Tae Hui Bae

The viability of diced cartilage grafts wrapped in autogenous fascia and AlloDerm® in a rabbit model

Diced cartilage grafting has re-emerged as a popular method in aesthetic rhinoplasty since the introduction of Erols Turkish delight technique. However, an extensive literature review indicates that diced cartilage grafts with Surgicel(®) wrapping are usually absorbed and often fail to correct associated clinical problems. Recent studies show that significant foreign-body reactions occur in diced cartilage grafts wrapped in Surgicel(®), but not in grafts wrapped in fascia. However, to date, no study has addressed the histological behaviour of diced cartilage wrapped using AlloDerm(®). The primary aim of this study was to compare the viability of diced cartilage wrapped in autogenous fascia to diced cartilage wrapped in AlloDerm(®) in a rabbit model. Ear cartilage and lumbosacral fascia were obtained from six New Zealand white rabbits. Diced cartilage grafts were transplanted to three surgically created subcutaneous pockets on the backs of the rabbits. The rabbits were divided into control group and two experimental groups: control group (group I): diced cartilage (n = 6); experimental group I (group II): diced cartilage wrapped in fascia (n = 6); and experimental group II (group III): diced cartilage wrapped in AlloDerm(®) (n = 6). The grafts were observed 6 months after implantation. Histological processing of the specimens included haematoxylin-eosin (H&E), Masson trichrome, safranin-O, Van Gieson and immunohistochemical staining for glial fibrillary acidic protein. Statistical analysis was performed using the Mann-Whitney test. Results were evaluated at a p < 0.05 significance level. Our histological analysis demonstrated that the chondrocyte regeneration potential, matrix collagen content, and metaplastic bone formation of the AlloDerm(®)-treated group were significantly superior to those of the fascia-treated group. With respect to other histological parameters, the AlloDerm(®)-treated group showed better results than the fascia-treated group, but these results were not statistically significant. The results of our experimental study suggest that AlloDerm(®) may be an excellent material for diced cartilage grafting. Further studies are needed to evaluate the clinical applications of AlloDerm(®) in diced cartilage grafting.

Comparison of Absorbable Mesh Plate versus Titanium-Dynamic Mesh Plate in Reconstruction of Blow-Out Fracture: An Analysis of Long-Term Outcomes.

Background A blow-out fracture is one of the most common facial injuries in midface trauma. Orbital wall reconstruction is extremely important because it can cause various functional and aesthetic sequelae. Although many materials are available, there are no uniformly accepted guidelines regarding material selection for orbital wall reconstruction. Methods From January 2007 to August 2012, a total of 78 patients with blow-out fractures were analyzed. 36 patients received absorbable mesh plates, and 42 patients received titanium-dynamic mesh plates. Both groups were retrospectively evaluated for therapeutic efficacy and safety according to the incidence of three different complications: enophthalmos, extraocular movement impairment, and diplopia. Results For all groups (inferior wall fracture group, medial wall fractrue group, and combined inferomedial wall fracture group), there were improvements in the incidence of each complication regardless of implant types. Moreover, a significant improvement of enophthalmos occurred for both types of implants in group 1 (inferior wall fracture group). However, we found no statistically significant differences of efficacy or complication rate in every groups between both implant types. Conclusions Both types of implants showed good results without significant differences in long-term follow up, even though we expected the higher recurrent enophthalmos rate in patients with absorbable plate. In conclusion, both types seem to be equally effective and safe for orbital wall reconstruction. In particular, both implant types significantly improve the incidence of enophthalmos in cases of inferior orbital wall fractures.

The effect of botulinum toxin B pretreatment to the blood flow in the microvascular anastomosis.

BackgroundAlthough multiple factors can lead to free flap failure, vessel-related accidents are the most important. Many methods have been developed (both intraoperative and postoperative) to prevent vessel-related complications. In this article, we study the effects of a “preoperative treatment” using botulinum toxin B that could enhance the velocity and blood flow of vascular pedicles and decrease vascular accidents. MethodsTen Sprague-Dawley rats were pretreated with botulinum toxin type B at the perivascular area of the femoral vessel. Ten other rats were injected with saline as a control group. After 3 days, pedicle diameter and the peak mean frequency of blood in the pedicle were measured using laser Doppler flowmetry, and the peak mean blood velocity was calculated. We performed a “pedicle division and reanastomosis” operation to compare changes in vessel diameter and peak mean blood velocity. ResultsVessel diameter was significantly increased in the botox-pretreated group for both veins and arteries. A comparison of the deep femoral vein and artery blood velocities showed that the peak mean velocity was significantly higher in the botox group. The average increase in blood velocity was significantly larger in the botox group. ConclusionsBotulinum toxin B is helpful by influencing the microvascular environment through an increase in the blood velocity of the pedicle.

The Effects of Polydeoxyribonucleotide on the Survival of Random Pattern Skin Flaps in Rats

Background Partial or complete necrosis of a skin flap is a common problem. Polydeoxyribonucleotide (PDRN) can be extracted from trout sperm and used as a tissue repair agent. The aim of this study was to investigate whether PDRN could improve the survival of random pattern skin flaps in rats. Methods Twenty-two male Sprague-Dawley rats were randomly divided into two groups: the PDRN treatment group (n=11) and the control group (n=11). Caudally pedicled random pattern skin flaps were elevated on their dorsal skin and resutured. The treatment group received daily intraperitoneal administration of PDRN (8 mg/kg/day), and the control group received fluid vehicle (NaCl 0.9%, 8 mg/kg/day) from day 0 to day 6. On day 7, the flap survival was evaluated and the harvested tissue surrounding the demarcation line of the necrotic area was stained with H&E, anti-rat vascular endothelial cell growth factor (VEGF) antibody, and PECAM-1/CD31 antibody. Results The average necrotic area of the flap in the PDRN group was significantly smaller when compared with that of the control group. Histologic and immunohistochemical evaluation showed that granulation thickness score and VEGF-positive staining cells were marked higher in the PDRN group than in the control group. PECAM-1/CD31-positive microvascular densities were significantly higher in the PDRN group when compared with the control group. Conclusions This study confirms that PDRN improves the survival of random pattern skin flaps in rats. These results may represent a new therapeutic approach to enhancing flap viability and achieving faster wound repair.

Usefulness of Gold Thread Implantation for Crow's Feet

Background Conservative techniques designed to block or delay the aging process have been utilized in various ways for many years. However, their effects can be relatively minimal and short-term in most cases compared to surgery. The objective of this study was to evaluate the efficacy and safety of gold thread implantation for the treatment of periorbital wrinkles. Methods A total of 78 consecutive patients who showed mild to severe periorbital wrinkles were deemed appropriate candidates, including 69 women and 9 men ranging from 31 to 59 years (mean, 47 years). Six gold threads about 4 cm in length were inserted subdermally in each patient at intervals of about 0.5 cm. Follow-up assessments were performed 1, 4, and 12 weeks after the procedure. The efficacy was rated by the physician using the Wrinkle Severity Rating Scale and patients who made global assessments of changes in periorbital wrinkles using the Visual Analog Scale. Adverse events were monitored throughout the course of the study. Results The patients showed significant improvements after the procedure. There were minor complications such as foreign body sensation in the eye (2.63%) and eye pain (1.32%) that improved spontaneously without any specific treatments. Conclusions Subdermal implantation of gold thread improves the appearance of periorbital wrinkles and does not appear to have serious side effects. Insertion of gold thread may be an effective and safe method for facial rejuvenation.

Comparative study of the postoperative complications of microvascular surgery in elderly and young patients.

Free flap reconstruction of complex defects has revolutionized cancer and trauma treatment and offers a reliable and efficient method for reconstructing tissue defects. We analyzed the donor, flap, and systemic complications in an aging group and in a group of younger patients to identify whether age is an important factor in complication rates. This study was a retrospective review of the medical records of 43 consecutive patients who underwent free flap reconstructions. Patients were divided into two groups according to age (group A: younger than 60 years, group B: 60 years or older). We analyzed the free flap types and donor site, flap, and postoperative systemic complications. Statistical analyses were performed to determine the influence of age on complication rate. Donor site complications developed in three cases in group A and in three cases in group B. Flap complications occurred in 17 cases in group A and in 5 cases in group B. Systemic complications occurred in two cases in group A and in five cases in group B. Age did not have a statistically significant impact on free flap complications, and old age was not a risk factor for free flap surgery.

Early Reconstruction of Orbital Roof Fractures: Clinical Features and Treatment Outcomes

Background Orbital roof fractures are frequently associated with a high energy impact to the craniofacial region, and displaced orbital roof fractures can cause ophthalmic and neurologic complications and occasionally require open surgical intervention. The purpose of this article was to investigate the clinical features and treatment outcomes of orbital root fractures combined with neurologic injuries after early reconstruction. Methods Between January 2006 and December 2008, 45 patients with orbital roof fractures were admitted; among them, 37 patients were treated conservatively and 8 patients underwent early surgical intervention for orbital roof fractures. The type of injuries that caused the fractures, patient characteristics, associated fractures, ocular and neurological injuries, patient management, and treatment outcomes were investigated. Results The patients underwent frontal craniotomy and free bone fragment removal, their orbital roofs were reconstructed with titanium micromesh, and associated fractures were repaired. The mean follow up period was 11 months. There were no postoperative neurologic sequelae. Postoperative computed tomography scans showed anatomically reconstructed orbital roofs. Two of the five patients with traumatic optic neuropathy achieved full visual acuity recovery, one patient showed decreased visual acuity, and the other two patients completely lost their vision due to traumatic optic neuropathy. Preoperative ophthalmic symptoms, such as proptosis, diplopia, upper eyelid ptosis, and enophthalmos were corrected. Conclusions Early recognition and treatment of orbital roof fractures can reduce intracranial and ocular complications. A coronal flap with frontal craniotomy and orbital roof reconstruction using titanium mesh provides a versatile method and provides good functional and cosmetic results.

The Use of Cultured Allogenic Keratinocyte Grafting in a Patient with Epidermolysis Bullosa Simplex

Epidermolysis bullosa (EB) is a rare genetic disease that is known for continuous skin blistering caused by minor trauma. The skin blisters and bullae that develop often cause skin defects. There is no definitive treatment for EB, only symptomatic relief. We report our experience with cultured allogenic keratinocyte grafting in a newborn patient with EB simplex who had unhealed raw surfaces and was not a skin grafting candidate. The skin lesions of the patient were covered with cultured allogenic keratinocyte grafts and re-epithelialized quickly with no scarring. Allogenic keratinocyte grafting reduced pain and produced noticeable improvements in the unhealed wounds. We think that allogenic keratinocyte grafting can play an important role in the management of patients with EB simplex.

The preventive effect of topical zafirlukast instillation for peri-implant capsule formation in rabbits.

Background Capsular contracture is the most troublesome complication in breast implant surgery. Although capsule formation can be seen as a normal reaction to a foreign body, it can induce pain, hardness, deformity, and other pathologic problems. Surgical intervention is required in severe cases, but even surgery cannot guarantee a successful outcome without recurrence. This experimental study confirms that single topical administration of leukotriene antagonist zafirlukast (Accolate, Astrazeneca) reduces peri-implant capsule formation and prevents capsular contracture. Methods Twelve smooth-surfaced cohesive gel implants were implanted in New Zealand White rabbits. These miniature implants were designed to be identical to currently used products for breast augmentation. The rabbits were divided into 2 groups. In the experimental group (n=6), the implant and normal saline with zafirlukast were inserted in the submuscular pocket. In the control group (n=6), the implant and normal saline alone were used. Two months later, the implants with peri-implant capsule were excised. We evaluated capsule thickness and collagen pattern and performed immunohistochemical staining of myofibroblasts, transforming growth factor (TGF)-β1, 2. Results The thickness of the capsules in the experimental group was reduced in both dorsal and ventral directions. The collagen pattern showed parallel alignment with low density, and the number of myofibroblasts as well as the amounts of TGF-β1 and TGF-β2 were reduced in the experimental group. Conclusions We suggest that single topical administration of leukotriene antagonist zafirlukast can be helpful in reducing capsule formation and preventing capsular contracture via myofibroblast suppression, modulation of fibroblastic cytokines, and anti-inflammatory effect.

Wound contraction decreases with intravenously injected substance P in rabbits

Substance P is an injury-inducible endogenous factor for the mobilization of CD29+ stromal-like cells into circulation and that are major effectors of accelerated healing. In this study, we evaluated the effect of intravenously injected substance P on full-thickness skin wound healing as a secondary intention wound model. We made circular full-thickness skin wounds on the ears of 28 New Zealand white rabbits. They were treated with phosphate-buffered saline, or intravenous 5, 50, or 250 n mole/kg substance P at days 0 and 1. All substance P-treated groups showed a 2.6-5.4-fold higher CD29 expression and resulted in greatly decreased wound contraction and early maturation of the stroma. However, a significant decrease in wound contraction was measured only in the 5 n mole/kg treatment group. We conclude that intravenously injected substance P at 5 n mole/kg decreases wound contraction and promotes wound maturation in full-thickness skin wounds in a rabbit ear model.