Imaging features of intraosseous ganglia: a report of 45 cases

The aim of this study is to report the spectrum of imaging findings of intraosseous ganglia (IG) with particular emphasis on the radiographic and magnetic resonance (MR) features. Forty-five patients with a final diagnosis of IG were referred to a specialist orthopaedic oncology service with the presumptive diagnosis of either a primary or secondary bone tumour. The diagnosis was established by histology in 25 cases. In the remainder, the imaging features were considered characteristic and the lesion was stable on follow-up radiographic examination. Radiographs were available for retrospective review in all cases and MR imaging in 29. There was a minor male preponderance with a wide adult age range. Three quarters were found in relation to the weight-bearing long bones of the lower limb, particularly round the knee. On radiographs all were juxta-articular and osteolytic; 74% were eccentric in location, 80% had a sclerotic endosteal margin and 60% of cases showed a degree of trabeculation. Periosteal new bone formation and matrix mineralization were not present. Of the 29 cases that underwent MR imaging, 66% were multiloculated. On T1-weighted images the IG contents were isointense or mildly hypointense in 90% cases. Forty-one per cent of the cases showed a slightly hyperintense rim lining that enhanced with a gadolinium chelate. Thirty-eight per cent were associated with soft tissue extension and 17% with a defect of the adjacent articular cortex. Fifty-five per cent showed surrounding marrow oedema on T2-weighted or STIR images and two cases (7%) a fluid-fluid level prior to any surgical intervention. The authors contend that it is semantics to differentiate between an IG and a degenerate subchondral cyst as, while the initial pathogenesis may vary, the histological endpoint is identical, as are the imaging features apart from the degree of associated degenerative joint disease. IGs, particularly when large, may be mistaken for a bone tumour. Correlation of the typical radiographic and MR imaging features will indicate the correct diagnosis and obviate the need for biopsy.     

Tophaceous gout of the spine: MR imaging features

AIM: To define the magnetic resonance (MR) imaging features of tophaceous gout of the spine. MATERIALS AND METHODS: We present the MR imaging examinations of 4 patients with spinal tophaceous gout. Spin-echo T1-weighted and fast spin-echo T2-weighted images were obtained for all patients, and 2 patients had gadolinium-enhanced MR imaging studies. Corresponding computed tomography (CT) was performed in one patient. All images were evaluated for the characteristics of the gouty tophi. RESULTS: The gouty tophi were located at the lower thoracic (n=1) and lumbar (n=3) levels. All tophi yielded homogeneous intermediate to low signal on T1-weighted images and variable signal intensity on T2-weighted images, comprising small foci of very low signal intensity on all sequences. Gadolinium-enhanced MR imaging studies revealed homogeneous enhancement or heterogeneous peripheral enhancement. Diffuse stippled calcifications were found in the tophi on CT images. Periarticular tophi with juxtaarticular bony erosions around facet joints occurred in 3 patients. CONCLUSION: Spinal tophaceous gout should be considered in the differential diagnosis when periarticular deposits contain very low signal foci on all MR imaging sequences.     

Tophaceous gout of the first costochondral junction in a heart transplant patient

We report the case of a 49-year-old man with a 10-year history of gout, who presented with a painful left first costochondral junction mass. A computed tomography (CT)-guided biopsy of the mass revealed foreign body giant cell reaction and crystalline deposition consistent with tophaceous gout.     

Deposition of intraosseous fat in a degenerating simple bone cyst

A simple bone cyst in the proximal humerus of an 18-year-old man was treated by percutaneous ablation with alcohol irrigation. Subsequent involution of the cyst was associated with fatty replacement within the intraosseous defect. A possible relationship between involuting bone cyst and apparent intraosseous lipoma is discussed.     

Osteomyelitis mimicking a primary bone tumor in a patient with pulmonary arteriovenous malformation and Osler-Weber-Rendu disease

Extremity pain is a common presenting symptom seen by the practitioner; the etiology may be related to problems in the bone, joint, soft tissues, or neurovascular bundle. The differential diagnosis is extensive for each, with a careful history and physical exam narrowing the list. Imaging begins with plain radiographs, reserving CT and MRI for further work-up. We report an unusual presentation of osteomyelitis mimicking a bone tumor in a patient with Osler-Weber-Rendu disease. Electronic Publication     

Inflammatory pseudotumor of the liver in a patient with rectal cancer: a case report

An inflammatory pseudotumor of the liver was discovered during a metastatic examination of a patient with rectal adenocarcinoma. Magnetic resonance imaging showed a three-component lesion that infiltrated a large portal vein, and CT arteriography and CT during arterial portography showed a portal obstruction. A histopathological examination proved that necrosis was present in the central zone; infiltration by proliferating connective tissue with chronic inflammatory cells was prominent in the middle zone; and fibrous changes, including pseudo-bile duct proliferation, were present in the peripheral zone. Magnetic resonance imaging revealed both portal infiltration and histopathological features including the above-noted three components. Magnetic resonance imaging is perhaps the most useful diagnostic modality.     

Isolated or dominant lesions of the patella in gout: a report of seven patients

Isolated or dominant osteolytic lesions of the patella are an unusual manifestation of gout. We present seven patients who had such patellar lesions unilaterally (six patients) or bilaterally (one patient) and analyze the radiologic characteristics to determine whether they can be differentiated from those of other osteolytic lesions of the patella. The lesions were uniformly characterized by a geographic pattern of bone destruction in the superolateral aspect of the patella. Five lesions were each accompanied by a peripatellar soft tissue mass, four of which contained calcification. It therefore appears that an osteolytic lesion of the superolateral portion of the patella, especially when associated with a peripatellar calcified soft tissue mass, should alert one to the possible diagnosis of gout. Awareness of this possibility may obviate the need for invasive diagnostic procedures.     

Multifocal bone tuberculosis presenting as a breast mass: CT and MRI findings

Chest wall involvement is an uncommon manifestation of musculoskeletal tuberculosis. We present computed tomography and magnetic resonance imaging findings in a case with multifocal musculoskeletal tuberculosis presenting as a breast mass. These radiological modalities are not diagnostic without histopathological confirmation, but they are valuable guides to surgery in defining the extent of disease involvement. Received: 1 July 1998; Revision received: 8 October 1998; Accepted: 12 October 1998     

Dynamic breast magnetic resonance imaging without complications in a patient with dual-chamber demand pacemaker

Mammography and ultrasound indicated a cancer of the right breast in a 77-year-old woman with a dual-chamber demand pacemaker. The patient was not pacemaker-dependent. She underwent breast 1.5T magnetic resonance imaging (MRI) (dynamic gradient echo sequence with Gd-DOTA 0.1 mmol/kg). Before the patient entered the MR room, the configuration of the device was changed (the response to magnet was switched from asynchronous to off and the rate-responsive algorithm was disabled). No relevant modifications of heart rhythm or rate were observed during the MR examination. No symptom was reported. Immediately after the examination, the pacemaker interrogation showed neither program changes nor alert warnings. MRI detected a bifocal cancer in the right breast which allowed tailored breast-conserving treatment to be initiated. Histopathology confirmed a bifocal invasive ductal carcinoma.     

Massive ovarian edema mimicking an ovarian neoplasm in a patient with IVC web

Massive ovarian edema is an uncommon benign condition affecting young females predominantly those in the child bearing age group and preadolescent girls. Its clinical and radiologic overlap with ovarian neoplasms and torsion which require surgical intervention makes it imperative for the radiologist to consider this entity preoperatively as preserving fertility is vital in this young age group. We report a case of massive ovarian edema, a rare presentation in a patient with inferior vena cava web and consequent Budd Chiari Syndrome, an association previously unreported in literature.     

CT and MR features of sclerosing mesenteritis mimicking a mesenteric metastasis from the carcinoid tumor

Sclerosing mesenteritis is a rare and benign inflammatory entity characterized by fibrofatty thickening of the mesentery. To our knowledge, there are only a few reports on the features of sclerosing mesenteritis on magnetic resonance (MR) imaging and computed tomography (CT). In this present case, MR imaging demonstrated tissue characterization of fibrosis, and partial maximum intensity projection (MIP) and three-dimensional angiography images obtained using multislice CT clearly revealed the extent of the tumor and the vascular appearance affected by the mass. However, a mesenteric metastasis from the carcinoid tumor may show such imaging features. Therefore, when encountering such a case, we suggest that a tentative diagnosis of sclerosing mesenteritis be made, followed by a biopsy for intraoperative histopathologic analysis to avoid aggressive surgery.     

Desmoplastic fibroma in the thoracic spine: an unusual localization of a rare primary bone tumor

A case of an intraspinal growing desmoplastic fibroma of the thoracic spine (T9–T11) is reported. Desmoplastic fibroma is a rare tumor of connective tissue that shows a locally infiltrative and destructive growth. An affection of the thoracic spine is an extremely rare manifestation. Preoperative CT documents the extent of osseous destruction and tumor associated cortical erosion. In central tumor areas an inhomogeneous, intermediate to low signal is demonstrated by MRI using T1- and T2-weighted spin-echo and turbo-spin-echo sequences. Contrast-enhanced MRI shows marked enhancement in peripheral areas depicting the extraosseous and intramedullary extension. Received: 13 April 2000/Revised: 7 July 2000/Accepted: 10 July 2000     

Diffusion- and perfusion-weighted MR imaging in a patient with acute demyelinating encephalomyelitis (ADEM).

To monitor changes of brain tissue metabolism in acute demyelinating encephalitis (ADEM), we examined a patient with suspected ADEM by serial MRI including diffusion- and perfusion-weighted imaging (DWI, PWI). Within the inflammatory tissue, the apparent diffusion coefficients were reduced, normal, and increased. Perfusion varied between reduced and normal values, except for small hyperperfused regions. Combining standard MRI with DWI and PWI may elucidate different overlapping phases in cerebral inflammation.     

Nonspecific FDG uptake in the tongue mimicking the primary tumor in a patient with cancer of unknown primary

For cancers of the head and neck, the combination of ¹⁸F-fluorodeoxy-glucose positron emission tomography (FDG-PET)/computed tomography (CT) gains wide acceptance, especially if the primary tumor is unknown (CUP).A patient underwent FDG-PET/CT for squamous cell CUP with cervical lymph node metastases. FDG-PET/CT showed uptake in the right side of the tongue, rendering this area a possible location for the primary tumor. However, clinical examination revealed a deviation of the tongue toward the left side indicating affection of the left hypoglossal nerve, causing the increased FDG uptake.This case illustrates the interpretive pitfalls of unspecific FDG uptake in PET/CT imaging of the head and neck.     

Imaging study of ossifying fibroma with associated aneurysmal bone cyst in the paranasal sinus

Objective

To determine the CT and MR imaging features of ossifying fibroma with aneurysmal bone cyst of the paranasal sinus.

Materials and methods

We retrospectively reviewed 15 patients with histopathology-proven ossifying fibromas with aneurysmal bone cysts in the paranasal sinus. All 15 patients underwent CT and MR imaging. The following imaging features were reviewed: location, shape, margin, CT findings, and MR imaging appearances and time-intensity curve of dynamic contrast-enhanced MR imaging.

Results

Ossifying fibromas occurred in the maxillary sinus in one patient, sphenoid sinus in 2, frontal sinus in 3, frontoethmoid sinuses in 3, and ethmoid sinus in 6 patients. Ossifying fibromas showed an elliptic-shape and aneurysmal bone cysts revealed a multicystic appearance, with well-demarcated margins. On unenhanced CT, ossifying fibromas appeared isodense to gray matter with scattered calcifications in nine, ground-glass appearance in 6 patients and aneurysmal bone cysts showed mixed density. Ossifying fibromas appeared isointense to gray matter in 12 and slightly hypointense in three patients on T1-weighted images, and isointense in 4 and hypointense in eleven patients on T2-weighted images, with moderate or marked enhancement after administration of contrast material. The time-intensity curves of eight ossifying fibromas exhibited a rapidly enhancing and rapid washout pattern. The intracystic components of aneurysmal bone cysts showed heterogeneous signal intensity on MR images, with fluid–fluid levels identified clearly by T2-weighted images, without enhancement. The periphery and septa of aneurysmal bone cysts appeared isointense on MR images, with marked enhancement.

Conclusions

Fluid–fluid levels within an elliptic-shape mass with scattered calcifications or ground-glass appearance is highly suggestive of this complicated entity in the paranasal sinus.     

CT and MRI findings in gliomatosis cerebri: a neuroradiologic and neuropathologic review of diffuse infiltrating brain neoplasms

The aim of the study was to develop objective criteria that might be helpful for the diagnosis of gliomatosis cerebri (GC) with the highest possible probability based on both the neuroradiological and histopathological findings. Imaging findings in 14 patients with diffuse infiltrating brain neoplasms were studied by two neuroradiologists. Computed tomography and MRI scans were compared with each other side by side. The extent and kind of disease were graded on a scale of 1–5. Interexamination agreement between the two methods was calculated using a kappa analysis. Neither of the neuroradiologists performed the examinations and both were blinded to the histopathological findings, which were also available for all patients, based on biopsy as well as follow-up CT and MRI studies. A neuroradiological–neuropathological correlation was performed. A score system helped to differentiate the findings in three categories: 1 = suggestive of GC; 2 = GC cannot be excluded; and 3 = others. Both CT and MRI were performed in 14 patients with clinical signs and symptoms of an intracerebral tumor. All examinations had diagnostic quality and showed the involvement of at least two brain lobes. Stereotactic biopsy was carried out in all patients. In 2 patients the neuropathological diagnosis was suggestive of GC, in 1 patient glioblastoma, in 2 patients astrocytoma, and in 5 patients nonspecific astrogliotic proliferation. In the remaining 4 cases anaplastic tumor infiltration was diagnosed. The neuroradiological findings in 5 cases were suggestive of GC; in 6 cases a GC could not excluded; and in 3 patients only a slight probability of GC was found. In 2 cases was the neuropathological and the neuroradiological diagnosis of GC concordant. Magnetic resonance imaging is significantly more sensitive than CT in the diagnosis of GC. However, even with multiple, MRI-guided stereotactic biopsies in correlation with intraoperative analysis of the sample by smear preparations by a neuropathologist the antemortem diagnosis of GC is still difficult. Discussion of neuropathological and neuroradiological findings in each case in combination with a score system may help to resolve discrepancies. Received: 3 March 2000/Revised: 1 August 2000/Accepted: 4 August 2000     

Case report of a tibial fracture in a patient suffering from gout: An atypical site,the importance of differential diagnosis,

We present the case of a 60-year-old man with a history of severe tophaceous gout with polyarticular involvement who came to the emergency room due to direct trauma to the right forearm and knee. The knee X-ray and CT scan showed a lateral tibial plateau fracture characterized by the presence of a lytic bone lesion. The presence of a solid neoplasm was ruled out and a CT-guided biopsy was performed. Histological evaluation revealed findings typical for an advanced intraosseous gout. As there was no significant risk of progression of the lytic lesion, the fracture site was treated conservatively. This case is unique in the literature in terms of location and should be considered as an atypical site of intraosseous gout. Proper differentiation of a pathological fracture on an intraosseous gout location from a neoplastic lesion is essential to choose the correct therapy.     

Unusual high signal intensity on MR images in a patient with multiple tendinous xanthomas

The MR features of a 57-year-old man with multiple tendinous xanthomas are reported. The lesions of the peroneus longus tendons and the Achilles tendons showed diffuse reticulated pattern, which is the typical MR finding of tendinous xanthomas. However, the lesions of the patellar tendons showed no diffuse pattern and contained focal regions of high signal intensity on T 1-weighted images suggesting the deposition of triglycerides. The regions showed high signal intensity on T 2-weighted images and moderate enhancement on contrast-enhanced T 1-weighted images suggesting the presence of associated inflammation. Received: 13 May 1996; Revision received: 19 August 1996; Accepted: 12 September 1996     

MR findings in a patient with Kernicterus

We report on a 2.5-year-old boy with severe mental retardation, choreoathetosis, dystonia, muscle rigidity, opisthotonus and severe hearing impairment. He had history of severe hyperbilirubinaemia immediately after birth presumably due to ABO incompatibility. The history and the clinical picture suggested the diagnosis of Kernicterus. The MR imaging examination upon admission revealed bilateral signal intensity increase in the globus pallidum on T2-weighted sequences. Additionally, our patient showed signal intensity changes within the subthalamic nuclei, which is known to be another characteristic area of bilirubin deposition in Kernicterus. Received: 13 October 1998; Revised: 15 January 1999; Accepted: 12 February 1999     

Intra-articular gouty tophi of the knee: CT and MR imaging in 12 patients

Objective. To define the imaging characteristics of intra-articular tophi of the knee. Design and patients. Twelve patients with intra-articular tophi in the knee were studied with routine MR imaging, gadolinium (Gd)-enhanced MR imaging, and CT over a 4-year period. There were 11 men and one woman, 25–82 years of age (mean age 48 years). Four patients did not have a documented history of gout at the time of the MR examination. The diagnosis of intra-articular tophi was provided by arthroscopy and histological examination (5 patients), by microscopic study of joint fluid (5 patients), or by characteristic clinical, laboratory and imaging findings (2 patients). Results. In 15 MR examinations the tophi were located purely intra-articularly in 10 knees. In the remaining five MR studies, periarticular soft tissues or bone, or both, were involved. All the intra-articular tophi manifested low to intermediate signal intensity on both T1- and T2-weighted images. All five Gd-enhanced MR examinations demonstrated a heterogeneous peripheral enhancement. All 10 CT scans showed varying degrees of stippled calcifications within the tophi. The nature of the calcifications was confirmed on histological examination in three patients. Conclusion. Presenting clinical manifestations of gout may relate to intra-articular tophaceous deposits. Such deposits present as masses on MR images with low to intermediate signal intensity on both T1- and T2-weighted images and a characteristic enhancement pattern following intravenous Gd administration. These features relate primarily to internal calcifications, which are most evident on CT images. MR evaluation (including Gd administration) supplemented, in some cases, with CT scanning allows accurate diagnosis of intra-articular tophaceous deposits. Received: 24 August 1998; Revision requested: 1 October 1998; Revision received: 19 October 1998; Accepted: 23 October 1998