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Objectives: To examine the hypothesis that infants receiving a degraded auditory signal have more difficulty segmenting words from fluent speech if familiarized with the words presented in both speech and sign compared to familiarization with the words presented in speech only. Study Design: Experiment utilizing an infant-controlled visual preference procedure. Methods: Twenty 8.5-month-old normal-hearing infants completed testing. Infants were familiarized with repetitions of words in either the speech + sign (n = 10) or the speech only (n = 10) condition. Infants were then presented with four six-sentence passages using an infant-controlled visual preference procedure. Every sentence in two of the passages contained the words presented in the familiarization phase, whereas none of the sentences in the other two passages contained familiar words. Results: Infants exposed to the speech + sign condition looked at familiar word passages for 15.3 seconds and at nonfamiliar word passages for 15.6 seconds, t (9) = −0.130, p = .45. Infants exposed to the speech only condition looked at familiar word passages for 20.9 seconds and to nonfamiliar word passages for 15.9 seconds. This difference was statistically significant, t (9) = 2.076, p = .03. Conclusions: Infants' ability to segment words from degraded speech is negatively affected when these words are initially presented in simultaneous speech and sign. The current study suggests that a decreased ability to segment words from fluent speech may contribute towards the poorer performance of pediatric cochlear implant recipients in total communication settings on a wide range of spoken language outcome measures.

To investigate visual-motor integration (VI) skills of prelingually deaf (PLD) children before and after cochlear implantation (CI) and investigate correlations with spoken-language and related processing measures.Study 1 was a longitudinal study in which VI was tested preimplant. Study 2 was a cross sectional study of school-age children who used a CI for2 years.In study 1, a standardized design-copying task was administered preimplant, and spoken-language data were obtained at intervals up to 4 years postimplantation. Analyses were conducted to determine if preimplant VI scores were predictive of various spoken-language measures. In study 2, standardized design copying and speeded maze tracing tasks were administered along with speech perception, vocabulary, and related processing measures.Whereas preimplant VI scores for children in study 1 fell within the typical range based on age-equivalent norms, postimplant VI standard scores in study 2 were low compared to the normative sample. Postimplant VI scores were inversely related to age at implantation. Preimplant VI scores were robustly predictive of most, but not all, spoken-language outcome scores. Postimplant design copying scores were also correlated with spoken-language and related processing measures whereas maze-tracing scores were less robustly related to these measures.Early auditory and linguistic experience may impact the development of VI skills. VI is a preimplant predictor of later spoken language outcomes. Design copying and speeded maze tracing tasks appear to tap different sets of cognitive resources in PLD children with CIs.

Objectives/Hypothesis: Stem cell replacement therapy has the potential to treat or cure an array of degenerative neurologic disorders, including sensorineural deafness. However, little is known about the potential for marrow-derived stem cells (MSCs) to take on properties of spiral ganglion neurons. The main purpose of this prospective animal study was to evaluate the survival of MSCs transplanted into the gerbil cochlea. Methods: Eight 3- to 4-month-old Mongolian gerbils were used as recipients. The animals received an intraperilymphatic transplantation of 100,000 green fluorescent protein (GFP)-positive MSCs with scala tympani injection and modiolar injection. Seven days after transplantation, MSC survival was evaluated by microscopic examination of frozen sections cut through the cochleae of the recipient animals. Results: MSCs isolated from the TgN (ACTbEGFP) mouse line used in this study exhibited bright green florescence after five to seven passages in vitro. Seven days after postoperatively, most transplanted MSCs were found in the scala tympani and scala vestibule and only a small number located in the scala media in animals that received both forms of injection. There were no GFP-positive MSCs in the modiolus in animals with scala tympani injection. In contrast, the mean profile count in animals with modiolar injection was 28, which was the highest in all regions. Although MSCs have the potential to migrate, the anatomic barrier between the perilymphatic space and the modiolus might account for the absence of GFP-positive MSCs in this region. Conclusion: These findings may have important clinical implications as a means of delivering MSCs in the cochlea for cell replacement therapy.

Objectives/Hypothesis: Individual speech and language outcomes of deaf children with cochlear implants (CIs) are quite varied. Individual differences in underlying cognitive functions may explain some of this variance. The current study investigated whether behavioral inhibition skills of deaf children were related to performance on a range of audiologic outcome measures. Design: Retrospective analysis of longitudinal data collected from prelingually and profoundly deaf children who used CIs. Methods: Behavioral inhibition skills were measured using a visual response delay task that did not require hearing. Speech and language measures were obtained from behavioral tests administered at 1-year intervals of CI use. Results: Female subjects showed higher response delay scores than males. Performance increased with length of CI use. Younger children showed greater improvement in performance as a function of device use than older children. No other subject variable had a significant effect on response delay score. A series of multiple regression analyses revealed several significant relations between delay task performance and open set word recognition, vocabulary, receptive language, and expressive language scores. Conclusions: The present results suggest that CI experience affects visual information processing skills of prelingually deaf children. Furthermore, the observed pattern of relations suggests that speech and language processing skills are closely related to the development of response delay skills in prelingually deaf children with CIs. These relations may reflect underlying verbal encoding skills, subvocal rehearsal skills, and verbally mediated self-regulatory skills. Clinically, visual response delay tasks may be useful in assessing behavioral and cognitive development in deaf children after implantation.

Objectives/Hypothesis: To discuss the underlying physiological and anatomical constraints on audiological performance of late-implanted prelingually deafened adult cochlear implant patients. Study Design: Retrospective review. Methods: Published literature on the topic of auditory pathway responses to prolonged congenital deafness was reviewed. In particular, the authors sought to identify the anatomical and physiological changes that take place in both the peripheral and central auditory pathways in response to prolonged deafness, as well as how they are altered by chronic electrical stimulation. Results: The currently available evidence suggests that the colonization of the auditory cortex by other sensory modalities is the main limiting factor in postimplantation performance, not the pathological degenerative changes of the auditory nerve, cochlear nucleus, or auditory midbrain. Conclusion: The reviewed evidence, although circumstantial, suggests that emphasizing aurally based educational programs before (with hearing aids) and after cochlear implantation could reduce the cortical colonization phenomenon and potentially improve postimplantation audiological performance of patients with long-term prelingual

Objectives/Hypothesis: To examine the hypothesis that the newer generations of cochlear implants could provide considerable speech understanding to late-implanted, prelingually deaf adult patients. Study Design: Retrospective review. Methods: Speech perception scores of 103 patients with long-term prelingual deafness obtained from the recent clinical trials were compared with other previously published results. Results: Unlike patients receiving implants in early childhood, the audiologic performance of most patients with long-term prelingual deafness rapidly approached asymptotic levels within 1 year after implantation. Beginning at 3 months postimplantation, statistically significant improvement was noted in their speech perception scores compared with their preimplant levels. However, the average performance plateau achieved by this group of patients was significantly below the levels published for postlingual patients. No statistically significant differences were observed between the test scores at any testing interval among patients with different devices. Conclusions: Most patients with long-term prelingual deafness achieve their performance plateau within 1 year after implantation. The results suggest that patient characteristics, rather than device properties, are likely to be the major contributing factor responsible for the observed audiologic outcomes.

Objectives In this investigation, we report the outcomes of 14 adults (age >18 y) and 9 children (age

The transmastoid facial recess approach has become the standard technique for cochlear implantation. Although this approach has been used for implantation in patients with common cavity deformities, it is not without increased risk to the facial nerve. Using a direct approach to the common cavity that circumvents the facial recess, we have successfully implanted four patients with common cavity deformities. An aberrant facial nerve in one patient would have precluded placement of the electrode array using standard cochlear implant techniques. As demonstrated in these four patients, the direct approach to the common cavity is an effective approach for placement of the electrode array, minimizes risk to the facial nerve, and may decrease the likelihood of postoperative cerebrospinal fluid leaks. Intraoperative video footage demonstrates the feasibility and facility of this approach in patients with common cavity deformities.

To examine the hypothesis that infants receiving a degraded auditory signal have more difficulty segmenting words from fluent speech if familiarized with the words presented in both speech and sign compared to familiarization with the words presented in speech only.Experiment utilizing an infant-controlled visual preference procedure.Twenty 8.5-month-old normal-hearing infants completed testing. Infants were familiarized with repetitions of words in either the speech + sign (n = 10) or the speech only (n = 10) condition. Infants were then presented with four six-sentence passages using an infant-controlled visual preference procedure. Every sentence in two of the passages contained the words presented in the familiarization phase, whereas none of the sentences in the other two passages contained familiar words.Infants exposed to the speech + sign condition looked at familiar word passages for 15.3 seconds and at nonfamiliar word passages for 15.6 seconds, t (9) = -0.130, p = .45. Infants exposed to the speech only condition looked at familiar word passages for 20.9 seconds and to nonfamiliar word passages for 15.9 seconds. This difference was statistically significant, t (9) = 2.076, p = .03.Infants' ability to segment words from degraded speech is negatively affected when these words are initially presented in simultaneous speech and sign. The current study suggests that a decreased ability to segment words from fluent speech may contribute towards the poorer performance of pediatric cochlear implant recipients in total communication settings on a wide range of spoken language outcome measures.

Objective: The loss of spiral ganglion neurons (SGNs) is one of the major causes of profound sensorineural hearing loss (SNHL). Stem cell replacement therapy, which is still in its infancy, has the potential to treat or cure those who suffer from an array of illnesses and degenerative neurologic disorders, including sensorineural deafness (SNHL). Little is known about the potentials of mesenchymal stem cells (MSCs) and their ability to take on properties of SGNs. The two main purposes of this study were to evaluate the survival of mouse MSCs transplanted into normal and ouabain-treated gerbil cochleae and to determine the migratory patterns of MSCs with two differing injection methods. Subjects: Thirty-two Mongolian gerbils, 3 to 4 months old, were used as recipients, and four 6-week-old TgN(ACTbEGFP) mice that ubiquitously express green fluorescent protein (GFP) were used as donors. Design: The animals were deafened by ouabain, which damaged SGNs while leaving hair cell systems intact. After 4 weeks of recovery, the animals received an intraperilymphatic transplantation of 1.0 × 106 GFP-positive undifferentiated MSCs via two different injection methods: scala tympani injection and modiolar injection. Seven days after the transplantation, the survival of MSCs was evaluated by microscopic examination of frozen sections cut through the cochleae of the recipient animals. The number of profiles was counted on the five most central modiolar sections. One-way analyses of variance (ANOVA) were used to determine any significantdifferences among mean profile counts across the experimental conditions. Results: Our findings indicated that undifferentiated MSCs were able to survive in the modiolus both in the control and the ouabain-treated cochleae. The average number of profiles found in the modiolus was greater in the ouabain-treated cochleae than in the control cochleae. This difference was statistically significant (P < .01) as determined using a one-way ANOVA and an ad hoc Tukey-Kramer's test. With the scala tympani injection, there were no profiles found in the modiolus either in the control or ouabain-treated cochleae. This finding may indicate that donor MSCs need to be directly injected into the modiolus to replace injured SGNs. Finally, there was no evidence of hyperacute rejection in any of the gerbils despite the use of xenotransplantation. Conclusions: These findings may have important clinical implications as a means of delivering MSCs in the cochlea for stem-cell replacement therapy. Survival of transplanted MSCs into the modiolus of the cochlea may result in regeneration of damaged SGNs.

Objectives/Hypothesis: To determine whether scores from a behavioral assessment of prelingually deafened children who present for cochlear implant surgery are predictive of audiological outcomes Study Design: Retrospective review of longitudinal data collected from 42 children with prelingual hearing loss who presented for a cochlear implant before age 5 years. Methods: The Vineland Adaptive Behavioral Scales (VABS) was administered during the preimplant workup. Standardized scores reflect daily living skills, socialization, and motor development compared with a normative sample. Regression analyses were conducted to determine whether any subject variables were related to VABS scores. Mixed-model analyses were computed to determine whether preimplant VABS scores were predictive of longitudinal spoken-language data obtained after cochlear implant surgery. Results: Motor scores tended to be higher than nonmotor scores. Nonmotor scores were significantly lower than the normative mean and decreased with testing age. Children with acquired deafness demonstrated lower motor scores than children with congenital causes. Children with higher motor scores demonstrated significantly higher performance on language, vocabulary, and word recognition tests than children with lower motor scores. Nonmotor domains were not as robustly related to spoken-language measures, although similar trends were observed Conclusion: Profound deafness and language delay may confound the assessment of daily living skills and socialization in the population studied. Motor development appears to proceed normally in prelingually deafened children and is a preimplant predictor of spoken-language outcome in young infants and children with cochlear implants, a finding consistent with the large body of work establishing links between perceptual-motor and language development.

Objective: Auditory neuropathy is a recently described clinical entity characterized by sensorineural hearing loss in which the auditory evoked potential (ABR) is absent but otoacoustic emissions are present. This suggests a central locus for the associated hearing loss. In this study the results observed in a child with auditory neuropathy who received a cochlear implant are presented and compared with those of a matched group of children who were recipients of implants. Methods: A single-subject, repeated-measures design, evaluating closed-set and open-set word recognition abilities was used to assess the subject and a control group of matched children with implants who had also experienced a progressive sensorineural hearing loss. Results: The subject demonstrated improvements in vowel recognition (82% correct) by 1 year after implantation, which were only slightly lower than the control group. Consonant recognition and open-set word recognition scores were significantly lower. Conclusion : Caution should be exercised when considering cochlear implantation in children with auditory neuropathy. As with conventional hearing aids, less than optimal results may be seen.

This study examined the variables that contribute to the large individual differences in the speech perception skills of children with the Nucleus multichannel cochlear implant. Sixty-one children were tested on four measures of speech perception: two tests of closed-set word recognition, one test of open-set recognition of phrases, and one open-set monosyllabic word test, scored on the basis of the percentage of phonemes as well as words identified correctly. The results of a series of multiple regression analyses revealed that the variables of processor type, duration of deafness, communication mode, age at onset of deafness, length of implant use, and age implanted accounted for roughly 35% of the variance on two tests of closed-set word recognition, and 40% of the variance on measures that assessed recognition of words or phomenes in an open set. Length of implant use accounted for the most variance on all of the speech perception measures.

• 21.4% of children developed hearing loss, a percentage similar to previous population studies. • Since all received treatment, we cannot determine directly bisphosphonate effects on hearing loss over time. • However, it appears that bisphosphonates neither increase hearing loss nor stop progression in these children. CONCLUSIONS • Osteogenesis Imperfecta (OI) is a genetic disorder of collagen synthesis. It is commonly associated with increased fracture rate, decreased bone mineral density (BMD), and blue sclerae. • It is also associated with hearing loss, sensorineural and/or conductive, which progresses with age. Hearing loss is most prevalent in OI Type I. • There are several forms of OI ranging in severity: -Type I, mild with blue sclerae -Type II, perinatally lethal -Type III, progressively deforming with white sclerae -Type IV, severe with white sclerae -Additional severe forms also described (Types V, VI, VII) • Treatment includes IV or oral bisphosphonates to increase bone density, decrease fracture rate, and decrease bony pain. • Bisphosphonates have been associated with osteonecrosis of the mandible and osteopetrosis of long bones in some cases. • Effects of bisphosphonates on hearing, specifically the middle ear ossicles and cochlea, have not yet been determined. BACKGROUND Figure 2: Femoral bowing in an OI type III patient. Lucencies between lines along the epiphyses signify bone growth following treatment with bisphosphonates. METHODS

Glomus jugulare tumors have the ability to synthesize, store, and secrete biogenic amines. Although the majority of these tumors remain endocrinologically silent, on rare occasions they present either as a pheochromocytoma or with a carcinoid syndrome. We report a 20-year-old male with two intracranial tumors: an intrasellar neoplasm and a glomus jugulare tumor. Catecholamine catabolites in the urine were not increased, and blood pressure was always normal. The pituitary tumor was an adenoma, immunostaining positive for prolactin. The second patient, a 29-year-old hypertensive male, with a glomus jugulare tumor, had increased vanillylmandelic-acid excretion. In both cases, the paraganglioma tumor cells contained numerous dense-core vesicles (125 to 380 nm in diameter) in electron microscopy, and showed intense fluorescence by the sucrose-potassium phosphate-glyoxylic acid method. Using high-performance liquid chromatography and microspectrofluorometry we were able to establish the presence of large amounts of dopamine in the cytoplasm of the tumor cells.

Fifteen profoundly deaf patients under the age of 18 years have received a 3M/House cochlear implant. The surgical procedure employed is essentially the same as that used in adults with a few modifications to accommodate for the smaller dimensions of the mastoid process and the thinness of the scalp and temporal squama. Pediatric subjects receive timing and intensity information at similar thresholds as adults implanted with this device which contributes to improvement in speech production to various degrees. All subject groups demonstrated significant language delays as a result of their profound hearing losses. Postimplantation, more growth was seen in receptive than in expressive language skills. However, the growth observed did not exceed that expected in profoundly deaf children as reported in the literature. Language growth as a result of the cochlear implant alone is yet to be documented in our patients.