Report of 31 cases of auricular reconstruction due to congenital microtia by using autogenous costal cartilage

Auricular reconstruction represents a difficult reconstructive and aesthetic problem to the plastic surgeon. One of the greatest challenges in facial plastic surgery is total ear reconstruction. To date, no perfect material has been found to substitute for the elastic cartilage present in the normal ear. Total auricular reconstruction remains very complex.

REPORT OF 31 CASES OF AURICULAR RECONSTRUCTION

DUE TO CONGENITAL MICROTIA BY USING

AUTOGENOUS COSTAL CARTILAGE

Vu Duy Dung¹, Nguyen Roan Tuat¹, Le Gia Vinh²

¹Ha Noi Medical University

²Medical Military Academy Auricular reconstruction represents a difficult reconstructive and aesthetic problem to the plastic surgeon One of the greatest challenges in facial plastic surgery is total ear reconstruction To date, no perfect material has been found to substitute for the elastic cartilage present in the normal ear Total auricular reconstruction remains very complex Prosthetic restoration is not favored by most but does remain available option for many patients Tissue engineers have sought to create a precise three dimensional auricular neo-cartilage but autogenous cartilage remains the gold standard thus far This is a prospective study of thirty-one consecutive patients undergoing total auricular reconstruction for congenital microtia at the National Pediatric Hospital of Vietnam The operation had 3 stages: In the first stage, the 6th, 7th and 8th ribs are harvested for creation and implantation of a cartilaginous frameworks In the second stage, the lobule is transposed using a z-plasty of a narrow, inferiorly-based triangular flap In the third stage, the construct is elevated and the post-auricular sulcus

is covered with a split thickness skin graft in order to improve auricular projection The success rate was 78.8% with excellent, good or satisfactory results In 8 cases (21.2%), there was infection with loss of the cartilage Our study auricular reconstruction with autogenous costal cartilaginous has 78.8% success rate with satisfactory

to excellent, and cosmetic outcome and least complication results in our series support this conclusion.

I INTRODUCTION

Keywords: Microtia, congenital, auricular, reconstruction, costal cartilage.

Microtia is a rare condition, it affects only 1

in 7000 to 8000 births, though rates can vary

depending on ethnic background In 90% of

cases, it affects only one ear, usually the right

ear, and is more common in males Microtia

describes the outer ear, but is often associated

with absence of the ear canal (called ear canal

atresia) There are four grades of microtia:

Grade I: A less than complete development

of the external ear with identifiable structures and a small but present external ear canal Grade II: A partially developed ear (usually the top portion is underdeveloped) with a closed stenotic external ear canal producing a conductive hearing loss Grade III (is the most common form of microtia): Absence of the external ear with a small peanut like vestige structure and an absence of the external ear canal and ear drum (figure.1) Grade IV: Absence of the total ear or anotia

Reconstruction of the outer ear malformation cannot be done right after birth

Corresponding author: Vu Duy Dung,

Ha Noi Medical University

Email: dungent@gmail.com

Received: 27/11/2018

Accepted: 12/03/2019

Figure 1 Grade III microtia

Until the reconstruction can be done,

patients and families must cope with the

abnormality Total auricular reconstruction

using rib cartilage grafts have been shown to be

a reliable technique since the 1920’s It usually

involves two to four separate surgeries done

under anesthesia separated by several months

to allow for healing between each stage

There are several different rib cartilage graft

reconstruction techniques All involve taking rib

cartilage from the chest during the 1st stage

and carefully sculpting it into a framework that

is shaped like an ear This framework is then

implanted in a skin pocket underneath the

scalp on the skull where the new ear will be

located The newly created cartilage framework

becomes part of the patient’s live tissue, and is

incorporated after 3 to 4 months, at which point

the second stage of the surgery is performed

In the 2nd stage, incisions are made behind

the ear to release the ear from the scalp skin,

and the cartilage framework is lifted up to give

it adequate projection A skin graft is then used

to help cover the backside of the newly lifted

ear Sometimes, additional minor stages are

performed to improve the shape of the ear, the

appearance of scars, or project the ear even

further

Although some surgeons consider doing

rib cartilage graft reconstruction in patients as

young as 5 to 6 years of age, a much better and

more detailed 3-dimensional reconstruction

can be achieved at 8 to 10 years of age, when there is a thicker, more robust rib cartilage to use from the chest

At the National Pediatric Hospital of Viet Nam, we have begun performing microtia reconstructions using autologous costal cartilage in recent years, so that we do research with aim of study is to evaluate outcomes of these surgeries in our initial patient series

II METHODS

1 Study design

Prospective report thirty-one patients were operated for auricular reconstruction due to severe microtia at National Pediatric Hospital, from December 2015 to December 2017

2 Study process Patients selection:

Patients undergoing surgery were between ages of 6 and 18, with no prior surgery on the chest or affected temporal area, and had congenital microtia (grade III or IV)

Pre-operative preparation:

A thorough history and physical was performed on each patient, including attention to possible associated anomalies A psychological evaluation was also performed for each patient Preoperative design and planning of cartilage framework was performed The size, measurement and position of the ear were done by tracing an x-ray film pattern of the normal opposite ear This template pattern was later sterilized using cidex in the operating room, and positioned equidistant with the contralateral side as shown in figure.2

Figure 2 Preoperative planning

Operative details:

- First stage (creation and implantation of

cartilage graft framework): elevation of a thin

skin flap over the non-hair bearing auricular

area through an anterior limited incision Costal

cartilage is obtained through a transverse or

oblique incision over the 6th intercostal space,

using sub-perichondrial dissection The x-ray

pattern of the opposite ear is then placed

over the union between the 6th and 7th costal

cartilage to form the base block in which is

carved the scapha, antihelix, and triangular

fossa (figure.3)

Figure 3 Framework

The synchondrosis of this base is secured

using 4 - 0 Ethibond sutures The 8th cartilage is

harvested to form the helical rim and is sutured

to the base using 3.0 prolene A thin skin flap

is made at the affected temporal area, and

abnormal cartilage is removed The framework

is then implanted under this skin flap Low

negative suction is then applied to position

the skin flap, anchor the cartilage framework

and to reduce dead space and hematoma as

demonstrated in figure 4

Figure 4 Complete 1 st stage

- Second stage (Lobule transposition): To achieve maximal safety and reliability of the lobule, it is transposed during a second stage The rotation or reposition of this displaced structure is essentially done by z-plasty transposition of narrow, inferiorly based triangular flap

- Third stage (Auricular framework elevation): detachment of the constructed auricle and ear lobe positioning The post auricular sulcus is defined by elevating the constructed auricle from the scalp and by covering the undersurface with a thick split thickness skin graft Retro auricular skin is advanced into the newly created sulcus and a bolster dressing is placed to secure the graft

To augment the auricular elevation a sub facial mastoid pocket is created just behind the deepest point of the detached ear to harvest the cartilage wedge, graft bank in the post-auricular area as show in figure 5

Figure 5 Complete 2 nd stage

Time of follow up and assessment at least

3 months post-op, which were studied in the patients: age, sex involved, side involved, outcomes of procedures, and complications

Evaluation criteria:

For aesthetic outcomes (figure.6), observers evaluated frontal, lateral photographs of all patients and rated the reconstructed ear

on a scale of 3 with the following criteria [1]:

3 (excellent) all external ear anatomy well visualized, excellent projection, no revisions

necessary; 2 (moderate)—major external ear

anatomy visualized, reasonable projection,

minor revisions may improve outcome; 1

(unsatisfactory)—abnormalities in multiple

anatomical components of the ear, major

revisions necessary

Figure 6 Outcome of microtia

reconstructed

For analysis of landmark on pinna, based

upon Sharma et al grading system

Table 1 Mohit Sharma et al [2] grading

system for microtia

Anatomical attribute Score

Helix

Anti-helix

Superior and inferior

III RESULTS

In this study thirty-one patients were underwent ear reconstruction These patients ranged in age from 7 to 18 years old, with

a mean age of 11.7 The mean length of postoperative follow-up was 6 months, with a range of 3 to 14 months All patients exhibited grade III or IV microtia Demographic data are summarized in table 2

For the auricular reconstruction, cosmetic outcomes were satisfactory to excellent in 74.2% and 21.2% had unsatisfactory results All patients underwent microtia reconstruction

in 3 stages, with 13 cases (41.9%) needing further work (scar revision)

There were 6 cases of flap necrosis or skin graft compromise There were no cases

of framework exposure There were 11 minor complications, 2 of which resolved with conservative management For the most part, there were sub-centimeter wound dehiscence which resulted from trauma to the region in postoperative period

Table 2 Patient Demographics

There were 3 patients with postauricular hematoma, which were aspirated in the office Complication data are summarized in table 3 Representative preoperative and postoperative photographs are shown in figure 6

Table 3 Complications of Auricular

Recon-struction (33 Ears Available for Follow-up)

-Inspection of landmarks on reconstructed

Ear based upon Sharma et al…grading scale

(table 1) Each unit will be counted 1 point

so the between 0 to 13, and scale of 4 with

the following criteria On table 4 showing that

78.8% achieved satisfactory to excellent

outcomes, and 21.2% were unsatisfactory

Table 4 Grading scale for evaluating the results

78.8%

IV DISCUSSION

Tanzer [3] introduced total auricular

reconstruction using autologous costal cartilage

graft in 1959 with 6 stages and Brent [4] in

1974 modified this to 4 stages Their concept

of multistage treatment is now the state of art

solution for ear reconstruction Subsequently

Nagata [5] and Firmin [6] have further refined

this technique to a 2 stage reconstruction The

most important factor affecting the aesthetic outcome of the auricular reconstruction with rib costal cartilage graft is the fabricated cartilage framework

The autogenous cartilage graft is “gold standard” for the auricular reconstruction because of its availability, and durable results compared to other methods including synthetic materials and prostheses

In this study we compared our results in term of final aesthetic outcome and anatomical landmark on total 33 auricular reconstructed ears were done (in 31 patients) The operation was done under general anesthesia, spending 4-6 hrs with each case

The success rate was 78.8% with satisfactory to excellent but 21.2% of cases had an unsatisfactory result Meanwhile, Mohit Sharma [2] reported good or excellent results could be achieved in 70% but this difference with no significant

And the overall rate of complications was 33.3% (11/33 ears) was higher than Rachel et

al (18%)

Ear reconstruction in our group was performed as early as possible, after ages 7-10 years to allow the thoracic cage to be large enough to provide for an adequate size

of the framework In this series we started the ear reconstruction for 45.5% in those aged 7

- 11 years old (primary school-age), in 39.4%

for those 12 - 15 years old (secondary

school-age), and in 15.1% for those 16-18 years old

(high school-age)

V CONCLUSIONS

Reconstruction of the auricle is one of the

most challenging and rewarding aspects of

facial plastic surgery Each patient and each

ear deformity are unique, thus making the

management of these patients a humbling,

challenging, and perpetually stimulating

problem Autogenous costal cartilaginous graft

auricular reconstruction can be attempted with

good long term results In fact that a majority

had acceptable results however there is room

for improvement with further experience

REFERENCES

1 Rachel et al., (2017) Evaluation of 4

Outcomes Measures in Microtia Treatment:

Exposures, Infections, Aesthetics, and

Psychosocial Ramifications PRS Global Open, september, p 1-7.

2 Mohit Sharma et al., (2015) Objective

analysis of microtia reconstruction in Indian patients and modifications in management

protocol Indian J Plast Surg, May-Aug 48 (2):

p 144-152

3 Tanzer RC., (1959) Total reconstruction

of the external ear Plast Reconstr Surg Transplant Bull, 23: p 1-15.

4 Brent B., (1980) The correction of

microtia with autogenous cartilage grafts:

II Atypical and complex deformities Plast Reconstr Surg, 66: p 13-21.

5 Nagata S., (1993) A new method of total

reconstruction of the auricle for microtia Plast Reconstr Surg, 92: p 187-201.

6 Firmin F et al., (2011) A novel algorithm

for autologous ear reconstruction Semin Plast Surg, 25: p 257-64.