• Imaging Science in Dentistry
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• v.43 no.2
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• pp.105-109
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• 2013

Purpose: Preoperative radiographic assessment of the mandibular third molars is essential to prevent inferior alveolar nerve damage during extraction. The purpose of this study was to assess the reliability of panoramic signs of association between the roots of teeth and the canal, and to compare the panoramic signs with cone beam computed tomography (CBCT) findings. Materials and Methods: CBCT images of 132 impacted mandibular third molars were evaluated to determine the association of the root to the canal. The CBCT findings were compared with the corresponding panoramic images. Logistic regression analysis was used to define the diagnostic criteria of the panoramic images. Results: Among the panoramic signs, loss of the cortical line was the most frequent radiographic sign predicting association (sensitivity: 79.31). Contact of the tooth with the canal was observed in all cases in which the loss of cortical line of the canal or darkening of the roots was found on the panoramic radiographs. Conclusion: Darkening of the roots and loss of the cortical line on panoramic radiographs might be highly suggestive of the risk of nerve injury.

• Phonetics and Speech Sciences
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• v.4 no.3
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• pp.179-186
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• 2012

The aims of this study are to consider auditory physiological characteristics and to confirm audiological evaluation and interpretation in regards to cases of sensorineural hearing loss that observe an abnormal AB gap. Vestibulosaccular hearing occurs when there is an abnormally large air-bone gap (AB gap) in sensorineural hearing loss, also known as pure cochlear conductive hearing loss. Generally, an AB gap is caused by damage to the external and/or middle ear. In conductive hearing loss, loss of air condition hearing occurs due to a loss of resonance in the outer ear and/or impedance mismatching in the middle ear. Most of these types of hearing loss can be treated medically and surgically. However, there is no medical treatment for an AB gap in sensorineural hearing loss and hearing loss can worsen gradually or suddenly. In addition, many studies have reported that head trauma makes hearing loss even more serious. Therefore, in order to differentiate between conductive hearing losses, it is important to check whether or not there is an enlarged vestibular aqueduct by means of temporal bone computerized tomography and/or magnetic resonance imaging.

• Imaging Science in Dentistry
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• v.45 no.2
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• pp.103-108
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• 2015

Bony fusion between the mandibular condyle and skull base involves temporomandibular joint (TMJ) bony ankylosis. This condition might originate from trauma, infection, or systemic disease. TMJ adhesion can develop after synovial damage. Both TMJ ankylosis and adhesion lead to functional impairment and pain. Here, we present a case of a 50-year-old female who had bony ankylosis of the right TMJ and adhesion of the left TMJ. She had otitis media in the right ear. A large mass in the right TMJ was observed on computed tomograph. Magnetic resonance image showed a large fused bone mass with normal bone marrow in the right TMJ and flattening of the condyle with a thin disk in the left TMJ. Gap arthroplasty with temporal fascia was performed on the right TMJ, and discectomy, high condylectomy, and coronoidectomy were performed on the left TMJ. During a 2-year follow-up after surgery, the patient had no recurrence.

• Imaging Science in Dentistry
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• v.47 no.1
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• pp.63-68
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• 2017

Some complications can arise with the usage of local anesthesia for dental procedures, including the fracture of needles in the patient. This is a rare incident, usually caused by the patient's sudden movements during anesthetic block. Its complications are not common, but can include pain, trismus, inflammation in the region, difficulty in swallowing, and migration of the object, which is the least common but has the ability to cause more serious damage to the patient. This report describes a case in which, after the fracture of the anesthetic needle used during alveolar nerve block for exodontia of the left mandibular third molar, the fragment moved significantly in the first 2 months, before stabilizing after the third month of radiographic monitoring.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.22 no.1
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• pp.130-135
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• 2014

FOD(Foreign Object Debris) has the potential threat to damage aircraft during critical phases of take-off and landing roll with some objects including metal on the runway. FOD can be found anywhere on an airport's air operation areas such as runway, taxiway and apron. It can lead to catastrophic loss of life and airframe, and increased maintenance and operating costs. In this paper, we defined FOD and surveyed its riskiness and necessity of automatic FOD detection system. We compared the requirements of the environment in Korea to the FAA advisory circular. Also we analyzed operation methods of FOD detection systems already installed at some airports. Based on the surveys mentioned above, we propose hybrid type of FOD detection system considering the environment in Korea which uses millimeter wave radar, optical camera and thermal imaging camera to detect FOD efficiently. In management approach, fixed type of the system should be installed for real-time monitoring, and mobile type of the system can be used additionally.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.436-442
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• 2009

Tomography images reconstructed from conebeam CT make it possible to observe inside of the projected object without any damage, and so it has been widely used in the industrial and medical fields. Recent advanced imaging equipment can produce high-resolution CT images. However, it takes much time to reconstruct the obtained large dataset. To reduce the time to reconstruct CT images, we propose an accelerating method using GPU (graphics processing unit). Reconstruction consists of mainly two parts, filtering and back-projection. In filtering phase, we applied 4ch image compression method and in back-projection phase, computation reduction method using depth test is applied. The experimental results show that the proposed method accelerates the speed 50 times than the CPU-based program optimized with OpenMP by utilizing the high-computing power of parallelized GPU.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.6
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• pp.989-995
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• 2013

Unlike fossil-or nuclear fuel-based power generation, wind power generation using inexhaustible wind energy is a pollution-free, hazardless power generation method. In this study, ultrasound thermography is used for fabricating specimens of wind power generator bearings and wind power generator supplement flanges, and an optimally designed ultrasound horn and ultrasound excitation system are used for detecting damage to part materials of a wind power generation setup. In addition, thermal flow analysis and ultrasonic thermography imaging are comparatively analyzed for improving the detection reliability in terms of surface and internal defects of part materials and for verifying the developed system's field applicability and reliability.

• The Korean Journal of Pain
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• v.31 no.1
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• pp.54-57
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• 2018

Burner or stinger syndrome is a rare sports injury caused by direct or indirect trauma during high-speed or contact sports mainly in young athletes. It affects peripheral nerves, plexus trunks or spinal nerve roots, causing paralysis, paresthesia and pain. We report the case of a 57-year-old male athlete suffering from burner syndrome related to a lumbar nerve root. He presented with prolonged pain and partial paralysis of the right leg after a skewed landing during the long jump. He was initially misdiagnosed since the first magnet resonance imaging was normal whereas electromyography showed denervation. The insurance company refused to pay damage claims. Partial recovery was achieved by pain medication and physiotherapy. Burner syndrome is an injury of physically active individuals of any age and may appear in the cervical and lumbar area. MRI may be normal due to the lack of complete nerve transection, but electromyography typically shows pathologic results.

• Clinics in Shoulder and Elbow
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• v.23 no.1
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• pp.37-40
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• 2020

Heterotopic ossification is formation of bone in atypical extra-skeletal tissues and usually occurs spontaneously or following neurologic injury with unknown cause. We report a 46-year-old female with right shoulder pain and restricted range of motion (ROM) for 3 months without history of trauma. Magnetic resonance imaging (MRI) showed a lesion within the rotator cuff supraglenoid. Excisional biopsy from a previous institution revealed a heterotopic ossificans (HO). Following repeat MRI and bone scan, histopathology from arthroscopic resection confirmed an HO. The patient demonstrated improved pain and ROM at follow-up. Idiopathic HO rarely occurs in the shoulder joint, and resection of HO should be delayed until maturation of the lesion to avoid recurrence. The current case showed that arthroscopic HO resection provides an excellent surgical view to ensure complete lesion removal and minimize soft tissue damage at the supraglenoid area. Furthermore, the minimally invasive procedure of arthroscopy may reduce rehabilitation time and facilitate early return to work.

• Journal of Korean Neurosurgical Society
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• v.40 no.2
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• pp.117-121
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• 2006

The surgical removal of solid deep-seated hemangioblastomas remains challenging, because treatment of these lesions is often complicated by severe bleeding associated with the rich vascularity of this tumor, and by severe neural tissue injury associated with the difficulty of en bloc resection, especially when the tumor is located at the cervicomedullary junction. Therefore, preoperative embolization of deep-seated solid hemangioblastomas may play an important role in successful surgical removal by reducing major bleeding and neural tissue damage. A 24-year-old woman, 28-weeks pregnant, was admitted to our hospital for the evaluation of quadriparesis, and brain magnetic resonance imaging[MRI] revealed intra-axial mass lesion in the cervicomedullary junction. After delivery, her neurologic symptoms became aggravated, and we decided to operate. Preoperative angiography revealed a hypervascular tumor in the posterior fossa, and embolization of the main feeding artery using gelfoam and microcoil, resulted in marked reduction of tumor vascularity. She underwent a midline suboccipital craniotomy involving the removal of the arch of C-1. The tumor was totally removed through a midline myelotomy, and at her 6-month follow-up she walked independently. We report on the combined use of the preoperative embolization of feeding vessels and subsequent operative resection in a patient with a solid hemangioblastoma at the cervicomedullary junction immediately after delivery.