Management of Chiari I Deformity in Children and Adolescents: A Report from the Consensus Taskforce of the Brazilian Society of Pediatric Neurosurgery

Much controversy remains on the current management of Chiari I deformity (CID) in children, with many clinical, surgical and ethic-legal implications. The Brazilian Society of Pediatric Neurosurgery (SBNPed, in the Portuguese acronym) has put together a panel of experts to analyze updated published data on the medical literature about this matter and come up with several recommendations for pediatric neurosurgeons and allied health professionals when dealing with CID. Their conclusions are reported herein, along with the respective scientific background.

Factors predicting the occurrence of syringomyelia in patients with Chiari I malformations

Background: Chiari I malformations are defined as the downward herniation of cerebellar tonsils more than 5 mm through the foramen magnum. Syringomyelia is a common association of Chiari I malformation.Methods: This purpose of this study was to determine the various factors predicting the occurrence of syringomyelia in patients with Chiari I malformations. This retrospective study was conducted in Government medical college, Thrissur, Kerala, India. 27 patients admitted with diagnosis of symptomatic Chiari I malformations during the period of January 2015 to January 2019 were selected for the study.Results: The mean age was 22.8 years and syringomyelia was more common in patients older than 10 years (p value0.005). Females were 17(63%) and males were 10(37%) but there no difference in occurrence of syringomyelia among both sexes(p value is 0.16). Syringomyelia was present in 17(63%) cases. Association between various factors and syringomyelia measured by calculating P value which was 0.005 for age >10 years, 0.16 for sex, 0.093 for duration of symptoms >12 months, 0.05 for tonsillar descend >10mm and 0.097 for hypertension. The p value for the association of duration of symptoms >12months and extend of tonsillar descend is 0.001 Mean duration of symptoms (onset of first symptom to the time of presentation) was 16.3 months and syringomyelia was more common in patients with duration of symptoms more than 12 months but this difference was statistically not significant (p value 0.093). Mean tonsillar descend from the level of foramen magnum was 11.3 mms and syringomyelia was more common in patients with tonsillar herniation more than 10mm (p value 0.05). There is a statistically significant relationship between duration of symptoms more than 12 months and tonsillar descend more than 10mm(p value 0.001).There is no significant association between hypertension and occurrence of syringomyelia in patients with Chiari I malformation.Conclusions: Incidence of Chiari I Malformations is more among adults and it is slightly higher in females. Syringomyelia is a common association of Chiari I Malformations. The occurrence of syringomyelia in patients with Chiari I Malformations associated with increasing age of patients and extend of tonsillar herniation. There is no statistically significant association between syringomyelia and duration of symptoms or hypertension.

3-D simulation of posterior fossa reduction in Chiari I / Simulação em 3D da redução da fossa posterior no Chiari do tipo I

ABSTRACT We proposed a 3D model to evaluate the role of platybasia and clivus length in the development of Chiari I (CI). Using a computer aided design software, two DICOM files of a normal CT scan and MR were used to simulate different clivus lengths (CL) and also different basal angles (BA). The final posterior fossa volume (PFV) was obtained for each variation and the percentage of the volumetric change was acquired with the same method. The initial normal values of CL and BA were 35.65 mm and 112.66º respectively, with a total PFV of 209 ml. Ranging the CL from 34.65 to 29.65 – 24.65 – 19.65, there was a PFV decrease of 0.47% – 1.12% – 1.69%, respectively. Ranging the BA from 122.66º to 127.66º – 142.66º, the PFV decreased 0.69% – 3.23%, respectively. Our model highlights the importance of the basal angle and clivus length to the development of CI.

RESUMO No presente estudo, propusemos a criação de um modelo computacional em 3D com elaboração de software onde dois arquivos em formato DICOM com uma TC e RNM de crânio foram usados para simular diferentes mensurações na extensão do clivus (EC) e no ângulo basal (AB). O volume final da fossa posterior (VFP) foi obtido em cada variação, bem como a percentagem de volume alterada. O tamanho inicial da EC era de 35,65 mm e o do AB era de 112.66º, com um VFP de 209 ml. Variando a EC de 34,65 para 29,65 – 24.65 e 19.65, houve uma diminuição do VFP de 0.47%, 1.12% e 1.69%, respectivamente. Variando o AB de 122,66º para 127,66º e 142,66º, o VFP diminui para 0.69% e 3.23%, respectivamente. Nosso modelo enfatiza a importância da patogênese do aumento do AB e do encurtamento do clivus no desenvolvimento do Chiari I.

Arnold Chiari I Malformation with Tip-Toe Gait: A Case Report

The Arnold-Chiari type I malformation has many symptoms such as headache, neck pain, gait impairment, abnormal movements or postures. But a few cases reported association of specific symptom including headache, neck pain, vertigo or ataxia. We report a case of 12 year-old boy presenting with tip-toe gait. Magnetic resonance imaging (MRI) study of brain and spine revealed underlying Arnold-Chiari type I malformation. This case shows that it is need for central nervous system evaluation in patients with changes of lower extremities tone.

Manifestações otoneurológicas tardia da malformação de Chiari I / Late otoneurologic manifestations of Chiari I malformation

INTRODUÇÃO: A malformação de Chiari (MAC) pertence a um grupo de anomalias que envolvem as estruturas da junção crâniocerebelomedular. O tipo I (MAC I) é caracterizado pela descida das tonsilas cerebelares e da porção medial do lobo inferior do cerebelo pelo canal cervical. Na literatura, têm sido descritas manifestações motoras, sensoriais e autonômicas (5). É encontrada com mais frequência em mulheres. Sua prevalência é difícil de definir, pois existem muitos casos assintomáticos, o que torna escassa a informação epidemiológica (3). OBJETIVO: O objetivo do trabalho foi relatar um caso de malformação de Chiari tipo I em uma paciente de 66 anos. RELATO DE CASO: Os autores relatam um caso de malformação de Chiari tipo I, em paciente de 66 anos, com sintomas de zumbido, hipoacusia e cefaleia occipital. COMENTÁRIOS FINAIS: A hipótese diagnóstica de Chiari tipo I deve ser embasada nas queixas do paciente, no exame clínico e de imagens, sendo a prevalência desta enfermidade de difícil definição, podendo haver diagnóstico em raras faixas etárias.

INTRODUCTION: Chiari malformation (CM) belongs to an anomaly group comprised of the structures in the cranial-cerebellarmedullary junctions. Type I (CM I) is characterized by the descent of the cerebellar tonsils and the medial portion of the lower cerebellar lobe through the cervical spinal canal. In literature, motor, sensorial and autonomous manifestations have been described. It is mostly found in women. Its prevalence is hard to determine, since there are many asymptomatic cases, hence, making the epidemiologic information scarce. OBJECTIVE: The objective of this work was to report a Chiari I malformation case in a 66-year-old female patient. CASE REPORT: Authors report a Chiari I malformation case in a 66-year-old female patient, showing tinnitus, hearing loss and occipital headache symptoms. FINAL COMMENTS: Chiari I's diagnostic hypothesis must be based on the patient's complaints, clinical and image examinations, and since the prevalence of this disease is difficult to determine, there can be diagnoses in rare age groups.

Arnold-Chiari Type I Malformation with Hemihypertrophy: A case report

The association between Arnold-Chiari type 1 malformation and hemihypertrophy has not been appreciated but a few case reports have suggested their association and proposed a common pathogenesis of dysembryoplasia of mesoderm. We report a case of 17 year-old girl presenting with left side hemihypertrophy and scoliosis. Magnetic resonance imaging (MRI) study of brain and spine revealed underlying Arnold- Chiari type 1 malformation and syringomyelia. The purpose of this paper is to emphasize the need for central nervous system evaluation in patients with hemihypertrophy.

Amigdalopexia cerebelosa en el manejo de la malformación de chiari de tipo I / Cerebellar amygdalopexy in the management of Chiari I malformation

Antecedentes. El tratamiento de la malformación de Chiari de tipo I asociada a siringomielia es controvertido. En este trabajo se presenta un análisis clínico, quirúrgico y radiológico de los pacientes con esta afección que fueron manejados durante un periodo de doce años. Material y métodos. Se incluyeron 48 pacientes, donde se encontró un discreto predominio en el sexo femenino. El cuadro clínico estuvo dominado por cefalea, dolor cervical, signos y síntomas cerebelosos, afección de nervios craneales bajos y lesión de la vía piramidal. Resultados. Tanto el grado de descenso amigdalino como el tamaño de la siringomielia fueron muy variables, sin encontrar correlación entre ambos. La cirugía consistió en una craniectomía occipital, laminectomía de C1, ascenso de amígdalas cerebelosas mediante coagulación bipolar y plastía de duramadre. Los mejores resultados clínicos se obtuvieron en el dolor y los síntomas cerebelosos, mientras que los peores fueron en la afección de los nervios craneales bajos y de la vía piramidal, sin embargo, en la gran mayoría de los pacientes se logró detener la progresión de los síntomas. No se presentaron complicaciones serias en el presente estudio. Conclusión. El procedimiento propuesto ofrece una alternativa segura, efectiva y comparable con otros métodos más riesgosos para el manejo de esta malformación.

BACKGROUND: The treatment of Chiari I malformation associated with syringomyelia is controversial. OBJECTIVE: We describe a series of patients with this disease treated during a twelve-year period. We also present clinical, surgical and radiological findings. MATERIAL AND METHODS: Forty eight patients were included; a non significant female predominance was found. Clinical course was characterized by headache, cerebellar signs and symptoms, neck pain and involvement of lower cranial nerves and pyramidal tract. The degree of tonsillar descent and syringomyelia size varied and a correlation between them was not found. Surgery consisted in an occipital craniectomy, C1 laminectomy and tonsillar elevation through bipolar coagulation and duraplasty. RESULTS: The best results were observed in pain and cerebellar symptoms, while a deficit of lower cranial nerves and pyramidal tract were observed. However, in most patients we were able to slow symptom progression. No adverse effects were documented. CONCLUSIONS: The surgicalprocedureproposed herein is an effective and safe treatment alternative for this malformation, and its results are comparable to other riskier procedures.

Neuropathic Arthropathy Induced by Syringomyelia due to Arnold-Chiari I Malformation: A case report

Neuropathic arthropathy is a chronic and progressive disease of bone and joints. One of the most common causes of neuropathic arthropathy is syringomyelia. Syringomyelia associated with Arnold-Chiari I malformation has been well documented in many reports. We report a case of 76 year-old woman presented with the right elbow joint pain and stiffness. Her symptom was caused by neuropathic arthropathy associated with Arnold-Chiari I malformation and syringomyelia. The purpose of this paper is to emphasize that neuropathic arthropathy requires the evaluation of central nervous system to assess for occult causal lesion.

Application of ventriculoperitoneal shunt as a treatment for hydrocephalus in a dog with syringomyelia and Chiari I malformation

A twenty-month-old Chihuahua male dog was presented to us suffering with ataxia. Based on the physical examination, X-ray and magnetic resonance imaging (MRI) examinations, we diagnosed the dog with hydrocephalus, Chiari I malformation and syringomyelia. Treatment consisted of internal medical treatment and the placement of a ventriculoperitoneal (VP) shunt. The ventricular dilatation was relieved and the dog improved neurologically; however, the Chiari I malformation and syringomyelia remained after surgically positioning the VP shunt.

Clinical observations of duraplasty using synthetic dural substitute or autologous fascia lata for treating Chiari I malformation complicated with syringomyelia / 中国微创外科杂志

Objective To evaluate the curative effects and complications of synthetic dural substitute (Neuro-Patch) in the surgical treatment of Chiari type I malformation (CMI) complicated with syringomyelia (SM). Methods .Forty patients suffered from CMI with SM were given foramen magnum decompression and duraplasty between June 2002 and June 2004. The duraplasty was performed using either synthetic dural substitute (Neuro-Patch Group, n=20) or autologous fascia lata (Autologous Group, n= 20). Results .Symptoms were improved in 17 patients in both of groups (85.0%) at 6 months postoperatively, and no deterioration of symptoms was seen. Postoperative pyrexia occurred in 12 patients in the Neuro-Patch Group (60.0%) and 9 patients in the Autologous Group (45.0%), without significant differences (?2=0.902,P=0.342). No statistically significant differences were observed between the Neuro-Patch Group and the Autologous Group in the operating time (3.6?0.7 h vs. 3.4?0.4 h; t=1.109,P=0.274), the time to the onset of postoperative pyrexia (7.3?3.4 d vs. 9.4?2.5 d;t=-1.560,P=0.135), the length of duration of postoperative pyrexia (range, 1~19 d vs. 1~8 d, median, 4.5 d vs. 2 d;z=-1.643,P=0.100), the drainage time (1.3?0.5 d vs. 1.2?0.4 d; t=0.230, P=0.820), the drainage volume (range, 15~300 ml vs. 20~250 ml, median, 80 ml vs. 37.5 ml; z=-1.359,P=0.174), the duration of antibiotic administration (15.8?4.8 d vs. 13.7?1.5 d;t=1.260,P=0.223), and the assessment outcomes of curative effects. The length of duration of hormone requirement was longer in the Neuro-Patch Group (12.8?4.1 d) than in the Autologous Group (7.8?3.1 d) (t=3.055, P=0.007). On MRI examinations at 6 postoperative months, no posterior cranial fossa effusion was detected in both of groups. Follow-up checkups for 9 months ~ 2 years in the 40 patients showed delayed infectious granuloma on the wound in 1 patient in the Autologous Group, which was cured by debridement. Conclusions .The Neuro-Patch is a reliable dural substitute for repairing of dural defects in the treatment of CMI associated with syringomyelia.

Chiari I Malformation Associated with Syringomyelia Treated with Foramen Magnum Decompression

The authors report two cases of Chiari I malformation associated with syringomyelia. The first is that of a 45-year-old woman with neck and shoulder pain and the other, a 24-year-old man with neck pain. In the former, MRI revealed caudal descent of the cerebellar tonsil to the C2 level and a large eccentric syrinx from the C2-T6 levels ; in the man, MRI showed caudal descent of the cerebellar tonsil to the C2 level and a large eccentric syrinx from the C2-T4 levels. We successfully treated these patients by foramen magnum decompression and duroplasty. Theories of Chiari I malformation associated with syringomyelia, as well as clinical signs and symptoms, and management techniques, are discussed.