Rates of bone reabsorption and union in mandibular reconstruction using the osteocutaneous radial forearm free flap

BACKGROUND

Historical concerns over bone resorption and malunion of the osteocutaneous radial forearm free flap (OCRFFF) limited its widespread adoption for head and neck reconstruction, despite lack of outcomes data evaluating this notion.

METHODS

A retrospective cohort study was performed including patients 18 years or older who underwent reconstruction of the mandible using an OCRFFF. Linear modeling and logistic regression were used to evaluate the change in bone volume and union over time.

RESULTS

One hundred and twenty-one patients were included in the study. A mixed effects linear model incorporating age, sex, treatment type, and number of bone segments did not demonstrate a significant loss of bone volume over time. A logistic regression model identified lack of adjuvant treatment and time to be significantly associated with complete union.

CONCLUSION

This study supports that the OCRFFF is a stable form of osseus reconstruction for defects of the head and neck.

Comparison of Modern Rigid Fixation Plating Outcomes for Segmental Mandibular Microvascular Reconstruction

OBJECTIVES/HYPOTHESIS

New advances in osseous microvascular mandibular rigid fixation are being employed at many institutions. These include standardized prebent/preformed reconstruction plates as well as computer-aided design/computer-aided manufacturing (CAD/CAM) custom plates that are patient specific. Our goal was to assess and compare the outcomes of both of these new technologies when utilized for mandibular microvascular reconstruction.

STUDY DESIGN

Retrospective chart review.

METHODS

Subjects were categorized into two groups according to their mandibular rigid fixation technique: group 1 = prebent/preformed plates and group 2 = CAD/CAM custom plates. Primary outcome measures were 1) perioperative complications (defined as deep tissue infection, wound dehiscence resulting in bone exposure, and/or plate exposure) and 2) reoperation rates for mandibular hardware failure/explantation. Statistical analysis consisted of χ² , Fisher exact test, and multivariable regression models.

RESULTS

A total of 142 subjects underwent microvascular mandibular reconstruction in a 6-year period. Eighty-nine subjects utilized prebent/preformed plates, and 53 employed CAD/CAM custom plates. Perioperative complications occurred in 32 of 89 (35.9%) subjects with prebent/preformed plates and 11 of 53 (20.7%) subjects using CAD/CAM custom plates. Reoperation requiring hardware explantation occurred in 18 of 89 (20.2%) subjects and three of 53 (5.6%) using CAD/CAM custom plates. Statistical comparison of perioperative complications between the two groups approached significance (P = .0556), and the rate of reoperation was significant favoring CAD/CAM implants (P = .0180).

CONCLUSIONS

In our experience, CAD/CAM custom plates utilized for rigid fixation during microvascular mandibular reconstruction demonstrated fewer complications and statistically lower reoperation rates when compared with prebent/preformed plates.

LEVEL OF EVIDENCE

2c Laryngoscope, 129:1081-1086, 2019.

Potent Antitumor Effects of a Combination of Three Nutraceutical Compounds

Head and neck squamous cell carcinoma (HNSCC) is associated with low survival, and the current aggressive therapies result in high morbidity. Nutraceuticals are dietary compounds with few side effects. However, limited antitumor efficacy has restricted their application for cancer therapy. Here, we examine combining nutraceuticals, establishing a combination therapy that is more potent than any singular component, and delineate the mechanism of action. Three formulations were tested: GZ17-S (combined plant extracts from Arum palaestinum, Peganum harmala and Curcuma longa); GZ17-05.00 (16 synthetic components of GZ17-S); and GZ17-6.02 (3 synthetic components of GZ17S; curcumin, harmine and isovanillin). We tested the formulations on HNSCC proliferation, migration, invasion, angiogenesis, macrophage viability and infiltration into the tumor and tumor apoptosis. GZ17-6.02, the most effective formulation, significantly reduced in vitro assessments of HNSCC progression. When combined with cisplatin, GZ17-6.02 enhanced anti-proliferative effects. Molecular signaling cascades inhibited by GZ17-6.02 include EGFR, ERK1/2, and AKT, and molecular docking analyses demonstrate GZ17-6.02 components bind at distinct binding sites. GZ17-6.02 significantly inhibited growth of HNSCC cell line, patient-derived xenografts, and murine syngeneic tumors in vivo (P < 0.001). We demonstrate GZ17-6.02 as a highly effective plant extract combination and pave the way for future clinical application in HNSCC.

Cancer-Associated Fibroblasts Drive Glycolysis in a Targetable Signaling Loop Implicated in Head and Neck Squamous Cell Carcinoma Progression

Despite aggressive therapies, head and neck squamous cell carcinoma (HNSCC) is associated with a less than 50% 5-year survival rate. Late-stage HNSCC frequently consists of up to 80% cancer-associated fibroblasts (CAF). We previously reported that CAF-secreted HGF facilitates HNSCC progression; however, very little is known about the role of CAFs in HNSCC metabolism. Here, we demonstrate that CAF-secreted HGF increases extracellular lactate levels in HNSCC via upregulation of glycolysis. CAF-secreted HGF induced basic FGF (bFGF) secretion from HNSCC. CAFs were more efficient than HNSCC in using lactate as a carbon source. HNSCC-secreted bFGF increased mitochondrial oxidative phosphorylation and HGF secretion from CAFs. Combined inhibition of c-Met and FGFR significantly inhibited CAF-induced HNSCC growth in vitro and in vivo (P < 0.001). Our cumulative findings underscore reciprocal signaling between CAF and HNSCC involving bFGF and HGF. This contributes to metabolic symbiosis and a targetable therapeutic axis involving c-Met and FGFR.Significance: HNSCC cancer cells and CAFs have a metabolic relationship where CAFs secrete HGF to induce a glycolytic switch in HNSCC cells and HNSCC cells secrete bFGF to promote lactate consumption by CAFs. Cancer Res; 78(14); 3769-82. ©2018 AACR.

Secretory Autophagy in Cancer-Associated Fibroblasts Promotes Head and Neck Cancer Progression and Offers a Novel Therapeutic Target

Despite therapeutic advancements, there has been little change in the survival of patients with head and neck squamous cell carcinoma (HNSCC). Recent results suggest that cancer-associated fibroblasts (CAF) drive progression of this disease. Here, we report that autophagy is upregulated in HNSCC-associated CAFs, where it is responsible for key pathogenic contributions in this disease. Autophagy is fundamentally involved in cell degradation, but there is emerging evidence that suggests it is also important for cellular secretion. Thus, we hypothesized that autophagy-dependent secretion of tumor-promoting factors by HNSCC-associated CAFs may explain their role in malignant development. In support of this hypothesis, we observed a reduction in CAF-facilitated HNSCC progression after blocking CAF autophagy. Studies of cell growth media conditioned after autophagy blockade revealed levels of secreted IL6, IL8, and other cytokines were modulated by autophagy. Notably, when HNSCC cells were cocultured with normal fibroblasts, they upregulated autophagy through IL6, IL8, and basic fibroblast growth factor. In a mouse xenograft model of HNSCC, pharmacologic inhibition of Vps34, a key mediator of autophagy, enhanced the antitumor efficacy of cisplatin. Our results establish an oncogenic function for secretory autophagy in HNSCC stromal cells that promotes malignant progression. Cancer Res; 77(23); 6679-91. ©2017 AACR.

Use of the 2.0-mm Locking Reconstruction Plate in Primary Oromandibular Reconstruction after Composite Resection

OBJECTIVE: To review our experience with 2.0-mm locking reconstruction plate (LRP) system for patients requiring oromandibular reconstruction.

STUDY DESIGN: Retrospective case review of 43 consecutive patients who underwent mandibular composite resection with immediate reconstruction.

SETTING: Tertiary care center.

RESULTS: Forty-three patients underwent oromandibular reconstruction with the 2.0-mm mandibular LRP system and free flaps containing vascularized bone. Mean follow-up was 11 months. There were no intraoperative difficulties utilizing this system. Two (5%) patients had partial fasciocutaneous flap loss resulting in plate exposure. There were no instances of plate fracture or complications requiring plate removal to date.

CONCLUSION: 2.0-mm LRP mandibular system is reliable even in the setting of previous or adjuvant radiation therapy. Its technical ease of application, contouring malleability, and very low profile have proven to be advantageous in oromandibular reconstruction.

SIGNIFICANCE: No previous descriptions of use of the 2.0-mm LRP in combination with osteocutaneous free flaps for mandibular reconstruction are found in the literature. EBM rating: C.

Superior omohyoid muscle flap repair of cervical esophageal perforation induced by spinal hardware

Cervical esophageal perforation is a rare and life-threatening condition. Its prompt diagnosis and treatment require a high index of suspicion. Cervical spine hardware is an uncommon cause of posterior esophageal perforation. Management has included a variety of musculofascial flaps for surgical repair. We present 2 cases of cervical esophageal perforation induced by spinal hardware that were repaired with a superior omohyoid muscle (SOM) flap for closure and/or primary closure reinforcement. Advantages and techniques of the SOM flap are discussed.

The Role of the Head and Neck Surgeon in the New World of Health Care Reform

The landscape of health care delivery in the United States is in the midst of irreversible and progressive changes that present tremendous opportunities to do maximal good for patients. Clinicians must embrace this opportunity to ensure this redesign is done properly and to the benefit of patients-not the bottom line of the health system. This sweeping change in health care will also align the benefits of preventive care and public health with the economic health of health systems for the first time. Clinicians will be incentivized to ensure that legislative environment fully supports efforts to create a healthier population-which for the American Head and Neck Society means a reduction or elimination of tobacco use and widespread HPV vaccination of children.

A longitudinal study of emotional intelligence training for otolaryngology residents and faculty

IMPORTANCE

Emotions underlie and influence physician communications and relationships with patients and colleagues. Training programs to enhance emotional attunement, or emotional intelligence (EI), for physicians and assess training effects are scarce.

OBJECTIVE

To assess whether an EI training program for otolaryngology residents and faculty affects patient satisfaction.

DESIGN, SETTING, AND PARTICIPANTS

Prospective longitudinal, cohort study of physician residents and faculty in an EI training program at the Department of Otolaryngology, University of Kansas Medical Center, with annual training from 2005 to 2011.

INTERVENTIONS

Three levels of interventions included 4 years of repeated EI assessment, 7 years of highly interactive EI training with high-risk/high-stress simulations, and ongoing modeling and mentoring of EI skills by faculty.

MAIN OUTCOMES AND MEASURES

Four levels of outcome of the EI training were assessed with the following questions: Did participants enjoy the program? Could they apply the training to their practice? Did it change their behavior? Did it affect patient satisfaction? The Emotional Quotient Inventory (EQ-i) was administered to faculty and residents, and the Press Ganey Patient Satisfaction Survey was completed by patients.

RESULTS

Ninety-seven percent of participants (103 of 106) reported that they enjoyed the programs, and 98% (104 of 106) reported that they have or could have applied what they learned. Participants demonstrated improvement in mean EQ-i scores from 102.19 (baseline/pretraining) to 107.29 (posttraining and assessment 1 year later; change, 6.71; 95% CI, 3.44-9.98). This increase was sustained in successive years, and these results were supported with linear growth curve analysis. The total department mean EQ-i score in pretraining year 2005 was 104.29 ("average" range), with posttraining scores in the "high average" range (112.46 in 2006, 111.67 in 2007, and 113.15 in 2008). An increase in EQ-i scores and EI training corresponded with an increase in patient satisfaction scores. Percentile rank patient satisfaction scores before EI training ranged from 85% to 90%; after training, scores ranged from 92% to 99%.

CONCLUSIONS AND RELEVANCE

Emotional intelligence training positively influences patient satisfaction and may enhance medical education and health care outcome.

Parotidectomy Defect: To Reconstruct or Not

Program Description:

Parotidectomy is a common head and neck surgical procedure. While management options of facial nerve injury are well understood, the issues related to soft tissue deficit are underappreciated and frequently untreated. This miniseminar will characterize various parotidectomy soft tissue defects and describe the impact on facial cosmesis, Frey’s syndrome, and preparation of the wound for adjuvant therapy. A case based presentation will discuss the use of allografts, avascular autografts, and pedicled and free flaps to correct external surface and contour/volume defects. Frey’s syndrome and its prophylactic and symptomatic management will be discussed.

Educational Objectives:

1) Recognize cosmetic and functional deficits associated with parotid surgery. 2) Formulate reconstructive options for correction of surface and volume defects. 3) Evaluate pathophysiology and management of Frey’s Syndrome.

Factors influencing morbidity after surgical management of malignant thyroid disease

OBJECTIVES

We performed a retrospective study of cases from 2005 to 2010 at an academic tertiary care center to analyze the factors that influence morbidity in surgical management of thyroid malignancy.

METHODS

The rates of recurrent laryngeal nerve (RLN) injury and hypoparathyroidism (HPT) were analyzed in the entire cohort. The comparison groups were 1) primary surgery versus revision; 2) total thyroidectomy versus total thyroidectomy combined with neck node dissection; and 3) two groups defined by surgical technique according to the RLN approach: group 1, in which the RLN was identified inferiorly in the tracheoesophageal groove, and group 2, in which the RLN was identified near the cricothyroid joint point of entry.

RESULTS

We reviewed 308 patients who underwent surgery for thyroid cancer. Thirty-six (11.7%) had temporary HPT, and 8 (2.6%) had permanent HPT. Of a total of 586 RLNs at risk, 16 (2.7%) had temporary damage and 2 (0.3%) had permanent damage. The incidences of temporary RLN injury significantly differed between the primary-surgery and revision-surgery groups (2.5% versus 15.6%; p = 0.001), and also between the groups with total thyroidectomy and thyroidectomy with neck dissection (1.2% versus 7.8%; p = 0.027). The incidences of temporary HPT were significantly different between the groups with primary surgery and revision surgery (6.6% versus 31.3%; p = 0.001), between the groups with total thyroidectomy and total thyroidectomy with neck dissection (4.7% versus 15.6%; p = 0.009), and between group 1 and group 2 (surgical technique in terms of RLN approach; 8.2% versus 17.9%; p = 0.011). Permanent HPT and permanent RLN injury both occurred rarely in this cohort, with no significant differences among comparison groups.

CONCLUSIONS

Our study shows a higher incidence of temporary RLN injury and teniporary HPT in revision surgery cases and in total thyroidectomy with neck dissection. Temporary HPT was significantly more common when the RLN was identified near the cricothyroid joint.

Ultrasound for localization in primary hyperparathyroidism

OBJECTIVE

To evaluate the capability of ultrasound for preoperative localization in primary hyperparathyroidism.

STUDY DESIGN

Prospective study.

SETTING

Multi-institutional Midwest Head and Neck Cancer Consortium.

SUBJECTS AND METHODS

Two hundred twenty patients who underwent preoperative localization and had parathyroid surgery were evaluated. The findings of preoperative localization studies were correlated with surgical findings.

RESULTS

Preoperative ultrasonography, sestamibi scintigraphy, or both were obtained in 77%, 93%, and 69% of the patients, respectively. Preoperative ultrasonography and sestamibi scintigraphy localized an abnormality in 71% and 79% of patients, respectively. At the time of surgery, the localization by ultrasound was accurate in 82%. The accuracy of localization was similar for sestamibi scintigraphy (85%). In patients with inaccurate ultrasound localization, the sestamibi scintigraphy correctly identified the site of disease in only 45%. In patients with a nonlocalizing ultrasound, sestamibi scintigraphy was able to localize disease in only 47%, with 2 being in the mediastinum.

CONCLUSIONS

Ultrasonography is an acceptable initial localization study for patients with primary hyperparathyroidism. In patients with nonlocalizing ultrasound, sestamibi scintigraphy should be obtained, but can be expected to detect an abnormality in less than 50% of patients.

Outcomes of the osteocutaneous radial forearm free flap for mandibular reconstruction

IMPORTANCE

Limited donor and recipient site complications support the osteocutaneous radial forearm free flap (OCRFFF) for mandibular reconstruction as a useful option for single-stage mandibular reconstruction.

OBJECTIVE

To examine and report long-term outcomes and complications at the donor and recipient sites for patients undergoing the OCRFFF for mandibular reconstruction.

DESIGN

Retrospective review.

SETTING

Academic, tertiary care medical center.

PATIENTS

The study population comprised 167 consecutive patients who underwent single-staged mandibular reconstruction with an OCRFFF.

MEAN OUTCOME MEASURES

Rates of complications at the donor and recipient sites.

RESULTS

The mean patient age was 61 years (range, 20-93 years). Men compromised 68% of the population. Follow-up interval ranged from 2 to 99 months (mean, 25.9 months). The median length of bone harvested was 7 cm (range, 2.5-12.0 cm). Prophylactic plating was completed for each of the radii at the time of harvest. Donor site complications included radial fracture (1 patient [0.5%]), tendon exposure (47 patients [28%]), and donor hand weakness or numbness (13 patients [9%]). Recipient site complications included mandible hardware exposure (29 patients [17%]), mandible nonunion or malunion (4 patients [2%]), and mandible bone or hardware fracture (4 patients [2%]). Using regression analysis, we found that patients were 1.3 times more likely to have plate exposure for every increase of 1 cm of bone harvest length; this was statistically significant (P = .04).

CONCLUSIONS AND RELEVANCE

This is the largest single study reporting outcomes and complications for patients undergoing OCRFFF for mandibular reconstruction. Prophylactic plating of the donor radius has nearly eliminated the risk of pathologic radial bone fractures. Limited long-term donor and recipient site complications support the use of this flap for single-stage mandibular reconstruction.

Identifying incident oral and pharyngeal cancer cases using Medicare claims

Background

Baseline and trend data for oral and pharyngeal cancer incidence is limited. A new algorithm was derived using the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database to create an algorithm to identify incident cases of oral and pharyngeal cancer using Medicare claims.

Methods

Using a split-sample approach, Medicare claims’ procedure and diagnosis codes were used to generate a new algorithm to identify oral and pharyngeal cancer cases and validate its operating characteristics.

Results

The algorithm had high sensitivity (95%) and specificity (97%), which varied little by age group, sex, and race and ethnicity.

Conclusion

Examples of the utility of this algorithm and its operating characteristics include using it to derive baseline and trend estimates of oral and pharyngeal cancer incidence. Such measures could be used to provide incidence estimates where they are lacking or to serve as comparator estimates for tumor registries.

Ultrasound for Localization in Primary Hyperparathyroidism

Objective: Minimally invasive surgery for primary hyperparathyroidism has gained significant popularity. Preoperative localization is required, with ultrasonography and sestamibi imaging being most commonly utilized. When both are obtained, frequently the same site is localized. It is unclear that 2 localization techniques are required in patients with hyperparathyroidism.

Method: Prospectively collected data from the Midwest Head and Neck Cancer Consortium’s parathyroid protocol was retrospectively reviewed. The study included patients that had preoperative localization and subsequently underwent surgery. The localization studies were correlated to surgical findings.

Results: Of the 96 patients, preoperative US, sestamibi, or both studies were obtained in 77, 88, and 71, respectively. Preoperative US and sestamibi localized an abnormality in 69% and 80%, respectively. In patients with localizing US, surgical findings were exactly as predicted in 75% and localized to the correct side in 84%. The accuracy of localization was similar for sestamibi imaging. In 8 patients with inaccurate US localization, the sestamibi detected an abnormal gland in only 50%. In patients with a nonlocalizing US, sestamibi was able to detect disease in 75%, with 2 being in the mediastinum.

Conclusion: Given the lower cost of ultrasonography, it is an acceptable initial localization study for patients with primary hyperparathyroidism. In patients with nonlocalizing ultrasound, sestamibi imaging should be obtained. Frequently potential sites of disease will be identified, still allowing for a minimally invasive surgical approach.

Use of a structured template to facilitate practice-based learning and improvement projects

BACKGROUND

The Accreditation Council for Graduate Medical Education (ACGME) requires residency programs to meet and demonstrate outcomes across 6 competencies. Measuring residents' competency in practice-based learning and improvement (PBLI) is particularly challenging.

PURPOSE

We developed an educational tool to meet ACGME requirements for PBLI. The PBLI template helped programs document quality improvement (QI) projects and supported increased scholarly activity surrounding PBLI learning.

METHODS

We reviewed program requirements for 43 residency and fellowship programs and identified specific PBLI requirements for QI activities. We also examined ACGME Program Information Form responses on PBLI core competency questions surrounding QI projects for program sites visited in 2008-2009. Data were integrated by a multidisciplinary committee to develop a peer-protected PBLI template guiding programs through process, documentation, and evaluation of QI projects. All steps were reviewed and approved through our GME Committee structure.

RESULTS

An electronic template, companion checklist, and evaluation form were developed using identified project characteristics to guide programs through the PBLI process and facilitate documentation and evaluation of the process. During a 24 month period, 27 programs have completed PBLI projects, and 15 have reviewed the template with their education committees, but have not initiated projects using the template.

DISCUSSION

The development of the tool generated program leaders' support because the tool enhanced the ability to meet program-specific objectives. The peer-protected status of this document for confidentiality and from discovery has been beneficial for program usage. The document aggregates data on PBLI and QI initiatives, offers opportunities to increase scholarship in QI, and meets the ACGME goal of linking measures to outcomes important to meeting accreditation requirements at the program and institutional level.

HPV-Associated Oropharyngeal Cancer Tumor Board

Program Description: The incidence of Human Papilloma Virus (HPV)–related oropharyngeal cancer is increasing at a near-epidemic proportion. As such, otolaryngologists are diagnosing and treating greater numbers of patients, especially younger patients, with this distinct disease. There have been significant strides in our knowledge about the pathophysiology of this disease. Yet despite our increased knowledge, there are still several unanswered questions about the ideal management. The educational objective of this miniseminar is to provide otolaryngologists with up-to-date clinically relevant information about making treatment decisions for patients with oropharyngeal cancer. This will be done using a case-based format in the style of a multidisciplinary tumor board with incorporating audience participation. The cases discussed will incorporate basic concepts and controversial topics within the discussion. These topics will include 1) initial management with surgical techniques versus non-surgical modalities, 2) incorporating biomarkers (HPV, p16, others) and patient-related factors into initial treatment decision making, 3) optimal management of the neck, 4) management of patients with persistent/recurrent primary site disease after completion of initial therapy, and 5) management of patients with an unknown primary site when the neck metastasis is HPV positive. Panel members will provide support for their responses based on the best evidence-based medicine available. Standard available therapies, currently available and upcoming clinical trials, and future research directions will be emphasized. At the conclusion of this miniseminar, the participant will be able to describe the current “state-of-the-art” for evaluation and management of oropharynx cancer and discuss the underlying principles for how treatment decisions are made.

Educational Objectives: 1) Describe the current “state-of-the-art” for evaluation and management of HPV-associated oropharynx cancer. 2) Discuss the underlying principles for making treatment decisions for patients with oropharynx cancer. 3) Describe current standard treatment options, available clinical trials, and future research directions.

Osteocutaneous radial forearm free flap: long-term radiographic evaluation of donor site morbidity after prophylactic plating of radius

The osteocutaneous radial forearm free flap (ORFFF) is an ideal source of vascularized bone and soft tissue for repair of defects in reconstructions of the head and neck. However, studies have revealed significant donor site morbidity, decreasing the popularity of this procedure. We have previously reported our technique of prophylactic internal fixation of the radius at the time of graft harvest, developed to decrease donor radius fractures. This is a retrospective radiographic review of our long-term radius donor site morbidity. Forearm radiographs more than 3 years after ORFFF with prophylactic plating were evaluated and compared with prior postoperative films. No donor radius fractures were identified. All radiographs exhibited remodeling and/or reconstitution of donor radii. There was no evidence of implant failure, loosening, or surrounding osteopenia. This study lends further credibility to the ORFFF, when prophylactically plated, as a safe and reliable source of vascularized bone and soft tissue for reconstructive procedures.

Evaluating the Completeness of the SEER-Medicare Linked Database for Oral and Pharyngeal Cancer

Oral and pharyngeal cancer is a persistent oral health problem. Baseline and trend data to measure progress are lacking. Our long-term goal is to create an algorithm using Medicare claims to identify oral and pharyngeal cancer cases among those ages 65 and older. The goal of this project was to assess the completeness of the SEER-Medicare linked database for identifying incident oral and pharyngeal cancer cases. We compared incidence rates from the "gold-standard" SEER limited-use database to those from the SEER-Medicare linked database using a quasi-likelihood extension of Poisson regression, allowing for over-dispersion. Adjustment for age, sex, race and ethnicity, and interaction terms between these explanatory variables with data source were used to assess the completeness of the SEER-Medicare linked database among these subgroups. Approximately 6.4% of the cases were missing from the SEER-Medicare linked database. The completeness varied by race and ethnicity (p=0.066). Future development of an algorithm to identify oral and pharyngeal cancer cases using Medicare claims alone can potentially identify over 93% of the cases; however, Hispanic, non-Hispanic black, and non-Hispanic other race and ethnicity subgroups will be less likely than non-Hispanic whites to be identified in such future algorithms.

Immediate Gore-Tex sling suspension for management of facial paralysis in head and neck extirpative surgery

OBJECTIVE

We sought to evaluate the functional and aesthetic outcomes of immediate facial reconstruction with a Gore-Tex (expanded polytetrofluoroethylene) sling in irradiated patients undergoing large head and neck tumor extirpation with facial nerve resection.

STUDY DESIGN AND SETTING

We conducted a retrospective study of 17 patients at two academic institutions who underwent extirpative surgery with immediate Gore-Tex sling reconstruction and completed radiotherapy. Functional and aesthetic results were evaluated at three intervals.

RESULTS

All patients had excellent immediate results and good or excellent intermediate-term results. At long-term follow-up, results were good to excellent in 47% and unacceptable in 35% of patients.

CONCLUSION

In irradiated patients undergoing total parotidectomy with immediate facial reconstruction using Gore-Tex slings, early results are excellent, but there is a high incidence of major wound complications and unacceptable results in long-term follow-up.

SIGNIFICANCE

There is a high rate of late complications associated with immediate facial reconstruction with Gore-Tex slings in irradiated patients.

Role of cochlear integrity in cochlear nucleus glucose metabolism and neuron number after cochlea removal in aging broiler chickens

In the chicken auditory system, cochlear nucleus (nucleus magnocellularis, NM) neurons receive their only excitatory input from the ipsilateral cochlea. Cochlea removal (CR) results in an immediate decrease in NM neuron electrical activity, followed by death of approximately 30% of NM neurons. Previous work showed a decrease in NM activity and subsequent loss of NM neurons in all chicks. Egg layer adults showed NM neuron loss after CR, while neuron number remained stable in broiler adults. This suggested that effects of CR on NM were age- and breed-dependent. We now know that most aging egg layer chickens maintain largely normal cochleae throughout adulthood. Some exhibit cochlear damage with age. The converse is true of broiler chickens. Most aging broiler chickens display cochlear degeneration, with some maintaining normal cochlear anatomy throughout adulthood. The presence of extensive cochlear damage may alter the effect of CR on NM, leading to the described differences. Here, we examine the effect of unilateral CR on NM glucose metabolism and neuron number in 2, 30, 39, and 52 week-old broiler chickens found to have normal cochleae. Chickens with damaged cochleae were excluded. Using 2-deoxyglucose uptake to evaluate bilateral NM glucose metabolism, we found significantly decreased uptake ipsilateral to CR at each age examined. Bilateral cell counts revealed significant neuron loss ipsilateral to CR at each age examined. This suggests that NM glucose metabolism decreases and subsequent neuron death occurs in aging broiler chickens when a normal cochlea is removed. The status of the cochlea must play a role in the effect of deafferentation on NM glucose metabolism and neuron survival. The effect of CR appears to be dependent upon neither age nor breed, but upon cochlear integrity instead.

The role of the osteocutaneous radial forearm free flap in the treatment of mandibular osteoradionecrosis

OBJECTIVE

To evaluate the role of the osteocutaneous radial forearm free flap (OCRFFF) in the treatment of mandibular osteoradionecrosis (ORN).

STUDY DESIGN AND SETTING

Retrospective case review of patients who underwent OCRFFF oromandibular reconstruction after resection of nonviable tissue at an academic tertiary care center because of ORN. Patients with reconstructions other than OCRFFF were excluded from this study.

RESULTS

Nine patients underwent a composite oromandibular resection for ORN with a reconstruction using an OCRFFF between April 1998 and February 2003. All patients had failed previous less aggressive surgical and medical management of the ORN. Mean follow-up was 36 months (range, 14-67 months). There were no flap failures or significant immediate postoperative or long-term complications observed. All patients had successful restoration of mandibular integrity and continuity, with 100% success rate of stabilization of ORN. All patients were able to tolerate PO diet, with only one third having to supplement their diet with gastrostomy feedings, compared with 89% gastrostomy dependence preoperatively.

CONCLUSIONS

Primary or adjuvant radiotherapy for head and neck malignancies can result in ORN of the mandible. This difficult problem often requires surgical intervention. In our experience, the OCRFFF can be successfully used for oromandibular reconstruction, even in the setting of the heavily radiated tissue with excellent postoperative outcomes.

SIGNIFICANCE

This is the first study that demonstrates the efficacy of the OCRFFF as a treatment of mandibular ORN.

Comparison of Radial Forearm With Fibula and Scapula Osteocutaneous Free Flaps for Oromandibular Reconstruction

OBJECTIVE

To compare our experience with the osteocutaneous radial forearm free flap (group 1) (n = 108) with other commonly used osteocutaneous free flaps (group 2) (n = 56) such as the fibula and scapula in single-stage oromandibular reconstruction.

DESIGN

Retrospective case review.

SETTING

Tertiary-care academic medical center.

PATIENTS

One hundred sixty-three consecutive patients who underwent 164 mandibular reconstructions with osteocutaneous free flaps.

MAIN OUTCOME MEASURES

Assessment of preoperative and intraoperative variables for both groups. We compared recipient-site complication rate, intensive care unit stay, total hospital stay, and postoperative function.

RESULTS

The most common donor site used was the radius (n = 108 [66%]), followed by the fibula (n = 36 [22%]) and scapula (n = 20 [12%]). Mean follow-up was 29 months (range, 1-116 months). Group 2 patients had larger soft tissue and/or bony defects. Surgical and medical complication rates and major donor site morbidity in group 1 were similar or better when compared with those in group 2. The lengths of the intensive care unit (4 vs 7 days; P = .009) and hospital stays (13 vs 15 days; P = .06) were shorter in group 1. Although the microvascular success rate was similar in both groups, the local wound complication rate was significantly better for group 1. The difference for the length of intensive care unit stay was statistically significant and potentially amounts to more than 6000 dollars of savings. Functional outcomes, including the ability to tolerate oral diet, tracheostomy presence, and dental rehabilitation, were similar between the groups.

CONCLUSIONS

The primary site long-term morbidity, donor site morbidity, and postoperative function of osteocutaneous radial forearm free flaps are comparable to those of other commonly used osteocutaneous free flaps such as the fibula and scapula when used in single-stage oromandibular reconstruction.

Breed-dependent susceptibility to acute sound exposure in young chickens

Commercially available chickens fall into two categories: egg layers and broilers. Durham et al. (Hear. Res. 166 (2002) 82-95) showed that despite similar noisy living environments, cochleae of most adult broilers show extensive damage, while cochleae of adult egg layers are largely normal. This finding suggests that egg layers and broilers differ in their susceptibility to noise damage. Here, we evaluate breed differences in susceptibility to acoustic trauma. Young egg layers and broilers (10-17 weeks) were exposed to a 1500Hz pure tone (120dB SPL; 24h) and killed 24 or 72h later. Cochleae were prepared for scanning electron microscopy and photomicrographs of the cochlear surface were used to determine location and severity of damage. Cochleae were grouped based upon damage severity (moderate or severe). While location and area of damage were similar between both breeds at each recovery time, cochlear damage at 72h was more extensive than at 24h. We found no quantitative breed differences within either damage category or recovery time. However, more egg layers (25/27) than broilers (16/32) displayed severely damaged cochleae. Our findings conflict with those reported by Durham et al. (2002). Our results identify a breed-dependent difference in susceptibility to acute sound exposure, with young egg layers displaying increased sensitivity.

Predicting severity of cochlear hair cell damage in adult chickens using DPOAE input-output functions

Distortion product otoacoustic emissions (DPOAE) were recorded from the ear canal of aged broiler chickens which have been shown to present with age-related cochlear degeneration [Hear. Res. 166 (2002) 82]. We describe the relationship between the shape of the DPOAE input-output (I/O) function and the type of hair cell damage present at and between the cochlear frequency places of the DPOAE primary tones (f1 and f2). The mid stimulus level compressive growth of the mean DPOAE I/O functions is reduced in a graded fashion relative to the severity of hair cell damage. However, individual DPOAE I/O functions within most hair cell damage groups show large variability from this characteristic. Various least squares regression models were used to predict hair cell density from indices derived from the DPOAE I/O function (area, threshold and slope). The results showed that no simple linear relationship exists between hair cell density and the DPOAE I/O function indices. Multivariate binary logistic regression used DPOAE I/O function indices to predict membership in hair cell damage groups. The logistic model revealed that DPOAE threshold can be used to predict the occurrence of severe/total hair cell damage with good specificity though poor sensitivity.

Radiation-induced malignancy of the head and neck

OBJECTIVE

Our goal was to evaluate our experience with radiation-induced malignancy (RIM), compare that experience to the literature, and review treatment modalities.

STUDY DESIGN AND SETTING

The setting is the University of Kansas Medical Center. A retrospective review was performed to identify patients with RIM. Patients were included if they met the criteria for RIM as delineated in the literature.

RESULTS

Thirteen patients met the criteria for RIM. The mean latency period was 22 years. Sarcomas were the most common type of RIM and the paranasal sinuses were the most common location. Surgical resection was our treatment of choice.

CONCLUSIONS

Our patient series differs from previous reports in that sarcomas were the predominating RIM and the paranasal sinuses were the most common location. We noted a shorter latency period than has been previously published. Surgical excision is the treatment of choice.

EBM RATING

C.

Gentamicin pharmacokinetics in the chicken inner ear

Avians have the unique ability to regenerate cochlear hair cells that are lost due to ototoxins or excessive noise. Many methodological techniques are available to damage the hair cells for subsequent scientific study. A recent method utilizes topical application of an ototoxic drug to the round window membrane. The current study examines the pharmacokinetics of gentamicin in the inner ear of chickens following topical application to the round window membrane or a single systemic high dose given intraperitoneally. Chickens were given gentamicin topically or systemically and survived for 1, 4, 12, 24, or 120 h (controls at 4 and 120 h). Serum and perilymph samples were obtained prior to sacrifice and measured for gentamicin levels. Results revealed higher levels of gentamicin in the perilymph of topically treated chickens than systemically treated chickens, with significant amounts of gentamicin still present in both at the latest survival time of 5 days. As expected, systemically treated chickens had much higher levels of gentamicin in the serum than topically treated chickens. Advantages and disadvantages to each method of drug administration are discussed.

Effects of age and cochlear damage on the metabolic activity of the avian cochlear nucleus

Most aging commercially raised broiler chickens display a progressive loss of cochlear hair cells in a pattern similar to the cochlear degeneration found in aging humans: basal (high frequency) hair cells are affected first, followed by apical (low frequency) hair cells [Durham et al., Hear. Res. 166 (2002) 82-95]. Here, cochlear anatomy was assessed from scanning electron micrographs. Then, the metabolic activity of cochlear nucleus (nucleus magnocellularis, NM) neurons in 15-19, 30, 39, 40, and 65-66 week old broiler chickens was examined using cytochrome oxidase histochemistry and compared to the degree of cochlear abnormality. Cochleae of 15-19 week old birds are largely normal; therefore the level of NM metabolic activity is considered the baseline. Cochleae of the 30 week old group display mild damage and hair cell regeneration in the base. Metabolic activity in rostral (high frequency) NM is increased relative to the baseline, while activity remains unchanged in caudal (low frequency) NM. The 39 and 65-66 week old groups display severe and total damage extending into the apex of the cochlea. Metabolic activity is decreased in rostral and caudal NM at these ages. These results suggest that auditory central nervous system metabolism (cytochrome oxidase activity) is affected by changes in the aging chicken cochlea.

Avian brainstem neurogenesis is stimulated during cochlear hair cell regeneration

Unlike mammals, adult avians are able to regenerate cochlear sensory hair cells following injury. Brainstem auditory neurons in chicken nucleus magnocellularis (NM), which receive their sole excitatory afferent input from the cochlea, were examined for evidence of mitosis during ototoxin-induced loss and regeneration of cochlear hair cells. Using tritiated thymidine as a mitotic marker in tissue processed for autoradiography and counterstained with thionin, labeled NM neurons and glia were counted from chickens killed 16 days after gentamicin or saline injections. Newly generated NM neurons were observed during cochlear hair cell regeneration. More labeled neurons were observed in the experimental chickens, but a few were also seen in the control chickens. We predicted labeled NM neurons would be found solely in the rostral high frequency region, given the gentamicin-induced high frequency cochlear hair cell loss and regeneration. However, the labeled NM neurons were located throughout the tonotopic axis of the nucleus. The total number of labeled neurons was lower than predicted. Many labeled NM glia were observed in experimental and control chickens. Labeled cells were also observed throughout the chicken brainstem and cerebellum in both experimental and control chickens, indicating great potential for CNS plasticity. Results in NM indicate the avian auditory system is capable of regenerating brainstem auditory neurons in addition to the previously well-established capability of regenerating cochlear hair cells in response to ototoxic injury. Recovery of both central and peripheral auditory components will be necessary to restore hearing damaged by noise or ototoxic drugs.

Time course and quantification of changes in cochlear integrity observed in commercially raised broiler chickens

Extensive cochlear hair cell damage and loss occurs in aged broiler chickens. We describe the time course and several characteristics of this decline in cochlear integrity in 19-, 30-, 38- and 66-week-old commercially raised broiler chickens. The 19-week-old group is normal and serves as a baseline for comparison. Generally, cochlear damage increases in severity and percent length of the cochlea with age. Hair cell density increases from the base to the apex. Density is similar across the groups in regions of the cochlea that sustained little or no damage, and decreases in regions of extreme damage. Counts of normal and abnormal hair cells are inversely related. A subset of 66-week-old birds has higher density measurements and increased hair cell counts in the apical region of the cochlea. The progressive damage found in these commercially raised birds is described in the context of both the effects of age and noise exposure on the auditory system. Two additional groups of birds were raised at the University of Kansas Medical Center in a quieter environment to determine the cause of the damage seen in age-matched commercially raised birds. These cochleae are largely normal; a small number displayed damage. This suggests that noise exposure exacerbates naturally occurring cochlear degradation.

Percutaneous ethanol sclerotherapy of venous malformations of the tongue

BACKGROUND AND PURPOSE

Percutaneous ethanol sclerotherapy has been reported to be efficacious for head and neck venous malformations. We sought to evaluate the safety and efficacy of percutaneous sclerotherapy by using ethanol for treatment of symptomatic venous malformations of the tongue.

METHODS

Eleven sclerotherapy procedures were performed in seven patients from January 1995 to February 2001. Patient age ranged from 19 months to 57 years (mean age, 32 years). Four patients were male and three were female. Mean follow-up was 36 months. The volume of ethanol used per treatment session ranged from 2 to 32 cc (mean, 16 cc).

RESULTS

Sclerotherapy provided significant improvement or resolution of symptoms for all patients. There were no major complications. One patient had a small (3 x 2 cm) area of skin blistering at the injection site. All patients experienced pain and swelling to a variable degree. Sclerotherapy resulted in resolution of symptoms in six of seven patients. Three patients had resolution of symptoms after one procedure. Four patients each underwent two sclerotherapy procedures. One patient who remained symptomatic but improved after undergoing two procedures underwent an anterior glossectomy and is now asymptomatic.

CONCLUSION

Percutaneous ethanol sclerotherapy is a safe and effective method of treating symptomatic venous malformations of the tongue.

Breed differences in cochlear integrity in adult, commercially raised chickens

Two types of chickens are commercially available. Broiler birds are bred to develop quickly for meat production, while egg layers are bred to attain a smaller adult size. Because we have observed breed differences in the response of central auditory neurons to cochlear ablation in adult birds [Edmonds et al. (1999) Hear. Res. 127, 62-76], we examined cochleae from the two breeds for differences in integrity. We evaluated cochlear hair cell structure using scanning electron microscopy and cochlear hair cell function using distortion product otoacoustic emissions (DPOAEs) and the auditory brainstem response. We observed striking breed differences in cochlear integrity in adult but not hatchling birds. In adult broiler birds, all cochleae showed damage, encompassing at least the basal 29% of the cochlea. In 15 of 18 broiler ears, damage was observed throughout the basal 60% of the cochlea. In contrast, cochleae from egg layer adults were largely normal. Two thirds of egg layer ears showed no anatomical abnormalities, while in the remainder cochlear damage was seen within the basal 48% of the cochlea. DPOAEs recorded from egg layer birds showed loss of high frequency emissions in every ear for which the cochlea displayed anatomical damage. Average sound pressure levels in both commercial facilities were 90 dB, suggesting these two breeds may exhibit differential susceptibility to noise damage.

Resolution of acquired pulmonary arteriovenous malformations in a patient with total anomalous systemic venous return

An 11-year-old male with total anomalous systemic venous return had surgical repair except for the hepatic venous return, which drained to the left atrium. He developed progressive cyanosis and fatigue and was diagnosed with large pulmonary arteriovenous malformations (PAVMs) during cardiac catheterization with the use of bubble contrast echocardiography. After surgical redirection of hepatic venous flow to the right heart and pulmonary arterial system, resolution of these PAVMs was demonstrated clinically and by contrast echocardiography. This unique case report demonstrates the development of PAVMs with exclusion of hepatic venous return through the pulmonary vascular bed while pulsatile pulmonary blood flow remains intact. It reinforces the likelihood of the absence of an as yet unidentified hepatic vasoactive substance as the source for development of PAVMs.

Correlation of expression of cyclooxygenase-2, vascular endothelial growth factor, and peroxisome proliferator-activated receptor delta with head and neck squamous cell carcinoma

Cyclooxygenase (COX) is the rate-limiting enzyme in the formation of prostaglandins from arachidonic acid. COX exists in 2 isoforms, COX-1 and COX-2. These isoforms are encoded by separate genes and demonstrate cell-specific expression and regulation. Peroxisome proliferator-activated receptor delta (PPARdelta) is a nuclear transcription factor that is activated by prostacyclin. Vascular endothelial growth factor (VEGF) is a proangiogenic factor that is up-regulated in various tumors. Vascular endothelial growth factor has been shown to interact with COX-derived prostaglandins in angiogenesis. To better understand the roles of these genes in head and neck squamous cell carcinoma (HNSCCA), we examined the differential expression of the COX1, COX2, VEGF, and PPARdelta genes in these tumors. Tissue samples from patients with HNSCCA were analyzed for COX-1, COX-2, VEGF, and PPARdelta messenger RNAs (mRNAs) by in situ hybridization. COX-1 and COX-2 mRNAs were also evaluated with Northern blot hybridization. Immunohistochemistry was used to analyze for COX-2 and PPARdelta proteins. Results showed focal areas of accumulation for COX-2, VEGF, and PPARdelta but not COX-1 in human HNSCCA. Northern blot hybridization showed higher levels of COX-2 mRNA in HNSCCA than in normal tissue. This suggests a supportive role of COX-2 in development and/or progression of HNSCCA. In addition, PPARdelta may be a receptor for COX-2-produced prostaglandins in HNSCCA. There is a potential role for selective COX-2 inhibitors in the treatment of these lesions.

Osteocutaneous radial forearm free flap: its use without significant donor site morbidity

While the fasciocutaneous radial forearm free flap has gained increasing popularity, the osteocutaneous radial forearm free flap has been condemned because of a high rate of pathologic donor radius fracture. On the basis of studies that demonstrated increased strength in ostectomized radii after dynamic compression plating, we believed that internal fixation at the time of graft harvest would significantly reduce the incidence of donor radius fracture. This is a retrospective review of the first 54 patients undergoing osteocutaneous radial forearm free flap reconstruction of the head and neck at our institution; 52 underwent prophylactic plating of their donor radii. No clinically significant donor radius fractures have occurred in plated patients. Five asymptomatic fractures were discovered on routine radiographs and required no treatment. Objective evaluation of forearm range of motion and strength after graft harvest demonstrated excellent function compared with unoperated arms. Serial radiographs have shown remodeling and reconstitution of donor radii without localized osteopenia.

Preoperative evaluation of the radial forearm free flap patient with the objective Allen's test

OBJECTIVE

The conventional subjective Allen's test (SAT) can be problematic because of its subjective nature. The objective Allen's test (OAT) was used before surgery to reliably and objectively assess forearm vascular flow in anticipation of harvesting a radial forearm free flap (RFFF) for use in head and neck reconstruction.

STUDY DESIGN AND SETTING

Retrospective analysis of 65 patients undergoing both preoperative SAT and OAT was completed at the University of Kansas Medical Center between December 1994 and March 1998.

RESULTS

The sensitivity and specificity of the SAT compared with the sensitivity and specificity of the OAT were only 65% and 76%, respectively. In 40 patients with at least 1 forearm with a positive SAT, only 1 (2.5%) patient was found by OAT to have vasculature that would not have allowed safe RFFF harvest in either forearm. In contrast, of the 25 patients with equivocal or negative SAT results in both arms, 18 (72%) were found by OAT to be safe candidates for RFFF harvests.

CONCLUSIONS

The OAT is an objective measure of forearm vascular flow and is superior to conventional SAT in RFFF donor-site selection.

Changes in the avian cochlea after single high-dose gentamicin

PURPOSE

Define the time course of functional and anatomical damage and subsequent recovery (by regeneration) of hair cells in the chicken inner ear after a single high-dose of gentamicin.

MATERIALS AND METHODS

Broiler chicks were given a single intraperitoneal dose (200 mg/kg) of gentamicin (n = 39) or saline (n = 39). Functional status was evaluated with auditory brainstem response (ABR) thresholds before injection and before sacrifice at 2, 5, 9, 16, 21, 28, and 70 days postinjection. The cochleae were then examined with scanning electron microscopy (SEM) to assess the extent of damage along the cochlea and absolute hair cell numbers in the basal 15% of the cochlea (high-frequency region).

RESULTS

Considerable variability between animals was seen for both ABR and SEM changes. Damage was maximal at 5 days postinjection with an average ABR threshold shift of 12 dB (range -10 to 50 dB) and basal cochlear damage of 28% (range 12%-57%). Hair cell counts were significantly decreased in the basal 15% of the cochlea at 5 days. Hair cell regeneration resulted in rapid anatomical and functional recovery, but evidence of hair cell disorganization persisted at 70 days despite improved thresholds.

CONCLUSION

A single high dose of gentamicin produces a significant but variable anatomical and functional insult in the chick cochlea. Hair cell regeneration results in rapid but incomplete recovery.

Torsional strength of the radius after osteofasciocutaneous free flap harvest with and without primary bone plating

The osteocutaneous radial forearm free flap (OCRFFF) has not gained widespread popularity in mandibular reconstruction, primarily because of concerns about pathologic fracture of the weakened radius. This study examines the effectiveness of plate fixation of the radius bone after harvest of the OCRFFF as a mechanism to minimize donor-site morbidity and increase the usefulness of the OCRFFF. Matched pairs of fresh human cadaveric radius bones were used in this study. Two study groups were designed. The first group was used to define the amount of strength lost after a typical bone graft harvest. The second group was designed to demonstrate how much torsional strength was regained by the application of an orthopedic reconstruction plate. Statistically significant results were obtained for both groups. In group 1, the strength of the cut bones compared with that of the unaltered bones was significantly decreased by 82% (P = 0.016). In group 2, the cut bones reinforced with a plate were 75% stronger (P = 0.002) than the bones that were only cut. Although the radius bone is significantly weakened by the harvest of a graft, much of this strength can be regained with plate fixation of the radius.