Abstract
In recent years there has been renewed interest in evaluating vestibular function in young children. This revival is due, at least in part, to emphasis on evidence-based practice in health care and the realization that although many children describe or demonstrate symptoms and signs associated with vestibular dysfunction, a solid evidence base has not been established for which children will benefit from testing. Furthermore, there is a paucity of information regarding age-appropriate normative data for components of the vestibular test battery that are considered to be essential. Although there are many challenges associated with evaluating vestibular function in children, information that will help guide clinicians in their decisions of which children to test, which tests to select and/or modify, and how to interpret results is emerging. This chapter describes the five most common causes of vertigo and dizziness in the pediatric population and the reported vestibular findings associated with these disorders.
Keywords
Auditory neuropathy, Benign paroxysmal vertigo of childhood, Electronystagmography, Otitis media, Rotary chair, Trauma, Vestibular, Vestibular neuritis, Videonystagmography
Introduction
There are many disorders that can cause “dizziness” in the pediatric population. In 1999, Russell and Abu-Arafeh published an epidemiological study showing that in their sample, 15% of school-age children had experienced at least one episode of vertigo in the previous year. In a further effort to describe the prevalence and causes of dizziness in the pediatric population, O’Reilly et al. searched electronic medical records (i.e., ICD-9 codes) of 561,151 inpatient and outpatient visits during a 4-year period. These investigators reported that approximately 1% of this cohort met criteria for presenting with a primary complaint related to balance. Further analysis revealed that 2283 patients (0.4%) received a diagnosis of unspecified dizziness, and of these, 6.2% were diagnosed with a peripheral cause of dizziness while 4.1% were diagnosed with a central cause. The total prevalence of diagnoses related to balance in the records reviewed was determined to be 0.45%. These data serve to highlight the relative rarity of seeking medical attention for symptoms of dizziness and imbalance in young children. Numerous investigators have described the most common disorders causing vertigo and imbalance in children in their clinics. Even though these reports originate from different clinics and regions of the world, there is surprisingly good agreement regarding primary causes of dizziness in the pediatric population. Nevertheless, children experiencing vertigo and imbalance have received less attention in the literature than their adult counterparts. This is most likely due to the difficulty that young children have in describing their symptoms, coupled with challenges that exist for clinicians in working through the differential diagnostic process with children. Despite these limitations, it is now known that the most common disorders in children that cause dizziness manifest themselves as abnormalities on quantitative balance function testing (i.e., rotary chair testing, videonystagmography/electronystagmography, and vestibular evoked myogenic potential [VEMP] testing).
Background
Assessment of vestibular system function in the pediatric population is gaining interest for several reasons. First, determining vestibular system integrity can assist physicians in diagnosing impairment and in defining the most appropriate course of treatment. Second, some children with dizziness and balance problems have serious health issues, and vestibular system assessment can help identify patients whose symptoms may stem from neurologic impairment secondary to intracranial abnormality (e.g., head trauma, brain tumor) versus developmental delay. However, unlike in adults, episodic vertigo occurs rarely in children and may manifest itself in many forms. For example, a child with acute vestibular system impairment may present with many of the same symptoms as adults (e.g., vomiting, nystagmus, hearing loss, ataxia) or may have subtler symptoms such as visual disturbance, motor delay, or headache. As with adults, children with vestibular disorders may also present with loss of vestibular function, which is progressive or chronic, thereby affecting development of postural control. Identifying whether dizziness in a pediatric patient is of vestibular origin requires a team approach, beginning with an assessment by a physician. During this initial visit, a detailed case history should be obtained along with comprehensive neurologic and otologic examinations. Once neurologic impairments are excluded, quantitative balance function testing may help identify both peripheral and central vestibular system deficits.
Despite the fact that dizziness and vertigo occur in children, there are few dizziness clinics that have made a commitment to test this population. One explanation for this is the challenge of extracting clinical and laboratory information from children. According to Wiener-Vacher, children will often not report vertiginous symptoms because of their inability to verbalize the abnormal sensations they are experiencing. Vestibular disorders in young children often are dismissed by professionals and caregivers alike, and the symptoms are consequently attributed to behavioral problems (i.e., finding ways to attract attention) or simply being “clumsy.” Additionally, diseases that affect the vestibular system in adults have a different frequency of occurrence in the pediatric population. For example, benign paroxysmal positional vertigo (BPPV) is generally quoted as the most common form of vertigo in adults. It has been estimated to have a prevalence of 2.4% in the general adult population. In children, BPPV has been reported to occur in up to 6% of those presenting with dizzy concerns. This means that the provider must approach the diagnosis of childhood dizziness and vertigo with a very different background of knowledge. Finally, although there continues to be interest in the development of techniques for assessing the vestibular system in adults, the same energy has not been directed toward adapting these techniques for application to children. One of the pioneers in the assessment of vestibular function in the pediatric population was Dr. David Cyr who worked at the Boys Town Institute. Much of his work in the 1980s focused on adapting existing adult protocols for use with children. Many of these adaptations are still in use today (see Chapter 4 ). Although interest in the assessment of the vestibular system in children has led manufacturers to develop both age-adjusted pupil tracking algorithms and age-appropriate visual targets, the majority of manufacturers at the time of this report do not offer videonystagmography goggles that are appropriately sized for children. Having equipment that allows for accurate assessment of children is critical because many disorders causing dizziness and vertigo in children have a vestibular origin. Although the clinical utility of quantitative balance function testing is well-documented in children, continued research and development in balance assessment techniques will further our understanding of pediatric dizziness and vertigo.
Assessing Dizziness Handicap in Pediatric Patients
It is now standard practice to evaluate the impact that balance disorders have on an individual’s ability to participate in age-appropriate activities and document any restrictions that may be imposed by the impairment. This is referred to in the literature as a patient’s dizziness-related quality of life (DRQoL). There are a number of important reasons to measure patients’ DRQoL. First, these metrics provide the treating clinician with information that can be used to design and guide treatment of a patient’s symptoms. Specifically, a clinician can administer a handicap measure to a patient, provide treatment designed to mitigate the origin of the impairment, and then reassess to determine if there has been any change. Historically, psychometric investigations have been performed describing how much change in the score is needed to be considered significant. Having outcome measures that include the patient’s perception of their symptoms in addition to findings on the vestibular test battery as well as their subsequent response to intervention provides a multidimensional profile of the patient’s symptom status. Secondly, it has been shown that there is often a disparity between a patient’s symptoms and their findings on vestibular function studies. That is, there are no semiobjective measures of vestibular impairment that are strongly predictive of dizziness handicap and/or disability. Lastly, in the current health care environment, evidence-based practice is important to all parties involved, including insurance carriers.
DRQoL has been typically assessed using validated self-report measures. These appraisals are most commonly done in a paper-pencil format, are brief to complete, and are psychometrically robust (i.e., test-retest reliability is high). There are a number of tools that assess DRQoL including the Vertigo Handicap Inventory and the Dizziness Handicap Inventory (DHI). Until recently, there was no single measure of dizziness handicap and/or disability for children. In 2015, the Vanderbilt Pediatric Dizziness Handicap Inventory of Patient Caregivers (DHI-PC) was introduced and validated for use with children aged 5–12 years. Questions on the DHI-PC are written in such a way that they may be answered by the child or their proxy. The DHI-PC form is shown in Fig. 5.1 .
Differential Diagnosis
The differential diagnostic process is more complex in children reporting dizziness or balance problems than in adults for several reasons. First, symptoms of dizziness can manifest differently in children than in adults. Moreover, young children have limited verbal skills and often the clinician must rely on the caregiver’s observations for the case history. Accordingly, determining which pediatric patients should receive vestibular testing can be difficult. In this regard, several investigators have designed structured case histories to be used for the evaluation of vertiginous children. One example set forth by Ravid et al. consists of a set of structured questions coupled with a computer algorithm designed to aid in the differential diagnosis of the dizzy child.
To validate the effectiveness of the questionnaire, the authors performed a retrospective analysis of data collected from all children presenting with dizziness to their clinic over a 2-year period. Responses to the structured questionnaire were compared with the computer algorithm, and both were compared against the final diagnoses in the medical record. The questionnaire-derived diagnoses matched the medical record diagnoses in 92% of the patients, and results of the computer-assisted algorithm were identical to the final diagnoses in the medical record in 84% of patients. Similarly, Niemensivu et al. evaluated a structured case history for the diagnosis of dizziness in children and, following thorough clinical examination and vestibular laboratory testing, found that the most common disorders identified using this approach were otitis media–related vertigo, migraine-associated dizziness, and benign paroxysmal vertigo of childhood (BPVC).
In our experience, using a structured case history coupled with a decision tree has worked well to identify patients who will benefit from vestibular testing. For instance, if the algorithm suggests that the patient may have labyrinthitis, then quantitative testing can be performed to determine whether the child has a peripheral impairment, whether it is unilateral or bilateral, if unilateral how severe, and whether the child is compensating centrally for the impairment. Conversely, if a child presents with chronic dizziness, no hearing loss, and a documented neurologic deficit(s), balance function testing would most likely not be indicated, and other issues would need to be ruled out (e.g., degenerative disease or posterior fossa tumor) using different techniques. This information is useful to both the physician and the pediatric physical therapist when considering management options. This approach also streamlines the differential diagnostic process and affords the physician the ability to be selective in determining which tests will be beneficial in deriving the diagnosis and which will not.
Recently, Pavlou, Whitney, and associates developed and validated the Pediatric Vestibular Symptom Questionnaire (PVSQ). This instrument is designed to identify and quantify subjective vestibular symptoms (e.g., dizziness, imbalance) in children aged 6–17 years. The study also had a secondary component, which described relationships among symptoms in children with vestibular impairment versus dizziness or imbalance secondary to concussion. This instrument can be used not only as an indicator for whether a child requires further assessment to investigate a potential balance impairment, but also as a metric that can be used to evaluate the effectiveness of treatment ( Fig. 5.2 ).
The Most Common Disorders
After otitis media, the two most common conditions reported in the literature causing dizziness/vertigo in children are migraine headache and BPVC. The next most common disorders are trauma and vestibular neuritis. Interestingly, all of these disorders can result in patients who have abnormal findings on balance function testing. This reinforces the importance of having vestibular testing available in the pediatric dizzy clinic. Two recent studies illustrate this argument well. First, a recent report by Szirmai evaluated vestibular function in children (<14 years of age, n = 66) and adolescents (14–18 years of age, n = 79). The author reported that migrainous vertigo (MV) was the most common disorder causing dizziness in this cohort, followed by extravestibular disease (e.g., anxiety, panic disorder) and then labyrinthitis. Only 36% of the patients in this study demonstrated normal vestibular system function. In the group of adolescents, extravestibular disease was the most common cause of vertigo followed by migraine. Only 39% of the adolescents demonstrated normal vestibular results.
A report by Wiener-Vacher reviewed the most common vestibular disorders in over 2000 children over a 14-year period. Patient records were examined retrospectively to determine the most common diagnoses in children presenting with dizziness and vertigo. Consistent with many earlier reports, the most commonly diagnosed vestibular disturbance was MV, which was responsible for nearly 25% of patients. BPVC represented 20% of the diagnoses, and cranial trauma and ophthalmologic disorders each accounted for 10% of the diagnoses. In this cohort, vestibular neuritis (5%) and posterior fossa tumors (<1%) were less often encountered.
Table 5.1 provides a summary of findings from a series of studies each describing the most frequent causes of pediatric dizziness/vertigo that are encountered clinically. Characteristics of these conditions (i.e., pathophysiology and balance function test findings) are described.
| Balatsouras et al. | Bower and Cotton | Choung et al. | D’Agostino et al. | Erbek et al. | Ravid et al. | Riina et al. | Weisleder and Fife | Szirmai | Wiener-Vacher | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Total subjects | 832 | % | 54 | 34 | 55 | 282 | 50 | 62 | 119 | 31 | 145 | More than 2k | |
| Migraine | n (%) | 143 | 17.19 | 11 (20.4) | 4 (11.8) | 17 (30.9) | 15 (5.4) | 17 (34) | 24 (39) | 17 (14.3) | 11 (35.5) | 27 (18.6) | 25% |
| BPVC | n (%) | 133 | 15.99 | 9 (16.7) | 5 (14.7) | 14 (25.5) | 60 (21) | 6 (12) | 10 (16) | 23 (19.3) | 6 (19.4) | 20% | |
| Otitis media | n (%) | 22 | 2.64 | 5 (9.2) | 5 (14.7) | d | d | 12 (10.1) | |||||
| Viral infection | n (%) | 132 | 15.63 | 15 (27.7) | 4 (11.8) | 1 (1.8) | 53 (18.8) | 2 (4) | 9 (14) | 14 (11.8) | 32 (22.1) | 5% | |
| Trauma | n (%) | 109 | 13.1 | 3 (5.5) | 3 (8.8) | 4 (7.3) | 85 (30.3) | 2 (3) | 6 (5) | 6 (4.1) | 10% |
Migraine-Associated Vertigo in Children
A number of epidemiologic investigations of dizziness in childhood have been published recently. Pacheva and Ivanov reported their observations from a sample of 2509 pediatric migraine patients who were evaluated in a pediatric neurologic clinic. These investigators reported that migraine variants were responsible for symptoms in 24% of the patients, basilar migraine (BM) was diagnosed in 6% of patients, and BPVC and hemiplegic migraine were responsible for 5% and 4% of diagnoses, respectively.
Teixeira et al. reported findings of patients with migraine equivalents who were evaluated in an outpatient pediatric neurology clinic. Of the 674 pediatric headache patients, 38 (5.6%) had migraine equivalents, and the majority were males. Further review revealed that 15 patients had abdominal migraine, 12 had BPVC, 5 had confusional migraine, 3 had aura without migraine, 2 had paroxysmal torticollis, and 1 patient had cyclic vomiting. A family history of migraine was common.
Marcelli et al. conducted an investigation focusing on BPVC, which is one of the most common pediatric migraine equivalents. It was the authors’ objective to characterize the progression of BPVC by conducting a 10-year longitudinal investigation with a sample of 15 children. These investigators reported that 67% of the patients reported either the onset or worsening of migraine over this interval. Furthermore, the neurootologic assessment was abnormal for 20% of patients during the symptom-free period and was abnormal for 67% of patients during the episode.
Another epidemiologic investigation by Raucci et al. reported their experience assessing vertigo and dizziness in a pediatric emergency department over a 5-year period. They found that dizziness and/or vertigo was the presenting complaint in 616 out of a total of 248,834 visits (or 2.5 dizzy patients per 1000 visits). The most common dizziness disorders were migraine, which accounted for 25% of visits, and BPVC, which accounted for 6% of the diagnoses.
Sommerfleck et al. reported the primary dizziness diagnoses of 206 patients aged 1–18 years (median age: 10 years). These investigators commented that 39% of the sample met criteria for definite vestibular migraine and another 13% satisfied criteria for probable MV. Interestingly, before puberty more boys than girls had migraine diagnoses. Following puberty the sex ratio favored girls. The most common disorder affecting children aged 1–5 years was BPVC. For the group between 6–11 and 12–18 years of age, the most common disorder was vestibular migraine.
The general view is that vestibular migraine coupled with BPVC account for approximately 37% of dizzy/vertiginous diagnoses in pediatric patients. The dizziness is described as moderate to severe in intensity and should be present for at least 5 minutes and no more than 72 hours. In fact, one-third of patients experience dizziness lasting minutes, one-third experience dizziness lasting hours, and one-third experience dizziness lasting days. Approximately 10% of patients experience short-lasting dizziness (seconds). Dizziness may precede or follow the headache, and the dizziness perception may be either spinning or a rocking sensation.
There are a number of “episodic syndromes” that may be migraine variants that can affect pediatric dizzy patients. These syndromes include infantile colic, benign paroxysmal torticollis, benign paroxysmal vertigo, cyclical vomiting syndrome, and abdominal migraine. These are referred to as episodic syndromes because head pain may be completely absent. These variants may occur in isolation or may coexist with other migrainous diagnoses. Furthermore, the prevalence of these syndromes has been reported to range from 2% to 4% of the pediatric dizzy population.
Treatments for vestibular migraine range from sleep hygiene and diet control to prophylactic treatment with medications that include flunarizine, propranolol, metoprolol, topiramate, clonazepam, lamotrigine, nortriptyline, amitriptyline, verapamil, and lomerizine.
As mentioned previously, the most common diagnosis in children with vertigo and dizziness is migraine headache or migraine equivalent, although the temporal relationship of headache and dizziness has been reported to be variable. That is, vertigo may precede, follow, or occur simultaneously with dizziness/vertigo, and often there are accompanying symptoms such as nausea and/or sensory distortions (i.e., sensitivity to light, sound, taste, smell, and motion). The clinical features of migraine in children can be different from those seen in adults. In childhood, migraines often are localized to the frontal or periorbital region, last less than 2 hours and may not manifest themselves as the typical throbbing pain often described by adults. Approximately 20% of children with migraine have associated dizziness. There are three commonly reported migraine variants that can produce abnormal findings on quantitative vestibular system testing : BM, MV, and BPVC. Reports estimate that BM occurs in 3%–19% of children with migraine and usually occurs around age 7 years. Many migraines present with an aura consisting of different sensory sensations (e.g., olfactory, visual, or vestibular). BM has been described in the literature as presenting with an aura consisting of audiovestibular manifestations, such as tinnitus, loss of hearing, acute imbalance, and vertigo. Usually, the neurologic examination in pediatric patients with BM is normal. According to Eggers, only a very small proportion of patients with MV meet criteria for BM.
Etiology and Pathophysiology of Migraine
The pathophysiology of vestibular migraine is currently unresolved. In BM, the root cause has been suggested to be asymmetrical activation of brainstem vestibular nuclei or defective Ca 2+ channels, which are shared by the brain and the inner ear. MV is considered by most to be a distinct entity, and as with BM the pathophysiology of MV is still not completely understood. Investigators have set forth hypotheses, which include cortical spreading depression affecting the parietoinsular vestibular cortex, and changes in activity between the parietal cortex and vestibular nuclei.
Balance Function Findings in Children With Migraine
Laboratory findings in patients with MV can consist of both central and peripheral impairment and have been well-documented in adults. Olsson evaluated 50 patients with BM and 49 of the participants demonstrated abnormal ocular motor testing. When caloric test findings are combined across studies, the frequency with which unilateral impairment was observed ranged from 8% to 60% of patients. Marcelli et al. reported vestibular findings in 22 children diagnosed with migraine. In this sample, 73% of participants with MV demonstrated either peripheral or central vestibular abnormalities. The vestibular manifestations varied and included spontaneous-positional nystagmus, post head-shaking nystagmus, benign paroxysmal positional vertigo, vibration-induced nystagmus, the absence of VEMPs, and reduced responses to caloric stimuli—unilaterally or bilaterally. Vestibular system testing may be a useful tool in the differential diagnosis of children with migraine, especially in those children whose headaches are associated with vertigo or dizziness.
Benign Paroxysmal Vertigo of Childhood
BPVC was initially reported by Basser in 1964, who described the clinical presentation of BPVC in 17 children ≤ 4 years of age. Primary symptoms include episodic attacks of vertigo lasting from seconds to minutes resulting in the child being unable to stand without support. Additional symptoms include nystagmus, tinnitus, pallor, diaphoresis, and vomiting. BPVC is a pediatric migraine equivalent recognized by the International Headache Society classification system. During attacks of BPVC, there is no loss of consciousness, and there is a complete recovery following an attack. A child who is capable will describe a sensation of spinning. The age of onset of BPVC has been reported to occur before 4 years of age and is rarely seen after 8 years of age. In an epidemiologic study by Russell and Abu Arafeh, it was determined that 2% of school-age children met criteria for BPVC, defined as at least three transient episodes of the sensation of rotation, either of the child or of the surrounding environment severe enough to interfere with normal activity and not associated with loss of consciousness or any neurologic auditory abnormality.
Etiology and Pathophysiology of Benign Paroxysmal Vertigo of Childhood
While the pathophysiology of BPVC is currently unknown, there is strong supporting evidence that BPVC is a migraine headache variant. Many children with BPVC will go on to develop migraine later in life. There is mounting evidence suggesting that in many patients, BPVC is vascular in origin. For example, an episodic vasospasm could result in ischemia to the inner ear culminating in end-organ impairment and consequently vertigo. A central mechanism postulated is an interruption in blood flow to the vestibular nuclei and associated pathways. Regardless of etiology, the variable nature of laboratory findings makes diagnosing this disorder difficult. Currently, the diagnosis of BPVC is primarily dependent on a reliable and characteristic history.
Balance Function Findings in Children With Benign Paroxysmal Vertigo of Childhood
There is great variability in quantitative vestibular test results obtained from patients with BPVC. Several studies have reported that children with BPVC commonly present with significant bithermal caloric asymmetry. However, other investigators have found no such relationship. Mierzwinski et al. evaluated 124 children with vertigo, 13 of whom presented with characteristics commonly associated with BPVC. Results showed that of this subset of 13 patients, 5 had normal electronystagmography (ENG) test results. In addition, one patient was found to have significant unilateral caloric weakness, and the other seven patients had either central vestibular impairments or a mixture of peripheral and central vestibular system deficits.
Trauma
Traumatic brain injury (TBI) in young children is common, and significant attention has been given to these conditions recently because of increased public awareness of concussion in sports. A TBI is disruption of typical brain function following a sudden blow to the head or body. This can occur because of direct trauma to the head (i.e., blunt force, penetrating injury) or indirectly through whiplash mechanisms. The Centers for Disease Control and Prevention have stated that children under 14 years of age comprise approximately 500,000 emergency department visits for TBI each year. Most TBIs are classified as “mild” or “concussions” with a large proportion occurring because of sports- or recreation-related injuries. An estimated 3.8 million sports-related concussions occur in the United States annually with fewer than 10% seeking evaluation in emergency departments. Unfortunately, these numbers may not represent the scope of concussion-related injuries, as up to half of concussions may go unrecognized or unreported.
Postinjury, children may present with a wide range of symptoms such as headache, dizziness, imbalance, cognitive impairment, changes in personality, and sleep disturbance. Vestibular-related abnormalities noted at initial presentation have been associated with delayed return to academics and sports or recreational activities.
Etiology and Pathophysiology of Trauma
Children with TBIs may demonstrate peripheral, central, or mixed vestibulopathy. The majority of reports in the literature regarding objective measurement of vestibular dysfunction following trauma have been collected in adults. In adults, peripheral vestibulopathy has been associated with direct end-organ damage, especially to otolith organs. Labyrinthine concussion is thought to be due to microscopic hemorrhages or damage to the sensory epithelium. Perilymph fistula, posttraumatic endolymphatic hydrops, superior semicircular canal dehiscence, and BPPV have also been reported following trauma. Peripheral vestibulopathy has been associated with penetrating or blunt head trauma, especially when temporal bone fracture occurs. If the vestibular labyrinth and/or vestibular nerve are affected following head injury, children can experience severe vertigo with nystagmus and nausea consistent with acute unilateral peripheral vestibular impairment. Posttraumatic BPPV has a reported incidence of 11% in adults, and while pediatric vestibular clinics report the prevalence of BPPV between 5% and 12%, the rate of postinjury BPPV is not yet known. Case studies have demonstrated this possibility and BPPV should be considered for children with posttraumatic vertigo.
Central vestibulopathy associated with dizziness and imbalance is common following head injury and may be related to various causes. These include diffuse axonal injury, migraine-associated dizziness, and/or psychologic considerations. These are not exclusive categories, and a child’s dizziness may be related to multiple underlying causes. Furthermore, it may be that a child presents to the clinic with both peripheral and central involvement, which can lead to complicated management. In general, concussions are minimally associated with peripheral vestibulopathy ; however, up to 81% of adolescent and collegiate athletes report difficulty with dizziness and imbalance postinjury, thought to be related to atypical central vestibular functioning. Alhilali et al. hypothesized that patients with mild TBI likely present with dizziness symptoms because of diffuse axonal injury. This study evaluated 30 children and adults with reported dizziness and/or imbalance following mild TBI. All patients were evaluated using tract-based spatial statistics of diffusion-tensor imaging on magnetic resonance imaging (MRI). These data provided radiologic evidence of atypical cerebellar and fusiform gyri function, which are regions associated with sensorimotor processing, balance, and visually guided movement. Furthermore, these authors noted that injury to the cerebellum in those patients with mild TBI and vestibular symptoms was associated with prolonged symptom recovery, which has previously been noted only using clinical signs and symptoms.
Balance Function Findings in Children With Trauma
Objective vestibular diagnostic testing is rarely documented in children following head injury, and currently available studies often provide mixed results because of the small number of participants as well as the wide range of likely injuries included in the sample. Peripheral end-organ damage should especially be suspected if the child also presents with hearing loss. Several cases of posttraumatic perilymph fistula have been reported. For example, Neuenschwander et al. and Kim et al. described cases of ataxia and/or vertigo following penetrating and blunt head injuries in children. Three of the five case studies resulted in diagnoses of perilymphatic fistula, one with dehiscence of the oval window, and one with ossicular chain damage without surgical evidence for fistula. All of the children in these case studies demonstrated hearing impairment; four were sensorineural and one was conductive. Spontaneous nystagmus was observed in three of the five patients. Although not commonly reported, these studies demonstrate the possibility of perilymph fistula presenting in pediatric head trauma patients and should be considered, especially in the presence of concurrent hearing loss.
In one of the most comprehensive studies describing effects of blunt head injury in children, Vartiainen et al. described findings in 199 children. These investigators compared 61 children treated for acute blunt head injury with 59 age-matched controls. An additional 138 children with previous diagnosis of blunt head trauma were invited for examination to determine posttraumatic findings in the long term. Thirty-nine patients (19.6%) had sustained skull fracture. The results of this study are summarized in Table 5.2 .
