Faculty Bibliography

This study reviews the various microsurgical techniques available to reanimate the paralyzed eye sphincter. Traditional as well as several innovative procedures are described that the senior author has used over the past 20 years. The methods of evaluating such outcomes are discussed and analyzed with regard to eye reanimation. An independent panel of reviewers evaluated standardized preoperative and postoperative videos documenting eye closure and blink in patients with lagophthalmos. A significant difference in overall postoperative outcome of both eye closure and blink was demonstrated. In this particular population, those patients who underwent dynamic procedures more often yielded better results than those who did not. Detailed video documentation and independent grading of outcomes of eye closure and blink are necessary to assist in developing effective surgical treatments for paralytic lagophthalmos. Accurate measurement of the results of these interventions remains a considerable challenge in the field of eye reanimation microsurgery

Computer-assisted medical imaging was used to locate the mandibular foramen and the portion of the inferior alveolar nerve canal at the level of the angle of the mandible in 19 hemimandibles of patients with craniofacial microsomia. The distance from each of these two points to the borders of the mandible was measured. The ratios of these distances to the height, anteroposterior, and buccolingual extents of the mandibular ramus were calculated. These ratios were compared among affected hemimandibles (Pruzansky classification I, n = 4; and Pruzansky classification II, n = 10), unaffected hemimandibles (n = 9), and the hemimandibles of patients with nonsyndromic, sutural synostosis (n = 7). Comparison of mean distance ratios showed that the mandibular foramen was located significantly more proximally in the affected cohort than in either the unaffected or synostosis control groups. The mandibular foramen was also located significantly closer to the buccal cortex of the mandible in the affected cohort when compared with unaffected patients. The distance from the mandibular foramen to the anterior or posterior tables of the mandible divided by the total anteroposterior distance did not vary among the three groups studied. The distance ratios between the inferior alveolar nerve canal at the level of the angle of the mandible and the mandibular borders also did not vary significantly among the groups studied. An inferior alveolar nerve canal could not be identified in any patient with Pruzansky grade III mandibular deficiency. This quantitative, three-dimensional description of points along the proximal path of the inferior alveolar nerve canal in patients with craniofacial microsomia provides useful information to assist the surgeon during osteotomy planning and may help in avoiding injury to the nerve at the time of surgery

The transverse rectus abdominis musculocutaneous (TRAM) flap is the most commonly used autogenous tissue flap for breast reconstruction. However, it may not provide sufficient volume in all patients to match the contralateral breast. Insufficient abdominal bulk or bilateral reconstructions limit the amount of tissue available for the TRAM flap. Partial flap loss from fat necrosis or radiation injury may result in contour deformities of the reconstructed breast. Additional soft-tissue augmentation and contouring may be necessary to produce adequate volume, contour, and symmetry. The authors present 7 patients who underwent latissimus dorsi flap reconstruction to correct volume and contour abnormalities that developed after TRAM flap breast reconstruction. Preservation of the serratus branch of the thoracodorsal vessels allows this flap to be used even after free TRAM flap reconstruction.

Oral squamous cell carcinoma (SCC) is characterized by invasive growth and the propensity for distant metastasis. The expression of specific adhesion receptors promotes defined interactions with the specific components found within the extracellular matrix (ECM). We previously showed that the alpha v beta 6 fibronectin receptor is highly expressed in oral SCC. Here we forced expression of the beta 6 subunit into poorly invasive SCC9 cells to establish the SCC9 beta 6 cell line and compared these two cell lines in several independent assays. Whereas adhesion to fibronectin was unaffected by the expression of beta 6, migration on fibronectin and invasion through a reconstituted basement membrane (RBM) were both increased. Function-blocking antibodies to alpha v beta 6 (10D5) reduced both migration on fibronectin and invasion through an RBM, whereas anti-alpha 5 antibodies were effective only in suppressing migration on fibronectin, not invasion. Expression of beta 6 also promoted tumor growth and invasion in vivo and modulated fibronectin matrix deposition. When grown as a co-culture with SCC9 cells, peritumor fibroblasts (PTF) organized a dense fibronectin matrix. However, fibronectin matrix assembly was decreased in co-cultures of SCC9 beta 6 cells and PTF and this decrease was reversed by the addition of function-blocking anti-alpha v beta 6 antibodies. The expression of beta 6 also resulted in increased levels of matrix metalloproteinase 3. Addition of the general MMP inhibitor GM6001 to SCC9 beta 6/PTF co-cultures dramatically increased fibronectin matrix assembly in a similar fashion as incubation with anti-alpha v beta 6 antibodies. These results demonstrate that expression of beta 6 (1) increases oral SCC cell motility and growth in vitro and in vivo; (2) negatively affects fibronectin matrix assembly; and (3) stimulates the expression and activation of MMP3. We suggest that the integrin alpha v beta 6 is a key component of oral SCC invasion and metastasis through modulation of MMP-3 activity