Yamilet Tirado, M.D.
July 19, 2007
Disclaimer: The information contained within the Grand Rounds Archive is intended for use by physicians and other health care professionals. These documents were prepared by resident physicians for presentation and discussion at a conference held at Baylor College of Medicine in Houston, Texas. No warranties, either express or implied, are made with respect to accuracy, completeness or timeliness of this material. This material does not necessarily reflect the current or past opinions of the faculty of Baylor College of Medicine and should not be used as a basis for diagnosis or treatment, and is not a substitute for professional consultation and/or peer-reviewed medical literature.
I will be talking about a cartilage tympanoplasty technique. I will start our discussion, as always, with a case presentation, then go over the history of cartilage tympanoplasty, describe some of the general concepts of this procedure, as well as the techniques for reconstruction, and the indications. I will then discuss the postoperative care of patients undergoing cartilage tympanoplasty and the postoperative results that can be expected and, finally, our conclusions.
I.D. is a 13-year-old boy with history of recurrent episodes of otitis media and Eustachian tube dysfunction. He has had tympanostomy tube placement three times, and underwent adenoidectomy. His last tympanostomy tube placement was approximately two years ago. Even though he has not had any recent ear infection or drainage from the ears, he has had a persistent right ear effusion with bilateral hearing loss that markedly has markedly affected his ability to follow along in school. He has been treated with oral antibiotics and nasal sprays without improvement.
On physical examination, the external ear and canal were normal bilaterally. The right tympanic membrane was significant for posterior atelectasis and serous otitis media. The left ear had significant atelectasis along with cholesteatoma formation in the posterior pars tensa. The incudostapedial joint was suspected to be eroded. I.D. was unable to autoinsufflate his tympanic membranes and neither one was mobile to pneumatic otoscopy. The tuning fork test suggested bilateral conductive hearing loss. The rest of his physical exam was unremarkable.
An audiogram was obtained that showed the speech recognition of 40 dB in the right ear and 50dB in the left ear, with bilateral type B tympanograms. At this point, the decision was made to proceed with the surgical intervention to improve his bilateral conductive hearing loss. Intraoperatively, he was found to have right ear atelectasis with mucoid middle ear effusion and underwent right tympanostomy tube placement. Left ear pas tensa cholesteatoma extending into the mesotympanum, without any erosion of the ossicular chain was found in the left ear. The cholesteatoma sac was removed in its entirety and the atelectatic portion of the tympanic membrane was excised. The tympanic membrane was reconstructed with cartilage using the cartilage/perichondrium island technique with tragal cartilage.
Postoperatively, he did very well, and was able to notice some improvement in his hearing during his first post operative visit. During his second postoperative visit, the residual packing was removed, and the tympanic membrane graft was noted to be hearing well. Autoinsulfation was started, and an audiogram showed resolution of conductive hearing loss in the right ear with a persistent mild conductive hearing loss in the left ear. A six-month follow-up audiogram showed some hearing improvement in the left ear with a speech recognition threshold of 23dB. However, a type C tympanogram was obtained in his left ear, suggesting a persistence of his Eustachian tube dysfunction.
The use of cartilage in middle ear surgery is not a new concept, but the last decade has shown a renewed interest in this material as an alternative to more traditional grafting materials for TM reconstruction. The use of cartilage in the middle ear was first introduced in middle ear surgery in 1958 by Jansen. Heerman in 1962 first introduced the cartilage palisade technique and, a year later, Salen and Jansen first reported its benefits on reconstruction of the tympanic membrane. In 1994, Poe and Gadre reported successful outcomes when used to reconstruct the pars flacida. During this century, its uses have expanded significantly. For example, a study by Dr. Vrabec showed significant benefit when applying it to ossiculoplasty to prevent extrusion of the prosthesis. Just recently, Dornhoffer validated its indications and reinforced its significance on hearing improvement.
Cartilage has become an alternative to more traditional grafting materials for the tympanic membrane reconstruction. Vein graft was very popular for many years, but has been replaced by temporalis fascia. Perichondrium and dura matter have also being used. Currently temporalis fascia and perichondrium are most commonly materials used. Cartilage has shown itself to be a novel material with high success rate in more challenging cases such as retraction pockets, recurrent perforation, atelectasis, cholesteatoma and ossicular chain reconstruction.
To date, temporalis fascia and perichondrium remain the most commonly employed materials for closure of tympanic membrane perforations. The success rate in TM reconstruction with these materials approaches 90%. In certain situations, such as the atelectatic ear, cholesteatoma, and revision tympanoplasty, the results with these materials have not been as gratifying. Fascia and perichondrium have been shown to undergo atrophy and subsequent failure in the postoperative period. This has led to the use of cartilage, which is a less compliant, more rigid material that resists resorption and retraction. It has also been shown by different studies that it is well tolerated by the middle ear and hearing results have been comparable with those of fascia and perichondrium.
There are different types of cartilage in the body including hyaline, elastic and fibrocartilage. The type used in cartilage tympanoplasty is the elastic type, which can be located in the external ear, the external auditory canal and the Eustachian tube. In the external ear, the cartilage useful for tympanoplasties can be taken from the tragus, the concha and the fossa triangularis. Histologically, it is composed of the matrix, the lacunae where the chondrocytes are found, and elastic fibers that are rich in the protein elastin that provide flexibility and resilience to the matrix, giving in the “memory” that characterize it. When the cartilage is used as a material graft for tympanoplasty, it survives by diffusion and inhibition and eventually becomes well incorporated in the tympanic membrane. Some studies have evaluated the longevity of cartilage in the middle ear and histologic evaluation of cartilage graft at one year have shown that although the matrix appears intact, the condrocyte degenerate, leaving behind empty lacunae. For example, this picture shows the cartilage at one month after the reconstruction, and the chondrocytes are degenerating within the lacunae and this one, at about one year, shows complete degeneration of chondrocytes with empty lacunae.
One of the concerns regarding the use of cartilage tympanoplasty is the effect that it has on hearing. When it is used to reconstruct the tympanic membrane, it increases the acoustic impedance of the tympanic membrane because of its increased mass and stiffness. Zahnert in 2000 developed an elegant study using the laser Doppler interferometer and cadaver cartilage to determine the ideal acoustic thickness of cartilage. He found that this thickness was 0.5 mm. This is a graphic from his study that analyzed the sound conduction properties of different cartilage thicknesses for different frequencies. The conduction of these cartilages was compared with that of the tympanic membrane, which follows the thick black line. Only the thinnest cartilage, the 0.27mm, which was not necessarily the most functional, showed a frequency response similar to that of the tympanic membrane. The 0.5mm cartilage and the uncut cartilage showed a 5dB and 25dB los respectively when compared with the tympanic membrane. He also found that for thicker cartilage, the conduction los was higher in the lower frequencies.
Some authors still use full thickness cartilage of 0.7mm to1 mm because of difficulty trimming using it with a #15 blade and because, when thinned, the graft curls in an unacceptable fashion making its placement difficult and less precise. Nowadays, these are more precise ways to cut the cartilage as, for example, this cartilage knife that can obtain a desirable thickness as thin as 0.1mm, depending on the blade that is used. The manufacturer recommends trimming the cartilage to a thickness of 0.5 mm.
There are multiple different ways to perform cartilage tympanoplasty and I will discuss in detail some of the most important ones. The perichondrium/cartilage island flap is a tympanic membrane reconstruction using a large piece of cartilage that spans an affected area and acts as a full thickness graft. Tragal cartilage is usually used because it is thin, flat and is available in sufficient quantity to permit reconstruction. It is most useful in cases of atelectasis, high risk perforation, and in ossiculoplasty in cases where the malleus is absent. It prevents the prosthesis on touching the graft in the lateral aspect, preventing extrusion. . The technique involves harvesting the cartilage from the tragus with the attached perichondrium. The perichondrium is dissected off from one side, and a perichondrium/cartilage island flap is created. A strip of cartilage 2mm in width is removed vertically from the center to accommodate the malleus handle. The middle ear is packed with Gelfoam. The graft is placed in an underlay fashion with the cartilage side placed toward the promontory and the perichondrium placed adjacent to the tympanic membrane remnant and the posterior ear canal. Gelfoam is placed lateral to the reconstructed tympanic membrane, and antibiotic ointment is placed. This is a postoperative picture of an ear reconstructed with this technique.
Another useful technique is the palisade technique, which involves reconstruction with palisade-shaped cartilage pieces to span areas of perforation, prosthesis and to reconstruct scutal defects. By reducing the cartilage thickness, as in this technique, the acoustic impedance may decrease, leading to an improvement of acoustic transfer. Tragal and cymba cartilage can be used depending on whether an endaural or postauricular approach was used. The palisade technique is most commonly used in high risk perforation and ossiculoplasty in cases where the malleus is present, and cholesteatoma.
This is a summary of some of the studies related to the palisade cartilage technique and its success rate. All these studies were retrospective ones involving more that 50 cases each. While the first two studies evaluate multiple middle ear and tympanic membrane pathologies, the third study concentrated on tympanic membrane perforations alone in the setting of a healthy middle ear. The first study was performed by the Mirko Tos group and included 61 cases cholesteatoma. That were divided in pars tensa cholesteatoma and sinus cholesteatoma and they compared the cartilage palisade technique with the fascia technique. The success rate was higher in the cartilage tympanoplasty group and all postoperative re-perforations occurred in the fascia group. The second study by Neumman was very similar to Tos group in evaluating 84 cases with different ear pathologies but these included atelectasis, cholesteatoma and subtotal perforation. However, no comparison was made with fascia tympanoplasty but the success rate for the cartilage tympanoplasty was nearly 100%. The last study by Kazikdas was different from the previous two as it only included identical cases with subtotal perforations and normal middle ear disease. The cartilage and fascia techniques were compared as well and the cartilage tympanoplasty technique showed higher success rate. However, this study was unable to demonstrate a statistically significant difference between the study groups secondary to low number of cases.
Another technique reserved for more selected cases is the cartilage-shield/T-tube tympanoplasty where cartilage is placed medial to the malleus manubrium. In this technique a single large piece of cartilage graft is placed and a pressure equalization tube is inserted through the cartilage intraoperatively to ventilate the middle ear and eliminate any recurrent effusion in the postoperative period. This is useful in cases of total perforations, atelectasis and previously failed tympanoplasties where effusion is expected postoperatively.
The butterfly inlay graft is a more challenging technique used to close small tympanic membrane perforations. In this technique, the tympanic membrane is reconstructed with circumferentially incised edges of cartilage curled apart like the wings of a butterfly, enabling tight anchorage of the graft to the rims of the perforation. Some benefits of this technique include the use of an endaural or transcanal approach using tragal cartilage, and no need for packing the ear canal. This is a picture showing an inferior perforation. The cartilage is shown here and the margins have been split into to lips that hug the rims of the tympanic membrane remnant. This is a picture of the tympanic membrane after the cartilage is placed.
All the techniques discussed so far can be expanded. For example, it has been shown that the butterfly technique can also be applied for large perforations of the tympanic membrane. In a study by Ghanem and Eavey, this technique was used in 90 patients with large tympanic membrane perforations. They showed that the technique was useful and the success rate exceeded 90%, and the hearing results improved or remained stable. The cartilage is depicted here in gray and the margin of the cartilage has been split into two lips that are hugging the bony prominence of the annulus. This is, again, showing the cartilage margin split into two lips and this is when it anchors the tympanic membrane.
So far, I have discussed some of the techniques used for cartilage tympanoplasty along with some of the indications for each technique. However, I would like to go into a much more detailed explanation on each of the indications. Cartilage tympanoplasty has been proven to be successful in cases of retraction pockets, recurrent perforations, ossicular chain reconstruction, atelectasis of the TM, cholesteatoma and Eustachian tube dysfunction. In cases of high risk or recurrent perforations, tympanoplasty failure rates increase in association with revision surgery, anterior perforations, chronic Eustachian tube dysfunction, perforation draining at the time of the surgery and large perforations. This is a very controversial situation in the pediatric population in regards to timing of repair: whether or not it should be repaired during the otitis prone years and in the setting of chronic Eustachian tube dysfunction. A general approach to the repair of a TM perforation in the pediatric population takes into consideration the status of the contralateral ear. If the contralateral ear is normal, a tympanoplasty is considered at age 4. However, if it is abnormal, adenoidectomy is considered first and tympanoplasty is deferred to later years. However, recent studies have shown that results using cartilage tympanoplasty in the pediatric population have been successful and the hearing results are no different from results using perichondrium or fascia. The success rate in this population using the traditional fascia approach ranges from 35 to 94%. In a prospective study performed by El-Hennawi, a pediatric population of 30 patients with tympanic membrane perforation was studied after cartilage tympanoplasty was performed and a success rate was achieved in 86% of the cases regardless of the site of perforation or the associated middle ear pathology. However, he found that there was a higher success rate in patients older than 10 years. For this reason, he recommended that delaying surgical intervention to an older age was necessary to increase the success rate of this procedure.
Another indication for cartilage tympanyplasty is ossiculoplasty. Something to have in mind is that any condition that may affect the integrity of your graft may ultimately affect your ossiculoplasty leading to extrusion. For this reason, ossiculoplasty is usually performed in conjunction with reconstruction of the TM to prevent this. Prosthesis extrusion is defined as breakdown of the tympanic membrane resulting in exposure of the implant. An early extrusion occurs less than 2 months and a late extrusion occurs after more than 6 months. Dr. Vrabec in 2002 evaluated 221 cases of fascia tympanoplasty with ossiculoplasty and found that the incidence of early prosthesis extrusion was 8% and that of late extrusion was 14%. In the cases of late extrusion, he found a higher incidence of postoperative atelectasis, recurrent otitis media and myringitis but was unable to identify any variable that predicted this situation. For this reason, he recommended performing a cartilage tympanoplasty at the time of total ossiculoplasty to prevent prosthesis extrusion.
The technique used for cartilage reconstruction with ossiculoplasty depends on the presence or absence of the malleus manubrium. In the malleus present situation, the palisade technique is very effective and also provides good acoustic benefit. The malleus-absent situation represents one of the most challenging situations for cartilage tympanoplasty and ossicular reconstruction. The perichondrium/cartilage island flap is used in these cases to prevent the prosthesis touching the tympanic graft and preventing extrusion. In these cases, the anterior portion of the cartilage is held securely in place while the posterior half is folded out to expose the trailing edge of the anterior piece of cartilage, which acts, in effect, as a neo-malleus. The distance between the stapes footplate or suprastructure and this trailing edge is measured and the prosthesis is cut to the appropriate length. The posterior portion is unfolded. The nice thing about folding the prosthesis in half is that you can visualize the prosthesis and have precise placement.
In patients with chronic Eustachian tube dysfunction, the membrane can collapse and become atrophic over time. The management of the atelectatic ear remains controversial, and the indications for surgical intervention have been discussed in previous publications. Cartilage tympanoplasty using the perichondrium/cartilage island flap is useful for reconstruction of the entire TM. After elevation of the atrophic TM off the promontory, it is tempting to insert the cartilage medial to the intact TM. However, it is important to remove at least a portion of the atrophic TM anterior and posterior to the malleus to ensure that the cartilage flap is well incorporated.
In fact, the atelectatic ear represents the first and most well described situation in which cartilage techniques have been utilized. As we can observe here, the atelectatic membrane is entirely elevated from the malleus and the atelectatic portions are removed. The cartilage is harvested and processed. The middle ear is packed with gelfoam and the cartilage is placed lateral to the malleus with the perichondrium side towards the ear canal. Once this is performed, the TM is placed back in position and you can notice that the atelectatic portion has been entirely removed.
Cholesteatoma represents one of the most controversial but important pathologic conditions in which cartilage is used. The primary purpose of cholesteatoma surgery is to eradicate disease and provide a safe, hearing ear. The magnitude of the controversy regarding optimal surgical care is beyond the scope of this presentation, but cartilage should arguably be involved in each technique. The palisade technique has been very useful in the cholesteatoma setting as it gives the opportunity, if needed, to perform an ossiculoplasty in a precise way. Also, some authors prefer to leave the anterior portion of the TM without cartilage for surveillance and possible tube placement, if necessary, in the postoperative period. However, cartilage placement in the posterior aspect of the TM can certainly delay a recurrence. but, in most series, cholesteatoma will recur in the anterior portion of the TM and it can be suspected in the setting of a recurrence in conductive hearing loss. After my review of literature, I found that the recurrence rate for cholesteatoma after cartilage tympanoplasty is less than 10%. And if we compare this rate with cholesteatoma recurrence rate overall in children, we can appreciate that is much lower than rates previously reported in the literature which ranges from 10-46%.
Anderson performed a comparative study of children with sinus and pars tensa cholesteatoma that underwent cartilage vs. fascia tympanoplasty, in regards to cholesteatoma recurrence, postoperative TM retraction or perforation and hearing results.He found that there was more recurrence of retraction pockets in cases of fascia tympanoplasty. And, in regards to hearing, he found that the cartilage group had better hearing results overtime. When the groups were evaluated separately by disease and type of repair, the sinus cholesteatoma group repaired with cartilage had better hearing results over time. These results showed that the palisade technique may have been superior to fascia in preventing retraction pockets as well as providing good and long term hearing results.
A patient undergoing cartilage tympanoplasty is evaluated approximately 1 to 2 weeks after the procedure. At that time the packing material is partially removed and antibiotic/steroid containing drops are started. Two weeks postoperatively, the Valsalva maneuver is started. An audiogram is performed about 6-8 weeks after surgery.If the hearing result is good and the TM is clear, the ear is examined at 6 months and again at 1 year from the date of surgery.
However, during the postoperative period, the patient can develop some complications such as effusion, as well as residual or recurrent cholesteatoma. An effusion can be detected by physical exam or suspected with a new onset of hearing loss, and sometimes a CT temporal bone has to be ordered for further evaluation. For example, this is a CT temporal bone in the postoperative period that does not show any evidence of effusion, but at least you can appreciate clearly how the cartilage graft should look. Finally, the patient is started on nasal steroids, Valsalva maneuver or Otovent in the pediatric population. If the effusion persists longer than 3 months, a T-tube is considered.On the other hand, the patient can develop recurrence of their primary disease, which can be detected by routine evaluation or the surgeon can plan a second look staged surgery for surveillance.
Finally, I would like to discuss in detail the hearing results that can be obtained from cartilage tympanoplasty. Kiraliz in 2005 took this issue into consideration and compared the hearing results of the cartilage to that of fascia in identical cases. He evaluated only patients with subtotal perforation with intact ossicular chain and normal middle ear mucosa. Statistical analysis of the preoperative conduction thresholds between the cartilage and the fascia group showed that both groups were statistically identical. He was able to demonstrate that the overall hearing gain was about the same in both groups.
I will like to end this discussion by presenting the most comprehensive study on cartilage tympanoplasty. This study, by Dornhoffer as his Triological Society thesis, included an evaluation on indications and hearing results in patients who underwent cartilage tympanoplasty. He retrospectively analyzed the anatomical and functional results in more than a 1000 cases and ended up with 636 cases available for outcome analysis. As you can see, he had a wide ranging population that overall showed a significant hearing improvement. He dividing his population according to the underlying disease and evaluated the hearing results as well as their complications. As you can see here, his cholesteatoma population was approximately 35% of his total population and overall had a significant hearing improvement postoperatively with a low percentage of complications. Patients with tympanic membrane perforation, who constituted 34% of the total population showed overall a significant hearing improvement postoperatively with a low percentage of complications. Atelectasis constituted 15% of the population and, again, a significant hearing improvement was seen postoperatively along with a low percentage of complications. He was able to conclude that cartilage tympanoplasty achieves good anatomical and audiologic results when pathology and status of the ossicular chain dictate the technique used. He also demonstrated hearing improvement in each of the groups studied, validating its indication for these certain groups of patients.
Back to my case presentation, I would like to show his preoperative and postoperative audiograms and reinforce that we obtained significant and appropriate hearing results considering that this patient had the underlying problem of chronic ear disease. Eustachian tube dysfunction is an important problem with all recurrent ear disease. In fact, hearing loss could be caused by adhesions of the tympanic membrane to the promontory as well as the ossicular chain, and this scar formation is notoriously difficult to treat.
In conclusion, the use of cartilage is experiencing a renaissance in ear surgery because it appears to offer an extremely reliable method for reconstruction of the tympanic membrane in cases of advanced middle ear pathology and Eustachian tube dysfunction.Cartilage is particularly useful for the atelectatic ear, cholesteatoma, high risk perforation and for reinforcement of the tympanic membrane in conjunction with ossiculoplasty.Hearing improvement can be experienced with the use of cartilage regarding the underlying pathology. Excellent clinical and experimental evidence exists to justify the use of cartilage as a grafting material in pediatric tympanoplasty. Cartilage tympanoplasty provides a tympanic membrane repair with greater structural stability and strength than traditional graft materials in many patients with challenging middle ear environments.
I.D. is a 13 year-old boy with a history of recurrent episodes of otitis media. He has had tympanostomy tube placement three times and underwent adenoidectomy. His last tympanostomy tube placement was approximately 2 years ago. He has not had any recent ear infection or drainage from the ears; however, he has a persistent right ear effusion and bilateral hearing loss that has markedly affected his ability to follow along in school. He has been treated with oral antibiotics and nasal sprays without improvement.
On physical examination, the external ear and canal were normal bilaterally. The right tympanic membrane was significant for posterior atelectasis and serous otitis media. The left ear had significant atelectasis along with cholesteatoma formation in the posterior pars tensa. The incudostapedial joint was suspected to be eroded. I.D. was unable to autoinsufflate his tympanic membranes and neither one was mobile to pneumatic otoscopy. Tuning fork test suggested bilateral conductive hearing loss. The rest of his physical exam was unremarkable.
An audiogram was obtained that showed a speech recognition threshold of 40 dB in the right ear and 50dB in the left ear, with bilateral type B tympanograms. Decision was made to proceed with surgical intervention to improve his bilateral conductive hearing loss.
I.D. underwent right tympanostomy tube placement and left removal of cholesteatoma with cartilage tympanoplasty reconstruction. Intraoperatively, he was found to have right ear atelectasis with mucoid middle ear effusion along with left ear pars tensa cholesteatoma, without any erosion of the ossicular chain. The cholesteatoma was removed in its entirety and the atelectatic portion of the tympanic membrane was excised. The tympanic membrane was reconstructed with cartilage using the cartilage/perichondrium island technique with tragal cartilage.
Postoperatively, I.D. did very well and was able to notice some improvement in his hearing during his first post op visit. The right tube was found to be patent and the middle ear was well aerated. The left tragal and postauricular incisions were intact and the packing was in place. Partial removal of packing was performed and dry ear precaution with continuation of ear drops was recommended. Two weeks later, during his second postoperative visit, the residual packing was removed, and the tympanic membrane graft was noted to be healing well. Autoinsuflation was started, and an audiogram was performed 6 weeks after his surgery. The audiogram showed resolution of conductive hearing loss in the right ear with a persistent mild conductive hearing loss in the left ear.
I.D. continued to have dry ears postoperatively, and a 6-month follow up audiogram showed some improvement in his hearing with a speech recognition threshold of 25dB. However, a type C tympanogram was obtained in his left ear, suggesting a recurrence of his Eustachian tube dysfunction. He has been followed up on a regular basis with Dr. Vrabec, with no new changes on his physical exam or hearing. His performance at school has improved significantly, and preferential seating along with a hearing aid have been recommended. During his last visit, a CT Temporal bone was ordered for cholesteatoma surveillance, which, unfortunately, was not available at the time of this presentation.
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