scholarly journals Morphometric and volumetric comparison of 102 children with symptomatic and asymptomatic Chiari malformation Type I

2018 ◽  
Vol 21 (1) ◽  
pp. 65-71 ◽  
Author(s):  
Siri Sahib S. Khalsa ◽  
Ndi Geh ◽  
Bryn A. Martin ◽  
Philip A. Allen ◽  
Jennifer Strahle ◽  
...  

OBJECTIVEChiari malformation Type I (CM-I) is typically defined on imaging by a cerebellar tonsil position ≥ 5 mm below the foramen magnum. Low cerebellar tonsil position is a frequent incidental finding on brain or cervical spine imaging, even in asymptomatic individuals. Nonspecific symptoms (e.g., headache and neck pain) are common in those with low tonsil position as well as in those with normal tonsil position, leading to uncertainty regarding appropriate management for many patients with low tonsil position and nonspecific symptoms. Because cerebellar tonsil position is not strictly correlated with the presence of typical CM-I symptoms, the authors sought to determine if other 2D morphometric or 3D volumetric measurements on MRI could distinguish between patients with asymptomatic and symptomatic CM-I.METHODSThe authors retrospectively analyzed records of 102 pediatric patients whose records were in the University of Michigan clinical CM-I database. All patients in this database had cerebellar tonsil position ≥ 5 mm below the foramen magnum. Fifty-one symptomatic and 51 asymptomatic patients were matched for age at diagnosis, sex, tonsil position, and tonsil morphology. National Institutes of Health ImageJ software was used to obtain six 2D anatomical MRI measurements, and a semiautomated segmentation tool was used to obtain four 3D volumetric measurements of the posterior fossa and CSF subvolumes on MRI.RESULTSNo significant differences were observed between patients with symptomatic and asymptomatic CM-I related to tentorium length (50.3 vs 51.0 mm; p = 0.537), supraoccipital length (39.4 vs 42.6 mm; p = 0.055), clivus-tentorium distance (52.0 vs 52.1 mm; p = 0.964), clivus-torcula distance (81.5 vs 83.3 mm; p = 0.257), total posterior fossa volume (PFV; 183.4 vs 190.6 ml; p = 0.250), caudal PFV (152.5 vs 159.8 ml; p = 0.256), fourth ventricle volume to caudal PFV ratio (0.0140 vs 0.0136; p = 0.649), or CSF volume to caudal PFV ratio (0.071 vs 0.061; p = 0.138).CONCLUSIONSNo clinically useful 2D or 3D measurements were identified that could reliably distinguish pediatric patients with symptoms attributable to CM-I from those with asymptomatic CM-I.

Neurosurgery ◽  
2017 ◽  
Vol 64 (CN_suppl_1) ◽  
pp. 267-267
Author(s):  
Siri Sahib S Khalsa ◽  
Ndi Geh ◽  
Bryn A Martin ◽  
Philip A Allen ◽  
Jennifer Strahle ◽  
...  

Abstract INTRODUCTION Chiari malformation type I (CMI) is typically defined by a cerebellar tonsil position 5 mm or more below foramen magnum. Low cerebellar tonsil position is a frequent incidental finding, even in asymptomatic individuals. Non-specific symptoms such as headache and neck pain are common in those with low tonsil position and in those with normal tonsil position, leading to uncertainty regarding appropriate management for many patients with low tonsil position and non-specific symptoms. Since cerebellar tonsil position is not strictly correlated with typical CMI symptoms, we sought to determine if other 2D morphometric or 3D volumetric measurements on MRI could distinguish asymptomatic from symptomatic CMI patients. METHODS We retrospectively analyzed 102 pediatric patients from the University of Michigan clinical CMI database. All patients in this database have cerebellar tonsil position at least 5 mm below foramen magnum. Fifty-one symptomatic and 51 asymptomatic patients were matched for age at diagnosis, sex, tonsil position, and tonsil morphology. Five 2D anatomic MRI measurements and four 3D volumetric measurements of posterior fossa and CSF sub-volumes on MRI were measured. RESULTS >There were no significant differences observed between symptomatic and asymptomatic CMI patients related to basilar impression (−5.9 mm vs. −7.0 mm; P = 0.026), tentorium length (50.3 mm vs. 51.0 mm; P = 0.537), supraoccipital length (39.4 mm vs. 42.6 mm; P = 0.055), clivus-tentorium distance (52.0 mm vs. 52.1 mm; P = 0.964), clivus-torcula distance (81.5 mm vs. 83.3 mm; P = 0.257), total posterior fossa volume (PFV; 183.4 mL vs. 190.6 mL; P = 0.250), caudal PFV (152.5 mL vs. 159.8 mL; P = 0.256), fourth ventricle volume to caudal PFV ratio (0.0140 vs. 0.0136; P = 0.649), or CSF volume to caudal PFV ratio (0.071 vs. 0.061; P = 0.138). CONCLUSION We did not identify any 2D or 3D measurements that could reliably distinguish pediatric patients with symptoms attributable to CMI from those with asymptomatic CMI.


2015 ◽  
Vol 123 (1) ◽  
pp. 226-231 ◽  
Author(s):  
Brandon W. Smith ◽  
Jennifer Strahle ◽  
Erick Kazarian ◽  
Karin M. Muraszko ◽  
Hugh J. L. Garton ◽  
...  

OBJECT It is unclear if there is a relationship between Chiari malformation Type I (CM-I) and body mass index (BMI). The aim of this study was to identify the relationship between BMI and cerebellar tonsil position in a random sample of people. METHODS Cerebellar tonsil position in 2400 subjects from a cohort of patients undergoing MRI was measured. Three hundred patients were randomly selected from each of 8 age groups (from 0 to 80 years). A subject was then excluded if he or she had a posterior fossa mass or previous posterior fossa decompression or if height and weight information within 1 year of MRI was not recorded in the electronic medical record. RESULTS There were 1310 subjects (54.6%) with BMI records from within 1 year of the measured scan. Of these subjects, 534 (40.8%) were male and 776 (59.2%) were female. The average BMI of the group was 26.4 kg/m2, and the average tonsil position was 0.87 mm above the level of the foramen magnum. There were 46 subjects (3.5%) with a tonsil position ≥ 5 mm below the level of the foramen magnum. In the group as a whole, there was no correlation (R2 = 0.004) between BMI and cerebellar tonsil position. CONCLUSIONS In this examination of 1310 subjects undergoing MRI for any reason, there was no relationship between BMI and the level of the cerebellar tonsils or the diagnosis of CM-I on imaging.


2018 ◽  
Vol 27 (1) ◽  
pp. 71-73
Author(s):  
Lindolfo Carlos Heringer ◽  
Matheus Fernandes De Oliveira ◽  
Ulysses Oliveira De Sousa ◽  
Wanderley Cerqueira De Lima ◽  
Ricardo Vieira Botelho

Introduction. The association between hydrocephalus and Chiari malformation (CM) has not been described frequently. Ventricular dilation affects 7% to 10% of patients with CM, but the ideal choice of surgical treatment is controversial. Wereport a case of a patient with Chiari malformation and hydrocephalus with improvement in clinical symptoms and ventricular dilatation. Case Description. A 19-year-old male complaining of frontal headache when coughing, laughing and during valsalva maneuvers, associated with dizziness for 2 months. Magnetic resonance (MR) showed hydrocephalus and small posterior fossa with overcrowding of contents, characterizing Chiari malformation type I, with cerebellar tonsils protruding through magnum foramen. Patient underwent surgery with posterior fossa decompression in a semi-sitting position and removal of the arc C1.After 3 months of follow-up, headache disappeared becoming asymptomatic. Control MR showed improvement of hydrocephalus with restoration of the cisterna magna and CSF flow. Discussion. Hydrocephalus has been related to CM for a long time. In our case, we performed treatment with intradural and intra-arachnoidal approach with bilateral tonsillectomy without placing ventricular shunt. The cisterna magna was “recreated”. There was improvement of hydrocephalus with decreased Evans ratio index and symptoms disappearance. Although there is no other studies addressing such matter, in this case, the improvement suggests that the CSF compression at the foramen magnum was the cause of associated hydrocephalus with Chiari malformation. 


2011 ◽  
Vol 8 (5) ◽  
pp. 430-437 ◽  
Author(s):  
Brandon G. Rocque ◽  
Timothy M. George ◽  
John Kestle ◽  
Bermans J. Iskandar

Object The purpose of this study was to report the results of a survey of the American Society of Pediatric Neurosurgeons (ASPN) on treatment of Chiari malformation Type I (CM-I) with syringomyelia. Methods A questionnaire was circulated during the 2006 meeting of the ASPN, in which surgeons were surveyed on their management of patients with CM-I and syringomyelia. The survey consisted of questions about 4 clinical scenarios, common causes of surgical failures, and complications. Results There were 72 respondents, representing more than 90% of attendees at the 2006 ASPN meeting and approximately half of the society's members. The majority of respondents (85%) reported that they perform posterior fossa decompression as first-line treatment for CM-I with syringomyelia. Seven percent perform bony decompression alone, 36% open the dura, and 27% shrink the tonsils. Very few respondents indicated that they offer syrinx drainage as first-line therapy (< 3%). Although all respondents reported that they treat symptomatic CM-I/syringomyelia patients surgically, 15% of respondents indicated that they do not operate on asymptomatic patients. Finally, respondents stated that their most common complications are pseudomeningocele and chemical meningitis. Conclusions This survey, given to a representative group of experienced North American pediatric neurosurgeons, confirms that posterior fossa decompression is still the preferred treatment modality in children with CM-I and syringomyelia, regardless of symptoms. Although most surgeons open the dura, preferred techniques for decompression vary. In contrast to the results of past surveys, conservative follow-up is now only used by a minority of respondents and only in the asymptomatic patient, and primary syrinx drainage seems to have lost popularity. A multicenter trial of surgical outcomes has been designed based on the information from this survey.


2017 ◽  
Vol 19 (5) ◽  
pp. 511-517 ◽  
Author(s):  
Siri Sahib S. Khalsa ◽  
Alan Siu ◽  
Tiffani A. DeFreitas ◽  
Justin M. Cappuzzo ◽  
John S. Myseros ◽  
...  

OBJECTIVEPrevious studies have indicated an association of Chiari malformation Type I (CM-I) and a small posterior fossa. Most of these studies have been limited by 2D quantitative methods, and more recent studies utilizing 3D methodologies are time-intensive with manual segmentation. The authors sought to develop a more automated tool to calculate the 3D posterior fossa volume, and correlate its changes after decompression with surgical outcomes.METHODSA semiautomated segmentation program was developed, and used to compare the pre- and postoperative volumes of the posterior cranial fossa (PCF) and the CSF spaces (cisterna magna, prepontine cistern, and fourth ventricle) in a cohort of pediatric patients with CM-I. Volume changes were correlated with postoperative symptomatic improvements in headache, syrinx, tonsillar descent, cervicomedullary kinking, and overall surgical success.RESULTSForty-two pediatric patients were included in this study. The mean percentage increase in PCF volume was significantly greater in patients who showed clinical improvement versus no improvement in headache (5.89% vs 1.54%, p < 0.05) and tonsillar descent (6.52% vs 2.57%, p < 0.05). Overall clinical success was associated with a larger postoperative PCF volume increase (p < 0.05). These clinical improvements were also significantly associated with a larger increase in the volume of the cisterna magna (p < 0.05). The increase in the caudal portion of the posterior fossa volume was also larger in patients who showed improvement in syrinx (6.63% vs 2.58%, p < 0.05) and cervicomedullary kinking (9.24% vs 3.79%, p < 0.05).CONCLUSIONSA greater increase in the postoperative PCF volume, and specifically an increase in the cisterna magna volume, was associated with a greater likelihood of clinical improvements in headache and tonsillar descent in patients with CM-I. Larger increases in the caudal portion of the posterior fossa volume were also associated with a greater likelihood of improvement in syrinx and cervicomedullary kinking.


2018 ◽  
Vol 22 (4) ◽  
pp. 426-438 ◽  
Author(s):  
Andrew C. Vivas ◽  
Nir Shimony ◽  
Eric M. Jackson ◽  
Risheng Xu ◽  
George I. Jallo ◽  
...  

OBJECTIVEHydrocephalus associated with subdural hygromas is a rare complication after decompression of Chiari malformation type I (CM-I). There is no consensus for management of this complication. The authors present a series of 5 pediatric patients who underwent CM-I decompression with placement of a dural graft complicated by posterior fossa hygromas and hydrocephalus that were successfully managed nonoperatively.METHODSA retrospective review over the last 5 years of patients who presented with hydrocephalus and subdural hygromas following foramen magnum decompression with placement of a dural graft for CM-I was conducted at 2 pediatric institutions. Their preoperative presentation, perioperative hospital course, and postoperative re-presentation are discussed with attention to their treatment regimen and ultimate outcome. In addition to reporting these cases, the authors discuss all similar cases found in their literature review.RESULTSOver the last 5 years, the authors have encountered 194 pediatric cases of CM-I decompression with duraplasty equally distributed at the 2 institutions. Of those cases, 5 pediatric patients with a delayed postoperative complication involving hydrocephalus and subdural hygromas were identified. The 5 patients were managed nonoperatively with acetazolamide and high-dose dexamethasone; dosages of both drugs were adjusted to the age and weight of each patient. All patients were symptom free at follow-up and exhibited resolution of their pathology on imaging. Thirteen similar pediatric cases and 17 adult cases were identified in the literature review. Most reported cases were treated with CSF diversion or reoperation. There were a total of 4 cases previously reported with successful nonoperative management. Of these cases, only 1 case was reported in the pediatric population.CONCLUSIONSDe novo hydrocephalus, in association with subdural hygromas following CM-I decompression, is rare. This presentation suggests that these complications after posterior fossa decompression with duraplasty can be treated with nonoperative medical management, therefore obviating the need for CSF diversion or reoperation.


2011 ◽  
Vol 7 (4) ◽  
pp. 375-379 ◽  
Author(s):  
David Benglis ◽  
Derek Covington ◽  
Ritwik Bhatia ◽  
Sanjiv Bhatia ◽  
Mohamed Samy Elhammady ◽  
...  

Object The natural history of untreated Chiari malformation Type I (CM-I) is poorly defined. The object of this study was to investigate outcomes in pediatric patients with CM-I who were followed up without surgical intervention. Methods The authors retrospectively reviewed 124 cases involving patients with CM-I who presented between July 1999 and July 2008 and were followed up without surgery. The patients ranged in age from 0.9 to 19.8 years (mean 7 years). The duration of follow-up ranged from 1.0 to 8.6 years (mean 2.83 years). Imaging findings, symptoms, and findings on neurological examinations were noted at presentation and for the duration of follow-up. Results The mean extent of tonsillar herniation at presentation was 8.35 mm (range 5–22 mm). Seven patients had a syrinx at presentation. The syrinx size did not change in these patients on follow-up imaging studies. No new syrinxes developed in the remaining patients who underwent subsequent imaging. The total number of patients with presenting symptoms was 81. Of those 81 patients, 67 demonstrated symptoms that were not typical of CM-I. Of the 14 patients with symptoms attributed to CM-I, 9 had symptoms that were not severe or frequent enough to warrant surgery, and surgery was recommended in the remaining 5 patients. Chiari malformation Type I was also diagnosed in 43 asymptomatic patients who had imaging studies performed for various reasons. No new neurological deficits were noted in any patient for the duration of follow-up. Conclusions The majority of patients with CM-I who are followed up without surgery do not progress clinically or radiologically. Longer follow-up of this cohort will be required to determine if symptoms or new neurological findings develop over the course of many years.


2018 ◽  
Vol 22 (1) ◽  
pp. 52-60 ◽  
Author(s):  
Arnold H. Menezes ◽  
Jeremy D. W. Greenlee ◽  
Brian J. Dlouhy

OBJECTIVESyringobulbia (SB) is a rare entity, with few cases associated with Chiari malformation type I (CM-I) in the pediatric population. The authors reviewed all pediatric cases of CM-I–associated SB managed at their institution in order to better understand the presentation, treatment, and surgical outcomes of this condition.METHODSA prospectively maintained institutional database of craniovertebral junction abnormalities was analyzed to identify all cases of CM-I and SB from the MRI era (i.e., after 1984). The authors recorded presenting symptoms, physical examination findings, radiological findings, surgical treatment strategy, intraoperative findings, and outcomes. SB cases associated with tumors, infections, or type II Chiari malformations were excluded.RESULTSThe authors identified 326 pediatric patients with CM-I who were surgically treated. SB was identified in 13 (4%) of these 326 patients. Headache and neck pain were noted in all 13 cases. Cranial nerve abnormalities were common: vagus and glossopharyngeal nerve dysfunction was the most frequent observation. Other cranial nerves affected included the trigeminal, abducens, and hypoglossal nerves. Several patients exhibited multiple cranial nerve palsies at presentation. Central sleep apnea was present in 6 patients.Syringomyelia (SM) was present in all 13 patients. SB involved the medulla in all cases, and extended rostrally into the pons and midbrain in 2 patients; in 1 of these 2 cases the cavity extended further rostrally to the cerebrum (syringocephaly). SB communicated with the fourth ventricle in 7 of the 13 cases.All 13 patients were treated with posterior fossa decompression with intradural exploration to ensure CSF egress out of the fourth ventricle and through the foramen magnum. The foramen of Magendie was found to be occluded by an arachnoid veil in 9 cases. Follow-up evaluation revealed that SB improved before SM. Cranial nerve palsies regressed in 11 of the 13 patients, and SB improved in all 13.CONCLUSIONSThe incidence of SB in our surgical series of pediatric patients with CM-I was 4%, and all of these patients had accompanying SM. The SB cavity involved the medulla in all cases and was found to communicate with the fourth ventricle in 54% of cases. Posterior fossa decompression with intradural exploration and duraplasty is an effective treatment for these patients.


2011 ◽  
Vol 8 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Joshua J. Chern ◽  
Amber J. Gordon ◽  
Martin M. Mortazavi ◽  
R. Shane Tubbs ◽  
W. Jerry Oakes

Object In 1998 the authors identified 5 patients with syringomyelia and no evidence of Chiari malformation Type I (CM-I). Magnetic resonance imaging of the entire neuraxis ruled out other causes of a syrinx. Ultimately, abnormal CSF flow at the foramen magnum was the suspected cause. The label “Chiari 0” was used to categorize these unique cases with no tonsillar ectopia. All of the patients underwent posterior fossa decompression and duraplasty identical to the technique used to treat patients with CM-I. Significant syrinx and symptom resolution occurred in these patients. Herein, the authors report on a follow-up study of patients with CM-0 who were derived from over 400 operative cases of pediatric CM-I decompression. Methods The authors present their 12-year experience with this group of patients. Results Fifteen patients (3.7%) were identified. At surgery, many were found to have physical barriers to CSF flow near the foramen magnum. In most of them, the syringomyelia was greatly diminished postoperatively. Conclusions The authors stress that this subgroup represents a very small cohort among patients with Chiari malformations. They emphasize that careful patient selection is critical when diagnosing CM-0. Without an obvious CM-I, other etiologies of a spinal syrinx must be conclusively ruled out. Only then can one reasonably expect to ameliorate the clinical course of these patients via posterior fossa decompression.


Sign in / Sign up

Export Citation Format

Share Document