PURPOSE: To evaluate the frequently of low ahetenuation area in enhanced CT scans of non-Hodgkin lymphoma(NHL) and to find out if there is any pertinent relationship between this and the histopathologic classification. MATERIALS & METHODS: The authors reviewed CT scans in the newly diagnosed 53 patients with NHL. We defined the-low attenuation area as the one with CT attenuation value lower than that of the muscle, surrounding lesion, or other lymph nodes after contrast enhancement. NHL with the low attenuation areas were correlated with the histopathologic findings according to the classification based on the Working Formulation and the frequency of the lesion was evaluated. RESULT: Of the 53 patients, the low attenuation area was found in 13 patients (25%) at CT. The histopathologic classification could be made in 12 patients, among whom one patient was classified as low grade, six as intermediate grade, and five as high-grade. Concerning the specific cell typing, the diffuse large cell type was most common in intermediate-grade NHL seen in five patients and the large cell, immunoblastic type was most common in high-grade NHL seen ih three patients. CONCLUSION: The authors concluded that the low attenution area within lymphoma is not an infrequent finding at CT, and there was no stastistically significant correlation between this finding and the prognostic grading of the Working Formulation.
Classification ; Humans ; Lymph Nodes ; Lymphoma ; Lymphoma, Non-Hodgkin* ; Tomography, X-Ray Computed

PURPOSE: We performed this study to assess the value of CT in the differential diagnosis of palpable neck masses in children. MATERIALS AND METHODS: We retrospectively reviewed the CT scans of the palpable neck masses in 30 children. The masses were proved histopathologically and classified into cystic, solid, and inflammatory mass and their CT findings were analyzed. RESULTS: Twelve cases were cystic masses, 4 were solid masses, and 14 were inflammatory lesions. Cystic masses included cystic lymphangiomas (n=6), branchial cleft cysts (n=3), thyroglossal duct cysts (n=2), and ranula (n=l). Cystic lymphangiomas showed insinuating appearances into adjacent structures and 4 cases occurred in the posterior cervical space. All branchial cleft cysts were round cystic masses with smooth wall and displaced the submandibular gland anteriorly and the sternocleidomastoid muscle posteriorly. Two thyroglossal duct cysts occurred centrally adjacent to the hyoid bone and 1 ranula in the submental area. Solid masses were juvenile hemangioma, pleomorphic adenoma in submandibular gland, neurilemmoma, and fibromatosis colli. Juvenile hemangioma showed well-enhancing mass with indistinct margin and the other solid masses had well-defined margin with their characteristic location. Inflammatory lesions were abscess (n=4), deep neck infections with lymphadenopathy (n=4), submandibular gland inflammation (n=3), and tuberculous lymphadenitis (n=3) and they showed strand-like enhancement in adjacent subcutaneous tissues. Tuberculous lymphadenitis had multiple lymph node enlargement with internal low attenuation areas and showed less surrounding strand-like enhancement than suppurative lymphadenopathies. CONCLUSION: Most neck masses in infants and children were of congenital or inflammatory origin. CT is useful for the evaluation of the child presenting with a neck mass, because it can differentiate various forms of neck masses and is able to reveal the relationship of the masses to the adjacent structures with their characteristic location.
Abscess ; Adenoma, Pleomorphic ; Branchioma ; Child* ; Diagnosis, Differential ; Fibroma ; Hemangioma ; Humans ; Hyoid Bone ; Infant ; Inflammation ; Lymph Nodes ; Lymphangioma, Cystic ; Lymphatic Diseases ; Neck* ; Neurilemmoma ; Ranula ; Retrospective Studies ; Subcutaneous Tissue ; Submandibular Gland ; Thyroglossal Cyst ; Tomography, X-Ray Computed ; Tuberculosis, Lymph Node

PURPOSE: In order to assess the incidence and radiologic findings of herniation pit of the femur neck in Korean. IVlaterials and Methods:In 152 macerated femurs of 88 cadavers, and randomly selected 115 hips of 70 patients, the presence of herniation pit was determi ned by using fluoroscopy and radiography. It was then examined by CT for inspection of overlying surface and its opening was confirmed by inserting thin steal wire under the fluoroscopic guidance. RESULTS: Seventeen herniation pits in 15 macerated femurs of 13 cadavers were noted. (14.8%, 13/88). Two of 13 individuals showed bilaterality. All lesions were found only in males. Six herniation pit in 6 femurs of 6 patients (8.6%, 6/70) were also noted. All lesions were on anterosuperior aspect of. femur neck. Plain radiographs of macerated femurs revealed well marginated and thin sclerosis in 15 lesions. Of all 23 lesions, CTshowed cortical breakdown in 3, and overlying cortical thickening in 8. In 15 macerated femurs, roughed area of cortex was found in anterosuperior aspect of femur in all cases, and tiny openings(diameter less than 1 mm) related to cystic lesions were confirmed in 9 lesions. CONCLUSION: The incidence of herniation pits was 14.8% in 88 cadaver, and 8.6% in 70 patients. All were males.
Cadaver ; Femur Neck* ; Femur* ; Fluoroscopy ; Hip ; Humans ; Incidence* ; Male ; Radiography ; Sclerosis

PURPOSE: To describe the MR findings of simple bone cyst. MATERIALS AND METHODS: We analyzed the signal intensity of the cystic contents, their margins, and internal septae, and the presence of bony fragment and pathologic fracture, and enhancement patterns in MRI of 10 pathologically confirmed simple bone cysts. RESULTS: On MR imaging, the cystic contents were of homogeneously low signal intensity on T1WI and high signal intensity on T2WI in nine cases and fluid-fluid level was seen in one case. The cystic margins were dark in all sequences. There were not any fragment in the cysts. Among the four cases with pathologic fracture, one case had fluid-fluid level and two had some areas of enhancement in the cyst or adjacent soft tissue. All nine cases with gadolinium enhancement showed thin rim enhancement along the inner margin of the cysts and internal septae. CONCLUSION: Homogeneous fluid-like signal intensity of cystic content and thin rim enhancement of margin and internal septae in MR imaging are believed to be helpful in the diagnosis of simple bone cyst.
Bone Cysts* ; Diagnosis ; Fractures, Spontaneous ; Gadolinium ; Magnetic Resonance Imaging

PURPOSE: To understand the MR findings of extraabdominal desmold tumors by correlation with histopathologic findings. MATERIALS AND METHODS: MR images of histologically proved 12 patients with extraabdominal desmold tumor were retrospectively reviewed. Three types of MR features were defined; type I had signal changes on T1 and T2 weighted images and relatively homogeneous nature, type II had homogeneously low signal intensities on T1 and T2 weighted images and type III was a mixed form of type I and type II. Signal intensity, enhancement pattern and margin of the lesions were analyzed on MR images. Pathologic features were analyzed by three aspects, which were cellularity, amount of collagen and vascularity, and were correlated with MR images. RESULTS: The signal intensities of type I desmolds were intermediate on T1 weighted image and higher on T2 weighted image with localized margin and gadolinium enhancement. Pathologically this type showed predominant cellularity and vascularity. The signal intensities of type II desmold were homogenous low signal intensities on both T1 and T2 weighted images without enhancement. Pathologically this type showed predominant collagen components and hypovascularity. Type III desmolds were mixed form of type I and type II on MR images as well as on pathologic features. Type I and type II desmold tumors had localized margins, however type III had both localized and infiltrative margins. CONCLUSION: The MR findings of extraabdominal desmold tumors would reflect the pathologic background of the tumor.
Collagen ; Gadolinium ; Humans ; Retrospective Studies

OBJECTIVE: The purpose of this study was to describe the MR imaging appearance of the dural ligaments which is connected between the anterior dura mater and the posterior longitudinal ligament. MATERIALS AND METHODS: In 10 cadavers with formalin fixation, the dural ligaments were evaluated and photographed after removal of the posterior element of the spinal canal. MR studies of 12 patients who had distinct dural ligaments were evaluated. Spin-echo MR images were obtained on a 1. 5T unit. RESULTS: In seven of the ten cadavers, the midline dural ligament was observed; the lateral dural ligament was observed in 3 cadavers. On MR, the dural ligaments were imaged as thin lines of low signal intensity between the anterior dural margin and the posterior longitudinal ligament. Dural ligaments were well-visualized at the level of the lower lumbar spine which had a more prominent anterior epidural space than that of the upper level of the spine. Eight of 12 cases had well developed midline dural ligaments. Two cases showed distinct lateral dural ligaments and the remaining 2 cases had distinct midline and lateral dural ligaments. CONCLUSION: MR images of the dural ligament demonstrate a thin low signal line at the anterior epidural space.
Cadaver* ; Dura Mater ; Epidural Space ; Formaldehyde ; Humans ; Ligaments ; Longitudinal Ligaments ; Magnetic Resonance Imaging* ; Spinal Canal ; Spine

PURPOSE: To evaluate the optimal pulse sequences in the detection of erosions and for the discrimination of theeffusion from pannus. MATERIALS AND METHODS: MR studies were performed in thirteen patients with clinical diagnosis of rheumatoid arthritis. We used a 1.5T MR unit with single or dual 3 inch coil. We compared coronal images at the same location, obtained with pulse sequences of T2, T2 with fat saturation, and postcontrast T1 with fat suppression. Erosions were assessed by comparing the count of the numbers of erosions depending on each imaging method. A four point scoring systems was used for the comparison of conspicuitof lesion. RESULTS: T2WI with fat suppression and postcontreat T1WI with fat suppresison were better than conventional T2WI in the detection of erosions. The pannus had a heterogeneous signal on T2WI, some of which were enhanced after the intravenous injection of MR contrast a gents. CONCLUSION: We suggest that the fat suppression TIWI with enhacnement or the fat suppression T2WI were better than conventional T2WI for detecting both bone erosion and pannus. The postcontrast MR imaging may often be helpul in distinguishing pannus from the effusion.
Arthritis, Rheumatoid* ; Diagnosis ; Discrimination (Psychology) ; Humans ; Injections, Intravenous ; Magnetic Resonance Imaging* ; Wrist*

PURPOSE: To evaluate MRI findings of malignant ovarian tumors. MATERIALS AND METHODS: MRI findings were retrospectively reviewed in 25 patients with surgically confirmed 30 malignant ovarian tumors(common epithelial tumor;23, sex cord stromal tumor;2, endodermal sinus tumor ; 1, metastatic tumor ;4). The findings evaluated were the lesion size, solid and/or cystic component, wall thickness, septal thickness, necrosis, invasion of adjacent organ, ascites, and adenopathy. RESULTS: MRI findings of the malignant ovarian tumors were as follow:Size of lesion was 5-35cm(mean 14cm) ;solid component was present in 80%(24/30);wall thickness was more than 3ram in 90%(27/30);septal thickness was more than 3ram in 70%(21/30);tumor necrosis was present in 40%(12/30%) ;invasion of adjacent organ was present in 76%(19/25);ascites was present in 56%(14/25);lymphadenopathy was present in 24% (6/25). MRI findings of absence of solid component(6/6), even wall and septal thickness(7/7, 19/19) were found only in epithelial tumors. Uneven septal thickness more than 3mm(7/11) was a predominant MRI findings of non-epithelial tumors. Well-defined cystic lesion within solid component was seen in Krukenberg tumors. CONCLUSION: Evaluation of the lesion size, internal architecture, invasion of adjacent organ, ascites, and lymphadenopathy in MRI would enable diagnosis of malignant ovarian tumors and could lead to possible differential diagnosis of epithelial tumors from non-epithelial tumors.
Ascites ; Diagnosis ; Diagnosis, Differential ; Endodermal Sinus Tumor ; Humans ; Krukenberg Tumor ; Lymphatic Diseases ; Magnetic Resonance Imaging* ; Necrosis ; Retrospective Studies

PURPOSE: The differentiation between renal cell carcinoma(RCC) and transitional cell carcinoma(TCC) is important due to the different methods of treatment and prognosis. But occasionally it is difficult to draw a distinction between the two diseases when renal parenchyme and renal collecting systems are invaded simultaneously. MATERIAL AND METHOD: We reviewed CT scans of 37 cases of renal cell carcinoma and 12 cases of transitional cell carcinoma which showed involvement of renal parenchyma and renal sinus fat on CT. Retrospective analysis was performed by 3 abdominal radiologists. Check points were renalcontour bulging or reniform shape, location of mass center, intact parenchyme overlying the tumor, cystic change, calcification, LN metastasis, vessel invasion, and perirenal extention. RESULT:There were renal contour bulging due to the tumor mass in 33 out of 37 cases of renal cellcarcinima, wherea and nine of 12 cases of transitional cell carcinoma maintained the reniform appearance. This is significant statiscal difference between the two(p<0.005). Center of all TCCs were located in the renal sinus, and 24 out of 35 cases of RCC were located in the cortex(p<0.005). Thirty-six out of 37 cases of RCC lost the overlying parenchyma, whereas 4 out of 9 cases of well enhanced TCC had intact overlying parenchyma(p<0.005) RCC showed uptic change within the tumor mags in 31 cases which was significanity higher than the 4 cases in TCC(p<0.05). CONCLUSION: CT findings of renal cell carcinoma are contour bulging, peripheral location, obliteration of parenchyma, and cystic change. Findings of transitional cell carcinoma are reniform appearance, central location within the kidney, intact overlying parenchyma, and rare cystic change.
Carcinoma, Renal Cell* ; Carcinoma, Transitional Cell* ; Kidney ; Neoplasm Metastasis ; Pelvis* ; Prognosis ; Retrospective Studies ; Tomography, X-Ray Computed

PURPOSE: It may be difficult to differentiate renal cell carcinoma involving collecting system from renal urothelial tumor invading into renal parenchyma. The purpose of this study was to assess the differences of CT findings between two conditions. MATERIALS AND METHODS: CT findings of 5 cases of renal cell carcinoma involving the renal collecting systems and 10 cases of renal urothelial tumors invading the renal parenchyma were compared, and analyzed about the presence or absence of hydronephrosis, normal or abnormal CT nephrogram, renal contour changes due to mass and tentative diagnosis. The diagnoses were confirmed at surgery. RESULTS: Renal cell carcinoma showed hydronephrosis in only 20% and normal CT nephrogram and outward contour bulging in all cases. In contrast, renal urothelial tumor showed hydronephrosis(70%), abnormal CT nephrogram(60%), and preservation of reniform shape(100%). CONCLUSION: Renal contour changes and CT nephrogram may be useful in distinguishing both disease entities.
Carcinoma, Renal Cell* ; Diagnosis ; Hydronephrosis