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D C Fitzgerald

Publications and source records attributed to D C Fitzgerald.

4 recordsLinked to original sources
PubMed1992

Labyrinthine enhancement on gadolinium-enhanced magnetic resonance imaging in sudden deafness and vertigo: correlation with audiologic and electronystagmographic studies.

Sudden deafness with or without vertigo presents a difficult diagnostic problem. This article describes 12 patients with enhancement of the cochlea and/or vestibule on gadolinium-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (MRI), correlating the enhancement with the auditory and vestibular function. All patients were studied with T2-weighted axial images taken through the whole brain, enhanced 3-mm axial T1-weighted images taken through the temporal bone, and enhanced T1-weighted sagittal images taken through the whole brain. Cochlear enhancement on the side of hearing loss was found in all the patients. The vestibular enhancement correlated with both subjective vestibular symptoms and objective measures of vestibular function on electronystagmography. In 2 patients, the resolution of symptoms 4 to 6 months later correlated with resolution of the enhancement on MRI. No labyrinthine enhancement was seen in a series of 30 control patients studied with the same MRI protocol. Labyrinthine enhancement in patients with auditory and vestibular symptoms is a new finding and is indicative of labyrinthine disease. While abnormalities on electronystagmograms and audiograms are nonspecific and only indicate a sensorineural problem, enhanced MRI may separate patients with retrocochlear lesions, such as acoustic neuromas, from those in whom the abnormal process is in the labyrinth or the brain.

Adult↗
PubMed1991

Simultaneous intraoperative measurement of cardiac output by thermodilution and transtracheal Doppler.

Intraoperative measurement of cardiac output with transtracheal Doppler (DOP) was compared with that measured by thermodilution (TD). Cardiac output was measured simultaneously with both methods in 17 adult patients. For 86 pairs of measurements, the average difference between the two techniques was -0.21.min-1. This bias had a standard deviation of 1.71.min-1. The average of the absolute value of the difference between measurements made with the two techniques was 1.31.min-1, with a standard deviation of 1.11.min-1. The limits of agreement were -3.6 to 3.11.min-1. Linear regression yielded the following equation: DOP = 0.62 TD + 1.54 l.min-1 (r = 0.63). To evaluate the ability of transtracheal DOP to trend changes in cardiac output, the changes in cardiac output at sequential time points were compared for the two techniques. The average difference in the changes in cardiac output measured by the two techniques was 0.01.min-1. This bias had a standard deviation of 1.71.min-1. In conclusion, the transtracheal DOP technique did not reproduce the measurement of cardiac output by TD intraoperatively. Transtracheal DOP did not accurately trend changes in the TD measurement. These findings were obtained from patients with cardiovascular disease, and the conclusions may depend in part on the patient population and the investigators' experience with the transtracheal DOP technique.

Adult↗