Patients and methods
otosclerosis
MIDDLE EAR, EXTERNAL EAR, DEHISCENCE, OTOSCLEROSIS
This study was a prospective single blinded randomized clinical study carried out between September 2021 and September 2022. Approval from Institutional ethics committee was obtained (code: MS.21.11.1758). The study was conducted among 60 patients with clinical evidence of otosclerosis who were randomly divided into two equal groups (each containing 30 patients) using computer generated block randomization. Patients in group 1 underwent endoscopic classic stapedotomy while patients in group 2; on the other hand; underwent endoscopic reversal stapedotomy.All involved patients had clinically evidenced otosclerosis including gradual progressive diminution of hearing with intact tympanic membrane, an audiogram showing ABG > 20 dB at the frequencies of 0.5, 1, 2 and 3 kHz together with absent stapedial reflex. Revision cases, cases with obliterative type of otosclerosis, and cases with facial nerve dehiscence were all excluded. Since narrow footplate is a contraindication for reversal stapedotomy, we also excluded all cases with narrow footplate to make the whole patients amenable for both classic and reversal stapedotomies. We defined narrow footplate as a footplate that could not accommodate a 0.7 mm manual perforator.A 0° endoscope, 17 cm length and 4 mm diameter (Karl Storz, Germany) which was coupled to a high-definition (HD) camera head connected with a monitor (Karl Storz, Germany) were used. All surgeries were performed under local anesthesia (2% lidocaine with 1:50,000 epinephrine). The surgery began with 4 quadrant injection of the local anesthetic solution. Incision of the skin of the external ear canal was performed followed by tympano-meatal flap elevation towards the tympanic annulus. Entry to the middle ear was then carried out by raising of the tympanic annulus out of its sulcus. Curettage of the posterosuperior canal wall was carried out till the following structures were fully exposed: the stapes footplate, the facial nerve, the stapedial tendon and the pyramid. The ossicular chain mobility was then assessed to confirm the true diagnosis of otosclerosis. Measurement of the size of footplate was then done by using a 0.7 mm manual perforator. Cases where the footplate could not accommodate the 0.7 mm perforator were excluded because this would be a narrow footplate which is a contraindication for reversal stapedotomy.