• Journal of International Society for Simulation Surgery
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• v.1 no.1
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• pp.13-15
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• 2014

Nowadays, with advanced 3D printing techniques, the custom-made implant can be manufactured for the patient. Especially in skull reconstruction, it is difficult to design the implant due to complicated geometry. In large defect, an autograft is inappropriate to cover the defect due to donor morbidity. We present the process of manufacturing the 3D custom-made implant for skull reconstruction. There was one patient with skull defect repaired using custom-made 3D titanium implant in the plastic and reconstructive surgery department. The patient had defect of the left parieto-temporal area after craniectomy due to traumatic subdural hematoma. Custom-made 3D titanium implants were manufactured by Medyssey Co., Ltd. using 3D CT data, Mimics software and an EBM (Electron Beam Melting) machine. The engineer and surgeon reviewed several different designs and simulated a mock surgery on 3D skull model. During the operation, the custom-made implant was fit to the defect properly without dead space. The operative site healed without any specific complications. In skull reconstruction, autograft has been the treatment of choice. However, it is not always available and depends on the size of defect and donor morbidity. As 3D printing technique has been advanced, it is useful to manufacture custom-made implant for skull reconstruction.

• Journal of Korean Neurosurgical Society
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• v.42 no.2
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• pp.89-91
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• 2007

Objective : Cranioplasty is necessary to repair the cranial defect, produced either by decompressive craniectomy or removal of the contaminated depressed skull fracture. Complications are relatively common after cranioplasty, being reported up to 23.6%. We examined the incidence and risk factors of infectious complications after cranioplasty during last 6 year period. Methods : From January 2000 to December 2005, 107 cranioplasties were performed in our institution. The infectious complications occurred in 17 cases that required the removal of the bone flap. We examined the age of the patients, causes of the skull defect, timing of the cranioplasty the size of the defect, and kinds of the cranioplasty material. The size of the skull defect was calculated by a formula, $3.14{\times}long\;axis\;{\times}short$ axis. The cranioplasty material was autogenous bone kept in a freezer in 74 patients, and polymethylmetacrylate in 33 patients. Statistical significance was tested using the chi-square test. Results : The infection occurred in 17 patients in 107 cranioplasties (15.9%). It occurred in 2 of 29 cases of less than $75\;cm^2$ defect (6.9%), and 6 in 54 cases of $75{\sim}125\;cm^2$ defect (11.1%). Also, it occurred in 9 of 24 cases of more than $125\;cm^2$ defect (37.5%). This difference was statistically significant (p <0.01). Conclusion : During the cranioplasty, special attention is required when the skull defect is large since the infection tends to occurr more commonly.

• Journal of Korean Neurosurgical Society
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• v.56 no.5
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• pp.410-418
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• 2014

Objective : The epidural fluid collection (EFC) as a complication of cranioplasty is not well-described in the literature. This study aimed to identify the predictive factors for the development of EFC as a complication of cranioplasty, and its outcomes. Methods : From January 2004 to December 2012, 117 cranioplasty were performed in our institution. One-hundred-and-six of these patients were classified as either having EFC, or not having EFC. The two groups were compared to identify risk factors for EFC. Statistical significance was tested using the t-test and chi-square test, and a logistic regression analysis. Results : Of the 117 patients undergoing cranioplasty, 59 (50.4%) suffered complications, and EFC occurred in 48 of the patients (41.0%). In the t-test and chi-test, risk factors for EFC were size of the skull defect (p=0.003) and postoperative air bubbles in the epidural space (p<0.001). In a logistic regression, the only statistically significant factor associated with development of EFC was the presence of postoperative air bubbles. The EFC disappeared or regressed over time in 30 of the 48 patients (62.5%), as shown by follow-up brain computed tomographic scan, but 17 patients (35.4%) required reoperation. Conclusion : EFC after cranioplasty is predicted by postoperative air bubbles in the epidural space. Most EFC can be treated conservatively. However, reoperation is necessary to resolve about a third of the cases. During cranioplasty, special attention is required when the skull defect is large, since EFC is then more likely.

• Archives of Craniofacial Surgery
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• v.16 no.1
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• pp.11-16
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• 2015

Background: Source material used to fill calvarial defects includes autologous bones and synthetic alternatives. While autologous bone is preferable to synthetic material, autologous reconstruction is not always feasible due to defect size, unacceptable donor-site morbidity, and other issues. Today, advanced three-dimensional (3D) printing techniques allow for fabrication of titanium implants customized to the exact need of individual patients with calvarial defects. In this report, we present three cases of calvarial reconstructions using 3D-printed porous titanium implants. Methods: From 2013 through 2014, three calvarial defects were repaired using custom-made 3D porous titanium implants. The defects were due either to traumatic subdural hematoma or to meningioma and were located in parieto-occipital, fronto-temporo-parietal, and parieto-temporal areas. The implants were prepared using individual 3D computed tomography (CT) data, Mimics software, and an electron beam melting machine. For each patient, several designs of the implant were evaluated against 3D-printed skull models. All three cases had a custom-made 3D porous titanium implant laid on the defect and rigid fixation was done with 8 mm screws. Results: The custom-made 3D implants fit each patient's skull defect precisely without any dead space. The operative site healed without any specific complications. Postoperative CTs revealed the implants to be in correct position. Conclusion: An autologous graft is not a feasible option in the reconstruction of large calvarial defects. Ideally, synthetic materials for calvarial reconstruction should be easily applicable, durable, and strong. In these aspects, a 3D titanium implant can be an optimal source material in calvarial reconstruction.

• Archives of Plastic Surgery
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• v.39 no.2
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• pp.118-123
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• 2012

Background : An area of the skull exposed by burn injury has been covered by various methods including local flap, skin graft, or free flap surgery. Each method has disadvantages, such as postoperative alopecia or donor site morbidities. Due to the risk of osteomyelitis in the injured skull during the expansion period, tissue expansion was excluded from primary reconstruction. However, successful primary reconstruction was possible in burned skull by tissue expansion. Methods : From January 2000 to 2011, tissue expansion surgery was performed on 10 patients who had sustained electrical burn injuries. In the 3 initial cases, removal of the injured part of the skull and a bone graft was performed. In the latter 7 cases, the injured skull tissue was preserved and covered with a scalp flap directly to obtain natural bone healing and bone remodeling. Results : The mean age of patients was $49.9{\pm}12.2$ years, with 8 male and 2 female. The size of the burn wound was an average of $119.6{\pm}36.7cm^2$. The mean expansion duration was $65.5{\pm}5.6$ days, and the inflation volume was an average of $615{\pm}197.6mL$. Mean defect size was $122.2{\pm}34.9cm^2$. The complications including infection, hematoma, and the exposure of the expander were observed in 4 cases. Nonetheless, only 1 case required revision. Conclusions : Successful coverage was performed by tissue expansion surgery in burned skull primarily and no secondary reconstruction was needed. Although the risks of osteomyelitis during the expansion period were present, constant coverage of the injured skull and active wound treatment helped successful primary reconstruction of burned skull by tissue expansion.

• Journal of Rhinology
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• v.25 no.2
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• pp.123-129
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• 2018

Background and Objectives: Endoscopic repair of cerebrospinal fluid (CSF) leak can avoid morbidity of open approaches and has shown a favorable success rate. Free mucosal graft is a good method, and multi-layered repair is more favorable. The inferior turbinate has been commonly utilized for the free mucosal graft, but we newly designed it as a bone-periosteal-mucosal composite graft for multilayered reconstruction. Subjects and Method: Four subjects with a skull base defect were treated with this method. The inferior turbinate was partially resected including the conchal bone and was trimmed according to defect size. Both bony parts and periosteum were preserved on the basolateral side of the mucosa as a composite graft. The graft was applied to the defect site using an overlay technique. Results: All cases were successfully repaired without any complications. Three of them had a defect size greater than 10-12 mm, and the graft stably repaired the CSF leakage. Conclusion: Endoscopic repair of CSF leakage using inferior turbinate composite graft is a simple and easy method and would be favorable for defect sizes greater than 10 mm.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.4
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• pp.256-263
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• 2002

Using the rat's skull, the study on the biodegradability and guided bone regeneration of the chitosan membrane was performed. The results are as follows: 1. The biodegradability of the chitosan membrane could not be confirmed, but after 12 weeks, this membrane did not yet break into small pieces and there was no specific local tissue reaction. 2. It was not certain whether the pore size of this membrane was affected on osteoblastic activity. 3. After 6 weeks, the bony defect area of rat's skull was not completely filled, but on high magnification it showed that the osteoclasts and the osteoblasts were observed in the regenerating area. In conclusion, the chitosan membrane developed in this study was fit for guided bone regeneration.

• Journal of Embryo Transfer
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• v.32 no.1
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• pp.33-38
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• 2017

A 10-day-old, Holstein calf with facial mass of 10 cm in diameter at the forehead region referred to Veterinary Medical Teaching Hospital in Chungnam National University. The mass was soft and fluctuating swelling. It had normal skin and hair hanging forward from frontal region and was thought to contain cerebrospinal fluid. On the skull radiography, cauliflower like-irregular marginated, soft tissue opacity mass was identified craniodorsal to the frontal bone. The mass appeared as a cyst filled with anechoic fluid on ultrasonography. Soft tissue structures considered brain tissues were observed in the deep area of the mass. On the computed tomography, a large skull defect of left side frontal bone was found, and heterogeneous materials were exposed through the defect but exposure of cerebral meninges and brain tissue were not confirmative. On magnetic resonance imaging, herniated left brain parenchyma showed heterogenous T2 and T1 hyperinsensity. In the intracranium, T2 hyperinstense and T1 hypointense fluid was identified on the left side, instead of left cerebral parenchyma. Also leftward shift of right hemisphere and midline structure, including thalamus and midbrain, were observed. The definitive diagnosis was confirmed as a meningoencephalocele based on computed tomography and magnetic resonance imaging. The calf was euthanized and necropsy was performed. On necropsy, both hemisphere were developed unequally with different size. One side hemisphere was grown in the outside through 10 cm hole on the median plane.

• Archives of Plastic Surgery
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• v.49 no.2
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• pp.174-183
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• 2022

Management of traumatic skull base fractures and associated complications pose a unique reconstructive challenge. The goals of skull base reconstruction include structural support for the brain and orbit, separation of the central nervous system from the aerodigestive tract, volume to decrease dead space, and restoration of the three-dimensional appearance of the face and cranium with bone and soft tissues. An open bicoronal approach is the most commonly used technique for craniofacial disassembly of the bifrontal region, with evacuation of intracranial hemorrhage and dural repair performed prior to reconstruction. Depending on the defect size and underlying patient and operative factors, reconstruction may involve bony reconstruction using autografts, allografts, or prosthetics in addition to soft tissue reconstruction using vascularized local or distant tissues. The vast majority of traumatic anterior cranial fossa (ACF) injuries resulting in smaller defects of the cranial base itself can be successfully reconstructed using local pedicled pericranial or galeal flaps. Compared with historical nonvascularized ACF reconstructive options, vascularized reconstruction using pericranial and/or galeal flaps has decreased the rate of cerebrospinal fluid (CSF) leak from 25 to 6.5%. We review the existing literature on this uncommon entity and present our case series of n = 6 patients undergoing traumatic reconstruction of the ACF at an urban Level 1 trauma center from 2016 to 2018. There were no postoperative CSF leaks, mucoceles, episodes of meningitis, or deaths during the study follow-up period. In conclusion, use of pericranial, galeal, and free flaps, as indicated, can provide reliable and durable reconstruction of a wide variety of injuries.

• Archives of Craniofacial Surgery
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• v.14 no.1
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• pp.69-72
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• 2013

Lateral eyebrow mass with primary skull lesion are rare in pediatric population. Although epidermoid cyst and dermoid cyst are the most commonly encountered skull lesions in pediatric population, Langerhans cell histiocytosis (LCH) is rarely reported. We report a case of LCH arising from the lateral eyebrow with osteolytic lesion involving the frontal bone. A 5-year-old boy was presented with a hard, fixed mass in his lateral eyebrow. Contrast magnetic resonance imaging revealed inhomogeneous enhancement of the mass with direct invasion of the frontal bone and adjacent dura mater. Under general anesthesia, linear incision at the lateral eyebrow region was made. Intraoperative evaluation revealed hard, fixed and well-defined soft tissue mass. The final extirpated mass was $2.5{\times}2.4cm$ in size, and was accompanied by a $1{\times}1cm$ sized defect on the frontal bone with intact dura mater. The surgical wound was closed primarily by a layer-by-layer fashion. Histologic examination was later performed for definite diagnosis. The histologic examination revealed abnormal proliferation of Langerhans cell with granuloma formation. Radionuclide bone scan and positron emission tomography was taken and revealed free of multi-organ involvement. At 3 months after surgery, natural looking contour at the lateral eyebrow region was observed with no tumor recurrence. Differential diagnosis of the hard and fixed mass at the lateral eyebrow region affecting the primary skull lesion from pediatric population includes epidermoid cyst, dermoid cyst and LCH. Generally, brief physical examination with plain X-ray view can be performed for clinical evaluation, but for a definite diagnosis, contrast MRI may be helpful.