Multifocal nodular fatty infiltration of the liver mimicking metastatic disease on CT: imaging findings and diagnosis using MR imaging

The aim of this study was to describe the MR appearance of multifocal nodular fatty infiltration of the liver (MNFIL) using T1-weighted in-phase (IP) and opposed-phase (OP) gradient-echo as well as T2-weighted turbo-spin-echo sequences with fat suppression (FSTSE) and without (HASTE). Magnetic resonance imaging examinations at 1.5 T using T1-weighted IP and OP-GRE with fast low angle shot (FLASH) technique, and T2-weighted FSTSE, T2-weighted HASTE of 137 patients undergoing evaluation for focal liver lesions were reviewed. Five patients were identified in whom CT indicated metastatic disease; however, no liver malignancy was finally proven. Diagnosis was confirmed by biopsy (n = 3), additional wedge resection (n = 1) or follow-up MRI 6–12 months later (n = 5). Regarding the identified five patients, the number of focal liver lesions was 2 (n = 2) and more than 20 (n = 3). The MR imaging characteristics were as follows: OP-image: markedly hypointense (n = 5); IP image: isointense (n = 2) or slightly hyperintense (n = 3); T2-weighted FSTSE-image: isointense (n = 5); T2-weighted HASTE image isointense (n = 1); slightly hyperintense (n = 4). On OP images all lesions were sharply demarcated and of almost spherical configuration (n = 5). Further evaluation by histology or follow-up MR imaging did not give evidence of malignancy in any case. Histology revealed fatty infiltration of the liver parenchyma in three patients. Magnetic resonance follow-up showed complete resolution in two patients and no change in three patients. Multifocal nodular fatty infiltration can simulate metastatic disease on both CT and MR imaging. The combination of in-phase (IP) and opposed-phase (OP) gradient-echo imaging can reliably differentiate MNFIL from metastatic disease. Received: 15 September 1999 Revised: 3 February 2000; Accepted: 7 February 2000     

Vertebral sarcoidosis: imaging findings

Sarcoidosis is a multisystemic disease of unknown aetiology characterised by noncaseating granulomatous inflammation with varying presentation and prognosis. Osseous disease reported in 1–13 % of cases commonly involves hands and feet; however, vertebral sarcoidosis is rare. This report describes the radiologic, CT, MRI and radionuclide imaging findings of vertebral involvement of a case with sarcoidosis. Received: 28 January 1999; Revised: 14 April 1999; Accepted: 25 April 1999     

Evaluation of CT findings for diagnosis of pleural effusions

Computed tomography studies are usually used to assess patients with pleural effusions, and radiologists should be aware of the significance of different CT findings for the diagnosis of the effusion. The purpose of this study was to evaluate CT findings for etiological diagnosis of pleural effusions. Contrast-enhanced CT of the chest of 211 patients with pleural effusion of definite diagnosis were evaluated. The CT images were evaluated for the presence and extent of pleural effusion, thickening or nodules, extrapleural fat and other changes in the mediastinum or lung. The CT scans were read by two independent observers and correlation between them was evaluated. Comparison of CT findings between benign and malignant effusions, between exudates and transudates, and between empyemas and the other parapneumonic effusions were carried out. Kappa values for most CT findings were > 0.85. Loculation, pleural thickening, pleural nodules, and extrapleural fat of increased density were only present in exudative effusions. Multiple pleural nodules and nodular pleural thickening were the only pleural findings limited to malignant pleural effusions. The signs were also more frequently seen in empyemas than in other parapneumonic effusions. Computed tomography findings can help to distinguish between transudates and exudates. Although there is some overlap between benign and malignant pleural effusions, pleural nodules and nodular pleural thickening were present almost exclusively in the latter. Although differences between CT findings of empyemas and the other parapneumonic effusions exist, there is no finding which can definitely differentiate between them. Received: 27 January 1999; Revised: 24 June 1999; Accepted: 24 August 1999     

Adnexal torsion: MR imaging findings of viable ovary

We report a case of torsed ovarian cystic tumor, in which contrast-enhanced high-resolution MR images accurately contributed to the diagnosis of torsion despite the lack of symptoms and to the preoperative evaluation of viability of the edematous ovary. Accurate preoperative assessment by MR images and prompt conservative surgical approach succeeded in salvaging the involved ovary. Received: 18 February 2000; Accepted: 27 March 2000     

Gallstone ileus: CT findings

Gallstone ileus is a rare complication of recurrent gallstone cholecystitis. The classic radiographic triad of small bowel obstruction, pneumobilia and ectopic gallstone on abdominal plain radiograph is described with CT imaging. Because of the better resolution of CT compared with abdominal radiography and its recent accession to emergency use, radiologists should be aware of CT findings of gallstone ileus. We report a case in which gallstone ileus was initially diagnosed by CT. Received: 30 July 1999; Revised: 18 October 1999; Accepted: 18 October 1999     

Hepatic endometrioma: a case report and review of the literature

Extrapelvic endometriosis is not uncommon but hepatic endometrioma is extremely rare. Ultrasound, CT and MR features of hepatic endometrioma are discussed and the literature is reviewed in this report. Received: 6 July 1998; Revision received: 4 May 1999; Accepted: 21 June 1999     

Cervical Castleman's disease: imaging findings

Castleman's disease, a lymphoproliferative disease of unknown etiology, rarely causes a neck mass and may mimic granulomatous, inflammatory and metastatic lymph nodes, or lymphoma with its nonspecific imaging findings. Definitive diagnosis and treatment is possible with complete surgical resection. Imaging findings of a case with Castleman's disease detected during multinodular goiter surgery and later verified through excisional biopsy are presented. This report, as far as we know, is the first evaluation of the disease with sonography, Doppler sonography, CT, MR imaging, and digital subtraction angiography (DSA) findings. Received: 31 August 1999; Revised: 30 November 1999; Accepted: 23 December 1999     

Chondromyxoid fibroma of the temporal bone: CT and MRI findings

We present the case of a 44-year-old woman with chondromyxoid fibroma of temporal bone origin. Since this is the least common bone tumor of cartilaginous origin, it is highly unusual to find this tumor in the skull. In fact, the literature describes 18 cases of this form of neoplasia arising in the skull, only 4 of these having originated in the temporal bone. To date, the radiological features of these tumors, and especially features detected using the latest imaging modalities, have not been described in detail. This report is unique in that it is the first to present a case of chondromyxoid fibroma of the temporal bone accompanied by detailed CT and MRI findings. Received: 8 July 1999; Revised: 14 December 1999; Accepted: 20 December 1999     

Littoral cell angioma of the spleen: CT and MR imaging appearance

We report a case of littoral cell angioma (LCA) of the spleen, a recently described splenic pathology, which imaging characteristics and pathologic morphology have been discussed only by a few authors. The imaging findings in unenhanced and contrast-enhanced MRI and CT as well as histologic specimen are presented. Diagnosis was made after elective splenectomy. Differential diagnosis of splenic tumors as well as the imaging findings in this particular case are discussed. Received: 7 July 1999; Revised: 18 January 2000; Accepted: 19 January 2000     

Masses of the tongue and floor of the mouth: findings on magnetic resonance imaging

The purpose of this study was to determine the value of MR imaging for the demonstration of masses in the tongue and floor of the mouth. Nine patients were prospectively examined with MR imaging after physical examination. Imaging protocol included T2 and contrast-enhanced and non-contrast-enhanced T1-weighted turbo spin-echo sequences, and the findings were compared with surgical and histopathological results. Histopathological examination revealed four squamous cell carcinomas, one adenoid cystic carcinoma, two tongue abscesses, and one chronic inflammatory change. The other case was diagnosed as hemangioma depending on clinical and imaging findings alone. In cases with squamous cell carcinoma, staging was done on the basis of MR imaging findings, and was found to be T4 in two cases, T3 in one case, and T2 in another. The primary role of MR imaging of the tongue and oropharynx is not to make a tissue diagnosis. Multiple deep biopsies are mandatory for the differentiation of other inflammatory and neoplastic lesions. Magnetic resonance imaging produces coronal and sagittal image planes to assess the volume and spread of the lesion and helps the surgeon determine the direction in which the biopsy should be performed. Received: 4 October 1999; Revised: 31 January 2000; Accepted: 6 April 2000     

Angiomyolipoma of the liver: ferumoxides-enhanced MR imaging

We report a case of angiomyolipoma of the liver with emphasis on the appearance at MRI after administration of ferumoxides. Post-contrast T1- and T2-weighted images showed a frank decrease of signal intensity in a rim on the margin of the tumor. This unusual finding was related to the presence of an increased number of CD68-positive histiocytic cells in the periphery of the lesion and in the adjacent liver parenchyma. Received: 13 September 1999; Revised: 2 February 2000; Accepted: 3 February 2000     

MR imaging findings in granular cell tumor of the neurohypophysis: a difficult preoperative diagnosis

Granular cell tumor is a rare neoplasm arising within the neurohypophysis. We describe the MR imaging findings in two symptomatic patients. In one patient with history of panhypopituitarism, MR images showed a large sellar and suprasellar mass. The other patient presented with acute loss of vision in her left eye, and MR images showed a suprasellar mass with compression of the optic chiasm. Received: 18 November 1999; Revised: 5 April 2000; Accepted: 10 April 2000     

van der Knaap syndrome: MR imaging findings including FLAIR, diffusion imaging, and proton MR spectroscopy

A patient is reported with diffuse leukoencephalopathy associated with cystic degeneration of the white matter of the brain (van der Knaap syndrome). The changes were studied by fluid attenuated inversion recovery (FLAIR), and diffusion-weighted MR imaging. The FLAIR sequence revealed suppressed signal of the cysts, and widespread high-signal white matter changes associated with thinned cortices. On diffusion-weighted MR imaging, apparent diffusion coefficient (ADC) values ranged from 3.0 × 10^–3 to 2.7 × 10^–3 mm²/s in the temporal cysts, similar to that of CSF. The ADC values within the parenchyma ranged between 2 × 10^–3 and 2.1 × 10^–3 mm²/s, a value falling between normal parenchyma and cerebrospinal fluid, compared with a control group of three healthy subjects. The changes were also evaluated by proton MR spectroscopy, and were compared with a control group of 12 cases. Magnetic resonance spectroscopy revealed apparently increased NAA/Cr ratios in most parts of the brain. The NAA/Cho ratios were either high or low, and the Cho/Cr ratios were increased or normal in different regions. Received: 27 October 1999; Revised: 9 December 1999; Accepted: 20 December 1999     

Abdominal wall hernias: imaging with spiral CT

Computed tomography is an accurate method of identifying the various types of abdominal wall hernias, especially if they are clinically occult, and of distinguishing them from other diseases such as hematomas, abscesses and neoplasia. In this study we examined the CT images of 94 patients affected by abdominal wall hernias observed over a period of 6 years. Computed tomography clearly demonstrates the anatomical site of the hernial sac, the content and any occlusive bowel complications due to incarceration or strangulation. Clinical diagnosis of external hernias is particularly difficult in obese patients or in those with laparotic scars. In these cases abdominal imaging is essential for a correct preoperative diagnosis and to determine the most effective treatment. Received: 20 May 1999; Revised: 10 August 1999; Accepted: 13 August 1999     

Hydro-dynamic CT preoperative staging of gastric cancer: correlation with pathological findings. A prospective study of 107 cases

The aim of this study was to evaluate the accuracy of dynamic CT in the preoperative staging of gastric cancer. One hundred seven patients affected by gastric cancer diagnosed by endoscopic biopsy were prospectively staged by dynamic CT prior to tumor resection. After an oral intake of 400–600 ml of tap water and an intravenous infusion of a hypotonic agent, 200 ml of non-ionic contrast agent were administered by power injector using a biphasic technique. The CT findings were prospectively analyzed and correlated with the pathological findings at surgery. The accuracy of dynamic CT for tumor detection was 80 and 99 % in early and advanced gastric cancer, respectively, with overall detection rate of 96 % (103 of 107). Three early (pT1) and one advanced (pT2) cancers were undetected. Tumor stage as determined by dynamic CT agreed with pathological findings in 83 of 107 patients with an overall accuracy of 78 %. The accuracy of CT in detecting increasing degrees of depth of tumor invasion when compared with pathological TNM staging was 20 % (3 of 15) and 87 % (80 of 92) in early and advanced cancer, respectively. The sensitivity, specificity, and accuracy of CT in the preoperative staging (pT3–pT4 vs pT1–pT2) was 93, 90, and 91.6 %, respectively. The sensitivity, specificity, and accuracy of CT in assessing metastasis to regional lymph nodes was 97.2, 65.7, and 87 %, respectively. Computed tomography correctly staged liver metastases in 105 of 107 patients with an overall sensitivity of 87.5 % and specificity of 99 %. The sensitivity of peritoneal involvement was 30 % when ascites or peritoneal nodules were absent. Our findings show that dynamic CT can play a role in the preoperative definition of gastric cancer stage. The results can be used to optimize the therapeutic strategy for each individual patient prior to surgery, thus avoiding unnecessary intervention and allowing careful planning of extended surgery in eligible patients. Received: 29 June 1999, Revised: 20 October 1999, Accepted: 22 May 2000     

Pulmonary MALT lymphoma: imaging findings in 24 cases

The aim of this study was to describe the imaging features of pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma. The chest radiographs (n = 18) and CT scans (n = 17) of 24 patients (18 men and 6 women) aged 27–78 years (mean = 56 years), with a known diagnosis of pulmonary MALT lymphoma, were retrospectively reviewed by two radiologists and the imaging findings are described. Six of the 24 patients had a history of an autoimmune disorder and 1 patient had acquired immune deficiency syndrome. Multiple pulmonary lesions were identified in 19 of 24 patients (79 %) and solitary lesions in 4 of 24 patients (17 %). Diffuse pulmonary infiltration was present in 1 patient. Lesions included masses or mass-like areas of consolidation (n = 21) and pulmonary nodules (n = 18). Associated findings were air bronchograms, airway dilatation, a positive angiogram sign and a halo of ground-glass shadowing at lesion margins. Peribronchovascular thickening was also observed, as were hilar or mediastinal lymph node enlargement and pleural effusions or thickening. Although rare, the diagnosis of pulmonary MALT lymphoma should be considered in patients with the imaging features described, particularly when in association with an indolent clinical course or a history of autoimmune disease. Received: 4 October 1999; Revised: 24 February 2000; Accepted: 18 April 2000     

Magnetic resonance imaging in the assessment of urologic disease: an all-in-one approach

The aim of this study was to evaluate an “all-in-one” MR procedure to examine the kidneys, the renal vascular supply and renal perfusion, and the urinary tract. In 64 patients (58 with urologic disease and 6 healthy volunteers), MR was performed including: (a) T1- and T2-weighted imaging; (b) 3D contrast-enhanced MR angiography (MRA), including the renal arteries, renal veins, as well as renal perfusion; and (c) 3D contrast-enhanced MR urography (MRU) in the coronal and sagittal plane. For the latter, low- and high-resolution images were compared. Prior to gadolinium injection, 0.1 mg/kg body weight of furosemide was administered intravenously. The results were compared with correlative imaging modalities (ultrasonography, intravenous urography, CT), ureterorenoscopy and/or surgical–pathologic findings. Visualization of the renal parenchyma, the vascular supply, and the collecting system was adequate in all cases, both in nondilated and in dilated systems and irrespective of the renal function. One infiltrating urothelial cancer was missed; there was one false-positive urothelial malignancy. Different MR techniques can be combined to establish an all-in-one imaging modality in the assessment of diseases which affect the kidneys and urinary tracts. Continuous refinement of the applied MR techniques and further improvements in spatial resolution is needed to expand the actual imaging possibilities and to create new tracts and challenges in the MR evaluation of urologic disease. Received: 27 September 1999; Revised: 20 January 2000; Accepted: 22 May 2000     

Ruptured adrenal artery aneurysm: a case report

A case of ruptured adrenal artery aneurysm is presented. The ultrasound, computed tomography and selective renal angiography findings are described in detail. Aneurysms of adrenal arteries are particularly rare. Early diagnosis is important because of their tendency towards rupture and subsequent high mortality rate. Received: 12 November 1998; Revised: 10 March 1999; Accepted: 13 April 1999     

Congenital absence of the horizontal portion of the left portal vein: ultrasound findings

Congenital absence of the horizontal portion of the left portal vein is very rare and has been very reported sporadically. We present three such cases referred from other hospitals with a diagnosis of intrahepatic vascular anomaly. Color Doppler ultrasound not only confirmed the diagnosis but also allowed a quantitative measurement of blood flow in these cases. Although it is a very rare condition, knowledge of the ultrasound and color Doppler findings helps in establishing the diagnosis of this congenital anomaly. Received: 9 July 1999; Revised: 25 October 1999; Accepted: 25 October 1999     

Appendicitis after appendectomy: CT diagnosis

This article presents a case of appendicitis 7 years after open appendectomy. Together with the apparent CT findings we discuss the current literature of this issue. Received: 21 April 1999; Revised: 11 August 1999; Accepted: 13 August 1999