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M D Murphey

Publications and source records attributed to M D Murphey.

68 records · Page 4Linked to original sources
PubMed1989

Digital skeletal radiography: spatial resolution requirements for detection of subperiosteal resorption.

Forty direct-magnification (2:1 enlargement) radiographs showing various severities of subperiosteal resorption and 40 normal studies were selected and digitized. Images were processed to produce varying resolution, from 1.42 to 11.4 Ip/mm, corresponding to pixel sizes ranging from 0.04 to 0.32 mm. The conventional and digitized images were evaluated by six radiologists giving their decision confidence on a graded scale. Receiver operating characteristic analyses were performed from these data to compare the digital images with the conventional films. The results show significant improvement in diagnostic accuracy as pixel size decreases to the level of 0.08 mm. Digital images with pixel sizes of 0.04 mm (11.4 Ip/mm) were not significantly different from the magnification radiographs in terms of observer performance. In conclusion, for high-resolution skeletal imaging as needed for detection of subperiosteal resorption, spatial resolution of 5.7 Ip/mm or less resulted in a significant loss of diagnostic accuracy, as compared with conventional films.

Bone Resorption↗
PubMed1989

Diagnostic imaging of spinal trauma.

The radiologist has a pivotal role in evaluation of spinal trauma patients because proper treatment cannot begin before the abnormality is diagnosed. Plain films remain the screening modality of choice, and by understanding the radiographic signs of injury, patterns produced by various traumatic mechanisms can be recognized. As radiologists we can then provide insight to our clinical colleagues into the optimal methods of further investigation. The objective is to eliminate the possibility of further damage and to identify lesions amenable to correction.

Fractures, Bone↗
PubMedDate not supplied

The many faces of osteosarcoma.

Osteosarcoma is the most common primary malignant tumor of bone in adolescents and young adults. It accounts for approximately 15% of all primary bone tumors confirmed at biopsy. There are numerous types of primary osteosarcoma, including intramedullary (high grade, telangiectatic, low grade, small cell, osteosarcomatosis, and gnathic), surface (intracortical, parosteal, periosteal, and high-grade surface), and extraskeletal. Osteosarcoma may also occur as a secondary lesion in association with underlying benign conditions. The identification of osteoid matrix formation and aggressive characteristics usually allows prospective radiologic diagnosis of osteosarcoma. As with all bone tumors, differential diagnosis is best assessed with radiographs, whereas staging is performed with computed tomography or magnetic resonance imaging. Understanding and recognition of the variable appearances of the different varieties of osteosarcoma allow improved patient assessment and are vital for optimal clinical management including diagnosis, biopsy, staging, treatment, and follow-up.

Adolescent↗
PubMedDate not supplied

Enchondroma versus chondrosarcoma in the appendicular skeleton: differentiating features.

Distinction of enchondroma versus intramedullary chondrosarcoma affecting the appendicular skeleton (proximal to the metacarpals and metatarsals) is a frequent diagnostic dilemma. The authors studied a large series of patients with these lesions (92 with enchondromas, 95 with chondrosarcomas) using statistical assessment of both clinical parameters and numerous radiologic manifestations on images from multiple modalities to identify differentiating features. Multiple clinical and imaging parameters demonstrated statistically significant differences between enchondroma and chondrosarcoma, particularly pain related to the lesion, deep endosteal scalloping (greater than two-thirds of cortical thickness), cortical destruction and soft-tissue mass (at computed tomography or magnetic resonance imaging), periosteal reaction (at radiography), and marked uptake of radionuclide (greater than the anterior iliac crest) at bone scintigraphy. All of these features strongly suggested the diagnosis of chondrosarcoma. These criteria allow distinction of appendicular enchondroma and chondrosarcoma in at least 90% of cases.

Adult↗
PubMedDate not supplied

From the archives of the AFIP. Imaging of musculoskeletal neurogenic tumors: radiologic-pathologic correlation.

Numerous neurogenic tumors can affect the musculoskeletal system, including traumatic neuroma, Morton neuroma, neural fibrolipoma, nerve sheath ganglion, neurilemoma, neurofibroma, and malignant peripheral nerve sheath tumors (PNSTs). The diagnosis of neurogenic tumors can be suggested from their imaging appearances, including lesion shape and intrinsic imaging characteristics. It is also important to establish lesion location along a typical nerve distribution (eg, plantar digital nerve in Morton neuroma, median nerve in neural fibrolipoma, large nerve trunk in benign and malignant PNSTs). Traumatic and Morton neuromas are commonly related to an amputation stump or are located in the intermetatarsal space, respectively. Neural fibrolipomas show fat interspersed between nerve fascicles and are often associated with macrodactyly. Nerve sheath ganglion has a cystic appearance and commonly occurs about the knee. Radiologic characteristics of neurilemoma, neurofibroma, and malignant PNST at computed tomography (CT), ultrasonography, and magnetic resonance imaging include fusiform shape, identification of entering and exiting nerve, low attenuation at CT, target sign, fascicular sign, split-fat sign, and associated muscle atrophy. Although differentiation of neurilemoma from neurofibroma and of benign from malignant PNST is problematic, recognition of the radiologic appearances of neurogenic tumors often allows prospective diagnosis and improves clinical management of patients.

Adult↗
PubMedDate not supplied

Imaging of osteochondroma: variants and complications with radiologic-pathologic correlation.

Osteochondroma represents the most common bone tumor and is a developmental lesion rather than a true neoplasm. It constitutes 20%-50% of all benign bone tumors and 10%-15% of all bone tumors. Its radiologic features are often pathognomonic and identically reflect its pathologic appearance. Osteochondromas are composed of cortical and medullary bone with an overlying hyaline cartilage cap and must demonstrate continuity with the underlying parent bone cortex and medullary canal. Osteochondromas may be solitary or multiple, the latter being associated with the autosomal dominant syndrome, hereditary multiple exostoses (HME). Complications associated with osteochondromas are more frequent with HME and include deformity (cosmetic and osseous), fracture, vascular compromise, neurologic sequelae, overlying bursa formation, and malignant transformation. Malignant transformation is seen in 1% of solitary osteochondromas and in 3%-5% of patients with HME. Continued lesion growth and a hyaline cartilage cap greater than 1.5 cm in thickness, after skeletal maturity, suggest malignant transformation. Variants of osteochondroma include subungual exostosis, dysplasia epiphysealis hemimelica, turret and traction exostoses, bizarre parosteal osteochondromatous proliferation, and florid reactive periostitis. Recognition of the radiologic spectrum of appearances of osteochondroma and its variants usually allows prospective diagnosis and differentiation of the numerous potential complications, thus helping guide therapy and improving patient management.

Biopsy↗
PubMedDate not supplied

Imaging of musculoskeletal fibromatosis.

The musculoskeletal fibromatoses comprise a wide range of lesions with a common histopathologic appearance. They can be divided into two major groups: superficial and deep. The superficial fibromatoses are typically small, slow-growing lesions and include palmar fibromatosis, plantar fibromatosis, juvenile aponeurotic fibroma, and infantile digital fibroma. The deep fibromatoses are commonly large, may grow rapidly, and are more aggressive. They include infantile myofibromatosis, fibromatosis colli, extraabdominal desmoid tumor, and aggressive infantile fibromatosis. Radiographs typically reveal a nonspecific soft-tissue mass, and calcification is common only in juvenile aponeurotic fibroma. Advanced imaging (ultrasonography, computed tomography, and magnetic resonance [MR] imaging) demonstrates lesion extent. Involvement of adjacent structures is common, reflecting the infiltrative growth pattern often seen in these lesions. MR imaging may show characteristic features of prominent low to intermediate signal intensity and bands of low signal intensity representing highly collagenized tissue. However, fibromatoses with less collagen and more cellularity may have nonspecific high signal intensity on T2-weighted images. Local recurrence is frequent after surgical resection due to the aggressive lesion growth. It is important for radiologists to recognize the imaging characteristics of musculoskeletal fibromatoses to help guide the often difficult and protracted therapy and management of these lesions.

Diagnosis, Differential↗
PubMedDate not supplied

From the archives of AFIP. Imaging of giant cell tumor and giant cell reparative granuloma of bone: radiologic-pathologic correlation.

The radiologic features of giant cell tumor (GCT) and giant cell reparative granuloma (GCRG) of bone often strongly suggest the diagnosis and reflect their pathologic appearance. At radiography, GCT often demonstrates a metaepiphyseal location with extension to subchondral bone. GCRG has a similar appearance but most commonly affects the mandible, maxilla, hands, or feet. Computed tomography and magnetic resonance (MR) imaging are helpful in staging lesions, particularly in delineating soft-tissue extension. Cystic (secondary aneurysmal bone cyst) components are reported in 14% of GCTs. However, biopsy must be directed at the solid regions, which harbor diagnostic tissue. These solid components demonstrate low to intermediate signal intensity at T2-weighted MR imaging, a feature that can be helpful in diagnosis. Multiple GCTs, although rare, do occur and may be associated with Paget disease. Malignant GCT accounts for 5%-10% of all GCTs and is usually secondary to previous irradiation of benign GCT. Treatment of GCT usually consists of surgical resection. Recurrence is seen in 2%-25% of cases, and imaging is vital for early detection. Recognition of the spectrum of radiologic appearances of GCT and GCRG is important in allowing prospective diagnosis, guiding therapy, and facilitating early detection of recurrence.

Bone Diseases↗
PubMedDate not supplied

Rectus femoris muscle tear appearing as a pseudotumor.

Quadriceps muscle strains are common sporting injuries, but occasionally a tear of the rectus femoris muscle can appear as a soft tissue mass of the anterior thigh with or without a significant history of trauma. Between 1992 and 1996, seven patients were referred to the Orthopaedic Oncology Unit at Walter Reed Army Medical Center with an unexplained soft tissue mass of the thigh. Three were active duty soldiers, three were military dependents, and one was a retired serviceman. All patients were men, and the mean age was 32 years (range, 15 to 73). A palpable, mildly tender mass was confirmed on clinical examination. Laboratory studies and plain radiographs were normal. Magnetic resonance imaging showed an obvious, but often ill-defined, lesion at the musculotendinous junction of the rectus femoris muscle. Four patients subsequently underwent a tissue biopsy to rule out a soft tissue sarcoma. Histologic studies showed fibrosis, degeneration of muscle fibers, and chronic inflammatory cells with no evidence of malignancy. A chronic rectus femoris muscle tear can mimic a soft tissue tumor or sarcoma and needs to be excluded in the differential diagnosis. These tears may occur acutely or may represent an overuse injury caused by repeated microtrauma. Careful history taking, physical examination, and selective radiographic studies, specifically magnetic resonance imaging, can confirm the diagnosis of muscle tear and full functional recovery can be anticipated.

Adolescent↗