Navigation-Assisted Construction of an External Ear Canal Using an Autogenous Foreskin Graft

Differentiation Behaviour of Adipose-Derived Stromal Cells (ASCs) Seeded on Polyurethane-Fibrin Scaffolds In Vitro and In Vivo

Adipose-derived stromal cells (ASCs) are a promising cell source for tissue engineering and regenerative medicine approaches for cartilage replacement. For chondrogenic differentiation, human (h)ASCs were seeded on three-dimensional polyurethane (PU) fibrin composites and induced with a chondrogenic differentiation medium containing TGF-ß3, BMP-6, and IGF-1 in various combinations. In addition, in vitro predifferentiated cell-seeded constructs were implanted into auricular cartilage defects of New Zealand White Rabbits for 4 and 12 weeks. Histological, immunohistochemical, and RT-PCR analyses were performed on the constructs maintained in vitro to determine extracellular matrix (ECM) deposition and expression of specific cartilage markers. Chondrogenic differentiated constructs showed a uniform distribution of cells and ECM proteins. RT-PCR showed increased gene expression of collagen II, collagen X, and aggrecan and nearly stable expression of SOX-9 and collagen I. Rabbit (r)ASC-seeded PU-fibrin composites implanted in ear cartilage defects of New Zealand White Rabbits showed deposition of ECM with structures resembling cartilage lacunae by Alcian blue staining. However, extracellular calcium deposition became detectable over the course of 12 weeks. RT-PCR showed evidence of endochondral ossification during the time course with the expression of specific marker genes (collagen X and RUNX-2). In conclusion, hASCs show chondrogenic differentiation capacity in vitro with the expression of specific marker genes and deposition of cartilage-specific ECM proteins. After implantation of predifferentiated rASC-seeded PU-fibrin scaffolds into a cartilage defect, the constructs undergo the route of endochondral ossification.

When to Say When-Reasons to Abort Surgery for Congenital Aural Atresia

OBJECTIVE

To determine reasons for premature termination in surgery for congenital aural atresia (CAA).

STUDY DESIGN

Retrospective chart review.

SETTING

High-volume tertiary care center.

PATIENTS

Patients undergoing primary surgical repair of CAA whose surgeries were aborted for various indications.

INTERVENTION

Patients with CAA who underwent elective aural atresia surgery at the University of Virginia from July 2004 to January 2020 were identified from the medical record and an institutional database of patients with CAA. Patients undergoing revision surgery or surgery not for hearing correction were excluded. All included candidates were noted to be good surgical candidates for atresia repair based on preoperative Jahrsdoerfer score of 6 or greater. Reasons for terminating surgery prematurely were categorized by anatomical constraints (inability to identify middle ear space, position of the facial nerve, or other anatomic abnormality), stapes fixation, and middle ear and/or mastoid inflammatory disease.

MAIN OUTCOME MEASURES

Reasons for premature termination in CAA surgery.

RESULTS

Over the interval, 319 patients underwent primary surgery for CAA. Surgery was terminated prematurely without completing the primary objective in 14 patients (4.4%); surgery was terminated in 8 (57%) due to anatomic constraints, 4 (29%) due to stapes fixation, and 2 (14%) due to middle ear space and/or mastoid inflammatory disease.

CONCLUSIONS

Premature termination in surgery for CAA is a rare occurrence with careful study of the preoperative high-resolution computed tomography of the temporal bone. Of the reasons for premature termination, anatomic constraints were the most common. Knowing limitations in surgery-both technical and anatomic-is critical to optimize outcomes and prevent complications.

Preputial Grafts: The Forgotten Donor Site

BACKGROUND

The prepuce is an excellent donor site for skin grafts with minimal donor site morbidity. Full-thickness grafts are often required for correction of congenital syndactyly and in burn contractures.

METHODS

Preputial skin was used for grafting in 18 children: 5 with burn contractures and 13 with congenital syndactyly.

RESULTS

Excellent graft take was achieved with appropriate postoperative care. Postoperatively, there were occasional milia (42%) and hyperpigmentation. These grafts were noted to have superior mobility and elasticity. There was no donor site morbidity.

CONCLUSIONS

Preputial skin is accessible, easy to harvest, and hairless and has minimal donor site morbidity. It is especially well suited for the hands and fingers when elasticity of the graft is beneficial.

Controversies in aural atresia repair

PURPOSE OF REVIEW

To discuss recent controversies regarding the management of aural atresia.

RECENT FINDINGS

Management of unilateral atresia is less controversial. Candidacy for successful repair is based on high-resolution computed tomography findings and atresia grading. The bone-anchored hearing aid is a viable alternative strategy for hearing improvement. Stability of hearing results following atresia repair improves with the number of atresiaplasties performed. Development of image-guided surgery may provide benefit in atresia surgery. New unrecognized rare complications of aural atresia and atresia repair including salivary fistula and middle ear cholesteatoma are now being recognized and are manageable.

SUMMARY

Management of aural atresia continues to be difficult and surrounded by controversy. New studies and cases series may shed light on these management issues.