Age-related variations in opening pressure in lumbar puncture: Implications for its interpretation in children

INTRODUCTION

Opening pressure in lumbar puncture (LP) is an important parameter in the diagnosis of various neurological diseases. In children pressures may vary according to age. This study aimed to analyze the variation of opening pressure in LP according to age in children.

METHODS

All LPs performed between February 2017 and March 2023 were analyzed. Patients with modifying factors for opening pressure were excluded. Descriptive analysis was conducted, along with a comparison of means and medians, local regression, and quantile regression. To identify the most relevant cutoff points, graphical analyses were employed.

RESULTS

The median opening pressure was 21.0 cm H2O, with a 10th percentile (P10) of 10 and a 90th percentile (P90) of 32. An increase in opening pressure with age was found. Graphical analysis revealed a significant cutoff point at 96 months. The median opening pressure from 1 to 96 months of age was 19.2 cm H2O, with a P10 of 8 and a P90 of 28.9. For children older than 96 months, the median was 22 cm H2O, with a P10 of 11.8 and a P90 of 35.

CONCLUSION

Opening pressures in children vary with age, with no differences related to sex. Graphical analysis indicates that 96 months of age is an important cutoff point. Above this age, standard values could be used, up to 96 months of age, however, it is necessary to conduct studies for reference values. Opening pressure alone is not sufficient for the diagnosis of intracranial hypertension in children.

Prevertebral Soft Tissue Thickness of the Cervical Spine in Children: An Insensitive but Specific Aid in the Diagnosis of Occult Trauma

BACKGROUND

The purpose of this study was to investigate the sensitivity and specificity of current cervical prevertebral soft tissue swelling (PVST) values in a cohort of children with known cervical fractures or dislocations.

METHODS

Forty two children (average age 11.9, range 1.4 to 17.0 y) with documented cervical spine injury and 61 children (average age 11.9, range 0.5 to 17.9 y) with cervical pain but no injury were reviewed (January 2004 to December 2015). PVST was measured on lateral cervical radiographs at C2, C3, and C6. Patients were stratified by age (0 to 2 y, 3 to 6 y, 7 to 10 y, 11 to 15 y, and 16 y and above). The Wilcoxon rank sum test was used to compare PVST measurements at each spine level across injury and noninjury cohorts. Sensitivity and specificity were estimated to assess the ability of abnormal reference values to detect when a true injury was present. In addition, positive predictive value and negative predictive value were also estimated.

RESULTS

The majority of c-spine injuries (31/42; 76%) involved bony fracture and 57% (24/42) were treated with a collar or brace. Comparison of PVST measurement found no difference at C2 ( P =0.07), C3 ( P =0.07), or at C6 ( P =0.99) across injury and non-injury cohorts. Sensitivity was poor at single-level measures for C2 (26%), C3 (31%), and C6 (24%), while specificity was relatively high (92%, 87%, and 79%, respectively). When an increased value at either C2 or C3 indicated injury, sensitivity increased to 36%, and when an increased measurement at just one of the 3 measured levels indicated injury, the sensitivity increased to 48%, while the specificity decreased to 72%. While retropharyngeal measures were more likely to detect injury than retrotracheal, C6 alone was increased in 5 of the 20 injury patients.

CONCLUSIONS

PVST measurements exhibit poor sensitivity but good specificity as indicators for the diagnosis of occult cervical trauma in children. Negative values do not exclude injury; positive values suggest further evaluation.

LEVELS OF EVIDENCE

Level III.

Assessing Bone Quality of the Spine in Children with Scoliosis Using the Ultrasound Reflection Frequency Amplitude Index Method: A Preliminary Study

Osteopenia is considered a common phenomenon in patients who have scoliosis. Quantitative ultrasound has been used to assess skeletal status for decades, and recently ultrasound imaging using reflection signals from vertebrae were as well applied to measure spinal curvatures in children with scoliosis. The objectives of this study were to develop a new method that can robustly extract a parameter from ultrasound spinal data for estimating bone quality of scoliotic patients and to investigate the potential of the parameter in predicting curve progression. The frequency amplitude index (FAI) was calculated based on the spectrum of the original radiofrequency signals reflected from the tissue-vertebra interface. The correlation between FAI and reflection coefficient was validated using decalcified bovine bone samples in vitro, and the FAIs of scoliotic subjects were investigated in vivo with reference to body mass index, Cobb angles and curve progression status. The results revealed that the intra-rater measures were highly reliable between different trials (intra-class correlation coefficient = 0.997). The FAI value was strongly correlated with the reflection coefficient of bone tissue (R² = 0.824), and the lower FAI indicated the higher risk of curve progression for the non-mild scoliosis cases. This preliminary study found that the FAI method can provide a feasible and robust approach to assessment of the bone quality of spine and may be a promising factor in monitoring curve progression of patients who have adolescent idiopathic scoliosis.

Diagnostic Accuracy of Dual-Layer Spectral CT Using Electron Density Images to Detect Post-Traumatic Prevertebral Hematoma of the Cervical Spine

PURPOSE

 To investigate the diagnostic value of dual-layer spectral detector computed tomography (SDCT) in detecting posttraumatic prevertebral hematoma of the cervical spine by including electron density images.

METHODS

 38 patients with post-traumatic imaging of the cervical spine were included in this study and received both SDCT and MRI examinations. MRI was set as the reference and combined conventional/electron density (C + ED) images were compared to conventional CT (CCT) images alone.

RESULTS

 A total of 18 prevertebral hematomas were identified. Reader 1 identified 14 of 18 and reader 2 15 of 18 prevertebral hematomas by using C + ED reconstructions. Readers 1 and 2 detected 6 and 9 of 18 hematomas on CCT, respectively. CCT showed a sensitivity of 33-50 % and a specificity of 75-80 %, while for C + ED reconstructed images the sensitivity was 77-83 % and the specificity was 85-90 %. Accuracy increased from 55-66 % to 84 % by using C + ED images. The minimum thickness for detecting hematoma on C + ED images was 3 mm. The sizes of prevertebral hematoma on CCT/C + ED were not significantly under- or overestimated compared to the MRI reference. There was a significant difference between the two readers for measuring hematoma sizes on CCT (p = 0.04). Readers showed an excellent inter-rater reliability (kappa = 0.82) for C + ED images and a moderative inter-rater reliability (kappa = 0.44) for CCT.

CONCLUSION

 With SDCT, the diagnostic accuracy for detecting post-traumatic prevertebral hematoma is improved by using combined conventional and electron density reconstructions compared to conventional images alone.

KEY POINTS

  · SDCT has a high potential for detecting post-traumatic prevertebral hematomas of the cervical spine by using combined conventional and electron density images.. · Prevertebral hematomas with a thickness of less than 3 mm cannot be reliably identified by SDCT.. · There is no discernible value of conventional SDCT images for diagnosing prevertebral hematoma..

CITATION FORMAT

· Sedaghat S, Langguth P, Larsen N et al. Diagnostic Accuracy of Dual-Layer Spectral CT Using Electron Density Images to Detect Post-Traumatic Prevertebral Hematoma of the Cervical Spine. Fortschr Röntgenstr 2021; DOI: 10.1055/a-1529-7010.

Accuracy of craniocervical measurements on CT for identifying partial or complete craniocervical ligament injuries in pediatric patients

PURPOSE

To assess the accuracy of craniocervical measurements for identifying craniocervical injuries and the frequency of subjective findings of craniocervical injuries on CT in pediatric patients.

METHODS

Case-controlled retrospective review of patients ≤ 16 years old with craniocervical junction injuries. Receiver operator curves were created for common craniocervical measurements on CT comparing patients with complete and partial craniocervical injuries to uninjured cohort. Frequency of subjective CT findings of craniocervical injury was assessed in the injured cohort.

RESULTS

For complete disruption injuries (CD) (n = 27), C1-C2 distance (AUC = 0.90, 95%CI = 0.83-0.97), atlanto-occipital distance (AUC = 0.95-0.98, 95%CI = 0.90-1.00), and basion-dens distance (AUC = 0.90, 95%CI = 0.82-0.98) had excellent accuracy diagnosing injury. Powers ratio (AUC = 0.85, 95%CI = 0.76-0.94) had good, basion-posterior axial line (AUC = 0.74, 95%CI = 0.61-0.86) fair, and atlanto-dental distance (AUC = 0.69, 95%CI = 0.57-0.82) poor accuracy. For partial disruption injuries (PD) (n = 21), basion-dens distance (AUC = 0.75, 95%CI = 0.62-0.88) had fair accuracy diagnosing injury. Powers ratio (AUC = 0.63, 95%CI = 0.47-0.79), C1-C2 distance (AUC = 0.60, 95%CI = 0.45-0.75), atlanto-dental distance (AUC = 0.55, 95%CI = 0.39 = 0.71), atlanto-occipital distance (AUC = 0.63-0.65, 95%CI = 0.47-0.81), and basion-posterior axial line (AUC = 0.60, 95%CI = 0.44-0.76) all had poor accuracy. Eighty-one percent (n = 22) of CD and 38% (n = 8) of PD patients had non-concentric atlanto-occipital joints. One hundred percent of CD patients had ≥ 1 soft tissue finding and eighty-one percent (n = 22) had ≥ 2 findings. Seventy-three percent (n = 16) of PD patients had ≥ 1 soft tissue finding. Eighty-six percent (n = 18) of PD patients had non-concentric atlanto-occipital joints and/or soft tissue findings.

CONCLUSION

Craniocervical measurements have poor accuracy for identifying craniocervical injuries in pediatric patients with incomplete craniocervical ligament disruption. Subjective findings of craniocervical injury are frequently present on CT in pediatric patients and can help increase sensitivity for identifying injury.

Imaging of pediatric cervical spine trauma

While pediatric cervical spine injuries (CSI) are rare, they are associated with high morbidity and mortality and sometimes require expeditious surgical management. In this article, we aim to improve the diagnostic accuracy of pediatric CSI by reviewing normal pediatric cervical anatomy, typical pediatric CSI patterns, and common mimics of pediatric CSI. A literature review was conducted on pediatric CSI, its epidemiology, and the various imaging manifestations and mimics. The most common pediatric CSI occur in the upper cervical spine owing to the higher fulcrum and larger head at a young age, namely prior to age 9 years, while lower CSI occur more frequently in patients older than 9 years. While various craniocervical measurements may be utilized to identify craniocervical disruption, soft tissue injuries may be the only manifestation, thus making pediatric CSI difficult to diagnose on initial imaging. In the acute setting, CT cervical spine is an appropriate initial imaging modality for pediatric CSI evaluation. MRI serves as an additional tool to exclude or identify injuries when initial findings are equivocal. It is essential to recognize the unique anatomy and biomechanics of the pediatric spine and thus discern common pediatric CSI patterns and their mimics.

Management of cervical spine trauma in children

PURPOSE

Paediatric cervical spine injuries are fortunately a rare entity. However, they do have the potential for devastating neurological sequelae with lifelong impact on the patient and their family. Thus, management ought to be exceptional from the initial evaluation at the scene of the injury, through to definitive management and rehabilitation.

METHODS

We set out to review cervical spine injuries in children and advise on current best practice with regards to management.

RESULTS

Epidemiology, initial management at the scene of injury, radiological findings and pitfalls of cervical spine trauma are outlined. Strategies for conservative and surgical management are detailed depending on the pattern of injury. The management of spinal cord injuries without radiological abnormality (SCIWORA) and cranio-cervical arterial injuries is also reviewed.

CONCLUSIONS

Due to a paucity of evidence in these rare conditions, expert opinion is necessary to guide best practice management and to ensure the best chance of a good outcome for the injured child.

Tailored Posterior Pharyngeal Fat Grafting Outcomes in Velopharyngeal Insufficiency Managed According to a Simplified Algorithm

BACKGROUND

This study aimed to evaluate the outcomes of posterior pharyngeal fat grafting for the management of velopharyngeal insufficiency using a simplified therapeutic algorithm and a tailored surgical technique.

METHODS

This was a prospective study of consecutive nonsyndromic patients with repaired cleft palate and velopharyngeal insufficiency who were stratified according to a simplified algorithm (minimally scarred palate, transverse orientation of levator veli palatini, and pinhole-to-small velopharyngeal gaps) and who underwent tailored posterior pharyngeal fat grafting. The patients were screened for obstructive sleep apnea before and after surgery. Three blinded evaluators randomly rated perceptual speech (hypernasality, audible nasal emission, and intraoral pressure) and nasoendoscopic (velopharyngeal active gap size) characteristics using audio and video recordings. Successful speech outcome was defined as normal or borderline sufficient velopharyngeal function at 15 months after surgery.

RESULTS

All included patients (n = 96) presented with a preoperative and postoperative low risk of obstructive sleep apnea. At 15 months after surgery, hypernasality (0.26 ± 0.53), audible nasal emissions (0.29 ± 0.48), intraoral pressure (0.1 ± 0.31), and velopharyngeal closure size (1.86 ± 0.34) were significantly decreased (all, P < 0.05) compared with the corresponding preoperative measurements (hypernasality, 2.17 ± 0.75; audible nasal emissions, 1.89 ± 0.82; intraoral pressure, 0.85 ± 0.35; and velopharyngeal closure size, 0.2 ± 0.49). In total, 84 (87.5%) patients showed successful speech outcomes.

CONCLUSIONS

Tailored posterior pharyngeal fat grafting is an effective and safe surgical strategy for the management of velopharyngeal insufficiency in a selected cohort of patients with repaired cleft palate.

Measurements in cervical vertebrae CT of pediatric cases: normal values

PURPOSE

This study aims to determine the normal limits of atlanto-dental interval (ADI), basion-dens interval (BDI), basion-cartilaginous dens interval (BCDI), and prevertebral soft tissue thickness (PVSTT) according to age groups for normal pediatric cases.

MATERIALS AND METHODS

CT images of 256 pediatric patients aged between 1 and 15 years were retrospectively evaluated. ADI, BDI, BCDI and PVSTT measurements were performed.

RESULTS

Upper normal limit (UNL) values for ADI were 2.65-4.8 mm. UNL values for PVSTT were found to be 6.9 mm at C1 level, 6.7 mm at C2 level, 9.3 mm at C3 level, 14.2 mm at C4 level, 14.1 mm at C5 level, 13.8 mm at C6 level and 12.8 mm at C7 level. The maximum value of BDI in the group with non-ossified os terminale was 12 mm, and in the group with ossified os terminale it was 10 mm. The UNL of BCDI determined for females was 5.1 mm, while the UNL for males was 5.6 mm.

CONCLUSION

We propose the obtained values as the UNL values for ADI, BDI, BCDI and PVSTT on CT images in the pediatric population from 1 to 15 years.

Delayed diagnosis of fractured anterior arch of the atlas in a young child

A 2-year-old girl fell off a bunk bed onto a parquet floor. She immediately reported neck pain and presented with muscle spasm and limited motion of the cervical spine (C-spine). Plain X-rays of the C-spine showed no osseous lesion. Owing to persisting pain and limited motion in the neck, MRI of the C-spine was obtained which revealed intact ligaments and cervical spinal cord, as well as soft tissue swelling in front of the anterior arch of the atlas. Subsequent CT of the C-spine confirmed a complete, undisplaced fracture of the anterior arch of the atlas (Gehweiler type I fracture). A Minerva cast was applied for 2 months, followed by a soft cervical collar. Persistent neck pain and limited range of motion of the neck after a fall may be indicative of atlas fracture that should be ruled out by CT.

Magnetic Resonance Imaging of Pediatric Neurologic Emergencies

Although computed tomography is often the first line of imaging in the emergency setting, magnetic resonance imaging (MRI) is of increasing importance in the evaluation of central nervous system emergencies in the pediatric population. As such, it is necessary to understand the indications for which MRI may be necessary. This article reviews the unique pathophysiologic entities affecting the pediatric population and the associated MRI findings. Specifically, utility of emergent MRI and characteristic appearances of traumatic brain injury, traumatic spinal injury, nonaccidental trauma, arterial ischemic stroke, cerebral sinovenous thrombosis, stroke mimics, and central nervous system infections are described.