Craniocervical Junction Malformation Research Articles

Application of aided three-dimension CT navigation system in craniocervical junction malformation disease surgery

To investigate the related problems of three-dimension CT navigation system applied to craniocervical junction malformation diseases surgery. The clinical data of 61 patients with craniocervical junction malformation disease who underwent surgical treatment from July 2015 to March 2018 was retrospectively analyzed. There were 39 males and 22 females aged from 25 to 73 years old with a mean of (46.20±12.09) years. According to the different ways of screw placements, these patients were divided into navigation group (30 cases) and non navigation group (31 cases). The screws insertion in the navigation group were guided under three-dimension CT computer-aided navigation system, while the screws insertion were guided by C-arm fluoroscopy and intraoperative anatomical landmarks in non-navigation group. All surgeries were performed by the same group of surgeons. All cases were scanned by CT after operation to assess the accuracy of the screw insertion. A total of 122 screws were inserted in the study, including 60 screws in navigation group and 62 screws in non-navigation group. The screw positions in navigation group were all satisfactory, and there were no screw-related complications. The position of 3 screws (4.83%) in non-navigation group was not satisfactory, and there was no obvious neurological symptoms after operation. The operation time of navigation group was from 87.5 to 112.5 min with a mean of (99.6± 12.0) min;and non-navigation group was from 87.5 to 107.5 min, with a mean of (97.5±10.5) min. There was no statistically significant difference in the operation time between two groups (P>0.05). The screw insertion time in navigation group was from 1.50 to 4.20 min, with a mean of (2.51±1.02) min;and non navigation group was from 1.80 to 5.10 min, with a mean of (3.25±1.05) min. The screw insertion time in navigation group was shorter than that in non-navigation group (P<0.05). The intraoperative blood loss in navigation group was from 122 to 153 ml, with a mean of (137.57±9.48) ml, which in non-navigation group wasfrom 121 to 158 ml, with a mean of (138.75±8.56) ml, there was no statistically significant difference between two groups (P>0.05). The three-dimensional CT computer-aided navigation system has the characteristics of clear imaging and accurate positioning, which can help improve the accuracy and safety of the screw insertion in craniocervical junction malformation disease surgery.

Os odontoideum: diagnosis and role of imaging.

To elucidate the imaging manifestations of os odontoideum, establish the diagnosis and guide surgical therapy. Clinical and imaging data, including X-ray, CT and MR of 24 patients with os odontoideum, were retrieved and reviewed retrospectively. Os odontoideum with intact cortex was divided into round, conical and blunt tooth types. Four cases of orthotopic and 20 cases of dystopic os odontoideum were included. There was anterior displacement of the base of the dens in six cases, posterior displacement in nine cases and no displacement in nine cases. A widening of anterior atlanto-axial space was shown in 14 patients with varying degrees. Thickening of the soft tissue posterior to the dens was observed in 19 patients, spinal canal stenosis in 21 patients, cervical myelopathy in 10 patients and craniocervical junction malformation in 9 patients. Posterior C1-C2 pedicle screw fixation and fusion was performed in 12 patients and 4 patients underwent posterior occipito-cervical fixation and fusion. Radiographically, os odontoideum is defined as an independent ossicle of variable size with smooth circumferential cortical margins separated from the axis. Imaging can be used to assess atlanto-axial instability, associated normal or abnormal anatomical structures and guide surgical therapy.

The simple posterior operation for different types of malformations in the craniocervical junction with atlantoaxial dislocation

Objective: To explore the therapeutic effect of simple posterior reduction and decompression technique for different types of malformations in the craniocervical junction with atlantoaxial dislocation. Methods: The clinical data of 34 cases of different malformations in the craniocervical junction who were treated by the simple posterior internal fixation and decompression surgery in the department of neurosurgery of the first affiliated hospital of Nanchang University from March 2014 to March 2017 were analyzed retrospectively.In 34 cases, including 26 cases of basilar invagination with atlantoaxial dislocation (19 cases with atlanto occipital fusion, 12 cases with Chiari malformation, 13 cases with syringomyelia), 8 cases of odontoid malformation with atlantoaxial dislocation (2 cases with Chiari malformation, 1 case with flat skull base, 1 case with malformation of atlas). All the cases were performed Dynamic position X-ray film, CT scan and Three-dimensional reconstruction, and craniocervical MRI scan before the operation.The enlarged decompression of the occipital foramen, the fixation and fusion of the occipitocervical were performed during the operation, and the patients with cerebellar tonsillar hernia were performed decompression of the occipital small bone window. Results: All patients were followed up after the operation.The symptoms were obviously improved in 29 cases (85.3%), stability and no change in 5 cases (14.7%) and none postoperative neurological deterioration cases. Conclusion: The treatment of craniocervical junction malformation using simple posterior reduction and decompression technique is effective and has few complications, which can obviously improve the life quality of the patients.

Psychogenic headache and analysis of 65 cases with craniocervical junction malformation operated

IntroductionCraniocervical junction (CCJ) malformations are common pathologies in Northeast of Brazil, predominating Basilar Invagination (BI) and Chiari Malformation (CM), sometimes associated to syringomielia (SM).AimsAnalyse the headache pattern in cases with CCJ malformation operated.MethodsRetrospective study of 65 cases with CCJ malformation, operated between 1994 and 2015, with analysis of headache pattern.ResultsOf 65 cases operated, 29 patients (44.6%) had BI and CM, 26 (40%) had BI, CM and SM, 2, only CM and 1, CM and SM. Of all patients, 39 (49.2%) presented headache and 43 (66.1%), nuchal pain. Among those who presented BI and CM, 12 (41.4%) presented headache and nuchal pain association. Of 26 with BI, CM and SM associated, 11 (42.3%) presented headache and nuchal pain association. We notice yet the presence of brachycephaly in 44 cases (67,7%) and brevis collis in 42 (64.6%). Headache, nuchal pain, brachycephaly and brevis collis were all present in 9 patients (31%) of BI and MC group, and in 8 (30.8%) of IB, CM and SM group.ConclusionsSeveral denominations referred to psychogenic headache: muscle contraction headache, stress headache and, finally, tension headache, well defined in the classification of International Headache Society (IHS) with clear diagnosis criteria. Bilateral location, predominantly occipital, is an important differential diagnosis with holocranial headache or occipital secondary to craniocervical malformations, and when associated to brachycephaly and brevis colis, should be carefully investigated. Diagnostic failure in symptomatic or neurological deficit’ patients can sequelae due to chronic compression of structures adjacent to CCJ.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Atlas Assimilation Patterns in Different Types of Adult Craniocervical Junction Malformations.

Study Design.This is a cross-sectional analysis of resonance magnetic images of 111 patients with craniocervical malformations and those of normal subjects.Objective.To test the hypothesis that atlas assimilation is associated with basilar invagination (BI) and atlas's anterior arch assimilation is associated with craniocervical instability and type I BI.Summary of Background Data.Atlas assimilation is the most common malformation in the craniocervical junction. This condition has been associated with craniocervical instability and BI in isolated cases.Methods.We evaluated midline Magnetic Resonance Images (MRIs) (and/or CT scans) from patients with craniocervical junction malformation and normal subjects. The patients were separated into 3 groups: Chiari type I malformation, BI type I, and type II. The atlas assimilations were classified according to their embryological origins as follows: posterior, anterior, and both arches assimilation.Results.We studied the craniometric values of 111 subjects, 78 with craniocervical junction malformation and 33 without malformations. Of the 78 malformations, 51 patients had Chiari type I and 27 had BI, of whom 10 presented with type I and 17 with type II BI. In the Chiari group, 41 showed no assimilation of the atlas. In the type I BI group, all patients presented with anterior arch assimilation, either in isolation or associated with assimilation of the posterior arch. 63% of the patients with type II BI presented with posterior arch assimilation, either in isolation or associated with anterior arch assimilation. In the control group, no patients had atlas assimilation.Conclusion.Anterior atlas assimilation leads to type I BI. Posterior atlas assimilation more frequently leads to type II BI. Separation in terms of anterior versus posterior atlas assimilation reflects a more accurate understanding of the clinical and embryological differences in craniocervical junction malformations.Level of Evidence: N/A

Revision surgery for patients after inappropriate posterior fossa decompression for craniocervical junction malformation

Objective To evaluate the revision surgical techniques with intraoperative CT navigation system for the treatment of craniocervical junction malformation after inappropriate excessive posterior fossa decompression.Methods 12 patients with Chiari Ⅰ malformation,basilar invagination and syringomyelia,after extensive posterior fossa decompression received the revision surgery from April 2009 to March 2012.The clinical presentation,treatment and follow-up results of the patients were retrospectively studied.Results The 12 patients included 5 females and 7 males.The mean age was 37.4 years.The most common symptom was motor deficit in 12 patients.Syringomyelia occurred in 8 patients.Three patients got cerebellar ptosis.8 patients were performed the posterior fixation and fusion in a reduced position with the intraoperative CT and neuronavigation.4 patients with irreducible craniovertebral junction were only performed the posterior occipitocervical fixation,whereas 1 patient was performed the posterior occipitocervical fixation,and a transoral odontoidectomy was performed as the second procedure.During 9-24 months of follow-up,solid bone fusion was observed between the occipital bone and axis in all patients.The syringomyelia in 7 patients was improved.The cerebellar ptosis of 3 patients was resolved.The range of McCormick grade was Ⅰ-Ⅲ and the range of 6 months postoperative KPS score was 80-100.Conclusions It was necessary that simultaneous fixation and fusion after an appropriate posterior decompression in patients of basilar invagination associated with Chiari malformation.The revision occipitocervical fixation and fusion with the intraoperative CT and neuronavigation for the treatment of craniocervical junction malformation after inappropriate excessive posterior fossa decompression could be successfully performed. Key words: Arnold chiari malformation type Ⅰ; Fixation; Neuronavigation; Intraoperative computed tomography

Angular craniometry in craniocervical junction malformation

The craniometric linear dimensions of the posterior fossa have been relatively well studied, but angular craniometry has been poorly studied and may reveal differences in the several types of craniocervical junction malformation. The objectives of this study were to evaluate craniometric angles compared with normal subjects and elucidate the main angular differences among the types of craniocervical junction malformation and the correlation between craniocervical and cervical angles. Angular craniometries were studied using primary cranial angles (basal and Boogard’s) and secondary craniocervical angles (clivus canal and cervical spine lordosis). Patients with basilar invagination had significantly wider basal angles, sharper clivus canal angles, larger Boogard’s angles, and greater cervical lordosis than the Chiari malformation and control groups. The Chiari malformation group does not show significant differences when compared with normal controls. Platybasia occurred only in basilar invagination and is suggested to be more prevalent in type II than in type I. Platybasic patients have a more acute clivus canal angle and show greater cervical lordosis than non-platybasics. The Chiari group does not show significant differences when compared with the control, but the basilar invagination groups had craniometric variables significantly different from normal controls. Hyperlordosis observed in the basilar inavagination group was associated with craniocervical kyphosis conditioned by acute clivus canal angles.

Treatment strategies for complicated craniocervical junction malformations

To explore the treatment strategies for complicated craniocervical junction malformations with diverse clinical and imaging features. The clinical data of 67 cases of complicated craniocervical junction malformation treated between January 2000 to December 2010 were retrospectively analyzed. Based on their clinical manifestations and imaging findings, different operative procedures were adopted, including odontoidectomy via transoral transpharyngeal approach (n = 3), occipito-cervical fusion and(or) suboccipital decompression (n = 19) and odontoidectomy via transoral transpharyngeal approach followed by occipito-cervical fusion in two-stage operation (n = 25). Four cases underwent merely odontoidectomy via transoral transpharyngeal approach and died postoperatively. Sixteen cases had occipito-cervical fusion and(or) transorally surgical release for reduction in one stage. Clinical symptoms significantly improved in 19 cases, partially improved in 21 cases and remained unchanged in 12 cases. Nine cases deteriorated postoperatively and 6 cases died. The effective rate was 59.7%. The complexity of craniocervical junction malformations may be fully assessed based on different clinical manifestations and thorough imaging studies. Then personalized operative plans are to be designed.

Craniocervical junction malformation in a child with Oromandibular-limb hypogenesis-Möbius syndrome

We report a male child with Oromandibular-limb hypogenesis (OMLH), the main features being bilateral sixth and seventh nerve palsies, limb anomalies and hypoplasia of the tongue. Additional features were shortness of the neck associated with torticollis. Radiographs of the cervical spine were non-contributory, but 3D computed tomography (CT) scanning of this area identified: a) congenital hypoplasia of the atlas; b) the simultaneous development of occiput-atlas malformation/developmental defect. To our knowledge, this is the first clinical report assessing the cervico-cranium malformation in a child with OMLH-Möbius syndrome.

Management of craniocervical junction dislocation

The discovery of a craniocervical junction malformation requires management in three steps: (1) The patterns must be recognized using tomographic measurements (Chamberlain's line, Wackenheim's line). Dynamic flexion-extension studies are necessary to assess stability or instability. Stable patterns range from platybasia to basilar invagination, with gradual deformation, and are frequently associated with Chiari malformation. Unstable patterns characterized by odontoid instability are the equivalent of an odontoid fracture. The origin is malformative (hypoplasia, aplasia of the dens, os odontoidum), but the last may be difficult to distinguish from an old odontoid fracture. They are found in many syndromes (Down, Morquio, etc.). Unstable atlantoaxial patterns with atlas assimilation are hardly reducible; they evolve toward progressive instability. (2) The neurological consequences must be defined from the clinical features of the spinal cord and the cranial nerves. Both static and dynamic MRI scans must be performed; in this way identification of the neural abnormalities (hydromyelia, Chiari, etc.) and of the osseous compression is possible. (3) The most appropriate operative procedure must be selected: stable platybasia with a nervous compression by Chiari is cured only by posterior decompression; odontoid instability is cured by reduction and posterior fixation, using hooks and autologous bone grafts on the posterior arches of C-1 and C-2. Sometimes a transarticular screw fixation of C1-2 is necessary if there is a defect on the C-1 posterior arch. Craniocervical dislocations with assimilation of the atlas require posterior occipito-vertebral bony fixation with grafts and external halo immobilization or internal fixation with hooks or screws, with anterior transoral decompression in a second step.

Craniocervical junction malformation treated by transoral approach. A survey of 25 cases with emphasis on postoperative instability and outcome.

An experience with 25 consecutive cases of craniocervical junction (CCJ) malformations operated upon via the transoral route is reported. Twenty-two patients also underwent posterior occipito-cervical stabilization with alloplastic material and in only one patient was transoral odontoidectomy and fusion with bone autograph performed. Indication for the transoral route consisted of an irreducible ventral compression of the cervicobulbar junction by the abnormal bone complex. Two patients died during the early postoperative period and the remaining 23 survivors were followed for an average of 3.5 years: 17 of these showed marked improvement and 5 a stabilization of the neurological disturbances. A further patient, who refused posterior stabilization, eventually died because of progressive cranial settling. Long-term results have shown this approach to be decisive in the surgical management of well-selected CCJ anomalies.