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69


Radiology quiz case 2 [Case Report]

Jiang, Nancy; Pramanik, Bidyut; Darvishian, Farbod; Jethanamest, Daniel; Myssiorek, David
PMID: 20083788
ISSN: 1538-361x
CID: 106283

A new software tool to optimize frequency table selection for cochlear implants

Jethanamest, Daniel; Tan, Chin-Tuan; Fitzgerald, Matthew B; Svirsky, Mario A
HYPOTHESIS: When cochlear implant (CI) users are allowed to self-select the 'most intelligible' frequency-to-electrode table, some of them choose one that differs from the default frequency table that is normally used in clinical practice. BACKGROUND: CIs reproduce the tonotopicity of normal cochleas using frequency-to-electrode tables that assign stimulation of more basal electrodes to higher frequencies and more apical electrodes to lower frequency sounds. Current audiologic practice uses a default frequency-to-electrode table for most patients. However, individual differences in cochlear size, neural survival, and electrode positioning may result in different tables sounding most intelligible to different patients. No clinical tools currently exist to facilitate this fitting. METHODS: A software tool was designed that enables CI users to self-select a most intelligible frequency table. Users explore a 2-dimensional space that represents a range of different frequency tables. Unlike existing tools, this software enables users to interactively audition speech processed by different frequency tables and quickly identify a preferred one. Pilot testing was performed in 11 long-term, postlingually deaf CI users. RESULTS: The software tool was designed, developed, tested, and debugged. Patients successfully used the tool to sample frequency tables and to self-select tables deemed most intelligible, which for approximately half of the users differed from the clinical default. CONCLUSION: A software tool allowing CI users to self-select frequency-to-electrode tables may help in fitting postlingually deaf users. This novel approach may transform current methods of CI fitting
PMCID:2962926
PMID: 20729774
ISSN: 1537-4505
CID: 113658

Speech perception in congenitally deaf children receiving cochlear implants in the first year of life

Tajudeen, Bobby A; Waltzman, Susan B; Jethanamest, Daniel; Svirsky, Mario A
OBJECTIVE: To investigate whether children implanted in the first year of life show higher levels of speech perception than later-implanted children, when compared at the same ages and to investigate the time course of sensitive periods for developing speech perception skills. More specifically, to determine whether faster gains in speech perception are made by children implanted before 1 year old relative to those implanted at 2 or 3 years. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary academic referral center. PATIENTS: 117 children with congenital profound bilateral sensorineural hearing loss, with no additional identified disabilities. INTERVENTION: Cochlear implantation in the first, second, or third year of life. MAIN OUTCOME MEASURE: Development curves showing Lexical Neighborhood Test (LNT) word identification scores as a function of age. RESULTS: Children implanted within the first year of life have a mean advantage of 8.2% LNT-easy word scores over those implanted in the second year (p < 0.001) and a 16.8% advantage in LNT-easy word scores over those implanted in the third year of life (p < 0.001). These advantages remained statistically significant after accounting for sex, residual hearing, and bilateral cochlear implant use. When speech perception scores were expressed as a function of 'hearing age' rather than chronological age, however, there were no significant differences among the 3 groups. CONCLUSION: There is a clear speech perception advantage for earlier-implanted children over later-implanted children when compared at the same age but not when compared at the same time after implantation. Thus, the sensitive period for developing word identification seems to extend at least until age 3 years
PMCID:2962931
PMID: 20814343
ISSN: 1537-4505
CID: 113659

Conditional survival in head and neck melanoma [Meeting Abstract]

Jethanamest D.; Morris L.G.T.; Delacure M.D.
Objectives: To report changes in survival probabilities as patients survive one or more years with head and neck melanoma, and to characterize prognostic factors for this conditional survival statistic. Study Design: Retrospective population-based cohort study. Methods: All subjects from the Surveillance, Epidemiology and End Results (SEER 17) database of the National Cancer Institute with head and neck cutaneous melanoma were analyzed. Using the life table actuarial method, conditional 5 year disease specific survival (DSS) and relative survival were determined for patients surviving one to ten years after diagnosis. Grouped comparisons were performed for anatomic subsites within the head and neck and the rest of the body. Probabilities were also stratified by histologic subtype, thickness of invasion and lymph node status. Results: Five year DSS for scalp and neck melanomas increases from 83.1% to 93.9% for patients surviving five years, compared to an increase from 89.2% to 96.2% for other anatomic sites. Nodular melanoma displayed the worst initial survival among histologic subtypes (73.4%) but improves to 91% at five years. Conditional DSS for node positive patients improves from 47.9% to 83.1%. Survival at diagnosis is stratified by tumor thickness from 96.7% (T1) to 62.3% (T4), but tends to converge between five to ten years of survivorship. Conclusions: For patients with head and neck melanoma who have survived several years, conditional survival provides accurate and useful prognostic information. In general, expected survival increases with time survived since diagnosis, and for low and high T-stage patients, conditional survival statistics converge over time
EMBASE:2011036436
ISSN: 0023-852x
CID: 122700

Potential hazards of the harmonic scalpel [Letter]

Mallur, Pavan S; Jethanamest, Daniel; Shemen, Larry J
PMID: 19643277
ISSN: 0194-5998
CID: 101323

Evaluation of the short hybrid electrode in human temporal bones

Roland, J Thomas Jr; Zeitler, Daniel M; Jethanamest, Daniel; Huang, Tina C
HYPOTHESIS: The current hybrid electrode can be inserted without trauma to the temporal bone and, after insertion, assumes a position within the scala tympani near the outer cochlear wall just beneath the basilar membrane. BACKGROUND: Conservation of residual hearing after cochlear implant electrode insertion requires a special insertion technique and an atraumatic short electrode. This allows electroacoustic stimulation in ears with significant residual hearing. METHODS: Human cadaveric temporal bones were implanted with soft surgical technique under fluoroscopic observation. Dehydrated and resin-impregnated bones are dissected. Real-time electrode insertion behavior and electrode position were evaluated. The bones are examined for evidence of insertion-related trauma. RESULTS: No gross trauma was observed in the implanted bones, and the electrode dynamics evaluation revealed smooth scala tympani insertions. CONCLUSION: Atraumatic insertion of the 10-mm hybrid electrode can be accomplished using an appropriate cochleostomy and insertion technique
PMID: 18317395
ISSN: 1531-7129
CID: 80286

The effect of perimodiolar placement on speech perception and frequency discrimination by cochlear implant users

Fitzgerald, Matthew B; Shapiro, William H; McDonald, Paulette D; Neuburger, Heidi S; Ashburn-Reed, Sara; Immerman, Sara; Jethanamest, Daniel; Roland, J Thomas; Svirsky, Mario A
CONCLUSION: Neither speech understanding nor frequency discrimination ability was better in Nucleus Contour users than in Nucleus 24 straight electrode users. Furthermore, perimodiolar electrode placement does not result in better frequency discrimination. OBJECTIVES: We addressed three questions related to perimodiolar electrode placement. First, do patients implanted with the Contour electrode understand speech better than with an otherwise identical device that has a straight electrode? Second, do these groups have different frequency discrimination abilities? Third, is the distance of the electrode from the modiolus related to frequency discrimination ability? SUBJECTS AND METHODS: Contour and straight electrode users were matched on four important variables. We then tested these listeners on CNC word and HINT sentence identification tasks, and on a formant frequency discrimination task. We also examined X-rays and measured the distance of the electrodes from the modiolus to determine whether there is a relationship between this factor and frequency discrimination ability. RESULTS: Both speech understanding and frequency discrimination abilities were similar for listeners implanted with the Contour vs a straight electrode. Furthermore, there was no linear relationship between electrode-modiolus distance and frequency discrimination ability. However, we did note a second-order relationship between these variables, suggesting that frequency discrimination is worse when the electrodes are either too close or too far away from the modiolus
PMID: 17453457
ISSN: 0001-6489
CID: 73408

Esthesioneuroblastoma: a population-based analysis of survival and prognostic factors

Jethanamest, Daniel; Morris, Luc G; Sikora, Andrew G; Kutler, David I
OBJECTIVES: To investigate the characteristics associated with survival in esthesioneuroblastoma and to determine whether the modified Kadish staging system can predict outcome. DESIGN: Retrospective population-based cohort study. SUBJECTS: All patients in the Surveillance, Epidemiology, and End Results tumor registry diagnosed as having esthesioneuroblastoma (1973-2002). MAIN OUTCOME MEASURES: The modified Kadish stage and the overall and disease-specific survival rates were determined. RESULTS: The cohort included 311 patients with a mean age of 53 years and a unimodal age distribution. The overall 5- and 10-year survival rates were 62.1% and 45.6%, respectively. The modified Kadish staging system was applied to 261 patients. Kaplan-Meier analysis showed the overall and disease-specific survival rates at 10 years to be 83.4% and 90%, respectively, for patients with stage A disease; 49% and 68.3% for patients with stage B disease; 38.6% and 66.7% for patients with stage C disease; and 13.3% and 35.6% for patients with stage D disease. Log-rank test comparisons found Kadish stage (P<.01), treatment modality (P<.002), lymph node status (P<.01), and age at diagnosis (P<.001) to be significant predictors of survival. Cox regression analysis confirmed that Kadish stage remained a significant predictor of disease-specific survival. CONCLUSION: The modified Kadish staging system, lymph node status, treatment modality, and age are useful predictors of survival in patients who present with esthesioneuroblastoma
PMID: 17372086
ISSN: 0886-4470
CID: 71423

Radiology quiz case 1. Schwannoma of the tongue [Case Report]

Jethanamest, Daniel; Kanowitz, Seth J; Tran, Theresa N
PMID: 17178953
ISSN: 0886-4470
CID: 70095