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L Teresi

Publications and source records attributed to L Teresi.

13 recordsLinked to original sources
PubMed1996

A comparison of MRI and clinical examination of acute lateral ankle sprains.

Because of its excellent soft tissue contrast and ability to demonstrate soft tissue structures, magnetic resonance imaging is ideally suited to the evaluation of the soft tissues surrounding the ankle, including the lateral collateral ligaments. This study was undertaken to compare the clinical evaluation of 15 patients who suffered inversion injuries of the ankle with the results found on magnetic resonance imaging within 48 hours of the injury. Physical examination was found to be 100% accurate in the diagnosis of grade III ligament injuries but only 25% accurate in the diagnosis of grade II injuries. Clinicians most often underestimate the damage with a grade II ligament tear. Furthermore, other associated injuries, such as significant capsule ruptures and tendon damage, were often overlooked at physical examination.

Acute Disease↗
PubMed1994

Magnetic resonance angiography.

Magnetic resonance (MR) angiography is a broad and expanding field. The technology of MR angiograms is evolving to produce higher spatial resolution, faster acquisition times, and reduced artifact. Rather than a straight, linear evolution, this progress is going forward in a number of areas inherent to the MR imaging process. Considerable progress has been demonstrated in such diverse areas as flow-sensitized radiofrequency pulses, reduced background signal with off-resonance pulses, improved vessel depiction with reduced echo times via improved hardware and reconstruction techniques, and improved display with more powerful computer algorithms. This review is a brief survey and comparison of available techniques for the visualization of blood vessels within the human body.

Humans↗
PubMed1990

MR of the paranasal sinuses.

The purpose of this project was to examine the anatomy and pathology of the paranasal sinuses as seen by MR imaging. This was accomplished through correlations of MR images of normal volunteers with matched cadaver whole organ cryosections. The information obtained by MRI was compared to that of plain films and CT in the detection of a variety of conditions affecting the paranasal sinuses. The majority of the pathological processes could be quite adequately imaged by T1 weighted pulsing sequences. When more tissue specific information was required in some infiltrating malignant lesions, T2 weighting pulsing sequences are quite helpful for tumors that crossed the subarachnoid space into the central nervous system or in characterizing tissues in airless sinuses. Other than the single case of osteoid osteoma where X-ray studies were superior, magnetic resonance provided equal or superior information to the X-ray examinations.

Cadaver↗
PubMed1989

Head and neck lesions: MR-guided aspiration biopsy.

Aspiration biopsy guided with computed tomography (CT) has long been a valuable tool in the evaluation of head and neck disease. The ability to obtain diagnoses without the need for surgery has had a significant effect on patient treatment. Magnetic resonance (MR) imaging is now rapidly replacing CT as the primary imaging study for many head and neck diseases. The standard stainless steel needles used for CT-guided biopsy are unsuitable for MR-guided biopsy because significant ferromagnetic artifacts obscure the underlying anatomy. A new needle has recently been designed specifically for use with MR imaging. This needle has far less magnetic susceptibility and therefore does not cause significant image distortion. The authors describe the use of this needle in MR-guided aspiration biopsy of a variety of lesions in the head and neck.

Adult↗
PubMed1987

MR imaging of the intratemporal facial nerve by using surface coils.

MR images of the intratemporal portion of the facial nerve were obtained with surface coils using a 0.3-T permanent magnet whole-body imaging system. Various 2DFT spin-echo pulse sequences were used to produce 5-mm thick sections with 0.5-mm pixels on a 512 X 512 acquisition matrix. The MR images from normal volunteers were correlated with cryosection specimens of three fresh human cadavers. The seventh nerve was followed in the internal auditory and fallopian canal and through temporal bone to the stylomastoid foramen. The entire labyrinthine, tympanic, and mastoid portions, as well as the geniculate ganglion, could be shown with appropriate scan planes. MR produces excellent images of the facial nerve with high-contrast resolution. Unlike CT, no beam-hardening artifact from the temporal bone is apparent. MR should be a sensitive study for the evaluation of intratemporal facial nerve disease.

Facial Nerve↗
PubMed1986

Magnetic resonance imaging of the facial nerve. Normal anatomy and pathology.

Magnetic resonance imaging with surface coils permits visualization of the facial nerve from within the brainstem and continuing through a major portion of the parotid gland. Diagnostic capabilities have been expanded to include white matter disease that affects the tracts of the facial nerve within the brainstem and tumors of the parotid gland that involve the facial nerve trunks after the nerve exists from the stylomastoid foramen.

Facial Nerve↗
PubMedDate not supplied

Low cost MRI of the paranasal sinuses.

The use of automated tuning, automated MR protocol sequences, surface coils, and grouping of patients with similar examinations, patient throughput can be greatly accelerated for MRI scanning. These measures coupled with high volume scanning permit significant reductions in cost so that MRI can be performed at a price range equal to or less than plain films for some examinations. The ability of MRI to perform axial, sagittal and coronal scans with excellent tissue contrast raises the possibility of substituting MRI for sinus x-rays. Based on our preliminary experience we have the opinion that MR is equal to/or better than CT in this region. This preference is currently being investigated. Only the cost issue will be addressed in this report.

Costs and Cost Analysis↗
PubMedDate not supplied

MR imaging of acute subarachnoid hemorrhage.

The MR appearance of acute subarachnoid hemorrhage experimentally produced in Macaca monkeys and observed in patients with clinically documented acute subarachnoid hemorrhage is presented. Subarachnoid hemorrhages were produced in two Macaca Nemestrema monkeys using the technique of Frazee. CT and MR imaging were performed immediately after the procedure and at frequent intervals up to two week post hemorrhage. MR including T1 and T2 weighted multiplanar spin echo images were obtained. The imaging studies were compared with clinical evaluations and pathological specimens of all animals. Findings in the experimental animals are correlated with those observed in patients with clinically documented subarachnoid hemorrhage. The results show that acute subarachnoid hemorrhage (SAH) can be detected with MRI as isointense signal replacing normally black CSF spaces on T1 weighted images. Signal changes most likely relate to protein water binding associated with the clotting mechanism rather than oxidative denaturation of hemoglobin. Imaging performed experimentally and clinically beyond four days, however, showed a marked increase in signal intensity on T1 weighted images which probably does result from methemoglobin formation within the clot matrix. Although CT remains the gold standard in detecting acute SAH, MR does provide some sensitivity to its presence.

Acute Disease↗
PubMedDate not supplied

MR of hemorrhagic acoustic neuromas.

The magnetic resonance (MR) appearance of hemorrhagic acoustic neuromas has not previously been reported. Four patients with surgically proven acoustic neuromas containing spontaneous hemorrhage were preoperatively evaluated with MR imaging. All patients presented with new onset of symptoms and three had subarachnoid hemorrhage. Signal changes on T1- and T2-weighted spin echo sequences were characteristic for acute, subacute and chronic intraparenchymal hemorrhage. Recognition of hemorrhagic changes on MR is important since more rapid surgical intervention is required in this patient subgroup.

Adult↗
PubMedDate not supplied

MR body stereotaxis: an aid for MR-guided biopsies.

The use of a new body stereotactic system to facilitate magnetic resonance (MR) guided biopsies is described. A skin entry point is first found using a localizer MR scan. The articulating arm of the stereotactic unit is then used to aim the MR needle at the entry point and accurately maintain the needle at the correct angle to intersect the target area. Complex angles may be used to allow needle passes outside the scan plane. This is accomplished by angling the arm out of the plane of the section.

Biopsy↗