Histological structure of the nasal cartilages and their perichondrial envelope. II. The perichondrial envelope of the septal and lobular cartilage

The perichondrial envelopes of the septal cartilage and the lateral crus of the lobular cartilage were studied in serial coronal sections of five human noses. To differentiate between the various tissue components, the sections were stained according to Mallory-Cason, Azan, Herovici, Verhoeff-van Gieson, and Lawson. Collagen types I and II were immunohistochemically stained. The results demonstrated that the perichondrium of the septal cartilage and the lateral crus of the lobular cartilage consists of a homogeneous layer of type I collagen fibers and elastic fibers. The elastic fibers have a network-like arrangement and are most numerous in the perichondrium of the lateral crus of the lobular cartilage. Clearly distinguishable zones in the perichondrial envelopes could not be observed. The perichondrium on the outside of the lateral crus of the lobular cartilage and the triangular cartilage is significantly thicker than the inner perichondrium. It is speculated that these morphological characteristics of the perichondrial envelopes are related to functional differences between the cartilages. The mobility of the lateral crus of the lobular cartilage requires a higher content of elastic fibers in its perichondrium than the more rigid septal cartilage. A thicker outer perichondrium of the lateral crus of the lobular cartilage and the triangular cartilage may be related to muscular forces that are exerted on the outer side of the cartilages only.     

Posterior tragal perichondrium harvesting for myringoplasty

We present a modified harvesting approach for tragal perichondrium, used in tympanic membrane reconstruction. The technique described avoids amputation of the tragus thereby facilitating dissection of the perichondrium from the cartilage as compared to the traditional method. The approach described is technically easier, and removes any potential for cosmetic deformity associated with tragal cartilage amputation and reimplantation. Furthermore, both the anterior tragal perichondrium and the temporalis fascia remain intact if further surgery is required. We recommend this approach for permeatal, tragal perichondrial grafting of small to medium sized tympanic membrane perforations.     

Posterior tragal perichondrium harvesting for myringoplasty.

We present a modified harvesting approach for tragal perichondrium, used in tympanic membrane reconstruction. The technique described avoids amputation of the targus thereby facilitating dissection of the perichondrium from the cartilage as compared to the traditional method. The approach described is technically easier, and removes any potential for cosmetic deformity associated with tragal cartilage amputation and reimplantation. Furthermore, both the anterior tragal perichondrium and the temporalis fascia remain intact if further surgery is required. We recommend this approach for permeatal, tragal perichondrial grafting of small to medium sized tympanic membrane perforations.     

Neochondrogenesis in the septal area after submucous cartilaginous resection.

The present work was carried out to study cartilaginous repair after subperichondrial resection of the septal cartilage, the fibrous layer of the perichondrium remaining "in situ". In these conditions, after granulation tissue formation, both neochondrogenesis and connective tissue differentiation were observed. Neochondrogenesis was found in defect areas next to the resection borders, and connective tissue formation in those further away. The transition zone between both types of newly-formed tissues showed cells with intermediate characteristics of chondrocytes and myofibroblasts. The findings provide safer proof that new chondrocytes and fibroblasts growing after septal cartilage removal originate largely from a common precursor cell either in the fibrous perichondrial layer or in the connective tissue surrounding it. The peculiar topographic distribution of the newly-formed tissues may be explained by the different effects during respiration of mechanical forces on the septal space, which lacks its cartilaginous support, and on the adjacent remaining cartilage, as well as on the borders of both.     

Cartilage regeneration in the rabbit nasal septum

OBJECTIVE: Rhinoplasty frequently includes harvesting of nasal septal cartilage. The objective of this prospective basic investigation is to determine whether cartilage can regenerate after submucosal resection (SMR) of the nasal septum in the rabbit. Neocartilage formation has not heretofore been described in this model. METHODS: By lateral rhinotomy, SMR was performed on 17 rabbits followed by reapproximation of the perichondrium. After 7 months, septi were fixed, sectioned, and examined histologically. Findings were photographed and data tabulated according to location and extent. RESULTS: Sites of matrix-secreting isogenous chondrocyte islands were identified between the perichondrial flaps of every animal, principally in the anterior inferior septum. The width of the islands averaged 190 microm, and the mean neocartilage height was found to be 840 microm. The newly formed cartilage consisted of chondrocytes within chondrons and was comparable in shape and structure to native septal cartilage. CONCLUSIONS: After SMR, rabbit cartilage tissue can regenerate and form matrix within the potential space created by surgery. The surrounding stem cell-rich perichondrium may be the site of origin for these chondrocytes. These findings suggest that after SMR of the human nasal septum, it may be possible for new cartilage tissue to develop provided the mucosa is well approximated. This biologic effect may be enhanced by insertion of cytokine-rich tissue scaffolds that exploit the native ability of septal perichondrium to regenerate and repair cartilage tissue.     

Comparison of different tympanic membrane reconstruction techniques in type I tympanoplasty

The objective of the study was to assess the functional results after type I tympanoplasty with temporal muscle fascia, perichondrium/cartilage island and cartilage palisades. The records of 120 patients who underwent type I tympanoplasty operation between January 2003 and June 2007 were retrospectively reviewed. This study aimed to comprise a homogeneous group of patients to make the comparisons as accurate as possible. For this purpose, primary tympanoplasty cases with subtotal perforations, intact ossicular chain, dry ear for a period of at least 1 month, and normal middle ear mucosa were included in the study. Patients younger than 15 years of age and patients with cholesteatoma were excluded. Temporal muscle fascia was used in 67 (55.8%), perichondrium/cartilage island flap was used in 34 (28.3%), and cartilage palisades were used in 19 (15.8%) of the patients. Pre- and postoperative otoscopic examinations, pure-tone averages, and air-bone gaps were compared pre and postoperatively. Concerning all of the cases, the graft take rate was 85% (102/120). In the perichondrium/cartilage island flap group, the graft take rate was 97.7%, whereas the graft take rates for the fascia group and cartilage palisades group were 80.6 and 79.0%, respectively. In the perichondrium/cartilage island flap group, the pure-tone average was 36.36 dB, whereas the pure-tone averages for the fascia group and cartilage palisades group were 36.07 and 39.79 dB, preoperatively. The postoperative pure-tone averages were 24.54 dB fort he perichondrium/cartilage island flap group, 24.51 dB for the fascia group and 23.23 dB for the cartilage palisades group. Cartilage grafting is not only more enduring against infection and negative middle ear pressure but also it has low re-perforation rates on long-term follow-up. Thus, cartilage may be preferred more often for primary tympanoplasties with high graft rate and hearing improvement.     

Morphologic aspects of the injured nasal septum in children.

Biopsies from the septal cartilage in children have been examined histologically to study the influence of trauma, surgery, septal abscess, and transplantation on the growing cartilage. Loss of cartilage, complete, but mostly incomplete regeneration of the defects are the main reactions. A regenerative potential mainly arising from the perichondrium plays an important factor for restoring the septal structure, often in a deforming and excessive way. Even preserved cartilage implanted immediately into the septal abscess, may be transformed into autogenous cartilage if the perichondrium is preserved.     

Viability and Regeneration of Chondrocytes after Laser Cartilage Reshaping Using 1,460 nm Diode Laser

Objectives

Cartilage reshaping by laser irradiation is used to correct septal and auricular cartilage deformities. Chondrocyte viability following laser irradiation and reshaping has been well established. However, the regeneration process of chondrocyte after laser irradiation has not been revealed yet. The aims of this study were to determine the mechanism of cartilaginous thermal injury and the regenerative process of damaged cartilage following laser irradiation.

Methods

Laser irradiation was performed on human septal cartilage and rabbit auricular cartilage using a 1,460-nm diode laser. We observed change in the shape of cartilage and evaluated the extent of cartilage injury using live/dead cell assay via confocal microscopy. Hoechst and propidium iodide (PI) staining was used to evaluate the mechanism of chondrocyte injury after laser irradiation. To evaluate the regeneration of cartilage, laser irradiated cartilages were reimplanted into a subperichondrial pocket and were harvested at 1, 2, and 4 weeks after reimplantation for viability assessment and histologic examination.

Results

Laser irradiation using a 1,460-nm diode laser produced a marked shape change in both human septal and rabbit auricular cartilages. Thermal damage on cartilage was correlated with the exposure time and the laser power. Hoechst and PI staining showed that chondrocyte death by laser irradiation was due to mainly necrosis, rather than apoptosis. In lower power treatment group (0.3 W and 0.5 W), all the chondrocytes regenerated within 4 weeks, however, in 1 W treatment group, chondrocytes could not regenerate until 4 weeks.

Conclusion

Reshaping of cartilage using 1,460 nm diode laser was attained concurrently with the thermal injury to the chondrocytes. The extent of thermal damage on chondrocytes was dependent on the exposure time and the laser power and the damaged chondrocytes irradiated with lower level of laser power could be regenerated after reimplantation into subperichondrial pocket.     

Autografts of uncrushed and crushed bone and cartilage. Experimental observations and clinical implications.

This study evaluated autografts of bone and cartilage, uncrushed and crushed, in the perichondrial space of the ear and subcutaneously in the paraspinal region in rabbits six weeks and six months after transplantation. The results support the belief that in a clinical setting it is important to preserve perichondrium because it facilitates growth of new cartilage. This study suggests that when autogenous tissue is to be used for subcutaneous augmentation, it is best to use crushed or uncrushed cartilage or uncrushed bone because they remain viable. In the perichondrial space, crushed and uncrushed cartilage grafts not only remain viable but also induce growth of new cartilage and bone. Autogenous crushed bone does not survive in the perichondrial space of the rabbit ear.     

Curving effect of scarification or unilateral perichondrial lining on septal cartilage from human autopsy material

From 20 cadavers septal cartilage was removed within 48 hours of death. From each cartilage four strips were prepared, two with preserved perichondrium on one surface and the other two not. On one strip from each group scarification was performed through about half the cartilage thickness. The curving of the cartilage strips was measured immediately after scarification and 5 h thereafter. The 17 mm. long strips showed a mean curving due to the scarification of 1.06 mm., 80 per cent of which occurred immediately after the scarification. It was demonstrated also that a unilaterally intact perichondrial lining per se entailed a curving averaging 0.52 mm., an effect which did not occur within the course of 5 h. Both effects were highly significant. It was not possible to demonstrate any correlation between these effects and donor age, cartilage thickness or orientation in the septum.     

Growth of the human septal cartilage: cell density and colony formation of septal chondrocytes

Human chondrocytes from 24 patients (5 to 52 years) with septal deviation were isolated in different areas of the septal cartilage. Cell density was counted, and the chondrocytes were grown in an assay system for determining the number of chondrocytes capable of proliferating. High cell density and excellent proliferative capacity were found in the anterior free end of the septal cartilage in all age groups. The central area showed the highest growth index in childhood, and increasing cell density from childhood to puberty. Generally the growth index decreased with age in all septal areas. The results help to explain some clinical observations: increasing septal cartilage even in adults, growth of nasal tip in adults, regenerative potential of septal cartilage after injuries or surgery, importance of the central area for septal growth and surgery.     

Pediatric auricular chondrocytes gene expression analysis in monolayer culture and engineered elastic cartilage

OBJECTIVES: This study was aimed at regenerating autologous elastic cartilage for future use in pediatric ear reconstruction surgery. Specific attentions were to characterize pediatric auricular chondrocyte growth in a combination culture medium and to assess the possibility of elastic cartilage regeneration using human fibrin. STUDY DESIGN: Laboratory experiment using human pediatric auricular chondrocytes. METHODS: Pediatric auricular chondrocytes growth kinetics and quantitative gene expression profile in three different types of media were compared in primary culture and subsequent three passages. Large-scale culture-expanded chondrocytes from the combination medium were then mixed with human fibrin for the formation of elastic cartilage via tissue engineering technique. RESULTS: The equal mixture of Ham's F12 and Dulbecco's Modified Eagle Medium (FD) promoted the best chondrocyte growth at every passage compared to the individual media. Chondrocytes differentiation index; ratio of type II to type I collagen gene expression level, aggrecan and elastin expression gradually decreased while passaging but they were then restored in engineered tissues after implantation. The engineered cartilage was glistening white in color and firm in consistency. Histological evaluation, immunohistochemistry analysis and quantitative gene expression assessment demonstrated that the engineered cartilage resemble the features of native elastic cartilage. CONCLUSION: Pediatric auricular chondrocytes proliferate better in the combination medium (FD) and the utilization of human fibrin as a biomaterial hold promises for the regeneration of an autologous elastic cartilage for future application in ear reconstructive surgery.     

Perichondrial flap to prevent chondritis and cartilage necrosis in salvage vertical partial laryngectomy for recurrent glottic carcinoma after irradiation: a new procedure

CONCLUSION: We conclude that our new closure method using the posterior- and inferior-based perichondrial flap may diminish the chance of development of chondritis in salvage vertical partial laryngectomized patients with recurrent glottic cancer. OBJECTIVE: Post-radiation laryngeal chondritis with resultant cartilage necrosis is one of the most dreaded complications of radiotherapy treatment of glottic carcinoma. In the case of salvage vertical partial laryngectomy, the risk of its development may be increased. We introduce a new posterior- and inferior-based perichondrial flap procedure to prevent postoperative chondritis after salvage vertical partial laryngectomy. MATERIAL AND METHODS: The perichondrium is incised along the midline and upper border of the thyroid cartilage, but not along the inferior border, unlike the conventional method. Then, the posterior- and inferior-based perichondrial flap, along with the cricothyroid muscle fascia, is elevated from the midline. For closure of the pharyngeal lumen, the outer perichondrium of the lesion side is sutured to the inner perichondrium of the contralateral side to protect the larynx from pharyngeal secretion. The utility of this procedure is reviewed retrospectively in 10 patients with locally persistent or recurrent squamous cell carcinoma of the vocal cord after failed laryngeal radiation therapy between 1994 and 2001. RESULTS: None of our patients developed chondritis postoperatively. The interval between the operation and removal of the tracheostomy tube ranged from 8 to 23 days (mean 12 days). Patients were able to swallow without aspiration within 7-22 days of the operation (mean 10 days). Discharge from hospital was possible after a mean recovery period of 11 postoperative days.     

甲壮软骨膜瓣再生软骨的实验观察

Cartilage regeneration was histologically evaluated in the pedicle thyroid perichondrial flaps bridging between the thyroid and the cricoid of 13 dogs. The result showed that the new cartilage presented mainly at the part of the pedicle end of the flap but disappeared gradually at middle part of the flap,and was replaced gradually by fibrosis from the pedicle end to the free end of the flap. It seemed that the perichondrial flap prossessed potential but limited capability of cartilage regeneration.     

Detection of class II antigens on human nasal cartilage

The presence and distribution of class II antigens on human nasal cartilage was investigated using monoclonal antibodies directed against HLA-DR, HLA-DP, and HLA-DQ molecules. Tissue sections and chondrocytes in suspension were prepared for immunoperoxidase staining and flow cytometric analysis. Class II antigens were detected primarily on the perichondrium. In contrast, chondrocytes, either isolated or in tissue sections, were completely negative, suggesting that cells of the perichondrium, may, by themselves, be capable of initiating a rejection process.     

Perichondrial flap to prevent chondritis and cartilage necrosis in salvage vertical partial laryngectomy for recurrent glottic carcinoma after irradiation: A new procedure

Conclusion

We conclude that our new closure method using the posterior- and inferior-based perichondrial flap may diminish the chance of development of chondritis in salvage vertical partial laryngectomized patients with recurrent glottic cancer.

Objective

Post-radiation laryngeal chondritis with resultant cartilage necrosis is one of the most dreaded complications of radiotherapy treatment of glottic carcinoma. In the case of salvage vertical partial laryngectomy, the risk of its development may be increased. We introduce a new posterior- and inferior-based perichondrial flap procedure to prevent postoperative chondritis after salvage vertical partial laryngectomy.

Material and methods

The perichondrium is incised along the midline and upper border of the thyroid cartilage, but not along the inferior border, unlike the conventional method. Then, the posterior- and inferior-based perichondrial flap, along with the cricothyroid muscle fascia, is elevated from the midline. For closure of the pharyngeal lumen, the outer perichondrium of the lesion side is sutured to the inner perichondrium of the contralateral side to protect the larynx from pharyngeal secretion. The utility of this procedure is reviewed retrospectively in 10 patients with locally persistent or recurrent squamous cell carcinoma of the vocal cord after failed laryngeal radiation therapy between 1994 and 2001.

Results

None of our patients developed chondritis postoperatively. The interval between the operation and removal of the tracheostomy tube ranged from 8 to 23 days (mean 12 days). Patients were able to swallow without aspiration within 7–22 days of the operation (mean 10 days). Discharge from hospital was possible after a mean recovery period of 11 postoperative days.     

A method for ossicular reconstruction with tragal cartilage autografts

Reconstruction of the ossicular mechanism using a tragal cartilage autograft frequently presents problems, including displacement of the cartilage graft, maintenance of firm and accurate contact between the graft and ossicular remnants, and loss of stiffness of the graft. To avoid these problems, we have used the cartilage graft and overlying perichondrium of appropriate size, with a tunnel made between the outer perichondrium and the cartilage to accommodate remnants of the incus or handle of the malleus. The graft has a small perichondrial flap on the other end for firm anchorage to the arch of the stapes or the footplate. This allows the cartilage graft to be firmly anchored with the adjacent ossicular remnants. The presence of perichondrium with the graft helps to maintain nutrition, stiffness, and the configuration of the cartilage. With minor modifications, we have used this technique in 115 patients to reconstruct different types of ossicular defects, with commendable hearing results. Of the 115 operated ears, an air-bone gap closure within 10 dB was found in 14.8%, within 15 dB in 34.8%, and within 20 dB in 24.4% of ears. In another 20.8% of cases, the air-bone gap closure remained in the range of 25 dB or less. The longest follow-up was 13 years 7 months. The presented technique is easy and effective and solves most of the problems of cartilage ossiculoplasty.     

甲状软骨膜瓣再生软骨的实验观察

为了解通过软骨膜再生软骨以修复软骨支架的可能性，使用１３只犬的甲状软骨膜瓣进行软骨再生的实验观察，发现软骨膜瓣有在的再生软骨的能力，在软骨膜瓣表达保留适当数量的软骨成分有助于软骨再生，但在常规方法下，春实际再生的软骨均十分有限