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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_4507_Библиотеки_им_академика_М_И_Перельмана.pdf
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Fig. 23.6 Anterior tympanomeatal ap elevation and cartilage graft placement
The technique commences with a meticulous inltration of anesthetic under
the periosteum of the external auditory canal and the perichondrium between the
tragus and the helix, both administered with a dental needle. This is followed by
the careful insertion of a curved nasal speculum for optimal visualization within
the canal. An initial oval-shaped incision then denes the base of the approach.
Beginning at the annulus between 6 o’clock and 12 o’clock, this incision is carefully extended to the bone–cartilage junction before returning to the annulus,
encompassing the periosteum along the way. A second incision completes the
exposure, extending from the 12 o’clock position on the tragus and continuing
upward from the end of the rst incision. The length of this second incision is
adapted to the intended procedure, extending 8–10mm for exploratory myringotomy and encompassing a larger subcutaneous area for mastoidectomy. Caution
is paramount while performing deeper incisions to avoid inadvertent injury to the
supercial temporal artery, vein, and fascia. Following meticulous ap elevation
through the external auditory canal incisions, automatic ear retractors are strategically utilized to optimize exposure. In particular, the Exploratris approach offers
the added benet of harvesting temporal fascia grafts through the same incision.
However, achieving successful outcomes with the Exploratris technique requires
careful consideration of the specic procedure being performed and the individual
patient’s anatomy [8, 16, 18, 30, 58].
23 Tympanoplasty
Table 23.3 The advantages and disadvantages of the postauricular incision
Advantages Disadvantages
Cosmetically acceptable Long recovery time
Broad surgical view Bleeding due to large
incision
If a temporalis muscle fascia graft is planned, a second incision is
not required.
Long surgery time
473
23.10.3 Postauricular Incision
The postauricular incision provides a versatile approach for various middle ear and
mastoid procedures. Traditionally, the incision begins 1.5–2 cm posterior to the
postauricular sulcus and extends in an oval shape from the superior auricular attachment to 1cm above the mastoid tip (3–4 cm in length). This approach provides
access to the periosteum for harvesting the temporalis fascia. A periosteal elevator
separates the soft tissue and periosteum from the bone anteriorly and posteriorly. An
automated retractor is then placed, and elevation continues anteriorly until the spine
of Henle and the external auditory canal are visualized. Depending on the specic
procedure, additional incisions and vascularization may be included in the external
auditory canal skin. Alternatively, in a modied approach, the incision begins within
the scalp, 1.5–2cm posterior to the sulcus, and remains oval, ending 1cm above the
mastoid tip. This incision traverses the skin and subcutaneous tissue and continues
the elevation to the external auditory canal opening. Two additional oval incisions,
0.5cm above and below the canal (extending 1–1.5cm posteriorly), may be used
depending on specic surgical requirements and patient anatomy. Regardless of the
variation, careful attention to the surgical procedure and patient anatomy guides the
precise location and extent of incision and elevation for optimal results.
It is important to note that neonates do not have a mastoid protrusion. In children
under 2years of age, the incision should be made horizontally above the auricle due
to the unique anatomy at this age. In this population, the antrum is located directly
above and behind the external auditory canal. Individualized surgical approaches
are crucial, especially in pediatric cases, to ensure optimal outcomes and minimize
potential impact on normal development [23, 25, 30, 39, 40, 58]. The advantages
and disadvantages of the postauricular incision are listed in Table23.3.
23.11 Pediatric Tympanoplasty
Although tympanoplasty remains a viable intervention for both pediatric and
adult patients, there is still debate regarding the optimal age for surgery. Some
authors advocate performing pediatric tympanoplasty primarily in patients
8years of age and older [60, 62], citing the potential for improved patient compliance and surgical precision. Conversely, others emphasize the potential benets of early intervention when appropriate conditions are identied [63, 64],
highlighting the concern that delayed surgery may increase the risk of inner ear
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I. Kaya et al.
complications. In the rst author’s clinic, the decision to proceed with tympanoplasty in pediatric patients is based primarily on factors other than age alone. In
children with minimal risk of cholesteatoma formation due to marginal perforation or epithelial ingrowth, we generally defer surgery until after 8years of age.
In addition to age, other factors that inuence the timing and potential outcome
of surgery in these patients include ET function, adenoid hypertrophy, and status
of the contralateral ear.
While successful TM closure in children offers a variety of potential benefits, ranging from improved hearing and speech development to the elimination
of chronic middle ear infections and the ability to safely participate in water
activities [64], the optimal timing of such interventions remains a subject of
debate, particularly with regard to the role of age as a prognostic factor. In
particular, there is conflicting evidence in the literature. Some studies have
observed a positive correlation between older age and better surgical outcomes
in pediatric tympanoplasty [60, 62], possibly due to improved patient cooperation and surgical precision. However, other studies have found no statistically
significant association between age and success rates [63, 64]. Interestingly,
there is encouraging evidence that certain techniques, such as cartilage type 1
tympanoplasty, may have positive long-term outcomes in the pediatric population [65]. Therefore, age alone may not be the most reliable predictor of success, requiring a nuanced approach that considers the interplay of multiple
factors in tailoring the timing and technique of tympanoplasty for each individual child.
23.12 Prognostic Factors
Despite the various studies conducted on the prognostic factors that play a role
in achieving successful outcomes or causing failure in COM surgery, there is no
globally accepted standard. In recent years, the Middle ear risk index (MERI)
system has become more widely used (Table23.4). ET insufciency is one of
the most important causes of surgical failure and in the etiopathogenesis of
COM.On the other hand, there is no denitive method to evaluate ET function
and middle ear-mastoid ventilation in the preoperative period and to guide early
and late prognosis in the postoperative period. The presence of ET dysfunction
can be assessed empirically if it is associated with mucosal disease during surgery. Findings such as blockage at the Eustachian orice, mucosal hypertrophy,
and mucoid secretion can be evaluated for ET dysfunction. The condition of the
middle ear and mastoid mucosa is also one of the most important prognostic
factors in chronic otitis surgery.
23 Tympanoplasty
475
Table 23.4 The Middle Ear
Risk Index
Risk Factor Risk Score
Otorrhea
Dry 0
Occasionally wet 1
Persistently wet 2
Wet, cleft palate 3
Perforation
Absent 0
Present 1
Cholesteatoma
Absent 0
Present 1
Ossicular status
Malleus+ incus+ stapes+ 0
Malleus+ stapes+ 1
Malleus+ stapes- 2
Malleus- stapes+ 3
Malleus- stapes- 4
Ossicle head xation 2
Stapes xation 3
Middle ear: Granulations or effusion
Absent 0
Present 1
Previous surgery
None 0
Staged 1
Revision 2
23.13 Contraindications forTympanoplasty
Candidacy for tympanoplasty depends on careful consideration of both absolute
and relative contraindications before proceeding with surgery. While absolute
contraindications unequivocally preclude the procedure, relative factors necessitate a nuanced approach and careful weighing of potential benets and risks.
Absolute contraindications to tympanoplasty include the presence of uncontrolled cholesteatoma; active intracranial complications of otitis media, such as
meningitis, abscess, or lateral sinus thrombosis; malignancy in the middle ear;
and specic patient-related contraindications to anesthesia. Relative contraindications include a broader range of factors that may inuence, but not necessarily
preclude, the decision to operate. These include patient age, especially in young
children or the elderly; a nonfunctioning ET; unilateral deafness where a tympanoplasty is being considered for the better ear; and uncontrolled otorrhea.
Preoperative assessment should meticulously evaluate both absolute and relative
contraindications to ensure patient safety and allow for appropriate surgical decision making [66].
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I. Kaya et al.
23.14 Conclusion
Tympanoplasty is a safe and effective surgical procedure that can improve hearing
and quality of life for people with conditions that damage the TM or middle ear
structures. The success of tympanoplasty depends on the severity of the underlying
condition and the skill of the surgeon. Over the past decade, the use of endoscopic
techniques and innovative graft materials in tympanoplasty has increased signicantly and revolutionized the practice of tympanoplasty. These advances have
resulted in improved surgical precision, reduced tissue trauma, and potentially
improved patient outcomes. Ongoing research continues to optimize these techniques and materials, further solidifying the future of minimally invasive and effective tympanoplasty procedures.
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I. Kaya et al.
Ossiculoplasty
24
GokceTanyeri Toker, OnurCelik,
andHermanArthurJenkins
24.1 Introduction
Ossiculoplasty is a reconstructive procedure designed to restore or repair the sound
conduction system between the tympanic membrane and vestibule by ensuring the
integrity and/or mobility of the ossicular chain. Terms such as ossicular reconstruction and ossicular chain reconstruction (OCR) have also been employed to describe
this procedure. Although ossiculoplasty is utilized for various indications (see indications), a signicant proportion of patients in routine daily practice develop defects
in the ossicular chain due to prolonged inammation in the middle ear air spaces.
The long crus of the incus, where the blood supply is the weakest, is the most susceptible to this slow erosion of the ossicles over time [1].
The primary objective of ossiculoplasty is to reconstruct hearing and achieve
functional improvement. To achieve this goal, surgeons must focus on the following
key aspects: (1) meticulously restore the anatomical structures, (2) establish a stable
and secure continuity between the tympanic membrane and the vestibule, (3) strive
to obtain the optimal and permanent hearing results, and (4) avoid complications.
This section provides concise information on the history, anatomy, and physiology
of ossiculoplasty. Subsequently, a detailed and up-to-date information is provided on
G. Tanyeri Toker (*)
Faculty of Medicine, Department of Otorhinolaryngology, Izmir Katip Çelebi University,
İzmir, Turkey
e-mail: gokce.tanyeri@gmail.com
O. Celik
Faculty of Medicine, Department of Otorhinolaryngology, Manisa Celal Bayar University,
Manisa, Turkey
e-mail: onurcelik@yahoo.com
H. A. Jenkins
University of Colorado, Bouldier, CO, USA
e-mail: herman.jenkins@cuanschutz.edu
© The Author(s), under exclusive license to Springer Nature
Switzerland AG 2024
M. T. Kalcioglu et al. (eds.), Otology Updates, Comprehensive ENT,
https://doi.org/10.1007/978-3-031-76173-7_24
479
480
the following aspects: indications and contraindications of ossiculoplasty, materials
used in reconstruction and their properties, patient evaluation before surgery, surgical
preparations, and surgical techniques, ossicular chain defects and reconstruction
options, postoperative outcomes, complications, and postoperative care.
G. Tanyeri Toker et al.
24.2 History ofOssiculoplasty
Ossiculoplasty was rst performed in the 1950s [2, 3]. Initially, reconstruction was
performed to ensure the integrity of the ossicular chain; this procedure was later applied
to eliminate movement limitations caused by tympanosclerosis. During the rst application, a polyethylene tube was used as the reconstruction material. Owing to the poor
results, biocompatible materials were preferred [4]. Autografts and allograft ossicles
have gained widespread use in this context. However, the utilization of allograft materials was limited due to the risk of transmitting diseases such as hepatitis, acquired
immunodeciency syndrome, and Jacob-Creutz-Feldt disease. Ossicular chain defects
were classied, and interposition techniques were described by Austin in 1971. As a
result, autografts have regained prominence. Nonetheless, a diverse array of materials
continues to emerge and are used [5]. The historical evolution and properties of the
materials used in ossiculoplasty are summarized in Fig.24.1 [2, 3, 6–29].
24.3 Anatomy andPhysiology
The ossicular chain is composed of three interconnected ossicles: the malleus,
incus, and stapes. The malleus, being the largest ossicle, has three parts (the caput
mallei, collum mallei, and manubrium mallei) and two protrusions (the processus
anterior and processus lateralis). The caput mallei articulates with the corpus incudis (incudomallear joints). The lateral process, manubrium, and umbo of the malleus are connected to the tympanic membrane. The incus has a body (the corpus
incudis) and two arms (the crus longum and crus breve). The free end of the crus
longum bent inward was identied as processus lenticularis. This protrusion is articulated with the head of the stapes (incudostapedial joint). The stapes have two parts,
the caput stapedis and basis stapedis, and two arms, the crus anterius and crus posterius, which connect these two parts. The basis stapedis covers the fenestra vestibuli (oval window) and is attached to the periphery of the window by the
ligamentum annulare. The ossicles are held in position and suspended within the
tympanic cavity by the ligaments, muscles, and folds. These muscles include the
musculus tensor tympani and the stapedius. In addition to maintaining the position
in the ossicular chain, the muscles protect the inner ear from potential damage
caused by high sound levels. The tensor tympani muscle, situated near the collum
mallei, can reduce vibration transmission by pulling the collum mallei medially to
stiffen its tympanic membrane. The stapedius muscle attaches to the head of the
stapes and reduces vibrations in the oval window during loud sounds [30].
Embryologically, the malleus and incus develop from the Meckel’s cartilage of
the rst pharyngeal arch, the stapes head and crura from the Reichert’s cartilage of
24 Ossiculoplasty
481
Fig. 24.1 History of the materials used in ossiculoplasty
the second pharyngeal arch, and the stapes base and annular ligament from the otic
capsule [31].
The ossicular chain assists in mechanically transmitting sound energy. Sound
energy is transmitted to the cochlea in two ways: through the tympanic membrane
and ossicles (tympano-ossicular transmission) and a direct transmission of sound
waves to the windows (acoustic transmission) [32]. If the sound energy directly
enters the base of the stapes, in the absence of the eardrum and ossicles, an impedance mismatch arises, resulting in 0.1% of the acoustic energy reaching the inner
ear [33]. To compensate for this mismatch, the ossicular chain functions serve as an
impedance-matching system that is responsible for transmitting more than 90% of
the acoustic energy to the inner ear. This gain granted by ossicular transmission is
provided by the area difference between the tympanic membrane and stapes (20/1)
and the leverage effect of the ossicular chain (malleus manubrium/incus short crus:
1.3/1). Considering both area differences and leverage effects, the accepted total