Imaging and health metrics in Incidental Cerebellar Tonsillar Ectopia: Findings from the Adolescent Brain Cognitive Development Study (ABCD)

Purpose. Incidental cerebellar tonsillar ectopia (ICTE) that meets the radiographic criterion for Chiari malformation type I (CMI) is an increasingly common finding in the clinical setting, but its significance is unclear. The present study examined posterior cranial fossa (PCF) morphometrics and a broad range of health instruments of pediatric ICTE cases and matched controls extracted from the Adolescent Brain Cognitive Development (ABCD) dataset. Methods. 106 subjects with ICTE and 106 matched controls without ICTE were identified from 11,411 anatomical MRI of healthy screened pediatric subjects from the ABCD project. Subjects were matched by sex, age, body mass index, race, and ethnicity. Twenty-two brain morphometrics and 22 health instruments were compared between the two groups to identify unrecognized CMI symptoms and assess the general health impact of ICTE. Results. Twelve and 15 measures were significantly different between the ICTE and control groups for females and males, respectively. Notably, for females, the anterior CSF space was significantly smaller (p = 0.00005) for the ICTE group than controls. For males, the clivus bone length was significantly shorter (p = 0.0002) for the ICTE group compared to controls. No significant differences were found among the 22 health instruments between the two groups. Conclusion. This study demonstrated that pediatric ICTE subjects have similar PCF morphometrics to adult CMI. ICTE alone did not appear to cause any unrecognized CMI symptoms and had no impact on the subjects' current mental, physical, or behavioral health. Still, given their cranial and brain morphology, these cases may be at risk for adult-onset symptomatic CMI.

Feasibility of iliosacral screw placement in patients with upper sacral dysplasia

Background Exact knowledge of the sacral anatomy is crucial for the percutaneous insertion of iliosacral screws. However, dysplastic anatomical patterns are common. In addition to a preoperative computed tomography (CT) analysis, conventional radiographic measures may help to identify upper sacral dysplasia and to avoid damage to surrounding structures. Aiming to further increase safety in percutaneous iliosacral screw placement in the presence of sacral dysmorphism, this study examined the prevalence of previously established radiographic signs and, in addition, defined the “critical SI angle” as a new radiographic criterion. Methods Pelvic CT scans of 98 consecutive trauma patients were analysed. Next to assessment of established signs indicating upper sacral dysplasia, the critical sacroiliac (SI) angle was defined in standardized pelvic outlet views. Results The critical SI angle significantly correlates with the presence of mammillary bodies and an intraarticular vacuum phenomenon. With a cut-off value of − 14.2°, the critical SI angle detects the feasibility of a safe iliosacral screw insertion in pelvic outlet views with a sensitivity of 85.9% and a specificity of 85.7%. Conclusions The critical SI angle can support the decision-making when planning iliosacral screw fixation. The clinical value of the established signs of upper sacral dysplasia remains uncertain.

Do patients with axial spondyloarthritis with radiographic sacroiliitis fulfil both the modified New York criteria and the ASAS axial spondyloarthritis criteria? Results from eight cohorts

BackgroundPatients with spondyloarthritis with radiographic sacroiliitis are traditionally classified according to the modified New York (mNY) criteria as ankylosing spondylitis (AS) and more recently according to the Assessment of SpondyloArthritis international Society (ASAS) criteria as radiographic axial spondyloarthritis (r-axSpA).ObjectiveTo investigate the agreement between the mNY criteria for AS and the ASAS criteria for r-axSpA and reasons for disagreement.MethodsPatients with back pain ≥3 months diagnosed as axSpA with radiographic sacroiliitis (mNY radiographic criterion) were selected from eight cohorts (ASAS, Esperanza, GESPIC, OASIS, Reuma.pt, SCQM, SPACE, UCSF). Subsequently, we calculated the percentage of patients who fulfilled the ASAS r-axSpA criteria within the group of patients who fulfilled the mNY criteria and vice versa in six cohorts with complete information.ResultsOf the 3882 patients fulfilling the mNY criteria, 93% also fulfilled the ASAS r-axSpA criteria. Inversely, of the 3434 patients fulfilling the ASAS r-axSpA criteria, 96% also fulfilled the mNY criteria. The main cause for discrepancy between the two criteria sets was the reported age at onset of back pain.ConclusionAlmost all patients with axSpA with radiographic sacroiliitis fulfil both ASAS and mNY criteria, which supports the interchangeable use of the terms AS and r-axSpA.

Enlargement of Post-Traumatic Intracerebral Haematoma: Incidence and Time Course

We retrospectively assessed the incidence and time course of enlargement in posttraumatic intracerebral haematoma (PTICH). Computed tomography (CT) scans from 165 patients who underwent a scan within 72 h and a repeat scan within 120 h of the onset of trauma were examined. A semi-automated method using region deformation-based segmentation was used to calculate the haematoma volume. The presence of haematoma enlargement was also determined based on a consensus by five observers. Seventy cases (42%) showed enlargement of the haematoma. The frequency of haematoma enlargement decreased as the interval between the onset of trauma and the initial scan increased. The discriminant value of the ratio of the haematoma volume in the second scan to that in the initial scan was ascertained, and the cut-off value for haematoma enlargement was determined to be 1.45. The radiographic criterion for enlargement in PTICH on CT scan was, therefore, defined as a ≥ 1.45 times increase in haematoma volume.

Traumatic Anterior Atlanto-occipital Dislocation

The five cases of atlanto-occipital dislocation reported in the world literature are reviewed, and four additional cases are presented, including two survivors. The pathological anatomy of this potentially catastrophic injury and its management are briefly discussed. Because immediate recognition of the atlanto-occipital dislocation is critical to proper treatment and because the neurological findings are extremely varied, a new radiographic criterion for its identification has been developed.