Precision in Oculofacial Surgery: Made-To-Specification Cast-Molded Implants in Orbital Reconstruction.

PURPOSE: To describe the utilization of customized made-to-specification porous polyethylene implants and to evaluate clinical characteristics and outcomes of patients who received these implants for unilateral orbital defects. METHODS: A retrospective review of 9 patients was performed. Three-dimensional surface models were generated from high-resolution computed tomography scans. Orbital constructs were modeled after the normal, contralateral orbits and mirrored across the vertical midline to generate the target orbital implant. Measured outcomes included globe position, extraocular motility, facial symmetry, and diplopia. RESULTS: Patients ranged 25-56 years old (mean: 37) and included 6 males and 3 females. Cases consisted of 6 orbital floor fractures due to trauma, 1 lateral wall defect after neurofibroma resection, 1 floor/medial wall defect after myxoma resection, and 1 superior orbital rim defect after intraosseous hemangioma resection. Seven patients had ≥1 prior repair. All patients had previous hard and soft tissue defects and varying degrees of restrictive globe motility. Patients exhibited improved ductions after implant placement and improved facial appearance and symmetry. Post-operatively, 1 patient was found to have a small orbital hematoma between the implant and orbital floor, resolving within weeks. CONCLUSIONS: Precision, personalized oculofacial surgery is the next wave in tailoring surgical care to the individual patient. Customizable implants are manufactured to specifically mold to an individual patient's unique bony architecture, which can lead to superior outcomes in reconstructing orbital and craniofacial bony defects. This technique is particularly useful in patients with prior unsuccessful repair.

Fat Grafting into Younger Recipients Improves Volume Retention in an Animal Model.

BACKGROUND: Soft-tissue deficits associated with various craniofacial anomalies can be addressed by fat grafting, although outcomes remain unpredictable. Furthermore, consensus does not exist for timing of these procedures. Whereas some advocate approaching soft-tissue reconstruction after the underlying skeletal foundation has been corrected, other studies have suggested that earlier grafting may exploit a younger recipient niche that is more conducive to fat graft survival. As there is a dearth of research investigating effects of recipient age on fat graft volume retention, this study compared the effectiveness of fat grafting in younger versus older animals through a longitudinal, in vivo analysis. METHODS: Human lipoaspirate from three healthy female donors was grafted subcutaneously over the calvaria of immunocompromised mice. Volume retention over 8 weeks was evaluated using micro-computed tomography at three experimental ages: 3 weeks, 6 months, and 1 year. Histologic examination was performed on explanted grafts to evaluate graft health and vascularity. Recipient-site vascularity was also evaluated by confocal microscopy. RESULTS: The greatest retention of fat graft volume was noted in the youngest group compared with both older groups (p < 0.05) at 6 and 8 weeks after grafting. Histologic and immunohistochemical analyses revealed that improved retention in younger groups was associated with greater fat graft integrity and more robust vascularization. CONCLUSION: The authors' study provides evidence that grafting fat into a younger recipient site correlates with improved volume retention over time, suggesting that beginning soft-tissue reconstruction with fat grafting in patients at an earlier age may be preferable to late correction.

Utilizing Confocal Microscopy to Characterize Human and Mouse Adipose Tissue.

Significant advances in our understanding of human obesity, endocrinology, and metabolism have been made possible by murine comparative models, in which anatomically analogous fat depots are utilized; however, current research has questioned how truly analogous these depots are. In this study, we assess the validity of the analogy from the perspective of cellular architecture. Whole tissue mounting, confocal microscopy, and image reconstruction software were used to characterize the three-dimensional structure of the inguinal fat pad in mice, gluteofemoral fat in humans, and subcutaneous adipose tissue of the human abdominal wall. Abdominal and gluteofemoral adipose tissue specimens from 12 human patients and bilateral inguinal fat pads from 12 mice were stained for adipocytes, blood vessels, and a putative marker for adipose-derived multipotent progenitor cells, cluster of differentiation 34 (CD34). Samples were whole-mounted and imaged with laser scanning confocal microscopy. Expectedly, human adipocytes were larger and demonstrated greater size heterogeneity. Mouse fat displayed significantly higher vascular density compared with human fat when normalized to adipocyte count. There was no significant difference in the concentration of CD34-positive (CD34+) stromal cells from either species. However, the mean distance between CD34+ stromal cells and blood vessels was significantly greater in human fat. Finally, mouse inguinal fat contained larger numbers of brown adipocytes than did human gluteofemoral or human abdominal fat. Overall, the basic architecture of human adipose tissue differs significantly from that of mice. Insofar as human gluteofemoral fat differs from human abdominal adipose tissue, it was closer to mouse inguinal fat, being its comparative developmental analog. These differences likely confer variance in functional properties between the two sources and thus must be considered when designing murine models of human disease.

Cell-Based Soft Tissue Reconstruction in a Hydrogel Scaffold.

BACKGROUND: Renevia is a hyaluronin-gelatin crosslinked matrix scaffold that has been studied as an alternative to adipose transfer in soft tissue reconstruction. It is designed to emulate the native extracellular matrix environment by supporting stromal vascular fraction (SVF) cell attachment, survival, and proliferation, thus promoting cell-based volume restoration. However, the concentration of incorporated cells for a clinically relevant result has yet to be determined. METHODS: Five experimental groups of seven CD-1 nude immunodeficient mice were given 250 µL grafts of the following composition: 1 million human SVF cells per mL of Renevia scaffold, 6 million human SVF cells per mL scaffold, 12 million human SVF cells per mL scaffold, Renevia scaffold-alone or human adipose tissue-alone. Volumetric analysis was conducted at discrete time points over 16 weeks using 3-dimensional ultrasound, after which time the grafts were explanted for histologic analysis. RESULTS: At the conclusion of the study at week 16, the Renevia scaffold group incorporating the highest concentration of human SVF cells (12 million cells per mL scaffold) had significantly greater volume retention compared with the 2 lower concentrations, scaffold-alone and fat-alone groups. Histology of the 12 million scaffold group revealed abundant adipocyte formation within the scaffold, exceeding that observed in the 6 million, 1 million, and scaffold-alone groups. The 12 million group also demonstrated significantly increased vascularity per CD31 staining. CONCLUSIONS: Stromal vascular fraction cells coupled with Renevia hydrogel scaffold can enhance soft tissue volume reconstruction. In this study, we observed the greatest effect with 12 million cells per mL. From the perspective of volume retention, incorporation of higher concentrations of SVF cells with Renevia may be an alternative to conventional adipose tissue grafting.

Health-Related Quality-of-Life Instruments for Pediatric Patients with Diverse Facial Deformities: A Systematic Literature Review.

BACKGROUND: Treatment for patients with diverse craniofacial conditions is complex and long-term. Craniofacial conditions profoundly influence health-related quality of life, and patient- and parent-reported outcomes provide a critical and complementary perspective on the multidisciplinary treatment of patients. However, little is known regarding the health-related quality of life among children with diverse craniofacial conditions. The purpose of this study was to systematically review the literature regarding patient- and parent-reported outcomes measures for patients with diverse craniofacial conditions. METHODS: Articles from the PubMed, PsychINFO, CINAHL, Embase/MEDLINE, Scopus, and Web of Science databases that used patient- and/or parent-reported outcome instruments in patients with diverse craniofacial conditions were reviewed. Diagnoses included were cleft lip and/or palate, craniosynostosis, microtia, craniofacial microsomia, facial vascular malformations, and congenital nevi across pediatric populations (0 to 22 years of age). RESULTS: Six hundred ninety articles were identified, and 155 were selected for inclusion. One hundred twenty different health-related quality-of-life tools were used to analyze factors such as physical, psychological, or social function. Of these, the 10 most common psychometrically tested tools were identified in 59 studies. Five tools had both parent and patient versions. Two tools were developed and validated for patients with diverse craniofacial conditions, but neither was developed for nonadolescent children. CONCLUSIONS: Many parent- and patient-reported instruments are used to measure varying health-related quality of life factors in this population, but no tool exists that was developed and psychometrically tested in different facial deformities that measures comprehensive health-related quality of life issues across all pediatric ages. This study will guide the development of new tools to measure the parent and patient health-related quality-of-life perspective in patients with diverse craniofacial conditions.

Human chorionic gonadotropin interactions with immobilized anti-hCG studied by quartz-crystal microbalance with dissipation monitoring.

Previous studies have found that commercial human pregnancy tests are often too insensitive to function to their advertised >99% accuracy. Improper orientation of proteins used for recognition of ligands in sensors can often prevent the binding site from being available to the ligand, thereby decreasing sensor sensitivity. We have developed a simple method for the immobilization of anti-human chorionic gonadotropin on a sensor surface that maximizes its sensitivity by ensuring ligand binding sites are exposed and densely packed. This surface also has an improved regenerative capacity over previously reported human chorionic gonadotropin sensors, retaining 99% of initial sensitivity after six regeneration cycles with 8M urea.