Variations In Bone Conduction Thresholds Of Patients With Conductive Hearing Loss After Surgical Treatment Of Chronic Middle Ear Disease
Objectives: To evaluate variations in bone conduction thresholds as a result of surgical treatment of chronic middle ear disease.
Methods: The present study is a quasi-experimental study which was conducted from 1st February 2016 to 31st July, 2016 at ENT department of Al-Nafees Medical College Hospital Islamabad. It involved collection of pre and post treatment audiometric data from the hospital records of 153 patients which were surgically treated for conductive hearing loss due to chronic middle ear disease. The patient were divided into five groups according to the type of middle ear disease. The mean pre-treatment bone conduction thresholds at frequencies of 250, 500, 1000, 2000 and 4000 Htz were compared with the respective mean post-treatment bone conduction thresholds as a whole and within each group. The difference of means were calculated and statistically evaluated by paired sample t test. A change of >10dB in pre and post-treatment bone conduction was considered significant.
Results: Among those 153 patients who were included in the study, 57 (37.5%) were male and 95 (62.5 %) were female. Male to female ratio was 1:1.6. The patient age range was from 10 to 61 years with a mean age of 24.46 years (SD 10.85). The results showed that there was no significant change (p >0.05) in bone conduction thresholds in 118 (77.1%) patients. A total of 15 (9.8%) patients showed significant (i.e., >10dB) improvement in pre and post-treatment bone conduction thresholds whereas 20 (13.1%) showed significant deterioration (i.e.,>10dB). Maximum mean improvement of bone conduction thresholds (11.40 dB) was observed in group 2 while group 3 showed maximum mean deterioration (9.56 dB).
Conclusion: The study concluded that there is no significant variation bone conduction thresholds in majority of the cases of chronic middle ear disease as a result of surgical treatment.
Key words: Bone conduction thresholds, deafness, otitis media