Predicting complications of pediatric temporal bone fractures

Temporal Bone Fractures and Related Complications in Pediatric and Adult Cranio-Facial Trauma: A Comparison of MDCT Findings in the Acute Emergency Setting

PURPOSE

The purpose of this study was to analyze the prevalence of and complications resulting from temporal bone fractures in adult and pediatric patients evaluated for cranio-facial trauma in an emergency setting.

METHODS

A retrospective blinded analysis of CT scans of a series of 294 consecutive adult and pediatric patients with cranio-facial trauma investigated in the emergency setting was conducted. Findings were compared between the two populations. Preliminary reports made by on-call residents were compared with the retrospective analysis, which was performed in consensus by two experienced readers and served as reference standard.

RESULTS

CT revealed 126 fractures in 116/294 (39.5%) patients, although fractures were clinically suspected only in 70/294 (23.8%); p < 0.05. Fractures were longitudinal, transverse and mixed in 69.5%, 10.3% and 19.8% of cases, respectively. Most fractures were otic-sparing fractures (95.2%). Involvement of the external auditory canal, ossicular chain and the osseous structures surrounding the facial nerve was present in 72.2%, 8.7% and 6.3% of cases, respectively. Temporal bone fractures extended into the venous sinuses/jugular foramen and carotid canal in 18.3% and 17.5% of cases, respectively. Vascular injuries (carotid dissection and venous thrombosis) were more common in children than in adults (13.6% versus 5.3%); however, the observed difference did not reach statistical significance. 79.5% of patients with temporal bone fractures had both brain injuries and fractures of the facial bones and cranial vault. Brain injuries were more common in adults (90.4%) than in children (63.6%), p = 0.001. Although on-call residents reliably detected temporal bone fractures (sensitivity = 92.8%), they often missed trauma-associated ossicular dislocation (sensitivity = 27.3%).

CONCLUSIONS

Temporal bone fractures and related complications are common in patients with cranio-facial trauma and need to be thoroughly looked for; the pattern of associated injuries is slightly different in children and in adults.

Complications After Pediatric Temporal Bone Fractures by Classification System: A Systematic Review and Meta-analysis

OBJECTIVE

To analyze the rates of complications after pediatric temporal bone fractures (TBF) and the utility of the longitudinal, transverse, and mixed versus the otic capsule sparing (OCS) and otic capsule violating (OCV) classification systems in predicting these complications.

DATA SOURCES

PubMed, Scopus, and CINAHL.

REVIEW METHODS

Per PRISMA guidelines, studies of children with TBFs were included. Meta-analyses of proportions were performed.

RESULTS

A total of 22 studies with 1376 TBFs were included. Children with TBF had higher rates of conductive hearing loss (CHL) than sensorineural hearing loss (SNHL) (31.3% [95% confidence interval [CI] 23.2-40.1] vs 12.9% [95% CI 8.9-17.5]). No differences in both CHL and SNHL were seen between longitudinal and transverse TBFs; however, OCV TBFs had higher rates of SNHL than OCS TBFs (59.3% [95% CI 27.8-87.0] vs 4.9% [95% CI 1.5-10.1]). Of all patients, 9.9% [95% CI 7.2-13.1] experienced facial nerve (FN) paresis/paralysis, and 13.4% [95% CI 5.9-23.2] experienced cerebrospinal fluid otorrhea. Transverse TBFs had higher rates of FN paresis/paralysis than longitudinal (27.7% [95% CI 17.4-40.0] vs 8.6% [95% CI 5.2-12.8]), but rates were similar between OCS and OCV TBFs.

CONCLUSION

CHL was the most common complication after TBF in children; however, neither classification system was superior in identifying CHL. The traditional system was more effective at identifying FN injuries, and the new system was more robust at identifying SNHL. While these results suggest that both classification systems might have utility in evaluating pediatric TBFs, these analyses were limited by sample size. Future research on outcomes of pediatric TBFs stratified by type of fracture, mainly focusing on long-term outcomes, is needed.

Vascular injury arising from lateral skull base fractures

PURPOSE

Although uncommon, vascular injury can be seen in patients with lateral skull base fractures (LSBF). However, little is known about this potentially life-threatening comorbidity. The objective of this study is to better characterize the vascular injuries associated with temporal and lateral sphenoid bone fractures.

BASIC PROCEDURES

Retrospective review of all patients with computed tomography angiography (CTA) performed specifically to evaluate for vascular injury following LSBF. In addition to patient demographics (age, gender, race), the mechanism of injury, the location of fracture(s), and the nature of vascular injury diagnosed by CTA was recorded. Two-way ANOVA was performed to determine if any variables were predictive of vascular injury.

MAIN FINDINGS

From 2011 to 2021, 143 patients with 333 subsite fractures met inclusion criteria. Of all patients, 46 (32.2 %) had CTA evidence of at least one vascular injury, the most common type being venous thrombosis/filling defect (41.7 %). Evidence of vascular injury was unclear in 14 patients (9.8 %). Fractures most associated with vascular injury ranged from 0.7 % (otic capsule fractures) to 26.7 % (mastoid, lateral sphenoid fractures). Risk of vascular injury was no different between patients with single vs multiple fractures. There were no fracture locations that could reliably predict specific vascular injury.

CONCLUSIONS

Over 40 % of all CTAs ordered following LSBF identified were suspicious for associated vascular injury. Yet fracture location and number cannot reliably predict vascular injury. Until such determinants can be better identified, clinicians should have a low threshold to obtain CTA to rule out associated vascular injury.

Utilization of computed tomography in pediatric temporal fractures: A dose reduction approach

OBJECTIVES

METHODS: Retrospective chart review was performed of pediatric patients who underwent CT brain as part of a trauma pan-scan and dedicated temporal bone CT in the setting of head trauma. The original CT images were re-reviewed by two board certified Neuroradiologists in a blinded manner to determine the presence or absence of temporal bone fracture and if present, fracture line involvement of the 5 critical temporal bone anatomic structures. The dose length product (DLP), a measure of approximate total radiation dose delivered during CT scan (mGy-cm), was noted from the data available.

RESULTS

There were 24 temporal bone fractures in a total of 29 patients (4 with bilateral fractures). There were 21 of 24 fractures that were correctly identified on trauma pan-scan CT with dedicated temporal bone CT considered as the diagnostic gold standard. There was a combined sensitivity and specificity of 91 % and 100 % respectively. The sensitivity and specificity in identifying involvement of critical structures were as follows: carotid canal (100 % and 100 %); ossicular chain (75 % and 100 %); tegmen tympani (60 % and 97.9 %); facial nerve canal (25 % and 100 %); otic capsule (N/A and 98.5 %). The median DLP for trauma pan-scan CT and temporal bone CT were 627 mGy-cm and 267 mGy-cm respectively.

CONCLUSION

Dedicated TBCT is not required to accurately diagnose and characterize temporal bone fractures seen on trauma pan-scan CT. The radiation exposure of concurrent or subsequent dedicated temporal bone imaging is equal to approximately one half of the original trauma pan-scan CT.

Otologic injuries are frequent in pediatric patients with temporal bone fractures

This retrospective study aimed to clarify the occurrence and types of otologic injuries in children and adolescents with skull fractures. Files of all patients under 18 years of age who had been diagnosed with skull fractures at a tertiary trauma centre were included. The primary outcome variable was the presence of any otologic symptom or finding. Secondary outcome variables were clinically detected and radiologically detected otologic injuries. The primary predictor variable was a temporal bone fracture. Other study variables were sex, age, mechanism of injury, traumatic brain injury, and mortality. A total of 97 patients were identified for the study. Otologic symptoms and findings were frequent (33.9%). The most common clinical findings were bleeding from the external auditory canal (18.6%) and hemotympanum (13.4%). The prevailing radiological finding was blood and/or cerebrospinal fluid in the middle ear (30.9%). Patients with fractures of temporal bone had a 29-fold risk for otologic symptoms or findings (RR 28.9, 95% CI 4.1-202.9, p < 0.001) relative to those who did not have a temporal bone fracture. Severe otologic complications, such as permanent hearing loss (6.2%), cerebrospinal fluid leak (5.2%), or facial nerve palsy (1%), were infrequent. Within the limitations of the study it seems that there is the necessity of otoscopy in all pediatric patients with blunt head trauma. In case of positive otologic findings, the patient should undergo imaging and ENT consultation.