Mi Kyung Kim

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.

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.

The effect of antiadhesion agent on peri-implant capsular formation in rabbits.

PurposeCapsular contracture is the most troublesome complication after aesthetic breast surgery. Capsule formation can be seen as a normal foreign body reaction caused by implant insertion into the body. Pathological capsular contracture can lead to severe symptoms including pain, tenderness, and breast distortion. Hypertrophic scar hypothesis, one of the prevailing theories, implicates hematoma, granuloma, or other factors in capsular contractures. There are also animal studies that measure adhesion-induced capsule using fibrin glue. The authors performed the experiment to evaluate reductions in capsule formation using antiadhesion agent (AAA). MethodsTwelve smooth-surfaced cohesive-gel implants were implanted in 12 New Zealand white rabbits weighing 1.8 to 2.6 kg. These 5 × 5 × 1 cm sized miniature implants were designed in accordance with products currently used for breast augmentation. After skin incision, the exposed latissimus dorsi muscle was elevated, and a submuscular pocket was made. The rabbits were divided into 2 groups. In the experimental group (n = 6), the implant and 2 mL of AAA (Guardix) were inserted into the pocket under the muscle. In the control group (n = 6), implants and 2 mL of saline were inserted into the pocket. During the 2-month follow-up period, the rabbits were imaged monthly by 3-dimensional computed tomography to study capsule formation changes. After 2 months, the animals were euthanized, and implants with peri-implant capsule were excised. We evaluated capsule thickness, collagen pattern, and myofibroblast ratio on ventral, lateral, and dorsal aspects in a blinded fashion. ResultsNo significant differences in capsule thickness or capsular contractures were observed on gross examination or 3-dimensional computed tomography. On histological evaluation, capsule was thinner on all aspects (ventral, P = 0.027; lateral, P = 0.027; dorsal, P = 0.028; all P < 0.05), the pattern of collagen had more parallel alignment at low density, and the myofibroblast ratio was lower (ventral, P = 0.009; lateral, P = 0.002; dorsal, P = 0.004; all P < 0.05) in the experimental group than in control group. ConclusionsWe suggest that AAA can be helpful in reducing capsule formation. Later, clinical trials are needed to evaluate this finding.

A comparison of triamcinolone acetonide and fibrin glue for seroma prevention in a rat mastectomy model.

BackgroundSeroma formation is one of the most common complications after flap surgery during the postoperative period. Various methods have been developed to overcome this problem, but none of them have been used successfully. Authors used topical triamcinolone acetonide to reduce seroma formation in a rat mastectomy model and compared its effectiveness with fibrin glue. MethodsIn the rat mastectomy model, the authors administered triamcinolone acetonide (experimental group I, n = 12), fibrin glue (experimental group II, n = 12), and saline (control group, n = 12) beneath the skin flap just before closure of the skin. Seroma collections were aspirated and quantified after 7 days, and histologic analysis of the skin flaps and chest walls of the rats was performed. ResultsThe experimental group I had a reduced mean seroma volume of 1.79 ± 1.32 mL, whereas the experimental group II and control group had mean seroma volumes of 4.04 ± 1.43 mL and 8.51 ± 2.60 mL, respectively (P < 0.05). In semiquantitative analysis of inflammation, inflammatory cell count in experimental group I was significantly fewer than in the other 2 groups (P < 0.001). In addition, seroma capsule formation did not occur. ConclusionsSeroma prevention using triamcinolone acetonide is simpler, more economical, and more effective than fibrin glue. In proper concentrations, triamcinolone acetonide can be used to prevent seroma formation in clinical practice.

Polydeoxyribonucleotide improves tendon healing following achilles tendon injury in rats

Tendon injuries are major musculoskeletal disorders. Polydeoxyribonucleotide activates the adenosine receptor subtype A2A, resulting in tissue growth and neogenesis. This experimental study confirms that polydeoxyribonucleotide can improve secretion of various growth factors, promote collagen synthesis, and restore tensile strength of the Achilles tendon in a rat model with Achilles tendon injury. Thirty‐six male Sprague‐Dawley rats, aged 7 weeks, were divided into two groups, and the Achilles tendon was transected and repaired using the modified Kesslers method. In the experimental group (n = 18), the rats received daily intraperitoneal administration of polydeoxyribonucleotide (8 mg/kg/day for 1, 2, or 4 weeks). The control groups received the same amount of normal saline. The rats were euthanized at 1, 2, and 4 weeks, and tissues from the repair site were harvested. The cross‐sectional area of the tendon was significantly increased at 2 and 4 weeks in polydeoxyribonucleotide group (p = 0.008 and p = 0.017, respectively). Moreover, tendons in the polydeoxyribonucleotide group were more resistant to mechanical stress at 2 and 4 weeks (p = 0.041 and p = 0.041, respectively). The staining levels of collagen type I in the experimental group were significantly stronger at 2 and 4 weeks (p = 0.026 and p = 0.009, respectively). Furthermore, higher expression levels of fibroblast growth factor, vascular endothelial growth factor, and transforming growth factor β1 were detected in the experimental group at 4 weeks (p = 0.041, p = 0.026, and p = 0.041, respectively). This study confirms that polydeoxyribonucleotide can improve the tensile strength of the rats’ Achilles tendon following injury and repair.

A Rare Case of Kimura Disease with Bilateral Parotid Involvement

Kimura disease is a rare idiopathic chronic inflammatory disorder. It typically presents in the head and neck area, whereas bilateral involvement is unusual. Its diagnosis requires it to be differentiated from other inflammatory diseases and from head and neck tumors. Treatment methods include conservative management, steroid administration, radiotherapy, and surgery; however, no single treatment of choice has been established. Herein, we report an unusual presentation of Kimura disease with bilateral parotid involvement. This case was treated by surgical excision.

Immediate reconstruction of the maxillary sinus after resection of preoperatively misdiagnosed unicystic ameloblastoma with an ectopic third molar.

We report a case of unicystic ameloblastoma associated with an ectopic third molar in the right maxillary sinus, which was misdiagnosed as a dentigerous cyst on preoperative small incisional biopsy. Surgical enucleation of the cystic lesion was performed under general anesthesia with immediate reconstruction of the maxillary sinus using titanium mesh plate. The patients postoperative recovery was uneventful, and there was no evidence of tumor recurrence during the 7-month follow-up period.

Clear cell hidradenocarcinoma of the ear helix: report of primary ear helix adnexal carcinoma with regional lymph node metastasis.

Clear cell hidradenocarcinoma is a rare tumor of eccrine sweat gland origin that has a predilection for the head and neck. It has an indolent growth pattern and a higher incidence of regional and distant metastases. Metastasizing adnexal carcinomas are rare; thus, currently there is no uniform treatment guideline. We report a case of an 89-year-old female patient with clear cell hidradenocarcinoma manifesting in the right ear helix that metastasized to the right parotid gland who was treated by wide local excision and radiation therapy.