Proteus syndrome: MRI characteristics of plantar cerebriform hyperplasia

Proteus syndrome is a rare congenital hamartomatous syndrome with a variety of abnormalities. It shares many features with other congenital hamartomatous disorders, but cerebriform hyperplasia of the soles and the palms is known as a quite distinctive characteristic in the dermatologic literature. The purpose of this case report is to demonstrate the MRI features of plantar cerebriform hyperplasia in a 9-year-old boy with known Proteus syndrome. Received: 8 July 1999 Revision requested: 8 September 1999 Revision received: 27 September 1999 Accepted: 8 October 1999     

Premature epiphyseal fusion and degenerative arthritis in chronic recurrent multifocal osteomyelitis

A 9-year-old boy was diagnosed with chronic recurrent multifocal osteomyelitis affecting multiple sites. During an 8-year follow-up he developed premature closure of a distal radial epiphysis and degenerative changes in the adjacent radiocarpal joint. Received: 26 July 1999 Revision requested: 24 August 1999 Revision received: 27 September 1999 Accepted: 8 October 1999     

Sclerotic bone metastases from sarcomatoid renal cell carcinoma

We present a case of sarcomatoid renal cell carcinoma with multiple sclerotic skeletal metastatic lesions. Renal cell carcinoma is frequently metastatic at presentation, with a high incidence of skeletal involvement, classically described as osteolytic. However, sclerotic or osteoblastic metastatic skeletal lesions from renal cell carcinoma are rare, with only two previous reports identified in the literature, neither of which involved the sarcomatoid variant of renal cell carcinoma. In our case the sclerotic metastases were characterized by bone scan, computed tomography (CT), magnetic resonance imaging (MRI), and histologic analysis. Received: 8 April 1999 Revision requested: 27 May 1999 Revision received: 24 June 1999 Accepted: 29 June 1999     

Myxoma of the humerus: an exceptional site of origin

Myxoma of bone, outside of the jaws, is exceptional. We present such a tumor in the humerus and discuss the criteria for the diagnosis of myxoma. Received: 10 August 1999 Revision requested: 10 September 1999 Revision received: 14 September 1999 Accepted: 14 September 1999     

Arthritis and hidradenitis suppurativa diagnosed in a 48-year-old man

We report the case of a 48-year-old man who presented with an erosive, seronegative, HLA-B27-negative, peripheral polyarthritis, associated with hidradenitis suppurativa of axillae and buttocks. The pertinent literature is reviewed. This paper is the second devoted to this topic in a radiological journal and the first to document erosion of the posterior aspect of the calcaneus. Received: 15 September 1998 Revision requested: 28 October 1998 Revision received: 22 February 1999 Accepted: 22 February 1999     

Spontaneous lung herniation after a single cough

Herniation of the lung is commonly caused by congenital rib abnormalities, blunt trauma, or thoracic surgery. Spontaneous hernias are rarely described in the literature. We report a case of a spontaneous intercostal pulmonary hernia following a single cough. In addition, a review of the literature is presented which outlines the classification, causes, and incidence of lung hernias. Some reference is made to possible methods of treatment. Received: 26 March 1999; Revision received: 21 September 1999; Accepted: 27 September 1999     

Rapid chondrolysis after an intra-articular leak of bone cement in treatment of a benign acetabular subchondral cyst: an unusual complication of percutaneous injection of acrylic cement

Percutaneous injection of methylmethacrylate is now increasingly employed to treat bone lesions, both malignant and benign. However, the risks of this procedure are still to be fully established. In this report, we describe a case of rapid chondrolysis appearing after the intra-articular leakage of cement during injection of an acetabular subchondral cyst, resulting in hip replacement. Although the mechanism of such chondrolysis is unknown, this event suggests a chondrolytic effect of the acrylic cement. Thus, it is essential to systematically search for the presence of an intra-articular passage before injecting bone cement into a peri-articular cyst. This unusual complication highlights the need for rigorous evaluation of the benefits and risks of percutaneous injection of acrylic cement in the treatment of benign lesions, especially close to an articulation. Received: 30 September 1999 Revision requested: 1 December 1999 Revision received: 27 December 1999 Accepted: 27 December 1999     

Chondromyxoid fibroma of the acromium with soft tissue extension

Chondromyxoid fibroma is an unusual, benign tumor of cartilaginous origin and represents less than 1% of all primary bone tumors. It usually involves the long bones around the knee joint or the flat bones of the pelvis or ribs. Soft tissue extension is also thought to be rare in these lesions. They are usually eccentrically located in the metaphyses of the long bones and centrally in the flat bones. The radiographic appearances are characteristically those of a single, lytic lesion with lobulated margins, septations, cortical expansion and a sclerotic rim. Histologically, they display a lobulated pattern with spindle-shaped cells lying within a myxoid matrix with areas of hyaline cartilage. The differential diagnosis includes giant cell tumor, chondroblastoma or enchondroma as well as chondrosarcoma. The rarity of these lesions may render the diagnosis difficult to make, especially when the lesion involves an unusual site such as the acromium. Received: 21 June 1999 Revision requested: 27 September 1999 Revision received: 27 October 1999 Accepted: 28 October 1999     

Post-Paget telangiectatic osteosarcoma of the skull

Sarcomatous transformation is the most dreaded complication of Paget’s disease. We report on a case of post-Paget telangiectatic osteosarcoma of the skull, a variant of osteogenic osteosarcoma, in a 79-year-old woman. We discuss the radiological pattern in relationship to the differential diagnosis. Received: 27 July 1998 Revision requested: 24 August 1998, 23 December 1998 Revision received: 25 November 1998, 12 April 1999 Accepted: 13 April 1999     

Intraosseous schwannoma of the metacarpal

Intraosseous schwannoma (neurilemmoma) is an extremely rare, benign neoplasm, constituting less than 0.2% of primary bone tumors. It infrequently involves the bones of the hand. We present a case of intraosseous neurilemmoma of the metacarpal. Received: 26 July 1999 Revision requested: 16 August 1999 Revision received: 16 September 1999 Accepted: 4 October 1999     

Cystic fibrous dysplasia mimicking giant cell tumor: MRI appearance

We report the case of a 43-year-old man who presented with an osteolytic and expansive lesion in the left distal femur mimicking a giant cell tumor. Magnetic resonance imaging (MRI) showed that most of the lesion was cystic, and histological examination revealed fibrous dysplasia with marked cystic degeneration. Radiographic findings of cystic fibrous dysplasia in the end of a long bone may be similar to those of a giant cell tumor, and a biopsy is essential for the final diagnosis. Received: 4 June 1999 Revision requested: 10 August 1999 Revision received: 13 September 1999 Accepted: 15 September 1999     

MR imaging of inflammatory joint diseases of the foot and ankle

Pain affecting the foot and ankle is a common complaint frequently attributable to inflammatory joint diseases. Although conventional radiography is regarded as the initial step in the diagnostic investigation, MR imaging may contribute to further evaluation of these patients due to the direct visualization of the inflammatory soft tissue formed in the disease and its effects on bone, cartilage and para-articular structures. The high spatial resolution of MR imaging combined with tissue characterization often allows initial detection of inflammatory joint abnormalities at a stage that precedes radiographic evaluation. The typical MR appearance of certain inflammatory joint disorders may be helpful in narrowing the wide differential diagnosis. Furthermore, MR imaging can be used for an exact assessment of the extent of the disorder as well as its complications. Accurate diagnostic information can guide the clinician in further diagnostic tests and implementation of proper therapeutic treatment. Received: 12 November 1998 Revision requested: 12 February, 10 June 1999 Revision received: 14 September 1999 Accepted: 20 September 1999     

Progressive destructive vertebral sarcoid leading to surgical fusion

Skeletal sarcoidosis is rare. This report describes a 31-year-old African American man who presented with a destructive osteolytic lesion of C2 and another lesion in a rib. The lesion at C2 was treated with corpectomy and bone graft. Four months later the lesion recurred and a new lesion was discovered in the cervical vertebral column. The patient declined surgery for instability for another 3 months, choosing to remain in a halo. Seven months following the initial operation, a technetium bone scan showed spread of the disease to the calvarium and thoracic and lumbar vertebrae. The patient had no symptoms referable to these sites. The patient agreed to have his neck fused at this point. For the next 10 months, the patient was on steroids and a further new lesion appeared at L5 without localizing signs or symptoms. The patient declined further evaluation over the next 12 months and is now considered lost to follow-up. Received: 29 July 1999 Revision requested: 26 August 1999 Revision received: 1 September 1999 Accepted: 2 September 1999     

Atypical adult non-calcified pilomatricoma

We present a rare case of a non-calcified pilomatricoma in a 67-year-old man. This tumor was extremely large in size, and its location, in the lower extremity, was very unusual. The clinical, radiographic, and histopathological features are described in detail. The role of magnetic resonance imaging (MRI) in the diagnosis of this entity is discussed. Definite internal reticulations and septations were observed. A possible explanation for this observation is that the high signal intensity reticulations may represent edematous stroma surrounding basaloid cells. Received: 8 July 1999 Revision requested: 28 July 1999 Revision received: 10 September 1999 Accepted: 13 September 1999     

Primary hemangiopericytoma of the tibia: MR and angiographic correlation

The Magnetic Resonance Imaging (MRI) appearances of primary osseous hemangiopericytoma (HPC) have been rarely described. We report on a 46-year-old Chinese man with primary osseous HPC of the right tibia. The characteristic vascular distribution of this tumor, presenting with a ”spoke-wheel” appearance on MR images and with angiographic correlation, is described. Although not pathognomonic, this MR appearance may be an important finding in suggesting the diagnosis of osseous HPC. Received: 3 March 1999 Revision requested: 26 April 1999 Revision received: 13 September 1999 Accepted: 15 September 1999     

Chronic ulceration of the leg following extensive scarring due to a snake bite complicated by squamous cell carcinoma

Chronic ulcers of the leg are common in Brazil, perhaps more common than in the developed world. We report a case of a chronic ulcer of the leg following extensive scarring due to a bite by a venomous snake, which eventually led to a squamous cell carcinoma. Received: 16 August 1999 Revision requested: 8 October 1999 Revision received: 10 December 1999 Accepted: 15 December 1999     

The magnetic resonance imaging of musculoskeletal hemorrhage

Hematomas in the extremities can present clinically as a soft tissue mass. Hematomas can usually be distinguished from neoplasia on MR by the signal patterns of hemoglobin breakdown products, which are dependent on the chemical bonding and oxidation state of hemoglobin iron. Beginning with a discussion of relevant atomic electronic structure, this review will examine how oxyhemoglobin, deoxyhemoglobin, methemoglobin, and hemosiderin, the principal iron compounds occurring in the various stages of a hematoma, affect its appearance on MRI. Received: 26 August 1999 Revision requested: 6 October 1999 Revision received: 27 October 1999 Accepted: 27 October 1999     

Retroisthmic cleft: a stress fracture of the lamina

The retroisthmic cleft is a rarely diagnosed defect in the lamina of the lumbar spine. It has always been considered a congenital anomaly. This is the first report we are aware of showing radiological changes in a retroisthmic cleft over a period of time. The follow-up of this patient over a period of 6 years, the radiological and scintigraphic appearances and a review of the literature suggests that the retroisthmic cleft is a stress fracture of the lamina. Received: 9 September 1999 Revision requested: 12 October 1999 Revision received: 1 December 1999 Accepted: 2 December 1999     

Giant ancient schwannoma of the pelvis

A 43-year-old man with a large ancient schwannoma of the pelvis, presenting with varicose veins, is reported. Ancient schwannoma (neurilemmoma) is a benign tumour of nerve sheath origin characterised histologically by features of severe degeneration and which rarely can grow to a large size. Malignant transformation, though reported, is extremely rare. Received: 17 September 1999 Revision requested: 13 October 1999 Revision received: 22 June 2000 Accepted: 28 June 2000     

MRI-induced retrocalcaneal bursitis

This case report describes a patient with acute retrocalcaneal bursitis, which developed after MRI examination of the ankle. The sagittal T2*-weighted gradient echo sequence revealed an extensive susceptibility artifact in the area surrounding the Achilles tendon near its insertion at the os calcis. This artifact was caused by postsurgical metallic particles. We postulate that these particles were mechanically stimulated by the magnetic field and induced the inflammatory response. Received: 20 July 1998 Revision requested: 14 September 1998, 16 March 1999 Revision received: 15 February 1999, 20 May 1999 Accepted: 21 May 1999