Kyung S. Koh

Frontal soft tissue analysis using a 3 dimensional camera following two-jaw rotational orthognathic surgery in skeletal class III patients.

Although two dimensional cephalometry is the standard method for analyzing the results of orthognathic surgery, it has potential limits in frontal soft tissue analysis. We have utilized a 3 dimensional camera to examine changes in soft tissue landmarks in patients with skeletal class III dentofacial deformity who underwent two-jaw rotational setback surgery. We assessed 25 consecutive Asian patients (mean age, 22 years; range, 17-32 years) with skeletal class III dentofacial deformities who underwent two-jaw rotational surgery without maxillary advancement. Using a 3D camera, we analyzed changes in facial proportions, including vertical and horizontal dimensions, facial surface areas, nose profile, lip contour, and soft tissue cheek convexity, as well as landmarks related to facial symmetry. The average mandibular setback was 10.7 mm (range: 5-17 mm). The average SNA changed from 77.4° to 77.8°, the average SNB from 89.2° to 81.1°, and the average occlusal plane from 8.7° to 11.4°. The mid third vertical dimension changed from 58.8 mm to 57.8 mm (p = 0.059), and the lower third vertical dimension changed from 70.4 mm to 68.2 mm (p = 0.0006). The average bigonial width decreased from 113.5 mm to 109.2 mm (p = 0.0028), the alar width increased from 34.7 mm to 36.1 mm (p-value = 0.0002), and lip length was unchanged. Mean mid and lower facial surface areas decreased significantly, from 171.8 cm(2) to 166.2 cm(2) (p = 0.026) and from 71.23 cm(2) to 61.9 cm(2) (p < 0.0001), respectively. Cheek convexity increased significantly, from 171.8° to 155.9° (p = 0.0007). The 3D camera was effective in frontal soft tissue analysis for orthognathic surgery, and enabled quantitative analysis of changes in frontal soft tissue landmarks and facial proportions that were not possible with conventional 2D cephalometric analysis.

Nasalance scores for normal Korean-speaking adults and children

There are numerous nasometric studies to date, including normative nasalance scores for various languages as well as nasometric differences in age, gender, race and region except the Korean language. In this regard, we sought to establish normative nasalance scores for Koreans. We created speech samples based on the everyday use of phonemes in the Korean language which were syntactically simple for children. In addition, we analysed nasometric features based on age and gender and confirmed test-retest reliability. The study included 108 children (54 girls and 54 boys, aged 7-11 years) and 108 adults (54 women and 54 men, aged 18-29 years) with normal articulation, resonance, voice and hearing. Nasometer II 6400 was used to measure the nasalance scores. The subjects read or repeated three speech stimuli, each consisting of 33, 36 and 24 syllables: (1) an oral passage devoid of nasal consonants, (2) an oro-nasal passage and (3) nasal sentences. For each stimulus, mean nasalance scores were obtained and gender or age dependence was analysed, using two-way analyses of variance. The mean nasalance scores for the oral passage, oro-nasal passage and nasal sentences were 11.69% (standard deviation (SD) 3.68), 34.04% (SD 4.88) and 63.72% (SD 6.07), respectively. Female speakers exhibited significantly higher nasalance scores than male speakers on the oro-nasal passage (p = 0.000) and nasal sentences (p = 0.004). Children exhibited significantly higher nasalance scores than adults on nasal sentences (p = 0.000). The nasalance scores in children and females were a little higher. Korean normative data will provide reference information in the evaluation and treatment of resonance problems.

Mirror-Imaged Rapid Prototype Skull Model and Pre-Molded Synthetic Scaffold to Achieve Optimal Orbital Cavity Reconstruction

PURPOSE Reconstruction of traumatic orbital wall defects has evolved to restore the original complex anatomy with the rapidly growing use of computer-aided design and prototyping. This study evaluated a mirror-imaged rapid prototype skull model and a pre-molded synthetic scaffold for traumatic orbital wall reconstruction. PATIENTS AND METHODS A single-center retrospective review was performed of patients who underwent orbital wall reconstruction after trauma from 2012 to 2014. Patients were included by admission through the emergency department after facial trauma or by a tertiary referral for post-traumatic orbital deformity. Three-dimensional (3D) computed tomogram-based mirror-imaged reconstruction images of the orbit and an individually manufactured rapid prototype skull model by a 3D printing technique were obtained for each case. Synthetic scaffolds were anatomically pre-molded using the skull model as guide and inserted at the individual orbital defect. Postoperative complications were assessed and 3D volumetric measurements of the orbital cavity were performed. Paired samples t test was used for statistical analysis. RESULTS One hundred four patients with immediate orbital defect reconstructions and 23 post-traumatic orbital deformity reconstructions were included in this study. All reconstructions were successful without immediate postoperative complications, although there were 10 cases with mild enophthalmos and 2 cases with persistent diplopia. Reoperations were performed for 2 cases of persistent diplopia and secondary touchup procedures were performed to contour soft tissue in 4 cases. Postoperative volumetric measurement of the orbital cavity showed nonsignificant volume differences between the damaged orbit and the reconstructed orbit (21.35 ± 1.93 vs 20.93 ± 2.07 cm(2); P = .98). This protocol was extended to severe cases in which more than 40% of the orbital frame was lost and combined with extensive soft tissue defects. CONCLUSION Traumatic orbital reconstruction can be optimized and successful using an individually manufactured rapid prototype skull model and a pre-molded synthetic scaffold by computer-aid design and manufacturing.

Antithrombotic efficacy of an oral low molecular weight heparin conjugated with deoxycholic asset on microsurgical anastomosis in rats

INTRODUCTION Thrombogenic occlusion, at the anastomotic microvessels, contributed impaired blood flow to flap failure. The effect of an orally active low molecular weight heparin (LMWH) derivative conjugated with deoxycholic acid (DOCA) on the patency of anastomosis of the crushed rat artery was investigated, expecting its antithrombogenic effect. MATERIALS AND METHODS 60 Femoral arteries of 30 rats, divided into three groups of 20 each, were reanastomosed. LMWH-DOCA conjugate was orally administered prior to and after operation for 5 consecutive days. On the sixth day of operation, the patency of the anastomosed artery was evaluated. RESULTS The patency of oral LMWH-DOCA (10 mg/kg) group was significantly enhanced from 15% to 45%, compared to non-treated control group. On the other hand, when the dosage of LMWH-DOCA was reduced to 1mg/kg, its efficacy on anastomosis was not as efficacious in terms of patency. The intima of crushed artery was impaired and thrombus formation was examined in the control group. In the drug treated group, the patency was only compromised by a thin layer of thrombus that covered the inner layer of the vessel without causing any damage to the internal elastic lamina. CONCLUSION The medication of oral LMWH-DOCA conjugate has been vetted in microvascular anastomosis of the crushed artery. LMWH-DOCA was potentially useful for improving the patency in compromised vessels after microsurgery.

Changes in graft thickness after skull defect reconstruction with autogenous split calvarial bone graft.

Abstract The ideal material for primary reconstruction of skull defect would be the autogenous bone. However, the long-term evaluation regarding the change in bone graft thickness has not been reported. In this article, we analyzed the thickness changes of the graft according to the time period. Between March 2005 and February 2011, a total of 29 patients underwent skull reconstruction with autogenous split calvarial bone grafts. After applying exclusion criteria, computed tomographic (CT) images of 15 patients were analyzed. The donor bone was harvested in full thickness as 1 piece and then as split. One half of the bone plate was transferred to the defect site; the other half, to the donor site. Both halves were fixed with titanium plates. To compare graft thickness changes, immediate postoperative and follow-up CT scans were analyzed by a single researcher. An anatomic reference was appointed for each patient, and the thickness of the graft on the same level was measured on time-series CT images. Collected data were analyzed with a polynomial random coefficient model. The main causes of the skull defects were trauma and tumor excision. In all cases, the graft thickness was not decreased but even increased in both the donor and recipient sites. The mean graft thicknesses between 6 months and 1 year after the surgery as well as those between 2 and 3 years after the surgery were 1.24-times and 1.56-times thicker than the immediate postoperative thickness, respectively. Graft thickness turned out to be either maintained or increased over time.

Nasal Reconstruction of a Frontonasal Dysplasia Deformity Using Aesthetic Rhinoplasty Techniques

Frontonasal dysplasia (FND) is an unusual congenital condition that presents with a broad range of phenotypes [1]. For this reason, only a small number of cases and the management thereof have been reported in the literature. No consensus has been established regarding the appropriate technique for correcting associated nasal deformities. The clinical picture is highly variable, but the major characteristics include hypertelorism (an increased distance between the eyes), a broad nasal root, a large and bifid nasal tip, and a widows peak [1,2]. Occasional abnormalities include accessory nasal tags, cleft lip, ocular abnormalities (coloboma, cataract, and microphthalmia), conductive hearing loss, basal encephalocele (an opening of the skull with protrusion of the brain), and/or agenesis of the corpus callosum [1,2]. The majority of affected individuals have normal intelligence. The etiology of the condition remains unknown, but seems to be linked to defective embryologic development of the nasal capsule [1,2]. The disorder is thought to be sporadic in most cases [2]. The correction of severe nasal deformities is a valid consideration for FND patients for whom improvement is possible; however, the optimal timing and method for this procedure are still controversial. A boy with non-consanguineous parents and no family history of FND was born by normal spontaneous vaginal delivery. His birth weight was 2.370 kg and the antenatal period was uneventful. On physical examination, the boy was found to have a wide intercanthal distance and a nose deformity characterised by small deformed nostrils and a bifid nose (Fig. 1). Genetic counseling was provided, and the prognosis and appropriate treatment strategies were explained to the parents. Genetic analysis revealed that the patient had a normal ALX3 gene sequence, indicating a sporadic occurrence of FND (Table 1). If the patient desires the exact gene sequence, it is possible to analyze the ALX1 or ALX4 genes, but the parents of the patient did not want to do so in this case. The parents wanted the child to undergo surgical correction as soon as possible to allow for optimal recovery and adaptation. A course of early nasal reconstruction was chosen, and nasal reconstruction based on the principles of aesthetic rhinoplasty was performed at the age of two years and nine months. Fig. 1 Images of a child with features of frontonasal dysplasia, including true ocular hypertelorism, broadening of the nasal root, lack of nasal tip formation, and nose deformity with small nostrils and irregular dorsal skin. Table 1 Mutation details and clinical features of subject with ALX3 mutation The patient presented with mild hypertelorism, a broad nasal root, a large and bifid nasal tip, and a widows peak. Accessory nasal tags, cleft lip, ocular abnormalities, conductive hearing loss, and basal encephalocele were not observed. The major obstacles to restoring the nasal anatomy in this patient included a very short columella, increased alar width, separated lower and upper lateral cartilages, bifid dorsum with severe skin indentation, and a deficient nasal framework. Two strategies were devised to overcome these obstacles. First, the deficient nasal framework was reconstructed by grafting additional cartilages and using appropriate suture techniques. Second, the deficient soft tissue envelope was repositioned on both sides with de-epithelialized bifid nasal soft tissue. First, various aesthetic rhinoplasty techniques were used, including tip extension suture, derotation graft, septal extension graft using conchal cartilages, and interdomal and transdomal sutures. A V-Y patterned transcolumella infracartilagenous incision was performed and the scroll area was subsequently dissected in order to allow lower lateral cartilage mobility, as is done in aesthetic rhinoplasty in East Asian adults (Fig. 2). Dissections were performed along the lower and upper lateral cartilage, which were highly deficient in terms of growth and dimension. In order to reconstruct the lower lateral cartilages, conchal cartilage was harvested from the right ear and attached to the septum, using polydioxanone II (PDS II, Ethicon, Somerville, NJ, USA) 4-0 sutures, in order to function as the septal extension graft. Additionally, we used an AlloDerm (LifeCell, Branchburg, NJ, USA) for dorsal augmentation (1×4 cm in size). The upper lateral cartilage areas were approximated in order to narrow the horizontal nasal width, and a derotation graft of conchal cartilage was fixed with PDS II 4-0 sutures, in order to minimize the cephalic rotation of the nasal tip (Fig. 3). Fig. 2 Preoperative markings. Columellar reconstruction was performed using V-Y advancement of the upper part of the upper lip. Fig. 3 Conchal cartilage was harvested and underdeveloped areas of lower lateral cartilage on both sides were reconstructed. Additional conchal cartilage was used for derotation of the nasal tip. The upper lateral cartilage was approximated for dorsal heightening. ... Second, the widespread dorsal redundant soft tissue was de-epithelialized and moved to the central part of the nose in order to augment the nasal dorsum. Finally, the bifid nasal skin was closed. After six months, the patient underwent scar revision and minor contouring on the nasal dorsum. Fusiform excision was used to remove the previous scar on the nasal dorsum, and undermining and advancement of the skin flap was performed. Multistage craniofacial surgery is justified for FND, and is generally performed at six to eight years of age, resulting in satisfactory cosmetic and functional results [3]. However, a second procedure is often needed, as nose development is completed at the age of 14 years or later [3]. Pham et al. [4] reported three novel cases of frontorhiny that were treated with reconstructive open rhinoplasty, with special attention paid to columellar contouring, eradicating bidifity, columellar lengthening with V-Y closure, and enhancing tip projection The nasal dorsum and underdeveloped nasal tip present unique clinical challenges, and the authors employed a staged definitive rhinoplasty that yielded positive results at a two-year follow-up. Although definitive nasal correction is often performed at older ages, severe nasal deformities have the potential to significantly impact a childs psychological development. This impact leads many parents to request nasal correction as soon as possible. Such a request was the impetus for the early surgery described in this report. In order to correct the nasal deformity of this patient, various aesthetic rhinoplasty techniques were used, such as a V-Y transcolumella incision, derotation graft, tip extension suture, septal extension using conchal cartilage, and interdomal suture techniques [5]. Our strategy proved successful. Although various surgical methods have been developed for nasal correction in patients with FND, the technique presented herein was feasible and satisfactory. The operation resulted in the early improvement of the patients appearance, and no complications occurred (Fig. 4). Although the patient may require future secondary rhinoplasty to enhance the projection of the tip and refine the nose shape, the early correction of the deformed nasal skeleton and soft tissue seems to be beneficial for social adaptation and the development of an improved self-image in growing children. Two years after the surgery, the growth of the nose appeared normal. Fig. 4 Images of the child eight months after the operation.