Stephen S. Park

Injectable Tissue-Engineered Bone Repair of a Rat Calvarial Defect

Advances in bone repair have focused on the minimally‐invasive delivery of tissue‐engineered bone (TEB). A promising injectable biopolymer of chitosan and inorganic phosphates was seeded with mesenchymal stem cells (MSCs) and a bone growth factor (BMP‐2), and evaluated in a rat calvarial critical size defect (CSD). Green fluorescent protein (GFP)‐labeled MSCs are used to evaluate patterns of cell viability and proliferation.

Clinical consensus statement: Diagnosis and management of nasal valve compromise

Objective: To create a clinical consensus statement to address ambiguities and disparities in the diagnosis and management of nasal valve compromise (NVC). Subjects and Methods: An updated systematic review of the literature was conducted. In addition, a Modified Delphi Method was used to refine expert opinion and facilitate a consensus position. Results: After two rounds of surveys and conference calls, 36 items reached consensus, six items reached near consensus, and 10 items reached no consensus. The categories that had the greatest percentage of consensus or near consensus items were as follows: definition, history and physical examination, outcome measures, and management. Conversely, the categories with greater percentage of no consensus items were adjunctive tests and coding. Conclusion: The consensus panel agreed that NVC is a distinct clinical entity that is best evaluated with history and physical examination findings. Endoscopy and photography are useful but not routinely indicated, whereas radiographic studies are not useful in evaluating NVC. Other objective nasal outcome measures may not be useful or accepted for NVC. Nasal steroid medication is not useful for treatment of NVC in the absence of rhinitis, and mechanical treatments may be useful in selected patients. Surgical treatment is the primary mode of treatment of NVC, but bill coding remains ambiguous and confusing.

Reconstruction of Nasal Defects Larger Than 1.5 Centimeters in Diameter

Objective To review the repair of larger nasal defects (>1.5 cm in diameter) and the vascular supply to the forehead flap.

FUNCTIONAL NASAL SURGERY

Functional nasal surgery is designed to repair nasal obstruction frequently caused by previous reduction rhinoplasty or blunt nasal trauma. Distinguishing the statically narrowed nasal valve from the weak sidewall with dynamic collapse is an important part of the preoperative evaluation. Our workhorse for repair of static obstruction is the combination of spreader grafts and flaring sutures, which together create a significant increase in the intranasal valve area. Dynamic collapse of the sidewall is corrected with cartilaginous batten grafts designed to increase sidewall rigidity. Less common causes of valve obstruction, such as tip ptosis, facial paralysis, cicatricial stenosis, Mohs reconstruction, and paradoxical lateral crura, are repaired by more individualized techniques.

Hyperbaric oxygen for the management of radionecrosis of bone and cartilage

Objectives: To review the use of hyperbaric oxygen in the management of radionecrosis of the head and neck. Study Design: A retrospective analysis of patients utilizing chart review and telephone interviews. All patients diagnosed with osteoradionecrosis and chondroradionecrosis of the head and neck and treated with hyperbaric oxygen at the University of Virginia are included. Methods: Demographics, pretreatment data, and precipitating events were recorded. Outcomes were evaluated using a grading scale of symptomatology and physical examination as determined by the patient and physician. Results: Sixteen patients with osteoradionecrosis and five with chondroradionecrosis were reviewed. All patients showed clinical improvement with decreased pain following HBO therapy. None of the patients with chondroradionecrosis required laryngectomies, and two of the four who were tracheotomy dependent were successfully decannulated. The patient and physician grading scores demonstrated moderate to significant improvement in both groups following therapy. Conclusion: The successful use of hyperbaric oxygen for the management of radionecrosis of the head and neck is supported. The unusual prevalence of chondroradionecrosis may be an early reflection of changes in treatment protocols for patients with head and neck cancer. Key Words: Hyperbaric oxygen, osteoradionecrosis, chondroradionecrosis.

Injectable Cartilage: Using Alginate and Human Chondrocytes

OBJECTIVE To create engineered cartilage through an injectable medium that could be used as a minimally invasive implant material. METHODS Human nasal septal chondrocytes, carried in an alginate polymer, were injected and molded percutaneously into nude mice and developed in vivo. The cartilage was harvested from 14 to 38 weeks and analyzed through gross, histological, immunohistochemical, and biochemical analysis. RESULTS Of the 15 explants, 14 (93%) resembled native cartilage on gross analysis. The injections maintained their overall appearance with some loss of definition. On histological analysis, 6 of the explants (40%) appeared similar to native cartilage throughout the sample. Eight of the explants (53%) resembled native cartilage; however, there were some areas of fibrous tissue differentiation. The neocartilage stained positive for type II collagen. Explants harvested at week 26 or later and the samples that histologically resembled native cartilage had similar hydroxyproline content to native septal cartilage. CONCLUSIONS Injectable, autologous cartilage may be the answer to the long search for the ideal implant in facial plastic surgery. Alginate and human chondrocytes can be used to create an injection that may be molded and maintains its overall size and shape, with some loss of definition, for at least 38 weeks after injection.

Revision septoplasty: review of sources of persistent nasal obstruction.

Background Patients with nasal obstruction from septal deviation commonly undergo septoplasty to improve nasal airflow. Some patients suffer from persistent obstruction after their primary septoplasty and may undergo a revision septoplasty to improve their nasal passageway. Our objective was to identify patients who underwent revision septoplasty and to identify their sources of persistent nasal obstruction. Methods Patients who underwent septoplasty at our institution between 1995 and 2005 were reviewed. Data is collected on demographics, comorbidities, age at septoplasty, associated and concomitant procedures, surgical approach, and anatomic site of obstruction. Results Five hundred forty-seven patients met inclusion criteria including 477 who underwent primary septoplasty and 70 who underwent revision surgery. Nineteen percent of nonrevision patients underwent nasal valve surgery along with their primary septoplasty versus 4% of patients in the revision group. Fifty-one percent of revision patients had nasal valve surgery at revision surgery. Patients who underwent sinus surgery along with primary septoplasty were less likely to undergo revision septoplasty. History of facial trauma, obstructive sleep apnea, site of deviation, and performance of inferior turbinate surgery did not affect the likelihood of revision septoplasty. Conclusion A significant number of patients who undergo revision septoplasty also have nasal valve collapse. We recommend that in addition to septal deviation and inferior turbinate hypertrophy, nasal valve function be fully evaluated before performing septoplasty. This will help to ensure a complete understanding of a patients nasal airway obstruction and, consequently, appropriate and effective surgical intervention.

Complications With Forehead Flaps in Nasal Reconstruction

To determine what characteristics and comorbidities are associated with a higher rate of complications in patients undergoing nasal reconstruction with a forehead flap.

Functional considerations in revision rhinoplasty.

The development of nasal obstruction after rhinoplasty is associated with significant patient dissatisfaction. Correction of nasal obstruction requires a thorough evaluation to determine the ANATOMIC EPICENTER of obstruction. The offending structure can usually be traced to abnormalities in the internal nasal valve, intervalve area, or the external nasal valve and may be static or dynamic. Surgical correction of the internal nasal valve using spreader grafts, flaring sutures, and butterfly grafts has been shown to increase the cross-sectional area of this nasal valve, improving nasal airflow and patient satisfaction. External valve dysfunction from cicatricial stenosis may be addressed with local flaps; however, larger stenoses may require composite grafts. Alar base malposition can be addressed by repositioning of the alar base with local island flaps. Intervalve dysfunction involves the important area between the external and internal valves, under the supra-alar crease, and is the most common site of obstruction. Its correction often involves alar batten grafts and reconstruction of the lateral crura. Inferior turbinate hypertrophy and concha bullosa may be addressed as adjunctive therapy to increase nasal airflow. This article on nasal obstruction after rhinoplasty emphasizes the precise anatomic diagnosis and describes successful methods used to correct the dysfunction.

Nasal reconstruction: the state of the art

Purpose of reviewCutaneous malignancies of the nose are common problems and create the need for nasal reconstruction within many otolaryngology practices. In spite of the fact that such reconstruction is an ancient art, there continue to be innovations and advances that allow for more predictable and functional long-term results. Recent findingsAnalyzing the nasal defect through an organized algorithm can be useful in many circumstances, especially when one needs to consider vectors of tension, minimizing alar base asymmetry, resultant scars, and preservation of the intranasal airway. Application of the principle of aesthetic subunits has greatly improved the cosmetic results for many large nasal defects, and there have been some proposals to modify the original definitions and concept. Structural reconstruction is paramount with complex defects that involve the nasal framework or with those that are located in functionally critical areas. Autogenous cartilage grafting remains the gold standard, but the use of alloplastic and homograft materials for grafting continues to be reported as an alternative. Internal lining repair is essential with larger defects and the versatility of intranasal flaps is understood, but at times not available. Other flaps have been described and may be useful on such occasions. SummaryThere are many considerations during nasal reconstruction, and the surgeon must be facile with a variety of options within his/her armamentarium.