Biomedical subjects

Jeremy Hornibrook

Publications and source records attributed to Jeremy Hornibrook.

3 recordsLinked to original sources

PubMed2006

Voice of postradiotherapy nasopharyngeal carcinoma patients: evidence of vocal tract effect.

This study was aimed at identifying acoustic and physiological measures useful for monitoring voice changes in postnasopharyngeal patients with nonlaryngeal malignancies, and providing evidences of vocal tract effect on voice through comparisons between individuals with and without intact vocal tract. Simultaneous acoustic-electroglottographic signals recorded during phonation of vowels /i/ and /a/ sustained at habitual, high, and low pitch levels were compared among 10 postradiotherapy patients with nasopharyngeal carcinoma (NPC), 10 voice patients (VPs) with intact vocal tract, and 10 healthy individuals with normal voice (NORM). Results from a series of discriminant analyses revealed that the NPC group generally exhibited lower signal-to-noise (SNR) and open quotient (OQ) and higher Formant 1 frequency (F(1)) and speed quotient (SQ) than the NORM group. Unlike both VP and NORM groups, the NPC group failed to show a pitch effect on all voice measures, including OQ, SQ, percent jitter, percent shimmer, and SNR, suggesting an effect of radiotherapy and/or vocal tract on laryngeal behaviors. For the vowel /i/, on the other hand, only the NPC and NORM groups showed a pattern of pitch-dependent F(1) raising, a reflection of increased pharyngeal narrowing. These findings suggested that the pitch effect on laryngeal behaviors differed not only between individuals with intact vocal tract and those without but also between those with structural and dynamic changes of vocal tract.

Adult↗

PubMed2005

A newly recognised cause of vertigo: horizontal canal variant of benign positional vertigo.

AIMS: To describe the presentation, causes, treatment, and outcomes of patients presenting with the newly recognised horizontal canal variant of benign positional vertigo (BPV); and to emphasise the importance of performing a positional test on all patients being assessed for vertigo. METHODS: The records on 400 patients presenting with BPV were analysed. Two detailed patient histories from 2004 are included. RESULTS: Forty-nine patients (12%) had horizontal canal BPV. The median presentation age was 59 years. In 17 patients, it presented de novo during repositioning treatment for 'classical' posterior canal BPV. Repositioning is in the horizontal plane, with the direction depending on whether the mechanism is canalithiasis or cupulolithiasis. CONCLUSIONS: Horizontal canal BPV explains nearly all variations on 'classical' (posterior canal) BPV. It accounts for at least 10% of BPV and has been frequently misdiagnosed. Repositioning is usually curative if the symptomatic ear is correctly identified.

Adult↗

PubMed2004

Horizontal canal benign positional vertigo.

The existence of horizontal canal benign positional vertigo (BPV) was predicted from temporal bone studies in 1973, but was not clinically confirmed until later. In this series of 300 patients with BPV, 35 (12%) were identified as having the horizontal canal variant. The essential features are the onset of vertigo when the patient assumes a supine position and bidirectional horizontal nystagmus as the head is turned from side to side. In one third it appeared as a canal "conversion" in patients undergoing repositioning treatment for posterior canal BPV. The mechanism can be canalithiasis or cupulolithiasis. Repositioning treatment is a 360 degrees horizontal head and body rotation that has a high success rate if the symptomatic ear is correctly identified.

Adult↗