• Progress in Medical Physics
• /
• v.27 no.2
• /
• pp.72-78
• /
• 2016

A CCD camera and an LED light source were combined to fabricate a compact optical CT scanner for the therapeutic radiation dose evaluation of a polymer gel dosimeter. After the collimated beam emitted by the LED passed through aquarium, gel phantom, and telecentric lens, an image was collected by the CCD camera and reconstructed using MATLAB. By using a stepping motor and LabVIEW, the gel dosimeter was rotated at every $0.72^{\circ}$, and the time for collecting 500 slice images per a revolution was within 20 min. At a spatial frequency of 4.5 lp/mm of the optical CT scanner, the modulation transfer function value was 72%. The linear correlation coefficient of the optical CT scanner for the polymer gel dosimeter was 0.987.

• Progress in Medical Physics
• /
• v.9 no.1
• /
• pp.47-53
• /
• 1998

Nuclear Medicine Images have comparatively poor spatial resolution, making it difficult to relate the functional information which they contain to precise anatomical structures. Anatomical structures useful in the interpretation of SPECT /PET Images were radiolabelled. PET/SPECT Images Provide functional information, whereas MRI mainly demonstrate morphology and anatomical. Fusion or Image Registration improves the information obtained by correlating images from various modalities. Brain Scan were studied on one or more occations using MRI and SPECT. The data were aligned using a point pair methods and surface matching. SPECT and MR Images was tested using a three dimensional water fillable Hoffman Brain Phantom with small marker and PET and MR Image was tested using a patient data. Registration of SPECT and MR Images is feasible and allows more accurate anatomic assessment of sites of abnormal uptake in radiolabeled studies. Point based registration was accurate and easily implemented three dimensional registration of multimodality data set for fusion of clinical anatomic and functional imaging modalities. Accuracy of a surface matching algorithm and homologous feature pair matching for three dimensional image registration of Single Photon Emission Computed Tomography Emission Computed Tomography (SPECT), Positron Emission Tomography (PET) and Magnetic Resonance Images(MRD was tested using a three dimensional water fill able brain phantom and Patients data. Transformation parameter for translation and scaling were determined by homologous feature point pair to match each SPECT and PET scan with MR images.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2024.01a
• /
• pp.17-18
• /
• 2024

악성 흉수의 진단은 세포학적 검사로 암세포를 확인하는 것이 필수적이며 진단율은 50~80%로 나타난다. 양성자 단층 촬영은 비침습적으로 암 병기를 평가하는 유용한 방법이다. 하지만 암이 아닌 다른 원인으로 인한 포도당 대사로 인하여 양전자 단층 촬영만으로 악성 흉수를 진단하는 데 어려움이 있다. 악성 흉수 자동 진단 모델은 암세포를 진단하는데 있어서 보조적인 역할이 가능하다. 이에 따라 본 연구는 컨볼루션 신경망 기반의 딥러닝 모델을 개발하여 악성 흉수 진단 성능을 확인하고 진단의 보조적 목적으로써 딥러닝의 사용 가능성을 확인하고자 하였다. 결과적으로 모델 전반적으로 accuracy 0.7~0.86의 높은 성능을 보였다. 본 연구의 결과를 통해 실제 의료 환경에서 악성 흉수를 진단하는데 딥러닝 모델이 보조적인 역할을 할 수 있을 것으로 기대된다.

• Journal of the Korean Society of Radiology
• /
• v.84 no.2
• /
• pp.372-385
• /
• 2023

Breast cancer is one of the most common cancers and causes several complications in females. Currently, MRI is a necessary method for preoperative studies in patients with breast cancer. A high frequency of breast MRI can lead to an increase in the number of incidental extramammary findings. Moreover, it can provide accurate preoperative workup; therefore, the prognosis of patients can be improved. Herein, we provide several extramammary findings, including the mediastinum, lung, upper abdomen, bone, and soft tissue, correlating with US, chest CT, liver MRI, PET-CT, and bone scan.

• The Magazine of the IEIE
• /
• v.12 no.5
• /
• pp.59-65
• /
• 1985

• The Academic Congress of Korean Shoulder and Elbow Society
• /
• 2009.03a
• /
• pp.23-24
• /
• 2009

• Journal of Veterinary Clinics
• /
• v.30 no.5
• /
• pp.366-370
• /
• 2013

A 7-month-old Pomeranian presented with non-weight bearing lameness on the right pelvic limb. Physical examination revealed pain on extension of the right hip joint, and serum chemistry results showed an increased concentration of creatine kinase. Radiographic findings at admission included a weak radiolucent line on the right femoral head and widening of the right hip joint space, and mild displacement of the right capital femoral epiphysis was additionally identified on day 14. Computed tomography (CT) showed a decreased Hounsfield Unit measurement and a fracture line on the right femoral head. Early stage Legg-Calve-Perthes disease (LCPD) was diagnosed and femoral head and neck ostectomy was performed on the right femur. A fracture fissure and osteophytes at the epiphyseal plate of the femoral head were identified surgically. Necrosis in the femoral metaphysis and epiphysis was observed histologically. This case report describes the radiography, CT images, and surgical and histological findings in a dog with early stage LCPD.

• Journal of Veterinary Clinics
• /
• v.32 no.2
• /
• pp.196-199
• /
• 2015

A 7-year-old intact female dachshund (Dog 1) and a 17-year-old intact male Yorkshire terrier (Dog 2) were presented for evaluation of mammary gland tumor and a regular checkup, respectively. Incidentally, segmental caudal vena cava aplasia was detected on CT images in both dogs. Absent postrenal segment (Dog 1) or discontinuation of caudal vena cava (Dog 2) were detected, but prerenal segment of caudal vena cava was continued to the dilated azygos vein. Segmental CVC aplasia should be considered when an abdominal vascular anomaly was evaluated with CT angiography in dogs.

• Journal of Veterinary Clinics
• /
• v.29 no.2
• /
• pp.190-193
• /
• 2012

A 2-month-old, intact female Alaskan Malamute was presented for evaluation of dyspnea and subcutaneous emphysema of the neck following biting wound. Two small punctured skin lesions and crepitus on the neck were found during physical examination. Radiographs revealed pneumomediastinum and subcutaneous emphysema. Confirmative diagnosis of tracheal laceration was made by identifying the tracheal wall discontinuity on the computed tomography. CT is a valuable tool to diagnose an external traumatic tracheal injury, and more specifically, to assess the location and the extent of laceration, and it leads to early definitive treatment and reduction of the incidence of complications.

• Journal of the Korean Society of Radiology
• /
• v.15 no.3
• /
• pp.293-299
• /
• 2021

In order to reduce the irresistible radiation exposure of patients who perform periodic examinations using a CT among various scan parameters a method to reduce patient dose was investigated through changes in the tube voltage close to X-ray penetrating power. As a result of the experiment 100 kVp was applied instead of 120 kVp which is commonly used in clinical practice and CTDI decreased by about 41% during scan. In addition the degree of change in image quality was measured as 1046.1±3.7 HU for CT value and 71.4±7.9 for Pixel value and statistical analysis showed no significant difference (0.05