• Journal of Korean Neurosurgical Society
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• 제64권2호
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• pp.247-254
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• 2021

Objective : The subaxial cervical pedicle screwing technique shows powerful biomechanical properties for posterior cervical fusion. When applying a pedicle screw using the freehand technique, it is essential to analyse cervical computed tomography and plan the surgery accordingly. Normal cervical computed tomography is usually performed in the supine position, whereas during surgery, the patient lies in a prone position. This fact leads us to suppose that radiological evaluations may yield misleading results. Our study aimed to investigate whether there is any superiority between preoperative preparation on computed tomography performed in the prone position and that performed in the supine position. Methods : This study included 17 patients (132 pedicle screws) who were recently operated on with cervical vertebral computed tomography in the prone position and 17 patients (136 pedicle screws) who were operated on by conventional cervical vertebral computed tomography as the control group. The patients in both groups were compared in terms of age, gender, pathological diagnosis, screw malposition and complications. A screw malposition evaluation was made according to the Gertzbein-Robbins scale. Results : No statistically significant difference was observed between the two groups regarding age, gender and pathological diagnosis. The screw malposition rate (from 11.1% to 6.9%, p<0.05), mean malposition distance (from 2.18 mm to 1.86 mm, p <0.05), and complications statistically significantly decreased in the prone position computed tomography group. Conclusion : Preoperative surgical planning by performing cervical vertebral computed tomography in the prone position reduces screw malposition and complications. Our surgical success increased with a simple modification that can be applied by all clinicians without creating additional radiation exposure or additional costs.

• 구강회복응용과학지
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• 제32권1호
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• pp.87-92
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• 2016

이 임상증례의 목적은 상악 제2대구치의 해부학적 형태를 computed tomography (CT)를 이용해 확인하여 근관치료에 활용한 증례이다. 이번 증례에서는 두개의 구개치근을 갖는 상악 제 2대구치에서 성공적인 근관치료를 위해서 CT를 활용하여 해부학적 형태를 확인하여 활용하였다. Cone beam computed tomography (CBCT)의 사용은 구개치근과 협측치근이 겹쳐보이는 치근단 방사선 사진의 한계를 극복할 수 있게 한다.

• Journal of Gastric Cancer
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• 제13권3호
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• pp.149-156
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• 2013

Purpose: Clinical stage of gastric cancer is currently assessed by computed tomography. Accurate clinical staging is important for the tailoring of therapy. This study evaluated the accuracy of clinical N staging using stomach protocol computed tomography. Materials and Methods: Between March 2004 and November 2012, 171 patients with gastric cancer underwent preoperative stomach protocol computed tomography (Jeju National University Hospital; Jeju, Korea). Their demographic and clinical characteristics were reviewed retrospectively. Two radiologists evaluated cN staging using axial and coronal computed tomography images, and cN stage was matched with pathologic results. The diagnostic accuracy of stomach protocol computed tomography for clinical N staging and clinical characteristics associated with diagnostic accuracy were evaluated. Results: The overall accuracy of stomach protocol computed tomography for cN staging was 63.2%. Computed tomography images of slice thickness 3.0 mm had a sensitivity of 60.0%; a specificity of 89.6%; an accuracy of 78.4%; and a positive predictive value of 78.0% in detecting lymph node metastases. Underestimation of cN stage was associated with larger tumor size (P<0.001), undifferentiated type (P=0.003), diffuse type (P=0.020), more advanced pathologic stage (P<0.001), and larger numbers of harvested and metastatic lymph nodes (P<0.001 each). Tumor differentiation was an independent factor affecting underestimation by computed tomography (P=0.045). Conclusions: Computed tomography with a size criterion of 8 mm is highly specific but relatively insensitive in detecting nodal metastases. Physicians should keep in mind that computed tomography may not be an appropriate tool to detect nodal metastases for choosing appropriate treatment.

• 한국임상수의학회지
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• 제24권4호
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• pp.667-672
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• 2007

This report describes the use of conventional computed tomography(CT) for the diagnosis of head trauma in three canine patients. According to physical and neurologic examinations, survey radiography and computed tomography, these patients were diagnosed as traumatic brain injury. Especially, CT is the imaging modality of first choice for head trauma patients. It provides rapid acquisition of images, superior bone detail, and better visualization of acute hemorrhage than magnetic resonance imaging. It is also less expensive and more readily available. Pre-contrast computed tomography was used to image the head. Then, post-contrast CT was performed using the same technique. The Modified Glasgow Coma Scale(MGCS) score was used to predict their probability of survival rate after head trauma in these dogs. Computed tomogram showed fluid filled tympanic bulla, fracture of the left temporal bone and cerebral parenchymal hemorrhage with post contrast ring enhancement. However, in one case, computed tomographic examination didn't delineate cerebellar parenchymal hemorrhage, which was found at postmortem examination. Treatments for patients placed in intensive care were focused to maintain cerebral perfusion pressure and to normalize intracranial pressure. In these cases, diagnostic computed tomography was a useful procedure. It revealed accurate location of the hemorrhage lesion.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 추계학술대회 논문집
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• pp.697-698
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• 2012

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.963-964
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• 2013

• Imaging Science in Dentistry
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• 제43권3호
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• pp.209-213
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• 2013

It has been a challenge to establish the accurate diagnosis of developmental tooth anomalies based on periapical radiographs. Recently, three-dimensional imaging by cone beam computed tomography has provided useful information to investigate the complex anatomy of and establish the proper management for tooth anomalies. The most severe variant of dens invaginatus, known as dilated odontome, is a rare occurrence, and the cone beam computed tomographic findings of this anomaly have never been reported for an erupted permanent maxillary central incisor. The occurrence of talon cusp occurring along with dens invaginatus is also unusual. The aim of this report was to show the importance of cone beam computed tomography in contributing to the accurate diagnosis and evaluation of the complex anatomy of this rare anomaly.

• Journal of Chest Surgery
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• 제28권1호
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• pp.37-41
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• 1995

To determine the role of mediastinoscopy in the preoperative staging of the primary lung cancer, we studied 23 patients from January 1993 to December 1993 and compared the results of mediastinoscopy and computed tomographic scanning with the findings at thoracotomy. Mediastinoscopy was performed in 14 patients when they had larger than 10mm mediastinal nodes at computed tomographic scanning. Six of them were found to have metastatic nodes. Nine patients, who had negative computed tomographic scanning and negative mediastinoscopic results,underwent thoracotomy. One of them was found to have a metastatic mediastinal lymph node. When results from both series of patients were compared, the sensitivity and specificity of computed tomographic scanning showed 83.3% and 47.1% respectively with an accuracy of 56.5%. The results of mediastinoscopy showed that the sensitivity was 85.7%, the specificity was 100% and the accuracy was 95.7%.Because of the low accuracy rate of computed tomographic scanning, a more routine use of mediastinoscopy seems to be justified.

• Imaging Science in Dentistry
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• 제48권3호
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• pp.223-226
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• 2018

This report presents a case of cervical pneumatocysts as an incidental finding on cone-beam computed tomography. Pneumatocysts are gas-containing lesions of unknown etiology. They usually present in the ilium or sacrum, adjacent to the sacroiliac joint. In the literature, 21 case reports have described cervical pneumatocysts. Cervical pneumatocysts should be differentiated from other lesions, such as osteomyelitis, osteonecrosis, and neoplasms, as well as post-traumatic and post-surgical cases. Computed tomography, cone-beam computed tomography, and magnetic resonance imaging are appropriate tools to diagnose cervical pneumatocysts.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권4호
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• pp.391-396
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• 2006

The CT number is called Hounsfield unit(HU). Generally HU has a score between +1000 from -1000, and it is standardized usingthe air(-1000), water(0), and compact bone(+1000). Hounsfield Unit to standardize the density in computed tomography using the air and water has been used to analysis of lesion in other medical field. Computed tomography is popular method to analysis of lesion in oral & maxillofacial field but the analysis about density of lesion by Hounsfield unit is still obscure. For this study, computed tomography taken in Dankook University Dental Hospital and Hounsfield unit was measured to compare the difference of jaw bone lesion as cystic lesion, benign tumor, malignant tumor.