RESUMEN
H vessels are an essential link in angiogenic-osteogenic coupling and orchestrate the process of bone healing. H vessels are critically deficient in the setting of radiation-induced fractures, which have been reported to occur in up to 25% of patients undergoing radiotherapy. By increasing H-vessel proliferation, Deferoxamine (DFO) revitalizes the physiologic response to skeletal injury and accelerates irradiated fracture repair. H-vessel quantification is therefore an important outcome measure in histologic analysis of bone healing. However, an optimized protocol for staining H vessels in formalin-fixed paraffin-embedded (FFPE) tissue sections has not been reported. With this protocol, we describe a method of staining FFPE bone samples with minimal background fluorescence and high signal-to-noise ratio. We examined mandibular specimens in a rat model of bone healing from a range of fracture conditions, including healthy bone (Fx), irradiated bone (XFx), and irradiated bone with DFO treatment (XFx-DFO). Quantitative analysis revealed a significant increase of H vessels in the XFxDFO group compared to both the Fx and XFx groups. By optimizing immunofluorescent staining of H vessels in FFPE samples across a range of fracture conditions, we offer investigators an efficacious means of producing reliable imaging for quantitative analysis of H vessels in an irradiated fracture callus.
RESUMEN
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.