Medium term fate of cartilage grafts from children after laryngo-tracheoplasty

Rhinosurgery in children: developmental and surgical aspects of the growing nose

The anatomy of the nasal skeleton in newborns and adults are not alike. The complete cartilaginous framework of the neonatal nose becomes partly and gradually ossified during the years of growth and is more vulnerable to trauma in that period. Injury in early youth may have large consequences for development and may result in a nasal deformity which will increase during growth and reach its peak during and after the adolescent growth spurt. To understand more of the underlying problems of nasal malformations and their surgical treatment (septorhinoplasty) these items became the focus of multiple animal studies in the last 40 years. The effects of surgery on the nasal septum varied considerably, seemingly depending on which experimental animal was used. In review, however, the very different techniques of the experimental surgery might be even more influential in this respect. Study of one of the larger series of experiments in young rabbits comprised skeletal measurements with statistical analysis, and microscopic observations of the tissues. The behaviour of hyaline cartilage of the human nose appeared to be comparable to that of other mammals. Cartilage, although resilient, can be easily fractured whereas its tendency to integrated healing is very low, even when the perichondrium has been saved. Also surgical procedures - like in septoplasty - may result in growth disturbances of the nasal skeleton like recurrent deviations or duplicature. Loss of cartilage, as might occur after a septum abscess, is never completely restored despite some cartilage regeneration. In this article experimental studies are reviewed and compared.Still there remains a lack of consensus in the literature concerning the developmental effects of rhinosurgry in children.Based on their observations in animals and a few clinical studies, mostly with small numbers of patients but with a long follow-up, the authors have compiled a list of guidelines to be considered before starting to perform surgery on the growing midface in children.

Meyer procedure for severe laryngotracheal stenosis

Many surgical procedures have been devised to manage laryngotracheal stenosis secondary to trauma. Laryngotracheal atresia is the most severe form and the most difficult to repair. The Meyer procedure is a three-stage operation that provides structural support that is covered with mucosa. A laryngotracheal trough is created and a carved trough-shaped cartilage graft is placed above and lateral to it in the first stage. The skin over the graft is replaced by buccal mucosa in the second stage. In the last stage, the cartilage graft with overlying mucosa is swung onto the trough as a composite flap replacing the anterior and lateral laryngeal and tracheal walls. Attempt at reconstruction was made in 8 patients. All but one lesion was secondary to endotracheal intubation. Two patients were unable to be taken to completion of the third stage. Of the remaining 6 patients, all have a functional voice and only 1 remains cannulated at night.

Wound healing of cartilage structures in the head and neck region

This study was performed to determine the various processes involved in the behaviour of hyaline cartilage during the wound healing period after trauma or surgery of vulnerable structures like the nasal septal cartilage and the cricoid. The results of different procedures (perpendicular and parallel to the cartilage surface) in young and young-adult animals were analyzed: septal incision at different locations (young-old), cricoid split (young-old), suturing cartilage, closing defects with autologous cartilage (young), biomaterials (young) and newly engineered cartilage in 4- and 24-week-old rabbits (series of ten animals). Cartilage of the young rabbit and child have similar hyaline cartilage with a varying distribution in thickness. Thinner areas are more susceptible to malformations. Incisions through younger cartilage give rise to some new cartilage formation covered by a new layer of perichondrium: through older, differentiated cartilage the incision causes superficial but permanent necrosis. Edges of cut cartilage mostly do heal by formation of fibrous junctions. This forms a weak spot, sensitive to deviations. The same fate goes for the healing between the autologous graft and the surrounding pre-existent cartilage. Trauma parallel to the surface, leads to inconsistent quantity of neocartilage. With ageing the wound healing and regenerative capacities decrease. In general, biomaterials are less accepted by the surrounding tissues and would impede further growth. Only newly engineered, and thus less differentiated (younger) cartilage of hyaline nature, appeared to be well accepted at the interface with the edges of a cartilage defect. There are indications that the release of growth factors might play a role in cartilage wound healing. In the child as well as the adult, wound healing of hyaline cartilage structures is incomplete, and surgery remains 'experimental' surgery. The clinical implications of gradual loss of the regenerative capacity of hyaline cartilage should be further investigated.

Acquired laryngeal stenosis in infants and children treated by laryngofissure and stenting

Thirty young patients with acquired laryngeal stenosis were treated by means of a laryngofissure and stenting. The age distribution suggested two subgroups: infants aged 0-2 years (n = 24), and children aged 6-16 years (n = 6). The causes of the stenosis and the treatment results were different in these subgroups. Treatment resulted in successful decannulation in 22 of 24 infants, and in 5 of 6 children. Treatment included a re-operation in two patients. In 1 patient the therapy failed, and 2 patients died after fatal complications. Decannulation rate, duration of the tracheotomy, and the number of re-operations compare favorably to the results of other centers. The longer duration of stenting, and the high mortality rate may be considered disadvantages.

Long-term airway considerations after treatment of severe pediatric laryngotracheal stenosis in five children

After initial treatment of severe laryngotracheal stenosis (LTS), we evaluated subsequent airway function. Five children between 2 and 11 years were treated previously for severe LTS by T-tube stenting. One case underwent subsequent laryngotracheal reconstruction. All patients demonstrated dyspnea, the severity of which increased with age and duration of time after completion of stenosis treatment. In the most severe cases, magnetic resonance imaging and endoscopy revealed secondary subglottic stenosis. Ventilatory function tests disclosed obstruction of both extrathoracic and pulmonary origin. These findings raise questions regarding the treatment of the initial stenosing tissue and of the secondary stenoses.

Cartilage transformation in a composite graft of demineralized bovine bone matrix and ear perichondrium used in a child for the reconstruction of the nasal septum

For the first time it was observed in a boy that a xenogenic implant of demineralized bovine bone matrix, enfolded in a pedicled flap of autogenic ear perichondrium, was transformed into autogenic cartilage. This new cartilage could be adequately used as a graft to bridge the cartilaginous defect of a nasal septum perforation. The defect was successfully closed by a technique employing four bipedicled mucosal advancement flaps of the septum and the nasal floor. The result of this pilot study, which is based on experiments in growing rabbits, appears to open the possibility to create de novo young and growing autogenic cartilage of substantial quantity in children, without the loss of the cartilage present.