Childs Nerv Syst (2012) 28:1063–1068 DOI 10.1007/s00381-012-1717-9

ORIGINAL PAPER

Brain CT scan for pediatric minor accidental head injury. An Italian experience and review of literature C. Fundarò & M. Caldarelli & S. Monaco & F. Cota & V. Giorgio & S. Filoni & C. Di Rocco & R. Onesimo

Received: 24 November 2011 / Accepted: 1 February 2012 / Published online: 15 February 2012 # Springer-Verlag 2012

Abstract Purpose Every year 300,000 children with accidental head trauma are admitted to Italian emergency departments. Our aims were: (1) to describe patients with minor traumatic brain injury who were admitted to pediatric departments and underwent CT, and (2) to analyze the appropriateness of management according to current guidelines. Methods We retrospectively analyzed patients with minor head injury (median age 4.5 years, range 1 month to 16 years) who were admitted to the pediatric department of the Catholic Medical School of Rome, from January 2005 to September 2010, who performed head CT. Univariate analysis was performed using the Fisher’s exact test. Multivariate analysis was performed by logistic regression. Results One hundred and seventy-four patients were enrolled in the study. Fifty-four patients (31%) had pathological CT findings. Eight patients underwent neurosurgical treatments. Vomiting was the only symptom significantly prevalent in the infant group, compared to the children group (10.7% vs. 38.9%, p00.007), while loss of consciousness in the children group (50.0% vs. 25.0%, p00.040). The

C. Fundarò : S. Monaco : F. Cota : V. Giorgio : S. Filoni : R. Onesimo Department of Pediatrics, Catholic University of Rome, Rome, Italy M. Caldarelli : C. Di Rocco Department of Neurosurgery, Catholic University of Rome, Rome, Italy R. Onesimo (*) Department of Pediatrics, Catholic University of Sacred Heart, L. go Gemelli 8, 00168 Rome, Italy e-mail: [email protected]

relationship between scalp swelling and CT abnormalities was statistically significant in the entire population. The incidence of head abnormalities was significantly higher in children with abnormal CT (92.6% vs. 72.5%). Conclusions The best way to manage children with minor head trauma is still matter of debate. Loss of consciousness and scalp swelling are risk factors predicting brain injury that deserve CT control. The radiation risks posed by CT scanning in children must be balanced by the benefits. We believe that even though CT scans may be clinically unnecessary in many cases, the rate of scanning is justified by the even limited number of abnormalities which require neurosurgical treatment. Keywords Head injury . Brain CT scan . Head injury guidelines . Childhood

Introduction Traumatic brain injury (TBI) is the first cause of death in pediatric age and causes significant morbidity among survivors [1]. Every year over 400,000 children in the USA apply to an emergency department (ED) because of an accidental head trauma, resulting in 30,000 hospitalizations [2]. Data about brain injury collected in Europe are even more alarming, probably due to the differences in the National Health System policy and the following bigger facilities to access the ED. As a matter of fact, data collected in the UK show that approximately 350,000 children every year are admitted to the ED [3] for head injury, and this is in line with what is estimated in Italy, where around 300,000 pediatric patients per year attend the ED [4]. Children with brain injury who require neurosurgical treatment should be quickly identified. Computed tomography

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(CT) of the head is the gold standard for the diagnosis of complications from TBI. There are different guidelines [3, 5–7] available for the management of TBI and variable CT indications, and few of them validated for the pediatric population are about minor head injury [7–10]. In Italy, few clinical studies about pediatric head trauma have been documented [4]. Moreover, pediatric epidemiological data are often incomplete. The primary aim of this study was to describe patients with minor TBI who were admitted for hospitalization to an Italian university pediatric department and underwent CT. The secondary aim was to analyze the appropriateness of management of children’s TBI according to the current guidelines.

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regression in order to define the role of specific factors that may be related to the cranial CT abnormality. All the variables considered were entered into the initial model. Backward stepwise selection was used to select the variables to enter in the final model with a significance level for the removal and the addition respectively of 0.3 and 0.2. The goodness of fit of the logistic regression models was checked by the Hosmer and and Lemeshow's goodness-of-fit test. A two-tailed value of p<0.05 was considered significant. Statistical analysis was performed using the “Stata Statistical Software: Release 11” (StataCorp LP, College Station, TX).

Results Materials and methods The clinical notes of all patients with minor head injury who were admitted for observation to the pediatric department of the Catholic University Medical School of Rome, and performed head CT from January 2005 to September 2010, were retrospectively analyzed. We excluded patients (1) elder than 16 years, (2) with moderate or severe head injury, (3) with no clear history of trauma as primary event (i.e., primary seizure), (4) who returned for reassessment of the same head injury, and (5) were involved in road accidents. Clinical data, including age, gender, symptoms at first evaluation, physical examination findings, radiological investigation results, and the length of stay, were collected. Data were filed using Microsoft Excel. The choice to perform head CT scans was taken on the basis of various clinical decision rules for assessing head injuries (Children’s Head injury Algorithm for the Prediction of Important Clinical Events—CHALICE [9] and Pediatric Emergency Care Applied Research Network— PECARN [11]) published to help in the diagnosis and reduce the need for head CT scans. We have also followed the latest international guidelines about the management of TBI and CT indications, Scottish Intercollegiate Guidelines Network (SIGN) [7], and the Italian Society of Anesthesia, Resuscitation and Intensive Care (SIIARTI) [8]. Head CT scans were examined by local radiologists and pediatric neurosurgeons and were considered positive for TBI if they showed any pathological finding (skull fracture, subdural, epidural, subarachnoid bleeding) not attributable to events other than trauma. Criteria for deciding surgery were discussed by neurosurgeons on the bases of the CT scan results (depressed fractures or subdural hematomas). The analysis was performed on the whole population and then on two age-related subgroups (<2 and ≥2 years). Univariate analysis was performed using the Fisher’s exact test. Multivariate analysis was performed by logistic

A total of 174 patients with minor head trauma underwent CT scan and were hospitalized in the pediatric department of Catholic University Medical School of Rome, from January 2005 to September 2010. One hundred twenty-five (72%) children presented with local signs of trauma upon physical examination of the head (the most frequent was parietal swelling); concussive head injury occurred in 47 children (27%), but none presented with loss of consciousness >1 min, 40 (23%) presented three or more episodes of vomiting, and 3 (1.7%) had seizures. One hundred patients (57%) were in the infant group (under 2 years of age) of whom 38% had <1 year, and 74 (43%) were in the children group (above 2 years of age). Males were 119 (68%) of the entire population. The mean observation time was 3 days. Data about clinical and demographic features of children are reported in Table 1. The comparison between clinical signs and symptoms and CT findings is summarized in Tables 2 and 3. Thirty-eight patients (22%) underwent repeated cranial CT, for a total of 214 radiological examinations. Fifty-four patients (31%) had pathological CT findings (66% skull fracture, 14% subdural hematoma, 20% epidural hematoma). One hundred twenty patients (69%) had normal CT; they received cranial CT because of the presence of at least one of the criteria for CT suggested by SIGN guide lines (23 loss of consciousness, 23 one or more episodes of vomiting, 21 children under 1 year, 53 children with clinical signs suggestive for skull fracture). Eight patients (4.6%; three in the infant group and five in the children group) underwent neurosurgical treatment. CT scan revealed skull depressed fracture in all cases. Concussive head injury occurred in five of them (63%). All of them had a length of stay above 72 h (range 24 h to 1 month). Demographic features and clinical, radiological, and surgical data of these patients are shown in Table 4. Loss of consciousness and vomiting were the symptoms which significantly differed between the pathologic and normal CT groups in the population (loss of consciousness 35.2% vs. 20%, respectively, p 00.038; vomit 13% vs.

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Table 1 Data about demographic, clinical, and physical features Number

%

Male Female

119 55

68 32

Age <2 years

100

57

74 45

43 26

Nonconcussive trauma

129

74

Neurosurgery Observation time >48 h

8 56

4 32

Age >2 years Concussive trauma

Signs

147

84

Lacerated and contused wound Head swelling

31 77

18 44

Hematoma

24

14

Ecchymosis Fracture

9 6

5 3

Symptoms

118

68

Vomiting Headache

52 7

30 4

Loss of consciousness Hyporeactivity

43 16

25 9

did not differ between the normal and abnormal CT groups in the total population and in the age subgroups either. Scalp swelling and CT abnormalities were significantly correlated in the population (61.1% vs. 36.7%, respectively, p00.003) and in the infant group (67.9% vs. 34.7%, p00.004). The presence of at least one of following signs (head swelling, contused lacerated injury, hematoma, ecchymosed, depressed skull fracture) was significantly different between the normal and abnormal CT groups in the total population (92.6% vs. 72.5%, p00.002); it was confirmed in the infant group (96.4% vs. 70.8%, p00.006), and not in the children group. The results of the multivariate analysis are shown in Table 3.

Discussion According to the American Academy of Pediatrics, mild TBI is identified in patients who have normal mental status at the initial examination, who have no abnormal or focal neurological findings, and who have no physical evidence of skull fractures. This definition of mild head injury correlates with a Glasgow Coma Scale (GCS) score of 13 or above [12]. Accidental falls are the main cause of TBI in infants, while road accidents and sport-related injuries are predominant in children >1 year old [13]. In our country the incidence of pediatric head trauma in 1999 was 271.6/100,000 inhabitants. The highest incidence was recorded among male infants (739.1 events /100,000 abs) [14]. In our study we found that boys had higher rates of TBI than girls in each age subgroup, according to other studies [15–18]. It can be explained by greater male risk-taking

37.5%, respectively, p00.001). The prevalence of vomiting was the only symptom significantly prevalent in the infant group, compared to the children group (10.7% children group vs. 38.9% infant group, p00.007), while loss of consciousness was significantly prevalent in the children group (50.0% children group vs. 25.0% infant group, p00.040). The presence of at least one of the following symptoms (vomiting, headache, loss of consciousness, hyper reactivity) Table 2 The comparison of clinical signs and symptoms with CT findings

Univariate analysis of the population

Normal CT scan (n0120)

Pathological CT scan (n054)

n

N

%

p

%

Male

79

6.8

40

74.1

0.297

<2 years Concussive head injury Lacerated and contused wound Head swelling Hematoma Ecchymosis Fracture Vomiting Headache Loss of consciousness Hyporeactivity Total signs Total symptoms

72 26 24 44 16 9 4 45 5 24 11 87 78

60.0 21.7 2.0 36.7 13.3 7.5 3.3 37.5 4.2 20.0 9.2 7.5 65.0

28 19 7 33 8 0 2 7 2 19 5 50 33

51.9 35.2 13.0 61.1 14.8 0.0 3.7 13.0 3.7 35.2 9.3 92.6 61.1

0.325 0.064 0.293 0.003 0.814 0.059 1.000 0.001 1.000 0.038 1.000 0.002 0.73

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Table 3 Comparison of clinical signs and symptoms with CT findings

Multivariate analysis of the population [odds ratio (OR), 95% confidence of interval (CI)] a

Significant at 5%

b

Significant at 1%

Model

Total [OR (CI)]

Vomiting Lenght of stay

0.333 (0.129–0.859)a 0.157 (0.227–1.179)

Loss of consciousness Fracture

1.722 (0.761–3.894) 3.708 (0.485–28.371)

Head swelling Hematoma

3.424 (1.539–7.619)b 2.631 (0.872–7.940)

Gender Log likelihood Pseudo R2 Observation

−90.677989 0.1206 162

behaviors and differences in male socialization. There is a wide consensus about the management of children with moderate or severe head trauma (i.e., GCS <13 at assessment in emergency department, witnessed loss of consciousness >5 min, suspicion of open or depressed skull fracture or tense fontanel, focal neurological deficit, any sign of basal skull fracture) [7–9], while the management of children with apparently minor head trauma is still debated. In 2009, the SIGN [7] has worded the guide lines for the management of minor pediatric head trauma; according to these guidelines, an immediate CT should be performed on children with witnessed loss of consciousness >5 min, GCS <13, focal neurological deficit, suspected open or depressed skull injury or tense fontanel, and any sign of basal skull fracture. A CT should be performed within 8 h in the presence of a large hematoma (5 cm), posttraumatic seizure, a significant fall, three or more episodes of vomit, somnolence, and serious road accident. If CT is negative on admission, a new control is recommended in the presence of neurological clinical variations; if CT is abnormal on admission, it is

<2 years [OR (CI)]

>2 years [OR (CI)]

0.19 (0.048–0.749)a 0.237 (0.045–1.238) 3.999 (1.263–12.661)a 8.434 (0.800–88.948) 6.81 (1.921–24.136)b 2.651 (0.557–12.615) −46.986973 0.1689 92

3.579 (0.602–21.280) 2.062 (0.548–7.753) −39.713945 0.1312 69

generally advisable to repeat a second exam after 6 h if the first examination was performed soon after trauma (within 6 h). Otherwise, repeat CT scan after 12 h. The same recommendations can be found in the guidelines of the SIIARTI [8]. In our clinical practice, as suggested by Tufano and Di Rocco [19], we followed these guidelines, particularly useful since they were developed in Italy and reflect the experience of the country’s major trauma centers. Despite the formulation of clinical decision rules, less than 10% of CT scans in children with minor head trauma show TBI [20]. Therefore the accuracy and predictive value of rules which could identify children at very low risk of TBI should be revised. Early identification of factors predicting abnormal cranial CT scans is important for quality assessment and could contribute to the more effective management of TBI in children. Several studies have been performed in the past to identify risk factor for TBI [20, 21]. For example the CHALICE rule [9] has suggested some variables included in the decision rules for identifying pediatric patients with minor

Table 4 Clinical, radiological and surgical features of patients who underwent neurosurgical treatment Gender

Age (months)

CT scan indication

CT scan result

Neurosurgical intervention

F

4

Head swelling, vomiting

M

16

Parietal craniotomy, hematoma evacuation Parietal minicraniotomy

M M

48 6

Temporal fracture, hematoma Subdural fracture, hematoma

M

30

Loss of consciousness, head swelling Head swelling Loss of consciousness, head swelling Head swelling

Parietal fracture, epidural hematoma Parietal fracture

M

27

M

72

M

26

Temporal minicraniotomy Temporal craniotomy, hematoma evacuation Parietal craniotomy, hematoma evacuation Temporal craniotomy, hematoma evacuation Parietal craniotomy, hematoma evacuation Temporal craniotomy, hematoma evacuation

Loss of consciousness, head swelling Loss of consciousness, head swelling Loss of consciousness, head swelling

Parietal fracture, hematoma Temporal fracture, hematoma Parietal fracture, hematoma Temporal fracture, hematoma

PECARN

CHALICE

+

+

+

+

+ +

+ +

+

+

+

+

+

+

+

+

PECARN Pediatric Emergency Care Applied Research Network [11], CHALICE Children’s Head injury Algorithm for the Prediction of Important Clinical Events [9]

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head injury such as abnormal mental status, clinical signs of skull fracture, vomiting, neurological deficit, scalp trauma, loss of consciousness, amnesia, and seizure; some of these variables are considered by PECARN rule [11] (abnormal mental status, clinical signs of skull fracture, neurological deficit, scalp trauma, loss of consciousness), while vomiting, amnesia, and seizure are not present. Recent studies [9, 15, 22–24] have demonstrated that local pathological findings upon physical examination of the head (scalp swelling, fracture or contused lacerated injury) represent statistically significant predictors of pathological CTs. Our study confirms that scalp swelling and loss of consciousness were risk factors, as significantly correlated with abnormal cranial CT. Some studies suggest an increased risk of intracranial injury in the presence of a skull fracture; on the other hand, Kumar et al. [25] did not confirm the observation of increased intracranial injuries associated with linear fractures in the presence of normal GCS. Our study demonstrated that loss of consciousness was associated with an increased risk of abnormal CT for children above 2 years. The significance of loss of consciousness in children after head injury is still debated, because most authors have found that a prolonged loss of consciousness (>5 min) is associated with a high risk of intracranial lesion [11, 26]. Conflicting results exist for shorter durations, partly because this symptom is often difficult to ascertain, especially in younger children [4, 24, 26, 27]. Moreover, some authors believe that very short loss of consciousness (less than 5 min) may be the consequence of vagal reactions to pain and may not necessarily imply that an intracranial damage has occurred [4]. Despite this in our study, 10.6% of children who presented loss of consciousness of <1 min underwent neurosurgical treatment. Vomiting was found in 30% of our population, according to other studies [15, 20]. Our work showed that vomiting is predominant in the younger age group, in line with previous publications, where it was suggested that younger children vomit more easily after minor head injuries compared to elder children and adults [15, 28]. Most authors would agree that vomiting does not necessarily imply a more severe head trauma or TBI, but its significance remains unclear [29]. In our study, in fact, we found that vomiting was significantly more frequent in children with normal CT scan and of the age group of <2 years (p<0.05). Other reports in the literature [28–30] suggest that there are intrinsic factors predisposing some individuals to vomit after head injury. These include family history of migraine and a personal history of migraine, or its childhood variants, or associated conditions such as motion sickness. Moreover data coming from Turkey published in 2009 by Guzell et al. [15] showed that in 139 out of 916 children undergoing CT scan for head injury, vomit was present in 17% of children with positive CT scan vs.

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45.2% with negative CT scan (p<0.01), being significantly prevalent in those patients with no pathologies at the CT scan, very similarly to what was observed in our study. This can be explained because most of these patients reported occipital trauma, which is more frequently associated with vomiting. It has been postulated that blows to the occipital region potentially stimulate a central emetic center thought to reside in the reticular formation of the lateral medulla [29, 31]. It is difficult to provide scientific hypothesis to explain this result, as vomiting can also be easily related to a vagal reaction to the HT or can be a consequence of the pain, especially in children less than 2 years of age. But the role of trauma to a central emetic center should be more clearly defined. Cranial CT is the gold standard for diagnosis of TBI. Many TBI identified by CT do not need urgent treatment or any treatment. Among children with minor head injury, about 50% usually undergo CT but less than 10% show evidence of cranial or brain damage. In our study 174 children (58%) received CT scan, 54 of them (31%) had pathological CT findings. Furthermore, injuries needing neurosurgical treatment are very uncommon in children with GCS scores of 14–15 [22]. Martin et al. [10] found that only 0.6% of children with TBI needed neurosurgical intervention; a similar percentage (1.5%) was found by Guzel and coworkers [15]. In the present study, we found that 4.6% of patients needed neurosurgical intervention. Cautious utilization of CT use is important because ionizing radiation from CT scans can cause lethal malignancies. Moreover the test often requires pharmacological sedation, which causes further risks to the patients [32, 33]. The estimated rate of lethal malignancies form CT is between 1 in 1,000 and 1 in 5,000 pediatric cranial CT scans, with risks that increase as age decreases [32]. In a recent report by Mazonakis et al. [34], the authors demonstrated that the predicted scatter from a head CT would result in thyroid malignancy in 4 to 65 children per million scans. In our study 100% of patients underwent CT according to CHALICE [9], SIGN, and SIIARTI guidelines [7, 8]; 69% of them had a normal CT scan result. If we followed PECARN guidelines [11], we could avoid to perform a CT in 19 children (11%) who presented vomiting as the only risk factor of TBI. Three of these CT scans were pathological: in one case performed for vomiting, a mild epidural hematoma was demonstrated. The other two CTs performed for seizures in one case and because the child was less than 1 year old in the other demonstrated a fracture of the temporal and parietal bone, respectively. This might be regarded as an element in favor of a more liberal utilization of CT. However, given that none of these children did require neurosurgical treatment, the question about the opportunity of a wider utilization of CT after minor head injury remains open to debate.

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Conclusion The management of children with minor head trauma is still debated. Loss of consciousness and scalp swelling are risk factors predicting brain injury that require CT control, in accordance with current guidelines. The radiation risks posed by CT scanning in children must be balanced by the benefits. We believe that even though CT scans may be unnecessary in a vast majority of the cases (69% in this study), this rate of scanning is still justified by the number of abnormalities detected which require neurosurgical procedures (4.6% in this study).

Conflict of interest None.

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