"Longitudinal Experience Using Pedicled Buccal Fat Pad Flaps in Cleft Palatoplasty: Mitigating Velopharyngeal Insufficiency Risk and Severity"

BACKGROUND

Cleft palatoplasty commonly results in denuded maxillary bone in the lateral gutter(s) and a posterior void between oral and nasal closures. Bony exposure of the anterior palate subjects the maxilla to scarring and growth restriction, while scar contracture of the posterior void may result in velopharyngeal insufficiency (VPI) and fistula formation. Utilization of the buccal fat pad flap (BFPF) at the time of palatoplasty provides vascularized tissue over these critical areas, thereby reducing the rate of secondary surgery for speech and fistula revision.

METHODS

A single-center, retrospective review identified patients who underwent palatoplasty with or without BFPF between 1995-2015. Data collected included cleft type, surgical technique, follow-up duration, and complications. Outcomes included rate of speech surgery and palatal fistula development. Veau phenotype index was computed on a scale of 2-4 as a weighted mean to reflect the frequency of cleft type (Veau II-IV) in BFPF and non-BFPF groups.

RESULTS

Charts of 866 patients were reviewed; 212 met inclusion criteria. Of these, 101 received a BFPF. Mean follow-up duration was 11.4 years. Despite a selection bias for more severe clefts, the BFPF group had lower incidence of speech surgery (9.9% vs. 36.9%, p=0.0072). The BFPF group had more mild cases treatable with fat injection (7.9% vs. 2.7%, p=0.0346) and developed fewer fistulas (6.9% vs. 18.0%, p=0.0280).

CONCLUSION

Despite the presence of more severe clefts, the BFPF group had a significantly lower rate of speech surgery. The BFPF is a valuable adjunct in primary palatoplasty, reducing VPI and fistula formation.

H Vessel Formation as a Marker for Enhanced Bone Healing in Irradiated Distraction Osteogenesis

In the setting of bone defects, the injured vasculature and loss of hemodynamic inflow leads to hematoma formation and low oxygen tension which stimulates vascular expansion through the HIf-1α pathway. Most importantly, this pathway upregulates sprouting of type H vessels (CD31hiEmcnhi vessels). H vessels engage in direct interaction with perivascular osteoprogenitor cells (OPCs), osteoblasts, and preosteoclasts of bone formation and remodeling. This angiogenic-osteogenic coupling leads to synchronous propagation of vascular and bony tissue for regenerative healing. A growing body of literature demonstrates that H vessels constitute a large portion of bone's innate capacity for osteogenic healing. We believe that CD31hiEmcnhi vessels play a role in bone healing during distraction osteogenesis (DO). DO is a procedure that utilizes traction forces to facilitate induction of endogenous bone formation and regeneration of surrounding soft tissues such as skin, muscle, tendon, and neurovascular structures. While the H vessel response to mechanical injury is adequate to facilitate healing in normal healthy tissue, it remains inadequate to overcome the devastation of radiation. We posit that the destruction of CD31hiEmcnhi vessels plays a role in precluding DO's effectiveness in irradiated bone defect healing. We aim, therefore, to recapitulate the normal pathway of bony healing by utilizing the regenerative capacity of H vessels. We hypothesize that using localized application of deferoxamine (DFO) will enhance the H vessel-mediated vasculogenic response to radiation damage and ultimately enable osteogenic healing during DO. This discovery could potentially be exploited by developing translational therapeutics to hopefully accelerate bone formation and shorten the DO consolidation period, thereby potentially expanding DO's utilization in irradiated bone healing. Sprague-Dawley rats were divided into three groups: DO, radiation with DO (xDO), and radiation with DO and DFO implantation (xDODFO). Experimental groups received 35 Gy of radiation. All groups underwent DO. The treatment group received injections into the osteotomy site, every other day, beginning on postoperative day (POD) 4 of DFO. Animals were sacrificed on POD 40. For immunohistochemical analysis, mandibles were dissected and fixed in 4% paraformaldehyde for 48 hours, decalcified in Cal-Ex II for 2 days, dehydrated through graded ethanol of increasing concentration, and then embedded in paraffin. Samples were cut into 7-μm thick longitudinally oriented sections including the metaphysis and diaphysis. CD31 and Emcn double immunofluorescent staining were performed to evaluate the extent of CD31hiEmcnhi vessel formation. Bone sections were then stained with conjugated antibodies overnight at 4°C. Nuclei were stained with Hoechst. Slides were also double stained with Osterix and CD31 to study the quantity of H vessel-mediated recruitment of OPCs to accelerate bone healing. Images were acquired with a Nikon Ti2 widefield microscope and analyzed in NIS- Elements Advanced Research 5.41.02 software. The abundance of type H vessels is represented by the area fraction of CD31 + Emcn+ vessel area inside the regenerate sample. OPC concomitant proliferation into the distraction gap is represented by the area fraction of Osterix+ cell area inside of the regenerate sample. There were 6× more type H vessels in DO groups than in xDO groups. Localized DFO significantly increased the abundance of type H vessels of irradiated DO animals compared to xDO by 15× ( p  = 0.00133531). Moreover, the DO and xDODFO groups with higher abundance of type H vessels also demonstrated better angiogenesis and osteogenesis outcomes. Interestingly, xDODFO groups doubled the quantity of H vessel formation compared to DO, indicating a supraphysiologic response ( p  = 0.044655055). Furthermore, H vessel-mediated recruitment of OPCs mimicked the described H vessel formation trend in our study groups. Irradiated DO groups contained 3× less OPCs compared to DO controls. DFO treatment to xDO animals remediated irradiation damage by containing 12× Osterix+ cells. Finally, DFO treatment of irradiated animals quadrupled osteoprogenitor recruitment into the distraction gap compared to DO controls. In this study, we developed a novel approach to visualize CD31hiEmcnhi in paraffin sections to study DO regeneration. Normal DO demonstrated a significant upregulation of H vessel formation and associated angiogenic-osteogenic coupling. Radiation severely decreased H vessel formation along with an associated significant diminution of new bone formation and nonunion. DFO administration, however, resulted in vascular replenishment and the restoration of high quantities of CD31hiEmcnhi and OPCs, recapitulating the normal process of bony regeneration and repair. DFO treatment remediated new bone formation and bony union in irradiated fields associated with increased H vessel angiogenic-osteogenic coupling. While further studies are required to optimize this approach, the results of this study are incredibly promising for the long-awaited translation of localized DFO into the clinical arena.

Adipose-Derived Stem Cells Enhance Graft Incorporation and Mineralization in a Murine Model of Irradiated Mandibular Nonvascularized Bone Grafting

BACKGROUND

Nonvascularized bone grafting represents a practical method of mandibular reconstruction. However, the destructive effects of radiotherapy on native bone preclude the use of nonvascularized bone grafts in head and neck cancer patients. Adipose-derived stem cells have been shown to enhance bone healing and regeneration in numerous experimental models. The purpose of this study was to determine the impact of adipose-derived stem cells on nonvascularized bone graft incorporation in a murine model of irradiated mandibular reconstruction.

METHODS

Thirty isogenic rats were randomly divided into 3 groups: nonvascularized bone graft (control), radiation with nonvascularized bone graft (XRT), and radiation with nonvascularized bone graft and adipose-derived stem cells (ASC). Excluding the control group, all rats received a human-equivalent dose of radiation. All groups underwent mandibular reconstruction of a critical-sized defect with a nonvascularized bone graft from the contralateral hemimandible. After a 60-day recovery period, graft incorporation and bone mineralization were compared between groups.

RESULTS

Compared with the control group, the XRT group demonstrated significantly decreased graft incorporation (P = 0.011), bone mineral density (P = 0.005), and bone volume fraction (P = 0.001). Compared with the XRT group, the ASC group achieved a significantly increased graft incorporation (P = 0.006), bone mineral density (P = 0.005), and bone volume fraction (P = 0.013). No significant differences were identified between the control and ASC groups.

CONCLUSIONS

Adipose-derived stem cells enhance nonvascularized bone graft incorporation in the setting of human-equivalent radiation.

Computed Tomography in Patients With Craniosynostosis: A Survey to Ascertain Practice Patterns Among Craniofacial Surgeons

BACKGROUND

In patients with craniosynostosis, imaging remains up to the discretion of the plastic surgeon or neurosurgeon. To inform best practice guidelines, we sought to obtain data surrounding the frequency at which craniofacial surgeons order computed tomography (CT), as well as indications. We hypothesized that we would identify considerable variation in both imaging and associated indications.

METHODS

We surveyed members of the American Society of Maxillofacial Surgeons and the American Society of Craniofacial Surgeons to measure the frequency of preoperative and postoperative head CTs, as well as indications. Initial items were piloted with 2 craniofacial surgeons and 1 neurosurgeon, using interviews to ensure content validity. χ2 Tests were used to measure associations between operative volume, years in practice, and imaging.

RESULTS

Eighty-five craniofacial surgeons responded (13.8% response rate), with the majority (63.5%) having performed a craniosynostosis operation in the last month. Only 9.4% of surgeons never order preoperative CTs. Of those who do, the most common indications included diagnosis confirmation (31.2%) and preoperative planning (27.3%). About 25% of surgeons always obtain postoperative head CTs, usually to evaluate surgical outcomes (46.7%). Only 13.3% of respondents order 2 or more postoperative scans. Higher operative volume was associated with a lower likelihood of ordering preoperative head CTs (P = 0.008).

CONCLUSIONS

The majority of surgeons obtain preoperative head CTs, whereas only 25% obtain CTs postoperatively, often to evaluate outcomes. Because outcomes may be evaluated clinically, this is a poor use of resources and exposes children to radiation. Consensus guidelines are needed to create best practices and limit unnecessary studies.

Impact of sleep-disordered breathing on behavior and quality of life in children aged 2 to 7 years with non-syndromic cleft lip and/or palate

INTRODUCTION

Children with cleft are at high risk for sleep-disordered breathing (SDB). However, little is known about the impact of SDB in this pediatric population. The aim of this study was to investigate whether SDB play a role in behavior and quality of life (QoL) in young children with cleft.

METHODS

Cross-sectional study of 95 children aged 2.0-7.9 years with cleft palate. Parents completed a sleep (Pediatric Sleep questionnaire), a behavior (Conners' Early Childhood scale), and a generic health-related QoL (KINDL questionnaire) assessment. Symptomatic children were referred for a polysomnography (PSG).

RESULTS

Overall, 14.7% of children (49.5% boys) screened positive for SDB and 27.4% had a PSG, which identified 84.6% with sleep apnea (apnea-hypopnea index [AHI] ≥1) and 27.2% with AHI ≥5. Positive screening for SDB was associated with elevated T-scores for anxiety and physical symptoms, significant differences in mean T-scores for inattention/hyperactivity (64.2 ± 15.7 vs. 53.9 ± 11.4, p = .02), social functioning/atypical behaviour, social functioning (60.6 ± 11.7 vs. 51.9 ± 7.3, p = .004 and 59.5 ± 10.9 vs. 51.2 ± 8.0, p = .01) and mood (57.5 ± 8.2 vs. 50.7 ± 8.2, p = .03). Lower QoL scores for emotional and family well-being were also reported in children with SDB (80.7 ± 13.4 vs. 90.0 ± 8.7, p = .01, 66.7 ± 15.8 vs. 76.9 ± 11.9, p = .04). Children with AHI ≥5 compared to those with AHI ≥1 and <5 showed significant differences in mean T-score for aggressive behaviour (65.2 ± 12.1 vs. 52.3 ± 11.3, p = .04), defiant temper (62.8 ± 9.2 vs. 51.6 ± 10.2, p = .03) and lower family QoL scores (59.4 ± 15.2 vs. 77.1 ± 9.6, p = .006).

CONCLUSIONS

In children with cleft palate the presence of SDB symptoms and moderate/severe sleep apnea was associated with behavioral (internalizing/externalizing) problems and lower family well-being.

Association between habitual snoring, middle ear disease, and speech problems in young children with non-syndromic cleft palate anomalies

The purpose of this study was to investigate the association between habitual snoring (HS), middle ear disease (MED), and speech problems in children with cleft palate. This cross-sectional study included children aged 2.0-7.9 years with non-syndromic cleft palate anomalies. Parents completed the Pediatric Sleep Questionnaire and a questionnaire about MED. Audiograms and speech assessment were also conducted. Ninety-five children were enrolled; 15.2% of families reported HS, 97.6% MED, and 17.1% speech problems. HS (37.5% vs 10.3%, P = 0.007) and early episodes of MED (92.3% vs 58.2%, P = 0.021) were more likely to be reported for children with isolated cleft palate when compared to those with cleft lip and palate. Children with cleft lip and palate had a higher frequency of MED with effusion compared to those with Robin sequence (86.4% vs 57.1%, P = 0.049). The odds ratio for HS in children with ≥1 episode of MED in the last year was 7.37 (95% confidence interval 1.55-35.15, P = 0.012). There was a trend for children with speech problems reported by parents to have HS (30.8% vs 11.5%, P= 0.076). Anatomical factors play a role in the frequency of upper airway symptoms in children with cleft palate. A recent history of at least one episode of MED was associated with an increased frequency of HS.

Bone Morphogenetic Protein-2 and Demineralized Bone Matrix in Difficult Bony Reconstructions in Cleft Patients

Reconstruction of alveolar clefts includes fistula repair and bone grafting. However, bone is often harvested from the iliac crest or the skull, which can be associated with considerable donor site morbidity, and the failure rate may be as high as 20%. As such, some centers utilize bone morphogenetic protein (BMP)-2 to reconstruct the bony cleft. However, this remains an off-label use, and therefore we propose using BMP-2 only in patients with tenuous soft tissues, when the likelihood of graft failure is high. In four patients, we used BMP-2 with demineralized bone matrix (DBM) to reconstruct defects related to clefts—three patients had alveolar clefts, and the fourth patient was referred to us, with resorption of a necrotic premaxilla after premaxillary setback. In all cases, the decision was made to forego bone grafting intraoperatively given the poor quality of soft tissue and the increased risk of bone graft exposure. BMP-2 was infused onto a carrier and placed in the fistula, and Grafton DBM was then packed into the defect. In three cases, small amounts of bone from the piriform aperture were mixed with the BMP-2/DBM. After 3–7 months, all patients had generated bone in the clefts and did not require bone grafting. While we continue to prefer a “like with like” reconstruction, bone grafting has a high likelihood of failure in patients with suboptimal soft tissues or tight closures. We suggest that combining BMP-2 and DBM in higher risk patients is an excellent option to avoid bone graft loss and reoperation.

A Simplified Approach to Myelomeningocele Defect Repair

BACKGROUND

Repair of the soft tissue defect in myelomeningoceles remains challenging. The literature currently lacks a systematic approach, reporting high rates of complications. We present outcomes from the largest series to date and describe a simplified approach that minimizes morbidity and streamlines decision making.

METHODS

Patients 1 year or younger who underwent myelomeningocele repair between 2008 and 2018 were reviewed. Flap types were categorized by tissue composition. Complications were dichotomized into early and late (<30 days and >30 days postoperative, respectively). Logistic regression was used to measure the impact of flap tissue composition and skin closure technique on odds of postoperative complications.

RESULTS

Ninety-seven patients met inclusion criteria. Reoperation was required in only 3 (3.0%) patients-1 for wound dehiscence and 2 for surgical site infections. Zero cases of tethered cord or cerebrospinal fluid leak occurred. The most common minor complications were early wound complications (n = 18, 18.6%) and early infection (n = 5, 5.2%). Fascia-only flaps and muscle + other tissue flaps were not associated with higher odds of complications compared with muscle-only flaps (odds ratio [OR], 2.13; 95% confidence interval [CI], 0.53-8.50, P = 0.29; OR = 2.87, 95% CI 0.66-12.51, P = 0.16, respectively). Rhomboid flaps for skin closure were associated with higher odds of complications (OR, 4.47; 95% CI, 1.00-19.97; P = 0.05).

CONCLUSIONS

Our approach to myelomeningocele repair demonstrated no cases of secondary tethered cord or cerebrospinal fluid leak, and reoperative rates were extremely low. Because complications were unrelated to flap type, we recommend a simplified approach using any tissue type for dural coverage and 2-layer primary closure of the skin.

Assessing the Key Predictors of an Academic Career after Craniofacial Surgery Fellowship

BACKGROUND

As craniofacial fellowship positions outnumber the availability of academic craniofacial jobs, it is important to understand the factors associated with securing an academic position after fellowship. The purpose of this study was to evaluate the impact of bibliometric indices and trainee demographics on the ability to obtain a full-time academic plastic surgery position on completion of a craniofacial fellowship.

METHODS

Craniofacial fellowship graduates between 2009 and 2018 (n = 182) were identified. Initial job placement and demographic data were collected; bibliometric indices at fellowship completion were calculated. Chi-square and Fisher's exact tests and multivariable logistic regression were used to assess the association of select factors with job placement.

RESULTS

Of the 48.9 percent of fellows that secured academic positions, 39.3 percent trained at five fellowship institutions. The majority of those completing residency at top institutions for academic surgery and research entered academic positions at fellowship completion. Geography influenced academic placement, as 72.7 percent of trainees in the Northeast secured academic positions. Only 20.3 percent of fellows completed dedicated postgraduate research time, but among these, 70.3 percent entered academic jobs. The h-index (OR, 1.14; p = 0.01) and total manuscripts (OR, 1.04; p = 0.02) were significantly associated with academic practice while adjusting for other covariates.

CONCLUSIONS

Although residency training institution, geographic location, and postgraduate research may influence academic placement, the h-index and total manuscripts represent the best predictors of academic careers after craniofacial fellowship. This information is valuable for applicants who aspire to be academic craniofacial surgeons, and for programs and educators who can use these data to identify applicants with a propensity for academics.

Amifostine Prophylaxis in Irradiated Breast Reconstruction: A Study of Oncologic Safety In Vitro

BACKGROUND

Indications for adjuvant radiation therapy (XRT) in breast cancer have expanded. Although highly effective, XRT damages surrounding tissues and vasculature, often resulting in delayed or compromised breast reconstruction. Thus, effective yet safe methods of radiation injury prophylaxis would be desirable. Amifostine is a Food and Drug Administration-approved radioprotectant; however, concerns about its potential to also protect cancer remain. The purpose of this study was to evaluate the oncologic safety of amifostine (AMF) in vitro and determine its effect on human breast cancer cells in the setting of XRT.

METHODS

One ER+/PR+/Her2- (MCF-7) and two ER-/PR-Her2- (MDA-MB-231, MDA-MB-468) breast cancer cell lines were investigated. Female fibroblasts were used as controls. Cells were treated with WR-1065, the active metabolite of AMF, 20 minutes before 0Gy, 10Gy, or 20Gy XRT. Live and dead cells were quantified; percent cell death was calculated.

RESULTS

WR-1065 treatment significantly preserved viability and reduced healthy female fibroblasts death after XRT compared with untreated controls. All three breast cancer cells lines exhibited radiosensitivity with substantial cell death. Cancer cells retained their radiosensitivity despite WR-1065 pretreatment, achieving the same degree of cell death as untreated controls.

CONCLUSIONS

This study demonstrated the proficiency of AMF to selectively protect healthy cells from XRT while breast cancer cells remained radiosensitive. These results support the oncologic safety of AMF in breast cancer in vitro. Further investigation is now warranted in vivo to ascertain the translational potential of using AMF as a radioprotectant to improve breast reconstruction after radiation treatment.

Sociodemographic Predictors of Patient Age at Time of Cleft Lip and Palate Repair

Objective:

To identify the impact of sociodemographic and health variables on the age at which patients undergo cleft lip repair, cleft palate repair, and primary speech evaluation.

Design:

A retrospective, noninterventional quality assessment, and quality improvement study was designed.

Setting:

This institutional study was performed at Michigan Medicine in Ann Arbor, MI.

Patients:

All patients born between 2011 and 2014 who received surgical cleft repair, excluded those who were adopted (n = 165).

Main Outcome Measure:

The age at which patients undergo cleft lip repair, cleft palate repair, and primary speech evaluation.

Results:

Cleft lip repair was performed significantly later for patients identifying as Asian (18 weeks, P = .01), patients with Child Protective Services contact (19 weeks, P = .01), patients with a significant comorbidity (14 weeks, P = .02), and patients who underwent preliminary lip adhesion surgery (19 weeks, P < .01). Cleft palate repair was performed significantly later for patients identifying racially as Asian (19 weeks, P = .03) and other (22 weeks, P = .03). Preliminary speech and language evaluation were performed significantly later for patients identifying as black (55 weeks, P = .03) and patients diagnosed with an isolated cleft lip (71 weeks, P < .01).

Conclusions:

Timing of cleft lip, cleft palate repair, and primary speech and language evaluation are subject to variation which may be predicted by clinically accessible factors. By identifying race, Child Protective Services contact, and care variables as significant predictors of increased patient age at time of intervention, multidisciplinary cleft care teams can proactively allocate patient support resources.

Variation in the Utilization of Postoperative Computed Tomography for Patients With Nonsyndromic Craniosynostosis: A National Claims Analysis

OBJECTIVE

Routine postoperative computed tomography (CT) imaging in nonsyndromic craniosynostosis remains controversial due to the hazards of radiation exposure. The extent to which postoperative head CTs are performed remains unknown. Therefore, we sought to measure the use of postoperative CTs in this population.

DESIGN

The authors reviewed insurance claims from OptumInsight, using Current Procedural Terminology codes to identify procedures and postoperative imaging. Multilevel logistic regression was used to describe the odds of undergoing postoperative CTs, adjusting for patient and provider covariates.

PARTICIPANTS

Craniosynostosis patients who underwent reconstruction between 2001 and 2017 were reviewed. Patients older than 5 years at surgery, postoperative lengths of stay >15 days, syndromic diagnoses, operative complications within 30 days of surgery, and cranial bone grafting merited exclusion.

MAIN OUTCOME MEASURE

Odds of postoperative head CTs after cranial vault reconstruction.

RESULTS

In this cohort (n = 1150), 326 (28.4%) patients underwent postoperative head CTs. The number of CTs ranged from 0 to 14. Older age at surgery (odds ratio [OR]: 1.32, P = .002), increasing years of follow-up (OR: 1.12, P < .001), and increasing comorbidities (OR: 1.21, P = .017) were associated with postoperative CTs. After adjusting for patient factors, provider factors accounted for 31.3% of variation in imaging.

CONCLUSIONS

Over a quarter of patients underwent head CTs following reconstruction, and provider factors accounted for a large percentage of the variation. Given the risks of radiation, neurosurgeons and craniofacial surgeons face a critical need to establish postoperative imaging protocols to reduce unnecessary imaging in these vulnerable patients.

Age at Craniosynostosis Surgery and Its Impact on Ophthalmologic Diagnoses: A Single-Center Retrospective Review

BACKGROUND

Ocular abnormalities in craniosynostosis are a persistent concern for patients and providers, and some surgeons feel that early surgical intervention for synostosis alleviates the progression of ophthalmologic abnormalities. In contradistinction, the authors hypothesize that operating early will have no bearing on postoperative ophthalmologic outcomes.

METHODS

Single-suture craniosynostosis patients who underwent surgical correction between 1989 and 2015 were reviewed. Patients with multisuture craniosynostosis, syndromic diagnoses, no preoperative ophthalmology evaluation, and less than 2 years of follow-up were excluded. Logistic regression was used to determine odds of preoperative and postoperative ophthalmologic abnormalities by age, while controlling for patient-level covariates.

RESULTS

One hundred seventy-two patients met inclusion criteria. The median age at surgery was 10 months (interquartile range, 7 to 12.9 months). Increasing age at the time of surgery was associated with increased odds of preoperative ophthalmologic diagnoses (OR, 1.06; p = 0.037) but not postoperative diagnoses (OR, 1.00; p = 0.91). Increasing age at surgery was also not associated with increased odds of ophthalmologic diagnoses, regardless of timing (OR, 1.04; p = 0.08). Patients with coronal synostosis (OR, 3.94; p = 0.036) had significantly higher odds of preoperative ophthalmologic diagnoses. Patients with metopic (OR, 5.60; p < 0.001) and coronal (OR, 7.13; p < 0.001) synostosis had significantly higher odds of postoperative ophthalmologic diagnoses.

CONCLUSIONS

After reviewing an expansive cohort, associations of both overall and postoperative ophthalmologic diagnoses with age at surgery were not found. The authors' findings thus run counter to the theory that early surgical intervention lessens the likelihood of postoperative ophthalmologic diagnoses and improves ophthalmologic outcomes.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Decision-Making in Cleft-Related Surgery: A Qualitative Analysis of Patients and Caregivers

OBJECTIVE

Preference-sensitive surgical decisions merit shared decision-making, as decision engagement can reduce decisional conflict and regret. Elective cleft-related procedures are often preference sensitive, and therefore, we sought to better understand decision-making in this population.

DESIGN

Semistructured interviews were conducted to elicit qualitative data. A hierarchical codebook was developed through an iterative process in preparation for thematic analysis. Thematic analysis was performed to examine differences between patients and caregivers.

SETTING

Multidisciplinary cleft clinic at a tertiary care center.

PARTICIPANTS

Patients with cleft lip aged 8 and older (n = 31) and their caregivers (n = 31) were purposively sampled. Inability to converse in English, intellectual disability, or syndromic diagnoses resulted in exclusion.

MAIN OUTCOME MEASURES

Preferences surrounding surgical decision-making identified during thematic analysis.

RESULTS

Mean patient age was 12.7 (standard deviation: 3.1). Most had unilateral cleft lip and palate (43.8%). Three themes emerged: Insufficient Understanding of Facial Difference and Treatment, Diversity of Surgical Indications, and Barriers to Patient Autonomy. Almost half of caregivers believed their children understood their clefts, but most of these children failed to provide information about their cleft. Although many patients and caregivers acknowledged that surgery addressed function and/or appearance, patients and caregivers exhibited differences regarding the necessity of surgery. Furthermore, a large proportion of patients believed their opinions mattered in decisions, but less than half of caregivers agreed.

CONCLUSIONS

Patients with clefts desire to participate in surgical decisions but have limited understanding of their facial difference and surgical indications. Cleft surgeons must educate patients and facilitate shared decision-making.

Topical Deferoxamine Alleviates Skin Injury and Normalizes Atomic Force Microscopy Patterns Following Radiation in a Murine Breast Reconstruction Model

BACKGROUND

Breast cancer is most commonly managed with a combination of tumor ablation, radiation, and/or chemotherapy. Despite the oncologic benefit of these treatments, the detrimental effect of radiation on surrounding tissue challenges the attainment of ideal breast reconstruction outcomes. The purpose of this study was to determine the ability of topical deferoxamine (DFO) to reduce cutaneous ulceration and collagen disorganization following radiotherapy in a murine model of expander-based breast reconstruction.

METHODS

Female Sprague-Dawley rats (n = 15) were divided into 3 groups: control (expander), XRT (expander + radiation), and DFO (expander + radiation + deferoxamine [DFO]). Expanders were placed in a submusculocutaneous plane in the right upper back and ultimately filled to 15 mL. Radiation was administered via a fractionated dose of 28 Gy. Deferoxamine was delivered topically for 10 days following radiation. After a 20-day recovery period, skin ulceration and dermal type I collagen organization were analyzed.

RESULTS

Compared with control, the XRT group demonstrated a significant increase in skin ulceration (3.7% vs 43.3%, P = 0.00) and collagen fibril disorganization (26.3% vs 81.8%, P = 0.00). Compared with the XRT group, treatment with topical DFO resulted in a significant reduction in ulceration (43.3% vs 7.0%, P = 0.00) and fibril disorganization (81.8% vs 15.3%, P = 0.00). There were no statistical differences between the control and DFO groups in skin ulceration or collagen disorganization.

CONCLUSIONS

This study suggests topical DFO is capable of reducing skin ulceration and type I collagen fibril disorganization following radiotherapy. This novel application of DFO has potential to enhance expander-based breast reconstruction outcomes and improve quality of life for women suffering the devastating effects of breast cancer.

The Ethical and Professional Use of Social Media in Surgery: A Systematic Review of the Literature

Although certain medical societies have released guidelines on the use of social media, plastic surgery, with its inherent visual nature and potential for sensationalism, could benefit from increasing direction regarding the ethical use of social media. The authors hypothesized that although general platitudes for use exist in the literature, guidelines articulating the boundaries of professional use are nonspecific. Systematic searches of MEDLINE, Embase.com, and Cochrane Central Register of Controlled Trials were completed on January 18, 2017. Searches consisted of a combination of Medical Subject Headings terms and title and abstract keywords for social media and professionalism concepts. In addition, the authors manually searched the three highest impact plastic surgery journals (ending in October of 2017). Two authors screened all titles and abstracts. Studies related to clinical medicine, patient care, and the physician-patient relationship were included for full-text review. Articles related to surgery merited final inclusion. The initial search strategy yielded 954 articles, with 28 selected for inclusion after final review. The authors' manual search yielded nine articles. Of the articles from the search strategy, 10 were published in the urology literature, eight were published in general surgery, six were published in plastic surgery, three were published in orthopedic surgery, and one was published in vascular surgery. Key ethical themes emerged across specialties, although practical recommendations for professional social media behavior were notably absent. In conclusion, social media continue to be a domain with potential professional pitfalls. Appropriate use of social media must extend beyond obtaining consent, and plastic surgeons must adhere to a standard of professionalism far surpassing that of today's media culture.

Abstract 2911: The propitious dual roles of deferoxamine in head and neck cancer management

Introduction: For head and neck cancer survivors, radiotherapy (XRT) improves survivorship at a cost of impaired quality of life. XRT-induced pathologic fractures (fxs) and associated nonunions are devastating iatrogenic sequelae associated with microvascular damage in bone, yet there are no pharmacologic strategies to prevent or treat these maladies. Deferoxamine (DFO), an FDA-approved iron chelator, has been extensively investigated for its ability to promote tissue vascularization through upregulation of the HIF-1α pathway. Our laboratory has previously demonstrated improved fx healing and prevention of nonunions in radiated bone utilizing localized DFO administration. However, the role of DFO in head and neck squamous cell carcinoma (HNSCC) tumorigenesis is currently unknown. While iron is essential for normal cell proliferation, excessive iron is associated with multiple oncogenic pathways. Thus, localized iron chelation may have beneficial antitumorigenic properties. Elucidating the role of iron metabolism and correlations between iron chelation and angiogenic signaling may offer opportunities for diagnostic and treatment purposes, while simultaneously improving tissue engineering efforts for HNSCC survivors.

Methods: We surveyed the UALCAN survivorship data base for iron-related genes in HNSCC. In vitro, established MDA1986 (HPV+) and UMSCC108 (HPV-) cell lines were grown in culture. The effects of DFO were probed on 3-D tumorspheres. HIF-1α was examined by IHC, and Western blot (WB) was used to elucidate iron mediators. In vivo, MDA-1986 buccal xenografts were developed in Nu/Nu mice. Control, DFO, and XRT groups were generated, and DFO and XRT were administered as previously described. IVIS imaging and tumor volumes were used to monitor growth. UALCAN data guided the selection of iron-regulatory proteins identified by WB in excised tumors.

Results: TFRC and FTH-1 were highly upregulated, suggesting that dysregulation of iron metabolism contributes to HNSCC development. In vitro, we observed a dose-dependent decrease in 3-D tumorsphere formation and no alterations in HIF-1α expression. WB demonstrated TFRC downregulation in response to 100µM DFO in both HPV+ and - cells. In vivo, a significant decrease in tumor growth and radiance was observed with DFO treatment (comparable to XRT) when compared to untreated controls. Excised tumor WB demonstrated downregulation of TFRC, identifying it as a pivotal indicator of response to iron-chelation therapy.

Conclusion: In vitro and in vivo studies reveal that DFO exhibits antitumorigenic effects, and suggest that HIF-1α is not affected by iron chelation in HNSCC cells. Moreover, TFRC was identified as a biomarker for indicating treatment response. Our findings signify that localized DFO may have antitumorigenic effects, in addition to the previously established regenerative therapeutic effects for the treatment of XRT-induced bone pathologies.

Citation Format: Alexis Donneys, Chitra Subramanian, Jeremy Lynn, Kevin Urlaub, Kevin Kovatch, Halil S. Uygur, Mark S. Cohen, Steven R. Buchman. The propitious dual roles of deferoxamine in head and neck cancer management [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2911.

High-frequency spectral ultrasound imaging (SUSI) visualizes early post-traumatic heterotopic ossification (HO) in a mouse model

PURPOSE

Early treatment of heterotopic ossification (HO) is currently limited by delayed diagnosis due to limited visualization at early time points. In this study, we validate the use of spectral ultrasound imaging (SUSI) in an animal model to detect HO as early as one week after burn tenotomy.

METHODS

Concurrent SUSI, micro CT, and histology at 1, 2, 4, and 9weeks post-injury were used to follow the progression of HO after an Achilles tenotomy and 30% total body surface area burn (n=3-5 limbs per time point). To compare the use of SUSI in different types of injury models, mice (n=5 per group) underwent either burn/tenotomy or skin incision injury and were imaged using a 55MHz probe on VisualSonics VEVO 770 system at one week post injury to evaluate the ability of SUSI to distinguish between edema and HO. Average acoustic concentration (AAC) and average scatterer diameter (ASD) were calculated for each ultrasound image frame. Micro CT was used to calculate the total volume of HO. Histology was used to confirm bone formation.

RESULTS

Using SUSI, HO was visualized as early as 1week after injury. HO was visualized earliest by 4weeks after injury by micro CT. The average acoustic concentration of HO was 33% more than that of the control limb (n=5). Spectroscopic foci of HO present at 1week that persisted throughout all time points correlated with the HO present at 9weeks on micro CT imaging.

CONCLUSION

SUSI visualizes HO as early as one week after injury in an animal model. SUSI represents a new imaging modality with promise for early diagnosis of HO.

Sociodemographic Predictors of Missed Appointments Among Patients With Cleft Lip and Palate

Objective:

To identify disparities in compliance of and care for patients with cleft lip and/or palate (CL/P) by determining the impact of sociodemographic variables on the rate of missed appointments and Child Protective Services (CPS) involvement.

Design:

A retrospective, noninterventional quality assessment and quality improvement study were designed.

Setting:

This institutional study was performed at the University of Michigan in Ann Arbor, Michigan.

Patients:

All patients born between January 1, 2011, and December 31, 2014, who underwent surgical CL/P repair, excluding those with fewer than 5 appointments (n = 178).

Main Outcome Measure:

The rate of missed appointments, calculated as the total number of no-show appointments divided by the total number of scheduled appointments. All appointments from CL/P diagnosis to data collection were considered, including those outside of plastic surgery.

Results:

The average patient was 4.5 years of age and had 49 total scheduled appointments. The overall rate of missed appointments was 9.6%, with 66.8% of patients missing at least 1 scheduled visit. Patients who were black ( P = .04), not affiliated with a religion ( P = .01), Medicaid users ( P = .01), from an unstable social background ( P = .01), or received need-based financial assistance ( P = .00) were significantly more likely to miss appointments. Child Protective Services was involved with 3.9% of patients.

Conclusions:

Disparities exist in attendance rates among patients with CL/P, and at-risk patient populations have been identified. The allocation of cleft care resources must be efficiently planned in order to enhance the quality of care for at-risk individuals.

Timing of Furlow Palatoplasty for Patients With Submucous Cleft Palate

Background:

Submucous cleft palate (SMCP) is the most common form of cleft involving the posterior palate, resulting in variable degrees of velar dysfunction and speech disturbance. Although early surgical intervention is indicated for patients with true cleft palate, the indications for palatoplasty and timing of surgical intervention for patients with SMCP remain controversial.

Methods:

Twenty-nine patients with SMCP were retrospectively reviewed. Patients treated with Furlow palatoplasty were dichotomized based on patient age at the time of surgical correction into early speech development and late speech development. Primary outcome measures included standardized assessments of hypernasal resonance and quantitative pre- and postoperative nasometry scores. Patients managed nonoperatively were included for comparison of early and late speech outcomes.

Results:

Both early and late groups demonstrated improvement in qualitative assessment of hypernasal resonance following Furlow palatoplasty. Early and late groups also had significant improvement in pre- to postoperative nasometry scores from 7.4 to 2.3 SD from norm ( P = .01) and 6.0 to 3.6 SD from norm ( P = .02), respectively. There was no difference in postoperative nasometry scores between early and late groups, 2.3 and 3.6 SD ( P = .12).

Conclusion:

Furlow palatoplasty significantly improves the degree of hypernasality in patients with SMCP based on pre- and postoperative nasometry scores and on qualitative assessment of hypernasality. There were no differences in speech outcomes based on early compared with late operative intervention. Therefore, early palatal repair is not obligatory for optimal speech outcomes in children with SMCP and palatoplasty should be deferred until the emergence of overt velopharyngeal insufficiency.

Amifostine Treatment Mitigates the Damaging Effects of Radiation on Distraction Osteogenesis in the Murine Mandible

According to the American Society of Clinical Oncology, in 2012, more than 53,000 new cases of head and neck cancers (HNCs) were reported in the United States alone and nearly 12,000 deaths occurred relating to HNC. Although radiotherapy (XRT) has increased survival, the adverse effects can be unrelenting and their management is rarely remedial. Current treatment dictates surgical mandibular reconstruction using free tissue transfer. These complex operations entail extended hospitalizations and attendant complications often lead to delays in initiation of adjuvant therapy, jeopardizing prognosis as well as quality of life. The creation of new bone by distraction osteogenesis (DO) generates a replacement of deficient tissue from local substrate and could have immense potential therapeutic ramifications. Radiotherapy drastically impairs bone healing, precluding its use as a reconstructive method for HNC. We posit that the deleterious effects of XRT on bone formation could be pharmacologically mitigated. To test this hypothesis, we used a rodent model of DO and treated with amifostine, a radioprotectant, to assuage the XRT-induced injury on new bone formation. Amifostine had a profound salutary effect on bone regeneration, allowing the successful implementation of DO as a reconstructive technique. The optimization of bone regeneration in the irradiated mandible has immense potential for translation from the bench to the bedside, providing improved therapeutic options for patients subjected to XRT.

Role of parathyroid hormone in regeneration of irradiated bone in a murine model of mandibular distraction osteogenesis

BACKGROUND

The purpose of this study was to measure the histologic and histomorphometric effects of parathyroid hormone (PTH) treatment on irradiated bone undergoing distraction osteogenesis (DO).

METHODS

Thirty-four rats were divided into 3 groups. The control group underwent DO and the radiation control group underwent radiotherapy (RT) before DO. The PTH group underwent RT and received PTH during DO. Quantitative histology and histomorphometry were performed.

RESULTS

RT resulted in a depletion of osteocytes and increase in empty lacunae. Treatment with PTH resulted in an increase in osteocyte counts and decrease in empty lacunae (p < .05), restoring osteocytes to levels seen in nonradiated bone (p = .121). RT decreased bone volume to tissue volume (BV-TV) ratio and increased osteoid volume to tissue volume (OV-TV) ratio, signifying increased immature bone formation. PTH treatment restored OV-TV ratio to that observed in nonradiated bone.

CONCLUSION

PTH treatment of irradiated bone enhanced bone regeneration and restored osteocyte counts and OV-TV ratio to levels comparable to nonradiated bone. © 2016 Wiley Periodicals, Inc. Head Neck 39: 464-470, 2017.

Tissue engineering and regenerative approaches to improving the healing of large bone defects

Despite the high innate regenerative capacity of bone, large osseous defects fail to heal and remain a clinical challenge. Healing such defects requires the formation of large amounts of bone in an environment often rendered hostile to osteogenesis by damage to the surrounding soft tissues and vasculature. In recent years, there have been intensive research efforts directed towards tissue engineering and regenerative approaches designed to overcome this multifaceted challenge. In this paper, we describe and critically evaluate the state-of-the-art approaches to address the various components of this intricate problem. The discussion includes (i) the properties of synthetic and natural scaffolds, their use in conjunction with cell and growth factor delivery, (ii) their vascularisation, (iii) the potential of gene therapies and (iv) the role of the mechanical environment. In particular, we present a critical analysis of where the field stands, and how it can move forward in a coordinated fashion.

The role of the adaptive immune system in burn-induced heterotopic ossification and mesenchymal cell osteogenic differentiation

BACKGROUND

Heterotopic ossification (HO) is the pathologic process of extraskeletal bone formation. Although the exact etiology remains unknown, inflammation appears to catalyze disease progression. The goal of this study is to determine the impact of the adaptive immune system on HO.

METHODS

HO was induced in 8-wk-old control C57BL/6 and immunocompromised Rag1tm1Mom (Rag1 KO) male mice deficient in B- and T-lymphocytes via combined Achilles tenotomy and burn injury. Microcomputed tomography quantified the extent of HO formation at the tenotomy site. Adipose-derived mesenchymal stem cells were harvested to evaluate osteogenic differentiation potential.

RESULTS

Areas of developing HO demonstrated substantial enrichment of CD45 + leukocytes at 3 wk after injury. HO from Rag1 KO mice was substantially less mature with foci of cartilage and disorganized trabecular bone present 12 wk after injury. Rag1 KO mice formed 60% less bone compared to immunocompetent controls (4.67 ± 1.5 mm versus 7.76 ± 0.65 mm; P = 0.001). Tartrate-resistant acid phosphatase staining and immunofluorescent analysis of osteoprotegerin and nuclear factor kappa-light-chain-enhancer of activated B cells demonstrated no appreciable difference in osteoclast number or activation. Alizarin red staining in vitro demonstrated a significant decrease in osteogenic potential in immunocompromised mice compared to controls (29.1 ± 0.54 mm versus 12.1 ± 0.14 mm; P < 0.001).

CONCLUSIONS

We demonstrate a prominent role for the adaptive immune system in the development of HO. In the absence of mature B- and T-lymphocytes, HO growth and development are attenuated. Furthermore, we demonstrate that mesenchymal populations from B- and T-cell deficient mice are inherently less osteogenic. This study identifies a potential therapeutic role for modulation of the adaptive immune system in the treatment of HO.

Treatment of heterotopic ossification through remote ATP hydrolysis

Heterotopic ossification (HO) is the pathologic development of ectopic bone in soft tissues because of a local or systemic inflammatory insult, such as burn injury or trauma. In HO, mesenchymal stem cells (MSCs) are inappropriately activated to undergo osteogenic differentiation. Through the correlation of in vitro assays and in vivo studies (dorsal scald burn with Achilles tenotomy), we have shown that burn injury enhances the osteogenic potential of MSCs and causes ectopic endochondral heterotopic bone formation and functional contractures through bone morphogenetic protein-mediated canonical SMAD signaling. We further demonstrated a prevention strategy for HO through adenosine triphosphate (ATP) hydrolysis at the burn site using apyrase. Burn site apyrase treatment decreased ATP, increased adenosine 3',5'-monophosphate, and decreased phosphorylation of SMAD1/5/8 in MSCs in vitro. This ATP hydrolysis also decreased HO formation and mitigated functional impairment in vivo. Similarly, selective inhibition of SMAD1/5/8 phosphorylation with LDN-193189 decreased HO formation and increased range of motion at the injury site in our burn model in vivo. Our results suggest that burn injury-exacerbated HO formation can be treated through therapeutics that target burn site ATP hydrolysis and modulation of SMAD1/5/8 phosphorylation.

Early Development of the Mouse Morphome

INTRODUCTION

Analytical morphomics focuses on extracting objective and quantifiable data from clinical computed tomography (CT) scans to measure patients' frailty. Studies are currently retrospective in nature; therefore, it would be beneficial to develop animal models for well-controlled, prospective studies. The aim of this study is to develop an in vivo microCT protocol for the longitudinal acquisition of whole-body images suitable for morphomic analyses of bone.

METHODS

The authors performed phantom studies on 2 microCT systems (Inveon and CT120) to study tissue radiodensity and further characterize system performance for collecting animal data. The authors also describe their design of a phantom-immobilization device using phantoms and an ovariectomized (OVX) mouse.

RESULTS

The authors discovered increased consistency along the z-axis for scans acquired on the Inveon compared with CT120, and calibration by individual slice reduces variability. Objects in the field of view had more impact on measurement acquired using the CT120 compared with the Inveon. The authors also found that using the middle 80% of slices for data analysis further decreased variability, on both systems. Moreover, bone-mineral-density calibration using the QCT Pro Mini phantom improved bone-mineral-density estimates across energy spectra, which helped confirm our technique. Comparison of weekly body weights and terminal uterine mass between sham and OVX groups validated our model.

DISCUSSION

The authors present a refined microCT protocol to collect reliable and objective data. This data will be used to establish a platform for research animal morphomics that can be used to test hypotheses developed from clinical human morphomics.

Prevention of radiation-induced bone pathology through combined pharmacologic cytoprotection and angiogenic stimulation

Pathologic fractures and associated non-unions arising in previously irradiated bone are severely debilitating diseases. Although radiation is known to have deleterious effects on healthy tissue cellularity and vascularity, no clinically accepted pharmacologic interventions currently exist to target these destructive mechanisms within osseous tissues. We utilized amifostine-a cellular radioprotectant-and deferoxamine-an angiogenic stimulant-to simultaneously target the cellular and vascular niches within irradiated bone in a rat model of mandibular fracture repair following irradiation. Rats treated with combined therapy were compared to those undergoing treatment with singular amifostine or deferoxamine therapy, nontreated/irradiated animals (XFx) and non-treated/non-irradiated animals (Fx). 3D angiographic modeling, histology, Bone Mineral Density Distribution and mechanical metrics were utilized to assess therapeutic efficacy. We observed diminished metrics for all outcomes when comparing XFx to Fx alone, indicating the damaging effects of radiation. Across all outcomes, only the combined treatment group improved upon XFx levels, normalized all metrics to Fx levels, and was consistently as good as, or superior to the other treatment options (p<0.05). Collectively, our data demonstrate that pharmacologically targeting the cellular and vascular environments within irradiated bone prevents bone injury and enhances fracture healing.

Velopharyngeal Dysfunction and Sleep Apnea-A Survey to Ascertain Surgical Practice Patterns

OBJECTIVE

To determine if all cleft surgeons uniformly and adequately evaluate patients with cleft for obstructive sleep apnea (OSA) and consider OSA in treatment of velopharyngeal dysfunction (VPD).

DESIGN

A 22-question survey was administered via e-mail to 1117 surgeons who were members of the American Cleft Palate-Craniofacial Association. Logistic regression was used to determine if management was affected by years in practice, clinical volume, field of training, and region of practice.

MAIN OUTCOME MEASURES

We sought to determine if years in practice, clinical volume, region of practice, and surgical specialty affected surgeons' evaluation of OSA and their approaches to VPD.

RESULTS

A total of 231 surgeons responded (21% response rate), and 67% stated that they had trained in plastic surgery. With increasing years of practice, surgeons were less likely to refer patients for preoperative and postoperative sleep studies (P = .00 and P = .001, respectively), screen patients for sleep apnea (P = .008), or change their management based on a sleep study (P = .001). There were no significant differences in screening or testing for OSA based upon clinical volume. Among those surveyed, otolaryngologists were more likely to refer patients for postoperative sleep studies (P = .028). Surgeons in the Southeast were more likely to change their management based upon a sleep study (P = .038).

CONCLUSIONS

Statistically significant trends in screening and testing for OSA in the setting of VPD were identified by this survey. Notably, older surgeons were less likely to investigate OSA in their patients, and not all specialties equally refer for postoperative sleep studies.

Effects of aging on osteogenic response and heterotopic ossification following burn injury in mice

Heterotopic ossification (HO) is a common and debilitating complication of burns, traumatic brain injuries, and musculoskeletal trauma and surgery. Although the exact mechanism of ectopic bone formation is unknown, mesenchymal stem cells (MSCs) capable of osteogenic differentiation are known to play an essential role. Interestingly, the prevalence of HO in the elderly population is low despite the high overall occurrence of musculoskeletal injury and orthopedic procedures. We hypothesized that a lower osteogenicity of MSCs would be associated with blunted HO formation in old compared with young mice. In vitro osteogenic differentiation of adipose-derived MSCs from old (18-20 months) and young (6-8 weeks) C57/BL6 mice was assessed, with or without preceding burn injury. In vivo studies were then performed using an Achilles tenotomy with concurrent burn injury HO model. HO formation was quantified using μCT scans, Raman spectroscopy, and histology. MSCs from young mice had more in vitro bone formation, upregulation of bone formation pathways, and higher activation of Smad and nuclear factor kappa B (NF-κB) signaling following burn injury. This effect was absent or blunted in cells from old mice. In young mice, burn injury significantly increased HO formation, NF-κB activation, and osteoclast activity at the tenotomy site. This blunted, reactive osteogenic response in old mice follows trends seen clinically and may be related to differences in the ability to mount acute inflammatory responses. This unique characterization of HO and MSC osteogenic differentiation following inflammatory insult establishes differences between age populations and suggests potential pathways that could be targeted in the future with therapeutics.

A Histomorphometric Analysis of Radiation Damage in an Isogenic Murine Model of Distraction Osteogenesis

PURPOSE

The devastation radiation therapy (XRT) causes to endogenous tissue in patients with head and neck cancer can be a prohibitive obstacle in reconstruction of the mandible, demanding a better understanding of XRT-induced damage and options for reconstruction. This study investigated the cellular damage caused by radiation in an isogenic murine model of mandibular distraction osteogenesis (DO). The authors posited that radiation would result in fewer osteocytes, with increased empty lacunae and immature osteoid.

MATERIALS AND METHODS

Twenty Lewis rats were randomly assigned to a DO group (n = 10) or a XRT/DO group (n = 10). These groups underwent an osteotomy and mandibular DO across a 5.1-mm gap. XRT was administered to the XRT/DO group at a fractionated human equivalent dose of 35 Gy before surgery. Animals were sacrificed on postoperative day 40 and mandibles were harvested and sectioned for histologic analysis.

RESULTS

Bone that underwent radiation showed a significantly decreased osteocyte count and complementary increase in empty lacunae compared with non-XRT bone (P = .019 and P = .000). In addition, XRT bone exhibited increased immature osteoid and decreased mature woven bone compared with nonradiated bone (P = .001 and P = .003, respectively). Furthermore, analysis of the ratio of immature osteoid to woven bone volume exhibited a significant increase in the XRT bone, further showing the devastating damage from XRT (P = .001).

CONCLUSION

These results clearly show the cellular diminution that occurs as a result of radiation. This foundational study provides the groundwork on which to investigate cellular therapies in an immuno-privileged model of mandibular DO.

Translational treatment paradigm for managing non-unions secondary to radiation injury utilizing adipose derived stem cells and angiogenic therapy

BACKGROUND

Bony non-unions arising in the aftermath of collateral radiation injury are commonly managed with vascularized free tissue transfers. Unfortunately, these procedures are invasive and fraught with attendant morbidities. This study investigated a novel, alternative treatment paradigm utilizing adipose-derived stem cells (ASCs) combined with angiogenic deferoxamine (DFO) in the rat mandible.

METHODS

Rats were exposed to a bioequivalent dose of radiation and mandibular osteotomy. Those exhibiting non-unions were subsequently treated with surgical debridement alone or debridement plus combination therapy. Radiographic and biomechanical outcomes were assessed after healing.

RESULTS

Significant increases in biomechanical strength and radiographic metrics were observed in response to combination therapy (p < .05). Importantly, combined therapy enabled a 65% reduction in persisting non-unions when compared to debridement alone.

CONCLUSION

We support the continued investigation of this promising combination therapy in its potential translation for the management of radiation-induced bony pathology. © 2015 Wiley Periodicals, Inc. Head Neck 38: E837-E843, 2016.

Dose-response effect of human equivalent radiation in the mandible

BACKGROUND

Despite widespread use of adjuvant irradiation for head and neck cancer, the extent of damage to the underlying bone is not fully understood but is associated with pathologic fractures, nonunion, and osteoradionecrosis. The authors' laboratory previously demonstrated that radiation significantly impedes new bone formation in the murine mandible. We hypothesize that the detrimental effects of human equivalent radiation on the murine mandible results in a dose-dependent degradation in traditional micro-computed tomography (micro-CT) metrics.

METHODS

Fifteen male Sprague-Dawley rats were randomized into 3 radiation dosage groups: low (5.91 Gy), middle (7 Gy), and high (8.89 Gy), delivered in 5 daily fractions. These dosages approximated 75%, 100%, and 150%, respectively, of the biologically equivalent dose that the human mandible receives during radiation treatment. Hemimandibles were harvested 56 days after radiation and scanned using micro-CT. Bone mineral density, tissue mineral density, and bone volume fraction were measured along with microdensitometry measurements.

RESULTS

Animals demonstrated dose-dependent adverse effects of mucositis, alopecia, weight loss, and mandibular atrophy with increasing radiation. Traditional micro-CT parameters were not sensitive enough to demonstrate statistically significant differences between the radiated groups; however, microdensitometry analysis showed clear differences between radiated groups and statistically significant changes between radiated and nonradiated groups.

CONCLUSIONS

The authors report dose-dependent and clinically significant adverse effects of fractionated human equivalent radiation to the murine mandible. The authors further report the limited capacity of traditional micro-CT metrics to adequately capture key changes in bone composition and present microdensitometric histogram analysis to demonstrate significant radiation-induced changes in mineralization patterns.

Raman spectroscopy delineates radiation-induced injury and partial rescue by amifostine in bone: a murine mandibular model

Despite its therapeutic role in head and neck cancer, radiation administration degrades the biomechanical properties of bone and can lead to pathologic fracture and osteoradionecrosis. Our laboratories have previously demonstrated that prophylactic amifostine administration preserves the biomechanical properties of irradiated bone and that Raman spectroscopy accurately evaluates bone composition ex vivo. As such, we hypothesize that Raman spectroscopy can offer insight into the temporal and mechanical effects of both irradiation and amifostine administration on bone to potentially predict and even prevent radiation-induced injury. Male Sprague-Dawley rats (350-400 g) were randomized into control, radiation exposure (XRT), and amifostine pre-treatment/radiation exposure groups (AMF-XRT). Irradiated animals received fractionated 70 Gy radiation to the left hemi-mandible, while AMF-XRT animals received amifostine just prior to radiation. Hemi-mandibles were harvested at 18 weeks after radiation, analyzed via Raman spectroscopy, and compared with specimens previously harvested at 8 weeks after radiation. Mineral (ρ958) and collagen (ρ1665) depolarization ratios were significantly lower in XRT specimens than in AMF-XRT and control specimens at both 8 and 18 weeks. amifostine administration resulted in a full return of mineral and collagen depolarization ratios to normal levels at 18 weeks. Raman spectroscopy demonstrates radiation-induced damage to the chemical composition and ultrastructure of bone while amifostine prophylaxis results in a recovery towards normal, native mineral and collagen composition and orientation. These findings have the potential to impact on clinical evaluations and interventions by preventing or detecting radiation-induced injury in patients requiring radiotherapy as part of a treatment regimen.

Obstructive sleep apnea pretreatment and posttreatment in symptomatic children with congenital craniofacial malformations

STUDY OBJECTIVES

Obstructive sleep symptoms are common in children with craniofacial malformations (CFM). However objective data about obstructive sleep apnea (OSA) is still limited. The aims of this study were to investigate the frequency of OSA in symptomatic children with CFM and to determine improvement in severity of OSA after treatment.

METHODS

Symptomatic children with CFM referred for a diagnostic polysomnogram (PSG) were identified. Obstructive sleep apnea was defined as an apnea/hypopnea index (AHI) ≥ 1, with moderate/severe OSA as an AHI ≥ 5.

RESULTS

Overall, 151 symptomatic children were identified; 87% were diagnosed with OSA, of whom 24% had moderate-to-severe OSA. Children with syndromic CFM, compared to non-syndromic CFM, were more likely to have an AHI ≥ 5 (syndromic 33% vs. non-syndromic 15%, p = 0.02). Of the 131 children with OSA, 64 were treated and 32 returned for a posttreatment PSG, with 22 treated with either positive airway pressure (PAP) or adenotonsillectomy (AT). Children treated with PAP demonstrated a decrease in AHI from 6.2 to 3.5 (p = 0.057) and an increase in SpO2 from 89.1% to 91.1% (p = 0.091). There were no significant improvements for those in the AT group for either AHI (2.5 to 1.8, p = 0.19) or SpO2 (90.4% to 91.3%, p = 0.46). Normalization of the AHI (AHI < 1) occurred in only one child in each group (7% and 14% of the PAP and AT groups, respectively).

CONCLUSIONS

The vast majority of children with CFM referred for OSA evaluation are found to have objective evidence of OSA and a quarter of children have moderate-to-severe OSA. It is likely that many children with underlying OSA are not identified and referred for evaluation. Residual OSA after treatment is common in children with CFM.

Prophylactic administration of Amifostine protects vessel thickness in the setting of irradiated bone

Although often beneficial in the treatment of head and neck cancer (HNC), radiation therapy (XRT) leads to the depletion of vascular supply and eventually decreased perfusion of the tissue. Specifically, previous studies have demonstrated the depletion of vessel volume fraction (VVF) and vessel thickness (VT) associated with XRT. Amifostine (AMF) provides protection from the detrimental effects of radiation damage, allowing for reliable post-irradiation fracture healing in the murine mandible. The purpose of this study is to investigate the prophylactic ability of AMF to protect the vascular network in an irradiated field. Sprague-Dawley rats (n = 17) were divided into 3 groups: control (C, n = 5), radiated (XRT, n = 7), and radiated mandibles treated with Amifostine (AMF XRT, n = 5). Both groups receiving radiation underwent a previously established, human equivalent dose of XRT totaling 35 Gy, equally fractionated over 5 days. The AMF XRT group received a weight dependent (0.5 mg AMF/5 g body weight) subcutaneous injection of AMF 45 min prior to XRT. Following a 56-day recovery period, mandibles were perfused, dissected, and imaged with μCT. ANOVA was used for comparisons between groups and p < 0.05 was considered statistically significant. Stereologic analysis demonstrated a significant and quantifiable restoration of VT in AMF treated mandibles as compared to those treated with radiation alone (0.061 ± 0.011 mm versus 0.042 ± 0.004 mm, p = 0.027). Interestingly, further analysis demonstrated no significant difference in VT between control mandibles and those treated with AMF (0.067 ± 0.016 mm versus 0.061 ± 0.011 mm, p = 0.633). AMF treatment also showed an increase in VVF, however those results were not statistically significant from VVF values demonstrated by the XRT group. Our data support the contention that AMF therapy acts prophylactically to protect vessel thickness. Based on these findings, we support the continued investigation of this treatment paradigm in its potential translation for the prevention of vascular depletion after radiotherapy.

Morphomic analysis as an aid for preoperative risk stratification in patients undergoing major head and neck cancer surgery

BACKGROUND

Patients undergoing major head and neck cancer surgery (MHNCS) may develop significant postoperative complications. To minimize the risk of complications, clinicians often assess multiple measures of preoperative health in terms of medical comorbidities. One emerging method to decrease surgical complications is preoperative assessment of patient frailty measured by specific tissue characteristics. We hypothesize that morphomic characteristics of the temporalis region serve as predictive markers for the development of complications after MHNCS.

METHODS

We performed a retrospective review of 69 patients with available computed tomography (CT) imaging who underwent MHNCS from 2006-2012. To measure temporalis region characteristics, we used morphomic analysis of available preoperative CT scans to map out the region. All available CT scans had been performed as part of the patient's routine work-up and were not ordered for morphomic analysis. We describe the correlation among temporalis fat pad volume (TFPV), mean zygomatic arch thickness, and incidence of postoperative complications.

RESULTS

We noted significant difference in the zygomatic bone thickness and TFPV between patients who had medical complications, surgical complications, or total major complications and those who did not. Furthermore, by use of binary logistic regression, our data suggest decreased TFPV and zygomatic arch thickness are stronger predictors of developing postoperative complications than previously studies preoperative characteristics.

CONCLUSIONS

We describe morphomic analysis of the temporalis region in patients undergoing MHNCS to identify patients at risk for complications. Regional anatomic morphology may serve as a marker to objectively determine a patient's overall health. Use of the temporalis region is appropriate in patients undergoing MHNCS because of the availability of preoperative scans as part of routine work up for head and/or neck cancer.

Targeting of ALK2, a Receptor for Bone Morphogenetic Proteins, Using the Cre/lox System to Enhance Osseous Regeneration by Adipose-Derived Stem Cells

Access to readily available autogenous tissue that regenerates bone would greatly improve clinical care. We believe the osteogenic phenotype caused by mutations in ALK2 can be harnessed in adipose-derived stem cells (ASCs) to improve bone tissue engineering. We set out to demonstrate that ALK2 may serve as a novel target to (a) improve in vitro ASC osteogenic differentiation and (b) enhance in vivo bone regeneration and calvarial healing. Transgenic mice were designed using the Cre/lox system to express constitutively active ALK2 (caALK2) with ubiquitously inducible Cre expression after tamoxifen exposure. ASCs from caALK2+/- and caALK2-/-(control) mice were exposed to tamoxifen and assessed for pro-osteogenic gene expression, bone morphogenetic protein (BMP) signaling, and osteogenic differentiation. Next, ASCs collected from these transgenic mice were analyzed in vivo using a calvarial defect model and analyzed by micro-computed tomography (micro-CT) and histology. ASCs from caALK2+/-mice had increased BMP signaling as demonstrated by upregulation of pSmad 1/5. ASCs from caALK2+/-mice had enhanced bone signaling and osteogenic differentiation compared with caALK2-/-mice (n=4, p<.05). Transcription of pro-osteogenic genes at day 7 was significantly higher in ASCs from caALK2-overexpressing mice (Alp, Runx2, Ocn, Opn) (n=4, p<.05). Using micro-CT and histomorphometry, we found that bone formation was significantly higher in mice treated with caALK2-expressing ASCs in vivo. Using a novel transgenic mouse model, we show that expression of constitutively active ALK2 receptor results in significantly increased ASC osteogenic differentiation. Furthermore, we demonstrate that this increased ASC differentiation can be harnessed to improve calvarial healing.

Vascular analysis as a proxy for mechanostransduction response in an isogenic, irradiated murine model of mandibular distraction osteogenesis

INTRODUCTION

Head and neck cancer is a debilitating and disfiguring disease. Although numerous treatment options exist, an array of debilitating side effects accompany them, causing physiological and social problems. Distraction osteogenesis (DO) can avoid many of the pathologies of current reconstructive strategies; however, due to the deleterious effects of radiation on bone vascularity, DO is generally ineffective. This makes investigating the effects of radiation on neovasculature during DO and creating quantifiable metrics to gauge the success of future therapies vital. The purpose of this study was to develop a novel isogenic rat model of impaired vasculogenesis of the regenerate mandible in order to determine quantifiable metrics of vascular injury and associated damage.

METHODS

Male Lewis rats were divided into two groups: DO only (n=5) AND Radiation Therapy (XRT)+DO (n=7). Afterwards, a distraction device was surgically implanted into the mandible. Finally, they were distracted a total of 5.1mm. Animals were perfused with a radiopaque casting agent concomitant with euthanasia, and subsequently demineralization, microcomputed tomography, and vascular analysis were performed.

RESULTS

Vessel volume fraction, vessel thickness, vessel number, and degree of anisotropy were diminished by radiation. Vessel separation was increased by radiation.

CONCLUSION

The DO group experienced vigorous vessel formation during distraction and neovascularization with a clear, directional progression, while the XRT/DO group saw weak vessel formation during distraction and neovascularization. Further studies are warranted to more deeply examine the impairments in osteogenic mechanotransductive pathways following radiation in the murine mandible. This isogenic model provides quantifiable metrics for future studies requiring a controlled approach to immunogenicity.

Targeting angiogenesis as a therapeutic means to reinforce osteocyte survival and prevent nonunions in the aftermath of radiotherapy

BACKGROUND

Radiotherapy (XRT) exerts detrimental collateral effects on bone tissue through mechanisms of vascular damage and impediments to osteocytes, ultimately predisposing patients to the debilitating problems of late pathologic fractures and nonunions. We posit that angiogenic therapy will reverse these pathologic effects in a rat model of radiated fracture healing.

METHODS

Three groups of rats underwent mandibular osteotomy. Radiated groups received a fractionated 35-Gy dose before surgery. The deferoxamine (DFO) group received local injections postoperatively. A 40-day healing period was allowed before histology. Analysis of variance (ANOVA; p < .05) was used for group comparisons.

RESULTS

Radiated fractures revealed a significantly decreased osteocyte count and corresponding increase in empty lacunae when compared to nonradiated fractures (p = .001). With the addition of DFO, these differences were not appreciated. Further, a 42% increase in bony unions was observed after DFO therapy.

CONCLUSION

Targeting angiogenesis is a useful means for promoting osteocyte survival and preventing bone pathology after XRT.

Association between symptoms of sleep-disordered breathing and speech in children with craniofacial malformations

STUDY OBJECTIVE

Sleep-disordered breathing (SDB) and speech difficulties are common problems in children with craniofacial malformations (CFM). The present study was designed to investigate whether resonance issues identified during speech assessment are associated with parental report of SDB symptoms in children with CFM.

METHODS

Children aged 2-18 years with congenital CFM attending at the Craniofacial Anomalies Program from March 2007 to April 2011 were screened for SDB symptoms using the Sleep-Related Breathing Disturbance Scale of the Pediatric Sleep Questionnaire. Speech evaluation, based on the Pittsburgh Weighted Speech Scale score, was the tool used to investigate velopharyngeal dysfunction (VPD) based on speech perceptual assessment.

RESULTS

A total of 488 children with congenital CFM were included. Overall 81% were Caucasian and 24% were overweight/obese. Twenty-four percent of children screened positive for SDB and 35% had VPD. Children with VPD were no more likely to screen positive for SDB than children without VPD (26% vs. 23%, p = 0.38). However, children with previous sphincter pharyngoplasty (SP) were more likely to have hyponasality (51% vs. 12%, p = 0.0001) and reduced or absent nasal emission (33% vs. 16%, p = 0.008). In a logistic regression, the adjusted odds ratio for SDB for those with hyponasality was 2.10 (95%CI 1.21-3.61, p = 0.008) and for those with reduced or absent nasal emission was 1.75 (95%CI 1.06-2.88, p = 0.028).

CONCLUSION

Symptoms of sleep disordered breathing are common in children with craniofacial malformations especially if they have undergone sphincter pharyngoplasty; many of these children can be identified by measures of resonance on routine speech evaluation.

The face of sleepiness: improvement in appearance after treatment of sleep apnea

STUDY OBJECTIVES

Anecdote but no formal evidence suggests that facial appearance improves after hypersomnolent patients with obstructive sleep apnea are treated. We investigated whether masked volunteer raters can identify post- rather than pre-treatment images as looking more alert, and whether impressions are predicted by any objective changes on highly precise 3-dimensional digital photogrammetry.

METHODS

Participants included 20 adults with obstructive sleep apnea on polysomnography and excessive sleepiness on Epworth Sleepiness Scales. Photogrammetry was performed before and after ≥ 2 months of adherent use of positive airway pressure. Twenty-two raters then assessed pre- and post-treatment facial images, paired side-by-side in random order.

RESULTS

Subjects included 14 men and 6 women, with mean age 45 ± 11 (SD) years and mean baseline apnea/hypopnea index of 26 ± 21. The 22 raters twice as often identified post-treatment rather than pre-treatment images to look more alert (p = 0.0053), more youthful (p = 0.026), more attractive (p = 0.0068), and more likely to reflect the treated state (p = 0.015). Photogrammetry documented post-treatment decreases in forehead surface volume and decreased infraorbital and cheek redness, but no narrowing of the interpalpebral fissure. Decreased deep NREM sleep at baseline, and pre- to post-treatment decrements in facial redness showed promise as predictors of improved subjective ratings for alertness.

CONCLUSIONS

Patients with obstructive sleep apnea are perceived to appear more alert, more youthful, and more attractive after adherent use of positive airway pressure. Objective changes in facial surface volume and color were identified. Post-treatment decrements in redness may inform subjective impressions of improved alertness.

Symptoms of sleep disordered breathing in children with craniofacial malformations

STUDY OBJECTIVE

The purpose of this study was to investigate the frequency of sleep disordered breathing (SDB) symptoms in a clinical sample of children with congenital craniofacial malformations (CFM) followed at a tertiary medical center and non-selected for sleep problems.

METHODS

Cross-sectional study of 575 children aged 2-18 years followed at the Craniofacial Anomalies Program between March 2007 and May 2011. The Sleep-Related Breathing Disturbance scale of the Pediatric Sleep Questionnaire was used to screen for SDB, snoring, and sleepiness. A cutoff value ≥ 0.33 of the total answered questions identified children with positive screening for SDB symptoms.

RESULTS

Overall, 25% of children screened positive for SDB, 28% for snoring, and 20% for sleepiness. In children with non-syndromic CFM, those with Robin sequence had the highest frequency of SDB, snoring, and sleepiness (43%, 44%, and 38%, respectively). In children with syndromic CFM, velocardiofacial/ DiGeorge syndrome had the highest frequency of SDB and sleepiness (48% and 43%, respectively). Children with Treacher Collins had the highest frequency of snoring (83%). The presence of cleft palate was not associated with an increased frequency of SDB symptoms. Nevertheless, children with syndromic CFM, compared to those with non-syndromic CFM, had a higher SDB score (0.27 ± 0.21 vs.0.21 ± 0.19, p = 0.003) and were more likely to have sleepiness (26% vs. 18%, p = 0.05).

CONCLUSIONS

Congenital craniofacial malformations in children are associated with high risk for SDB symptoms. Our findings should encourage a high index of suspicion for SDB in children with CFM, with a low threshold for further testing and close follow-up.

CITATION

Moraleda-Cibrián M; Edwards SP; Kasten SJ; Berger M; Buchman SR; O'Brien LM. Symptoms of sleep disordered breathing in children with craniofacial malformations.