Impact of imaging modality, age, and gender on craniocervical junction angles in adults without structural pathology

Impacts of type 1 Chiari malformation on elderly

Background

This study aims to evaluate the surgical outcomes of elderly patients with Chiari malformation (CM) who underwent suboccipital craniectomy (SC) with duraplasty (DP) or dural splitting (DS). The focus is on symptom relief, changes in syrinx size, hospital admission duration, and postoperative complications.

Methods

A retrospective study was performed to evaluate the outcomes of elderly CM patients who underwent SC with DP or dural splitting (DS). Patients older than 60 years who underwent posterior fossa decompression (PFD) together with DP or DS who underwent surgery from 1989 to 2022 were included in the study. Patients were divided into two categories based on their surgical approach - SC with DP and SC with dural splitting (DS) surgery. Demographic details, co-morbidities, clinical features, management details, Chicago Chiari Outcome Scale (CCOS), complications, and follow-up details were obtained.

Results

Of the seven patients, five were females, and two were males. The mean age at the time of the operation is 65.14 years. Among the seven patients, six had syrinx, with a mean diameter of 6.17 mm; one patient had hydrocephalus, and one had scoliosis. All the patients underwent PFD; six patients also underwent DP, and one patient underwent DS. The median CCOS at the time of discharge is 13.

Conclusion

In elderly CM patients, surgery improved symptoms for most but led to reoperations in two cases. Despite a slight increase in syrinx diameter and a drop in the CCOS score, better outcomes were associated with smaller syrinxes. Further research is needed to optimize treatment strategies for this population.

Cervicogenic Dizziness Associated With Craniocervical Instability: A Case Report

Cervicogenic dizziness (CGD) is a clinical syndrome characterized by an illusory sensation of motion and disequilibrium secondary to neck pathologies. Reported here is the case of a 40-year-old male presented with neck pain, dizziness, and aural symptoms in the past 12 months. The patient was previously diagnosed with Meniere’s disease and treated with a low-sodium diet, betahistine and vestibular rehabilitation for 4 months, but the symptoms had not been relieved. Subsequently he sought out chiropractic evaluation. Radiographic clues illustrated a subtle anterolisthesis of the occiput on the cervical spine, manifested by a dissociation of the clivo-axial angle (CXA). After exclusion of other neurological, vascular and vestibular causes, craniocervical instability was considered as the cause of the CGD. He was treated with multi-component intervention consisting of spinal manipulation, intermittent motorized traction and ultrasound therapy to release cervical complaints. The patient reported salutary consequences to the 3-month treatment course with no neurologic sequelae. The current study serves as a vivid example of identifying CGD based on a subtle radiographic clue and by utilizing CXA as an assessment tool for craniocervical instability.

Normal range of clivoaxial angle in adults using flexion and extension cervical magnetic resonance imaging scans

OBJECTIVE

An abnormally decreased clivoaxial angle (CXA) is used during the clinical evaluation for corrective skull base surgery. Published normal ranges of CXA using x-ray, computed tomography, or magnetic resonance imaging (MRI) vary dramatically, especially with neck flexion or extension. The aim of this study was to use high-resolution MRI to determine the normal range of CXA in various neck positions using a reproducible measurement technique.

METHODS

The CXA was measured in 10 healthy volunteers on sagittal T2 SPACE c-spine MRI in supine and prone positions and with the neck both neck and extended. CXA is strictly defined as the angle between a line along the inferior third of the dorsal clival cortex and a line from the superior/posterior cortex of the dens to the posterior/inferior corner of the C2 body. Statistical analysis was performed in all positions and included mean CXA, range, standard deviation (SD), inter-reader agreement, and group comparisons.

RESULTS

The mean CXA overall was 156.92° (SD=4.23°; range 134-179°). The mean value for extension CXA was 169.20° (SD=5.81°), and the mean value for flexion CXA was 144.73° (SD=5.71°), the difference being statistically significant (p<0.0001) regardless of supine or prone position. Concordant correlations of reader measurements showed substantial agreement in the supine position at 0.96, with lower agreement in the prone position at 0.87.

CONCLUSIONS

We report normal ranges for CXA in various neck positions based on 3D T2-weighted MRI, using a reproducible measurement method. There was a significant difference in the CXA values between neck extended and neck flexed positions but not between supine and prone positions.