Erdheim-Chester disease associated with renal involvement and thrombocythemia

Erdheim-Chester disease is a rare, distinctive lipoidosis characterised by deposition of cholesterol-laden foam cells in the bone marrow associated with a granulomatous reaction affecting the lungs, pericardium, heart and retroperitoneum. A case of Erdheim-Chester disease is presented, with typical skeletal involvement (i. e. diffuse sclerosis of the diaphyses and metaphyses of the long tubular bones) and atypical features including thrombocythemia and renal involvement which was documented on computed tomography. Other features of the reported case include gonadttrophin insufficiency and diabetes insipidus. Correspondence to: M. F. Bellin     

Erdheim-Chester disease: radiographic findings in five patients

We present the case histories of five patients with Erdheim-Chester disease, a rare lipoidosis that has several typical radiographic features. In all the patients, the diaphyses and metaphyses of the extremities demonstrated a symmetric pattern of diffuse or patchy increased density, a coarsened trabecular pattern, medullary sclerosis, and cortical thickening. The epiphyses were spared in four patients and partially involved in one. The axial skeleton was involved in one patient. Radiotracer ^99mTc accumulated in areas of radiographic abnormalities in all patients. In one patient, MRI demonstrated an abnormal signal, corresponding to radiographic abnormalities. The signal was hypointense to muscle on T1-weighted sequences and heterogeneously hyperintense and hypointense to normal bone marrow on T2-weighted sequences. Xanthogranulomatous lesions infiltrated the retroperitoneum in one patient, the testes in one patient, the eyelids in one patient, and the orbits in two patients.     

MR imaging of supra-acetabular insufficiency fractures

 Objective. Diagnosis of insufficiency fractures in the pelvis is difficult, especially in patients with prior malignancy, irradiation, steroid therapy or osteoporosis. This report shows the MR imaging appearance of supra-acetabular insufficiency fractures and how they can be differentiated from metastatic disease. Design and patients. Twelve patients (four men, eight women, average age 72.8 years) at risk for pelvic insufficiency fractures and who had pelvic or hip pain were studied with MR imaging. Indications were possible recurrent tumor or previous radiation to the pelvis (7 patients); osteoporosis from steroid use in rheumatoid arthritis (two patients); to exclude osteonecrosis of the hip (two patients); or to rule out a hip fracture (one patient). Results. A characteristic linear region of low signal intensity on both T1- and T2-weighted sequences was found in the supra-acetabular region paralleling the superior acetabulum in a curvilinear arc in 92% (11/12) of cases, and oblique in origin in 8% (1/11). Diffuse bands of high signal on T2-weighted images indicated surrounding edema. In two cases, MR findings obviated biopsy. One patient underwent a biopsy prior to the imaging studies being reviewed. All patients were treated conservatively and did well. Discussion. Attention to insufficiency fractures has previously focused on characteristic locations in the sacrum and pubic bones. Supra-acetabular insufficiency fractures also occur and are difficult to diagnose without a high degree of suspicion. MR imaging is a useful tool for diagnosing supra-acetabular insufficiency fractures. The characteristic MR imag-ing appearance of these fractures can preclude additional diagnostic studies and therapy in most instances.     

Osseous lesions of the pelvis and long tubular bones containing both fat and fluid-like signal intensity: an analysis of 28 patients

PURPOSE: The purpose of this study was to explore the nature of lesions in the pelvis and the long tubular bones that, with MR imaging, were found to contain both fat and fluid-like signal intensity and to correlate these findings with those of radiography, histologic analysis, and clinical and radiographic follow-up. MATERIALS AND METHODS: A retrospective review of the radiologic, clinical and histologic parameters of 28 patients with lesions in the pelvis and long tubular bones comprised of elements that demonstrated both fat and fluid signal intensity characteristics by MR imaging was performed. Several parameters were analyzed. Histologic analysis was available in 12 patients. Clinical and, or imaging follow-up was available in 13 patients. RESULTS: Imaging and histologic findings suggested the presence of fat and fluid and fluid components in all lesions with which could be divided into distinct MR imaging patterns. Histologic analysis suggested the possibility of a shared pathogenesis among several different lesions. CONCLUSION: All lesions of the long tubular bones in our series revealing both fat and fluid-like signal intensities with MR imaging were nonaggressive on the basis of other imaging findings, follow-up assessment, histologic analysis, or combinations of the three. Histologic findings suggest a relationship among lipomas, fat necrosis and cystic infarct of bone.     

MR findings of Erdheim-Chester disease

Lipoid granulomatosis (Erdheim-Chester disease) is a rare but distinct form of histiocytosis. This disease has characteristic radiologic findings involving the musculoskeletal system that are critical to the diagnosis: symmetric sclerosis of the metaphysis and diaphysis of long bones with relative sparing of the epiphysis as depicted on conventional radiography. However, it is a systemic disease that involves multiple organ systems. This pictorial essay is of a single patient imaged over multiple years, using various pulse sequences with both low and high field strength MR scanners. It depicts many of the characteristic findings encountered in this rare systemic disorder.     

Erdheim-Chester disease

Erdheim-Chester disease (ECD) is characterized by lipid granuloma in the long tubular bones, which leads to pathognomonic symmetrical sclerosis of their metaphyses and diaphyses. Lipid granuloma may also be present in numerous other mesenchymal tissues, especially lung, orbit and retroperitoneal space. The clinical course and prognosis of the disease depend on these lesions. Reviewing 30 cases published since 1931 and a personal case with S100 positive cells, we present the typical radiological and clinical findings. There is striking resemblance to chronic disseminated histiocytosis X.     

Stress fractures of the metatarsal heads

 Objective. To describe the imaging characteristics of stress fractures of the heads of the metatarsal bones, emphasizing their difference from the more common metatarsal shaft and neck stress fractures. Design and patients. Eight patients with stress fractures of the head of one or more of the metatarsal bones were seen in a 5-year period. The four men and four women were 31–72 years of age (mean 52.3 years). Three of the patients were active in sports. Three patients had underlying conditions predisposing to insufficiency fracture and one patient had had a bunionectomy on the affected foot 5 years previously. Plain radiographs and magnetic resonance (MR) imaging studies were reviewed in a retrospective feature. Results. Plain radiographs showed subchondral sclerosis of the metatarsal heads in all but one case, in which MR imaging, performed 6 weeks after the onset of symptoms, demonstrated an area of abnormal signal intensity in the head of the third metatarsal bone consistent with marrow edema. Conclusion. Stress fractures (i.e., fatigue and insufficiency fractures) of the head of the metatarsal bones occasionally occur. Because of their less recognized appearance on routine radiographs and MR images, they are frequently overlooked.     

Cerebral Erdheim-Chester disease: case report and review of the literature

Erdheim-Chester disease is a rare systemic non-Langerhans histiocytosis of unknown etiology that affects multiple organ systems. Cerebral involvement is most often caused by extra-axial masses of foamy histiocytes, whereas intraparenchymal manifestations are less frequent. Review of the literature yielded a total of seven patients with increased signal intensities on T2-weighted images in both dentate nuclei and the peridentate regions. We report on a 44-year-old man with biopsy-proven Erdheim-Chester disease and slowly progressive cerebellar dysfunction. MRI showed additional symmetrical hyperintense signal changes in the superior cerebellar peduncle as well as in the trigonum lemnisci on coronal FLAIR images. The widespread neurological manifestations of cerebral Erdheim-Chester disease and differential diagnosis are discussed.     

Erdheim-Chester disease: clinical and radiological findings

Purpose

The authors retrospectively reviewed six cases of histologically proven Erdheim-Chester disease (ECD) to evaluate organ involvement and clinical and radiological findings.

Materials and methods

Through a search of the pathology databases of four Italian hospitals, we identified six men (mean age, 56 years) with a histological diagnosis of ECD. Histology was performed on retroperitoneal or pulmonary biopsy, depending on disease involvement on imaging. Patients underwent plain radiography of the lower limbs and chest, total-body computed tomography (CT) and bone scintigraphy. Magnetic resonance (MR) imaging was performed in two patients to evaluate the lower limbs and in one patient to study the brain, the chest and the abdomen.

Results

Clinical manifestations included dyspnoea (n=2), hydronephrosis (n=2) and bone pain (n=1). Bilateral symmetrical osteosclerosis of the metaphyseal and diaphyseal portions of the lower-limb long bones was present in five patients. Imaging studies revealed extraskeletal manifestations in all patients, including involvement of the retroperitoneal space (n=4), the lung (n=4) and the heart (n=2).

Conclusions

ECD is a multiorgan disease that displays constant involvement of the bones and retroperitoneum; in particular, of the perirenal fat. Although the diagnosis of ECD is histological, imaging can raise suspicion and help to establish a presumptive diagnosis.     

Scintigraphic findings and follow up in Erdheim-Chester disease

Two cases of Erdheim-Chester disease are presented: a 26-year-old white male patient with lipoidgranulomatosis of numerous long and flat bones and infiltration of pericardium, pleura, liver, spleen, thyroid, skin, conjunctiva, gingiva, and false vocal cord; and a 54-year-old white male with involvement of bones, orbits, brain, pericardium, and retroperitoneum. The scintigraphic findings in this disease are described, and a comprehensive review of the 27 previously reported cases is given including an assessment of the value of scintigraphy for diagnosis and follow up of this rare disease.     

Longitudinal stress fractures of the tibia: diagnosis by magnetic resonance imaging

 Objective. Previous works describe magnetic resonance (MR) imaging characteristics of stress fractures. Diagnosis of the atypical, longitudinal type of stress fracture has been reported using computed tomography (CT). This report focuses on MR imaging of longitudinal stress fractures of the tibia. Materials and methods. Six cases are presented in which a longitudinal linear abnormal marrow signal was detected in the middle and distal parts of the tibial shaft. Five patients were imaged using a 1.5 Tesla MR unit. Axial, sagittal and coronal T1 and T2-weighted or fat suppressed proton density fast spin echo images were obtained in all but one patient. One patient was imaged using a 0.5 Tesla MR unit with axial and coronal T1- and T2-weighted sequences. Initial conventional radiographs seen at clinical presentation were interpreted as normal in all cases. Two patients underwent radionuclide bone scan, and one patient was imaged with CT prior to MR imaging. Results. In each instance, MR imaging demonstrated linear marrow signal abnormalities orientated along the long axis of the tibial shaft. Endosteal and periosteal callus was identified on axial images. In all cases, MR imaging clearly demonstrated a fracture extending through one cortex with abnormal signal in both the marrow cavity as well as adjacent soft tissues indicating edema. Conclusion. MR imaging was shown to be excellent for demonstration of fracture lines, callus, and marrow and soft tissue abnormalities seen in association with longitudinal stress fractures.     

MRI appearance of a primary leiomyosarcoma of bone with epiphyseal involvement

Primary leiomyosarcoma of bone is a rarely reported tumor of elderly subjects. It usually shows an aggressive osteolytic pattern on plain radiographs and involves predominantly the metaphyses of long bones. We report a case of primary leiomyosarcoma of bone, which is atypical by its epiphyseal location, a non-aggressive pattern on plain radiographs and its MR imaging features.     

Malignant fibrous histiocytoma of bone: conventional X-ray and MR imaging features

Objective. To evaluate the conventional X-ray and MR imaging features of malignant fibrous histiocytoma (MFH) of bone. Design. MRI examinations and conventional radiographs were reviewed in 39 patients with biopsy-proven MFH. Imaging characteristics were analyzed and the differential diagnoses assessed in a masked fashion by two experienced radiologists. Results. Typical X-ray features included aggressive, destructive tumor growth centrally located in the metaphysis of long bones. Periosteal reactions and expansive growth were rarely seen. On MR images extraosseous tumor spread was frequently noted. On T2-weighted images and contrast-enhanced T1-weighted images most of the tumors displayed an inhomogeneous, nodular signal pattern with peripheral Gd-DTPA enhancement. Conclusions. Although several MR imaging criteria were typical for MFH none of them was specific. X-ray diagnosis of MFH may also prove difficult, with the main differential diagnosis being metastasis in the older and osteosarcoma in the younger population.     

Bone scintigraphy in Erdheim-Chester disease

Erdheim-Chester disease (ECD) is a rare disorder with fewer than 80 cases reported in the world. It consists of a non-Langerhans' cell histiocytosis that usually presents as pain due to bone involvement; however, the prognosis is marked by extraskeletal involvement. Although the final diagnosis needs an anatomophatologic study (normally through a bone biopsy), radiologic and scintigraphic findings are quasi pathognomonic. In this work, we report 2 ECD cases and their respective bone scans showing typical findings described in the literature. We found bilateral and symmetrical increased uptake of diaphyses and metaphyses of long bones, mainly in lower limbs. The mid-diaphyses and the epiphyses (partially in the first case) as well as the axial skeleton are spared.     

Carpal tunnel syndrome: Staging of median nerve compression by MR imaging

The purpose of this prospective study was to determine the potential of MR imaging to depict morphologic alterations of the median nerve correlating with the stage of carpal tunnel syndrome (CTS). Eighteen wrists of normal subjects and 81 wrists of patients with CTS were examined. MR imaging was performed with proton-density- and T2-weighted spin-echo sequences. Staging of CTS was done on the basis of clinical and electrophysiological testing, including evaluation of the number of previous steroid infiltrations in conservative treatment. Median nerve flattening, cross-sectional area, and signal intensity were measured from the distal radius to the end of the carpal tunnel. Delineation and structure of the median nerve were recorded qualitatively by two experienced radiologists in consensus. Three major MR imaging criteria of early CTS were (a) isolated prestenotic and intracarpal swelling of the median nerve (P < .01), (b) the absence of significant flattening, and (c) a generalized increase in signal intensity retrograde to the distal radius (P < .01). The nerve showed sharply delineated contours and a homogeneous signal pattern. Advanced CTS was characterized by retrograde swelling of the median nerve to the distal radius (P < .01) and decreased signal intensity (P < .05). Demarcation of the nerve became poorer, and its signal pattern appeared fasciculated. After steroid infiltration, the median nerve was difficult to delineate, showed an inhomogeneous structure, and swelling was less pronounced than without steroid infiltration (P < .05). MR imaging yields typical morphologic findings that correlate with the duration and severity of median nerve compression. Hence, MR imaging allows staging of median nerve compression in CTS and thus may contribute to therapeutic decision-making.     

US and MR imaging of peripheral nerves in leprosy

Objective. To analyze peripheral nerves with ultrasonography (US) and magnetic resonance imaging (MR) in leprosy and assess the role of imaging in leprosy patients. Design and patients. Fifty-eight nerves with abnormal clinical features or electromyograms were examined in 23 leprosy patients by means of gray-scale US, Doppler US and MR imaging. Image analysis included: measurement of nerve cross-sectional area; assessment of nerve structure and MR signal intensities; identification of nerve compression within osteofibrous tunnels; detection of endoneural color flow signals and Gd-DTPA enhancement. Correlations were made with clinical findings and a control group of 20 subjects. Fourteen nerves in active reversal reaction were followed up after therapy. Results. Leprosy nerves were classified into three groups based on imaging appearance: group I consisted of 17 normal-appearing nerves; group II, of 30 enlarged nerves with fascicular abnormalities; group III, of 11 nerves with absent fascicular structure. Group II nerves were from patients subjected to reversal reactions; 75% of patients with group III nerves had a history of erythema nodosum leprosum. Nerve compression in osteofibrous tunnels was identified in 33% of group II and 18% of group III nerves. Doppler US and MR imaging were 74% and 92% sensitive in identifying active reactions, based on detection of endoneural color flow signals, long T2 and Gd enhancement. In 64% of cases, follow-up studies showed decreased color flow and Gd uptake after steroids and decompressive surgery. Conclusions. US and MR imaging are able to detect nerves abnormalities in leprosy. Active reversal reactions are indicated by endoneural color flow signals as well as by an increased T2 signal and Gd enhancement. These signs would suggest rapid progression of nerve damage and a poor prognosis unless antireactional treatment is started. Received: 23 August 1999 Revision requested: 18 October 1999 Revision received: 16 November 1999 Accepted: 19 November 1999     

Unusual presentation of Erdheim-Chester disease in a child with acute lymphoblastic leukemia

Erdheim-Chester disease (ECD) is an uncommon, non-familial, non-Langerhans cell histiocytosis, which involves skeletal system and soft tissue usually in middle aged and elderly patients. The characteristic radiologic features include bilateral, symmetric cortical osteosclerosis of the diaphyseal and metaphyseal parts of the long bones, or bilateral symmetrically abnormal intense ^99mTechnetium labelling of the metaphyseal-diaphyseal region of the long bones, and computed tomography scan findings of “coated aorta” or “hairy kidneys”. ECD in childhood with osteolytic lesion is extremely rare. We describe an unusual case with an expansile lytic bone lesion at presentation in a case of acute lymphoblastic leukemia.     

Susceptibility-weighted MR for evaluation of vasodilatory capacity with acetazolamide challenge.

PURPOSETo investigate cerebral vasodilatory capacity by acetazolamide challenge in healthy subjects and in patients with chronic occlusive cerebrovascular disease by using susceptibility-weighted gradient-echo MR imaging.METHODSEight patients with chronic occlusive cerebrovascular disease and four healthy volunteers were studied with susceptibility-weighted MR imaging before and after intravenous administration of 1000 mg of acetazolamide. Signal intensities were measured as a function of time in several regions of interest defined on anatomic images. In all patients with chronic occlusive cerebrovascular disease, acetazolamide challenge and resting regional cerebral blood flow were also evaluated with single-photon emission CT (SPECT).RESULTSIn healthy volunteers, signal intensities began to increase 3 to 4 minutes after acetazolamide administration, with a continuous increase during the subsequent 10 minutes. The effect lasted for approximately 45 minutes after administration. In patients with chronic occlusive cerebrovascular disease, signal changes on susceptibility-weighted MR images of occluded areas with normal vasodilatory capacity on SPECT images did not differ from signal changes of nonocclusive areas. In those patients with changes that reflected diminished vasodilatory capacity, the MR images showed a lower percentage of signal changes after acetazolamide administration than those in normally perfused areas.CONCLUSIONSusceptibility-weighted MR imaging offers an alternative method for estimating vasodilatory capacity.     

Radiation-induced brachial plexopathy: MR imaging

 Objective. To describe the MR imaging appearance of radiation-induced brachial plexopathy. Design. MR imaging was performed in two patients with the clinical diagnosis of radiation-induced brachial plexopathy and in one with surgically proven radiation fibrosis of the brachial plexus. Patients. Three patients who had had radiation therapy to the axilla and supraclavicular region (two with breast carcinoma and one with Hodgkin’s lymphoma) presented with symptoms in the arm and hand. To exclude metastases or tumor recurrence MR imaging was performed. Results and conclusion. In one patient, fibrosis showing low signal intensity was found, while in two patients high signal intensity fibrosis surrounding the brachial plexus was found on the T2-weighted images. In one case gadolinium enhancement of the fibrosis was seen 21 years after radiation therapy. It is concluded that radiation-induced brachial plexopathy can have different MR imaging appearances. We found that radiation fibrosis can have both low or high signal intensities on T2-weighted images, and that fibrosis can enhance even 21 years after radiation therapy.