Müge AKMANSU, Ahmet URAL, Yusuf K. KEMALOĞLU, Yıldırım A. BAYAZIT, Bülent GÜNDÜZ, Diclehan ÜNSAL, Metin YILMAZ

Evaluation of the cochlear functions with otoacoustic emission in patients irradiated for nasopharyngeal

Amaç: Çalışmanın amacı nazofarenks karsinomları tedavisinde uygulanan radyoterapinin orta ve iç kulak fonksiyonları üzerine etkisini araştırmaktı. Metod: Nazofarenks kanseri nedeniyle radyoterapi planlanan 33 hastanın 66 kulağı çalışmaya alındı. Çalışmaya alınma kriterleri şunlardı; normal otoskopik muayene bulguları ve timpanogram; saf ses odyometrisinde iletim tipi işitme kaybı olmaması; ototoksisite veya geçirilmiş kulak cerrahisi hikayesi olmaması. Takip sürecinde efüzyonlu otitis media geçiren hastalar çalışma dışı bırakıldı. Hastalara saf ses ve konuşma odyometrisi, timpano-metri ve otoakustik emisyon testi uygulandı. Her hastaya Co-60 (Theratron-780 Canada) cihazı kullanılarak toplam 7000 cGy radyoterapi uygulandı. Bulgular: Dokuz aylık takip süresinde, orta kulakta efüzyon gelişmesi nedeniyle hastaların %63.6'sı çalışma dışı bırakıldı. Hastaların radyoterapi öncesi 16.1 dB olan sas ses ortalamaları RT sonrası 9. ayda 20 dB olarak bulunmuştur (p>0.05). RT öncesi ve sonrası frekans spesifik saf ses ortalamaları arasında anlamlı fark bulunamamıştır(p>0.05). Çalışma süresince elde edilen TEOAE değerleri arasında anlamlı fark bulunamamıştır (p>0.05). DPOAE sonuçlarında ise 2 Hz frekansında başlangıç ve 9.ay değerleri dışında anlamlı fark bulunamamıştır(p=0.03). Sonuç: Nazofarenks kanserli olgularda radyoterapi sonrası kısa dönemde kohlea hasarı oluşabilir. Özellikle kohleanın orta bölgesi (2 Hz ) subklinik düzeyde, işitme kaybı şikayetine neden olmaksızın, odiometrik olarak tespit edilebilecek şekilde hasar görebilir. Nazofarenks kanserinde radyoterapinin iç kulağa etkisi uygulanan protokellere göre değişkenlik gösterebilmektedir.

Nazofarengeal karsinoma için radyoterapi almış hastalarda kohlear fonksiyonların otoakustik emisyon ile değerlendirilmesi

Objective: Our purpose was to find out effect of radiation therapy applied for nasopahyngeal carcinoma on the middle and inner ear functions. Methods: Sixty-six cars of 33 patients who were scheduled for radiation therapy for nasopharyngeal carcinoma were included in the study. The inclusion criteria were a normal otoscopic examination and tympanogram, a lack of conductive deafness on pure tone audiometry, and a lack of a history of previous otologic surgery or ototoxicity. Patients who had middle ear effusion in the follow up were excluded. Pure tone and speech audiometry, tympanometry and otoacoustic emission (OAE) testing were performed. Each patient was irradiated with a total dose of 7000 cGy. Co-60 (Theratron-780 Canada) was used in the radiotherapy, and a total of 7000 cGy was given. Results: In the 9-month follow up, 63.6% of the patients were excluded from the calculations due to the development of middle ear effusion. The PTAs of bone conduction were 16.1 dB and 20 dB before and 9 months after radiotherapy, respectively (p>0.05). The frequency specific pure tone results obtained before and 9 months after radiotherapy were not significantly different (p>0.05). The results of TEOAE testing during the follow up were not significantly different (p>0.05). There was no significant change in the DPOAE results (p>0.05) except for in the 2 Hz frequency region, where a significant amplitude reduction was observed in the 9th month compared to the initial recording (p=0.03). Conclusion: Cochlear damage can occur in the short term after radiation treatment for nasopharyngeal carcinoma. This damage, which occurs in the middle portion (2 kHz region) of the cochlea, is at subclinical level and does not lead to a hearing loss detectable by audiometry. The impact of radiation therapy on the inner ear may vary, depending on the application of different radiotherapy protocols in nasopharyngeal carcinoma.

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