1.Invasive thymoma; radiologic evaluation by computed tomography
Journal of the Korean Radiological Society 1985;21(2):237-245
In 6 cases of invasive thymoma proved histologically from 1981 to 1984 in Yonsei University Medical Center,the CT findings and pattern were analysed. The results were as follows 1. Of 6 case, 4 were males and 2 werefemales. All cases were between 40-64 years and the average was 51 year old. 2. Of 6 cases, 2 female patients wereassociated with myasthenia gravis. 3. By the histological examination, 2 were confirmed as mixed cell type, 2spindle cell type, 1 lymphocytic type and 1 epithelial cell type. 4. CT findings of invasive thymoma were 1) Adiscrete but lobulated and irregular marginated soft tissue mass in the superoanterior mediastinum replacing thenormal mediastinal fat tissue. 2) Usually irregular low density areas within the mass suggesting central necrosisor calcification in 1 of 6 cases was noted. 3) Local invasiveness of the mass shown as obliteration of the normalfat planes surrounding great vessels, irregular thickenings or nodular shadows of the pleura, diagphragm andpericardium and irregular and ragged tumor-lung interfaces if the tumor invaded to these structures. 4) Frequentextention of tumor to middle and post. mediastinum along pericardium or mediastinal pleura with resultantextrinsic indentation and/or invasion of the hilar region. 5) Extensive tumor infiltration to middle and post.mediastinum in 1 case, indistinguishable from lymphoma. 6) Low attenuation numbered area of brain in another 1case, but not confirmed histologically.
Brain
;
Epithelial Cells
;
Female
;
Humans
;
Lymphoma
;
Male
;
Mediastinum
;
Myasthenia Gravis
;
Pericardium
;
Pleura
;
Thymoma
2.Trichobezoar dectected by ultrasonography: case report.
Choon Sik YOON ; Myung Jun KIM ; Ki Keun OH
Journal of the Korean Radiological Society 1993;29(4):849-852
The authors experienced a case of gastroduodenojejunal trichobezoar detected by ultrasongraphic examination. We thought that tricholbezoar had relatively specific ultrasonographic findings such as a broad hyperechogenic superficial bandlike rim with a complete posteior sonic shadowing and multiple linear echogenic strands on its surface representing hairs, which were better seen after water ingestion. So we were able to get the correct diagnosis of trichobezoar prior to conventional barium studies in a patient who could not be suspected suspected clinically.
Barium
;
Bezoars*
;
Diagnosis
;
Eating
;
Hair
;
Humans
;
Shadowing (Histology)
;
Ultrasonography*
;
Water
3.Magnetic Resonance Imaging Findings of Intraspinal Neurenteric Cyst: Case Report.
Dong Ik KIM ; Choon Sik YOON ; Pyeong Ho YOON ; Tae Sub CHUNG ; Sang Wook YOON
Journal of the Korean Radiological Society 1994;31(4):621-625
Intraspinal neurenteric cysts are rare congenital lesions that results from abnormal separation of germ layers in the third week of embryonic development, which may cause spinal compression. Although, the diagnosis of neurenteric cyst was very difficult prior to operation, MRI has proven to be a useful imaging modality in detection, localization and characterization of intraspinal neurenteric cysts. We recently experienced intraspinal neurenteric cyst in two patients who presented with progerssive quadriparesis. Myelography, CT myelography and MRI were taken and complete excision was performed. The MRI findings are presented and the literature is reviewed.
Diagnosis
;
Embryonic Development
;
Female
;
Germ Layers
;
Humans
;
Magnetic Resonance Imaging*
;
Myelography
;
Neural Tube Defects*
;
Pregnancy
;
Quadriplegia
4.MRI of Epidural Cavernous IVlalformations of the Spine: Correlation with Surgical and Histopathologic Findings.
Dong Ik KIM ; Choon Sik YOON ; Pyeong Ho YOON ; Tae Sub CHUNG ; Jung Ho SUH
Journal of the Korean Radiological Society 1994;30(3):411-415
PURPOSE: The purpose of this study is to describe Magnetic Resonance(MR) findings of two epidural cavernous malformations of the spine. MATERIALS AND METHODS: MR imaging was performed in 2 patients(29-year-old man and 54-year-old woman). Sagittal T1 -, T2-weighted images and Gadolinium (Gd)-enhanced axial and sagittal images were acquired. Two patients had surgery and MR findings were compared with surgical and histopathological findings. RESULTS: MR imaging showed high- and low-signal intensity components of these lesions that were characteristic of an epidural cavernous malformation in one case. The other case showed a high signal intensity on T2- and strong enhancement on Gd-enhanced T1 -weighted images. We think that the former may be due to mixed subacute and chronic hemorrhage and the latter may be due to blood within the endotheliumlined sinusolds without hemorrhage. CONCLUSION: These findings were well correlated with the surgical and histo-pathological findings of cavernous malformation.
Gadolinium
;
Hemorrhage
;
Humans
;
Magnetic Resonance Imaging*
;
Middle Aged
;
Spine*
5.Breast hamartoma: 3 case report.
Ki Keun OH ; Hee Sung HWANG ; Choon Sik YOON ; Jin Sik MIN ; Kyong Sik LEE ; Hyeon Joo JEONG
Journal of the Korean Radiological Society 1991;27(1):77-81
No abstract available.
Breast*
;
Hamartoma*
6.Radiologic findings of mesoblastic nephroma.
Sei Jung OH ; Choon Sik YOON ; Ki Keun OH ; Myung Joon KIM
Journal of the Korean Radiological Society 1992;28(3):453-456
The mesoblastic nephroma is a rare benign renal tumor that frequently appears as a neonatal abdominal mass. This benign tumor is composed primarily of connective tissue that growth between intact nephrons and often replaces most of the renal parenchyme. Contrast media within the calyceal systems are seen within the tumor representing function by nephrons trapped within the mass. Prognosis after complete excision is excellent.
Connective Tissue
;
Contrast Media
;
Nephroma, Mesoblastic*
;
Nephrons
;
Prognosis
7.Ultrasonographic Evaluation of Fibroadenoma in the Breast: Primary Signs of Mass.
Mi Hye KIM ; Ki Keun OH ; Choon Sik YOON ; Chang Soo AHN
Journal of the Korean Radiological Society 1994;30(1):193-196
PURPOSE: To evaluate the ultrasonomammographic findings of breast fibroadenoma. METHODS AND MATERIALS:We evaluated the ultrasonographic findings of histopathologically proved 135 fibroadenomas in 103 patients from January 1986 to September 1990, retrospectively. The ultrasonographic examinations were performed with a hand held linear array 5MHz transducer(Acuson 128(USA). Aloka 650, 280(Japan)). A sonopad was also used during the examinations. RESULTS: The common ultrasonographic findings of fibroadenomas usually showed smooth contour in 120 lesions(88.9% ), oval or round shape in 114 lesions(84.4%), uniform homogeneous echogenecity in 106 lesions(78.5% ), intermediate hypoechoic internal echo pattern in 105 lesions(77.8%), thin boundary echo in 117 lesions(86.7%), lateral shadowings in 97 lesions(72%), and posterior acoustic enhancement in 56 lesions(41%). The longitudinal/transverse ratio of fibroadenoma was revealed between 0.2 and 1.14 (mean 0.58) and usually under 1.0 (68.9%). CONCLUSION: Finally, most of fibroadenomas are easily diagnosed by ultrasonography but if differential diagnosis from malignant breast mass is difficult due to atypical appearance, other combined modalities such as filmmammography, fine needle aspiration biopsy and MRI are necessary.
Acoustics
;
Biopsy
;
Biopsy, Fine-Needle
;
Breast*
;
Diagnosis, Differential
;
Fibroadenoma*
;
Hand
;
Humans
;
Magnetic Resonance Imaging
;
Retrospective Studies
;
Shadowing (Histology)
;
Ultrasonography
8.Neuroblastoma: Computed Tomographic Findings.
Choon Sik YOON ; Chang Su AHN ; Myung Jun KIM ; Ki Keun OH
Journal of the Korean Radiological Society 1994;30(1):187-192
PURPOSE: To evaluate the characteristic CT findings of neuroblastoma, we studied neurobalstomas. METHODS AND MATERIALS: We analysed CT findings of available 25 cases among pathologically proved 51 neurobalstomas from Jan. 1983 to Sept. 1990. RESULTS: The most frequent site of origin is adrenl gland (40%) and the second is retroperitoneum (32%) and the third ismediastinum (16%). Characteristic CT findings are as follows:Calcifications within the tumor is detected in 86% of abdominal neuroblastomas and 50% of mediastinal origin. Hemorrhagic and necrotic changes within the tumor is noted at 86% in the tumor of abdominal origin and 25% in mediastinal neuroblastomas. Contrast enhanced study showed frequently septated enhanced appearance with/without solid contrast enhancement. Encasements of major great vessels such as aorta and IVC with/without displacement by metastatic lymphnodes or tumor are frequently seen in 90% of abdominal neuroblastomas. Multiple lymphadenopathy are detected in 95% of abdominal neurobalstomas and 25% of mediastinal neuroblastomas. The most common organ of contiguous direct invasion is kidney in 6 cases and the next one is liver but intraspinal canal invasion is also noted in 2 cases. CONCLUSION: We concluded that diagnosis of neuroblastoma would be easily obtained in masses of pediatric group from recognition of above characteristic findings.
Aorta
;
Diagnosis
;
Kidney
;
Liver
;
Lymphatic Diseases
;
Neuroblastoma*
9.Wilms' tumor:Changes of CT findings after chemotherapy.
Choon Sik YOON ; Myung Jun KIM ; Mi Hae KIM ; Ki Keun OH
Journal of the Korean Radiological Society 1993;29(6):1331-1336
When the tumor is advanced with distant metastasis or unresectable initially, preoperative chemotherapy could be applied in the treatment of Wilms' tumor We experienced 6 cases of favorable type of Wilms' tumor, 1 case of clear cell sarcoma and 1 case of renal cell carcinoma. They were treated with preoperative chemotherapy and underwent CT Scans before and after the therapy. Pathologic changes after chemotherapy in Wilms' tumor were known from previous reports as subtotal hemorrhagic necrosis, cystic change, clusters of foamy histiocytes, granulation tissue formation, primitive nephrogenic tissues and peripherally remained focal areas of blastemal infiltration. Changes of CT findings after chemotherapy were internal necrosis(6/6), decrease in size(5/6), decrease and absence of regional lymph node enlargement(4/6) and improved or disappeared metastatic lesions(3/3). Although our study had some limitations such as small numbers of cases and all cases were favorable types, we thought that there were good correlations between change of CT findings and subtotal hemorrhagic necrosis after preoperative chemotherapy in Wilms' tumor.
Carcinoma, Renal Cell
;
Drug Therapy*
;
Granulation Tissue
;
Histiocytes
;
Lymph Nodes
;
Necrosis
;
Neoplasm Metastasis
;
Sarcoma, Clear Cell
;
Tomography, X-Ray Computed
;
Wilms Tumor
10.Intraventricular Hemorrhage in Full-Term Neonate.
Myoung Bae JEON ; Kook In PARK ; Choon Sik YOON ; Ran NAMGUNG ; Chul LEE ; Dong Gwan HAN
Journal of the Korean Pediatric Society 1994;37(6):776-785
Intraventricular hemorrhage is a common hemorrhagic cerebral disorder in premature, but occurs much less frequently in the full-term newborn. In order to obtain documentation of clinical and ultrasonographic characteristics of intraventricular hemorrhage in full-term, we performed cerebral ultrasonography on 602 newborn infants who had been admitted to neonatal intensive care unit at the Deppartment of Pediatrics, Yonsei University College of Medicine between December 1989 and June 1991. 15 cases (2.5%) of intraventricular hemorrhage were analysed. The results were as follows: 1) Among 15 cases with intraventricular hemorrhage, there was no obstetrical and perinatal complication in 8 cases (53%) and 13 cases (87%) were neurologically normal at birth. 2) Sudden onset of dramatic neurologic abnormalitis inclued seizures, fever, bulging fontanel, irritability, lethargy, vomiting in cases (73%) and the remainder (27%) had no clinical symptoms and signs. 3) The age at diangosis of hemorrhage was before 72 hours in 5 cases (33%), between 4 and 7 days in 2 cases (13%), at 8 to 28 days in 8 cases (53%), 8 of 15 cases (53%) had Grade 1 IVH, four with Grade 2, cases with Grade 3, and 1 case of these infant demonstrated Grade IV IVH. The source of hemorrhage was subependymal germinal matrix in 12 cases (80%) and choroid plaxus in 3 cases (20%). 4) Precipitating factors were cerebral venous infarction in 7 cases, hypoxic injury in 5, and 3 other infants had no identifiable medical risk factors. 5) Among all 15 survivors, 2 of 3 infants with choroid plexus hemorrhage required placement of a ventriculo-peritoneal shunt, in the other case, ventriculomegaly decreased spontaneously.
Choroid
;
Choroid Plexus
;
Hemorrhage*
;
Humans
;
Infant
;
Infant, Newborn*
;
Infarction
;
Intensive Care, Neonatal
;
Lethargy
;
Parturition
;
Pediatrics
;
Precipitating Factors
;
Risk Factors
;
Seizures, Febrile
;
Survivors
;
Ultrasonography
;
Ventriculoperitoneal Shunt
;
Vomiting