International Journal of Pediatric Otorhinolaryngology (2005) 69, 335—344
www.elsevier.com/locate/ijporl
Circumferential trachea reconstruction with a prefabricated axial bio-synthetic flap: experimental study Ayhan Okumus¸a,*, Orhan C ¸izmecia, Fatih Kabakasa, Samet V. Kuvata, Ayhan Bilirb,1, Atakan Aydina a
Istanbul Medical Faculty, Department of Plastic and Reconstructive Surgery, Istanbul University, Istanbul, Turkey b Istanbul Medical Faculty, Department of Histology, Istanbul University, Istanbul, Turkey Received 28 March 2004; received in revised form 11 October 2004; accepted 13 October 2004
KEYWORDS Trachea reconstruction; Prefabrication; Polypropylene mesh
Summary Objective: The ideal method, in reconstruction of circumferential tracheal defects more than 50% of the total tracheal length, is still a question. Current methods lack either in epithelial lining or in skeletal framework. In this study, we designed an axial biosynthetic prefabricated flap to reconstruct the circumferential tracheal defects in rabbits. Methods: Ten rabbits are used. The inner mucosal lining is substituted by hairless epithelium obtained from proximal ear. The tracheal cartilage is substituted by polypropylene mesh and the tracheal adventitia is substituted by lateral thoracic fascia as a vascular supply. The study is designed in three stages. Stage 1: Hairless epithelial graft is obtained by secondary healing of a full thickness skin defect in ear. Stage 2: Epithelial graft, polypropylene mesh and lateral thoracic fascia are tubed around a silicone catheter. This structure is dissected through its pedicle (lateral thoracic vessels and fascia) to the axilla and mobilized. The prefabricated neotrachea is carried on its pedicle to the cervical area through a subcutaneous tunnel formed superficial to the sternum and left there for 2 weeks. Stage 3: The silicone catheter is taken out and prefabricated neotrachea is adapted to the defect formed in native trachea and anastomized. Later the animals are evaluated for 4 weeks. The patency of the lumen, the viability of the epithelial graft and fascia, airtightness of the anastomoses and other features of the reconstruction are evaluated by radiological, macroscopical and histological examinations.
* Corresponding author. Present address: Nevbahar Mah. Cevdetpas¸a Cad. Nilay Apt. 95/4 Fatih, ˙Istanbul, Turkey. Tel.: +90 532 671 39 93/212 5868057/212 4142000x32492; fax: +90 212 534 68 71. E-mail address:
[email protected] (A. Okumus¸). 1 Tel.: +90 212 4142000x32362. 0165-5876/$ — see front matter # 2004 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ijporl.2004.10.005
336
A. Okumus¸ et al.
Results: Survival at 4 weeks was 70%. All of the prefabricated neotracheas and epithelial grafts were viable. The rigidities, longitudinal elasticities, diameters and wall thickness were similar to native tracheas. Occlusion of lumen is encountered only in one animal. There was no hair growth from the epithelial lining. Conclusion: The study defines a new method of circular tracheal reconstruction with successful substitution of inner lining, skeletal framework and vascular supply. # 2004 Elsevier Ireland Ltd. All rights reserved.
1. Introduction The choice of alternative methods in reconstruction of circumferential tracheal defects basically depends on the length of the defect. Primary endto-end anastomosis without excessive tension is the desired procedure [1]. However, it can only work on defects no longer than 5—6 cm [2]. Circumferential defects longer than 5—6 cm or more than half of the total tracheal length can only be reconstructed by using local or distant tissues [3,4] or by synthetic grafts. Appropriate tissue combination and a widely accepted method have not been established in reconstruction of circumferential defects longer than the half of the total length of trachea. Synthetic materials are far from being optimal and no autologous reconstruction technique has been proven to be effective [3]. Non-circumferential tracheal wall defects can be handled by using autologous tissue but circumferential defects will need more. In optimal tracheal reconstruction, the substitute bridging the defect must be airtight, rigid enough to avoid collapse, longitudinally flexible, lined by an epithelial layer, and finally well vascularised to avoid infections and to provide acceptable wound healing. Therefore, the substitute should have three basic components; an inner epithelial lining, a skeletal framework and a rich blood supply. In this study, we designed an axial biosynthetic prefabricated flap [5] to reconstruct the circumferential tracheal defects in rabbits. The inner mucosal lining is substituted by hairless epithelial graft obtained from proximal ear (the method will be explained). The tracheal cartilage is substituted by polypropylene mesh and the tracheal adventitia is substituted by lateral thoracic fascia as a vascular supply.
2. Materials and methods Ten adult female New Zealand rabbit weighting 3— 3.5 kg have been used. All the operations have been performed under IM ketamin hydrochloride (50 mg/ kg), xylazin hydrochloride (5 mg/kg) anesthesia. All
procedures have been performed under sterile conditions, all animals received humane care in compliance with the European Convention on Animal Care and our institutional ethics committee approved the study. The study is designed in three stages.
2.1. Stage 1: obtaining hairless epithelial graft To obtain a hairless epithelial lining, 3 cm 3 cm full thickness skin graft is harvested from most proximal inner ear. The defect is left to heal secondarily. After 3 weeks, the defect is re-epithelised by secondary healing and contraction. Epithelium covering the defect was hairless. By this way, a hairless 2 cm 2 cm hairless epithelial graft donor site has been prepared (Fig. 1a).
2.2. Stage 2: prefabrication Hairless epithelial graft of 2 cm 2 cm is harvested from previously prepared site in proximal inner ear. Polypropylene mesh of 1.6 cm 1.6 cm prepared and sutured on the dermal side of the graft, leaving 2 mm bare graft at the periphery. Plane catgut is used as the suture material and the knots are kept on polypropylene mesh side (Fig. 1b). Then the lateral thoracic fascia is prepared. Skin incision is done starting from xiphoid going to the lateral at the distal abdominal portion. The reflection of lateral thoracic artery can be inspected externally in the lateral thorax. The incision is planned medial to the pedicle. Dissection is performed under lateral thoracic fascia to release skin and fascia flap from thorax and abdominal wall. Later previously sutured and prepared polypropylene mesh and hairless epithelial graft is adapted to the lateral thoracic fascia on the most distal bifurcation of the lateral thoracic artery (Fig. 2a). The epithelial graft is sutured to the fascia at its 2 mm periphery where there is no polypropylene mesh. So that the polypropylene mesh is embedded and hidden between epithelial graft and fascia to be away from the later anastomosis sites. The fascia under the epithelial graft and polypropylene mesh is
Reconstruction of circumferential trachea
337
Fig. 1 (a) The defect is left to heal secondarily and re-epithelised by a hairless skin. (b) Polypropylene mesh of 1.6 cm 1.6 cm is sutured at dermal side of 2 cm 2 cm hairless skin graft leaving 2 mm bare skin graft at the periphery.
Fig. 2 (a) The skin graft and polypropylene mesh is sutured to the lateral thoracic fascia at 2 mm periphery of skin graft. The polypropylene mesh is hidden between fascia and skin graft. (b) Illustration showing the relations of fascia, skin graft and polypropylene mesh around the catheter.
338
A. Okumus¸ et al.
Fig. 3 (a) Illustration of the transport of prefabricated neotrachea to the cervical area based on its pedicle. (b) The view of the lumen after taking the silicon catheter out.
incised and released from the skin and later it is tubed around a silicone 16-F urinary catheter (Fig. 2b). The pedicle is kept in the lateral side of the tube not to be involved in the anastomosis sites. The pedicle is dissected through the axilla and mobilized. It is carried to the cervical area through a subcutaneous tunnel formed over the sternum (Fig. 3a). In the cervical area, the prefabricated flap is fixed near the native trachea to wait for 2 weeks.
2.3. Stage 3: anastomosis Two weeks after the Stage 2 (prefabrication), a longitudinal incision is performed in anterior neck and cervical native trachea and prefabricated trachea is dissected. The prefabricated trachea is evaluated before the anastomosis. There was no problem with circulation of the flap. After taking out the silicone tube from the lumen, there has not been a collapse of the lumen. Elasticity and rigidity of the prefabricated trachea (those will later be evaluated quantitatively in macroscopical examination after sacrifice of animals) found to be satisfactory and the epithelial graft in the lumen was 100% viable in all animals (Fig. 3b). The thickness of the walls and the diameter of the lumen were similar to the native trachea. After evaluation, 2 cm long circumferential resection of the native trachea is performed and
prefabricated neotrachea is adapted to the defect. First proximal and then the distal anastomosis is performed. Six 6/0 polypropylene sutures are used for each anastomosis. Since polypropylene mesh skeleton is embedded between fascia and epithelial graft, it is not exposed at the anastomosis sites. To prevent air leakage from the lumen fibrin glue is applied to the anastomosis sites and anastomosis is completed. Atropine and dexamethasone sulfate is injected to all animals intraoperatively to decrease secretions and edema. Intramuscular ampicillin sulbactam is applied in the first 2 weeks after anastomosis. Evaluation after anastomosis has been done in five ways: (1) The rabbits were evaluated clinically for 4 weeks post operatively for their respiration and wound healing. (2) Computed tomography is performed 2 weeks after the anastomosis to assess the patency of the lumen. (3) At the fourth week of anastomosis before sacrifice of the animals, the neotrachea is dissected and viability of neotrachea and patency of vascular pedicle is inspected. The animals have been sacrificed 4 weeks after the anastomosis and tracheal tree is imaged by radiopaque solution to assess air tightness.
Reconstruction of circumferential trachea
Fig. 4
339
Incision of the reconstructed trachea sagittally to inspect the lumen.
(4) Macroscopical examination: whole larynx, trachea, lungs and pedicle is excised to evaluate the rigidity and longitudinal elasticity. Rigidity (resistance to collapse) is measured by a dynamometer and compared to that of the mean value of native tracheas. Longitudinal elasticity of each neotrachea is measured in degrees and compared to mean of the rabbits native tracheas (same length). The measurement is done by fixing one end of the neo trachea with a forceps and bending the other side with another forceps. The maximum possible bending in degrees that did not produce collapse of the lumen is measured. Then to inspect the lumen and epithelial graft, the trachea is incised sagitally (Fig. 4). (5) Histological examination is done in sections of three levels: first at the level of anastomosis, second at the level of prefabricated trachea and third at the level of the normal trachea. The specimens were fixed with 5% glutaraldehyde and stained with hematoxylin-eosin.
3. Results The rabbits were evaluated clinically for their respiration and healing of the operation fields. In all rabbits, there was no problem in donor sites of the hairless epithelial graft. Three days after the second stage (prefabrication), two animals had partial skin necrosis and detachment in their abdominal incisions. These two animals are reoperated and debrided but one of them had died due to infection at the end of the second week (before the anastomosis). Its prefabricated trachea has been biopsied for histological examination. The other animal has improved and included to the third stage (anastomosis). There was no wound-healing problem in other animals. Remaining nine animals had mild wheezing in the first week after the anastomosis, but three of them had stridor and respiratory insufficiency at the end
of the first week after the anastomosis. One of them had died 7 days after the anastomosis. Its trachea was included in macroscopic and histological examinations. In the macroscopic examination of this animal, there was no occlusion in the lumen of the prefabricated trachea. The lumen was covered by viable hairless epithelial graft and the anastomoses were intact. Therefore, we think that aspiration of blood or fibrin glue during the anastomosis might have caused problem in the lower respiratory tract. Pathologic examination did not reveal valuable information about the reason of death. The other two animals gradually improved and sacrificed by us. One of the remaining eight animals, which had no problem before, had an acute respiratory insufficiency and stridor at the 11th day after anastomosis. It has not improved despite orotracheal aspiration. Therefore, it has been reoperated for exploration and died during the operation. In the exploration, it was seen that there has been a partial detachment in the proximal anastomosis and the lumen was occluded by neighboring tissues. The reason for the detachment was the shortness of the pedicle in this particular animal, which did not permit the animal for normal neck movements, and the tension probably caused the detachment. The trachea of this animal was included in the study. Subcutaneous emphysema was seen only in this animal, which assures that fibrin glue prevented the air leakage during the healing process in other animals. In summary, three of the 10 animals have been lost. One from wound infection before the anastomosis, second from unproved lower respiratory tract problems 7 days after anastomosis and third from detachment in the proximal anastomosis 11 day after anastomosis.
3.1. Computed tomography Two weeks after the anastomosis, surviving seven animals were evaluated by computed tomography.
340
A. Okumus¸ et al.
Fig. 5 (a) Sagittal plane views of trachea. The arrows indicate the anastomosis sites of prefabricated neotrachea. (b) Image of prefabricated neotrachea with radiopaque solution. Metal pins indicate boundaries of prefabricated neotrachea.
There has been a 20% (1 mm) narrowing of the prefabricated tracheal segment in two of the rabbits. There was no difference in the diameter of the prefabricated tracheal and native tracheal lumen in the other five animals. The sagittal plane views showed no occlusion or early stricture (Fig. 5a).
3.2. Imaging prefabricated trachea with radiopaque solution At the end of fourth week after the anastomosis, the animals were anesthetized and prefabricated neotrachea was dissected for evaluation of vascular
pedicle patency and flap viability by inspection (Table 1). Later animals were sacrificed by high dose phenobarbital. Before excising the trachea for macroscopical and histological examination, meglumin amidotrizoat (radiopaque solution) is injected through dissected cricothyroid membrane into the tracheal lumen and plain X-rays were obtained (Fig. 5b). In this examination, the tracheal lumen was found to be normal in both anastomosis sites and through the prefabricated neotrachea and there was no leakage of the radiopaque solution from the anastomosis in any animal that assures airthightness.
Rabbits
1 2 3 4 5 6 7 8
9 10
Survey
Viability of neotrachea
Patency of vascular pedicle
Viability of skin graft
Longitidunal elasticity N: 508 ( 4.3) measured in degree
Luminal features
Hair growth
Rigidity N: 39 ( 1.2) measured in bars
Sacrificed 4 weeks after anastomosis Died before anastomosis Sacrificed 4 weeks after anastomosis Died 1 week after anastomosis Sacrificed 4 weeks after anastomosis Sacrificed 4 weeks after anastomosis Sacrificed 4 weeks after anastomosis Died 11 days after anastomosis
Viable
Patent
100% Viable
498
No hair growth
41
No necrosis
Could not be evaluated Patent
No necrosis
518
No hair growth
42
100% Viable
548
No hair growth
41
No hair growth
42
No hair growth
40
No hair growth
41
No hair growth
42
No hair growth
42
Sacrificed 4 weeks after anastomosis Sacrificed 4 weeks after anastomosis
Diameter 4 mm, no collapse Diameter 5 mm, no collapse Diameter 4 mm, no collapse Diameter 5 mm, no collapse Diameter 5 mm, no collapse Diameter 5 mm, no collapse Diameter 5 mm, no collapse The lumen was occluded by neighboring tissue Diameter 5 mm, no collapse Diameter 5 mm, no collapse
No hair growth
42
No hair growth
41
Viable No necrosis
No necrosis
508
Viable
Could not be evaluated Patent
100% Viable
528
Viable
Patent
100% Viable
488
Viable
Patent
100% Viable
528
No necrosis
Could not be evaluated
No necrosis
508
Viable
Patent
100% Viable
528
Viable
Patent
100% Viable
498
Reconstruction of circumferential trachea
Table 1 Results
N: mean value and standart deviation for native tracheas.
341
342
A. Okumus¸ et al.
3.3. Macroscopical examination After imaging with radiopaque solution the trachea is irrigated by saline solution for cleaning the radiopaque solution and then whole larynx, trachea, pedicle and lungs were excised for macroscopic examination. The longitudinal elasticities were similar to native tracheas (Table 1). The dynamometric measurements for rigidity of neotrachea were a bit higher than native trachea (Table 1). Later the tracheal tree is incised sagittally (Fig. 4) to inspect epithelial graft viability, anastomose healing and any probable hair growth. It is seen that 100% of the epithelial graft survived and the anastomosis sites healed perfectly except for the animal which died 11 days after anastomosis due to detachment of proximal anastomosis. There was no hair growth or granulation tissue in any of the animals (Table 1).
3.4. Histological examination The thicknesses of the walls were similar and the lumen of the prefabricated trachea was lined with a viable stratified squamous epithelium in all sections (Fig. 6). There were no hair follicles in the sections. The anastomosis was well healed and there has not been exposition of polypropylene mesh through the anastomosis sites. In the prefabricated trachea, strong fibrovascular attachments were found between lateral thoracic fascia and epithelial graft. This strong structure explains the stability of tracheal wall components and explains how 100% of the epithelial grafts in all animals survived. No metaplastic changes were observed in squamous epithelium to be transformed into columnar epithelium. Fig. 6 Histologic sections of native (a) and prefabricated (b) trachea. The arrows in prefabricated trachea indicate the polypropylene mesh and strong fibrovascular attachments through its porous network.
4. Dicussion As pointed out by Belsey [6] ideal trachea reconstruction should have these basic properties: (a) (b) (c) (d)
lateral rigidity; vertical elasticity; airtight lumen; continuous internal mucosa; (e) reliable healing.
lining
of
respiratory
Partial thickness and non-circumferential full thickness tracheal defects have been reconstructed by autologous tissues successfully [4,7,8] but reconstruction of wide circumferential tracheal defects is still an unsolved problem [1,3,9,10]. Even if both stumps are mobilized as much as possible end-to-
end primary anastomosis is impossible in defects more than half of the tracheal length [1]. In conditions with long tracheal resections, prosthesis replacement is preferred to mediastinal tracheaostomy, which has high complication rates but this not an ideal reconstruction. Lots of methods and materials have been proposed for trachea reconstruction and the success is limited. Synthetic materials such as hydroxiapatite, dacron, polyurethane, polytetrafluorethane have been used but all lead the surgeons to disappointment [11,12]. The disadvantages of these reconstruction methods are; lack of blood circulation, inflammatory reactions and resulting failure of
Reconstruction of circumferential trachea
anastomosis, infection and probable exposition. Moreover, lack of epithelial lining causes ingrowth of granulation tissue into the lumen resulting occlusion of lumen or stenosis. Autografts either single (cartilage, perichondrium and periosteum) or combined (cartilage/perichondrium, cartilage/mucosa) have been tried [4,13,14]. The problem with these alternatives is not only the lack of optimal circulation that causes bad results but also limited donor sites. Perichondrial and periosteal grafts are not rigid enough. The production of cartilage or bone, which will give rigidity, takes time and these grafts need stent until gaining their own rigidity. The stent commonly causes inflammation and necrosis. Moreover, the produced cartilage or bone can grow into the lumen and causes obstruction or narrowing of the lumen. Compared to synthetic and autologous grafts, axial flaps causes minimal inflammation and by their rich blood supply, they provide optimal circulation to the anastomosis healing, Many axial flaps such as sternocleidomastoid muscle containing clavicular periosteum [16] or pectoralis major [15] muscle have been proposed for tracheal reconstruction. Both of these methods have the disadvantage of lack of skeleton and epithelial lining. To solve these problems, intercostal muscle flap [17] raised with cartilage and combined with skin graft have been defined but this method could not find proponent due to high rate of complications and mortality. Axial or free jejunal flaps either alone [18] or combined with a skeleton (cartilage or synthetic graft) is used [3] but peristalsis and secretions have been a problem also laparotomy and enterectomy brings out additional risks. Prefabrication used with axial flaps enables combinations of tissue and synthetic materials with desired biologic and physical features. Many prefabricated flaps have been defined in animals for reconstruction of trachea. Ruuska ¨nen et al. [19] prefabricated Perichondrial flaps to form cartilaginous tubes. Fayad and Kuriloff [20] prefabricated well-vascularised axial muscular flap tubes supported by collagen and morphogenetic protein. All the explained flaps have optimal circulation and rigidity but lack in epithelial lining. Cadavas [3] prefabricated an axial composite flap consisting of skin, cartilage and mucosa, which provides epithelial lining, but the method is complicated and requires multiple procedures. Lykoudis et al. [2] defined an axial prefabricated flap containing an epithelial lining reinforced with synthetic materials but since they did not perform anastomosis, the success of the flap could not be evaluated without the use of stent. Suh et al. [21] prefabricated a well vascularised polypropylene mesh lined with oral mucosa. Their
343
study fulfills the needs for ideal circumferential trachea reconstruction. However, they used omentum as a vascular supply, which will need laparotomy for prefabrication. We think that lateral thoracic fascia with its pedicled fashion is superior to omentum. For inner epithelial lining, we tried oral mucosa of the rabbit first but enough mucosa could not be harvested so proximal inner ear is selected as donor site of epithelial lining. Vascular carrier is chosen as the lateral thoracic fascia, which is well vascularised and has a long pedicle that enables wide arc of rotations. Both cervical and mediastinal trachea can be reconstructed without traction of the pedicle. Polypropylene mesh is used as the skeletal framework. It elicits minimal inflammatory response and has minimal risk of migration when used for abdominal wall reconstruction or as a suture material. Its network allows cellular infiltration and strong adherence of two tissues that it is found between. Therefore, it enables a strong and thin tissue combination. It has not only vertical and horizontal elasticity similar to trachea but also excellent rigidity. Potential limitations of this study are the lack of long-term results. Complications such as strictures, probable hair growth in long term and probable possession of sebaceous, sweat glands by the skin graft and probable accumulation of secretions due to lack of ciliary function, needs longer term follow up for evaluation. However, it is known that lack of epithelial lining that result in granulation formation is the main reason of strictures. Since our epithelial grafts were viable in all animals, we do not expect stricture. Consequently, no stricture was observed in 6 months follow up in the study of Suh et al. [21], which was designed in a similar fashion. Moreover, Suh et al. [21] reports that squamous epithelium was transformed into ciliated columnar epithelium in 6 months in their dog model. This experimental study has some superiority to the other reconstruction methods. All surgical procedures take place in the subcutaneous plane that is easily handled and accessed. Minimal donor field morbidity is achieved. None of the functional elements of body such as muscle, cartilage or bone is used. Since the flap is thin and similar to trachea, there is no bulky tissue in the neck so the aesthetic result is good.
References [1] H.C. Grillo, Circumferential resection and reconstruction of the mediastinal and cervical trachea, Ann. Surg. 162 (1965) 374—387. [2] E.G. Lykoudis, D.A. Tsoutos, A.E. Papalois, K.B. Frangia, C.N. Stamatopoulos, J.D. Ioannovich, Prefabrication of an axial
344
[3]
[4]
[5] [6] [7]
[8]
[9]
[10]
[11]
[12]
A. Okumus¸ et al.
bio-synthetic flap for circumferential tracheal defect reconstruction, Br. J. Plast. Surg. 53 (2000) 508—515. P.C. Cavadas, Tracheal reconstruction using a free jejunal flap with cartilage skeleton: experimental study, Plast. Reconstr. Surg. 101 (4) (1998) 937—942. P.R. Delaere, R. Hermans, J. Hardillo, BV.D. Hof, Prefabrication of composite tissue for improved tracheal reconstruction, Ann. Otol. Rhinol. Laryngol. 110 (2001) 849—860. R.K. Khouri, J. Upton, W.W. Shaw, Principles of flap prefabrication, Clin. Plast. Surg. 19 (1992) 763—771. R. Belsey, Resection and reconstruction of the intrathoracic trachea, Br. J. Surg. 38 (1951) 200—205. B.G. Narodick, L.W. Worman, A.H. Pemberton, Relaxation technique for tracheal reconstruction, Ann. Thoracic. Surg. 1 (1965) 190—196. E.W. Fonkalsrud, W.G. Plested, D.G. Mulder, Tracheobronchial reconstruction with autologous periosteum, J. Thoracic. Cardiovas. Surg. 52 (1966) 666—674. J.P. Neifeld, S.D. Theogaraj, A.I. mehrhof, Reconstruction after mediastinal tracheostomy, Am. J. Surg. 148 (1984) 505—508. A. Yamada, K. Harii, Y. Itoh, T. Kikawada, H. Miyashita, Reconstruction of the cervical trachea with a free forearm flap, Br. J. Plast. Surg. 46 (1993) 32—35. H.F. Biller, M.A. Munier, Combined infrahyoid and inferior constrictor muscle release for tension-free anastomosis during primary tracheal repair, Otolaryngol. Head Neck Surg. 107 (1992) 430—433. A. Shaha, T. Dimaio, S. Money, Y. Krespi, M.B. Jaffe, Prosthetic reconstruction of the trachea, Am. J. Surg. 156 (1988) 306—309.
[13] T.J. Krizek, J.A. Kirchner, Tracheal reconstruction with an autogenous mucochondrial graft, Plast. Reconstr. Surg. 50 (1972) 123—130. [14] L. Ohlsen, U. Nordin, Tracheal reconstruction with perichondrial grafts: an experimental study, Scand. J. Plast. Reconstr. Surg. 10 (1976) 135—145. [15] A. Fleischer, R. Khafif, Reconstruction of the mediastinal trachea with a tubed pectoralis major myocutaneous flap, Plast. Reconstr. Surg. 84 (1989) 342—346. [16] M. Freidman, A.D. Mayer, Laryngotracheal reconstruction in adults with sternocleidomastoid myoperiosteal flap, Ann. Otol. Rhinol. Laryngol. 101 (1992) 897—904. [17] C. Papp, J.B. McCraw, P.G. Arnold, Experimental reconstruction of the trachea with autogenous materials, J. Thorac. Cardiovasc. Surg. 90 (1985) 13—20. [18] R.E. Jones, R.F. Morgan, K.L. Marcella, S.E. Mills, I.L. Kron, Tracheal reconstruction with autogenous jejunal microsurgical transfer, Ann. Thorac. Surg. 41 (1986) 636— 638. [19] M.M. Ruuska ¨nen, M.J. Kallioinen, O.I. Kaarela, J.A. Laiho, P.O. To ¨la ¨, T.J. Waris, The role of polyglycolic acid ¨rma rods in the regenerations of cartilage from perichondrium in rabbits, Scand. J. Plast. Reconstr. Hand. Surg. 25 (1991) 15—18. [20] J. Fayad, D.B. Kuriloff, Prefabricated microvascular autograft in tracheal reconstruction, Otolaryngol. Head. Neck. Surg. 111 (1991) 396—406. [21] S.W. Suh, J. Kim, C.H. Baek, J. Han, H. Kim, Replacement of a tracheal defect with autogenous mucosa lined tracheal prosthesis made from polypropylene mesh, ASAIO J. 47 (5 (September—October)) (2001) 496—500.
