• Journal of Korean Neurosurgical Society
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• v.41 no.5
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• pp.343-346
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• 2007

Hypoplasia of the internal carotid artery is a rare congenital anomaly. Agenesis, aplasia, and hypoplasia of the internal carotid artery [ICA] are frequently associated with cerebral aneurysms in the circle of Willis. Authors report two cases with congenital hypoplasia of the ICA accompanying with the aneurysms. Transfemoral cerebral angiography [TFCA] in one patient identified nonvisualization of the left ICA. Bilateral anterior cerebral artery [ACA] and middle cerebral artery [MCA] were supplied from the right ICA accompanying with two aneurysms at anterior communicating artery [AcoA] and A1 portion of the left ACA. TFCA in another patient demonstrated hypoplastic left ICA and left ACA filled from the right ICA accompanying with AcoA aneurysm. Left MCA was filled from basilar artery via posterior communicating artery [PcoA]. Skull base computed tomography [CT] in two patients showed hypoplastic carotid canal. Authors performed direct aneurysmal neck clipping. Follow up CT angiography [CTA] at one year after surgery did not show regrowth or new development of the aneurysm. In patients with hypoplastic ICA, neurosurgeons should be aware of the possibility of development of the aneurysms, presumably because of hemodynamic process. Direct aneurysmal neck clipping is a good treatment modality. After operation, regular CTA, magnetic resonance angiography [MRA] or TFCA is needed to find progressive lesion and to prevent cerebrovascular attack [CVA].

• Imaging Science in Dentistry
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• v.50 no.4
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• pp.323-330
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• 2020

Purpose: The mastoid region is ideal for studying sexual dimorphism due to its anatomical position at the base of the skull. This study aimed to determine sex in the Iranian population based on measurements of the mastoid process using different data mining algorithms. Materials and Methods: This retrospective study was conducted on 190 3-dimensional cone-beam computed tomographic (CBCT) images of 105 women and 85 men between the ages of 18 and 70 years. On each CBCT scan, the following 9 landmarks were measured: the distance between the porion and the mastoidale; the mastoid length, height, and width; the distance between the mastoidale and the mastoid incision; the intermastoid distance (IMD); the distance between the lowest point of the mastoid triangle and the most prominent convex surface of the mastoid (MF); the distance between the most prominent convex mastoid point (IMSLD); and the intersecting angle drawn from the most prominent right and left mastoid point (MMCA). Several predictive models were constructed and their accuracy was compared using cross-validation. Results: The results of the t-test revealed a statistically significant difference between the sexes in all variables except MF and MMCA. The random forest model, with an accuracy of 97.0%, had the best performance in predicting sex. The IMSLD and IMD made the largest contributions to predicting sex, while the MMCA variable had the least significant role. Conclusion: These results show the possibility of developing an accurate tool using data mining algorithms for sex determination in the forensic framework.

• The Research Journal of the Costume Culture
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• v.20 no.5
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• pp.709-724
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• 2012

This study examined the characteristics of costumes worn at Halloween parties, a form of cultural entertainment commonly seen in the U.S. The Halloween party culture involves children and adolescents wearing costumes, decorating their bodies, and mimicking famous characters. Furthermore, the types and motifs of Halloween costumes have become a means of expressing individuality. This study conducted empirical research on how such motifs were reflected in modern Halloween party-wear in order to provide basic data regarding the development and design of Halloween costumes and the formation of the related entertainment culture. This study researched the shape of costumes and the type of traditional motif presented in these costumes, as well as analyzed the symbolic meaning of each motif. The research process was as follows. First, this study investigated the origin and evolution of Halloween by researching precedent studies, books, and internet data. Second, this study extracted the types of traditional Halloween motifs by analyzing the characteristics and symbols of Halloween costumes commonly presented in such materials. After collecting 547 Halloween-related images from U.S. and Korean Internet websites, this study sorted and analyzed images that could represent traditional Halloween motifs. According to the results, representative traditional Halloween motifs included black cats, white rabbits, tridents, scarecrows, skull and bones, ghosts, witches, vampires, bats, werewolves, and jack-o-lanterns(pumpkins, etc.). The sentiments for such traditional Halloween motifs changed according to era and race. The symbolic meaning would continuously change - from positive to negative and vice versa - to reflect various socio-cultural phenomena. The results of this study are expected to be used as basic data for developing Halloween costume designs and the related entertainment culture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.3621-3625
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• 2010

Colored cubic-zirconia specimens made by skull melt process were annealed in vacuum at the temperature of $1200^{\circ}{\sim}1400^{\circ}C$ for 10~60 minutes to enhance the color. The three different colored specimens become darker and eventually are black as annealing temperature and time increase. Conventional gem stone grading method and XPS were employed to quantify the property change and to reveal the mechanism of the color change. Color was changed apparently but the hardness and apparent density did not vary with annealing. Based on XPS result, we concluded that the main cause of the color change in cubic zirconia might be the change of Y-O bonding energy state of $Y2_O_3$ phase-stabilizer by vacuum annealing.

• Journal of Oral Medicine and Pain
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• v.16 no.1
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• pp.33-72
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• 1991

The purpose of this study was to investigate the stress distribution and the displacement in the temporomandibular joints following the teeth loss patterns. The three dimensional finite element method was used for a mathematical model. The finite element model was composed of 1,632 elements and 2,411 nodes in the mandible with articular disc and mandibular fossa of the temporal bone. The masseter, the temporal and the internal pterygoid muscle forces were applied at each insertion site, bisecting point of gonion and antegonion, tip of the coronoid process, and gonion at the ration of 2:2:1 respectively. The directions of muscles force were obtained from frontal and lateral cephalometric tracings using bony landmarks of the skull. The results were as follows : 1. In control model, the minimum principal stresses were concentrated on the region of anterosuperior part of the condyle head and articular disc, and maximum principal stresses on the anterior part of the condyle head and posterolateral part of the articular disc. 2. In case of unilateral teeth loss, the greater principal stress appeared at the teeth loss side and the principal stresses increased at the teeth loss side as the number of the posterior teeth loss went up. 3. In case of bilateral teeth loss, the principal stresses were greater than those of the control model and as the number of the posterior teeth loss increased, the grater principal stresses on the temporomandibular joints appeared at the both side. 4. When the posterior teeth existed bilateral, the principal stress patterns were similar to those of the control model. 5. The displacement ws directed mainly upward and backward in the upper part of the temporomandibular joints and upward and forward in the largest part of the condyle head. The displacement increased as the number of the posterior teeth loss went up.

• Journal of radiological science and technology
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• v.22 no.2
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• pp.27-32
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• 1999

Cochlear implant poses a contraindication to the magnetic resonance imaging(MRI) process, because MRI generates artifacts, inducing an electrical current and causing device magnetization. CT is relatively expensive and the metal electrodes scatter the image. Post-implantation radiological studies using anterior-posterior transorbital, submental-vertex and lateral views, the intracochlear electrodes are not well displayed. Therefore, the authors developed a special view, which we call the cochlear view. The patient is sitting in front of a vertical device. Then the midsagittal plane is adjusted to form an angle of $15^{\circ},\;30^{\circ}$, and $45^{\circ}$ with the film. The flexion of the neck is adjusted to make the infraorbitomeatal line(IOML) is parallel with the transverse axis of the film. The central ray is directed to exit from the skull at point which is 3.0 cm anterior and 2.0 cm superior to the EAM(external auditory meatus). Results have shown that single radiography of the cochlear view provides sufficient information to demonstrate the position of the electrodes array and the depth of insertion in cochlear. Radiography of the cochlear view in angle of $45^{\circ}$ is an excellent image. The cochlear view gives the greatest amount of medical information with the least radiation and lowest medical cost. It can be widely used in all cochlear implant clinics.

• The korean journal of orthodontics
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• v.48 no.2
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• pp.81-89
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• 2018

Objective: The aim of this study was to evaluate the stress distribution and displacement of various craniofacial structures after nonsurgical rapid palatal expansion (RPE) with conventional (C-RPE), bone-borne (B-RPE), and miniscrew-assisted (MARPE) expanders for young adults using three-dimensional finite element analysis (3D FEA). Methods: Conventional, bone-borne, and miniscrew-assisted palatal expanders were designed to simulate expansion in a 3D FE model created from a 20-year-old human dry skull. Stress distribution and the displacement pattern for each circumaxillary suture and anchor tooth were calculated. Results: The results showed that C-RPE induced the greatest stress along the frontal process of the maxilla and around the anchor teeth, followed by the suture area, whereas B-RPE generated the greatest stress around the miniscrew, although the area was limited within the suture. Compared with the other appliances, MARPE caused relatively even stress distribution, decreased the stress on the buccal plate of the anchor teeth, and reduced tipping of the anchor teeth. Conclusions: The findings of this study suggest that the incorporation of miniscrews in RPE devices may contribute to force delivery to the sutures and a decrease in excessive stress on the buccal plate. Thus, MARPE may serve as an effective modality for the nonsurgical treatment of transverse maxillary deficiency in young adults.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.21 no.1
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• pp.99-107
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• 1991

The purpose of this study was to decide the proper projection angle that could avoid the superimposition of the petrous portion of temporal bone and posterior clinoid process in cephalometric lateral and basal view of the 10 dry skulls and to analyze the reproducibility of a modified Accurad-100 head holder device from Denar Co. and a cephalostat head holder in 30 transcranial radiographs of the dry skull. The results were obtained as follows: The vertical angle was 24.5±4.1° and the horizontal angle was 3.0 ±5.7°. The distances between arbitrary 3 points which were on the TMJ area were as follows: AB 16.76±0.27㎜, BC 8.79±0.18㎜ in the transcranial radiographs using modified Accurad-100 head holder, AB 29.03±0.14㎜, AC 19.95±0.24㎜, BC 10.08±0.07㎜ in the transcranial radiographs using cephalostat.

• Journal of Yeungnam Medical Science
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• v.2 no.1
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• pp.259-264
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• 1985

Neuroblastoma is the most common extracranial solid tumor of childhood which presents various clinical symptoms depending on the primary and metastatic sites. However, it has been rarely reported that sudden onset of blindness was the chief complaint of neuroblastoma. A four years old boy was admitted to the Yeungnam University Hospital with the chief complaint of a sudden onset of blindness due to a distant metastasis of abdominal neuroblastoma to the sphenoid sinus. On admission, both side pupils were dilated without light reflex, fundoscopy showed pale optic disk, electroretinogram was subnormal and visual evoked potential showed no response. The liver was palpable in $3{\frac{1}{2}}$ finger breadth from the right costal margin and adult fist sized mass was palpable in the right flank. Skull X-ray showed destructed sphenoid bone and clinoid process and brain CT scan showed tumor mass in the sphenoid sinus and left orbit. Ultrasonogram and CT scan of the abdomen showed large tumor masses around the right kidney and para-aortic and retropancreatic lymph node. IVP showed displaced right calyceal system with preserved contour. Left supraclavicular lymph node which appeared after admission was biopsied and it showed poorly differentiated neuroblasts. He was treated according to the multiagent chemotherapy schedule for stage IV neuroblastoma patient of children's cancer study group. Abdominal tumor masses and sphenoid sinus mass were markedly reduced after 2 courses of the combination chemotherapy of cyclophosphamide, vincristine, DTIC, adriamycin and VM-26. Eventhough the blindness was not improved, the patient has been in good clinical condition.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.5
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• pp.567-571
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• 2007

Lateral pharyngeal space is one of potential fascial planes of head and neck, that may become involved by various pathological processes, such as infection, inflammation and neoplasm. The calcified stylohyoid ligament with styloid process is also located in this space, so this space is more acquainted with Eagle's syndrome in oral and maxillofacial field. During the mandibular transbuccal fixation procedures of 29-year old female patient who had right condylar neck and left parasymphysis fracture, we had lost one 10.0 mm miniscrew. After confirming the location of the lost miniscrew from different angled plain skull radiographies, we tried to find it in the lateral pharyngeal space via transtonsillar approach at the time of plate removal operation. This case report is aimed to share our valuable experience of the effective approach way to the lateral pharyngeal space, which has many advantages, such as short operative time, minimal bleeding, fast post-operative recovery, and less morbidity. The related literature is also reviewed.