Faculty Bibliography

The aesthetic and functional reconstruction of the orbital and periorbital anatomy poses a complex challenge to the reconstructive surgeon. Four clinical cases are illustrated regarding the restoration of contour, and coverage of vital structures following tumor resections.

In the radiographical evaluation of the orbital apex syndrome, standard radiographs, tomograms, and computed tomographic scans have proved useful in the demonstration of the bony pathology, especially for optic canal fractures. The limitation of these methods, however, remains in their inability to provide accurate delineation of the associated soft tissue pathology, including the presence of optic nerve sheath hematoma. Recent developments in computer technology and graphic imaging are now available to provide an accurate three-dimensional radiographical analysis of the extent of skeletal and soft tissue injury in the orbital apex syndrome. The physician, in essence, can perform a radiographical 'living autopsy'. The technique was used to evaluate a patient with bilateral apex syndrome. It clearly showed that a severe direct injury to the intracanalicular portion of the optic nerve was responsible for the development of blindness in this patient. The progression of optic nerve injury, from perineural sheath hematoma to the ultimate development of optic nerve atrophy and fibrosis, was radiographically documented

The effect of tissue expansion on iliac bone graft (onlay) survival was studied on the skulls of 35 New Zealand white rabbits. Wet bone weights at the time of grafting and at sacrifice in control animals (group I) were compared to three experimental groups. Histologic sections of the developing and resolving pseudosheath and skin envelope were performed. A self-inflating 5-mil-thick silicone expander was used for soft-tissue expansion over the rabbit snout. Bone grafts were subsequently placed in this site. Elliptical snout excision without expansion (group II) demonstrated no statistically significant difference in bone graft survival when compared to controls (group I) (p = 0.350). Full tissue expansion followed by immediate bone grafting (group III) within the pseudosheath cavity likewise demonstrated no statistically significant difference in bone graft survival when compared to controls (group I) (p = 0.500); however, when full tissue expansion was followed by delayed (2 weeks) bone grafting to allow for resolution of the giant cell inflammatory reaction of the pseudosheath (group IV), a statistically significant increased bone graft survival was achieved (p less than 0.001). The study demonstrates that the increased vascularity in the pseudosheath and in the expanded soft-tissue envelope significantly increased bone graft survival only when bone grafting was delayed

Reconstruction of a large postmastectomy irradiated chest wall defect was accomplished with a large musculocutaneous free flap of anterolateral thigh musculature and skin. The vascular anatomy of the donor area allows a very substantial flap and skin island to be transferred, leaving a well-tolerated donor defect

Lateral to medial dissection in the 'potential space' between the orbicularis oculi muscle and the septum orbitale simplifies the skin-muscle flap lower lid blepharoplasty. The procedure is safe, rapid, and atraumatic

The keystone for successful reconstruction of the medial canthal area is adequate positioning of the medial canthal complex to maintain proper intercanthal distance and apposition of the lids to the globe. This requires an understanding of the dynamics of the tripartite insertion of the MCT and its relationship to the medial orbital wall. We have previously described a technique for transnasal wiring based on anatomic studies that is anatomically and physiologically precise and that is applicable to a variety of clinical situations. Soft-tissue problems need to be dealt with on an individual basis with grafts, flaps, or a combination of these modalities

A sensitive homologous recombination strand-transfer assay is described that employs short radiolabeled double-stranded DNA fragments from the lac/polylinker region of plasmid pUC18 and (+)viral M13mp18 single-stranded DNA as substrates. Substitution of a short radiolabeled double-stranded fragment for full-length linear M13 double-stranded DNA results in an assay whose sensitivity is improved greater than 8-fold. In addition, it is less sensitive to interference from nucleases or ligases than previous assays. The assay was used to partially purify an ATP-independent strand-transfer activity from a crude nuclear extract of Drosophila melanogaster embryos. We have also tested the efficiency with which various short double-stranded DNA segments are assembled into plectonemic joints by RecA protein with this assay and found 5- to 10-fold differences. These results are interpreted as evidence for DNA sequence-specific effects in RecA-mediated homologous pairing in vitro