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Yang D. Teng - One of the best experts on this subject based on the ideXlab platform.
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A Combinatorial Approach with Cerebellar Tonsil Suspension to Treating Symptomatic Chiari Malformation Type I in Adults: A Retrospective Study.
World neurosurgery, 2020Co-Authors: Lei Wang, Hongyang Zhao, Wende Zhu, Peng-fei Yan, Yang D. TengAbstract:Background Primary Chiari malformations (CMs) are congenital defects of the skull base and brain. Among the 4 CM types, type I (CM-I) occurs most frequently and may cause somatosensorimotor, autonomic and vision symptoms. Presently, posterior fossa decompression alone (PFD) or with duraplasty (PFDD) and Cerebellar Tonsil (CbT) shrinkage tactics are standard treatments, albeit inherent issues. There has been no report on devising CbT suspension (CTS) to manage CM-I. Objectives 1) To design a CTS protocol that can be used with CbT coagulation (CTC) and PFDD; 2) to evaluate the regimen for feasibility, safety, and efficacy in a retrospective study; and 3) to obtain data for planning prospective studies to validate PFDD + CTC + CTS as a novel approach to treating adult CM-I. Methods PFDD + CTC + CTS (n = 17), PFDD + CTC (n = 13), and PFDD (n = 12) were performed for 42 adult patients (age range, 18–55 years; female:male = 27:15) following a balanced study design. Neck Disability Index (NDI), Chicago Chiari Outcome Scale (CCOS), and /magnetic resonance imaging/computed tomography were used to determine postsurgery outcomes for approximately 20 months. Results Comparing to PFDD + CTC or PFDD, patients receiving PFDD + CTC +CTS operation exhibited significantly improved group average NDI (10.72 ± 3.95%; P = 0.007), CbT elevation distance (7.06 ± 2.42 mm; P Conclusions The PFDD + CTC + CTS regimen appeared to be safe and potentially more efficacious in patients with CM-I evaluated for the period, relative to PFDD + CTC or PFDD treatment. Future prospective studies were warranted.
Xu Sun - One of the best experts on this subject based on the ideXlab platform.
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Study of relationship between position of the Cerebellar Tonsil and abnormal somatosensory evoked potentials in adolescent idiopathic scoliosis
Zhonghua wai ke za zhi [Chinese journal of surgery], 2009Co-Authors: Zhi-jun Chen, Yong Qiu, Xu SunAbstract:Objective To investigate the abnormality of position of the Cerebellar Tonsil and somatosensory evoked potentials (SEP) in adolescent idiopathic scoliosis (AIS), and to explore its clinical significance. Methods Sagittal magnetic resonance imaging (MBI) of hindbrain and posterior tibial nerve SEP (PTN-SEP) were performed on 171 young operative treated AIS patients. The PTN-SEP obtained from 45 age-matched healthy control individuals were considered as standard values. Tonsillar ectopia (TE) was defined as any inferior displacement of the Tonsils. Absence of SEP waveforms, prolongation of peek latency or asymmetrical peek latency were defined as pathological change. The incidence of TE and pathological SEP was determined in all AIS patients. The association of TE and abnormal SEP for AIS patients was also assessed. Results The incidence of TE and abnormal SEP in AIS patients was 36.8% (63/171) and 36.3% (62/171), respectively. It was shown the frequency of TE and abnormal SEP were not significantly different among AIS patients with different curve severity. Statistical analysis failed to show a correlation between TE and abnormal SEP. Conclusions TE and disorder of somatosensory pathways do exist in a subgroup of AIS patients. However, there is not a significant association between TE and abnormal somatosensory function. It is suggested that TE and disorder of somatosensory function might contributes to different etiopathogenesis of AIS. Key words: Scoliosis; Evoked potentials, somatosensory; Tonsil; Adolescent; Etiopathogenesis
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Variations of the position of the Cerebellar Tonsil in idiopathic scoliotic adolescents with a cobb angle >40° : A magnetic resonance imaging study
Spine, 2007Co-Authors: Xu Sun, Yong Qiu, Zezhang Zhu, Feng Zhu, Bin Wang, Bangping QianAbstract:Study design A retrospective study was performed through measurements on MRI images in adolescent idiopathic scoliosis (AIS) patients and age-matched adolescents. Objectives To investigate the position of the Cerebellar Tonsil in AIS patients with a Cobb angle >40 degrees in comparison with age-matched healthy adolescents and to determine the relationships of the Tonsil position with age, sex, curve severity, and curve patterns. Summary of background data There have been increasing evidences implying that AIS patients may present with subtle or subclinical neurologic dysfunction and a higher incidence of Tonsillar ectopia was documented in AIS patients. However, the Tonsil position has not been clearly addressed in AIS patients with a severe curve. Methods According to the method described by Aboulezz et al, measurements of the Tonsil position relative to the magnum foramen on magnetic resonance images were performed in 203 AIS patients with a Cobb angle >40 degrees and 86 age-matched healthy adolescents. The inferior displacement of the Cerebellar Tonsil with an extent within 5 mm was defined as Tonsillar ectopia when it located below the magnum foramen. On the basis of measurement results, the incidence of Tonsillar ectopia was determined in both AIS and control groups. The associations of Tonsillar ectopia with curve severity and curve patterns for AIS patients and the relationships of the Tonsil positions with age and gender in all subjects were analyzed. Results In AIS patients and healthy controls, the median position of the Cerebellar Tonsil was 0.8 and 2.9 mm above the magnum foramen, respectively. The incidence of Tonsillar ectopia (0-4.8 mm below the magnum foramen) in AIS was found to be significantly higher than healthy adolescents (range 0-1.8 mm vs. 0-4.8 mm below the magnum foramen; ratio 34.5% vs. 5.8%; P Conclusion Tonsillar ectopia with the extent >2 mm in AIS patients should be regarded as abnormal. AIS patients had a lower Tonsil position and a higher prevalence of Tonsillar ectopia than controls, and Tonsillar ectopia was found to be associated with curve patterns. It is suggested that a lower position of the Cerebellar Tonsil might be associated with the etiopathogenesis of AIS and might contribute to subclinical neurologic dysfunction in AIS patients.
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variations of the position of the Cerebellar Tonsil in idiopathic scoliotic adolescents with a cobb angle 40 a magnetic resonance imaging study
Spine, 2007Co-Authors: Xu Sun, Yong Qiu, Zezhang Zhu, Feng Zhu, Bin Wang, Bangping QianAbstract:Study design A retrospective study was performed through measurements on MRI images in adolescent idiopathic scoliosis (AIS) patients and age-matched adolescents. Objectives To investigate the position of the Cerebellar Tonsil in AIS patients with a Cobb angle >40 degrees in comparison with age-matched healthy adolescents and to determine the relationships of the Tonsil position with age, sex, curve severity, and curve patterns. Summary of background data There have been increasing evidences implying that AIS patients may present with subtle or subclinical neurologic dysfunction and a higher incidence of Tonsillar ectopia was documented in AIS patients. However, the Tonsil position has not been clearly addressed in AIS patients with a severe curve. Methods According to the method described by Aboulezz et al, measurements of the Tonsil position relative to the magnum foramen on magnetic resonance images were performed in 203 AIS patients with a Cobb angle >40 degrees and 86 age-matched healthy adolescents. The inferior displacement of the Cerebellar Tonsil with an extent within 5 mm was defined as Tonsillar ectopia when it located below the magnum foramen. On the basis of measurement results, the incidence of Tonsillar ectopia was determined in both AIS and control groups. The associations of Tonsillar ectopia with curve severity and curve patterns for AIS patients and the relationships of the Tonsil positions with age and gender in all subjects were analyzed. Results In AIS patients and healthy controls, the median position of the Cerebellar Tonsil was 0.8 and 2.9 mm above the magnum foramen, respectively. The incidence of Tonsillar ectopia (0-4.8 mm below the magnum foramen) in AIS was found to be significantly higher than healthy adolescents (range 0-1.8 mm vs. 0-4.8 mm below the magnum foramen; ratio 34.5% vs. 5.8%; P Conclusion Tonsillar ectopia with the extent >2 mm in AIS patients should be regarded as abnormal. AIS patients had a lower Tonsil position and a higher prevalence of Tonsillar ectopia than controls, and Tonsillar ectopia was found to be associated with curve patterns. It is suggested that a lower position of the Cerebellar Tonsil might be associated with the etiopathogenesis of AIS and might contribute to subclinical neurologic dysfunction in AIS patients.
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variations of the position of the Cerebellar Tonsil in adolescent idiopathic scoliosis with severe curves a mri study
Studies in health technology and informatics, 2006Co-Authors: Xu Sun, Yong Qiu, Zezhang ZhuAbstract:This study is an investigation into the position of the Cerebellar Tonsils in AIS with severe curves and any relationship it has with age, sex, curve severity and curve pattern. Sagittal magnetic resonance imaging (MRI) of hindbrain was performed on both of 205 AIS patients with a Cobb angle greater than 40 degrees and 86 healthy controls. The position of the Cerebellar Tonsil relative to the line connecting the basion and opisthion (BO line) was measured. In AIS and controls, the mean position of the Cerebellar Tonsil was 0.9 and 2.9 mm above the BO line, respectively. The incidence of Tonsillar ectopia in AIS was found to be significantly higher than controls (34.5% versus 5.8%, p<0.001). No significant correlations were found between the position of the Cerebellar Tonsil with age or sex in AIS and controls. It was shown the position of the Cerebellar Tonsil was not significantly different among AIS patients with deferent curve severity. However, a significant lower incidence of Tonsillar ectopia (p=0.049) was found in patients with lumbar curves when compared to those with thoracic or thoracolumbar curves. In conclusion, there was a relatively lower position of the Cerebellar Tonsil together with a significant higher incidence of Tonsil ectopia in AIS patients. There was a trend that Tonsillar ectopia was more often in thoracic or thoraco-lumbar curves, suggesting that a lower position of the Cerebellar Tonsil may play an important role in the etiopathogenesis of AIS.
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Variations of the position of the Cerebellar Tonsil in adolescent idiopathic scoliosis with severe curves: a MRI study.
Studies in health technology and informatics, 2006Co-Authors: Xu Sun, Yong Qiu, Zezhang ZhuAbstract:This study is an investigation into the position of the Cerebellar Tonsils in AIS with severe curves and any relationship it has with age, sex, curve severity and curve pattern. Sagittal magnetic resonance imaging (MRI) of hindbrain was performed on both of 205 AIS patients with a Cobb angle greater than 40 degrees and 86 healthy controls. The position of the Cerebellar Tonsil relative to the line connecting the basion and opisthion (BO line) was measured. In AIS and controls, the mean position of the Cerebellar Tonsil was 0.9 and 2.9 mm above the BO line, respectively. The incidence of Tonsillar ectopia in AIS was found to be significantly higher than controls (34.5% versus 5.8%, p
Marcus A. Stoodley - One of the best experts on this subject based on the ideXlab platform.
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Cerebellar Tissue Strain in Chiari Malformation with Headache.
World neurosurgery, 2019Co-Authors: Bryden H. Dawes, Robert A. Lloyd, Jeffrey Rogers, John Magnussen, Lynne E. Bilston, Marcus A. StoodleyAbstract:Objective The pathogenesis of Chiari malformation type 1 (CM-1)—associated Valsalva headache is unknown, but it may be caused by abnormal Cerebellar Tonsil tissue strain. Advances in cardiac-gated magnetic resonance imaging (MRI) techniques such as balanced fast-field echo (bFFE) allow quantification of the motion of anatomic structures and can be used to measure tissue strain. The current study investigated the relationship between Valsalva heachache and Tonsillar motion in patients with CM-1. Methods A retrospective review of patients with CM-1 who had undergone cardiac-gated bFFE MRI was performed. Headache symptoms were retrieved from the medical records. Anatomic landmarks were manually selected on the cine bFFE, and a validated motion-tracking software was used to assess motion over the cardiac cycle in patients at rest. For each patient, displacement, strain, and strain rate were calculated for 3 anatomic segments. Patients undergoing surgery were examined before and after surgery. Results From 88 patients, a total of 108 bFFE sequences were analyzed. Valsalva headache was present in 50% of patients. Cerebellar Tonsil displacement (P = 0.003), strain (P = 0.012), and maximum strain rate (P = 0.04) were reduced after surgery (n = 20). There was no statistically significant association between tissue motion and headache symptoms. Conclusion The results of this study do not support a relationship between cardiac cycle Cerebellar strain and Valsalva headache in patients with CM-1. It is possible that Cerebellar strain related to respiratory maneuvers is associated with headache in Chiari patients. Further investigation of tissue strain is warranted because it represents a potential biomarker for outcomes after surgery.
Zezhang Zhu - One of the best experts on this subject based on the ideXlab platform.
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Variations of the position of the Cerebellar Tonsil in idiopathic scoliotic adolescents with a cobb angle >40° : A magnetic resonance imaging study
Spine, 2007Co-Authors: Xu Sun, Yong Qiu, Zezhang Zhu, Feng Zhu, Bin Wang, Bangping QianAbstract:Study design A retrospective study was performed through measurements on MRI images in adolescent idiopathic scoliosis (AIS) patients and age-matched adolescents. Objectives To investigate the position of the Cerebellar Tonsil in AIS patients with a Cobb angle >40 degrees in comparison with age-matched healthy adolescents and to determine the relationships of the Tonsil position with age, sex, curve severity, and curve patterns. Summary of background data There have been increasing evidences implying that AIS patients may present with subtle or subclinical neurologic dysfunction and a higher incidence of Tonsillar ectopia was documented in AIS patients. However, the Tonsil position has not been clearly addressed in AIS patients with a severe curve. Methods According to the method described by Aboulezz et al, measurements of the Tonsil position relative to the magnum foramen on magnetic resonance images were performed in 203 AIS patients with a Cobb angle >40 degrees and 86 age-matched healthy adolescents. The inferior displacement of the Cerebellar Tonsil with an extent within 5 mm was defined as Tonsillar ectopia when it located below the magnum foramen. On the basis of measurement results, the incidence of Tonsillar ectopia was determined in both AIS and control groups. The associations of Tonsillar ectopia with curve severity and curve patterns for AIS patients and the relationships of the Tonsil positions with age and gender in all subjects were analyzed. Results In AIS patients and healthy controls, the median position of the Cerebellar Tonsil was 0.8 and 2.9 mm above the magnum foramen, respectively. The incidence of Tonsillar ectopia (0-4.8 mm below the magnum foramen) in AIS was found to be significantly higher than healthy adolescents (range 0-1.8 mm vs. 0-4.8 mm below the magnum foramen; ratio 34.5% vs. 5.8%; P Conclusion Tonsillar ectopia with the extent >2 mm in AIS patients should be regarded as abnormal. AIS patients had a lower Tonsil position and a higher prevalence of Tonsillar ectopia than controls, and Tonsillar ectopia was found to be associated with curve patterns. It is suggested that a lower position of the Cerebellar Tonsil might be associated with the etiopathogenesis of AIS and might contribute to subclinical neurologic dysfunction in AIS patients.
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variations of the position of the Cerebellar Tonsil in idiopathic scoliotic adolescents with a cobb angle 40 a magnetic resonance imaging study
Spine, 2007Co-Authors: Xu Sun, Yong Qiu, Zezhang Zhu, Feng Zhu, Bin Wang, Bangping QianAbstract:Study design A retrospective study was performed through measurements on MRI images in adolescent idiopathic scoliosis (AIS) patients and age-matched adolescents. Objectives To investigate the position of the Cerebellar Tonsil in AIS patients with a Cobb angle >40 degrees in comparison with age-matched healthy adolescents and to determine the relationships of the Tonsil position with age, sex, curve severity, and curve patterns. Summary of background data There have been increasing evidences implying that AIS patients may present with subtle or subclinical neurologic dysfunction and a higher incidence of Tonsillar ectopia was documented in AIS patients. However, the Tonsil position has not been clearly addressed in AIS patients with a severe curve. Methods According to the method described by Aboulezz et al, measurements of the Tonsil position relative to the magnum foramen on magnetic resonance images were performed in 203 AIS patients with a Cobb angle >40 degrees and 86 age-matched healthy adolescents. The inferior displacement of the Cerebellar Tonsil with an extent within 5 mm was defined as Tonsillar ectopia when it located below the magnum foramen. On the basis of measurement results, the incidence of Tonsillar ectopia was determined in both AIS and control groups. The associations of Tonsillar ectopia with curve severity and curve patterns for AIS patients and the relationships of the Tonsil positions with age and gender in all subjects were analyzed. Results In AIS patients and healthy controls, the median position of the Cerebellar Tonsil was 0.8 and 2.9 mm above the magnum foramen, respectively. The incidence of Tonsillar ectopia (0-4.8 mm below the magnum foramen) in AIS was found to be significantly higher than healthy adolescents (range 0-1.8 mm vs. 0-4.8 mm below the magnum foramen; ratio 34.5% vs. 5.8%; P Conclusion Tonsillar ectopia with the extent >2 mm in AIS patients should be regarded as abnormal. AIS patients had a lower Tonsil position and a higher prevalence of Tonsillar ectopia than controls, and Tonsillar ectopia was found to be associated with curve patterns. It is suggested that a lower position of the Cerebellar Tonsil might be associated with the etiopathogenesis of AIS and might contribute to subclinical neurologic dysfunction in AIS patients.
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variations of the position of the Cerebellar Tonsil in adolescent idiopathic scoliosis with severe curves a mri study
Studies in health technology and informatics, 2006Co-Authors: Xu Sun, Yong Qiu, Zezhang ZhuAbstract:This study is an investigation into the position of the Cerebellar Tonsils in AIS with severe curves and any relationship it has with age, sex, curve severity and curve pattern. Sagittal magnetic resonance imaging (MRI) of hindbrain was performed on both of 205 AIS patients with a Cobb angle greater than 40 degrees and 86 healthy controls. The position of the Cerebellar Tonsil relative to the line connecting the basion and opisthion (BO line) was measured. In AIS and controls, the mean position of the Cerebellar Tonsil was 0.9 and 2.9 mm above the BO line, respectively. The incidence of Tonsillar ectopia in AIS was found to be significantly higher than controls (34.5% versus 5.8%, p<0.001). No significant correlations were found between the position of the Cerebellar Tonsil with age or sex in AIS and controls. It was shown the position of the Cerebellar Tonsil was not significantly different among AIS patients with deferent curve severity. However, a significant lower incidence of Tonsillar ectopia (p=0.049) was found in patients with lumbar curves when compared to those with thoracic or thoracolumbar curves. In conclusion, there was a relatively lower position of the Cerebellar Tonsil together with a significant higher incidence of Tonsil ectopia in AIS patients. There was a trend that Tonsillar ectopia was more often in thoracic or thoraco-lumbar curves, suggesting that a lower position of the Cerebellar Tonsil may play an important role in the etiopathogenesis of AIS.
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Variations of the position of the Cerebellar Tonsil in adolescent idiopathic scoliosis with severe curves: a MRI study.
Studies in health technology and informatics, 2006Co-Authors: Xu Sun, Yong Qiu, Zezhang ZhuAbstract:This study is an investigation into the position of the Cerebellar Tonsils in AIS with severe curves and any relationship it has with age, sex, curve severity and curve pattern. Sagittal magnetic resonance imaging (MRI) of hindbrain was performed on both of 205 AIS patients with a Cobb angle greater than 40 degrees and 86 healthy controls. The position of the Cerebellar Tonsil relative to the line connecting the basion and opisthion (BO line) was measured. In AIS and controls, the mean position of the Cerebellar Tonsil was 0.9 and 2.9 mm above the BO line, respectively. The incidence of Tonsillar ectopia in AIS was found to be significantly higher than controls (34.5% versus 5.8%, p
Peter Jun - One of the best experts on this subject based on the ideXlab platform.
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The supraTonsillar approach to the inferior Cerebellar peduncle: anatomy, surgical technique, and clinical application to cavernous malformations.
Neurosurgery, 2006Co-Authors: Michael T Lawton, Alfredo Quiñones-hinojosa, Peter JunAbstract:Objective To introduce the supraTonsillar approach, an approach that traverses the Tonsillobiventral fissure in a trajectory over the Cerebellar Tonsil to the inferior Cerebellar peduncle, and to demonstrate the utility of this approach for resecting peduncular cavernous malformations. Methods Anatomy of the Cerebellar Tonsil and surrounding fissures, arteries, and veins are reviewed using cadaveric brain specimens. The surgical approach uses the three-quarter prone position, a suboccipital craniotomy, and wide splitting of the Tonsillobiventral fissure. Results Of our experience with 171 patients with cavernous malformations, six patients had lesions in the inferior Cerebellar peduncle that were resected using the supraTonsillar approach. All cavernous malformations were removed completely and no patients experienced surgical complications or new deficits. Conclusion The supraTonsillar approach differs from the transvermian and telovelar approaches to the fourth ventricle, with a more superolateral trajectory that leads instead to the inferior Cerebellar peduncle. By splitting the Tonsillobiventral fissure and mobilizing the Tonsil inferomedially, the point of access to the lesion is deepened and transgression of normal Cerebellar tissue is minimized. This elegant approach is ideally suited to the removal of cavernous malformations.
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The supraTonsillar approach to the inferior Cerebellar peduncle: anatomy, surgical technique, and clinical application to cavernous malformations.
Neurosurgery, 2006Co-Authors: Michael T Lawton, Alfredo Quiñones-hinojosa, Peter JunAbstract:To introduce the supraTonsillar approach, an approach that traverses the Tonsillobiventral fissure in a trajectory over the Cerebellar Tonsil to the inferior Cerebellar peduncle, and to demonstrate the utility of this approach for resecting peduncular cavernous malformations. Anatomy of the Cerebellar Tonsil and surrounding fissures, arteries, and veins are reviewed using cadaveric brain specimens. The surgical approach uses the three-quarter prone position, a suboccipital craniotomy, and wide splitting of the Tonsillobiventral fissure. Of our experience with 171 patients with cavernous malformations, six patients had lesions in the inferior Cerebellar peduncle that were resected using the supraTonsillar approach. All cavernous malformations were removed completely and no patients experienced surgical complications or new deficits. The supraTonsillar approach differs from the transvermian and telovelar approaches to the fourth ventricle, with a more superolateral trajectory that leads instead to the inferior Cerebellar peduncle. By splitting the Tonsillobiventral fissure and mobilizing the Tonsil inferomedially, the point of access to the lesion is deepened and transgression of normal Cerebellar tissue is minimized. This elegant approach is ideally suited to the removal of cavernous malformations.