What are the different types of tympanoplasty?

Types of Tympanoplasty

Tympanoplasty procedures are classified into five main types based on the extent of middle ear reconstruction required, with each type addressing progressively more complex middle ear pathology.

Classification of Tympanoplasty Types

• Type I (Myringoplasty): Repair of the tympanic membrane perforation only, with an intact and normal functioning ossicular chain 1

  • Most commonly performed using temporalis fascia graft in either underlay or overlay technique 2
  • Button hole technique can be used, which involves anchoring the temporalis fascia to the handle of malleus through a buttonhole, showing slightly better graft uptake rates (96.7%) compared to standard underlay technique (93.3%) 2

• Type II: Repair of tympanic membrane perforation with erosion of the malleus, involving grafting to the incus or remnant of the malleus 3

• Type III (Myringostapediopexy): Repair of tympanic membrane with erosion of malleus and incus, placing the graft directly onto the stapes head 1, 3

• Type IV: Repair when the stapes superstructure is also eroded, with the graft placed directly on the mobile stapes footplate 3

  • Indicated in cases of severe atelectasis, patients with cleft palate, erosion of the footplate, and surgery on the better-only hearing ear 3
  • Despite advances in ossicular prostheses, still has a place in modern otology with 26% of patients achieving postoperative hearing levels <40 dB 3

• Type V: Repair when the stapes footplate is fixed, requiring fenestration of the lateral semicircular canal 1

Surgical Approaches for Tympanoplasty

• Incision approaches should be selected based on the location and extent of disease 4:
  • Endaural approach: Best for posterior tympanic membrane perforations and ossicular chain visualization 4
  • Postauricular approach: Provides better exposure of the anterior tympanic membrane while preserving the anterior canal wall skin 4
  • Transmeatal approach: Reserved for smaller central perforations with limited risk of epithelial ingrowth into the middle ear 4

Graft Materials and Techniques

• Cartilage tympanoplasty methods can be classified into six main groups 5:

  • Group A: Palisades, stripes, and slices of full-thickness cartilage with attached perichondrium 5
  • Group B: Foils, thin plates, and thick plates without perichondrium 5
  • Group C: Cartilage-perichondrium composite island grafts with perichondrium flap for suspension 5
  • Group D: Special total pars tensa cartilage-perichondrium composite grafts 5
  • Group E: Composite island grafts for anterior, inferior, and subtotal perforations 5
  • Group F: Special methods with cartilage disc under the perforation and perichondrium on the denuded eardrum remnant 5

• Perichondrium-cartilage grafts show high success rates in both children and adults:

  • 93.2% tympanic membrane closure rate 6
  • 93.1% achievement of air-bone gap <20 dBHL 6
  • Combined success rate of 86.3% 6
  • Larger perforations (>50%) have significantly lower closure rates (55.6% vs. >97%) 6

Clinical Considerations

• Adenoidectomy should be considered as an adjunct to tympanoplasty in children:

  • Children who underwent prior adenoidectomy had significantly higher tympanoplasty success rates 6
  • Recommended for children aged 4 years or older with symptoms related to adenoids or to reduce future recurrence of otitis media 1, 7

• Tympanostomy tubes are recommended as the initial surgical procedure for otitis media with effusion before considering more extensive tympanoplasty 1, 7:

  • Short-term tubes are preferred for initial surgery unless there is a specific need for prolonged ventilation 7
  • Long-term tubes should not be placed as initial surgery unless there is an anticipated need for extended middle ear ventilation 1

Potential Complications

• Tympanic membrane perforation occurs in approximately 2% of children after placement of short-term tubes and 17% after long-term tubes 1

• Other sequelae include otorrhea (discharge), tympanosclerosis, focal atrophy, or shallow retraction pockets, which are generally transient or do not affect function 1, 7

• Anesthesia risks must be considered, with reported mortality rates of approximately 1:50,000 for ambulatory surgery 1

• Adenoidectomy complications include a 0.2% to 0.5% incidence of hemorrhage and 2% incidence of transient velopharyngeal insufficiency 1

By understanding the different types of tympanoplasty and their indications, clinicians can select the most appropriate surgical approach based on the extent of middle ear pathology, optimizing outcomes for hearing restoration and quality of life.