• Archives of Craniofacial Surgery
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• v.17 no.3
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• pp.103-110
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• 2016

Fractures of frontal sinus account for 5%-12% of all fractures of facial skeleton. Inadequately treated frontal sinus injuries may result in malposition of sinus structures, as well as subsequent distortion of the overlying soft tissue. Such inappropriate treatment can result in aesthetic complaints (contour deformity) as well as medical complications (recurrent sinusitis, mucocele or mucopyocele, osteomyelitis of the frontal bone, meningitis, encephalitis, brain abscess or thrombosis of the cavernous sinus) with potentially fatal outcomes. Frontal contour deformity warrants surgical intervention. Although deformities should be corrected by the deficiency in tissue type, skin and soft tissue correction is considered better choice than bone surgery because of minimal invasiveness. Development of infection in the postoperative period requires all secondary operations to be delayed, pending the resolution of infectious symptoms. The anterior cranial fossa must be isolated from the nasal cavity to prevent infectious complications. Because most of the complications are related to infection, frontal sinus fractures require extensive surgical debridement and adequate restructuring of the anatomy. The authors suggest surgeons to be familiar with various methods of treatment available in the prevention and management of complications following frontal sinus fractures, which is helpful in making the proper decision for secondary frontal sinus fracture surgery.

• Journal of the Optical Society of Korea
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• v.14 no.4
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• pp.431-437
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• 2010

A stack of gradient-index (GRIN) rod lenses cannot be used for coherent anti-Stokes Raman scattering (CARS) microendoscopy for insertion to internal organs through a surgical keyhole with minimal invasiveness. That's because GRIN lens has large amount of inherent chromatic aberrations in spite of absolutely requiring a common focus for pump and Stokes beam with each frequency of ${\omega}_p$ and ${\omega}_S$. For this endoscopic purpose, we need to develop a long slender probe-type objective, namely probe-type microscope objective (PMO). In this paper, we introduce the structure, the working principle, and the design techniques of PMO which is composed of a probe-type lens module (PLM) and an adaptor lens module (ALM). PLM is first designed for a long slender type and ALM is successively designed by using several design parameters from PLM for eliminating optical discords between scanning unit and PLM. A combined module is optimized again to eliminate some coupling disparities between PLM and ALM for the best PMO. As a result, we can obtain a long slender PMO with perfectly diffraction-limited performance for pump beam of 817 nm and Stokes beam of 1064 nm.

• Journal of Korean Neurosurgical Society
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• v.60 no.3
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• pp.301-305
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• 2017

Multiloculated hydrocephalus (MLH) is a condition in which patients have multiple, separate abnormal cerebrospinal fluid collections with no communication between them. Despite technical advancements in pediatric neurosurgery, neurological outcomes are poor in these patients and the approach to this pathology remains problematic especially given individual anatomic complexity and cerebrospinal fluid (CSF) hydrodynamics. A uniform surgical strategy has not yet been developed. Current treatment options for MLH are microsurgical fenestration of separate compartments by open craniotomy or endoscopy, shunt surgery in which multiple catheters are placed in the compartments, and combinations of these modalities. Craniotomy for fenestration allows better visualization of the compartments and membranes, and it can offer easy fenestration or excision of membranes and wide communication of cystic compartments. Hemostasis is more easily achieved. However, because of profound loss of CSF during surgery, open craniotomy is associated with an increased chance of subdural hygroma and/or hematoma collection and shunt malfunction. Endoscopy has advantages such as minimal invasiveness, avoidance of brain retraction, less blood loss, faster operation time, and shorter hospital stay. Disadvantages are also similar to those of open craniotomy. Intraoperative bleeding can usually be easily managed by irrigation or coagulation. However, handling of significant intraoperative bleeding is not as easy. Currently, endoscopic fenestration tends to be performed more often as initial treatment and open craniotomy may be useful in patients requiring repeated endoscopic procedures.

• Clinical Endoscopy
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• v.56 no.5
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• pp.537-545
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• 2023

Achalasia is an esophageal motility disorder characterized by impaired lower esophageal sphincter relaxation and peristalsis of the esophageal body. With the increasing prevalence of achalasia, interest in the role of endoscopy in its diagnosis, treatment, and monitoring is also growing. The major diagnostic modalities for achalasia include high-resolution manometry, esophagogastroduodenoscopy, and barium esophagography. Endoscopic assessment is important for early diagnosis to rule out diseases that mimic achalasia symptoms, such as pseudo-achalasia, esophageal cancer, esophageal webs, and eosinophilic esophagitis. The major endoscopic characteristics suggestive of achalasia include a widened esophageal lumen and food residue in the esophagus. Once diagnosed, achalasia can be treated either endoscopically or surgically. The preference for endoscopic treatment is increasing owing to its minimal invasiveness. Botulinum toxins, pneumatic balloon dilation, and peroral endoscopic myotomy (POEM) are important endoscopic treatments. Previous studies have demonstrated excellent treatment outcomes for POEM, with >95% improvement in dysphagia, making POEM the mainstay treatment option for achalasia. Several studies have reported an increased risk of esophageal cancer in patients with achalasia. However, routine endoscopic surveillance remains controversial owing to the lack of sufficient data. Further studies on surveillance methods and duration are warranted to establish concordant guidelines for the endoscopic surveillance of achalasia.

• Archives of Plastic Surgery
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• v.35 no.3
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• pp.329-332
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• 2008

Purpose: Microcystic adnexal carcinoma is a rare malignant appendage tumor, first described by Goldstein et al in 1982. Here, we present our experience in treatment of a case on the lower lip. Methods: A 52-year-old female with an asymptomatic nodule on the chin, previously misdiagnosed as trichoadenoma by needle aspiration biopsy, was treated by wide excision combined with multiple circumferential frozen biopsies. Results: Pathological examination revealed typical features of microcystic adnexal carcinoma, such as basaloid and squamous cells forming nests and cord-like patterns, horn cysts, and minimal cytologic atypia. The patient has been followed up for 6 months. No sign of recurrence is noted to date. Conclusion: Differentiation from other benign adnexal neoplasms is important for its appropriate treatment. Differentiation can be difficult histologically because it is difficult to acquire an adequate biopsy due to its invasiveness, and clinically due to its asymptomatic and slow growing features. Complete excision is the key treatment, but it may not always be the best solution considering the huge defect that may result and the low incidence of metastasis & deaths owing to the tumor. We add this case to the approximately 300 cases reported worldwide with a review of literature.

• Journal of Korean Neurosurgical Society
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• v.29 no.1
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• pp.87-94
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• 2000

Objective : Various surgical approaches have been implemented to fulfill the ideal goals of treatment for cervical spondylotic lesions. Conventional approaches are represented by anterior approach with or without fusion and posterior approach. The authors has applied newly developed anterior cervical microforaminotomy for these lesions on minimally invasive basis. Materials and Method : Twenty-one patients, with cervical HIVD, or stenosis, or both, underwent anterior cervical microforaminotomy between March, 1998 and April, 1999. Fifteen patients underwent unilateral decompression, and 6 bilateral decompression via unilateral foraminotomy. Operation of one level was performed in 16 patients, 2 levels in 4 patients, and 3 in 1 patient. The foraminotomy was accomplished by resecting the uncovertebral joint. Through this hole, compressed nerve root was decompressed by removing the spondylotic spur or disc fragment, and diagonal removing of posterior osteophyte from foraminotomy site to begining of contralateral nerve root made spinal cord decompression. Results : The outcome was excellent in 17 patients(81%) and good in 4 patients(19%) based on Odom's criteria. No complication was encounterd, and average post-operation hospital stay was 3.7 days. Conclusions : These results indicate that anterior cervical microforaminotomy provide adequate neural decompression, minimum postoperative discomfort and fast recovery.

• Journal of Korean Neurosurgical Society
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• v.54 no.4
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• pp.302-308
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• 2013

Objective : MR perfusion and single photon emission computerized tomography (SPECT) are well known imaging studies to evaluate hemodynamic change between prior to and following superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis in moyamoya disease. But their side effects and invasiveness make discomfort to patients. We evaluated the ivy sign on MR fluid attenuated inversion recovery (FLAIR) images in adult patients with moyamoya disease and compared it with result of SPECT and MR perfusion images. Methods : We enrolled twelve patients (thirteen cases) who were diagnosed with moyamoya disease and underwent STA-MCA anastomosis at our medical institution during a period ranging from September of 2010 to December of 2012. The presence of the ivy sign on MR FLAIR images was classified as Negative (0), Minimal (1), and Positive (2). Regions were classified into four territories: the anterior cerebral artery (ACA), the anterior MCA, the posterior MCA and the posterior cerebral artery. Results : Ivy signs on preoperative and postoperative MR FLAIR were improved (8 and 4 in the ACA regions, 13 and 4 in the anterior MCA regions and 19 and 9 in the posterior MCA regions). Like this result, the cerebrovascular reserve (CVR) on SPECT was significantly increased in the sum of CVR in same regions after STA-MCA anastomosis. Conclusion : After STA-MCA anastomosis, ivy signs were decreased in the cerebral hemisphere. As compared with conventional diagnostic modalities such as SPECT and MR perfusion images, the ivy sign on MR FLAIR is considered as a useful indicator in detecting brain hemodynamic changes between preoperatively and postoperatively in adult moyamoya patients.

• Biomaterials Research
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• v.22 no.4
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• pp.235-248
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• 2018

Background: Injectable hydrogels have been extensively researched for the use as scaffolds or as carriers of therapeutic agents such as drugs, cells, proteins, and bioactive molecules in the treatment of diseases and cancers and the repair and regeneration of tissues. It is because they have the injectability with minimal invasiveness and usability for irregularly shaped sites, in addition to typical advantages of conventional hydrogels such as biocompatibility, permeability to oxygen and nutrient, properties similar to the characteristics of the native extracellular matrix, and porous structure allowing therapeutic agents to be loaded. Main body: In this article, recent studies of injectable hydrogel systems applicable for therapeutic agent delivery, disease/cancer therapy, and tissue engineering have reviewed in terms of the various factors physically and chemically contributing to sol-gel transition via which gels have been formed. The various factors are as follows: several different non-covalent interactions resulting in physical crosslinking (the electrostatic interactions (e.g., the ionic and hydrogen bonds), hydrophobic interactions, ${\pi}$-interactions, and van der Waals forces), in-situ chemical reactions inducing chemical crosslinking (the Diels Alder click reactions, Michael reactions, Schiff base reactions, or enzyme-or photo-mediated reactions), and external stimuli (temperatures, pHs, lights, electric/magnetic fields, ultrasounds, or biomolecular species (e.g., enzyme)). Finally, their applications with accompanying therapeutic agents and notable properties used were reviewed as well. Conclusion: Injectable hydrogels, of which network morphology and properties could be tuned, have shown to control the load and release of therapeutic agents, consequently producing significant therapeutic efficacy. Accordingly, they are believed to be successful and promising biomaterials as scaffolds and carriers of therapeutic agents for disease and cancer therapy and tissue engineering.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.33 no.1
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• pp.1-6
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• 2022

Vocal fold injection (VFI) is widely accepted as a first line treatment in treating unilateral vocal fold paralysis and other vocal fold diseases. Although VFI is advantageous for its minimal invasiveness and efficiency, the invisibility of the needle tip remains an essential handicap in precise localization. Real-time light-guided vocal fold injection (RL-VFI) is a novel technique that was developed under the concept of performing simultaneous injection with precise placement of the needle tip under light guidance. RL-VFI has confirmed its possibility of technical implementation and the feasibility in injecting the needle from various directions through ex vivo animal studies. Further in vivo animal study has approved the safety and feasibility of the procedure when various transcutaneous approaches were applied. Currently, RL-VFI device is authorized for clinical use by the Ministry of Food and Drug Safety in South Korea and is clinically applied to patients with safe and favorable outcome. Several clinical studies are currently under process to approve the safety and the efficiency of RL-VFI. RL-VFI is expected to improve the complication rate and the functional outcome of voice. Furthermore, it will support laryngologists in overcoming the steep learning curve by its intuitive guidance.

• The Journal of the Korean bone and joint tumor society
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• v.10 no.2
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• pp.88-95
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• 2004

Purpose: Current treatment for osteoid osteomas is usually surgical excision of the nidus. Various minimal invasive techniques have been reported to overcome the invasiveness of the surgical excision. We treated 22 patients with osteoid osteoma by percutaneous thermoablation of the nidus under computed-tomography guidance. Materials and Methods: Twenty two consecutive patients underwent CT-guided percutaneous radio-frequency thermoablation between April 1999 and May 2004. The mean age was 26.5(7~55) years. In three cases, the diagnosis was confirmed pathologically before the prodedure while the others clinically and radiologically. Computed tomography (CT)-guided percutaneous RF ablation was performed with general or spinal anesthesia. With an RF electrode, the lesion was heated to 80 or 90 degrees C for 6(3~8) minutes. Clinical success was assessed at a mean of 30(4~62) months after the procedure at out patient clinic or by telephone interview. Results: The procedure was technically successful in all cases except a complication. Patients were discharged on 1.9 days after the procedure and resumed normal activities immediately. All patients but three (86%) remained pain free during follow-up (range 4~62 months). A second thermoablation treatment relieved the recurrent symptoms in 2 patients and the remained had persistent pain without a second prodedure. Conclusion: Percutaneous thermoablation appears to be safe and effective for osteoid osteomas, and is a minimally invasive procedure alternative to surgical resection.