• Title/Summary/Keyword: CT scan type

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The Change of Bone Metabolism in Ovariectomized Rats : Analyses of MicroCT Scan and Biochemical Markers of Bone Turnover

  • Yoon, Kyung-Hyuk;Cho, Dae-Chul;Yu, Song-Hee;Kim, Kyoung-Tae;Jeon, Young-Hoon;Sung, Joo-Kyung
    • Journal of Korean Neurosurgical Society
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    • v.51 no.6
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    • pp.323-327
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    • 2012
  • Objective : The purpose of this study was to verify the appropriateness of ovariectomized rats as the osteoporosis animal model. Methods : Twelve female Sprague-Dawley rats underwent a sham operation (the sham group) or bilateral ovariectomy [the ovariectomy (OVX) group]. Eight weeks after operations, serum biochemical markers of bone turnover were analyzed; osteocalcin and alkaline phosphatase, which are sensitive biochemical markers of bone formation, and C-terminal telopeptide fragment of type I collagen C-terminus (CTX), which is a sensitive biochemical marker of bone resorption. Bone histomorphometric parameters and microarchitectural properties of 4th lumbar vertebrae were determined by micro-computed tomographic (CT) scan. Results : The OVX group showed on average 75.4% higher osteocalcin and 72.5% higher CTX levels than the sham group, indicating increased bone turnover. Micro-CT analysis showed significantly lower bone mineral density (BMD) (p=0.005) and cortical BMD (p=0.021) in the OVX group. Furthermore, the OVX group was found to have a significantly lower trabecular bone volume fraction (p=0.002). Conclusion : Our results showed that bone turnover was significantly increased and bone mass was significantly decreased 8 weeks after ovariectomy in rats. Thus, we propose that the ovariectomized rat model be considered a reproducible and reliable model of osteoporosis.

Estimation of Appropriate Number of Radiologic Technologist Based on Analysis of Time Required for Computed Tomography (전산화단층촬영의 소요시간 분석에 기반한 방사선사의 적정인력 산정에 관한 연구)

  • Lee, Ki-Baek;Kim, Yung-Kyoon;Kim, Eun-Hye;Kim, Yon-Min
    • Journal of radiological science and technology
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    • v.45 no.3
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    • pp.213-223
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    • 2022
  • Although the number of computed tomography(CT) is increasing every year, it is insufficient to establish appropriate workload calculation standards of radiologic technologist to provide optimal medical services to patients, such as patient safety management and infection management. The purpose of this study is to present guidelines for calculating the appropriate workload of radiologic technologist by analyzing the work flow of CT procedures and the time required for CT examination in major hospitals. As for the study subjects and methods, the appropriate process for each step of CT examination was investigated to systematically present the process and time required for the actual examination, and the CT procedure time of 104,105 adult patients and 465 pediatric patients under the age of 6 were analyzed. For the time required, data according to the use of contrast medium, procedure type, and adult/child were collected and compared. The test time of CT examination using contrast medium took about 13 minutes when one radiologic technologist worked and about 9 minutes when two radiologic technologists worked. The time required for the procedures were statistically significant depending on the presence or absence of contrast medium, multi-phase procedure, and patient age (considering pediatric patients). As a result, in order to thoroughly perform patient safety and infection management, the appropriate workload increased by about 40% when there were two radiologic technologists. The limit workload was an average of 32 people per day with one radiologic technologist per 15 minutes, and 48 people per day with two radiologic technologist per 10 minutes. This is a marginal workload, and in the case of procedures that require more time to acquire radiographic images, the interval between reservations should be widened.

Influence of the Alveolar Cleft Type on Preoperative Estimation Using 3D CT Assessment for Alveolar Cleft

  • Choi, Hang Suk;Choi, Hyun Gon;Kim, Soon Heum;Park, Hyung Jun;Shin, Dong Hyeok;Jo, Dong In;Kim, Cheol Keun;Uhm, Ki Il
    • Archives of Plastic Surgery
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    • v.39 no.5
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    • pp.477-482
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    • 2012
  • Background The bone graft for the alveolar cleft has been accepted as one of the essential treatments for cleft lip patients. Precise preoperative measurement of the architecture and size of the bone defect in alveolar cleft has been considered helpful for increasing the success rate of bone grafting because those features may vary with the cleft type. Recently, some studies have reported on the usefulness of three-dimensional (3D) computed tomography (CT) assessment of alveolar bone defect; however, no study on the possible implication of the cleft type on the difference between the presumed and actual value has been conducted yet. We aimed to evaluate the clinical predictability of such measurement using 3D CT assessment according to the cleft type. Methods The study consisted of 47 pediatric patients. The subjects were divided according to the cleft type. CT was performed before the graft operation and assessed using image analysis software. The statistical significance of the difference between the preoperative estimation and intraoperative measurement was analyzed. Results The difference between the preoperative and intraoperative values were $-0.1{\pm}0.3cm^3$ (P=0.084). There was no significant intergroup difference, but the groups with a cleft palate showed a significant difference of $-0.2{\pm}0.3cm^3$ (P<0.05). Conclusions Assessment of the alveolar cleft volume using 3D CT scan data and image analysis software can help in selecting the optimal graft procedure and extracting the correct volume of cancellous bone for grafting. Considering the cleft type, it would be helpful to extract an additional volume of $0.2cm^3$ in the presence of a cleft palate.

Evaluation of Artifact and Noise in the Standard and MAR Algorithms with Variation of Examination Conditions of CT (Standard와 MAR 알고리즘에서 CT 검사조건 변화에 따른 인공물과 노이즈 평가)

  • Kim, Young-kuen;Yang, Sook;Wang, Tae-uk
    • Journal of radiological science and technology
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    • v.43 no.2
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    • pp.79-85
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    • 2020
  • The influence of metal artifact in CT image depends on the type of metal materialsm, the reconstruction algorithm, and scan parameters. The presence of metal artifacts was quantitatively evaluated by applying the standard and MAR algorithms through the phantom study. In the change of tube voltage applied the standard algorithm, metal artifact decreased to 44.9% for 80 vs 120 kVp, 24% for 100 vs 120 kVp, while the image taken at 140 kVp increased the artifact by 19% compared to 120 kVp. When the tube current was increased from 100 to 300 mA, there was no significant difference in the CT value and noise. Black band and white strike artifacts occurred up to 65.9% in the adjacent ROI of the metal driver, whereas titanium screw produced lesser metal artifact than that of the metal driver. The combination of 120kVp or higher tube voltage-standard algorithm was effective in removing black band artifacts as well as white streak by high density materials. However, MAR reconstruction algorithm was useful in improving image quality under the environment of low kVp and high density materials, without increase of radiation exposure.

Clinical Analysis of the Mediatinal Neurogenic Tumor -18 case report- (종격동에 빈발하는 신경종에 대한고찰 -18례 임상 경험-)

  • 최영호
    • Journal of Chest Surgery
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    • v.27 no.11
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    • pp.938-941
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    • 1994
  • Neurogenic tumors of the mediastinum may have an intraspinal component connected by a narrowed segment of tumor in the intervertebral foramen, then have symptoms of back pain,lower extremity tingling sensation. CT scan or MRI demonstrated a Dumbbell-shaped mass density compressing spinal canal, enlargement of the foramen, erosion of bone, and intervertebral widening. We report the analysis of the 18 cases of neurogenic tumors on posterior mediastinum and Dumbbell type tumors are 3 cases among the 18 cases. The neurilemmomas were 12 cases[67%], the ganglioneuroma were 5 cases[28%], and neuroblastoma was one case[5%]. The successful removal was done in all cases, a standard thoracotomy and laminectomy was done in Dumbbell type tumors.There was no postoperative neurological complications.

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A Case of Primary Cutaneous Adenoid Cystic Carcinoma at the Genital Area (외음부에 발생한 원발성 피부 선상 낭종성 암의 치험례)

  • Jeong, Hoi Joon;Son, Dae Gu;Kwon, Sun Young
    • Archives of Plastic Surgery
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    • v.35 no.3
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    • pp.333-336
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    • 2008
  • Purpose: Adenoid cystic carcinoma is a rare type of eccrine sweat gland carcinoma. Although it is mostly known as a neoplasm of the salivary gland, it could occur as a primary skin tumor. We present a patient with a primary cutaneous adenoid cystic carcinoma at the genital area. Methods: A 60-year-old man had a slowly growing 1 cm sized single tender mass near the left scrotum and he underwent excisional biopsy at a local clinic. A diagnosis of adenoid cystic carcinoma was made and thus he was transferred to our hospital. In physical examination, other specific findings were not detected except a linear scar caused by a previous skin biopsy near the left scrotum. In CT scan, PET-CT scan and endoscopy, there was no evidence of neoplasm in other organs. It was diagnosed as the primary cutaneous adenoid cystic carcinoma and then wide excisions were performed including total 4.5 cm margin of normal skin. Results: Microscopic findings revealed proliferation of tumor cell islands with cribriform or tubular patterns containing several round, pseudocystic structures. The tumor cells showed basaloid cells with uniform and small nuclei. Tumor cells infiltrated into the dermis and upper portion of subcutaneous tissue. There was multifocal perineural invasion of tumor cells. In postoperative 6 months, we found no recurrence and other complications. Conclusion: Herein we found a rare case of primary cutaneous adenoid cystic carcinoma at the genital area.

Comparative clinical and radiologic evaluation between patients undergoing standard reversed shoulder arthroplasty or bony increased offset

  • Tiago Amorim-Barbosa;Ana Ribau;Helder Fonte;Luis Henrique Barros;Rui Claro
    • Clinics in Shoulder and Elbow
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    • v.26 no.1
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    • pp.3-9
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    • 2023
  • Background: Modifications of the medialized design of Grammont-type reverse shoulder arthroplasty (RSA) using a bony increased offset (BIO-RSA) has shown better clinical results and fewer complications. The aim of this study is to compare the clinical results, complications, and radiological outcomes between patients undergoing standard RSA and BIO-RSA. Methods: A retrospective review was performed of 42 RSA procedures (22 standard RSA and 20 BIO-RSA). With a minimum of 1 year of follow-up, range of motion (ROM), Constant shoulder score (CSS), visual analog scale (VAS), and subjective shoulder score (SSS) were compared. Radiographs and computed tomography (CT) scan were examined for scapular notching, glenoid and humeral fixation, and graft healing. Results: At a mean follow-up of 27.6 months (range, 12-48 months), a significant difference was found for active-internal rotation (P=0.038) and for passive-external rotation (P=0.013), with better results in BIO-RSA. No other differences were found in ROM, CSS (P=0.884), VAS score, and SSS. Graft healing and viability were verified in all patients with CT scan (n=34). The notching rate was 28% in the standard RSA group and 33% in the BIO-RSA group, but the standard RSA had more severe notching (grade 2) than BIO-RSA (P=0.039). No other significative differences were found in glenoid and humeral fixation. Conclusions: Bone-graft lateralization is associated with better internal and external rotation and with less severe scapular notching compared to the standard RSA. Integration of the bone graft occurs effectively, with no relevant changes observed on radiographic evaluation. Level of evidence: III.

The Evaluation of Quantitative Accuracy According to Detection Distance in SPECT/CT Applied to Collimator Detector Response(CDR) Recovery (Collimator Detector Response(CDR) 회복이 적용된 SPECT/CT에서 검출거리에 따른 정량적 정확성 평가)

  • Kim, Ji-Hyeon;Son, Hyeon-Soo;Lee, Juyoung;Park, Hoon-Hee
    • The Korean Journal of Nuclear Medicine Technology
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    • v.21 no.2
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    • pp.55-64
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    • 2017
  • Purpose Recently, with the spread of SPECT/CT, various image correction methods can be applied quickly and accurately, which enabled us to expect quantitative accuracy as well as image quality improvement. Among them, the Collimator Detector Response(CDR) recovery is a correction method aiming at resolution recovery by compensating the blurring effect generated from the distance between the detector and the object. The purpose of this study is to find out quantitative change depending on the change in detection distance in SPECT/CT images with CDR recovery applied. Materials and Methods In order to find out the error of acquisition count depending on the change of detection distance, we set the detection distance according to the obit type as X, Y axis radius 30cm for circular, X, Y axis radius 21cm, 10cm for non-circular and non-circular auto(=auto body contouring, ABC_spacing limit 1cm) and applied reconstruction methods by dividing them into Astonish(3D-OSEM with CDR recovery) and OSEM(w/o CDR recovery) to find out the difference in activity recovery depending on the use of CDR recovery. At this time, attenuation correction, scatter correction, and decay correction were applied to all images. For the quantitative evaluation, calibration scan(cylindrical phantom, $^{99m}TcO_4$ 123.3 MBq, water 9293 ml) was obtained for the purpose of calculating the calibration factor(CF). For the phantom scan, a 50 cc syringe was filled with 31 ml of water and a phantom image was obtained by setting $^{99m}TcO_4$ 123.3 MBq. We set the VOI(volume of interest) in the entire volume of the syringe in the phantom image to measure total counts for each condition and obtained the error of the measured value against true value set by setting CF to check the quantitative accuracy according to the correction. Results The calculated CF was 154.28 (Bq/ml/cps/ml) and the measured values against true values in each conditional image were analyzed to be circular 87.5%, non-circular 90.1%, ABC 91.3% and circular 93.6%, non-circular 93.6%, ABC 93.9% in OSEM and Astonish, respectively. The closer the detection distance, the higher the accuracy of OSEM, and Astonish showed almost similar values regardless of distance. The error was the largest in the OSEM circular(-13.5%) and the smallest in the Astonish ABC(-6.1%). Conclusion SPECT/CT images showed that when the distance compensation is made through the application of CDR recovery, the detection distance shows almost the same quantitative accuracy as the proximity detection even under the distant condition, and accurate correction is possible without being affected by the change in detection distance.

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A Clinical Study on the Factors that Influence Functional Evaluation of Stroke (중풍의 기능평가에 영향을 미치는 요인에 관한 임상적 고찰)

  • 박숙자;권정남;김영균
    • The Journal of Korean Medicine
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    • v.23 no.4
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    • pp.73-90
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    • 2002
  • Objectives: This study investigated significant factors that influence functional evaluation of stroke so as to be a fundamental data for estimating prognosis of stroke patients. Methods: 204 patients were studied within 7 days of admission, after the diagnosis of stroke through brain CT scan, brain MRI scan and clinical observations. They were hospitalized in the oriental medical hospital of Dongeui University from February to July in 2001. They were examined at the early stage of onset, after 2 weeks, 4 weeks and 6 weeks, and measured for average mark and the degree of improvement by using the Activity Index. Results: Ischemic stroke, past history of stroke, hypertension, diabetes mellitus, risk factor of obesity, non-professional emergency treatment and hospitalizing time after 1 day from onset, high blood pressure, tachycardia pulse and high blood sugar in abnormal vital sign in acute stage, conscious, cognitive or communication disorder, motor aphasia, dysphagia, constipation for more than 3 days, urinary incontinence, visual field defect, insomnia, and chest discomfort in early stage of onset had a negative influence on functional evaluation. Conclusions: Type of stroke, past history, risk factors, emergency treatment and hospitalizing time after onset, abnormal vital sign and intercurrent symptoms in Acute stage were relevant factors in predicting functional evaluation of stroke.

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Glue Embolization of Ruptured Anterior Thalamoperforating Artery Aneurysm in Patient with Both Internal Carotid Arteries Occlusion

  • Lee, Jae-Il;Choi, Chang-Hwa;Ko, Jun-Kyeung;Lee, Tae-Hong
    • Journal of Korean Neurosurgical Society
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    • v.49 no.5
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    • pp.287-289
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    • 2011
  • Thalamoperforating artery aneurysms are rarely reported in the literature. We report an extremely rare case of ruptured distal anterior thalamoperforating artery aneurysm which was treated by endovascular obliteration in a patient with occlusion of both the internal carotid arteries (ICAs) : A 72-year-old woman presented with severe headache and loss of consciousness. Initial level of consciousness at the time of admission was drowsy and the Glasgow Coma Scale score was 14. Brain computed tomography (CT) scan was performed which revealed intracerebral hemorrhage in right basal ganglia, subarachnoid hemorrhage, and intraventricular hemorrhage. The location of the aneurysm was identified as within the globus pallidus on CT angiogram. Conventional cerebral angiogram demonstrated occlusion of both the ICAs just distal to the fetal type of posterior communicating artery and the aneurysm was arising from right anterior thalamoperforating artery (ATPA). A microcatheter was navigated into ATPA and the ATPA proximal to aneurysm was embolized with 20% glue. Post-procedural ICA angiogram demonstrated no contrast filling of the aneurysm sac. The patient was discharged without any neurologic deficit. Endovascular treatment of ATPA aneurysm is probably a more feasible and safe treatment modality than surgical clipping because of the deep seated location of aneurysm and the possibility of brain retraction injury during surgical operation.