Otorhinolaryngology News

Text Box: The need for neonatal hearing screening program was borne out of the evidence that only 1/2 of hearing impaired children demonstrate 'risk factors' and that late identification of hearing loss results in poorer outcome than earlier identification and intervention. The crude Health Visitor Distraction Test soon gave way to more objective screening tests, mainly OAE and automated ABR (A-ABR) - none of which assess hearing as such. Because the AABR has a low false positive rate than OAE, the common practice is for some centers to use TEOAE as first screening tool, with AABR reserved for those who failed OAE. A not-too-recent report of multisite study (White, Vohr, Meyer at al; Am J Audiol. 2005 Dec;14(2):S186-199) designed to assess efficacy of this 2-stage OAE /AABR protocol observed that as much as 23% of children who passed the AABR were identified with permanent hearing loss at 8-12 months, and emphasized the need for continuous monitoring beyond neonatal period using a battery of test procedures.
Abstract: PURPOSE: Most newborns are screened for hearing loss, and many hospitals use a 2-stage protocol in which all infants are screened first with otoacoustic emissions (OAEs). In this protocol, no additional testing is done for those passing the OAE screening, but infants failing the OAE are also screened with automated auditory brainstem response (A-ABR). This study evaluated how many infants who failed the OAE and passed the A-ABR had permanent hearing loss (PHL) at 8-12 months of age. METHOD: A total of 86,634 infants were screened at 7 birthing centers using a 2-stage OAE/A-ABR hearing screening protocol. Of infants who failed the OAE but passed the A-ABR, 1,524 were enrolled in the study. Diagnostic audiologic evaluations were performed on 64% of the enrolled infants (1,432 ears from 973 infants) when they were 8-12 months old. RESULTS: Twenty-one infants (30 ears) who passed the newborn A-ABR hearing screening were identified with PHL when they were 8-12 months old. Most (71%) had mild hearing loss. CONCLUSIONS: If all infants were screened for hearing loss using a typical 2-stage OAE/A-ABR protocol, approximately 23% of those with PHL at 8-12 months of age would have passed the A-ABR.

Text Box: With so much still unclear about the precise etiopathogenesis of Meniere's disease (MD), and with the MD presentation in children known to be a rarity, this recent report from Korea ( Choung, Park & Kim, J Laryngol Otol. 2006 Apr;120(4):343-52.) emphasized the need to watch out for high tone loss in initial audiogram in suspected children with vertigo.
Abstract: Classical Meniere's disease is rarely found in children and literature regarding it is scarce. In general, the frequency of Meniere's disease in children is only 0.4-7.0 per cent of that in adults. The progression pattern of Meniere's disease in children is not known well. Here, we report three cases of Meniere's disease in children less than 15 years old, treated over nine years. The three cases comprise 14- and 13-year-old boys and a nine-year-old girl. Two of the three patients initially complained only of recurrent bouts of vertigo, without any tinnitus, ear fullness or hearing impairment. In all three cases, the early pure tone audiograms showed only high tone frequency loss, regardless of subjective hearing loss, and the decrease in the hearing threshold was observed one to eight years after the dizziness attacks began. The hearing threshold was usually decreased to a level of mild or moderate hearing impairment. After diuretic treatment, vertigo was generally well controlled, and some cases showed improvement in hearing. Of the total number of patients with Meniere's disease who visited our department over nine years, 2.6 per cent (3/114) were children, and the overall incidence of Meniere's disease in children with vertigo was 2.0 per cent (3/147). In conclusion, Meniere's disease in children rarely develops and may have characteristics of high tone loss in initial audiograms.

Text Box: Inside This Issue
· Failed OAE and NNHS
· High Tone Loss & Paediatric MD
· Nasolabial cyst - what origin, What ultrastructure...?.
* Case of the Week

Case Review

Clinical Photo of The Week

A 41-year old male presented with progressive painless right jaw swelling of 2 years duration. He had no associated dental, or pharyngeal symptom, and denied any antecedent trauma. The swelling showed no increase in size during meals. Examination revealed the mass shown in this picture. The mass was cystic, non-tender, and there was no palpable bruit or associated palpable cervical lymphadenopathy. The facial nerve was intact. Oral and pharyngeal examination was negative. A well circumscribed intra-parotid soft-to-firm mass measuring 4.5 X 6 cm was found at superficial parotidectomy.

What is the Diagnosis?

1. 8th International Otology Course of the Jean Causse Ear Clinic June 22-24, 2006; Béziers, France

2. 110th American Academy of ORL, Head & Neck Surgery Annual Meeting & OTO EXPO, September 17-20, 2006; Toronto, Canada.

3. 42nd South African ENT Congress joint meeting with the British Association of Otolaryngology - Head & Neck Surgery, October 29-November 1, 2006; Cape Town, South Africa.

This not-too-recent study from Taiwan (Huang, Liu, Huang & Chien, Laryngoscope. 2006 Feb;116(2):307-11. ) designed to throw more light on the confusion surrounding the origin, cell type and ultrastructure of nasolabial cyst observed that the lining epithelium is non-ciliated columnar, with the microvilli observed in place of cilia.

Abstract: OBJECTIVE: Nasolabial cyst is an uncommon midfacial cyst. It is considered to be a developmental anomaly arising from the rest of nasal respiratory epithelium. Although the cyst is a well-recognized entity, there remains some confusion of its origin, cell types, and ultrastructures. Based on the routine light microscopic study, some authors reported the epithelial cells of the inner lining of the nasolabial cyst were ciliated; some others reported they were nonciliated. To clarify this, a scanning electron microscopic study is needed. STUDY DESIGN: This was a prospective clinical series. METHODS: A transnasal marsupialization method was used to treat 10 patients with nasolabial cyst. With patients under local anesthesia, the roof of the cyst wall and a disk of nearby nasal mucosa were excised together with a sickle knife and scissors. Surgical specimens were dissected and processed for scanning electron microscopy and histochemistry. Patients were followed up for 8 to 65 months. RESULTS: Marsupialization of cysts was successfully performed on all patients. Electron microscopically, the inner surface of the nasolabial cysts in all the cases was lined with nonciliated columnar epithelium consisting chiefly of goblet cells and basal cells. It is suggested that goblet cells contributed to clear, thin, and yellow mucus present in the cyst lumen. Instead of cilia, these epithelial cell surfaces were equipped with numerous short, globular, or irregular microvilli. Apical cytoplasm of adjacent cells did not tightly adhere to each other. Instead, microsulci of 1 to 3 microm in width formed between cells. Cytoplasmic processes from the lateral border spanned the microsulcus and contacted with those from neighboring cells. CONCLUSION: The novel study has proved that the lining epithelium on the inner surface of the nasolabial cyst is columnar epithelium that chiefly consisted of two types of cells: goblet cells and basal cells. Not present were ciliated cells that were essential in the other portion of the respiratory tract. Numerous microvilli, instead of cilia, covered the inner lining of the nasolabial cyst, probably as a result of lacking the stimulation of air in ventilation as that on the other portion of the respiratory tract. The cilia of the epithelium were ill developed.

Journal Watch : Problems of Impacted Dentures - Nwaorgu et al, 2004

1. Reviewers wanted for otolaryngology news journal's watch page. If you are an Otolaryngologist in Africa and will like to be our journal reviewer, please feel free to email orl-mailer@otolaryngologyinafrica.net

2. DODA 2006, capable of advanced hearing measure, and also paediatric hearing assessment is being developed. If you requested for and got a free copy of DODA, you may also look out for this latest version dubbed DODA-i, as well as for an additional page on outcome of hearing assessment using DODA.

Till Next Week,

Biodun

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