Biomedical subjects

Laura W Bancroft

Publications and source records attributed to Laura W Bancroft.

26 records · Page 2Linked to original sources

PubMed2002

Soft tissue tumors of the lower extremities.

MRI is the preferred modality for th eevaluation of a soft tissue mass following radiography. The radiologic appearance of certain soft tissue tumors or tumor-like processes may be sufficiently unique to allow a strong presumptive radiologic diagnosis. It must be emphasized that one cannot differentiate reliably between benign and malignant lesions on radiologic imaging alone. When a specific diagnosis is not possible, knowledge of tumor prevalence by location and age, with appropriate clinical history and radiologic features, can be used to establish a suitably ordered differential diagnosis.

Adolescent↗

PubMed2002

Primary bone tumors of the lower extremities.

The key to adequate and accurate evaluation, diagnosis, and treatment of bone tumors is an organized and integrated approach involving the surgeon, radiologist, and pathologist. The radiologist plays not only a valuable role in the diagnosis and preoperative staging of bone tumors but may also play a role in biopsy and treatment. Despite the wide variety of imaging modalities available today, radiographs remain the mainstay in the evaluation of osseous neoplasms. Advanced imaging is. however. very useful for staging purposes and for characterization of the internal characteristics of tumors and may aid significantly in limiting the differential diagnosis. Although a detailed discussion of all ofthe various bone tumors of the lower extremities is beyond the scope of this article, an attempt is made to provide a framework for a rational and comprehensive approach to these complicated but relatively uncommon lesions. Certain lesions with unique characteristics are discussed to facilitate the diagnostic process.

Adolescent↗

PubMed2002

Imaging of fatty tumors: distinction of lipoma and well-differentiated liposarcoma.

PURPOSE: To review the reliability of computed tomographic (CT) and magnetic resonance (MR) imaging features in distinguishing lipoma and well-differentiated liposarcoma. MATERIALS AND METHODS: CT (n= 29) and MR (n = 40) images and radiographs (n = 28) of 60 patients with histologically verified fatty tumors (35 lipomas and 25 well-differentiated liposarcomas) were retrospectively reviewed in 31 females and 29 males (mean age, 56 years; age range, 1-88 years). Images were assessed for adipose tissue content, and non-fatty component was classified (thin and/or thick septa and nodular and/or globular components) as absent, mild, moderate, or pronounced. Also assessed were signal intensity and tissue attenuation of the fatty components and non-adipose elements. RESULTS: Statistically significant imaging features favoring a diagnosis of liposarcoma included lesion larger than 10 cm (P <.001), presence of thick septa (P =.001), presence of globular and/or nodular non-adipose areas (P =.003) or masses (P =.001), and lesion less than 75% fat (P <.001). The most statistically significant radiologic predictors of malignancy were male sex, presence of thick septa, and associated non-adipose masses, which increased the likelihood of malignancy by 13-, nine-, and 32-fold, respectively. Both lipoma and liposarcoma demonstrated thin septa and regions of increased signal intensity on fluid-sensitive MR images. CONCLUSION: A significant number of lipomas will have prominent non-adipose areas and will demonstrate an imaging appearance traditionally ascribed to well-differentiated liposarcoma. Features that suggest malignancy include increased patient age, large lesion size, presence of thick septa, presence of nodular and/or globular or non-adipose mass-like areas, and decreased percentage of fat composition.

Adipose Tissue↗

PubMed2002

Wooden foreign bodies: imaging appearance.

OBJECTIVE: The purpose of this study was to identify the characteristic imaging features of wooden foreign bodies. MATERIALS AND METHODS: The imaging studies of 12 patients with surgically confirmed wooden foreign bodies were retrospectively reviewed. The study group consisted of seven females and five males, 10-65 years old (mean age, 36 years). All patients underwent radiography. Nine patients were evaluated with sonography, eight with MR imaging, three with CT, and one with CT arthrography. Gadolinium-enhanced MR imaging was performed in six patients. Three patients presented with a draining sinus and nine with painful swelling. Only three patients presented with a history of penetrating injury. RESULTS: Lesions were located in the foot (n = 4), hand (n = 3), thigh (n = 2), calf (n = 2), and elbow (n = 1). Radiographs failed to reveal the retained foreign bodies in all patients. With MR imaging, wooden foreign bodies displayed a variable signal intensity that was equal to or less than that of skeletal muscle on both T1- and T2-weighted images. MR imaging showed the surrounding inflammatory response in all patients. CT showed the retained wood as linear cylindric foci of increased attenuation. Wood was highly echogenic and revealed pronounced acoustic shadowing on sonography. Arthrography in one patient showed an associated reactive synovitis. CONCLUSION: The imaging appearance of wooden foreign bodies is variable; however, imaging can be quite specific, and when taken in the appropriate clinical setting, the imaging should reliably suggest the diagnosis. Sonography is frequently underused but proved most useful for the evaluation of retained wooden foreign bodies.

Adolescent↗

PubMed2002

Intramuscular myxoma: characteristic MR imaging features.

OBJECTIVE: The purpose of our study was to identify the characteristic MR imaging features of intramuscular myxoma. MATERIALS AND MATERIALS: We retrospectively reviewed the MR imaging features of 20 patients with intramuscular myxoma. Clinical assessment included the age and sex of the patient and location of the tumor. Radiologic evaluation included the lesion size and shape, border definition, signal on T1- and T2-weighted or fluid-sensitive MR sequences, enhancement pattern, presence or absence of a fat rind, and presence or absence of increased signal in the adjacent muscle on T2-weighted or fluid-sensitive MR sequences. RESULTS: The mean age of patients presenting with intramuscular myxoma was 61 years (range, 15-85 years; median, 64 years). The mean lesion size was 6.9 cm (range, 3-17 cm; median, 6.3 cm). A peritumoral fat rind was present in 13 of the patients (65%) with myxoma, and an increased signal in the adjacent muscle on fluid-sensitive sequences was present in 11 patients (55%). Intramuscular myxomas were homogeneously low in signal intensity on T1-weighted MR sequences in 19 patients (95%), with all lesions showing a high signal intensity on T2-weighted or fluid-sensitive MR sequences. Twelve of the myxomas had well-defined borders, and eight had borders that were partially ill defined. Of the 11 lesions imaged after gadolinium administration, six (55%) showed intense heterogeneous enhancement. CONCLUSION: Findings of a mass that on MR images shows a perilesional fat rind, the signal intensity of fluid, and an increased signal in the adjacent muscle on T2-weighted or fluid-sensitive MR sequences are strongly suggestive of intramuscular myxoma. The degree of lesion enhancement varies but is most frequently intense and heterogeneous. Although the recognition of these features likely will not obviate biopsy of any individual lesion, it will allow more accurate prebiopsy diagnosis and preoperative planning.

Adolescent↗

PubMedDate not supplied

Overuse injuries of the upper extremity in the competitive athlete: magnetic resonance imaging findings associated with repetitive trauma.

Overuse injuries are a very common cause of pain in athletes, accounting for a significant loss of training time and missed competitions. Magnetic resonance imaging (MRI) is playing an increasing role in facilitating the expeditious and safe return of these individuals to their preinjury level of physical performance by allowing accurate diagnosis. Sports physicians are increasingly relying on the exquisite anatomic detail afforded by this technique to formulate diagnoses that assist with the optimal management of these athletic injuries. Some upper extremity overuse entities are well recognized; two examples are medial epicondylitis, classically appearing in baseball pitchers, and lateral epicondylitis, in tennis players. Other less well-known injuries of the upper extremity, such as intersection syndrome in rowers and distal clavicular stress fractures in weightlifters, are frequent occurrences in certain circles of athletes. The following article is a pictorial review of the MRI findings of upper extremity overuse injuries encountered in the competitive athlete, with an emphasis on the sports scenarios in which they occur. We will depict mechanisms of injury and applicable anatomy and show characteristic imaging findings. A wide range of entities are addressed, including but not limited to overuse injuries occurring in baseball, swimming, gymnastics, weightlifting, bowling, and cycling.

Athletic Injuries↗

PubMedDate not supplied

Evaluation of collateral ligament injuries of the metacarpophalangeal joints with magnetic resonance imaging and magnetic resonance arthrography.

Injuries of the collateral ligaments of the metacarpophalangeal (MCP) joints of the hand require accurate diagnosis and prompt treatment to prevent loss of function. The most common and well-known collateral ligament injury is injury to the ulnar collateral ligament of the first MCP joint of the hand, often referred to as a gamekeeper injury. Although less common, injuries involving the collateral ligaments of the second through fifth digits and the radial collateral ligament of the first digit also occur. The diagnosis of collateral ligament injury is often made clinically, however, magnetic resonance imaging and magnetic resonance arthrography of the MCP joints can be very useful in the evaluation of severity of the injury. This provides important information for the hand surgeon and aids in treatment planning. Imaging of the collateral ligaments requires small fields of view and several technical considerations can provide improved image quality. These factors will be discussed and illustrated in this article.

Arthrography↗

PubMedDate not supplied

Imaging characteristics of bone graft materials.

Bone graft materials are widely used in reconstructive orthopedic procedures to promote new bone formation and bone healing, provide a substrate and scaffolding for development of bone structure, and function as a means for direct antibiotic delivery. Bone graft materials include autografts, allografts, and synthetic substitutes. An autograft (from the patient's own bone) supplies both bone volume and osteogenic cells capable of new bone formation. The imaging appearance of an autograft depends on its type, composition, and age. Autografts often appear as osseous fragments at radiography. At computed tomography (CT), autografts appear similar to the adjacent cortical bone. At magnetic resonance (MR) imaging, however, autografts have a variable appearance as a consequence of the viable marrow inside them, a feature not present in other graft materials. An allograft (from cadaveric bone) has an appearance similar to that of cortical bone on radiographs and CT images. An allograft in the form of bone chips or morsels does not show those features on radiographs and CT images, but instead appears as a conglomerate with medium to high opacity and attenuation within the bone defect. In the immediate postoperative period, allografts appear hypointense on both T1- and T2-weighted MR images. Hematopoietic tissue replaces the normal fatty marrow in the later phases of graft incorporation. Synthetic bone substitutes are much more variable in imaging appearance. As the use of bone allografts and synthetic substitutes increases, familiarity with postoperative imaging features is essential for differentiation between grafts and residual or recurrent disease.

Bone Substitutes↗