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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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Table 23.2 Graft materials
Temporal fascia
Tragal cartilage
Conchal cartilage
Tragal or Conchal perichondrium
Periosteum
Subcutaneous tissue
Fascia Lata
External ear canal
Fat tissue
23.8 Graft Techniques
23.8.1 The Perichondrium/Cartilage Island Graft
The perichondrium/cartilage island graft technique for tympanoplasty commences
with harvesting a graft from the tragus [47, 50]. This location is favored because of
the readily available at cartilage of sufcient size to reconstruct the entire TM.The
harvested cartilage can be used as a split-thickness or full-thickness graft, typically
exceeding 0.5 mm in most cases. While theoretical acoustic benets have been
attributed to thinning the cartilage to 0.5mm [51], this is often negated by the undesirable tendency of the graft to curl when excessively thinned against the attached
perichondrium. This curling phenomenon can compromise the stability and integration of the graft into the middle ear, leading surgeons to generally prefer slightly
thicker grafts for optimal surgical results.
The perichondrium/cartilage island graft, typically harvested from the tragus, is excellent for treating certain middle ear pathologies. Its inherent vascularity promotes graft survival and makes it ideal for managing atelectatic ears
where the middle ear cavity has collapsed. Furthermore, its robust structure is
well suited for high-risk perforations, providing superior stability and resistance
to retraction.
Perichondrium/cartilage island graft harvesting begins with an initial incision at
the medial tragus, sparing a 2-mm strip of cartilage in the dome for aesthetic considerations [50]. Sharp scissors meticulously dissect the cartilage from the overlying skin and soft tissue in a plane supercial to the perichondrium on both sides,
preserving the attached perichondrium. To maximize the length of the harvest, the
inferior cut should be made as low as possible.
Next, the superior portion near the incisura is released by grasping and retracting
the cartilage inferiorly. Further careful dissection during retraction typically yields
a piece of cartilage measuring 15mm×10mm in children and slightly larger in
adults. The perichondrium on the side furthest from the ear canal is then removed,
leaving the thinner perichondrium on the other side. This prepares the foundation
for the actual perichondrium/cartilage island graft construction.
As previously described [50], a round knife meticulously removes cartilage to
create an eccentrically located disc of approximately 7–9mm in diameter for complete TM reconstruction. A posterior perichondrial ap is fashioned for eventual
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463
draping over the posterior canal wall. A central vertical strip of cartilage measuring
2mm in width is then carefully removed to accommodate the entire malleus handle.
In situations with inadequate graft-TM remnant contact in the anterior TM
region, a modied composite cartilage/perichondrium island graft model provides a
promising solution. This model features a cartilage component that is truncated in
the posterior half compared to the anterior half (Fig.23.1). The rationale behind this
design is to optimize graft-TM contact in the critical anterior region by ensuring that
the cartilage completely covers the space anterior to the malleus handle. This modied island graft has two major advantages over the conventional model. First is its
reduced posterior stiffness. The shorter posterior cartilage minimizes potential
interference with ossicular motion and contact with the bony annulus, thereby
reducing graft-related stiffness. The second advantage is the enhanced anterior contact. The extended anterior cartilage portion effectively bridges the gap anterior to
the malleus handle, creating optimal contact with the remaining TM.
This novel approach addresses a critical challenge in tympanoplasty and may
result in improved graft integration and functional outcomes. By removing a strip of
cartilage and creating two distinct islands of cartilage, the graft can stretch and
adapt to the conical shape of the natural eardrum. If the ossicular chain is intact, an
additional triangle is removed from the back to accommodate the incus. This prevents the posterior part of the graft from shifting laterally, which can occur when the
malleus and incus are close together and there is not enough space.
Inadequate removal of cartilage from the central strip has two potential complications. First, insufcient cartilage excision can lead to the graft to fold medially
instead of assuming the desired at conguration. Second, a narrow strip risks
medial displacement of the entire graft relative to the malleus, altering its optimal
position. To prevent these complications and ensure proper support, materials such
as foam or platelet-rich brin (PRF) packing are carefully placed in the middle ear
space beneath the anterior annulus. In addition, the posterior perichondrium ap is
Fig. 23.1 Modied
asymmetrical composite
cartilage/perichondrium
island graft
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carefully draped over the posterior canal wall for further stabilization. Special care
is taken to avoid packing the promontory or the vicinity of the ossicular chain,
which may compromise its function.
23.8.2 The Palisade Graft
The palisade technique for tympanoplasty utilizes cartilage harvested from either
the tragus or the cymba, depending on the surgical approach chosen. When a postauricular incision is utilized, the cymba, located within the conchal bowl, is an easily accessible source of suitable cartilage. Its thickness of approximately 1mm is
similar to that of the tragus, which is an advantage over the thicker and more irregular cartilage found in other concha regions. However, the inherent curvature of the
cymba presents a challenge in constructing a perichondrium/cartilage island ap
large enough for complete TM reconstruction. Therefore, in transcanal or endaural
approaches where cartilage harvesting prioritizes minimal donor site morbidity, the
tragus becomes the preferred option due to its readily accessible at cartilage suitable for ap creation.
The palisade technique takes a unique approach to TM reconstruction. Instead of
using a single large graft, it meticulously assembles the membrane from multiple
thin cartilage slices. This modular approach accommodates the inherent curvature
of the cymba cartilage, making it a viable alternative to the tragus when a postauricular incision provides optimal surgical access.
The palisade technique, utilizing either tragus or cymba cartilage, excels in scenarios involving cholesteatoma and specic ossicular chain considerations. Its layered, overlapping placement provides excellent coverage and promotes tissue
integration, making it a preferred choice for cholesteatoma removal. In addition,
this technique allows for simultaneous ossicular reconstruction if the malleus
remains functional, further enhancing the potential for auditory rehabilitation.
Generous exposure is achieved by elevating the subcutaneous tissue and postauricular muscle from the conchal perichondrium to harvest cymba cartilage. The
cymba itself is readily identied as the prominent bulge on the superior aspect of the
concha. A circumferential incision meticulously sized to the anticipated graft
dimensions is then made through both the perichondrium and cartilage, carefully
preserving the anterior skin layer. The perichondrium is then carefully dissected
from the postauricular side, leaving the harvested cartilage with its remaining anterior perichondrium intact. This harvesting technique offers a versatile source of cartilage, not only for TM reconstruction but also for canal wall reconstruction in
retrograde mastoidectomy for cholesteatoma surgery.
A modication of the palisade tympanoplasty technique was originally described
by Heermann et al. [52]. Rather than juxtaposing rectangular strips of cartilage,
their approach emphasizes the meticulous crafting of a single, large, semilunar
piece of cartilage. This key element is strategically positioned directly against the
malleus and atop the ossicular prosthesis, effectively reconstructing a signicant
portion of the posterior TM and providing a stable foundation for subsequent
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cartilage placement. A second semilunar piece is then meticulously positioned
between the initial graft and the canal wall to precisely reconstruct the scutum. Any
remaining gaps between the reconstructed scutum and the canal wall or initial cartilage piece are meticulously lled with slivers of cartilage to effectively prevent
prosthesis extrusion and recurrent retraction. Finally, the meticulously harvested
perichondrium is carefully draped over the posterior canal wall to complete the
reconstruction.
This modied palisade approach offers versatility that extends its utility
beyond stand-alone TM reconstruction. It has been shown to excel in scenarios
requiring simultaneous ossiculoplasty with an intact malleus, particularly in the
context of cholesteatoma surgery. Notably, this technique prioritizes placement
of the ossicular prosthesis prior to cartilage reconstruction. This facilitates
direct visualization and contact between the notched prosthesis and the malleus
handle, a factor that has been shown to be associated with superior hearing outcomes [53].
The ossicular prosthesis serves a dual purpose in this modied palisade technique. First, it acts as a stable scaffold upon which the meticulously crafted cartilage
pieces are carefully positioned, facilitating precise reconstruction of the TM.This
scaffold effectively reduces the risk of prosthesis extrusion, a potential complication
in middle ear surgery. Second, the prosthesis allows for the meticulous creation of a
watertight seal between the reconstructed TM and the canal wall, particularly in the
crucial posterior area. This improved seal is particularly benecial in cholesteatoma
surgery where recurrent disease is common. While this technique prioritizes reconstruction of the posterior TM with the prosthesis-cartilage composite, the anterior
half is typically left intact or grafted with conventional materials. This preserves
crucial access for cholesteatoma surveillance and allows for potential postoperative
intubation if necessary.
23.8.3 The Temporalis Fascia Graft
The most commonly used graft material in tympanoplasty is the temporalis fascia.
It is a thin, pliable sheet of tissue that is easily harvested from the temporalis muscle
behind the ear. Temporalis fascia has several advantages over other graft materials,
including ease of harvest, adequate thickness, and good malleability. Temporalis
fascia can be harvested under local anesthesia in an outpatient setting. This eliminates the need for general anesthesia, which can be associated with risks and complications. The temporalis fascia is typically 0.2–0.3 millimeters thick, which is
sufcient to provide adequate support for the TM.Finally, the temporalis fascia
molds easily to the defect in the TM.This helps ensure a good seal and prevents
recurrent perforation.
There are some disadvantages of temporalis fascia as a graft material in tympanoplasty. In some cases, harvesting temporalis fascia can cause pain, swelling, and
bruising at the donor site. In addition, temporalis fascia can shrink over time, which
can lead to recurrent perforation.
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I. Kaya et al.
23.8.4 Cubism Graft asaNovel Graft Technique
The growing popularity of endoscopic tympanoplasty has spurred the development
of novel grafting techniques to overcome anatomic challenges and improve surgical
outcomes. In the rst author’s clinic, we have implemented a unique approach to
TM reconstruction that builds upon the established chondro-perichondrial island
graft. This innovative technique, aptly named the “cubism graft,” incorporates cartilage powder–enriched PRF onto the pre-harvested island graft [54]. This modication offers several potential advantages: enhanced graft stability, improved healing
potential, and tailored graft thickness, as discussed below.
The PRF, rich in growth factors and brin mesh, facilitates tissue adhesion and
vascularization, potentially promoting faster graft integration and reducing graft displacement. The cartilage powder within the PRF matrix acts as a scaffold, providing
additional structural support and potentially stimulating chondrogenic differentiation
for enhanced TM regeneration. Finally, the malleable PRF–cartilage mixture allows
the graft to be shaped to precisely match the desired thickness and contour of the TM,
potentially improving sound transmission and functional outcomes.
The rst step in this technique is obtaining cartilage dust and forming the island
graft: Using the ipsilateral tragal cartilage as the donor site, the perichondrium is
meticulously dissected from the convex surface of the cartilage, preserving the perichondrium on the concave surface. With a size 11 scalpel blade held perpendicular
to the cartilage, the perichondrium-free side is thinned using a controlled “brushing” technique. Gentle, rapid strokes are made without angular deviation, accumulating dough-like cartilage dust on the scalpel. This achieves the desired cartilage
thickness while avoiding excessive bending and maintaining a at island graft morphology. The cartilage island is meticulously shaped using a piecemeal peripheral
removal approach, incorporating a notch for the malleus handle. This part of the
procedure is shown in Fig.23.2.
a
def
Fig. 23.2 Surgical technique of the cubism graft: (a) Holding the no. 11 surgical blade perpen-
dicular to the cartilage. (b) Cumulation of cartilaginous dust while brushing the cartilage. (c)
Accumulated dough-like cartilaginous dust. (d) Spreading the cartilaginous dust. (e) From left to
right; a curled partial-thickness cartilage graft after slicing, a at partial-thickness cartilage island
graft after dust harvesting, a thinner cartilage graft after dust harvesting, the cartilaginous dust. (f)
Flat partial-thickness cartilage island graft
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a
c
Fig. 23.3 Surgical technique of the cubism graft: (a) Cutting the platelet-rich brin (PRF) into
pieces. (b) Mixing the cartilaginous dust and PRF. (c) Crushing the cartilage dust-PRF mixture
between two thick glass slides. (d) The thin, sticky cubism graft
b
d
Fig. 23.4 The cubism graft
The PRF is then prepared. Approximately 10mL of venous blood is collected in
sterile, anticoagulant-free tubes and centrifuged at 3000rpm for 10min. The resulting PRF, which forms a brin clot in the upper layer, is carefully extracted and
mixed with the harvested cartilage dust. This mixture is thoroughly crushed between
two thick glass slides, incorporating additional dust and PRF if necessary, to obtain
a thin, cohesive “cubism graft” This part of the procedure is shown in Fig.23.3. The
cubism graft is shown in Fig.23.4.
For graft placement and closure, the pre-shaped cartilage island graft is positioned in an “over-underlay” fashion, lateral to the malleus handle and medial to the
TM and annulus. The “cubism graft” is then meticulously placed over the island
graft as a second layer (Fig.23.5).
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Fig. 23.5 Placement of
the cubism graft over the
cartilage island graft
I. Kaya et al.
This innovative approach exemplies the ongoing advances in otologic surgery
to optimize TM reconstruction and improve patient hearing.
23.9 Surgical Approaches
23.9.1 Microscopic Approach
In modern tympanoplasty, the postauricular and transcanal approaches are often
used because of their excellent access and minimal external scarring. Although
less commonly used, the Lempert endaural approach remains a viable option in
certain cases. This technique involves a semicircular incision approximately
1cm posterior to the auricle fold, followed by mobilization of the anterior ear
to expose the musculoperiosteum. A musculoperiosteal ap is created and elevated toward the membranous ear canal, providing access to the bony canal. The
posterior skin of the bony canal is then elevated until reaching the tympanomeatal ap incisions. The ap is then elevated, allowing direct visualization of the
middle ear cavity.
If necessary, an ossiculoplasty can be performed at this stage to address the
ossicular chain disruption. The TM perforation is then meticulously repaired
with scissors or cup forceps. Reconstruction is achieved using an underlay
technique in which the TM limbus is undermined, the native membrane is elevated, and the perforation is covered medially with a carefully placed graft. For
optimal graft success, the autologous tissue should completely encompass the
TM defect while being securely anchored to the surrounding canal for longterm stability. When elevating the limbus from its bony sulcus in the posterior
region, care must be taken to avoid inadvertent injury to the chorda tympani
nerve [2].
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23.9.2 Endoscopic Approach
Endoscopic tympanoplasty offers a minimally invasive alternative to the traditional postauricular and endaural approaches to TMP repair. With a transcanal
approach and no external incisions, it allows for extensive visualization of the
middle ear anatomy, potentially resulting in shorter operative and recovery
times compared to microscopic techniques [55, 56]. Similar rates of perforation
closure and audiologic improvement have been reported [56]. However, limitations include one-handed manipulation and potential thermal damage to surrounding structures from the light source of the endoscope. The procedure
begins with edge de-epithelization of the perforation, similar to microscopic
tympanoplasty. An incision is made in the ear canal (swing door, endaural, or
lateral circumferential) to elevate the tympanomeatal ap and annulus to allow
access to the middle ear. The malleus is then separated from the TM and ossiculoplasty is performed if necessary. The prepared graft is positioned medial to the
TM remnant and lateral to the malleus, followed by the placement of Gelfoam
sponges in the middle and outer ear canals.
As an inlay graft technique, the “buttery cartilage tympanoplasty technique”
eliminates the need for tympanomeatal ap elevation [57]. In this technique, cartilaginous pseudo-anges are created to hold the graft in place. The graft is positioned
with one ange medial to the TM and the other lateral. Once secured, Gelfoam
sponges are arranged around the graft’s border.
23.10 Incisions inTympanoplasty
Tympanoplasty is based on three primary surgical approaches: transmeatal, endaural, and postauricular. Each technique offers distinct advantages and limitations,
highlighting the lack of a universally superior approach suitable for all TM perforations. Therefore, the optimal choice of incision for tympanoplasty requires careful
consideration of the specic characteristics of the disease, particularly its location
and extent.
Understanding the unique features of each incision allows surgeons to tailor
their approach to the individual needs of the patient. The endaural, postauricular, and transmeatal options provide flexibility to address different cases of
TMP and offer optimal outcomes based on the location and severity of the
pathology. In conclusion, the selection of the appropriate incision for tympanoplasty is a crucial decision that should be guided by a thorough assessment of
the patient’s condition to ensure an effective and personalized surgical intervention [58].
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23.10.1 Transmeatal Incisions
The transmeatal approach stands out as the sole method that eliminates the need for
an external incision. However, its application becomes challenging in cases where
the external ear canal is narrow. The use of a large, nonreecting ear speculum is
essential for transmeatal procedures [59]. To facilitate a two-handed approach, automatic ear speculums or speculum holders xed to the table are often used. A substantial ear speculum is inserted into the external ear canal and serves as the entry
point for surgical procedures performed through the ear speculum. Two distinct
incisions are utilized in transmeatal interventions: the Rosen incision, which is used
for exploratory myringotomy and the underlay technique, and the incisions used for
the Onlay technique [59].
23.10.1.1 The Rosen Incision
The endaural approach developed by Rosen is particularly useful for treating posteriorly located TM perforations using the underlay technique. It also facilitates ossiculoplasty and exploratory myringotomy procedures. Following meticulous
periosteal inltration with an anesthetic agent via dental needle, particularly in the
suture regions, a wide ear speculum is positioned to minimize bleeding and allow
for gentle periosteal scraping. Vertical incisions, typically 8–10mm in length, are
then meticulously placed between the 6–11 o’clock and the 7–12 o’clock positions,
commencing just superior to the annulus and extending down to the bone, encompassing the periosteum. Using a sickle or axe scalpel, these incisions are meticulously connected at the superior aspect, either in an oval conguration or parallel to
the annulus. The external ear canal skin is then carefully elevated from superior to
inferior using medium-sized mirror elevators, taking care to preserve skin integrity.
Any remaining incompletely dissected areas are cautiously opened with microscissors, avoiding excessive force. As the skin peels down towards the annulus, a thin
aspirator tip or cotton-covered tip is utilized to avoid skin injury. Once the annulus
is reached, the middle ear is accessed with increased caution, entering below the
annulus where the skin is thinner.
Throughout the incision process, the skin of the external auditory canal, TM, and
annulus can be tilted forward to optimize the visual eld. This approach allows for
either stapedectomy or ossiculoplasty, or the placement of a graft as an underlay,
depending on the specic surgical objectives. This incision technique plays a key
role in enabling effective and minimally invasive interventions within the middle
ear through the transmeatal approach [60].
23.10.1.2 Incisions Used forOnlay Technique
With this incision, the transmeatal approach initiates with meticulous inltration of
the entire periosteum of the external auditory canal using an anesthetic administered
through a dental needle. This is followed by secure placement of a large ear speculum for optimal visualization. Two parallel incisions, 8–10mm apart and 6–8mm
long, are carefully placed on the posterior wall skin between the 6–11 o’clock and
the 7–12 o’clock positions, perpendicular to the TM. These incisions create a
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vascular stripe and extend inferiorly to the bone. They are connected by a horizontal
incision along the posterior wall 1–2 mm above the annulus and parallel to the
TM.This meticulous dissection is continued superiorly using a small mirror carefully maneuvered along the incision with an elevator. Simultaneously, a second incision is meticulously created 8–10 mm above the TM, connecting the existing
superior vertical incisions on the anterior wall. Utilizing small mirror elevators, the
external auditory canal skin is meticulously elevated toward the TM, carefully preserving the epithelial layer on the TM for subsequent grafting. This epithelial layer
is then meticulously dissected from the underlying periosteum and preserved in
serum along with the canal skin for later use in the graft. In particular, the bony
annulus requires dissection with a cutting tool due to the fusion of the canal skin
periosteum with the underlying osseous structure. Throughout the procedure, thorough removal of all overlying epithelium from the TM is crucial for successful
grafting [5, 7, 58].
23.10.1.3 Anterior Tympanomeatal Flap
Limited visualization and an insufcient anterior TM remnant pose signicant challenges for both inlay and underlay tympanoplasty techniques in anterior perforations. Improper graft placement, particularly inadequate coverage or damaging
annulus elevation, can lead to complications such as blunting and inferior hearing
outcomes.
Transcanal cartilage endoscopic tympanoplasty with anterior tympanomeatal
ap elevation is a minimally invasive and feasible solution for anterior perforations
comprising less than 50% of the TM [61]. This approach offers several advantages
over conventional techniques.
Reduced invasiveness: The anterior tympanomeatal ap incision is intentionally
designed to be less than half the size of the annulus and remains medial to the malleus handle, effectively protecting the malleus region of the TM.
Improved visualization: Flap elevation signicantly improves access to the anterior TM defect, facilitating precise graft placement.
Simplied dissection: Minimal tissue dissection is required, eliminating potentially risky maneuvers such as malleus handle or chorda tympani dissection.
Preserved anatomy: The technique avoids unnecessary disruption of crucial
structures, potentially promoting faster healing and better functional outcomes.
The detailed steps of the anterior tympanomeatal ap elevation are shown in
Fig.23.6.
23.10.2 Endaural Incision
The exploratris approach demonstrates remarkable versatility and serves as a valuable technique for various otologic procedures, including myringotomy, tympanoplasty, and even mastoidectomy. While its broad applicability is evident in these
procedures, it’s important to recognize its potential limitations in scenarios involving extensive mastoid cavities or procedures requiring frontal access.