|Year : 2016 | Volume
| Issue : 2 | Page : 58-60
Importance of re-evaluating hearing loss in children, case study
Khairy Abulnasr MD
Department of Otolaryngology, Saudi German Hospitals, Jeddah, Saudi Arabia
|Date of Submission||30-Nov-2016|
|Date of Acceptance||19-Dec-2016|
|Date of Web Publication||20-Mar-2017|
Department of Otolaryngology, Saudi German Hospitals, PO Box 2550 Jeddah 21461, Jeddah
Source of Support: None, Conflict of Interest: None
Case study of 5 years old boy presenting with unilateral hearing loss. the importance of combing the results of oto-acoustic emission and ABR test is crucial to reach diagnosis. the MRI brings the radiological image which concludes the diagnosis.
Keywords: auditory canal stenosis, auditory neuropathy, oto-acoustic emission
|How to cite this article:|
Abulnasr K. Importance of re-evaluating hearing loss in children, case study. Adv Arab Acad Audio-Vestibul J 2016;3:58-60
A 5-year-old boy was referred to me for a hearing test because he did not pass the hearing screening test in his right ear. His parents reported that he said ‘Eih?’ frequently, and now he is turning his head to the source of sound. He had experienced a few ear infections that responded well to antibiotics. The parents mentioned a maternal aunt who is ‘nearly totally deaf’ and wears binaural hearing aids.
| Initial test results|| |
Otoscopic examination showed bilateral clear ear canal and a normal-appearing tympanic membrane. The consent was provided by the ethical committee of Saudi ENT Society.
Tympanograms were within normal limits bilaterally, with the absence of acoustic reflexes in the right side. The otoacoustic emission (OAE) test showed pass response bilaterally.
Behavioral play audiometry testing with speech reception threshold was carried out. The child seemed bright and cooperative enough for routine testing. I obtained no response until 80 dB. Thereafter, I switched to the left ear and he responded appropriately. I tried speech reception thresholds again with the same results. Even on reversing the earphones, the same results were obtained. When the behavioral tests were completed, the results indicated normal hearing in his left ear and a profound hearing loss in his right ear.
The child’s parents were informed of these results, and we scheduled him to return for a retest to confirm these findings.
One week later, the boy returned for a follow-up test. Tympanograms were within normal limits. In addition, acoustic reflexes were evaluated, which were normal in his left ear (80–90 dB) and questionable in his right ear (105–115 dB at 500 Hz only).
Unexpectedly, transient evoked OAEs were present in both ears. The right ear was reduced in amplitude compared with the left, but not what I would expect to see with a profound hearing loss ([Figure 1]).
|Figure 1 Audiological tests of a 5-year-old boy. ABR, auditory brain stem response.|
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I repeated the behavioral tests with the same results that I obtained the first time. Bone conduction scores were not obtained at this time because I felt I was reaching the limits of a 5-year old, and the tympanograms were normal on two occasions. As the condition is difficult to be explained on the basis of unilateral auditory neuropathy, I advised them to take an appointment to confirm the condition using the auditory brain stem response (ABR) test. The ABR test was scheduled and performed and revealed the following. Findings are consistent with normal hearing sensitivity in the left ear and a neural hearing loss in the right ear consistent with auditory dyssynchrony. Normal hearing in the left ear is adequate for speech and language development at this time. The parents were not completely satisfied with the diagnosis or explanation. They were asking for imaging (namely, MRI) as the gathered findings were difficult to understand, and they were scheduled for MRI.
Findings of MRI
Evaluation of the right inner ear structures demonstrated thinning of the right cochlear nerve. The vestibular nerve was present but was small in caliber. The internal auditory canal was somewhat small in diameter. There was atresia versus severe stenosis of the cochlear nerve canal. The right modiolus was thickened. The cochlea had the normal amount of turns, and the vestibule semicircular canals appeared normal.
The left inner ear structures, cranial nerves VII and VIII complex, and the internal auditory canal were normal. Additional normal findings were also presented as regards sinuses, etc.
The results are consistent with atresia versus severe stenosis of the right cochlear nerve canal and the cochlear nerve and deficiency described above.
According to the MRI, the cochlea on the right side is normal, which would explain the present Transient Evoked Otoacoustic Emissions results. The cochlear branch of the VIIIth cranial nerve is thinning, which would explain the absent ABR result and the severe-to-profound hearing loss on behavioral testing.
| Conclusion|| |
- It is recommended that one re-evaluates what one thinks and says about any test findings.
- The OAE is not a hearing test, and just because a child passes their newborn hearing screening test, it does not mean that they have normal hearing.
- It was difficult to convince that the disorder was auditory neuropathy (AN). An MRI test was needed to confirm the diagnosis and exclude any radiological anomalies.
So what? Does any of this really make a difference? The bottom line is that we have a 5-year-old boy with a unilateral profound hearing loss. How important is it that we know why he has that loss? From a purely clinical standpoint, I think that it is poignant because it brings home the importance of understanding what our tests really say about the hearing mechanism and the auditory system (i.e. is it working or not working?). Moreover, although it may not make a large difference in the boy’s current treatment plan, I do know that the boy’s mother is grateful for understanding the reason for her son’s hearing loss and that it is at least possible the boy may benefit from this knowledge in the future.