DevelopmentalChildren under the age of 4 months- Tonic neck reflexes predominate- These reflexes can be demonstrated by passive or active motions of the head relative to the position of the body- This reflex is due to movement of endolymphatic fluid through the semiciruclar canals. These tonic neck reflexes are dependent on the integrity of vestibular and proprioceptive systems. Neck righting: In this test active / passive rotation of head from the midline to one side when the infant is lying supine will cause a rotation of the whole body .
Developmental4 - 6 months. Babies in this age group vary in theirdevelopmental achievements. Many normalinfants still have residual primitive tonic neckreflexes, while in others, righting responseswill appear. Both these conditions are normal.
Developmental6 - 18 months. This is a period of rapid motor and sensorydevelopment. The pyramidal tract becomesmyelinated. Integration of visual, labyrinthineand proprioceptive stimuli occurs during thisphase. Righting reflexes are elicited by anabrupt tilt of the patient to change thepatients centre of gravity.
DevelopmentalSince the optical and vestibular righting responses are identical the baby must be tested blind folded in order to eliminate visual cues. The most important of the righting reflexes is the head righting response. This can be obtained by picking up the infant from prone / supine position and bringing it to upright position by tilting the infant sideways, forwards or backwards. Every abrupt change of the head position in space will elicit vestibular head righting response. At the same time propping reactions of the extremities may be seen.
Prevalence of dizziness in children:• The population-based prevalence of vertigo and dizziness among school children has been reported to be 15%. In the literature, vertigo in children has received much less attention than vertigo occurring in adults. Even among otologists and child neurologists, the key clinicians providing appropriate diagnosis and treatment for vertiginous children, the differential diagnosis is not well established. The clinical picture of vertigo in children deviates from vertigo in adults, since young children do adapt very well to vertigo and dizziness and compensate a vestibular deficit quicker than adults (Niemensivu et al., 2006).
How are they Complaining??• - Delayed walking• - Clumsiness• - nausea• - episodic pallor and fatigue• - difficulty walking in Darkness, or uneven surface• - Headache blurred vision• - Difficulty reading in moving Vehicle• - Gaze stabilization problems
• Vertigo in children differs from that in adults, because of three main reasons.• Firstly, vestibular disorders are often ignored in children, because vertiginous manifestations are usually attributed to lack of coordination or behavioural problems.• Secondly, as children often lack the communication ability to describe accurately their symptoms, diagnosis is based less in history and much more in clinical examination and laboratory investigations.• Finally, although most diseases that cause vertigo in adulthood occur in childhood as well, their frequency may be different, depending on the age of the patient.
WHAT ARE OUR KEY ELEMENTS IN the HISTORY?? Knowledge of the Parents causes Investigations & interpretation
Arabic Version of Pediatric Dizziness Inventory QuestionnairePresentation for discussion of a Thesis Submitted For Fulfilment of the Master Degree in Audiology By: Mariam Magdy Medhat M.B., B. CH. Supervisors: Prof. Dr. Mohamed Ebrahim Shabana Professor of Audiology, Faculty of Medicine, Cairo University Dr. Abeir Osman Dabbous Assistant Professor of Audiology, Faculty of Medicine, Cairo University Dr. Noha Ali Hosni Lecturer of Audiology, Faculty of Medicine, Cairo University, Kasr El-Aini Faculty of Medicine Cairo University, 2011
Aim of the work• To develop an Arabic paediatric dizziness inventory questionnaire for the parents of dizzy children to address the balance complaints of their children by the information gathered from it. This evaluation will help to identify any balance dysfunction and to quantify the impact of dizziness on daily living and to describe the dizziness complaint, and helps to reach diagnoses of the balance dysfunction in children and directs us towards the necessary investigations to confirm this diagnosis.
Figure (2) : Distribution of the conclusion reached from the questionnaire in the cases. 1 Vestibular 1 5% 1 5% Cervical 5% General 210% Ocular 9 45% General/CVS 15% Neurological/Ocular 1 5% Ocular/Cervical 3 Vestibular / CVS 15% 1 5% Non specific (Ocular/General/ Neurological/Audiological association)
Figure (6): The ability of the questionnaire to match the diagnosis according to the referral for different categories. 100% 90% 80% 70% 60% Percentage Not matching 50% Matching 40% 30% 20% 10% 0% S l r/c ar r ar S l al c ca ca la e n CV ifi V l er ul vi cu cu vi /C ec en tib er er l/o / O al sp ar G C es er ca on ul V la gi tib N cu lo G es ro O V eu N
Conclusions:• We have developed an Arabic pediatric dizziness inventory questionnaire for the parents of dizzy children. A scoring system has been developed to address the balance complaints in children by the information gathered from it. Evaluation of dizzy children using our Arabic pediatric dizziness inventory questionnaire helped to identify balance dysfunction and was able to categorize the dizzy children by the affected system/systems.• The questionnaire and its scoring system were valid, being comprehensive enough to collect all the information needed to address the balance problem. The questionnaire was able to quantify the impact of dizziness on daily living, to describe the dizziness complaint that helped to reach a diagnosis of the balance dysfunction in children and to direct the clinician towards the necessary investigations to confirm this diagnosis.
Conclusions:• The Arabic dizzy children questionnaires categories matched the diagnosis on referral in 75% of cases. The sensitivity of the questionnaire in reaching the diagnosis was calculated at 75%. Its sensitivity in diagnosing vestibular category was 88.89%. The sensitivity in multi-system affection was 83.3%.• The Arabic dizzy children questionnaire defined a matched specific diagnosis for the cause of dizziness in 11/20 (55%) of cases.
Low muscle tone– Delay in holding head up– “Snuggly” baby– “Floppy baby”– Arching of back
Delayed disappearance of newborn reflexes– Moro– ATNR: Asymmetric tonic next response– Usually disappear by 6-7 months
Delayed motor milestones– Average deaf child walks at 14 months– Average child with Usher’s Type 1 walks at 20 mos– Delays sitting, crawling, climbing steps, hopping…– Speech delays
What do older children look like?• Clumsy• Unable to walk on a balance beam• Problems standing with feet together and eyes closed (Romberg test)
What do older children look like?• Love spinning, merry-go-rounds, water activities• Weak VOR: Challenges with reading – Gaze instability causes problems with acuity
Signs of poor vestibular function• Low muscle tone• Delayed loss of primitive reflexes• Delayed gross motor milestones• Developmental delays• Seizures• Nystagmus• Easy fatigability• Torticollis
Causes of dizziness in children A) Otologic: Congenital disorders: Syndromic hearing loss and vestibular dysfunction: – – Usher syndrome Pendred syndrome Examination – Enlarged vestibular Aqueduct syndrome – Congenital Long-QT Syndrome – CHARGE Syndrome Non-syndromic hearing loss and vestibular dysfunction Congenital anomalies of the skull base Traumatic disorders:• Head Trauma• Paroxysmal Positional Vertigo• Perilymphatic Fistula• Cochlear Implant Surgery History
Syndromes Over 500 nDNA syndromes known to affect the audiovestibular (AV) system.• Usher’s Syndrome (Type 1)• Waardenburg Syndrome• Pendred syndrome• CHARGE Syndrome• Brachio-oto-renal syndrome
Benign Paroxysmal Vertigo• * Common un recognized condition• * Paroxysm, Recurrent, non epileptic• * Pale, Sweaty, Fearful, May sway• * sudden onset, seconds to minutes duration• * no loss of conscious, with complete recovery• * Diagnosed By exclusion• * Migraine precursor
Causes of dizziness in childrenC) Psychological dizzinessD) Ocular disordersE) Systemic disorders (General causes)F) oto-toxic drugs Mainly History
Hearing ScreeningDo we have Vestibular screening
ENG/VNGCaloric irrigation: This test is performed only in children aged 4 and older. Ideally performed with the baby blind folded, in the supine position, with the head ventroflexed at 30 degrees. The child is also restrained. A ten second irrigation is a must for adequate stimulus. Recording should start immediatly after the onset of irrigation.
ENG/VNGIf the child is sleepy or irritable during the test the response may not be accurate. This test is a rather crude way of testing vestibular response to a stimulus. This test is hence performed only in cases of extreme doubts regarding the function of vestibular apparatus.Make it the last examination
ENG/VNGThere is a maturation pattern in the development of caloric evoked nystagmus response. The amplitude and the number of beats increase in the first three months of life. The intensity of the nystagmus is directly proportional to the gestational age and the weight at birth. The latency of the response decreases with the gestational age and increasing birth weight.
ENG/VNGOptokinetic stimulation:Optokinetic nystagmus can be evaluated in most children within three to six months of birth. As the child grows older, they learn to pay more attention to the moving images and better responses can be obtained in them. This nystagmus can be recorded in response to two speeds of rotation i.e. 3 degrees and 16 degrees per second.
ENG/VNGThe frequency, amplitude and speed of the slow component can be analysed in response to the two rotational speeds. The information obtained is helpful in the evaluation of overall quality of neurovestibular function.
DR. ABEIR OSMAN DABBOUS Assistant Professor of Audiology, Kasr El-Aini, Cairo University.
• The impairment of saccular function, indicated by the abnormal findings in the VEMP , is often associated with SNHL in the pediatric population.• With the increasing occurrence of pediatric patients with symptoms of dizziness, VEMP testing may be a means to evaluate unilateral vestibular function (Honaker and Samy, 2007).
Vestibular evoked myogenic potential (VEMP) inferior vestibular nerve Saccule medial vestibulospinal tract accessory nerve ipsilatral SCM The function of this sacculo-collic reflex is to stabilize the • head in response to unpredictable displacements (Halmagyi & Curthoys 2000).
VEMP Method Surface Electrodes : •Non-inverting active: middle third – of each SCM muscle,Inverting reference: supra-sternal –notch, or at each sternal insertion Ground: forehead. –
VEMP waveform (Murofushi and Kaga, 2009). Latency (in msec), P1 latency decreases with increasing rate.
Amplitude (in μV),• decreases with increasing rate above 5-Hz• EP ratio or the inter-aural difference ratio (IAD): [(Ar−Al)/ (Ar+Al), x 100], • a ratio of > 3:1 abnormal
An example of Normal IAD N23 P13 = 23.0 Amplitude= 38.13 uv = 14.6Rt IAD =0.023 Lt P13 Amplitude= 39.94 uv N23 = 15.2 = 22.2
N23 = 20.8 An example of abnormal IAD Amplitude= 77.81 uvRt P13 = 12.2 N23 = 22.0 IAD = 0.45 Lt Amplitude= 29.56 uv P13 = 14.2
VEMP amplitudedepends on: 1. Saccular function 2. Stimulus intensity, air-conduction 3. Electrode conduction & location 4. Linearly increases with the EMG level
Clinical utility of VEMP testing : sacculo-vestibular nerve function. assessment of vestibular nerve function: .1 acoustic neuromas – vestibular neuronitis – multiple sclerosis –diagnosis of superior semicircular canal dehiscence .2 syndrome, evaluation of Menières syndrome .3 Sensori-neural hearing loss. .4
VEMPs in a large Vestibular AqueductMost common anomalySudden fluctuation in pressure:1. progression of SNHL after head trauma,2. VEMP has greater amplitude and lower threshold (Sheykholesami et al, 2004).
VEMP in diagnosis of Superior Canal Dehiscence Syndrome Rare •a ‘third window’ : •pseudo-conductive HL, ABG at –low frequencies,Tullio phenomenon of –acoustically evoked vertigo &nystagmus,VEMP : –increased amplitudes –lowered threshold (70 dB) –(Colebatch et al., 1998; Streubel et al., 2001Brantberg et al., 1999; Ostrowski et al., 2001Minor et al., 2003; Mikulec et al., 2004).
Chronic otitis media• Chronic OM could delay and reduce the energy transfer of sound to the inner ear.• Improvement of postoperative VEMP response rate and p13 latencies in the patients with and without improvement in postoperative 500 Hz - ABG, provide evidence that the sound energy inducing a VEMP might be different from the energy producing the auditory perception (Wang et al., 2008).
Migraine and its equivalents• Migraine: the most common cause of episodic vertigo in children.• Allena et al., (2007) postulated that VEMP abnormalities in migraine are due to reduced serotonergic control of the reflex circuit, in particular of the vestibular nuclei.• Benign Recurrent (Paroxysmal) Vertigo or benign recurrent vertigo (BRV): – a major cause of vertigo in children – 30% have abnormal caloric responses, – 50% have abnormal VEMP responses (Ozeki et al., 2008).
Our VEMP Studies: in Migraineurs N23normal P13 25% N23 VEMP abnormalities P13 75% delayed latencies of P13 and N23.
VEMPs in Children with Cochlear Implants traumatic damage → absent VEMPs or decreased amplitude With CI on: electrical current spread at C level, apical channels → stimulates the IVN: present VEMPs or absent VEMPs if requiring higher current present VEMPs >50% intensities, but difficult (pain or facial nerve stimulation) (Jin et al., 2008).