance imaging (MRI) findings and sleep apnea syndrome (SAS). METHODS: We performed a retrospective analysis of clinical charts of all 57 CM-I patients seen between September 2013 and April 2017. RESULTS: A total of 45 patients had isolated CM-I or associated co-morbidity (CM-Iia), 5 had craniosynostosis (CM-Ics), and 7 a polymalformative syndrome (CM-Ipm). The prevalence of SAS, defined as an apnea-hypopnea index >1 event/h, was high in CM-I ranging from 50% to 80% according to the CM-I group. The prevalence of central sleep apnea (CSA) was low, with 5 (9%) patients having CSA and only 3 patients with CM-Iia having isolated CSA. A total of 17 patients (30%) had foramen magnum decompression (FMD). Neither positive symptoms of CM-I nor MRI findings alone, nor both combined were good indicators for FMD. No correlation was observed between the cerebellar tonsil descent and SAS in CM-I. But all 5 patients with CSA had a FMD. The combination of MRI findings and/or symptoms of CM-I together with moderate-to-severe SAS best discriminated patients who needed a FMD. CONCLUSION: Our findings highlight the importance of a combined evaluation of symptoms, MRI and polygraphy results in the management of CM-I patients.

Sleep-disordered breathing in patients with Chiari malformation type II: a case-control study and review of the literature.

STUDY OBJECTIVES: The main aim was to evaluate the prevalence of sleep-disordered breathing (SDB) in patients with Chiari II malformation (CM-II). The secondary objectives were to evaluate the association between SDB, morphological abnormalities, and neurological symptoms and to review the literature on patients with SDB and CM-II. METHODS: The study has a cross-sectional, case-control design. Patients with CM-II (patients) were compared to control patients referred for clinical polysomnography in the Sleep Medicine Unit, matched for age and sex. All patients underwent brain and spinal cord magnetic resonance imaging, and polysomnography was conducted for all participants. A review of the literature about SDB in patients with CM-II was performed. RESULTS: Forty patients were included (20 patients vs 20 control patients). SDB was identified in 45% of patients, a significantly higher prevalence compared to control patients. Three patients presented with purely obstructive SDB, 3 patients with purely central SDB, and 3 patients with both obstructive and central SDB. Compared with control patients, patients with CM-II showed a higher oxygen desaturation index (median: CM-II, 3.7; interquartile range, 1.6-19.5; control patients: 1.1; interquartile range, 0.3-3.2) and obstructive apnea-hypopnea index (median: CM-II, 1.5; interquartile range, 0.5-5.1; control patients, 0.1; interquartile range, 0.0-0.7). A logistic regression showed that the risk of developing SDB in patients affected by CM-II was 14.7 times higher than in the control population. CONCLUSIONS: Our study and literature review showed a high prevalence of SDB in patients with CM-II. These patients are often asymptomatic at diagnosis, suggesting that PSG should be routinely provided in this population. CITATION: Lazzareschi I, Curatola A, Massimi L, et al. Sleep-disordered breathing in patients with Chiari malformation type II: a case-control study and review of the literature. J Clin Sleep Med. 2022;18(9):2143-2154.

Management of Sleep Apnea in Children with Chiari I Malformation: A Retrospective Study.

INTRODUCTION: The literature indicates that decompression of Chiari I malformations (CM-1) may resolve symptoms of sleep apnea. This study aims to identify the incidence of obstructive sleep apnea (OSA), central sleep apnea (CSA), and mixed sleep apnea in a cohort of pediatric CM-1 patients treated at our institution. We also assessed apnea-hypopnea index and symptomatology before and after surgery to investigate if Chiari decompression is a viable treatment for sleep apnea in CM-1 patients. Improvement relative to ENT surgical intervention was also considered. METHODS: We identified 75 patients who underwent polysomnography (PSG) from our database of 465 CM-1 patients. Sleep apnea diagnosis was based on the sleep physician's overall interpretation of the PSG. Symptomatology pre- and post-surgery was analyzed. RESULTS: Of the 75 CM-1 patients that underwent PSG, 23 were diagnosed with sleep apnea. Sixteen had OSA, 6 had CSA, and 1 had mixed apnea. Twelve OSA patients received ENT intervention. Eight improved and 2 further improved after Chiari decompression. Of the 4 patients that did not improve, one of those later improved following Chiari decompression. Of the 6 CSA patients, 2 underwent Chiari decompression, but only one improved. The mixed apnea patient underwent several ENT interventions that did not relieve symptoms but improved following Chiari decompression. DISCUSSION/CONCLUSIONS: Based on our results, sleep apnea in CM-1 patients may be obstructive, central, or mixed and is likely multifactorial. A multidisciplinary approach to the management of these patients is important, including neurosurgery, otolaryngology, and sleep medicine. Future prospective studies will lend further insight into this condition and its management.

Craniocervical Stabilization After Failed Chiari Decompression: A Case Series of a Population with High Prevalence of Ehlers-Danlos Syndrome.

BACKGROUND: In the treatment of Chiari malformation type I (CM-I), posterior fossa decompression is achieved via suboccipital craniectomy (SOC); however, some patients continue to experience symptoms after treatment, which may be due to craniocervical instability (CCI). The purposes of this study were to analyze data from patients who required an occipitocervical fusion (OCF) for the management of CCI after having previously undergone SOC for CM-I to determine if OCF is a safe and effective option and to determine any identifiable risk factors for CCI in these patients. METHODS: A retrospective review was done on all patients who underwent an OCF performed by the senior author between November 2013 and June 2020 after having previously undergone SOC for CM-I. Demographic, radiographic, perioperative, and outcome data were collected and clivoaxial angles (CXAs) were measured pre- and postoperatively. RESULTS: Fifteen patients were identified who developed symptomatic CCI after previously undergoing a suboccipital craniectomy for the treatment of CM-I. All 15 patients were treated by OCF with good outcome. Of these, 12 patients had a known diagnosis of Ehlers-Danlos syndrome (EDS). Overall, the CXAs of these patients were found to be corrected to a more anatomical alignment. CONCLUSIONS: Symptomatic CCI should be recognized as a delayed postoperative complication in the surgical treatment of CM-I, with an underlying connective tissue hypermobility disorder such as EDS serving as a potential risk factor its development. CCI can be managed with OCF as a safe and effective treatment option for this patient population.

New Association between Idiopathic Scoliosis and Luckenschadel Skull (Lacunar Skull).

OBJECTIVE: Luckenschadel skull is a skull that is radiologically characterized by lacunae in the cranial vault. To date, although the association between neurological abnormalities and scoliosis is well recognized, no relationship between idiopathic scoliosis and a lacunar skull has been defined. We explored the incidence and time courses of lacunar skulls in patients with idiopathic scoliosis. MATERIALS AND METHODS: Spinal X-rays of 3,170 children aged 6-16 years with idiopathic scoliosis evaluated from October 2010 to August 2020 were examined for the presence of an irregular inner calvarial table indicative of a Luckenschadel skull. A total of 1,760 (55.5%) of the 3,170 images included the skull. We also explored the frequency of intraspinal abnormalities in children with lacunar skull images who underwent spinal magnetic resonance imaging. RESULTS: The study population consisted of 1,760 children, 1,203 girls (68.4%) and 557 (31.6%) boys. A total of 268 (15.2%) clearly evidenced lacunar skulls in their radiographs; 186 (69.4%) girls (11.3 ± 4.3 years) and 82 (30.6%) boys (12.6 ± 3.3 years). Two of the 56 patients (3.6%) who underwent spinal MRI had intraspinal abnormalities (isolated Chiari malformation-I). No additional neurological problems were detected in children with lacunar skulls. CONCLUSION: We conclude that the lacunar skull is very common in children with idiopathic scoliosis who lack any other neurological pathology. The lacunar skull does not disappear even in adolescence. Although previous publications have stated that lacunar skull disappears over time in radiographic images, we observed that it became more noticeable over time in children with scoliosis.

Migraine in Chiari 1 Malformation: a cross-sectional, single centre study.

In Chiari 1 Malformation (CM1) the most frequent symptom is exertional headache, but other headache types have been reported, such as migraine. This cross-sectional study is aimed to examine the prevalence of migraine in a group of CM1 headache patients and to compare clinical-demographic characteristics between migraine and non-migraine patients. 427 adults were enrolled at the multidisciplinary Chiari Center in Torino. 230 headache patients were classified, based on radiological criteria. Frequencies (absolute/percentage values) were calculated in the whole sample for: migraine presence (with and without aura), gender, age, radiologic phenotypes and headache clinical characteristics. The association between CM1 diagnosis and headache characteristics (independent variables) and migraine diagnosis (dependent variable) was estimated by logistic regression models. Seventy-eight patients (67 females) out of 230 presenting headache had a migraine (34%), 44/78 (56%) with aura; in 58/78 (74%) migraine was comorbid with secondary headache attributable to CM1. Migraine prevalence in patients with isolated CM1 (52/120, 43.3%) was higher (p = 0.0016) than in all the other patients (26/110, 23.6%). Although migraine was prevalent in females (86%; 6:1 female:male ratio), age classes and gender were not risk factors for migraine at multivariate analysis, while migraine was associated with isolated CM1 phenotype (OR = 2.6). This study shows a high prevalence of migraine in CM1 patients and a significant association between migraine and isolated CM1. In patients with radiological evidence of CM1, particularly in the absence of neurological signs, a careful headache clinical characterization, according to the International Headache Society criteria, may be advised.

The management of Chiari malformation type 1 and syringomyelia in children: a review of the literature.

In anticipation of the "Chiari and Syringomyelia Consensus Conference" held in Milan in 2019, we performed a systematic literature review on the management of Chiari malformation type 1 (CM1) and syringomyelia (Syr) in children.We aimed to summarize the available evidence and identify areas where consensus has not been reached and further research is needed.In accordance with PRISMA guidelines, we formulated seven questions in Patients-Interventions-Comparators-Outcomes (PICO) format. Six PICOs concerned CM1 children with/without additional structural anomalies (Syr, craniosynostosis, hydrocephalus, tethered cord, and cranio-vertebral junction anomalies), and one PICO Syr without CM1. We searched Medline, Embase, Cochrane, and NICE databases from January 1, 1999, to May 29, 2019. Cohort studies, controlled and randomized clinical trials (CCTs, RCTs), and systematic reviews were included, all pertinent only to patients ≤ 18 years of age.For CM1, 3787 records were found, 460 full texts were assessed and 49 studies (46 cohort studies, one RCT, and two systematic reviews) were finally included. For Syr, 376 records were found, 59 full texts were assessed, and five studies (one RCT and four cohort studies) were included. Data on each PICO were synthetized narratively due to heterogeneity in the inclusion criteria, outcome measures, and length of follow-up of the included studies.Despite decades of experience on CM1 and Syr management in children, the available evidence remains limited. Specifically, there is an urgent need for collaborative initiatives focusing on the adoption of shared inclusion criteria and outcome measures, as well as rigorous prospective designs, particularly RCTs.

Longitudinal scoliosis behavior in Chiari malformation with and without syringomyelia.

OBJECTIVE: The objective of this study was to understand the natural history of scoliosis in patients with Chiari malformation type I (CM-I) with and without syringomyelia. METHODS: A retrospective review of data was conducted. Patients with CM-I were identified from a cohort of 14,118 individuals age 18 years or younger who had undergone MRI over an 11-year period at the University of Michigan. Patients eligible for study inclusion had a coronal curve ≥ 10° on radiography, associated CM-I with or without syringomyelia, and at least 1 year of clinical follow-up prior to any surgery. Curve magnitude at initial diagnosis, prior to posterior fossa decompression (PFD; if applicable), and at the last follow-up (prior to any surgical correction of scoliosis) was recorded, and clinical and radiographic characteristics were noted. The change in curve magnitude by 10° was defined as curve progression (increase by 10°) or regression (decrease by 10°). RESULTS: Forty-three patients met the study inclusion criteria and were analyzed. About one-third (35%) of the patients presented with symptoms attributed to their CM-I. The mean degree of scoliosis at presentation was 32.6° ± 17.7°. Twenty-one patients (49%) had an associated syrinx. The mean tonsil position below the level of the foramen magnum was 9.8 ± 5.8 mm. Patients with a syrinx were more likely to have a curve > 20° (86% vs 41%, p = 0.002). Curve magnitude remained stable (≤ ±10°) in 77% of patients (33/43), progressed in 16% (7/43), and regressed in 7% (3/43). Mean age was higher (14.8 ± 0.59 years) among patients with regressed curves (p = 0.026). All regressed curves initially measured ≤ 20° (mean 14° ± 5.3°), and none of the patients with regressed curves had a syrinx. The change in curve magnitude was statistically similar in patients with (7.32° ± 17.7°) and without (5.32° ± 15.8°) a syrinx (p = 0.67). After a mean follow-up of 3.13 ± 2.04 years prior to surgery, 27 patients (63%) ultimately underwent posterior fossa or scoliosis correction surgery. For those who eventually underwent PFD only, the rate of change in curve magnitude prior to surgery was 0.054° ± 0.79°. The rate of change in curve magnitude was statistically similar before (0.054° ± 0.79°) and after (0.042° ± 0.33°) surgery (p = 0.45) for patients who underwent PFD surgery only. CONCLUSIONS: The natural history of scoliosis in the presence of CM-I is variable, though most curves remained stable. All curves that regressed were ≤ 20° at initial diagnosis, and most patients in such cases were older at scoliosis diagnosis. Patients who underwent no surgery or PFD only had similar profiles for the change in curve magnitude, which remained relatively stable overall, as compared to patients who underwent PFD and subsequent fusion, who demonstrated curve progression. Among the patients with a syrinx, no curves regressed, most remained stable, and some progressed. Understanding this variability is a first step toward building a prediction model for outcomes for these patients.

Long-term outcomes of surgical management in subtypes of Chiari malformation.

Objective: Chiari malformations (CMs) are a heterogeneous group of disorders defined by anatomic anomalies of the cerebellum, brainstem, and craniovertebral junction (CVJ). The aims of this study are to establish the demographic and clinical features, incidence, surgical procedures, and outcomes in large series of old and new subtypes of CMs.Material and Methods: All patients were evaluated and operated on for CM-0, 1, and 1.5 between 1985 and 2016. The patients were grouped into various subtypes. Demographic data, additional diseases, clinical features, surgical procedures, complications and outcomes were recorded.Results: 191 patients who underwent various surgical procedures were evaluated. Their mean age was 37.21 ± 9.89. We detected 15 cases of CM-0 (7.8%), 121 cases of CM-1 (63.4%), 55 cases of CM-1.5 (28.8%). In total there were 191 cases, and 220 surgical procedures were performed. 29 (13.2%) of all surgical procedure was reoperations and secondary operations. SM Cyst is found to be decreased in 72 (76.5%) patients, unchanged in 14 (14.8%) and increased in 8(8.5%) of 94 patients radiologically. Clinical outcomes are better for 131 (65.8%), same for 31 (16.2%) and worse for 9 (15%).Conclusion: This study with 172 patients is a large series that includes CM-0, 1, and 1.5 subtypes. CM-1.5 also differs for symptom presentation and durations from CM-1. There are more neurological abnormalities in patients with SM. CVD alone are an effective, useful and safe surgical procedure for CM-0, CM-1 and CM-1.5. Surgical procedure, SM existence, and symptom duration have powerful effects on outcomes.

Statistical Shape Analyses of the Brainstem in Chiari Patients.

AIM: To ascertain whether the brain stem?s shape differs in patients with syrinx and without syrinx in cases with Chiari malformation Type I (CM-1), relative to healthy controls. MATERIAL AND METHODS: Data on marked brainstem regions were obtained from 2D digital image files. Generalized Procrustes analysis was used to evaluate shape differences among patients with syrinx, patients without syrinx, and healthy controls. Shape deformations among groups were examined by Thin Plate Spline (TPS) analysis. RESULTS: According to the brain stem shape, there were differences between patients with syrinx and controls, and between patients without syrinx and controls. High-level deformations were also observed among the groups. CONCLUSION: In the present study, the presence of shape deformations in Chiari patients? brainstem was demonstrated. This is the first study using a landmark-based geometrical morphometric method to demonstrate the shape difference in Chiari patients? brainstem.

The executive functions, intellectual capacity, and psychiatric disorders in adolescents with Chiari malformation type 1.

PURPOSE: In the last two decades, the non-motor functions of the cerebellum have become the centre of attention for researchers. Anecdotal observations of cognitive and psychiatric manifestations of cerebellar lesions have increased this interest. We aimed to investigate the executive function (EF), intellectual capacity, and comorbid psychiatric disorders in adolescents with Chiari malformation type 1 (CM1), which is a pathological manifestation of posterior cranial fossa structures include the cerebellum. METHODS: The Chiari group consisted of ten adolescents aged 12-18 years old, and the control group consisted of 13 healthy adolescents with similar age and sex with patients. Stroop test (ST), trail making test (TMT), and Behaviour Rating Inventory of Executive Function-Parent form (BRIEF) were used to evaluate EF; Kent EGY and Porteus Maze Test was used to measuring the intelligence quotient (IQ), and a semi-structured interview was used to determine the psychiatric disorders. RESULTS: EF test scores were found comparable between the two groups. IQ scores of the Chiari group were found in the normal range, but significantly lower than controls. No significant difference was revealed in terms of comorbid psychiatric disorders between the two groups. CONCLUSION: In this study, we did not observe an impairing effect of CM1 on EF and intelligence. Also, we found that CM1 did not cause more psychiatric disorders compared to controls. Further studies need to support our findings in adolescents diagnosed with CM1.

Are craniocervical angulations or syrinx risk factors for the initiation and progression of scoliosis in Chiari malformation type I?

The pathophysiology behind the instigation and progression of scoliosis in Chiari malformation type I (CMI) patients has not been elucidated yet. This study aims to explore the initiating and progressive factors for scoliosis secondary to CMI. Pediatric patients with CMI were retrospectively reviewed for radiological characteristics of tonsillar herniation, craniocervical anomaly, syrinx morphology, and scoliosis. Subgroup analyses of the presence of syrinx, scoliosis, and curve progression were also performed. A total of 437 CMI patients were included in the study; 62% of the subjects had syrinx, and 25% had scoliosis. In the subgroup analysis of 272 CMI patients with syrinx, 78 of them (29%) had scoliosis, and multiple logistic regression analysis showed that tonsillar herniation ≥ 10 mm (OR 2.13; P = 0.033) and a clivus canal angle ≤ 130° (OR 1.98; P = 0.025) were independent risk factors for scoliosis. In the subgroup analysis of 165 CMI patients without syrinx, 31 of them (19%) had scoliosis, and multiple logistic regression analysis showed that a clivus canal angle ≤ 130° (OR 3.02; P = 0.029) was an independent risk factor for scoliosis. In the subgroup analysis of curve progression for 97 CMI patients with scoliosis, multiple logistic regression analysis showed that anomalies of the craniocervical junction and syrinx were not risk factors for curve progression. Many complex factors including craniocervical angulation, tonsillar herniation, and syrinx might participate in the instigation of scoliosis for CMI patients, and the relationship between craniocervical angulation and scoliosis deserves further study.

Clinicoradiographic data and management of children with Chiari malformation type 1 and 1.5: an Italian case series.

INTRODUCTION: The widespread use of imaging has increased Chiari malformation (CM) diagnosis. CM shows clinical heterogeneity that makes management controversial. We aimed to evaluate the occurrence and clinical and radiographic presentation of children with CM-1 and CM-1.5, reporting possible differences according to age and management. METHODS: We retrospectively reviewed 46 children diagnosed with CM-1 or CM-1.5, between 2006 and 2019 at our institute. We evaluated for each subject: reason for hospital admission, clinical presentation, age at diagnosis, extent of cerebellar tonsillar herniation (CTH) and type of treatment when carried out. Affected children were assigned to three age groups. In some patients, a clinical follow-up was carried out. RESULTS: Mean age at diagnosis was 7.61 years. Mean CTH was 8.72 mm. Syringomyelia was found in 10.9%. Twenty-six individuals (56.5%) were symptomatic. The most frequent symptom was headache (34.8%). There were no statistically significant differences between the age groups with regard to the amount of CTH (p = 0.81). Thirteen children (28.3%) underwent surgical treatment. CTH was significantly higher in the surgical group (p < 0.01). Twenty-three patients (50%) performed a 3-year mean follow-up, 17 of whom had no surgery treatment. CTH was stable in 58.8%, reduced in three and increased in three, without any change in symptoms. Only one child showed a worsening in herniation and symptoms, then requiring surgery. CONCLUSION: Frequency and type of symptoms were consistent with those reported in the literature. Conservative approach is a viable option for minimally symptomatic patients, most of whom did not show clinical worsening at follow-up.