Henry C. Vasconez

Rigid fixation of the craniomaxillofacial skeleton

Part 1 Basic concepts of rigid fixation. Part 2 Implant systems for rigid fixation of the craniomaxillofacial skeleton. Part 3 Clinical applications: A-trauma B-orthognathic surgery C-congenital craniofacial deformities D-tumours.

The Viability of Autologous Fat Grafts Harvested With the LipiVage System : A Comparative Study

This study evaluates the viability of adipose aspirates harvested with the LipiVage system (Genesis Biosystems Inc, Lewisville, TX), a newly developed fat harvesting device, and determines a potentially preferred method for possible large-quantity fat graft harvesting. Adipose aspirates were harvested with the LipiVage system from the abdomen of 16 female patients (group 1, n = 8) according to the instruction by the manufacturer and with conventional liposuction (group 2, n = 8). Samples from conventional liposuction were spun at 50 g for 10 minutes and the resulting middle layer of fat was collected. All fat graft samples were evaluated with trypan blue vital staining for viable adipocyte count, glycerol-3-phosphatase dehydrogenase (G3PDH) assay for intracellular enzyme activity, and histology. In this study, group 1 had significantly higher viable adipocyte count than group 2 had (3.7 ± 0.64 versus 2.37 ± 0.56 × 106 /mL, P = 0.0021). G3PDH assay showed a marked increase of intracellular enzyme activity in group 1 compared with in group 2 (0.61 ± 0.10 versus 0.34 ± 0.13 U/mL, P = 0.00045). Histology revealed normal structures of fragmental fatty tissues in both groups. While adipose aspirates by both modalities maintain normal structure, the LipiVage system yields a greater number of viable adipocytes and sustains a higher level of intracellular enzyme activity within fat grafts and can potentially be a preferred method of choice for large-quantity fat graft harvesting.

High-energy gunshot wounds to the face.

Thirty-three patients with high-energy gunshot wounds to the face were treated at the University of Kentucky Chandler Medical Center between 1976 and 1993. Wounds were classified according to the mass and velocity of the projectile, and the range from weapon to target. More than half the injuries involved multiple facial regions. Twenty patients underwent immediate definitive reconstructive procedures. Intervals between injury and initial nondefinitive reconstruction for the other patients ranged from 1 day to 1 month. Toward the end of the study period, reconstruction was undertaken earlier and more aggressively, and included more attention to primary bone grafting and free tissue transfer. These patients developed fewer problems with infection, longterm scarring, and contracture, and they required fewer operative procedures. There was no operative mortality and none of the patients with self-inflicted injuries reattempted suicide. We conclude that early aggressive treatment of these wounds can produce better structural, functional, and rehabilitative results. Vásconez HC, Shockley ME, Luce EA. High-energy gunshot wounds to the face. Ann Plast Surg 1996;36:18-25

Two Lyophilized Polymer Matrix Recombinant Human Bone Morphogenetic Protein-2 Carriers in Rabbit Calvarial Defects

We have developed a lyophilized bone morphogenetic protein (BMP) delivery device that can be formulated to control release over 2 to 8 weeks. Bioerodible poly (d,l lactide-co-glycolide) particles loaded with 90 micrograms recombinant human BMP-2 were suspended in either carboxymethylcellulose (CMC) or methylcellulose (MC) implants. Plain CMC and MC implants served as controls, as did a nonimplanted group. A total of 40 rabbits was evaluated histologically 2, 4, or 8 weeks after receiving circular full-thickness 15-mm calvarial defects. MC appeared to prevent prolapse of periosteum and dura into the defects and did not elicit bone growth. Addition of BMP improved the result. CMC implants appeared to encourage bone growth even in the absence of BMP. When BMP was added, new bone formed earlier. CMC may influence new bone formation because it is hydrophilic. MC is less hydrophilic and may cause undue inflammation. Either can be combined with BMP to produce unitary devices that are easy to make and use.

Supraorbital roof fractures: a formidable entity with which to contend.

Supraorbital roof fractures are uncommon. The incidence has been quoted at between 1 and 5%. We believed that the incidence and morbidity of supraorbital roof fractures were actually higher. The charts of 621 inpatients with facial fractures between September 1993 and September 1995 were retrospectively reviewed. Parameters included patient characteristics; mechanism of injury; fracture characteristics; associated clinical, computed tomography, and operative findings; presence of associated skull and frontal sinus fractures; and complication rates. Fifty-eight patients (9.3%) had supraorbital roof fractures, making this one of the largest series. The average age was 31 years and the predominant mechanism of injury was motor vehicle accidents. Sixty-nine percent of the patients had associated skull fractures and 54% had frontal sinus fractures. Thirty-one of the cases were open and 32 cases were treated operatively. Dural tears were present in 14 patients, traumatic encephalocele in 3, proptosis in 6, pulsatile proptosis in 3, orbital apex syndrome in 1, persistent cerebrospinal fluid leak in 3, and meningitis in 5. A majority of the patients had associated intracranial bleeds. The incidence and morbidity of supraorbital roof fractures are much higher than previously thought. The treatment of cases should be individualized, taking into account displacement, association with skull and frontal sinus fractures, dural tears, and intracranial hemorrhage.

Subatmospheric pressure dressing as a bridge to free tissue transfer in the treatment of open tibia fractures.

Background: Free flap reconstruction performed shortly after injury is associated with reduced complications but is not always feasible. Subatmospheric pressure dressings have several beneficial effects on wounds. This study reviewed a large series of open tibia fractures to determine whether subatmospheric pressure dressings affected complication rates. Methods: One hundred five patients underwent free muscle flap reconstruction for open tibia fractures between 1991 and 2005. Patients were divided into three groups: acute (flap performed 1 to 7 days after injury), subacute (8 to 42 days after injury), and chronic (>42 days after injury). Five outcome measures were used: infectious complications, flap-related complications, surgical procedures, hospital stay, and time to bony union. The subacute group was divided into patients who underwent subatmospheric pressure dressing therapy and those who did not. Results: The complication rate in the subacute group (n = 55) was 47 percent, compared with 39 percent in the chronic group (n = 18) and 31 percent in the acute group (n = 32). Time to union was significantly shorter in the acute group than in the other groups. Subacute patients who underwent subatmospheric dressing therapy had lower overall complication (35 percent), infectious complication (6 percent), and flap-related complication rates (12 percent) than those who did not (53, 18, and 21 percent, respectively). Time to union was significantly shorter with the dressings. Conclusion: Subatmospheric pressure dressing therapy as a “bridge” to free flap reconstruction in patients with open tibia fractures was associated with reduced complication rates in the subacute group, suggesting that the dressings may effectively extend the acute period when early free tissue transfer is not possible.

Orbital floor fractures: outcomes of reconstruction.

Since the 1950s, myriad materials have been used to reconstruct orbital floor fractures. Technological advances have afforded new materials for reconstruction. Recent comparisons of materials have not been reported. Retrospective chart review was performed using current procedural terminology coding for orbital floor fractures treated between 1991 and 2009. A total of 510 charts were reviewed; 317 adult patients met criteria. Forty-seven of these patients underwent bilateral floor explorations, yielding 364 orbital floor fractures. Mean age was 33.7 years. Motor vehicle collision, assault, all-terrain vehicles, and falls constituted the majority of injury mechanisms. Impure blowouts were the most common fracture type, and zygomaticomaxillary complex fractures were the most common pattern. Materials included autologous bone, porous polyethylene, titanium, and porous polyethylene with incorporated titanium. Use of bone graft correlated with postoperative orbital dystopia and enophthalmos, as compared with alloplastic implants. Bone rigidity, unpredictable thickness, and resorption may contribute. Once the gold standard of orbital reconstruction, autologous bone may have been eclipsed by modern materials.

Infectious complications associated with the use of acellular dermal matrix in implant-based bilateral breast reconstruction.

Background: The use of acellular dermal matrix (ADM) has become a routine practice in implant-based breast reconstruction. Bilateral mastectomy is becoming more popular in cases of unilateral breast cancer. ADM has been associated with an increased incidence of complications. Methods: We identified cases of bilateral implant-based breast reconstruction over a 5-year period. Data collection included medical comorbities, details of operative management, and details of postoperative cancer treatment. Results: On univariate analysis, the use of ADM (31% vs. 7%, P = 0.018), smoking (37% vs. 13%, P = 0.045), and open wound (55% vs. 13%, P = 0.006) were significantly associated with increased risk of infection. Multivariate analysis revealed open wound as the strongest predictor of infection. Conclusions: The use of ADM is associated with an increased risk of infection in bilateral implant-based breast reconstruction. However, it does not appear to be an independent risk factor by itself.

Comparison of sterile versus nonsterile acellular dermal matrices for breast reconstruction.

BackgroundAcellular dermal matrix (ADM) has been associated with an increased incidence of complications after implant-based breast reconstruction. Recently, sterile ADM has been introduced in an attempt to minimize these complications. To analyze the impact of this product on patient outcomes, we created a database of patients undergoing implant-based breast reconstruction. MethodsPatients undergoing implant-based breast reconstruction at the University of Kentucky Medical Center from January 1, 2011, to December 31, 2011 were identified. A database of patient characteristics and outcomes was created. Outcomes investigated included mastectomy flap necrosis, dehiscence, infection, red breast, capsular contracture, hematoma, and seroma. Statistical analysis was performed. ResultsFifty-eight patients underwent breast reconstruction with implants or tissue expanders. Of the 58 patients, 9 had the sterile form of ADM placed, 25 had the original aseptic but not sterile ADM, and 24 were not reconstructed with ADM. The most frequent complication noted was seroma, occurring in 6/9 patients with sterile ADM as compared to 2/25 with the aseptic ADM. This was statistically significant (P = 0.003). ConclusionsThe use of sterile ADM is associated with a statistically significant increase in seroma formation. The etiology of this increased incidence remains unknown, but it correlates with the introduction of the sterile form of ADM at our institution. A different preparation or sterilization process, or some other variable as yet unknown, may be responsible. Further studies comparing the different forms of ADM in an animal model may serve to clarify this issue.

Cryolipolysis for fat reduction and body contouring: safety and efficacy of current treatment paradigms.

Background: Cryolipolysis is a nonsurgical technique for localized fat reduction. With the increased risk of complications from more invasive methods such as liposuction, cryolipolysis presents a promising method for nonsurgical body contouring. This study presents a systematic review of the available clinical data, with an emphasis on the efficacy, methods, safety, and complications of cryolipolysis. Methods: To identify clinical studies that assessed outcomes of cryolipolysis, a systematic review of the MEDLINE and Cochrane databases was performed with the search algorithm cryolipolysis OR cool sculpting OR fat freezing OR lipocryolysis. Results: The primary literature search returned 319 articles. After inclusion criteria were applied and additional articles were idenfied via manual review of article references, 19 studies were selected for review. Average reduction in caliper measurement ranged from 14.67 percent to 28.5 percent. Average reduction by ultrasound ranged from 10.3 percent to 25.5 percent. No significant impact on lipid levels or liver function tests after cryolipolysis treatments was noted in any study. Only mild, short-term side effects, such as erythema, swelling, and pain, were noted. Paradoxical adipose hyperplasia was described in one patient. Conclusions: Cryolipolysis is a promising procedure for nonsurgical fat reduction and body contouring and presents a compelling alternative to liposuction and other, more invasive methods. This procedure appears to be safe in the short term, with a limited side effect profile, and results in significant fat reduction when used for localized adiposities. It remains unclear whether posttreatment manual massage and multiple treatments in the same anatomic area enhance the efficacy of cryolipolysis.