Usefulness of T2-weighted Oblique Coronal MR Imaging In Anterior Cruciate Ligament Injury

PURPOSE: To evaluate the usefulness of T2-weighted oblique coronal imaging in the diagnosis of anteriorcruciate ligament (ACL) injury. MATERIALS AND METHODS: The MRI findings of 12 patients with ACL injury and a groupof 12 with normal ACL were respectively reviewed in terms of nonvisualization or focal defect, morphologic changeand increased signal intensity of ACL. Diagnostic accuracy in the conventional sagittal or coronal plane and inthe T2-weighted oblique coronal plane was also compared. T2-weighted oblique coronal scanning was performed, withthe imaging plane parallel to the direction of the intercondylar roof. RESULTS: In the ACL injury group,conventional MR imaging showed nonvisualization or focal defect (10/12), morphologic change (7/12), displacement(4/12), and increased signal intensity (9/12). T2-weighted oblique coronal imaging showed nonvisualization orfocal defect (11/12), morphologic change (5/12), and increased signal intensity(9/12). In the normal ACL group,conventional MR imaging demonstrated false-positive findings, i.e. these mimicked ACL injuries. Nonvisualizationor focal defect (2/12), and morphologic change (1/12), and increased signal intensity (5/12) were seen.T2-weighted oblique coronal imaging demonstrated normal ACL as an anteromedial and posterolateral band ; therewere no false-positive cases. On T2-weighted oblique coronal scan, no normal ACL showed increased signal intersity; compared with conventional MR imaging, this difference was statistically significant(P < 0.005). Overall, thesensitivity, specificity, and accuracy of conventional sagittal or coronal plane and T2-weighted oblique coronalplane imaging were, respectively 92% and 92%, 58% and 100%, and 75% and 96%. CONCLUSION: On T2-weighted obliquecoronal scans, the visualization of all normal anterior cruciate ligaments was better than on conventional MRimages. When ACL injury is vague on conventional MR imaging, T2-weighted oblique coronal imaging is considered tobe useful for the differentiation of ACL injury and normal ACL.

CT Findings of Renal Abscess

PURPOSE: The purpose of this study is to determine characteristic CT findings in renal abscess. MATERIAL AND METHODS: Twenty cases of renal abscess were retrospectively analyzed for CT findings relating to the shape andextent of the abscess, change of nephrogram, peripheral rim enhancment, wedge-shaped enhancement on delayed scans, enlargement of the kidney involved and associated findings. RESULTS: Seven patients had a renal abscess at the right kidney, nine at the left kidney and two bilaterally. The abscesses were round in 18 cases and finger-like in two. Rim enhancement around renal abscess was seen in four cases(20%). Changes in the nephrogram around the abscess were seen in 12 cases(60%). In all six patients who had undergone delayed postcontrast scans, wedge-shaped enhancement was shown around the abscess(100%). In the observation of the extent of renal abscesses, 14 cases were within the kidney, six cases extended the beyond renal capsule, and two were loculated in the renal fascia itself. Renal enlargement was seen in nine cases(45%). CONCLUSION: These results suggest that CT findings such as delayed wedge-shaped enhancement, change of nephrogram, peripheral rim enhancement, renal enlargement, and associated findings are valuable for diagnosis, and that CT also gives information concerning the extent, evolution and complication of a renal abscess.

CT Findings of Endobronchial Tuberculosis (EBTB) in Adults: Comparison with Fiberoptic Bronchoscopy(FOB)

PURPOSE: To evaluate the CT findings of histologically confirmed endobrnchial tuberculosis(EBTB) and to access their diagnostic value by comparing with the bronchoscopic findings. MATERIALS AND METHOD: We evaluated retrospectively the CT findings of 25 patients(male : female=5 : 20) with EBTB, and classified them into 3 types by their characteristic features, which are compared with the brochoscopic findings. The 3 types of CT features were as follows ; type 1 : central mass-like lesion with coarse calcific spots associated with atelectasis, type 2: caseous pneumonia with air-bronchogram associated with atelecatasis, type 3 : irregularly distorted and narrowed bronchovascular changes. RESULTS: Comparing the characteristic CT findings with the bronchoscopic findings, they were as follows ; type 1 showed completely occluded lumen by caseous or scar-like tissue with severely swollenmucosa, type 2 showed very thick tenacious mucous plug with anthracotic pigmentation of mucosa, type 3 showed chronic inflammatory change of mucosa with severely deviated or septated bronchial lumen by out-growing caseousgranulation tissue. A tracheal tuberculosis without parenchymal lesion was noted and the bronchoscopy showed caseous materials along the tracheal lumen to the carinal level. CONCLUSION: The characteristic CT findings ofthe bronchial wall and the changes of the adjacent tissues are related to the tracheobronchial tuberculous involvement. CT is useful for diagnosis of the endobronchial tuberculosis.

Mercuric Chloride-Induced Acute Tubular Necrosis in the Rabbits: Gd-DTPA Enhanced Dynamic IVIR Imaging

PURPOSE: To evaluate potential usefulness of dynamic Gd-DTPA enhanced MRI in the diagnosis of HgCI2 induced acute tubular necrosis of rabbits. MATERIALS AND METHODS: Sixteen rabbits were used as control group, and 14 rabbits and 12 rabbits were used as acute tubular necrosis groups of 24 hours and 48 hours after HgCI2 injection, respectively. Sequential dynamic MR imagings were acquired using Gd-DTPA(0.25mmol/kg), and time-signal intensity curves were obtained from cortex, outer medulla and inner medulla. RESULTS: In control group, a dark band, which reflects concentrated Gd-DTPA, migrated from cortex to inner medulla of the kidney, and the ratio of the signal intensity of post Gd-DTPA injection to the signal intensity of pre Gd-DTPA injection(RSI) decreased below 1 at 13sec and 26sec (mean:17 +/- 6.2sec) in cortex, at 52sec (mean :52sec) in outer medulla, and after 117sec(mean :112 +/- 33.9sec) in inner medulla of the kidney. In acute tubular necrosis group of 24 hours after HgCI2 injection, the dark band did not appear and signal intensity in cortex and medulla increased diffusely, and RSI increased above 1 in all locations. In acute tubular necrosis group of 48 hours after HgCI2 injection, the dark band appeared only in the cortex and no sign of migration was observed, and RSI is little changed except in cortex at 13sec(0.76 +/- 0.05) and 26sec(0.86 +/- 0.06). There were statistically significant differences in the time-RSI curves among cortex, outer medulla, and inner medulla in study groups, respectively (p<0.0001). CONCLUSION: Dynamic Gd-DTPA enhanced MRI of the kidney could be utilized to evaluate both renal structure and functional changes.

Operated DeBakey Type III Dissecting Aortic Aneurysm: Review of 12 cases

PURPOSE: We evaluated the indications of operation and radiologic findings in 12 operated DeBakey type III aortic dissections. MATERIAL AND METHODS: We retrospectively reviewed radiologic findings of 12 operated DeBakey type III aortic dissections, using CT, MRI, or aortography, and correlations were made with clinical course of the patients. RESULTS: Three cases were uncomplicated dissections. There were aneurysm rupture in 4 cases, impending rupture in 4 cases, occlusion of common lilac artery in 2 cases, occlusion of renal artery in 1 case, and compression of bronchus and esophagus by dilated aorta in 1 case. Associated clinical sign and symptoms were chest and back pain in 12 cases, claudication in 3 cases, dyspnea and dysphagia in 1 case, hoarseness in 1 case, and hemoptysis in 1 case. Post-operative complications were death from aneurysm rupture in 1 case, paraplegia in 2 cases, acute renal failure in 3 cases, and hemopericardium in 1 case. CONCLUSION: Although medical therapy is preferred in management of DeBakey type Ill aortic dissection, surgical treatment should be considered in patients with radiological findings of aortic rupture, impending rupture, occlusion of aortic major branches.

Sonographic Findings in Gouty Nephropathy

PURPOSE: Ultrasound(US) findings of hyperechoic renal medulla in gouty nephropathy were compared with clinical features such as serum uric acid level to evaluate its usefulness in determination of the treatment and prognosis. MATERIALS AND METHODS: A retrospective review of US of 36 cases of gouty arthritis was classified into four groups according to the medullary echogenicity (O:normal, grade 1 :renal medulla as isoechoic as renal cortex, grade 2'heterogeneous increased echogenicity of renal medulla than that of renal cortex, grade 3 :the echogenicity of all renal medulla higher than that of renal cortex with renal contour deformity) which were compared with the serum urate level and associated conditions. Nephrocalcinosis and nephrolithiasis were analyzed through the KUB and the RGP. RESULTS: The degree of hyperechoic renal medulla was related to the level of serum uric acid, and in group IV, six cases of obstructive uropathy (nephrocalcinosis and nephrolithiasis) showed deformed renal contour. Associated conditions such as hypertension, alcoholism, diabetes mellitus and drug abuse were distributed in relation to the degree of hyperechoic renal medullas. CONCLUSION: US findings of hyperechoic renal medulla was related with uric acid level in gouty nephropathy and thus could be valuable for treatment decision and prediction of prognosis.

CT findings of craniofacial fibrous dysplasia

Fibrous dysplasia is a benign bony disorder that contains trabeculae of poorly calcified primitive bone formed by osseous metaplasia. It is also characterized by replacement of normal spongiosa by abnormal fibrous tissues. We retrospectively analyzed the computed tomographic (CT) findings of 29 cases with clinically and radiologically diagnosed craniofacial fibrous dysplasia. In 2 cases, only cranial bones were involved and in 7 cases only facial bones were involved. Involvements of both cranial and facial bones were noted in the remained 20 cases. The commonly involved bones in the decreasing order of frequency were as follows: frontal, sphenoidal, ethmoidal and temporal bones in cranium and maxilla, zygoma, lacrimal bones and mandible in facial bones. Even though plain films are enough to diagnose the fibrous dysplasia, we think that CT is useful in more accurate diagnosis by demonstrating amorphous "ground-glass" appearance in the lesion and defining the exact extent of craniofacial fibrous dysplasia.

Angiographic evaluation of arterial injuries in traumatic patients

No abstract available.

An experimental study on MRI signal intensity vs concentration of water-soluble contrast media

No abstract available.

Diagnostic value of computed tomography in pancreatic cancer

This retrospective study was performed to assess CT scan findings of pancratic cancer and its ability todetermine resectability. CT scans of 41 patients, who were diagnosed to have pancreatic cancer on histological orclinical base, were reviewed. Most common findings were; focal pancreatic enlargement, diffuse pancreaticenlargement, loss of distinct contour, peripancretic fat obliteration, bile duct or pancreatic duct dilatation,vascular invasion, lymph node involvement, direct invasion of adjacent organs and distant metastasis.Resectability was assessed according to generally accepted CT findings such as small pancreatic mass lesion havingnormal lobulated contour of pancreas, no evidence of vascular invasion, no evidence lymph node involvement andfree of distant metastasis. With the criteria, 5 cases among 41 cases deemed to be resectable. However onoperation all cases were found unresectable indicating prediction of tumor resectability is difficult even withhelp of CT. Nonetheless CT would be very helpful in management of patients having pancreatic cancer since CT wouldshorten the diagnostic procedures of pancreatic cancer.

The radiological evaluation of pulmonary metastases from gastric carcinoma

Twenty cases of pulmonary metastases from pathologically proven stomach carcinoma were studies with specialreference to the clinico-radiological findings and the grades of cell-differentiation of stomach carcinoma. Theywere calssifed into five types based on the pattern of chest X-ray findings according to the reportedclassifications of metastatic pulmonary carcinoma. The radiological appearance of pulmoanry metastases formstomach carcinoma was didffferent from that of usual pulmonary metastatic cancers. The Type IV metastatic form(Type IV-Progressive increasing interstitial lung markings and then infiltration of pulmonary parenchyme with orwithout evidence of pleural effusion.) was most commonly seen in stomach carcinoma particularly in poorlydifferentiated cell type and more associates with respiratory symptoms than others.

An analysis of the pulmonary lobe using computed tomography

Computed Tomograms of 45 patients with or without lung mass were reviewed to determine the characteristics of the major and minor fissures. Also pulmonary vascular distibutions were analyzed to localize each pulmonary lobe. The results were as follows; 1. Each major fissure area was imaged frequently as lucent band, less frequently dense band. 2. The minor fissure areas were imaged as oval or triangular lucent zones. The oval or triangularlucent zones were as same frequency. 3. Avascular planes without above mentioned lucent zones were also correspond to minor fissure areas. 4. Slices of avascular zones were observated between pulmonary arteries to posterior segment or apicoposterior segment of upper lobe and to superior segement of lower lobe on both lungs.

Computed tomographic evaluation of cerebral disorder in pediatric population

A total of 110 computed tomographic scans of the brain in pediatric population were reviewed. They wereretrospectively analyzed focusing on the ventricular dilatation, widening of subdural space in frontal region andprominence of cerebral sulci in hemisphere. The results were compared with clinical recored. In the measurementbicaudate ventricular index waas above 0.18, which ws considered ventricular dilatation. The subdural space in thefrontal region and teh prominent cerbral sulci in the hemisphere were visualized among the cases aged over twoyears with clinical evidence of cerbral problem is pediatric population. The diagnostic application of CT to thecases of cerebral disorder in pediatric population is highly recommended.

Radiological evaluation about the effects of acute and chronic pancreatitis on the stomach patterns

The present study was intended to examine the spectrum of radiographic patterns of the stomach associated withacute and chronic pancreatitis and their complications. Subjects served for the study consisted of 70 cases ofpancreatitis (36 cases in acute stage and 34 cases in chronic stage). Intramural and perigastic permeation ofextravasated pancreatic enzymes and secondary inflammatory reacation that follows are responsible for theardiographic change observed. 1. Generalized rugal thickening and particularly selective mucosal prominences ingreater curvature of body and antrum are characteristically seen in acute(14 of 36 cases

The relationship of radiological findings and pathological types of primary lung cancer

The present study was intended to define the relationship of radiological findings and pathological types ofprimary lung cancer. The 85 cases were selected after confirmation of the cell types by bronchoscopic biopsy,cervical lymph node or thoracotomy biopsy and lung resection. Results of the study were presented below. 1.Primary lung cancer is frequently developed after 4th decade and males were affected more frequently than femaleswith ratio of 2 to 1. 2. The frequencies of pathologic cell types of lung cancer were presented as follows.Squamous cell carcinoma 40% Adenocarcinoma 25% Undifferentiated cell carcinoma 30% Alveolar cell carcinoma 5% 3.The findings of plain chest radiograph were presented as follows. In squamous cell carcinoma, hilar enlargement orhilar mass is the most frequent finding (53%) with atelectasis(26%) or obstructive pneumonitis(26%). Inadenocarcinoma, pleural effusion is accompained about half of cases (53%). In undifferentiated cell carcinoma,hilar mass with mediastinal widening and pleural effusion is frequent finding.