Applications of hyperbaric oxygen in otolaryngology head and neck surgery: facial cutaneous flaps.

Hyperbaric oxygen therapy is of significant benefit in the setting of an ischemic flap of the head and neck. Mechanistically, hyperbaric oxygen decreases local tissue edema and improves oxygen delivery to compromised tissues. Both capillary and fibroblast in-growth occur at a greater rate with hyperbaric oxygen therapy, and there is an increase in the tensile strength of the wound. Additional indications in the head and neck include traumatic composite amputations, necrotizing soft-tissue infections, and osteoradionecrosis of the facial skeleton.

Adolescent gingival squamous cell carcinoma: Report of a case and review of the literature.

In this article we describe a case of adolescent squamous cell carcinoma of the gingiva. The tumor presented as an ulcerative lesion of the gingiva that was originally thought to be pseudoepitheliomatous hyperplasia. The pathologic differentiation between squamous cell carcinoma and pseudoepitheliomatous hyperplasia is discussed and a review of the literature with respect to pediatric and adolescent oral squamous cell carcinoma is presented. The reported case illustrates the difficulties that may be encountered in attempting to histopathologically distinguish between pseudoepitheliomatous hyperplasia and well-differentiated squamous cell carcinoma of the oral cavity.

Evaluation of clinically applicable exsanguination treatments to alleviate venous congestion in an animal skin flap model.

This study compares the effectiveness of alleviating venous congestion with mechanically-made outlets or leech therapy in promoting skin flap survival. Free flaps of abdominal skin (3 x 6 cm) were raised on Sprague-Dawley rats and subjected to ischemic events, simulating venous congestion. Animals received 1) no treatment; 2) two treatments involving two 18-gauge needle-puncture outlets; or 3) two sessions of leech therapy. Flap perfusion was monitored with a scanning laser Doppler flowmeter. Photographic images of flaps at 7 days were assessed for areas of normal tissue (n = 15), and laser Doppler flowmeter data consisted of control (n = 6), outlet (n = 6), and leech (n = 7). Both the needle-puncture outlet (40.0% +/- 9.24%) and leech treated (34.6% +/- 7.34%) groups had a significantly greater surviving skin area than untreated control flaps (8.0% +/- 5.0%), with 2 of 15 flaps receiving mechanical outlets exhibiting > 90% surviving area. After 7 days, laser Doppler flowmeter data showed greater mean perfusion in the outlet (71.7% +/- 16.8%) and leech (92.6% +/- 17.2%) treated groups, compared to controls (15.2% +/- 10.2%). There was a significant increase in perfusion in the outlet (13.3% +/- 6.2%) and leech (9.1% +/- 1.1%) treated groups from the end of secondary ischemia to day 7 (p < 0.05) compared to controls. The results suggest that two spatially separated outlets are as effective as one leech in increasing the area of surviving skin in venous congested flaps.

Wound complications of abdominoplasty in obese patients.

The records of 90 patients who underwent an abdominoplasty at the University of Virginia Health Sciences Center were analyzed to determine the effect of obesity on the incidence of complications after this surgery. The study patients were divided into three groups-obese, borderline, and nonobese-based on the degree to which their preoperative weights varied from their ideal body weight. A history of previous bariatric surgery was also analyzed to determine what impact that might have on subsequent abdominoplasty. Results showed that 80% of obese patients had complications compared with the borderline and nonobese patients, who had complication rates of 33% and 32.5% respectively (p = 0.001). Previous gastric bypass surgery had no significant effect on the incidence of postabdominoplasty complications. Based on these findings the authors conclude that obesity at the time of abdominoplasty has a profound influence on the wound complication rate following surgery, regardless of any previous weight reduction surgery.

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.

Correction of posterior sagittal craniosynostosis.

Craniosynostosis involving the posterior sagittal suture results in a characteristic skull deformity known as bathrocephaly. Surgical correction of this deformity using the reverse pi procedure has yielded inconsistent results. We present a new method for expanding the transverse posterior skull while simultaneously reducing the longitudinal dimension. An absorbable microplate-reinforced bone strut is used as a framework on which the remainder of the skull is reconfigured; its stability prevents relapse. The posterior skull squeeze is produced using absorbable mesh plates. Use of rigid fixation is limited to absorbable hardware in the growing craniofacial skeleton.

Sheets, 3-D strands, trimensional (3-D) shapes, and sutures of either reinforced or nonreinforced expanded polytetrafluoroethylene for facial soft-tissue suspension, augmentation, and reconstruction.

Expanded polytetrafluoroethylene (e-PTFE) is an expanded, fibrillated polymer recently used in facial reconstruction. This material is produced in two compositions: pure e-PTFE, for sheets, 3-D strands, and sutures; and e-PTFE reinforced with fluorinated ethylene propylene (FEP) for sheets and trimensional (3-D) shapes. This material has been used for facial soft-tissue suspension, augmentation, and reconstruction and has demonstrated advantages over autologous grafts due to its optimal tissue incorporation, low infection risk, and biological inertness.

High-density porous polyethylene for facial bone augmentation.

Medpor is a porous polyethylene biomaterial used in plastic and reconstructive surgery in the craniofacial skeleton. Its porous nature allows for substantial vascular and soft-tissue ingrowth. Medpor is available in a variety of implants including block, sheet, and preformed shapes. In vitro and in vivo studies have demonstrated that Medpor has been successfully used in the reconstruction of the orbital floor and external ear, and in augmentation of the chin, mandibular, nasal, and malar regions.

Technical considerations in the use of polymethylmethacrylate in cranioplasty.

Polymethylmethacrylate (PMMA) is a self-curing acrylic resin that can be used in the repair of cranial defects. It is available in three forms: PMMA without mesh, PMMA reinforced with mesh, and PMMA preformed to fit a defect. In cranioplasty, the size and location of the defects provide the selection criteria for the use of PMMA. PMMA without mesh is ideal for small defects (5 cm2-15 cm2). PMMA reinforced with mesh is used for moderate sized defects (16 cm2-49 cm2). For very large defects (> or = 50 cm2), a CT scan guided mold is recommended because it provides the ideal contour and shape that simulates the normal skull.

Polydimethylsiloxane for augmentation of the chin, malar, and nasal bones.

Polydimethylsiloxane (PDMS) is used for augmentation of the chin, malar and nasal bones and is available through three different manufacturers. PDMS has been widely accepted by surgeons for bone augmentation because of its variability in hardness, its ability to be easily molded and shaped, and its biological inertness. Wound repair around PDMS implants is achieved through capsule formation. Fibrous capsule formation can be interrupted by infection, immune reaction, implant migration, or extrusion. Recent studies have shown no correlation between silicone implants and connective tissue disease.

Anorganic bovine bone and analogs of bone mineral as implants for craniofacial surgery: a literature review.

Hydroxyapatite compounds and a new anorganic bovine bone mineral are materials that offer an alternative to autologous bone grafting. Ceramic hydroxyapatite implants are limited in their usefulness due to difficulty in contouring the cortical form and the tendency for the granular form to exist outside the reconstruction site. These limitations have been overcome by the advent of a hydroxyapatite cement paste exhibiting good biocompatibility, contour manipulation, implant stability and osseoinduction. Preliminary studies indicate that a new resorbable anorganic bovine bone mineral with a chemical composition and structure similar to human bone promotes initial bony healing more readily than its synthetic hydroxyapatite counterpart, and therefore may serve as an excellent alternative for craniofacial reconstruction.

Traumatic chronic TMJ dislocation: report of an unusual case and discussion of management.

Dislocation of the temporomandibular joint (TMJ) is most often spontaneous, but it can be associated with direct or indirect head and neck trauma. The disorder may be treated in general by simple closed techniques, if managed acutely. If the dislocation becomes chronic, however, open reduction is usually required. The article discusses various methods for an open surgical approach described in the literature. A case of a prolonged TMJ dislocation is presented, involving a severe bilateral mandibular dislocation with the condyles displaced into the infratemporal fossa and the lateral poles of the condyles articulating on the inner aspect of the zygomatic arch. An open approach, involving masseter, temporalis, and the medial pterygoid muscles, was utilized, followed by the use of scissors mouth props, Erich arch bars, and postoperative elastic traction.

Elevated levels of transforming growth factors beta 2 and beta 3 in lambdoid sutures from children with persistent plagiocephaly.

OBJECTIVE: To analyze the pertinent history and physical findings specific to the subset of patients with a progressive posterior skull deformity, requiring surgery to correct their deformity. PATIENTS: Since the Academy of Pediatrics issued its recommendation on supine positioning of infants to prevent sudden infant death syndrome (SIDS) in 1992, 73 children have presented to the University of Virginia Craniofacial Anomalies Clinic with posterior-skull deformities. The majority were successfully managed with conservative therapy, but in six patients, the deformity was severe and persistent, requiring surgical correction. All six children were older (7.5-12 mo), presenting with more severe morphologic appearances and a higher incidence of associated neurodevelopmental delay. Three had family backgrounds of isolated craniosynostosis. METHODS: Characteristics of these patients were examined to determine why they may have differed from those that responded to conservative management. Immunohistochemical staining of their lambdoid sutures was performed. RESULTS: Significantly increased staining for TGF-beta 2 and TGF-beta 3, potent stimulators of bone cell growth and differentiation, was seen in all 'affected' sutures from the flattened side of the skull, compared to unaffected sutures from the protruding side of the skull-a pattern similar to that seen during normal bony obliteration of calvarial sutures. CONCLUSION: The majority of patients with posterior plagiocephaly associated with positioning responded to conservative management, while a small subset of patients with persistent posterior skull deformation required surgical intervention. A genetic basis for the latter patients' persistent plagiocephaly, rather than positioning, cannot be ruled out. Genetics, prolonged external pressure against the sutures, or a combination of these factors may lead to permanently raised levels of growth factors in 'affected' sutures.

Experimental expansion of the maxillary sinus.

To assess the feasibility of "tissue" expansion as a means of midface advancement for correction of hypoplasia, expanders were placed in the left maxillary sinuses of New Zealand White rabbits. Twenty-one animals were used for the study, all of whom underwent implantation of radiopaque dental amalgam markers adjacent to cranial sutures at 9 days of age. The nonoperative control group (n = 13) underwent no further surgery. At 30 days of age, the experimental group (n = 8) underwent placement of an inflatable 1-mL Silastic tissue expander in the left maxillary sinus. After 1 week, inflation was begun in serial increments of 0.15-mL normal saline to a total volume of approximately 1.05 mL over a 2-week period. Lateral cephalometrograms were obtained at 9, 30, 60, and 90 days of age to measure growth of the craniofacial skeleton. Both groups demonstrated similar growth between 9 and 30 days of age; however, insertion and inflation of the tissue expander resulted in a statistically significant (p < 0.05) increase in posterior facial height, followed, in 30 days, by a significant increase in the length of the anterior cranial base. The remainder of the cranial base and the cranial vault grew without significant differences between the groups. This study demonstrates that changes in facial morphology can be effected in the growing skeleton through tissue expansion and provides further evidence to support the concept of an interrelated facial skeletal-basicranial-neurocranial axis.