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Hearing Disorders: HELP
Articles by Daniel D. E. Wong
Based on 4 articles published since 2010
(Why 4 articles?)
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Between 2010 and 2020, Daniel D. E. Wong wrote the following 4 articles about Hearing Disorders.
 
+ Citations + Abstracts
1 Article Characterization of retentive capacity of the subpericranial pocket in cochlear implants with and without a pedestal. 2016

Papsin, Blake C / Cushing, Sharon L / Hubbard, Bradley J / Wong, Daniel D E / Gordon, Karen A. ·Department of Otolaryngology-Head and Neck Surgery, University of Toronto. · Archie's Cochlear Implant Laboratory, Hospital for Sick Children, Toronto, Ontario, Canada. ·Laryngoscope · Pubmed #26228313.

ABSTRACT: OBJECTIVES/HYPOTHESIS: To quantify the retentive capacity (RC) of the subpericranial pocket (SpP) in children undergoing cochlear implantation (CI) and measure improvements in RC with the addition of a pedestal to the device base. Retention of a CI in an SpP relies on the integrity of surrounding tissues to determine device position and resist movement from external forces. We hypothesize that device position can be controlled and resistance to movement can be improved with placement of a small pedestal on the base of the CI receiver stimulator. STUDY DESIGN: Analysis of prospectively assembled data. METHODS: Ninety-seven patients (145 devices) underwent CI (48 bilateral, 49 unilateral). Intraoperatively, a force gauge measured the displacement force on a template Nucleus 5 (Cochlear Corporation, Sydney, Australia) implant placed in an SpP prior to routine suture fixation of a standard device. In 47 patients (64 devices), displacement forces were also measured for a custom template Nucleus 5 implant with pedestal. RESULTS: Average RC of the SpP for the standard device was 5.59 N ± 2.73 standard deviation (SD), which increased to 9.401 N ± 4.6267 SD with a pedestaled device. Resistance to displacement decreased significantly across trials in both groups (P <.0001). Retentive capacity of the SpP increased significantly with the addition of a pedestaled device (P < .0001). The interaction between device and trial was also found to be significant (P = .05). CONCLUSIONS: The RC of the SpP in children and the ability to resist device migration in the absence of fixation may improve with the addition of a pedestal attached to the device. LEVEL OF EVIDENCE: 2b. Laryngoscope, 126:1175-1179, 2016.

2 Article Bilateral input protects the cortex from unilaterally-driven reorganization in children who are deaf. 2013

Gordon, Karen A / Wong, Daniel D E / Papsin, Blake C. ·Archie's Cochlear Implant Laboratory The Hospital for Sick Children Room 6D08, 555 University Avenue, Toronto, Ontario, Canada. karen.gordon@utoronto.ca ·Brain · Pubmed #23576127.

ABSTRACT: Unilateral hearing in childhood restricts input along the bilateral auditory pathways, possibly causing permanent reorganization. In this study we asked: (i) do the auditory pathways develop abnormally in children who are bilaterally deaf and hear with a unilateral cochlear implant? and (ii) can such differences be reversed by restoring input to the deprived ear? We measured multichannel electroencephalography in 34 children using cochlear implants and seven normal hearing peers. Dipole moments of activity became abnormally high in the auditory cortex contralateral to the first implant as unilateral cochlear implant use exceeded 1.5 years. This resulted in increased lateralization of activity to the auditory cortex contralateral to the stimulated ear and a decline in normal contralateral activity in response to stimulation from the newly implanted ear, corresponding to poorer speech perception. These results reflect an abnormal strengthening of pathways from the stimulated ear in consequence to the loss of contralateral activity including inhibitory processes normally involved in bilateral hearing. Although this reorganization occurred within a fairly short period (∼1.5 years of unilateral hearing), it was not reversed by long-term (3-4 years) bilateral cochlear implant stimulation. In bilateral listeners, effects of side of stimulation were assessed; children with long periods of unilateral cochlear implant use prior to bilateral implantation showed a reduction in normal dominance of contralateral input in the auditory cortex ipsilateral to the stimulated ear, further confirming an abnormal strengthening of pathways from the stimulated ear. By contrast, cortical activity in children using bilateral cochlear implants after limited or no unilateral cochlear implant exposure normally lateralized to the hemisphere contralateral to side of stimulation and retained normal contralateral dominance of auditory input in both hemispheres. Results demonstrate that the immature human auditory cortex reorganizes, potentially permanently, with unilateral stimulation and that bilateral auditory input provided with limited delay can protect the brain from such changes. These results indicate for the first time that there is a sensitive period for bilateral auditory input in human development with implications for functional hearing.

3 Article Cortical function in children receiving bilateral cochlear implants simultaneously or after a period of interimplant delay. 2010

Gordon, Karen A / Wong, Daniel D E / Papsin, Blake C. ·Archie's Cochlear Implant Laboratory, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada. karen.gordon@utoronto.ca ·Otol Neurotol · Pubmed #20634775.

ABSTRACT: HYPOTHESIS: Children using bilateral cochlear implants (CIs) develop normal patterns of cortical activity when interimplant delays are minimized. BACKGROUND: It is not clear whether bilateral CIs can promote normally functioning bilateral auditory pathways in children. METHODS: Cortical responses were recorded from 64 cephalic sites in 2 normal hearing participants and 8 children with 3 to 4 years of bilateral CI experience (age at first CI, 0.9-4.1 yr; age at second CI, 1.1-9.7 yr; interimplant delay, 0-5.8 yr). RESULTS: Beamformer analyses on the dominant positive peak in CI users and P1 in normal hearers revealed that stimuli delivered from the left side evoked responses lateralized to right auditory cortex in the 2 participants with normal hearing and the 3 children receiving bilateral CIs with minimal interimplant delay at young ages. These 5 participants showed a shift in cortical lateralization away from the right cortical hemisphere when stimuli were moved to the right. In contrast, 4 of 5 children receiving bilateral CIs after longer delays and at older ages showed abnormal ipsilateral parietal activity in response to left stimuli and lateralization to the left cortical hemisphere in response to both right and left stimuli. The fifth child in this group showed abnormal lateralization to the ipsilateral cortex in response to both right and left stimuli. CONCLUSION: The data suggest that, after 3 to 4 years of bilateral CI use, normal-like patterns of bilateral cortical activity are promoted in children receiving bilateral CI with minimal interimplant delays and young ages but are not present in older children who had longer interimplant delays.

4 Article Lateralization of interimplant timing and level differences in children who use bilateral cochlear implants. 2010

Salloum, Claire A M / Valero, Jerome / Wong, Daniel D E / Papsin, Blake C / van Hoesel, Richard / Gordon, Karen A. ·Institute of Medical Science, University of Toronto, Canada. ·Ear Hear · Pubmed #20489647.

ABSTRACT: OBJECTIVES: Interaural level differences (ILD) and interaural timing differences (ITD) are important cues for locating sounds in space. Adult bilateral cochlear implant (CI) users use ILDs more effectively than ITDs. Few studies investigated the ability of children who use bilateral CIs to make use of these binaural cues. Our working hypothesis was that children using bilateral CIs are able to perceive changes in ITDs and ILDs similar to their normal-hearing (NH) peers. DESIGN: Participants were two groups of children; 19 bilateral implant users (CI) and nine NH children. The children in the CI group had received a second CI after 4.9 +/- 2.8 yrs of unilateral use. Children performed a four alternative forced-choice lateralization task in which they were asked to describe stimuli as coming from the left side, right side, middle of the head, or from both sides simultaneously. Stimuli were 500 msec trains of electrical pulses delivered to apical electrode no. 18 (CI group) or clicks (NH group) presented 11 times per second with either ITDs (0, 400, 1000, or 2000 microsec delay between sides) or level differences (0, 10, or 20 Current Units (CI group) or 0, 10, or 20 dB (NH group) difference between sides). ITDs were presented using current levels that were balanced using left and right electrically evoked brain stem responses. Stimulus levels evoking response amplitudes that were most similar were used. RESULTS: Responses from children in the CI group changed significantly with changes in ILD of bilateral stimuli, but not with changes in ITD. Responses from children in the CI group were significantly different from those in the NH group in three ways. Children in the CI group perceived bilaterally presented electrical pulses: (1) to come from the second implanted side more often than the first, (2) to rarely come from the middle, and (3) to come from both sides of the head simultaneously. Perceived changes in lateralization with ILD changes were correlated with differences in amplitudes of electrically evoked brain stem responses by the left versus right CI. CONCLUSIONS: The results of this study illustrate that children who use bilateral CIs can lateralize stimuli on the basis of level cues, but have difficulty interpreting interimplant timing differences. Perceived lateralization of bilaterally presented stimuli to the second implanted side in many of the stimulus conditions may relate to the use of different device generations between sides. Further differences from normal lateralization responses could be due to abnormal binaural processing, possibly resulting from a period of unilateral hearing before the provision of a second implant or due to insufficiently matched interimplant stimuli. It may be possible to use objective measures such as electrically evoked auditory brain stem responses wave eV amplitudes to provide balanced levels of bilateral stimulation in children who have had no binaural hearing experience.