Linear fractures invisible on routine axial computed tomography: a pitfall at radiological screening for minor head injury

Head Injury during Childbirth

Head injuries are the most common type of birth injuries. Among them, most of the injuries is limited to the scalp. and the prognosis is good enough to be unnoticed in some cases. Intracranial injuries caused by excessive forces during delivery are rare. However, since some of them can be fatal, it is necessary to suspect it at an early stage and evaluate thoroughly if there are abnormal findings in the patient.

Cranial Suture Evaluation in Pediatric Head Trauma: Importance in Differentiating Abusive From Accidental Injury

OBJECTIVES

Pediatric skull fracture association with the cranial sutures (crossing, widening, or contacting 2 or more cranial sutures) is suggestive of abusive injury. We studied the efficacy of head computed tomography (CT) versus skull radiographs in identifying pediatric skull fracture association with cranial sutures and reviewed head CT literature recommendations for pediatric head trauma.

METHODS

Retrospective review was performed of skull radiographs and head CT at a tertiary care, free-standing children's hospital (2012-2019). Statistical 2-proportion Z test determined efficacy of head CT versus skull radiographs in assessing cranial suture involvement with fractures.

RESULTS

Forty-seven children with 56 abusive skull fractures and 47 children with 54 accidental skull fractures were evaluated, ages 1 to 36 months. Of the 110 total skull fractures evaluated, 51 abusive and 41 accidental skull fractures had terminal ends contacting cranial sutures for a total of 92 (84%). Twelve abusive fractures (24%) crossed sutures; no accidental fractures crossed sutures (P < 0.01). Of the 12 abusive cases with skull fractures that crossed sutures, 7 were definitively identified only on CT (P < 0.01). Widened sutures were documented in 4 (8%) of the abusive cases with skull fracture; none in the accidental cases. All 4 of these cases were equally identified on both skull radiography and CT imaging. In 21 of 47 abusive versus 5 of 47 accidental cases, CT identified skull fractures lines that extended to cranial sutures that were not definitive on skull radiography (P = 0.00022).

CONCLUSIONS

Cranial suture involvement with pediatric skull fractures is common. Head CT significantly aided in the identification of skull fractures contacting and crossing cranial sutures in abusive cases, supporting eliminating concurrent skull radiographs.

Identification and management of neonatal skull fractures

OBJECTIVE

Suspected skull fractures in the neonate are uncommon and present a management dilemma. We hypothesized that skull fractures are more common than reported in the literature and that few infants require any intervention.

STUDY DESIGN

We retrospectively reviewed the charts of 21 infants referred to our level IV Neonatal Intensive Care Unit for possible skull fracture over a 3-year period after birth trauma, suspicious findings on clinical exam, or accidental falls in the birth hospital.

RESULTS

Skull films at the birth hospital were unreliable for fracture in 23% of cases. Seven of nine infants with accidental falls had fracture on computed tomography scan. Only three infants required neurosurgical intervention, all after severe birth trauma associated with instrumentation.

CONCLUSION

Skull fractures are more common than previously reported in neonates after accidental falls, but few infants with skull fractures require neurosurgical intervention.

Routine Head Computed Tomography for Patients in the Emergency Room with Trauma Requires Both Thick- and Thin-Slice Images

Background. Images of head CT for the supratentorial compartment are sometimes recommended to be reconstructed with a thickness of 8–10 mm to achieve lesion conspicuity. However, additional images of a thin slice may not be routinely provided for patients with trauma in the emergency room (ER). We investigated the diagnostic sensitivity of a head CT, where axial images were 10 mm thick slices, in cases of linear skull fractures. Methods. Two trauma surgeons retrospectively reviewed head CT with 10 mm slices and skull X-rays of patients admitted to the ER that were diagnosed with a linear skull fracture. All patients had undergone both head CT and skull X-rays (n = 410). Result. The diagnostic sensitivity of head CT with a thickness of sequential 10 mm was 89% for all linear skull fractures but only 56% for horizontal fractures. This CT technique with 10 mm slices missed 6% of patients with linear skull fractures. False-negative diagnoses were significantly more frequent for older (≥55 years) than for young (<15 years) individuals (p = 0.048). Conclusions. A routine head CT of the supratentorial region for patients in the ER with head injuries requires both thick-slice images to visualize cerebral hemispheres and thin-slice images to detect skull fractures of the cranial vault.

Sensitivity and specificity of CT scan in revealing skull fracture in medico-legal head injury victims

BACKGROUND

Emergency departments rely on CT scans to manage trauma victims, especially for head injuries. Although the detection of an undisplaced fracture on a CT scan of the head without significant intracranial findings may be insignificant for a clinician, such cases are of paramount importance for medico-legal purposes because they help ascertain the nature, manner, and cause of the head injury.

AIMS

The study was conducted with the objective of knowing the sensitivity and specificity of ante-mortem CT scan findings indicating the presence or absence of skull fractures.

METHODS

Findings were confirmed during post-mortem examination of the subjects who had died during management but who had not had any surgical intervention. A comparative study of ante-mortem CT scan and autopsy findings with respect to fracture in traumatic head injuries was undertaken on 60 deceased individuals brought in for medico-legal post-mortem examination over a period of two years.

RESULTS

Considering the autopsy findings as the gold standard, we have concluded that 14.6 per cent of the fractures were missed on CT scan findings compared to fractures found during autopsy. The sensitivity of CT scan for skull fractures was found to be 85.4 per cent and specificity was 100 per cent. Kappa was 0.787, which shows good agreement with p<0.001, which was highly significant.

CONCLUSION

In developing countries, images are interpreted in the axial plane only on a CT scan of the head, which may be due to a lack of financial and human resources. For better delineation of fractures, the use of techniques like multi-detector CT with sagittal and coronal reformations should be considered in the routine interpretation of a CT scan of the head.