Ultrasonography, computed tomography and magnetic resonance imaging for diagnosis of ovarian carcinoma

Our objective was to compare US, CT, and MR imaging in differentiation of malignant from benign ovarian tumors. Through an electronic literature search and manual review of bibliographies (January 1990 to June 2006), relevant studies on the diagnostic performance of US, CT, and MR imaging in the differentiation between benign and malignant ovarian tumours were identified. Sixty-nine articles were included, yielding 143 studies. Data on the accuracy of the different imaging modalities were analyzed and compared by constructing summary receiver-operating characteristic (ROC) curves. Our results suggest that US techniques seems to be similar with CT and MRI in differentiation of malignant from benign ovarian tumors. The results also revealed that color Doppler flow imaging alone is significantly inferior to combined US techniques, morphologic assessment alone and contrast enhanced US in diagnosis of ovarian cancer. In conclusion, US morphologic assessment still is the most important and common modality in detect ovarian cancer.     

Lissencephaly: diagnosis by computed tomography and magnetic resonance imaging

A patient with Miller-Dieker-Syndrome, which is associated with lissencephaly, was examined by Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). While CT demonstrated the main features of lissencephaly, MRI detected disturbed myelination and cell migration in the cerebral hemispheres and a normal appearance of the cerebellum. MRI provides more accurate information of the pathomorphologic changes of lissencephaly and is thus superior to CT.     

Ultrasonography, computed tomography and magnetic resonance imaging in the assessment of pelvic pathology

OBJECTIVE: Ultrasound (US) is the primary imaging modality in the investigation of pelvic pathology in women however it can be very inaccurate. MRI and CT provide a more detailed pelvic examination and hence we compared their accuracies with that of ultrasound to find out if these two modalities should be used more often. PATIENTS AND METHODS: 136 women who had MRI examination of the pelvis for investigation of probable pelvic pathology were studied. Hundred and twenty-five of these women had an initial ultrasound scan and 23 had an initial CT. Diagnostic accuracy was assessed against histopathology or clinical follow-up. RESULTS: Histopathology was available in 127/136 women. Overall 36% of the lesions were malignant. The overall accuracy of MRI, US and CT were 97%, 77% and 87%, respectively. MRI confidently identified the tissue of origin in 94% compared to only 66% for US. There was a significant difference in accuracy between MRI and US in diagnosing adnexal and uterine pathology. MRI was better than CT and US in diagnosing peritoneal metastases whereas CT was superior in diagnosing omental infiltration. CONCLUSION: We suggest that all women with a pelvic abnormality identified on US or in whom there is a strong clinical suspicion of disease should undergo MR pelvic imaging in preference to CT because of its better soft tissue resolution and multi-planar capability.     

Talocalcaneal coalition: computed tomography and magnetic resonance imaging diagnosis.

A correct evaluation of site and extension of the talocalcaneal coalition inducing biomechanical ankle alterations is very important for planning therapy. Four male patients were submitted to computed tomography (CT) and three of them were also examined by means of magnetic resonance imaging (MRI). In one patient, studied by CT only, a bilateral talocalcaneal coalition was present, while the other three patients, controlled with CT and MRI, were affected by monolateral talocalcaneal coalition which was of osseous type in one case and fibrocartilaginous in two cases. CT and MRI provided detailed information on type and extension of the coalition and both helped in distinguishing between osseous and fibrocartilaginous forms. Only MRI showed an area of subchondral ischemic disease of the posterior subtalar joint in one patient with monolateral fibrocartilaginous talocalcaneal coalition. Compared with CT, MRI proved to be more accurate in evaluation of the talocalcaneal coalition, due to its wider display capability.     

Pancreatitis: computed tomography and magnetic resonance imaging

The value of CT in management of severe acute pancreatitis is well established. Some, but not all, experimental studies suggest a detrimental effect of intravenous iodinated contrast agents in acute pancreatitis, but although initial clinical data tends to support this, the positive advantages of enhanced CT outweigh the possible risks. Magnetic resonance imaging has been shown to be as effective as CT in demonstrating the presence and extent of pancreatic necrosis and fluid collections, and probably superior in indicating the suitability of such collections for percutaneous drainage. Image-guided intervention remains a key approach in the management of severely ill patients, and the indications, techniques and results of radiological intervention are reviewed herein. Both CT and MRI can be used to diagnose advanced chronic pancreatitis, with the recent addition of MRCP as a viable alternative to diagnostic endoscopic retrograde cholangiopancreatography (ERCP). Both MRCP and CT/MR imaging of the pancreatic parenchyma still have limitations in the recognition of the earliest changes of chronic pancreatitis – for which ERCP and tests of pancreatic function remain more sensitive – but the clinical significance of these minor changes remains contentious. Received: 12 February 1998; Revision received: 17 June 1998; Accepted: 22 June 1998     

Syringomyelia: myelography, computed tomography, and magnetic resonance imaging

Seventeen patients with cervical spinal cord cavities were studied with myelography, postmyelographic computed tomography scanning, and magnetic resonance imaging. The three diagnostic techniques were compared for accuracy, patient comfort, and ease of procedure. Magnetic resonance imaging was the best diagnostic and most comfortable procedure. There is no need for myelography or postmyelographic computed tomography scanning for the evaluation of cervical syringomyelia.     

Sacrococcygeal chordoma: magnetic resonance imaging and computed tomography

Magnetic resonance imaging (MRI) was compared to computed tomography (CT) in four cases of sacrococcygeal chordoma. Both techniques yielded important anatomic information and represented important advances over early radiologic imaging methods. MRI provides superior contrast with surrounding soft tissues because of the prolonged T1 and T2 times of the tumors. This was especially important in a case of recurrent chordoma. The direct sagittal images obtained by MRI were valuable in determining the extent of lesions. Either MRI or direct CT coronal images were needed for the demonstration of tumor involving the sacral nerve roots. It was not possible to reliably distinguish between tumor adherent to bowel wall and bowel wall invasion by either technique. It is concluded that MRI is at least equal to CT for demonstration of these lesions and seems likely to become the imaging method of choice.     

Malignant hemangiopericytoma: computed tomography and magnetic resonance imaging

Computed tomography and magnetic resonance imaging of a malignant hemangiopericytoma in a 58-year-old woman are described. The tumor was initially found in the abdomen and resected 34 years ago, but recurred 18 years later, followed by repeated recurrence and eventually metastasis to the lung and then to the liver. The lung nodules were round or oval, homogeneous, and well circumscribed while the massive tumor in the right lobe of the liver was poorly delineated with irregular areas of cystic necrosis. With proper setting of the repetition time and echo delay, the metastatic tumor became distinct from the uninvolved hepatic tissue on magnetic resonance imaging. In this case computed tomography and magnetic resonance imaging were complementary in evaluation of such a tumor.     

Rhabdomyolysis: magnetic resonance imaging and computed tomography findings

OBJECTIVE: Our purpose was to describe the magnetic resonance (MR) imaging and computed tomography (CT) findings in patients with rhabdomyolysis. METHODS: The medical records and imaging studies of 10 patients (5 males, 5 females; age range, 14-60 years; mean age, 28.3 years) with rhabdomyolysis were retrospectively reviewed. Magnetic resonance imaging was available in 9 patients and CT in 2 patients. RESULTS: Two distinct imaging types of rhabdomyolysis were observed. For type 1 rhabdomyolysis (n = 2), the affected muscles revealed homogeneously isointense to hyperintense on T1-weighted, homogeneously hyperintense on T2-weighted and short-tau inversion recovery (STIR) images, and homogeneously enhanced on contrast-enhanced MR images. For type 2 rhabdomyolysis (n = 8), the affected muscles revealed homogeneously or heterogeneously isointense to hyperintense on T1-weighted images, heterogeneously hyperintense on T2-weighted and STIR images, heterogeneously hypodense on CT images, and rim enhanced on contrast-enhanced MR and CT images with the presence of a specific presentation, named as the "stipple sign." CONCLUSIONS: Rhabdomyolysis is a clinical and biochemical syndrome comprising 2 distinct imaging types. Homogeneous signal changes and enhancement in the affected muscles advocate type 1 rhabdomyolysis. The stipple sign is helpful in demonstrating the areas of myonecrosis in type 2 rhabdomyolysis and, together with clinical and laboratory presentations, in reaching the correct diagnosis.     

Bone tumors: magnetic resonance imaging versus computed tomography

The magnetic resonance (MR) imaging characteristics of bone tumors are described and the clinical utility of MR imaging in patient evaluation is reported. Fifty-two patients with skeletal lesions were examined with a Picker MR imager (0.15-T resistive magnet). Twenty-five patients had primary malignancies, seven had benign bone neoplasms, 15 had skeletal metastases, and five had neoplasm simulators. Forty-five patients had CT scans available for comparison. For demonstrating the extent of tumor in marrow, MR was superior to CT in 33% of cases, about equal to CT in 64%, and inferior to CT in 2%. For delineating the extent of tumor in soft tissue, MR was superior to CT in 38% of cases and about equal to CT in 62%. CT was superior in all cases for demonstrating calcific deposits and pathologic fractures. In four patients with metal prostheses or surgical clips, MR was superior to CT in documenting recurrent tumor because of artifactual degradation of the CT image. Direct sagittal and coronal images from MR permit accurate assessment of the relationship of tumor to adjacent normal structures, including the physis, joints, and neurovascular structures. MR is useful in the evaluation of bone tumors: it is of greatest value in evaluations of the peripheral skeleton, the medullary canal, soft tissues, and postoperative tumor recurrence. With a 0.15-T magnet, MR is less useful in the evaluation of the axial skeleton and cortical bone.     

Diagnostic performance of computed tomography and magnetic resonance imaging for detecting peritoneal metastases: systematic review and meta-analysis

Purpose

Primary end point was to assess diagnostic accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) in detecting peritoneal metastases (PM). Secondary end points were determining the diagnostic sensitivity and specificity of CT in detecting PM according to the peritoneal cancer index (PCI), investigating correlations between radiological and surgical PCI, and comparing diagnostic yield of CT versus positron emission tomography (PET)/CT.

Materials and methods

We searched MEDLINE, Cochrane Library, Embase and Web of Science databases. Analytic methods were based on PRISMA. Pooled estimates for sensitivity, specificity, positive and negative likelihood ratios were calculated using fixed and random effect models. I ² was used to evaluate heterogeneity.

Results

Of the 529 articles initially identified, 22 were selected for inclusion (934 patients). Cumulative data for per patient CT diagnostic accuracy were sensitivity 83 % (95 % CI 79–86 %), specificity 86 % (95 % CI 82–89 %), pooled positive LR 4.37 (2.58–7.41), and pooled negative LR 0.20 (0.11–0.35). On a per region basis CT performed best in epigastrium and pelvis. Correlation analysis showed a high correlation between CT-PCI and surgical-PCI scores, ranging from 0.49 to 0.96. MRI and PET/CT achieved similar per patient diagnostic accuracy.

Conclusions

CT should be the preferred diagnostic imaging modality for detecting peritoneal metastases because of the robustness of the data. MRI and PET/CT should be considered second choices, until more consistent information on their diagnostic yield in detecting PM are obtained.

     

Giant spinal arachnoid cysts: computed tomography, magnetic resonance imaging and magnetic resonance myelography correlation

Two cases of giant spinal arachnoid cysts, one of them being symptomatic, are discussed, along with their CT, MRI and MR myelography findings.     

Neurosarcoidosis: evaluation using computed tomography and magnetic resonance imaging

Two patients with unusual central nervous system sarcoid were investigated using computed tomography and magnetic resonance imaging, as well as other x-ray studies. A patient with intramedullary involvement of the spinal cord as well as nerve root involvement was examined. Follow-up examination after treatment with steroids showed a return to normal. The second patient had optic nerve involvement as well as two intracranial parenchymal lesions and granulomatous arachnoiditis. In this patient magnetic resonance imaging offered no advantages over computed tomography in the orbit but was significantly more accurate intracranially.     

Wilson's disease: computed tomography and magnetic resonance imaging findings

The condition of a patient with Wilson's disease was evaluated by magnetic resonance imaging (MRI) on initial presentation of the illness. The examination revealed mild atrophy of the superior vermis. Symmetric areas of increased signal intensity on T2-weighted images were detected in the anterior thalami, mesencephalic tectum and tegmentum. Marked symmetric hypointensities appeared in the head of caudate, pallida, substantia nigra and red nuclei. The histopathology of Wilson's disease suggests that these hypointensities may be secondary to the presence of protein-bound copper.     

Pericardial lipoma: ultrasound, computed tomography and magnetic resonance imaging findings

Primary tumours of the heart and pericardium are extremely rare. Cardiac lipomas account for only 10% of all primary cardiac tumours. A case of surgically proven pericardial lipoma demonstrated by ultrasound, CT and MRI is presented here.     

Characterization of pancreatic adenocarcinoma by magnetic resonance imaging

In the past, magnetic resonance imaging (MRI) of the pancreas has suffered from many technical obstacles that have precluded success, particularly in the evaluation of adenocarcinoma. However, with the improved quality of pancreatic MRI and the use of intravenous gadolinium as a contrast agent, MRI is now proving useful in the evaluation of pancreatic adenocarcinoma. MRI's main role is in accurate preoperative staging when computed tomography and ultrasonography provide equivocal results.     

Angiomyolipoma of the kidney. Comparison between magnetic resonance imaging, computed tomography, and ultrasonography for diagnosis

In six patients with angiomyolipoma of the kidney, five showed a typical pattern in T1, proton and T2 weighted images, with magnetic resonance imaging (MRI). Angiomyolipoma is recognized by its characteristic fatty tissue components, which result in high signal intensity in T1 and proton weighted images and a low signal in T2 weighted images. Five of the patients were also examined with ultrasonography (US); in four of these, the tumor could be recognized by its echodense pattern. Computed tomography (CT) was slightly less sensitive; three out of six examinations failed to produce a definite diagnosis. Instead of the typical low attenuation values of fat, Hounsfield units similar to either muscle or kidney tissue were observed in these 3 cases. In conclusion, the specific diagnosis of angiomyolipoma depends on the amount of fatty tissue present at MRI, CT, and sonography.     

Tyrosinemia: computed tomography, magnetic resonance imaging, diffusion magnetic resonance imaging, and proton spectroscopy findings in the brain

In a 5-month-old boy with tyrosinemia, computed tomography revealed diffuse hypodensity in the centrum semiovale. Magnetic resonance (MR) imaging revealed partial signal differences in the white matter and perirolandic regions, and the posterior limbs of the internal capsules revealed higher signal compared with the remainder of the white matter. There were high-signal changes (restricted water diffusion) in the corresponding regions on images of diffusion-weighted MR imaging (b = 1000 s/mm). This likely represented the presence of intramyelinic edema attributable to status spongiosus. Proton MR spectroscopy (repetition time = 1500 milliseconds, echo time = 40 milliseconds) from the lesion sites revealed 2 separate prominent peaks spread between 3.4 and 3.9 ppm. These peaks could represent the CH and CH2 aliphatic protons of the tyrosine molecule.     

Orbital metastasis: role of magnetic resonance imaging and computed tomography

Imaging of ocular and oral metastasis with CT and MRI is discussed. The relative advantages and disadvantages of the two techniques are presented. MRI seems to be particularly useful in discriminating intraocular tumor from retinal detachment. Both techniques depict orbital lesions well.