• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.27 no.2
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• pp.117-125
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• 1997

The purpose of this study was to evaluate the detectability of various radiographic techniques for mandibular condylar lesions. Erosive lesion, osteophyte and flattening were formed on the artificial mandibular condyle, and panoramic, transcranial, transorbital radiography, lateral and frontal tomography were taken. The results were as follows; 1. The detectability for erosive lesions was superior in the order of frontal tomography(96％), lateral tomography(78％), transorbital(59％), transcranial(16％) and panoramic(48％) radiography. 2. The location of erosive lesion that showed the highest detectability was the medial third in panoramic, the lateral third in transcranial, the central portion of anteroposterior direction in transorbital, the central portion of mediolateral direction and the posterior third in lateral tomography. Frontal tomography disclosed all erosive lesions except one anterolateral lesion. 3. The detectability of osteophyte was 100％ in lateral tomography, 78％ in transcranial and 56％ in panoramic radiography. 4. For flattening, lateral tomography showed the flattened condyle, but both panoramic and transcranial views showed only decreased bone density without the change of condylar shape.

• Korean Journal of Head & Neck Oncology
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• v.29 no.2
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• pp.37-40
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• 2013

Background and Objectives : To assess the usefulness of computed tomography image before papillary thyroid cancer surgery, focus on confirmation of lateral cervical lymph node metastasis not detected by ultrasonography. Material and Methods : From January 2008 to May 2009, total 150 patients who had undergone thyroid surgery and been confirmed papillary thyroid cancer pathologically were enrolled. They had taken neck computed tomography following the ultrasonography. Results : Computed tomography had found suspicious metastatic lateral neck lesion in 13 patients. After the image study, lateral neck lymph node dissection had been included in their surgical plan. Of these, only 7 cases were confirmed pathologically lateral neck lymph node metastasis(positive predictive value=0.54). Taken as whole 150 patients, additionally 4.7% of patients confirmed lateral neck lymph node metastasis by preoperative computed tomography. Conclusion : If preoperative ultrasonography was performed precisely, additional benefits that could be achieved by computed tomography were not much.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.3
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• pp.285-292
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• 2011

The purpose of thise study was to measure the thickness of the sinus lateral wall using computed tomography (CT), and to find the most suitable vertical position for lateral window opening prior to sinus elevation. Thirty patients requiring sinus elevation had CT images taken with Philips Brilliance iCT. The thickness of the sinus lateral wall was measured according to its vertical position against the sinus inferior border, and its mean was calculated through three repeated measurements. When measured 2 mm above the sinus inferior border (SIB+2), the thickness of the sinus lateral wall was observed to be more than 2 mm. When measured 3 mm above the sinus inferior border (SIB +3), the sinus lateral wall was less than 2 mm in thickness. It is recommended that the lateral wall window be made 3 mm above the sinus inferior border when performing sinus elevation using the lateral approach.

• Imaging Science in Dentistry
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• v.34 no.3
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• pp.129-136
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• 2004

Purpose: To evaluate whether cone beam computed tomography can depict the distribution, position, frequency, relative vertical dimension, and the diameter of the lingual foramen and direction of lingual bone canal. Materials and Methods : Cone beam computed tomography of mandible was performed on 25 males and 25 females with no history of any orthodontic treatments or any other dental surgeries. A statistical comparison was done on the mean values of males and females. Results: In the location and distribution of lingual foramina, median lingual foramen was found in all subjects and lateral lingual foramen in 58%. In the lateral lingual foramen, bilateral type was found in 28% and unilateral type in 30%. In the number of lingual foramina, median lingual foramen had two foramina and lateral lingual foramen had one foramen, mostly. In the relative mean vertical dimension of lingual foramina, median lingual foramen was 0.03±0.08, and both lateral lingual foramina was 0.20±0.04. The mean diameter of lingual foramina, median lingual foramen was 0.9mm±0.28, right lateral lingual foramen was 0.92mm±0.23, and left lateral lingual foramen was 0.88mm±0.27. The most frequent direction of the lingual bone canals, median lingual bone canal proceeded in anteroinferior direction and lateral lingual bone canal in anterosuperolateral direction. Conclusion : Cone beam computed tomography can be helpful for surgery and implantation on the mandibular area. Radiologist should be aware of this anatomical feature and its possible implications.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.29 no.2
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• pp.411-416
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• 1999

Purpose : This study was done to evaluate the absorbed doses in organs of the head and neck for the conventional temporomandibular joint tomography. Materials and Methods : Dosimetry was performed with 32 LiF thermoluminescent dosimeters, which were placed in a tissue-equivalent phantom when the temporomandibular joint was examined by both lateral and frontal temporomandibular joint tomography. Results : For lateral tomography, parotid gland and preauricular area towards tube showed relatively high absorbed dose of 1056.9 μGy and 519.9 μGy respectively. For frontal tomography, the two largest absorbed doses were 259.2 μGy in orbit towards tube and 212.0 μGy in lens towards tube. Conclusion : Conventional temporomandibular joint tomography showed relatively low absorbed doses on critical organs. Thus, responsible use of it may not be limited.

• Imaging Science in Dentistry
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• v.32 no.2
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• pp.67-73
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• 2002

Purpose: To examine the possible relationship between condylar position and disk displacement in the temporomandibular joint. Materials and Methods: 79 temporomandibular joints in 40 patients having temporomandibular disorders were classified into three categories: no disk displacement (NDD) , disk displacement with reduction (DDWR), and disk displacement without reduction (DDWOR). Disk positions were assessed from clinical and MRI findings. The relationship between the three categories and condylar positions was evaluated using lateral individualized corrected tomography. Results: Clinical findings regarding the relationship between condyle and disk positions having anterior, centric, and posterior positions were 27%, 27%, and 46%, respectively, in NDD, 43%, 17%, and 40%, respectively, in DDWR, and 44%, 22%, and 34%, respectively, in DDWOR. There were no significant differences in condylar positions between each of the groups (P>0.05). In the relationship between condyle and disk positions with MRI findings, anterior, centric, and posterior positions were 38%, 38%, and 24%, respectively, in NDD, 29%, 21%, and 50%, respectively, in DDWR, and 44%, 9%, and 47% respectively, in DDWOR. There were significant differences in the condylar positions when MRI was utilized (P<0.05) Conclusion: There was a significant correlation between the condyle and disk positions with MRI findings on lateral individualized corrected tomography.

• Journal of Korean Neurosurgical Society
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• v.55 no.6
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• pp.357-361
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• 2014

Computed tomography angiography (CTA) is commonly used in setting of subarachnoid hemorrhage, but imaging features of aneurysm rupturing taking place at the time of scanning has rarely been described. The author reports a case of actively rebleeding aneurysm of the anterior communicating artery with intraventricular extravasation on the hyperacute CTA imaging. The rebleeding route, not into the third ventricle but into the lateral ventricles, can be visualized by real-time three-dimensional CT pictures. The hemorrhage broke the septum pellucidum and the lamina rostralis rather than the lamina terminalis.

• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.4
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• pp.349-357
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• 2012

The purpose of this study was to measure the thickness of the sinus lateral wall using cone-beam computed tomography (CBCT), and to find the most suitable vertical position for lateral window opening prior to sinus elevation. Fifty three patients requiring sinus elevation had CBCT scans acquired by CB MercuRay (Hitachi, Medico, Tokyo, Japan) from July, 2010 to June, 2012. The thickness of the sinus lateral wall was measured according to its vertical position against the sinus inferior border (SIB), and its mean was calculated through two repeated measurements. The thickness of the sinus lateral wall was more than 2 mm at 2 mm above the sinus inferior border (SIB+2), however, it was less than 2 mm at 3 mm above the sinus inferior border (SIB+3). In conclusion, it is recommended that the inferior border of lateral wall window be made 3 mm above the sinus inferior border during sinus elevation using the lateral approach considering the thickness of the sinus lateral wall.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.5
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• pp.295-304
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• 2012

Objectives: Lateral cephalometry, computed tomography (CT) and full-night polysomnography were used to examine the correlation of obstructive sleep apnea (OSA) severity. Materials and Methods: A total of 29 patients (5 females, 24 males) diagnosed with OSA were evaluated by lateral cephalometry, CT and full-night polysomnography. Lateral cephalometry was performed in the closed and open mouth states. The radiographic and polysomnography measurements of the patients with OSA were evaluated statistically to determine the association with OSA severity. Results: A significant relationship was observed between the increased respiratory disturbance index and closing lateral cephalometry. With mouth opening, the airway space narrowed and the OSA worsened. Lateral cephalometry revealed OSA patients to have an inferiorly positioned hyoid bone, longer-than-normal soft palate and narrowing airway space. As OSA was severe, the airway shape was ovoid in the CT horizontal view. Conclusion: Polysomnography and the radiographic parameter can be used for diagnosing OSA.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.19 no.1
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• pp.151-159
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• 1989

The author has studied radiographic bony cnages of mandibular condyle head in temporomandibular disorder patients using Oblique lateral transcranial projection, Orthopantomography, and Tomography. The bony change types and the frequencies of occurrence and the incidences of bony changes in three different radiographic techniques were examined. The coincidences of bony change types between the Oblique lateral transcranial projection and the lateral part of Tomogram, the Orthopantomogram and the medial part of Tomogram were also examined. The results were as follows: 1. The mean age of patients was 31.7 years and under 40 years were 24 patients, women werw 27 patients, men were 4patients. 2. The observable case of bony changes in all three radiographic techniques were 19 cases (50%) of 38 cases and the observable cases of bony changes in only Tomography were 5 cases(13.2%) 3. The most frequent radiographic bony change type was osteophyte and next orders were flattening, erosion, concavity. 4. The positional incidences of bony change in Tomogram were 31 cases in lateral part and 27 cases in central part. 5. The coincidence of bony change types between the Oblique lateral transcranial projection and the lateral part of Tomogram was 80%, and the coincidence between the Orthopantomogram and the medial part or Tomogram was 76.0%.