Abstract
Cartilage has shown to be a promising graft material to close tympanic membrane perforations. However, due to its rigid quality, doubts are raised regarding its sound conduction properties. It has been suggested that acoustic benefit may be obtained by thinning the cartilage. We describe our innovative method for harvesting tragal cartilage from the same endaural incision and also describe preparation of the graft by slicing it. We present our 3-year experience of shield cartilage type 1 tympanoplasty using sliced tragal cartilage–perichondrium composite graft.
Aim
The aim of this study was to prove the success rate of our technique of shield cartilage tympanoplasty using sliced tragal cartilage graft in terms of functional and anatomic results.
Study design
Retrospective analysis of type 1 cartilage tympanoplasties using sliced tragal cartilage was carried out in MIMER Medical College and Sushrut ENT Hospital during May 2005 to January 2008 with a minimum follow-up of 2 years.
Method and materials
A total of 223 ears were operated by our technique.
Results
The overall success rate of our technique was 98.20% in terms of perforation closure and air bone gap closure within 7.06 ± 3.39 dB. The success rates in the various age group are as follows: 11 to 20 years, 97.67%; 21 to 40 years, 99.12%; and 41 to 60 years, 96.96%.
Conclusion
Our technique of type 1 cartilage tympanoplasty achieves good anatomic and functional results.
1
Introduction
Temporalis fascia remains the most frequently used graft material with closure of the tympanic membrane in 70% to 90% of primary tympanoplasties in different hands. However, in some situations such as advanced middle ear pathology, retraction pockets, and atelectatic ears, temporalis fascia tends to undergo atrophy in the subsequent postoperative period regardless of placement techniques . Our dissatisfaction with the temporalis fascia with a higher incidence of recurrent perforations compelled us to use a tougher material that would not only prevent reperforation but also prevent retractions. Cartilage has shown to be a promising graft material to close perforations in the tympanic membrane. Although it is similar to temporalis fascia, its more rigid quality tends to resist resorption, retraction, and reperforation, even in the milieu of continuous eustachian tube dysfunction .
Of the 23 well-defined cartilage tympanoplasty methods, Tos has classified them into 6 groups:
- 1.
Underlay palisade method of Heermann
- 2.
Onlay palisade method
- 3.
Method of broad palisades
- 4.
Method of underlay stripes
- 5.
Method of onlay stripes
- 6.
Dornhoffer mosaic cartilage tympanoplasty
The tragal cartilage is yellow fibroelastic cartilage. The cartilage is a relatively avascular tissue. The presence of cartilage canals through which blood vessels may enter cartilage is well documented. Each canal contains a small artery surrounded by numerous venules and capillaries. Cartilage cells receive their nutrition by diffusions from vessels. Cartilage cells–chondrocytes lie in spaces (lacunae) present in matrix. Ground substance is made of complex molecules containing proteins and carbohydrates (proteoglycans). These molecules form a meshwork that is filled by water and dissolved salts. The carbohydrates are chemically glycosaminoglycans including chondroitin sulfate, keratan sulfate, and hyaluronic acid. The core protein is aggrecan. The proteoglycan molecules are tightly bound. Along with the water content, these molecules form a firm gel that gives cartilage its firm consistency .
This rigidity of the cartilage that prevents reperforations is, however, considered to interfere with the sound conduction properties of the tympanic membrane. We describe our innovative method for harvesting tragal cartilage from the same endaural incision and also describe the preparation of the graft by slicing it so as to obtain acoustic benefits.
2
Materials and methods
A retrospective study of type 1 cartilage tympanoplasties operated by both the authors in MIMER Medical College and Sushrut ENT Hospital from May 2005 to January 2008 was carried out.
2.1
Study population
All cases of Safe Chronic Suppurative Otitis Media were included in the study. The patients in the study group ranged from 11 to 57 years. Only cases in which ossicular chain was intact and no mastoid surgery was performed were included in the study. The number of ears operated was 268. However, 15 patients failed to follow up after 3 months, 16 failed to follow up after 6 months, and 14 failed to follow up after 1 year and hence were excluded from the study. Hence, the number of ears included in the study was 223.
In all patients, a detailed history was taken. A thorough clinical examination of ear, nose, and throat was done with special reference to the ear. Otomicroscopic examination was done in all cases. Hearing was assessed with Tuning Fork. Preoperative and postoperative pure tone audiogram was done in all patients. Preoperative investigations included hemogram, bleeding and clotting time, urine for routine, and microscopy, HIV testing and hepatitis B surface antigen test. In patients older than 40 years, electrocardiogram and chest x-ray were done. All details of the patients including name, age, sex, address, mobile number, preoperative findings, and pure tone audiogram were entered in case sheets. In all patients, preoperative and postoperative video-otoendoscopic recording was done for documentation. All patients were assessed preoperatively by an anesthesiologist and were fit for surgery in American Society of Anesthesiologist (ASA) grade I or II. All patients were explained about the operative procedures failure rates along with the postoperative care to be taken. Written consent was taken in all patients.
2.2
Anaesthesia
All patients were operated under local anesthesia with adequate sedation except children who were operated under general anesthesia. Premedication included pentazocine lactate injection Indian Pharmacopoeia (IP) 30 mg/midazolam injection British Pharmacopoeia (BP) 1 mg/mL.
2.3
Infiltration
Two percent lidocaine with 1:200 000 adrenaline was used.
2.4
Procedure of sliced shield cartilage tympanoplasty
With proper aseptic precautions, Lempert’s endaural incision is taken. Tragal cartilage graft is harvested via the same incision, that is, by sharp dissection into vertical limb of Lempert’s incision ( Fig. 1 ). The cartilage with its attached perichondrium is dissected from overlying skin and soft tissue by a pair of sharp scissors in a plane that is easily developed superficial to the perichondrium on both sides ( Fig. 2 ). It is necessary to make an inferior cut as low as possible to maximize the length of the harvested cartilage graft ( Fig. 3 ). The superior cut is made leaving 5-mm strip of cartilage in the dome of the tragus for cosmesis ( Fig. 4 ). The cartilage is then grasped with plain forceps and retracted, and final cut is given on the fourth side (first side being the free edge along the incisura terminalis), which delivers a piece of cartilage measuring approximately 15 × 15 mm ( Fig. 5 ).
The thickness of the tragal cartilage is approximately 1 mm, and it has been suggested that thinning the cartilage to 0.5 mm could attain acoustic benefit. The thickness of the normal tympanic membrane is 0.1 mm. Hence, to achieve this acoustic benefit, we thin the cartilage with the help of a Cartilage Splitter (Kalelkar Surgical, Mumbai, India). The cartilage splitter is an assembly consisting of blade fixation instrument and other for cartilage stabilization ( Fig. 6 ). The peculiarity of the Cartilage Splitter is that it can produce cartilage slices of varied thickness ranging from 0.1 to 0.5 mm. Edges of the perforation in the pars tensa are freshened with the help of a sickle knife ( Fig. 7 ). Tympanomeatal flap is elevated after giving 6 o’clock and 12 o’clock incision. This can be extended up to 2 o’clock on anterior canal wall (considering right ear) leaving 6-mm canal skin from annulus tympanicus laterally. The whole elevated tympanomeatal flap is parked in attic area superiorly ( Fig. 8 ). Ossicular mobility and continuity are assessed. The handle of malleus is denuded. The tragal cartilage is firmly held with the help of cartilage splitter ( Fig. 9 ). The tragal cartilage is sliced with the help of cartilage splitter knife ( Fig. 10 ). The composite sliced cartilage-perichondrium shield graft of 0.5-mm thickness ( Fig. 11 ) is now placed by underlay technique in a meticulous manner after filling the middle ear with gel foam ( Fig. 12 ). Tympanomeatal flap is reposited back. Gel foam is placed over the graft. Meatal pack is placed. Endaural incision is sutured. Mastoid bandage is tied.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
