Computerized tomography versus nuclear magnetic resonance in acute pancreatitis

The aim of the study was to compare Computed Tomography (CT) and Nuclear Magnetic Resonance (MR) scan's diagnostic reliability in acute pancreatitis (AP). During a 44-month period 21 patients with a clinical and laboratory diagnosis of AP were submitted to CT and MR study. The scans were evaluated according to pancreatitis degree and presence and rate of necrosis. Pancreatitis degree was assessed using Balthazar's grading for CT scans; a similar classification was used for MR scans. Thirteen patients had oedematous pancreatitis and 8 necrotic pancreatitis. Necrosis was diagnosed intraoperatively or in non operated patients with CT scan. MR staging was identical to that of the CT ones except for 2 patients who were grade E at CT and grade D at MR. MR identified necrosis in all 8 patients with necrotic AP whereas CT diagnosed only 5 patients properly since 3 scans were performed without contrast medium infusion because of renal failure. MR proved to be a valid alternative in AP diagnosis: it provide the same diagnostic and prognostic information as CT and does not need contrast infusion, which makes it preferable to CT in the follow-up of severe AP evolution.     

Evaluation of tibial plateau fractures: efficacy of MR imaging compared with CT

OBJECTIVE: CT is often used after plain films to evaluate fractures of the tibial plateau. Because MR imaging can show associated soft-tissue injuries as well as fractures, we hypothesize that MR is superior to CT for imaging these injuries. Accordingly, we compared the efficacy of MR imaging and CT in 22 patients with tibial plateau fractures. SUBJECTS AND METHODS: CT with two-dimensional reconstruction and MR examinations were performed in 22 patients with tibial plateau fractures. The images were interpreted by four radiologists and two orthopedic surgeons. Findings on CT scans and plain films were used to determine the configuration of the fractures and to classify them according to the Schatzker system. This was done with findings on MR images and plain films at a separate session. The MR images were also evaluated for ligamentous and meniscal injuries. A qualitative side-by-side comparison of two-dimensional CT scans and MR images for depiction of fracture configuration was done. Imaging results were correlated with observations from physical examinations in all patients and with surgical findings in 12 patients. RESULTS: All of the six types of fractures of the Schatzker classification were observed in this series. Comparison of two-dimensional CT reconstructions and MR images for depiction of fracture configuration revealed that the two techniques were equal in 14 patients, MR imaging was superior to CT in five patients, and CT was superior to MR imaging in three patients (who had very complex and comminuted fractures). In addition, MR imaging showed 12 complete ligamentous tears and 15 partial ligamentous tears in 15 (68%) of the 22 patients. MR showed meniscal injuries in 12 (55%) of the 22 patients. CONCLUSION: MR imaging was equivalent or superior to two-dimensional CT reconstruction for depiction of fracture configuration in most patients. In addition, MR showed significant soft-tissue injuries. We believe that MR imaging is the preferable imaging technique for most patients with fractures of the tibial plateau.     

Pretherapeutic staging of laryngeal carcinoma. Clinical findings, computed tomography, and magnetic resonance imaging compared with histopathology

BACKGROUND: An accurate pretherapeutic staging of laryngeal carcinoma is required for most treatment planning as well as for evaluation and comparison of the results of different treatment modalities. Neoplastic invasion of the laryngeal cartilage may have important therapeutic implications. To our knowledge, no data are available comparing the impact of endoscopic examination, computed tomography (CT), and magnetic resonance (MR) imaging on pretherapeutic staging accuracy. The purpose of our study was to determine which imaging should be used as an adjunct to other clinical examinations in the pretherapeutic staging of laryngeal carcinoma. METHODS: In this study, 40 consecutive patients with neoplasms of the larynx, who were treated surgically, were included in a prospective pretherapeutic staging protocol that included indirect laryngoscopy, direct microlaryngoscopy, contrast-enhanced CT, and gadolinium-diethylenetriamine pentaacetic acid-enhanced MR imaging at 1.5 Tesla. The surgical specimens were cut in whole-organ slices parallel to the plane of the axial CT and MR images. The histologic findings were compared with the clinical findings including the CT and MR images. The impact of each diagnostic method on pretherapeutic staging was analyzed. RESULTS: Clinical/endoscopic evaluation failed to correctly stage 17 tumors due to invasion of the paraglottic space (1 tumor), preepiglottic space (2 tumors), and extralaryngeal soft tissues (14 tumors), resulting in a pretherapeutic staging accuracy of 57.5%. Neoplastic invasion of cartilage was present in 28 patients and absent in 12 patients. Although MR imaging was more sensitive in detecting neoplastic invasion of cartilage than CT (94% vs. 67%; P = 0.001), MR imaging was less specific than CT (74% vs. 87%; P = 0.007). There was no difference between the overall accuracy of CT and MR imaging in detecting neoplastic invasion of cartilage (80% vs. 82%). The accuracy of combined clinical/endoscopic examination and CT staging was 80% and the accuracy of combined clinical/endoscopic examination and MR imaging staging was 87.5%; the difference was not statistically significant. CONCLUSIONS: Clinical/endoscopic examination alone failed to identify tumor invasion of the laryngeal cartilages and of the extralaryngeal soft tissues, resulting in a low staging accuracy (57.5%). Many pT4 (according to the International Union against Cancer TNM Staging System) tumors were clinically unrecognized. The combination of clinical/endoscopic evaluation and an additional radiologic examination, either CT or MR imaging, resulted in significantly improved staging accuracy (80% vs. 87.5%). MR imaging is significantly more sensitive but less specific than CT in detecting neoplastic cartilage invasion. Therefore, MR imaging tends to overestimate neoplastic cartilage invasion and may result in overtreatment, whereas CT tends to underestimate neoplastic cartilage invasion and may lead to inadequate therapy.     

Magnetic resonance imaging-documented extravasation as an indicator of acute hypertensive intracerebral hemorrhage

OBJECT: The aim of this study was to determine the usefulness of magnetic resonance (MR) imaging-documented extravasation as an indicator of continued hemorrhage in patients with acute hypertensive intracerebral hemorrhage (ICH). METHODS: The authors studied 108 patients with acute hyperintensive ICH. Imaging modalities included noncontrast-enhanced computerized tomography (CT) scanning, gadolinium-enhanced MR imaging, and conventional cerebral angiography obtained within 6 hours after the onset of hemorrhage. A repeated CT scan was obtained within 48 hours to evaluate enlargement of the hematoma. Findings on MR imaging indicating extravasation, including any high-intensity signals on T1-weighted postcontrast images, were observed in 39 patients, and 17 of these also showed evidence of extravasation on cerebral angiography. The presence of extravasation on MR imaging was closely correlated with evidence of hematoma enlargement on follow-up CT scans (p < 0.001). CONCLUSIONS: Evidence of extravasation documented on MR imaging indicates persistent hemorrhage and correlates with enlargement of the hematoma.     

Comparison of radiography, computed tomography and magnetic resonance imaging in the detection of sacroiliitis accompanying ankylosing spondylitis

OBJECTIVE: To compare magnetic resonance (MR) imaging, computed tomography (CT), and radiography in the detection of sacroiliitis accompanying ankylosing spondylitis (AS). DESIGN AND SUBJECTS: Nine volunteers and 24 patients were recruited. Radiography, CT, and MR imaging were completed within a 1-week period in 24 patients with AS. In precontrast MR examination, spin-echo T1, fast spin-echo T2, and gradient echo with rephasing T2* images were obtained without fat saturation using a 0.3-T imager for all volunteers and patients. Postcontrast MR examination was performed using the same precontrast SE T1 sequence for patients with AS. RESULTS AND CONCLUSIONS: MR imaging directly showed the normal cartilage in all 16 sacroiliac joints of the 8 volunteers. In the 24 patients with AS, cartilage abnormalities were observed in 42 sacroiliac joints. More diagnoses of sacroiliitis were made using MR and CT imaging than using radiography (P < 0.001). Therefore, low-field-strength MR can be useful in detecting early sacroiliitis in patients with AS. MR imaging was able to reveal early cartilage changes and bone marrow edema, which could not be found by either CT or radiography.     

MR analysis of lung volume and thoracic dimensions in patients with emphysema before and after lung volume reduction surgery

OBJECTIVE: This study was performed to assess the accuracy of determining lung volume in patients with emphysema using MR imaging and then to investigate changes in thoracic dimensions after lung volume reduction surgery. SUBJECTS AND METHODS: Fast gradient-echo breath-hold MR imaging through the entire thorax at full inspiration and expiration was performed in 21 patients with severe emphysema and was performed again in nine of the patients who underwent surgery. Lung volumes were determined using a semiautomated computerized method of delineating the lungs and summing cross-sectional areas. These summed areas were compared with volumes measured on plethysmography and CT. Postoperative changes in thoracic structure were determined by measuring anteroposterior and transverse lung dimensions and lung height before and after surgery. RESULTS: The correlation coefficients and SEM for determining inspiratory lung volume were MR imaging versus plethysmography, r = .77, SEM = -12% (volume measured as less on MR imaging); CT versus plethysmography, r = .86, SEM = -13% (volume measured as less on CT); and MR imaging versus CT, r = .87, SEM = 4% (volume measured as greater on MR imaging). The correlation coefficients and SEM for determining expiratory volume on MR imaging versus plethysmography were r = .77, SEM = 6% (volume measured as greater on MR imaging). After surgery, decreases were found in all thoracic dimensions, and such decreases were greatest at expiration. CONCLUSION: MR measurements of lung volume are comparable with those of CT and differ from those of plethysmography. Changes in thoracic dimensions after lung volume reduction surgery are consistent with improved respiratory mechanics.     

Neuroimaging findings in patients on immunosuppressive therapy: experience with tacrolimus toxicity

OBJECTIVE: The purpose of this study is to describe the neuroimaging (CT and MR imaging) findings in liver transplant patients who develop severe neurologic side effects during immunosuppressive therapy with tacrolimus and to correlate these findings with clinical signs and tacrolimus levels in blood. SUBJECTS AND METHODS: Brain CT and/or MR imaging was performed on six patients who developed neurologic symptoms while receiving tacrolimus in the post-transplant period. All patients were evaluated by the neurology staff, and imaging studies were independently interpreted by three neuroradiologists. Trough tacrolimus levels in blood were measured with the IMX immunoassay and were correlated with neurologic symptoms and imaging findings. RESULTS: Imaging abnormalities were observed in five of six patients during the course of their neurologic illnesses. For each patient, neurologic symptoms began when the tacrolimus level in blood was at a peak, exceeding the therapeutic limit in all but one case. In five patients, neurologic symptoms eventually resolved after the tacrolimus dose was reduced or after the drug was stopped. Multifocal low attenuation of white matter was the predominant finding seen on CT images, and matching hyperintense white matter foci were observed on long-TR MR images. In three patients, clinical recovery was accompanied by reversal of the white matter abnormalities seen on CT and MR images. CONCLUSION: Immunosuppressive therapy with tacrolimus may produce neurologic side effects that are associated with brain CT and MR imaging abnormalities. Resolution of symptoms and reversal of imaging findings occur when the tacrolimus dose is reduced.     

Hepatocellular carcinoma: CT and MR features after transcatheter arterial embolization and percutaneous ethanol injection

PURPOSE: To investigate the reliability of computed tomography (CT) and magnetic resonance (MR) imaging in the evaluation of the response of hepatocellular carcinoma (HCC) to transcatheter arterial embolization (TAE) followed by percutaneous ethanol injection (PEI). MATERIAL AND METHODS: Between January 1991 and November 1992, 20 patients (15 men and five women, aged 53-73 years [mean, 64.6 years]) with 31 HCC lesions underwent CT and MR imaging before and after treatment with combined TAE and PEI. RESULTS: Twenty-seven tumors, which were hypointense on post-treatment T2-weighted images and on gadolinium-enhanced T1-weighted images, were seen to be necrotic at biopsy. In four cases of incomplete necrosis, viable tumor was hyperintense on T2-weighted images and was enhanced after administration of contrast material. CT provided a larger spectrum of imaging features as a result of the presence of both hyperattenuating areas (caused by retention of iodized oil) and hypoattenuating areas (due to ethanol-induced necrosis). CONCLUSION: CT and MR imaging findings proved useful in the evaluation of the response of HCC to combined TAE and PEI.     

Early advanced hepatocellular carcinoma: evaluation of CT and MR appearance with pathologic correlation

PURPOSE: To determine the computed tomographic (CT) and magnetic resonance (MR) imaging appearances of early advanced hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Twenty-seven surgically resected cases of early advanced HCC were studied with CT, CT during arterial portography, CT arteriography, and MR imaging. RESULTS: The sensitivity of standard CT (unenhanced, early, and late CT combined) for the detection of early advanced HCC was 81%, while that of standard MR imaging (T1- and T2-weighted MR imaging combined) was 83%. A nodule-in-nodule appearance was identified in approximately one-third to one-half of cases. Signal behavior of early and advanced components of early advanced HCC followed the expected behaviors of isolated early HCC and isolated advanced HCC, respectively. Tumor size was accurately estimated with standard CT and standard MR imaging. CONCLUSION: More research must be performed to ascertain whether any relationship exists between the different types of HCC and the clinical outcome.     

Non-squamous cell neoplasms of the larynx: radiologic-pathologic correlation

A variety of benign and malignant non-squamous cell neoplasms may affect the larynx. Most of these uncommon laryngeal neoplasms are located beneath an intact mucosa, making diagnosis difficult with endoscopy alone, and sampling errors may occur if only traditional superficial biopsies are performed. In some laryngeal neoplasms, radiologic evaluation allows the correct diagnosis. Hemangiomas have very high signal intensity at T2-weighted magnetic resonance (MR) imaging and strong enhancement at both computed tomography (CT) and MR imaging after administration of contrast material. Phleboliths, which are pathognomonic for hemangiomas, are easily identified at CT. Chondrogenic tumors typically manifest with coarse or stippled calcifications at CT. Because of their high water content, chondrogenic tumors have very high signal intensity on T2-weighted MR images, whereas only moderate enhancement is observed after administration of contrast material. Lipomas typically manifest at both CT and MR imaging as homogeneous nonenhancing lesions. They are isoattenuating to subcutaneous fat at CT and isointense relative to subcutaneous fat with all MR pulse sequences. Metastases from renal adenocarcinoma typically demonstrate strong contrast enhancement and flow voids at MR imaging, and metastases from melanotic melanoma usually have high signal intensity on T1-weighted MR images and low signal intensity on T2-weighted images owing to the paramagnetic properties of melanin. Although radiologic findings are nonspecific in most other non-squamous cell neoplasms of the larynx (eg, Kaposi sarcoma, hematopoietic tumors, tumors of the minor salivary glands, metastases from amelanotic melanoma), cross-sectional imaging can play an important role in the diagnostic work-up of these unusual tumors by delineating the extent of submucosal tumor spread and directing the endoscopist to the appropriate site for the deep, transmucosal biopsies needed to establish the diagnosis. In addition, CT and MR imaging are crucial for posttherapeutic monitoring and early detection of local recurrence.     

Coats' disease and persistent hyperplastic primary vitreous. Role of MR imaging and CT

Coats' disease is an idiopathic disorder in which telangiectatic and aneurysmal retinal vessels leak a lipoproteinaceous exudate, with consequent bullous retinal detachment. It is a diagnostic challenge, and CT and MR imaging provide valuable information to differentiate it from other pathologies, particularly from retinoblastoma. Typical, advanced Coats' disease shows on CT a denser substance posterior to the vitreous, which on MR is hyperintense on all pulse sequences. Contrast administration on both CT and MR might give slight linear enhancement at the boundary between vitreous and exudation. Persistent hyperplastic primary vitreous (PHPV) is a unilateral disorder in a microphthalmic eye, seen in full-term infants. PHPV rarely is bilateral in patients with Norrie's disease, Warburg syndrome, or patients with retinal dysplasia. Persistent fetal vasculature leads to fibrosis, resulting in elongation of the ciliary processes, retinal detachment, and spontaneous cataracts. The CT appearance in the disorder is quite variable; however, MR imaging may be superior in demonstrating the enhancing retrolental mass and the elongated ciliary processes.     

Unique CT imaging advantages. Hemorrhage and calcification

Computed tomography remains the imaging modality of choice in the detection of two processes: acute intracranial hemorrhage and calcification; however, in the subacute and chronic stages of hemorrhage, MR imaging is more sensitive in aging and staging hemorrhage. FLAIR imaging increases the sensitivity of MR imaging in the detection of subarachnoid hemorrhage. The signal characteristics of calcification on MR imaging is variable, especially on T1-weighted images decreasing its detectability. CT is superior to MR imaging in the detection of calcification. A number of factors including slice thickness, as well as window width and level may affect the detectability of calcification on CT.     

Ovarian cancer: comparison of findings with perfluorocarbon-enhanced MR imaging, In-111-CYT-103 immunoscintigraphy, and CT

PURPOSE: To determine the accuracy of breath-hold gadolinium- and perflubron-enhanced magnetic resonance (MR) imaging, immunoscintigraphy with indium-111-CYT-103 (planar and single photon emission computed tomography [CT]), and contrast material-enhanced CT for the detection of ovarian cancer prior to laparotomy. MATERIALS AND METHODS: Sixteen patients with primary (n = 3) or treated (n = 13) ovarian cancer underwent imaging of the abdomen and pelvis with each modality. All images were reviewed prospectively for tumor location, and results were compared with findings at surgery. RESULTS: With CT or MR imaging, tumor was detected in 11 of 13 (85%) patients compared with 11 of 12 patients (92%) with immunoscintigraphy. Per patient accuracy for CT was 81% compared with 75% for MR imaging and 86% for immunoscintigraphy. For detection of individual sites of tumor, the sensitivity of MR imaging was highest (81%) compared with CT (51%, P < .001) and immunoscintigraphy (50%, P < .01). The combination of MR imaging and immunoscintigraphy depicted 89% of sites of tumor involvement confirmed at laparotomy. CONCLUSION: MR imaging and immunoscintigraphy show promise for the evaluation of patients with ovarian cancer.     

Detection of hepatocellular carcinoma in patients with cirrhosis: MR imaging versus angiographically assisted helical CT

OBJECTIVE: The purpose of our study was to compare the combination of conventional spin-echo, phase-shift gradient-recalled echo (GRE), and triple-phasic dynamic GRE MR imaging with the combination of helical CT hepatic arteriography (CTA) and CT performed during arterial portography (CTAP) in the preoperative detection of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Thirty-seven patients with cirrhosis underwent MR imaging and angiographically assisted CT imaging. Paired T1- and T2-weighted spin-echo images, paired in-phase and out-of-phase GRE images, triple-phasic dynamic GRE images, the combined MR images, and the paired CTA and CTAP images were retrospectively and independently reviewed by three radiologists. Image review was done on a segment-by-segment basis. Of the 280 liver segments, 58 segments contained 79 HCCs that were 0.5-8.0 cm (mean, 2.0 cm) in diameter. The diagnostic value of each pair of images was rated by means of receiver operating characteristic curve analysis. RESULTS: The diagnostic accuracy of combined CTA and CTAP (mean area under the receiver operating characteristic curve [Az] = 0.94) was significantly better than that of spin-echo (Az = 0.86, p < .0001), phase-shift GRE (Az = 0.83, p < .0001), dynamic GRE (Az = 0.85, p < .0001), and all combined (Az = 0.91, p < .001) MR imaging. The relative sensitivity of combined CTA and CTAP (89%) was also significantly (p < .0005) better than that of the combined MR imaging (75%). CONCLUSION: Angiographically assisted helical CT imaging was superior to MR imaging combined with conventional spin-echo, phase-shift GRE, and triple-phasic dynamic GRE techniques in the detection of HCC in patients with cirrhosis. The noninvasive dedicated combined MR imaging could not obviate invasive angiographically assisted CT imaging. Combined CTA and CTAP is recommended, especially in the preoperative examination of patients with HCC.     

Heart rate variability and baroreflex sensitivity in hypertensive subjects with and without metabolic features of insulin resistance syndrome

PURPOSE: The traditional approach to investigating suspected osteomyelitis in children includes conventional radiography and bone scintigraphy. The roles of US, CT and MR imaging are controversial. Our objective was to determine whether the additional use of these modalities would yield information likely to lead to treatment modification. MATERIAL AND METHODS: Sixty-five children with clinically suspected osteomyelitis took part in a prospective study. All patients underwent conventional radiography and bone scintigraphy. In addition to this, US, CT and MR imaging were all performed in 33 patients; the remaining 32 patients were examined with various combinations of these three modalities. The value of the additional information obtained was estimated retrospectively by a pediatric orthopedic surgeon in terms of possible modification of treatment. RESULTS: MR imaging was the modality with the highest sensitivity and specificity for detecting osteomyelitis. MR yielded information likely to influence treatment in the greatest proportion of patients (45%) followed by US (30%). CONCLUSION: The standard investigation protocol with the addition of US (because of its ability to detect subperiosteal abscesses early and simply) is adequate in uncomplicated cases. When additional imaging is required to outline a lesion, or in complicated cases, and when bone scintigraphy is inconclusive, MR imaging should also be performed. CT should be considered when MR investigation is not available or when anesthesia is required but cannot be provided.     

Scorpion toxins and defensins

Advances in CT, MR imaging, and catheter angiography provide the radiologist and neurosurgeon with a variety of imaging options for screening, diagnosis, presurgical evaluation, and postoperative monitoring of patients with intracranial aneurysms. Noninvasive imaging techniques have not replaced conventional angiography for the comprehensive evaluation o aneurysms but are effective in screening patients suspected to have an unruptured aneurysm or for preoperative planning in emergency situations that preclude catheter angiography. CT, CT angiography, MR imaging, and MR angiography can all complement the information obtained with catheter angiography in presurgical planning, and the choice of supplemental studies should be individualized. Rotational and intraoperative angiography are problem-solving options used for selected cases at our institution. Continuous improvements in techniques for CT and MR angiography may someday reach the point where surgery can be undertaken on the basis on noninvasive imaging alone, with catheter angiography reserved for endovascular therapy planning and guidance.     

Value of CT scan and MRI in primary tumors of the ovary

Characterisation of an ovarian mass is of utmost importance in the preoperative evaluation of an ovarian neoplasm. It enables the surgeon to anticipate carcinoma of the ovary before the operation, so that adequate procedures are planned. Although, ultrasonography (US) remains the foremost imaging modality for screening patients with adnexal lesions, computed tomography (CT) recently has proved to be of value in the characterisation and management of tumors of the ovary. Magnetic resonance (MR) imaging has also been shown to have a high degree of diagnostic specificity for certain types of ovarian masses, such as dermoid cysts, and endometriomas. However, the potential of MR imaging to characterize tumors of the ovary has not yet been established. This study assesses the value of MR imaging and CT for the purpose of predicting the malignancy of ovarian lesions, and comparing findings of MR imaging with those of CT.     

Wegener granulomatosis: CT and MR findings

PURPOSE: To demonstrate the spectrum of CT and MR imaging findings in patients with Wegener granulomatosis and to determine how often these findings could be attributed to either direct extension from paranasal or orbital disease sites, remote granulomas, or central nervous system (CNS) vasculitis. METHODS: We retrospectively reviewed the CT or MR studies of 15 patients with Wegener granulomatosis. RESULTS: Abnormal findings were seen in 7 patients (5 examined with MR imaging, 2 with CT). Findings included dural thickening and contrast enhancement (3 patients), infarcts (2 patients), regions of hyperintense signal on T2-weighted MR images (2 patients), and abnormal MR signal in the brain stem (2 patients). Three patients with imaging findings of dural enhancement and thickening were thought to have remote granulomatous lesions involving the dura. No patients had extension from sites external to the CNS or clinical findings suggestive of CNS vasculitis. CONCLUSION: The spectrum of CT and MR findings in Wegener granulomatosis includes dural thickening and enhancements cerebral infarction, and MR signal abnormalities in the brain stem and white matter. Presumed remote granulomatous lesions were the most common causes of CNS findings in this study. Complications related to non-CNS disease (eg, hypertension, endocarditis) also appear to have played a role in some patients.     

Cognitive dysfunction and impaired organization of complex motility in degenerative parkinsonian syndromes

PURPOSE: Our purpose was to present imaging findings of six cases proven or supposed to be von Meyenburg complexes (VMCs) with a basis of reviewing the pathologic literature and to describe imaging points for the diagnosis of typical VMC along with its differential diagnosis. METHOD: Six cases were diagnosed as VMC of the liver with imaging modalities (one had histopathologic proof). Both ultrasound (US) and CT were available for all cases, and MRI was used for three cases. Follow-up with US, CT and/or MRI was performed in five cases. RESULTS: US detected varying abnormalities of the livers in four cases. CT and MRI revealed multiple or numerous intrahepatic tiny (usually < 5 mm) cystoid lesions in all of the cases. The lesions were scattered throughout the livers, and some of them were located more frequently adjacent to the medium-sized portal veins than to the hepatic veins of similar size on CT. Moreover, some lesions were apparently located in the subcapsular areas (up to the hepatic capsules). They were usually irregular in shape and showed no enhancement but increased in number by approximately 80-150% after administration of intravenous contrast medium. The T2-weighted MR images and MR cholangiopancreatography showed the lesions to be much more apparent and to be more numerous than T1-weighted images did. Follow-up of five cases with imaging modalities did not show remarkable change of the lesions. CONCLUSION: Despite our limited experience, VMC lesions seem to show some CT and MR features different from those of other multiple small hepatic lesions. They presented as multiple or numerous intrahepatic tiny cystoid lesions usually with irregular contour, scattered throughout the liver up to the subcapsular areas, and were detected in far greater number by enhanced CT or T2-weighted MR images than by unenhanced CT or T1-weighted images. They showed no remarkable change on long term follow-up imaging. We propose that a diagnosis of typical VMC could be made after analyzing CT or MR images carefully with good understanding of its pathologic basis, but imaging follow-up is necessary in oncology patients.