Investigative radiology
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Investigative radiology · Jun 1992
Normal renal blood flow measurement using phase-contrast cine magnetic resonance imaging.
This study assesses the ability of a cardiac-gated phase-contrast magnetic resonance imaging (MRI) technique to measure renal blood flow (RBF) noninvasively in humans. ⋯ Reproducible noninvasive measurement of normal RBF is possible with the phase-contrast MRI technique used to measure renal venous blood flow.
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Investigative radiology · Dec 1991
Fatty liver. Chemical shift phase-difference and suppression magnetic resonance imaging techniques in animals, phantoms, and humans.
In vitro animal and human models were used to evaluate the potential of chemical shift magnetic resonance imaging (MRI) for assessing fatty liver. Phantoms of varying fat content were created from mayonnaise-agar preparations. Fatty liver was induced in eight rats by feeding them ethanol for three to six weeks (36% of total calories), whereas eight control rats were fed a normal diet. ⋯ There was no overlap between MR-derived fat fractions for control (2.6%-5.7%) versus ethanol-fed rats (7.7%-17.9%, P = .0002). Human liver considered to be fatty by visual inspection (n = 8) had higher relative signal decrease than nonfatty liver (n = 22) (P less than .001). Phantom, animal, and human data demonstrate that comparison of T1-weighted in-phase and opposed-phase images is both practical and sensitive in the detection and grading of fatty liver.
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Investigative radiology · Oct 1991
Effectiveness of transcutaneous electrical nerve stimulation (TENS) for analgesia during biliary lithotripsy.
The effectiveness of transcutaneous electrical nerve stimulation (TENS) in controlling pain during biliary extracorporeal shockwave lithotripsy (BESWL) was assessed in 100 patients with symptomatic gallbladder calculi. Patients were divided into four groups: TENS electrodes were placed on the back at cutaneous anesthesia sites and on the right leg and the gallbladder acupuncture site in groups A and B. Electrodes were "turned on" only in group A. ⋯ The differences in the amount of analgesic used and the pain experiences by the patients in all groups were not statistically significant. The proportion of patients requiring intravenous analgesia in each group was also not significantly different (72%, 80%, 68%, 76% in groups A to D, respectively). Thus, TENS did not help in reducing the amount of intravenous analgesia required or the average pain perceived by the patient during lithotripsy treatment.
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Investigative radiology · Sep 1991
In-house testing in emergency radiology. A method for teaching and credentialling radiology residents.
Residents frequently learn emergency radiology simply by on-the-job experience. As an educational tool and as a credentialling vehicle, the authors developed an examination consisting of imaging unknowns as well as written questions. ⋯ They now regard the follow-up conferences as the best-organized instruction in emergency radiology in the training program. The authors' experiences suggest that in-house examinations can serve as an important means for teaching and credentialling in emergency radiology.