Interview with John Leonetti MD, Professor of Otolaryngology, Loyola University Medial Center, Chicago, Illinois
Share:
Part One - Tympanoplasty for Audiologists
Part One - Tympanoplasty for Audiologists
AO/Beck: Good Morning Dr. Leonetti. Thanks for spending some time with me today and thanks for agreeing to provide this tutorial for audiologists on tympanoplasty, cholesteatoma and mastoidectomy.
Leonetti: Hi Dr. Beck, it's a pleasure to speak with you again and I'm happy to participate.
AO/Beck: Thank you. Probably the best place to start is with a working definition of the word tympanoplasty. I've always thought of it as an operation on the middle ear and/or it's contents? Is that about right?
Leonetti: Yes, that'll work, I like to think of it as the repair of the tympanic membrane and it is characterized by the relationship of the repair of the tympanic membrane to the ossicular chain.
The most basic type of tympanoplasty is a type one repair. The type one repair implies a repair of a perforation only. The repair can be an overlay or an underlay technique and it can be done in the office such as a myringoplasty. In a myringoplasty, we freshen the edges of the perforation and lay a paper patch over it. Using that technique, a dry, small perforation can actually heal and it works fine. However, if there is a larger perforation, and it's not likely to be repaired successfully in the office, then the surgical procedure referred to as a type one repair can be done in the operating room under local or general anesthesia and it takes about 30 minutes. Of course, most small perforations heal on their own, and only a very few need surgical repair.
AO/Beck: Very good. Let me go back to the terms overlay versus underlay please. Does overlay mean placing the graft from the external auditory canal side onto the proximal side of the TM, whereas underlay means placing the graft from the medial side, or from within the middle ear to cover the medial side of the TM?
Leonetti: Yes, that's exactly correct.
AO/Beck: OK, great. Let's move on to a type two tympanoplasty please.
Leonetti: A type two tympanoplasty is essentially a repair of the eardrum, with replacement of the incus. The incus is replaced with either a prosthetic ossicle, or an incus interposition, assuming there is enough incus left to be reshaped and reinserted between the stapes and the malleus.
In the case of a type two tympanoplasty, if the patient does not have enough residual incus for us to use, we may use a TORP (total ossicular replacement prosthetic) or a PORP (partial ossicular replacement prosthetic). As you know Doug, TORPs and PORPs are available from many manufacturers, and they come in all sorts of shapes and sizes. Over the last few years, most middle ear prosthetics have been made from hydroxyapetite with some sort of plastic component. The newer prosthesis are made of titanium, and with rare exception, I use titanium across the board at this time.
AO/Beck: OK, so far I'm still with you. Please describe the type three tympanoplasty.
Leonetti: The type three tympanoplasty implies that the grafted tympanic membrane has been placed directly on the head of the stapes so there is no replacement of the missing incus. A type three would have no man-made prosthesis.
AO/Beck: Dr. Leonetti, what is the most common clinical scenario that would lead to a type three tympanoplasty? Would this result from a long term otitis that was necrotic?
Leonetti: Yes, that's right. These operations typically are the result of long term chronic otitis media with an atelectatic tympanic membrane that has retracted so much that the incus has eroded and the tympanic membrane has attached by itself to the head of the stapes.
AO/Beck: And I believe the final tympanolplasty category is the type four?
Leonetti: Yes, the type four is always associated with a canal wall down (CWD) mastoidectomy. So basically, in the type IV, the mastoid has been very much drilled away to eradicate disease, the tympanic membrane graft has been placed directly on the stapes footplate, and there is no stapes superstructure, and no stapes head. The graft is directly on the footplate.
AO/Beck: So then types I, II and III would repair the middle ear and restore hearing, whereas the type IV tympanoplasty would result in a maximal conductive hearing loss?
Leonetti: Yes, that's true of the type IV, if it's left alone. However, sometimes type IV tympanoplasty will be followed up in 6 to 12 months and if the eustachian tube is functioning well and if it is aerating the middle ear space, then we can go back in, dissect the drum off of the stapes footplate, and place a TORP from the stapes footplate to the underside of the tympanic membrane.
AO/Beck: Excellent discussion Dr. Leonetti. Thank you for your time this morning. In the next interview we'll address cholesteatoma and mastoidectomy.
Leonetti: Thank you Doug. I'll look forward to it.
AO/Beck: Good Morning Dr. Leonetti. Thanks for spending some time with me today and thanks for agreeing to provide this tutorial for audiologists on tympanoplasty, cholesteatoma and mastoidectomy.
Leonetti: Hi Dr. Beck, it's a pleasure to speak with you again and I'm happy to participate.
AO/Beck: Thank you. Probably the best place to start is with a working definition of the word tympanoplasty. I've always thought of it as an operation on the middle ear and/or it's contents? Is that about right?
Leonetti: Yes, that'll work, I like to think of it as the repair of the tympanic membrane and it is characterized by the relationship of the repair of the tympanic membrane to the ossicular chain.
The most basic type of tympanoplasty is a type one repair. The type one repair implies a repair of a perforation only. The repair can be an overlay or an underlay technique and it can be done in the office such as a myringoplasty. In a myringoplasty, we freshen the edges of the perforation and lay a paper patch over it. Using that technique, a dry, small perforation can actually heal and it works fine. However, if there is a larger perforation, and it's not likely to be repaired successfully in the office, then the surgical procedure referred to as a type one repair can be done in the operating room under local or general anesthesia and it takes about 30 minutes. Of course, most small perforations heal on their own, and only a very few need surgical repair.
AO/Beck: Very good. Let me go back to the terms overlay versus underlay please. Does overlay mean placing the graft from the external auditory canal side onto the proximal side of the TM, whereas underlay means placing the graft from the medial side, or from within the middle ear to cover the medial side of the TM?
Leonetti: Yes, that's exactly correct.
AO/Beck: OK, great. Let's move on to a type two tympanoplasty please.
Leonetti: A type two tympanoplasty is essentially a repair of the eardrum, with replacement of the incus. The incus is replaced with either a prosthetic ossicle, or an incus interposition, assuming there is enough incus left to be reshaped and reinserted between the stapes and the malleus.
In the case of a type two tympanoplasty, if the patient does not have enough residual incus for us to use, we may use a TORP (total ossicular replacement prosthetic) or a PORP (partial ossicular replacement prosthetic). As you know Doug, TORPs and PORPs are available from many manufacturers, and they come in all sorts of shapes and sizes. Over the last few years, most middle ear prosthetics have been made from hydroxyapetite with some sort of plastic component. The newer prosthesis are made of titanium, and with rare exception, I use titanium across the board at this time.
AO/Beck: OK, so far I'm still with you. Please describe the type three tympanoplasty.
Leonetti: The type three tympanoplasty implies that the grafted tympanic membrane has been placed directly on the head of the stapes so there is no replacement of the missing incus. A type three would have no man-made prosthesis.
AO/Beck: Dr. Leonetti, what is the most common clinical scenario that would lead to a type three tympanoplasty? Would this result from a long term otitis that was necrotic?
Leonetti: Yes, that's right. These operations typically are the result of long term chronic otitis media with an atelectatic tympanic membrane that has retracted so much that the incus has eroded and the tympanic membrane has attached by itself to the head of the stapes.
AO/Beck: And I believe the final tympanolplasty category is the type four?
Leonetti: Yes, the type four is always associated with a canal wall down (CWD) mastoidectomy. So basically, in the type IV, the mastoid has been very much drilled away to eradicate disease, the tympanic membrane graft has been placed directly on the stapes footplate, and there is no stapes superstructure, and no stapes head. The graft is directly on the footplate.
AO/Beck: So then types I, II and III would repair the middle ear and restore hearing, whereas the type IV tympanoplasty would result in a maximal conductive hearing loss?
Leonetti: Yes, that's true of the type IV, if it's left alone. However, sometimes type IV tympanoplasty will be followed up in 6 to 12 months and if the eustachian tube is functioning well and if it is aerating the middle ear space, then we can go back in, dissect the drum off of the stapes footplate, and place a TORP from the stapes footplate to the underside of the tympanic membrane.
AO/Beck: Excellent discussion Dr. Leonetti. Thank you for your time this morning. In the next interview we'll address cholesteatoma and mastoidectomy.
Leonetti: Thank you Doug. I'll look forward to it.
