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J P LiPuma

Publications and source records attributed to J P LiPuma.

At least 19 recordsLinked to original sources
PubMed1986

Magnetic resonance imaging of the prostate.

The prostate was examined by magnetic resonance imaging (MRI) in 33 subjects, including five normal volunteers, 18 with prostatic carcinomas, seven with benign nodular hyperplasias, two cases of acute prostatitis, and one case of chronic prostatitis. Of 18 prostatic carcinomas, 16 produced an inhomogeneous signal intensity, with areas of diminished signal on T1-weighted scans and usually increased signal on T2-weighted images relative to the rest of the prostate. However, a similar appearance was also seen in five cases of benign nodular hyperplasia. It is doubtful at present whether MRI is able to reliably differentiate benign from malignant prostatic disease. Extraprostatic tumor extension and pelvic adenopathy was well shown, and MRI is very promising as a method for the preoperative staging of known prostatic carcinomas.

Carcinoma↗
PubMed1986

Magnetic resonance imaging of the genitourinary tract.

MRI is in its infancy as a clinical imaging tool. It is undergoing intensive investigation in various areas of the body. Evaluation of the brain and spine is superb, and in some areas of the brain, like the posterior fossa, it is thought to be superior to CT. Evolving indications for body scanning include staging of pelvic malignancies, evaluation of liver malignancy, evaluation and staging of musculoskeletal problems, and, to a lesser degree, staging of renal malignancies and evaluation of vascular disease. The main problem in body imaging stems from image degradation because of respiratory motion that is transmitted to upper abdominal organs. Respiratory gating of image acquisition or utilization of short heavily T1-weighted pulse sequences will likely overcome this problem in due time. Minimizing motion artifact will make MR images comparable to, if not better than, CT images with regard to transverse anatomic display, and MR images have the added advantage of multiplanar scanning, which can be done directly, without need of additional computer reconstruction time and without having to move the patient. The second major problem in MRI is the lack of understanding of equipment potential. Unlike conventional radiography and CT, in which the behavior of the X-ray beam is understood with regard to image formation, in MRI new parameters are used to generate images. As stated earlier, MR signal intensity is due to hydrogen concentration, T1 and T2 relaxation times of the tissue, and flow of protons through the imaged volume. How these factors are weighted depends on pulse sequence selection, and thus image contrast and information content of the scans change. On the surface, these images display anatomic information as do other imaging modalities, but manipulation of pulse sequences may ultimately lead to the ability to demonstrate physiologic and chemical parameters previously unavailable in imaging. Current research is geared to help extract this data by testing new pulse sequences, using different types of receiver RF coils, and using MR-specific contrast materials. Minor MRI problems such as long scan times are being dealt with to decrease time to an acceptable length. The nonvisualization of soft tissue calcifications will probably remain a problem that may have to be weighed against other known advantages. At this time further research and clinical experience are the key to what is needed in MRI, to gain further knowledge with regard to imaging physiologic phenomena, such as flow and spectroscopy, and possibly to monitor the chemical basis of disease.(ABSTRACT TRUNCATED AT 400 WORDS)

Calcinosis↗
PubMed1984

Magnetic resonance imaging of the breast. Work in progress.

Ten normal volunteers and 45 patients with breast abnormalities were examined with magnetic resonance (MR), utilizing a 0.3-tesla superconducting magnet. In all patients, MR detected an abnormality that corresponded to the area of pathology seen on either a mammogram or computed tomographic (CT) scan. An appreciable advantage of MR over mammography was observed in patients with cysts and in those with areas of asymmetric dysplastic breast tissue. Abnormalities on MR images appeared as areas of low signal intensity relative to adjacent normal ductal and fatty tissue. The configuration of a lesion on MR permitted distinction between a benign and a malignant process.

Adolescent↗
PubMed1984

CT-guided liver biopsies: eight years' experience. Work in progress.

In the past eight years 180 patients with liver abnormalities demonstrated on computed tomography (CT) underwent CT-guided biopsies with 22-guage Madayag, 14-gauge Travenol, or 18-gauge Menghini needles used singly or in combination. Cytologic and pathologic results were tabulated and correlated with the subsequent surgical or autopsy findings and with clinical follow-up ranging from three months to three years. Complications of the procedures were also recorded. It is concluded that cutting needle biopsies provide a higher yield of diagnostic tissue compared with aspiration biopsies (89.9% versus 65%) without a significant increase in complications (1.44% versus 0.83%). The techniques utilized, risk of complications, and the indications for biopsy are discussed.

Biopsy↗
PubMed1984

Magnetic resonance imaging of the abnormal female pelvis.

Twenty-three women with 27 instances of pelvic pathology were evaluated by magnetic resonance imaging (MRI). Different pulse sequences were used, which varied the dependence of the images on T1 and T2. Sonography was performed on 22 of the 23 patients. Five patients had CT examinations, including the patient who did not have sonography. MRI was also done in four normal volunteers. The spatial resolution of the MRI scans with short TR and TE intervals approached that of CT. There was overlap of MRI signal characteristics between various pathologic entities and also within the same entity (e.g., cystadenomas and endometriomas).

Appendicitis↗
PubMed1984

Magnetic resonance imaging of the pelvis.

Magnetic resonance imaging (MRI) is a very promising modality for evaluation of the pelvis. Its major role appears likely to be the staging of known malignancies. In this article, the appearance of normal pelvic anatomy on MR scans is presented, as well as a discussion of the use of MRI in the detection and evaluation of pathologic conditions and a comparison of MRI with CT.

Abscess↗
PubMed1984

Magnetic resonance imaging of the kidney.

In this article, the principles of MR renal evaluation are reviewed. Techniques and pulse sequences used for evaluation are described. The author presents his experience with MRI in the evaluation of normal anatomy of the kidney, renal masses (cystic and solid), renal medical diseases, and renal transplants and compares this technique with conventional imaging modalities.

Abscess↗
PubMed1983

Initial experience with nuclear magnetic resonance (NMR) imaging of the human breast.

Two patients with breast abnormalities, one malignant and one benign, were studied with nuclear magnetic resonance (NMR) imaging utilizing a cryogenic superconducting magnet. Three-dimensional NMR images were obtained in one case and single slice planar images were obtained in the other. The NMR images correlated well with the corresponding mammograms. Although both conditions exhibited a different signal intensity for the area of abnormality compared to adjacent ductal and fatty tissue, the configuration of the abnormal areas allowed distinction between benign and malignant process.

Breast Diseases↗
PubMed1983

Clinical comparison of small-and large-caliber cutting needles for biopsy.

A 22 gauge "skinny core" (Madayag) biopsy needle, an 18 gauge Menghini needle, and a 14 gauge Tru-cut needle were compared in 51 patients. The Madayag needle was found to have a high recovery rate and provided adequate histological information in a large percentage of cases. However, the larger needles more consistently demonstrated a higher recovery rate and diagnostic specimen than the Madayag needle. The authors recommend that the radiologist become familiar with all three types of needles to facilitate selection of the proper instrument in each case.

Biopsy, Needle↗