Chondrocyte viability in human nasal septum after morselization

Sliced vs crushed cartilage for camouflage: long-term graft survival and histological outcomes

PURPOSE

In this study, we proposed a "sliced-partial thickness cartilage graft" for nasal contour restoration purposes and compared the long-term graft survival and histological changes of sliced, crushed, and intact cartilage grafts.

METHODS

Nasal septal and auricular cartilage grafts were harvested from 8 rabbits. Sliced, crushed, or intact cartilage grafts were measured in thickness with a micrometer and re-implanted. 4 months later, specimens were histologically evaluated and thickness were measured.

RESULTS

Both nasal septal and auricular crushed cartilage lost significantly more chondrocytes than sliced samples together with fibrosis, multiple fracture lines, and even ossification. Sliced and intact cartilages were histologically similar except sliced cartilage had some minor changes limited to its cut surface. Sliced cartilages retained their thickness, histology, and structural properties in the long term similar to intact cartilages whereas -contrary to expectations- crushed specimens had significantly higher thickness measurements at the end of 4 months.

CONCLUSION

Sliced cartilage grafts prepared with an atraumatic cartilage slicer are an ideal camouflaging material with its uniform thickness, and malleability. Crushed cartilages seemingly getting thicker without histological findings could be explained by lower than actual initial measurements due to its structural weakness and getting squeezed when the standard pressure of the micrometer was applied.

Characterization of Injury Induced by Routine Surgical Manipulations of Nasal Septal Cartilage

Importance

This study characterizes and compares common surgical manipulations' effects on septal cartilage to understand their implications for rhinoplasty outcomes based on cell viability and cartilage health.

Objective

To illustrate distinct differences in the impact of various surgical manipulations on septal cartilage in an in vitro septal cartilage model. A secondary objective is to better understand the chondrocyte's response to injury as well as how alterations in the extracellular matrix correspond to chondrocyte viability.

Design, Setting, and Participants

In this bench-top in vitro porcine model using juvenile bovine septal cartilage from bovine snouts, easily obtainable septal cartilage was used to generate large numbers of homogenous cartilage specimens. Quantitative outcomes at early and late time points were cell viability, cell stress, matrix loss, and qualitative assessment through histologic examination. The study was performed at a single academic tertiary care research hospital.

Interventions

Four common surgical manipulations were contrasted with a control group: crushed cartilage, scored cartilage, diced cartilage, and shaved cartilage.

Main Outcomes and Measures

Following the manipulation of the cartilage, the quantitative outcomes were glycosaminoglycan release to the media, lactate dehydrogenase release to the media, and cell death analysis through apoptosis staining. The qualitative outcomes were histologic staining of the manipulated cartilage with safranin-O/fast green stain to identify proteoglycan loss.

Results

The crushing followed by shaving manipulations were the most damaging as indicated by increased levels of lactate dehydrogenase release, glycosaminoglycans loss, and cell death. Matrix loss did not increase until after 48 hours postinjury. Furthermore, chondrocyte death was seen early after injury and accelerated to the late time point, day 9, in all manipulations. Conversely, cell stress was found to be greater at 48 hours postinjury, which then declined to the late time point, day 9.

Conclusions and Relevance

The crushing manipulation followed by shaving and then dicing were the most destructive methods of cartilage manipulation relative to control specimens. Collectively, these outcomes demonstrate the range of injury which occurs with all septal cartilage manipulations and can inform rhinoplasty practice to use the least damaging effective surgical manipulation to obtain the desired outcome.

Level of Evidence

NA.

Puzzle-Formed Modified Turkish Delight for Nasal Dorsum Augmentation

Structural deficiencies of the nasal dorsum are most commonly of congenital, traumatic, or iatrogenic etiology. Various grafts, including autografts, homografts, and synthetic materials, have been used to this end and are described in the literature.Autologous septal cartilage is the most commonly used graft material when limited augmentation rhinoplasty is planned. However, it is difficult to retain sufficient cartilage to allow of such augmentation in instances where most of the septal cartilage has been used. The authors place moderately crushed cartilage beneath a monolayer of surgicel when performing limited nasal dorsum augmentation. The aim of the present study is to describe authors' approach and its utility by reviewing other methods reported in the literature.

Combined use of scoring incisions and 2-octylcyanoacrylate adhesive during endonasal septoplasty to correct cartilaginous deviations

BACKGROUND

Applying 2-octylcyanoacrylate (2-OCA) tissue adhesive onto scoring incisions may increase efficacy and prevent concavity recurrence after septal deviation treatment. The present study evaluates the utility of 2-OCA adhesive application during endonasal septoplasty.

METHODS

The postoperative outcomes were compared between two consecutive periods in a single surgical department. Between March 2011 and March 2012, 23 consecutive patients underwent septoplasty using scoring incisions without 2-OCA application (scoring alone group), and between April 2012 and April 2013, the scoring incision gaps were filled with 2-OCA in 27 patients (scoring + CA group). The patients were followed up for more than six months.

RESULTS

A straight septum was achieved in 37.0% of patients in the scoring alone group versus 58.3% in the scoring + CA group. The postoperative symptom score for nasal obstruction was significantly improved in both groups. Persistent septal swelling developed in three (12.5%) patients in the scoring + CA group. Neither group experienced major complications such as septal hematoma, abscess, or septal perforation.

CONCLUSIONS

Application of 2-OCA adhesive onto scoring incisions appears to be a reliable and effective technique to correct deviated cartilage during endonasal septoplasty. However, the volume of 2-OCA applied onto the septum should be minimized to avoid potential foreign body reaction. A long-term follow-up study is warranted.

Dorsal nasal augmentation with "open sandwich" graft consisting of conchal cartilage and retroauricular fascia

BACKGROUND

Augmenting the nasal dorsum with conchal grafts can cause visible irregularities over time due to the morphological qualities of that material.

OBJECTIVES

This study describes the senior authors' technique of dorsal nasal augmentation with chondrofascial "open sandwich" grafts consisting of pieces of conchal cartilage and retroauricular fascia. The authors assess the efficiency and reliability of this graft in nasal dorsal augmentation.

METHODS

The authors retrospectively reviewed the cases of 19 patients who underwent dorsal augmentation rhinoplasty with chondrofascial grafts. Both cartilage and fascia were harvested through the same incision in the retroauricular sulcus. The conchal graft was cut in 2 to 4 pieces and slightly crushed with tissue forceps. The pieces of cartilage were arranged and fixed to the fascia in different patterns according to the nasal dorsum contour.

RESULTS

The follow-up period ranged from 12 to 35 months in 16 patients who qualified for inclusion in the final data. The maximal thickness of the chondrofascial graft was 4.5 mm. There were no major complications in the recipient area, except 1 case of undercorrection. There were 2 complications in the donor area. In 1 case, a hematoma was treated conservatively. In another case, a strip of skin necrosis in the conchal area occurred and was treated by excision and direct suture with satisfactory resolution.

CONCLUSIONS

The autologous chondrofascial graft is appropriate for slight to mild dorsal nasal augmentation. The method, as with most rhinoplasty techniques, requires careful and judicious preoperative examination, planning, and execution. The postoperative scar is inconspicuous and the donor site morbidity is minimal.

Needle electrode-based electromechanical reshaping of rabbit septal cartilage: a systematic evaluation

Electromechanical reshaping (EMR) provides a means of producing shape change in cartilage by initiating oxidation-reduction reactions in mechanically deformed specimens. This study evaluates the effect of voltage and application time on specimen shape change using needle electrodes. Rabbit septal cartilage specimens (20 x 8 x 1 mm, n = 200) were bent 90 degrees in a precision-machined plastic jig. Optimal electrode placement and the range of applied voltages were estimated using numerical modeling of the initial electric field within the cartilage sample. A geometric configuration of three platinum needle electrodes 2 mm apart from each other and inserted 6 mm from the bend axis on opposite ends was selected. One row of electrodes served as the anode and the other as the cathode. Constant voltage was applied at 1, 2, 4, 6, and 8 V for 1, 2, and 4 minutes, followed by rehydration in phosphate buffered saline. Samples were then removed from the jig and bend angle was measured. In accordance with previous studies, bend angle increased with increasing voltage and application time. Below a voltage threshold of 4 V, 4 minutes, no clinically significant reshaping was observed. The maximum bend angle obtained was 35.7 ± 1.7 º at 8 V, 4 minutes.