Autologous Fascia-Bone-Fascia Technique for Tegmen Repair

Objective To describe a novel and effective means of repairing middle ear cerebrospinal fluid (CSF) leaks due to tegmen defects, via a middle fossa approach using autologous fascia-bone-fascia technique, with concomitant repair of tympanic membrane perforation with paper patch.

Background Risks posed by spontaneous CSF otorrhea include a predisposition to meningitis, persistent otorrhea, as well as conductive hearing loss. Methods of repair include approaches via the middle fossa as well as the mastoid cavity. Often, patients have received tympanostomy tubes for their effusion, and subsequently, have a potential route of infectious spread into the middle ear space, increasing the risk of intracranial infections. As a result, repair is often desired and performed to close the CSF leak by repairing the tegmen defects.

Methods The patient is brought to the operating room and laid supine with the head turned 90 degrees opposite the side of repair. Placement of a lumbar drain is not required. A curvilinear incision based in the pretragal region is carried superiorly above the ear. Wide exposure of the temporalis fascia allows for a large, 3 × 3 cm harvest of fascia. A 3 × 4 cm temporal craniotomy is drilled with a combination of cutting and diamond burrs, and the bone flap is set aside. After elevating the temporal lobe dura and exposing the tegmen defects ([Fig. 1]), a portion of the inner cortex of the bone flap is harvested using a sagittal saw. The bone graft is contoured to the middle fossa floor with a diamond bur. Single or multiple defects are then covered with a piece of the fascia graft ([Fig. 2]), followed by the shaped inner cortex bone ([Fig. 3]), and an additional layer of fascia ([Fig. 4]). For areas of thinned dura, a small piece of bilayer collagen graft may be placed. The bone flap is returned and secured with three titanium plates on the anterior, posterior, and superior surfaces. Attention is turned to the ear canal and any fluid in the middle ear is evacuated, followed by removal of the tympanostomy tube, if present. The resulting tympanic membrane perforation is repaired with a paper patch and Gelfoam, and the patient is admitted to the stepdown surgical unit for observation.

Results Although alluded to in the literature, this is the first step-by-step description of autologous repair of tegmen defects via the middle fossa approach utilizing fascia-bone-fascia layering. Patients are discharged on postoperative day 2. Repair of tegmen defects, coupled with removal of tympanostomy tube and simultaneous closure of the perforation, results in improvement of conductive hearing deficits.

Conclusion The repair of tegmen defects via the middle fossa approach with fascia-bone-fascia, with simultaneous tympanic membrane repair, is a safe and effective means of patient management to alleviate hearing loss, quell CSF otorrhea, and reducing the risk of developing meningitis.

Fig. 1 Defect.

Fig. 2 Fascia layer 1.

Fig. 3 Bone graft.

Fig. 4 Fascia layer 2.

No conflict of interest has been declared by the author(s).