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L H Wetzel

Publications and source records attributed to L H Wetzel.

30 records · Page 2Linked to original sources
PubMed1990

Soft-tissue tumors of the foot: value of MR imaging for specific diagnosis.

We reviewed MR imaging findings in 14 patients with primary soft-tissue tumors of the foot and compared them with surgical and pathologic findings to determine the value of MR imaging in anatomic localization, delineation, and characterization of such lesions. Nine tumors (64%) were benign, and five (36%) were malignant. The anatomic location (compartment, space, relation to specific tendon) and extent of all tumors were accurately shown by MR imaging. Twelve tumors (86%) were correctly characterized as benign or malignant. Eight (89%) of nine benign lesions showed distinctive MR imaging features that correctly suggested a specific diagnosis. These included hemangioma (high T2-weighted intensity and internal septa), ganglion cyst (homogeneous, high T2-weighted weighted intensity and peritendinous location), plantar fibromatosis (nodularity of plantar aponeurosis with low intensity on all sequences), and pigmented villonodular synovitis (low T2-weighted intensity and lower intensity rim). Aggressive fibromatosis (one case) could not be characterized. Four (80%) of five malignant neoplasms had MR imaging findings suggesting soft-tissue sarcoma. Two synovial sarcomas were inhomogeneous and showed extensive peritendinous growth. Two clear cell sarcomas arose at the origin of the plantar aponeurosis and infiltrated adjacent muscle. A small clear cell sarcoma could not be characterized as benign or malignant. MR imaging of the foot is accurate in showing the extent of soft-tissue tumors, which is helpful for surgical planning. Determination of their specific anatomic location may help characterize some tumors. Although our series is small, it appears that MR imaging often suggests a specific diagnosis in certain benign soft-tissue tumors of the foot and may often correctly distinguish benign from malignant tumors.

Adolescent↗
PubMed1989

Small renal neoplasms: clinical, pathologic, and imaging features.

Small renal neoplasms are being found more often because of the widespread use of abdominal CT and sonography. Little is known about their natural history. We therefore retrospectively reviewed clinical, pathologic, and imaging findings in 22 patients with surgically confirmed solitary renal neoplasms that were 3 cm or less in diameter. Eighteen lesions were first found by CT, three by sonography, and one by IV urography. Three lesions were discovered because the patients had hematuria. Nineteen were incidental radiologic diagnoses in patients without renal symptoms. Of 22 neoplasms, 15 (68%) were renal cell carcinomas, six (27%) were oncocytomas, and one (5%) was a lymphoma. Fourteen (93%) of the 15 carcinomas were confined to the kidney, and one showed microscopic capsular invasion. Metastases did not develop in any patient with carcinoma, indicating that small carcinomas usually have good prognoses. Patients with carcinomas had a mean follow-up of 42 months. All neoplasms were visible on CT. However, characterization of these lesions sometimes required a combination of CT and sonography and occasionally angiography. The carcinomas, oncocytomas, and solitary renal lymphoma could not be distinguished radiologically. Small renal neoplasms are most often found incidentally by CT performed in patients without renal complaints. Most are low-stage carcinomas, and some are oncocytomas.

Adenoma↗
PubMed1988

Hardcopy recordings of analog and digital images.

The increase in the use of various imaging modalities demands higher quality and more efficacious analog image recordings. Laser electronic recordings with digital array prints of 4K X 5K X 12 bits using laser-sensitive film or paper are being evaluated. Dry silver paper recordings are being improved and evaluated. High resolution paper dot printers are being studied to determine their gray scale capabilities. The authors have conducted a study to evaluate the image quality, costs, clinical use, and acceptability of CT, MRI, DSA, digital radiography, and radionuclide images recorded by the seven different printers (three laser, three silver paper, and one dot) in comparison with conventional film recording. This paper describes the technical developments and instrumentation of digital laser film and analog paper recorders and presents the results of our study.

Copying Processes↗
PubMed1988

Normal penile anatomy and abnormal penile conditions: evaluation with MR imaging.

The appearance of the normal penis and of a variety of penile abnormalities on magnetic resonance (MR) images was studied in 55 patients with either medium (0.35 T) or high (1.5 T) magnetic field strengths. Penile morphologic characteristics with anatomic detail of the corpora cavernosa and corpus spongiosum were demonstrated in each patient. MR images clearly displayed congenital anomalies (n = 6), penile prostheses (n = 7), fibrous tissue or hematoma due to trauma (n = 8), and fibrous plaque in Peyronie disease (n = 3). MR imaging also demonstrated urethral (n = 6) and penile (n = 5) neoplasms and allowed tumor staging, thus facilitating the surgical approach.

Adolescent↗
PubMed1987

Malignant nerve-sheath neoplasms in neurofibromatosis: distinction from benign tumors by using imaging techniques.

Malignant peripheral nerve-sheath neoplasms frequently complicate neurofibromatosis causing pain, enlarging masses, or neurologic deficits. However, similar findings sometimes also occur with benign nerve neoplasms. Our study was done retrospectively to determine if imaging techniques can differentiate malignant from benign nerve tumors in neurofibromatosis. Eight patients with symptomatic neoplasms (three benign, five malignant) were studied by CT in eight, MR in six, and 67Ga-citrate scintigraphy in seven. Uptake of 67Ga occurred in all five malignant lesions but not in two benign neoplasms studied. On CT or MR, all eight lesions, including three benign neoplasms, showed inhomogeneities. Of five lesions with irregular, infiltrative margins on CT or MR, four were malignant and one was benign. Of three lesions with smooth margins, one was malignant and two were benign. One malignant neoplasm caused irregular bone destruction. Accordingly, CT and MR could not generally distinguish malignant from benign lesions with certainty. However, both CT and MR provided structural delineation to help surgical planning for both types of lesion. 67Ga scintigraphy appears promising as a screening technique to identify lesions with malignant degeneration in patients with neurofibromatosis. Any area of abnormal radiogallium uptake suggests malignancy warranting further evaluation by CT or MR. Biopsy of any questionable lesion is essential.

Adolescent↗
PubMed1986

MR imaging and CT of extrahepatic cavernous hemangiomas.

Ten extrahepatic cavernous hemangiomas in seven patients were evaluated by MR and CT. MR was done with a 1.0-T superconducting magnet and spin-echo imaging. The lesions occurred in the musculoskeletal system, parotid gland, and spleen. MR and CT features of hemangiomas were compared, and MR findings in hemangiomas were also compared with those in eight musculoskeletal tumors of nonvascular origin. MR detected 10 hemangiomas, while nine were shown by CT. Also, MR was more accurate than CT in three patients in determining the true extent of hemangiomas. At a pulse-repetition interval of 2000 msec and an echo delay time of 90 msec, all hemangiomas were markedly hyperintense compared with skeletal muscle. Quantitatively, at this pulse sequence, intensity ratios of hemangiomas to skeletal muscle were all seven or greater (mean = 9.89), while the ratios for other tumors were usually less than seven (mean = 5.14). These means differed significantly (p less than .001). Small cavernous hemangiomas were homogeneous, well-defined round or oval lesions, while large hemangiomas consisted of dilated, tortuous vascular channels. Other tumors, however, were usually heterogeneous owing to hemorrhage and necrosis and had irregular margins. MR may, therefore, be useful for distinguishing cavernous hemangiomas from other soft-tissue tumors, particularly sarcomas.

Adolescent↗
PubMed1986

Imaging studies in neonatal herpes simplex encephalitis.

Herpes simplex encephalitis (HSE) is the most common form of sporadic encephalitis in man and usually results in death or permanent neurologic deficit. Neonatal HSE does not show the characteristic anatomic localization in the temporal lobe observed in adults and in older children which suggests that the disease process is different in this age group. The abnormalities observed with radionuclide brain imaging and computed tomography (CT) are more diffuse and bilateral. The clinical outcome of the disease is highly dependent on early institution of therapy. Therefore, early diagnosis is critical. Knowledge of neonatal HSE imaging patterns may alert the clinician to the proper diagnosis.

Brain↗
PubMedDate not supplied

MR imaging of transarticular skip metastases from distal femoral osteosarcoma.

We describe a case in which magnetic resonance (MR) imaging of a distal femoral osteosarcoma showed transarticular skip metastases in the proximal tibia. These lesions were not found by conventional radiography, bone scintigraphy, or CT. Since detection of transarticular skip metastases has an important influence on surgical management, MR imaging of metaphyseal osteosarcomas should always include the bone on the opposite side of the joint.

Adult↗