1,720,999 research outputs found
Outcomes in nontumor adults fitted with the auditory brainstem implant: 10 Years' experience
No full textOBJECTIVES: Recently, open-set speech recognition performance has been observed with electric stimulation of the brainstem in some nontumor (NT) patients. These outcomes require that we reevaluate the criteria for patient selection and the rationale for expanding the application for the auditory brainstem implant (ABI) to NT adult patients with profound hearing loss. This study presents results from up to 10 years in adults, with analysis based on cause. MATERIALS AND METHODS: In our Department, from April 1997 to September 2007, ABIs have been implanted in 112 patients (83 adults and 29 children) with tumor (T) and NT disorders. Of the 112 patients, 15 have previously had a cochlear implant elsewhere with no sound detection. This article presents speech recognition results from the 80 patients (32 neurofibromatosis type 2 and 48 NT) who had achieved at least 1-year follow-up. The retrosigmoid approach was used in all NT patients, and the retrosigmoid-transmeatal approach was used in all T patients. RESULTS: All patients had a functioning implantation, and no complications were observed during the operation, activation, or long-term use of the ABI. At the most recent follow-up, NT adults scored from 10 to 100% in open-set speech perception tests (average, 59%), and T patients scored from 5 to 31% (average, 10%). The differences between these results are statistically significant (p = 0.0007). The best performance was observed in patients who lost their nerve VIII from head trauma or severe ossification. Lowest performance (although still highly beneficial to the patient) was observed in patients with neurologic disorders, neuropathy, and cochlear malformations. CONCLUSION: Our experience clearly indicates that the ABI is an effective tool for hearing rehabilitation in patients with profound hearing loss who cannot be fitted with cochlear implants
TORP vs round window implant for hearing restoration of patients with extensive ossicular chain defect.
No full textCONCLUSIONS: Round window implant (RWI) with a floating mass transducer (FMT) may be suggested as the first choice in hearing rehabilitation for patients with chronic otitis media (COM) and extensive destruction of the ossicular chain. OBJECTIVE: To investigate the pros and cons of the total ossicular replacement prosthesis (TORP) vs the RWI in restoration of hearing in patients with COM. PATIENTS AND METHODS: Thirty-eight patients with bilateral moderate to severe mixed or conductive hearing loss from COM without cholesteatoma and bilateral ossicular chain erosion (footplate residual) were alternately assigned to a titanium-TORP (T-TORP) and to RWI with the FMT of the Medel Vibrant Soundbridge (MVBS) located onto the RW niche. The therapeutic efficiency, preoperative vs postoperative air-conduction gain and speech recognition were investigated for the two groups and statistically analyzed at 36 months postoperatively. The following postoperative anatomic conditions were also evaluated for the two groups: 1) recurrence of infection, 2) retraction pocket, 3) extrusion rate, and 4) displacement of the prosthesis. RESULTS: Good functional results and stability at 36 months were obtained with both procedures. The extrusion rates for T-TORP were low. So far no extrusion has been observed for RWI. Hearing results were statistically much better for RWI vs T-TORP for all investigated parameters
Vestibular Neurectomy and Microvascular Decompression of the Cochlear Nerve in Meniere's Disease.
No full textVestibular neurectomy (VN) results in a high success rate in the control of vertigo in Meniere's disease, although the subsequent fate of auditory function is fairly unpredictable. The present investigation reports the postoperative results obtained in a group of 30 subjects with a clinical diagnosis of Meniere's disease and vascular cross-compression of cranial nerve VIII. All subjects underwent VN using a retrosigmoid approach, and in half of them microvascular decompression (MVD) of the cochlear nerve with interposition of autogenous muscle was performed at the same time. All patients had complete relief from vertigo. Hearing was significantly improved in the VN-MVD group (46.7% of subjects). In this group tinnitus and aural fullness also improved significantly, with values of 62.6% and 66.6%, respectively
Extrusion of corpora amylacea from the marginal gila at the vestibular root entry zone.
No full textWe have studied the vestibular nerve in patients suffering from Meniere's disease and vascular cross-compression syndrome of the root entry zone due to close contact with the nerve of the antero-inferior cerebellar artery or one of its branches. All patients underwent vestibular neurectomy using the restrosigmoid approach which allows the resection of a relatively long nerve segment. In all the studied vestibular nerves a central and a peripheral zone could be distinguished. In the central zone, a massive accumulation of corpora amylacea (CA) was detected in the cytoplasm of astrocytes. Many CA were seen to protrude from the central nervous system into the pial connective tissue. These structures resembled sessile or pedunculated polyps, with a complex system of scissurae at their bases. CA were also found in extracellular location in the pial connective tissue near capillaries, and not wrapped by membranes. Our findings suggest that after their production in astrocytes, CA are transferred into the pial connective tissue across the glial-limiting lamina. Thus, the present results indicate that CA do not merely represent an accumulation of abnormal material, but they could instead be part of a glio-pial system devoted to the clearance of substances from the nervous system
To hear or not to hear: Sound Availability Modulates Sensory-Motor Integration
Full text linkWhen we walk in place with our eyes closed after a few minutes of walking on a treadmill, we experience an unintentional forward body displacement (drift), called the sensory-motor aftereffect. Initially, this effect was thought to be due to the mismatch experienced during treadmill walking between the visual (absence of optic flow signaling body steadiness) and proprioceptive (muscle spindles firing signaling body displacement) information. Recently, the persistence of this effect has been shown even in the absence of vision, suggesting that other information, such as the sound of steps, could play a role. To test this hypothesis, six cochlear-implanted individuals were recruited and their forward drift was measured before (Control phase) and after (Post Exercise phase) walking on a treadmill while having their cochlear system turned on and turned off. The relevance in testing cochlear-implanted individuals was that when their system is turned off, they perceive total silence, even eliminating the sounds normally obtained from bone conduction. Results showed the absence of the aftereffect when the system was turned off, underlining the fundamental role played by sounds in the control of action and breaking new ground in the use of interactive sound feedback in motor learning and motor development
Complications in auditory brainstem implant surgery in adults and children.
No full textObjective: Surgery for hearing restoration with auditory brainstem
implantation (ABI) in patients with neurofibromatosis
type 2 (NF2) is considered safe, as no increase in postoperative
complications related to surgery or device implantation has
been observed. Over the last 10 years, we have extended the
use of ABI to nontumor (NT) adults and children with cochlear
or cochlear nerve malfunctions who would not or did not benefit
from a cochlear implant (CI). This article examines the
complications encountered in ABI surgery in all patient groups.
Study Design: Retrospective case review.
Setting: Tertiary referral center.
Patients: One hundred fourteen ABI operations were performed
in Verona (Italy) from 1997 to 2008 in 83 adults and
31 children. Thirty-six had NF2 (34 adults and 2 children), and
78 (49 adults and 29 children) had NT cochlear and cochlear
nerve disorders.
Intervention: A retrosigmoid-transmeatal approach was used
in the NF2 cases, and a simple retrosigmoid approach was used
in the NT patients.
Main Outcome Measures: Surgical complications are tabulated
according to standard reporting categories and are presented
separately and analyzed statistically for NF2, NT
adults, and NT children. Complication rates are compared
with those of CI and microvascular decompression surgery.
Results: ABI surgery has a very low major complication rate,
particularly in non-NF2 patients. Minor complications were
easily controlled with complete resolution in all cases. Although
the potential complications of intradural ABI implantation
are more severe than those of a transmastoid approach for
CIs, the actual observed complication rates in ABI candidates
without NF2 tumors are comparable to those of CI surgery in
both adults and children.
Conclusion: This study demonstrates that the ABI is a safe
procedure when performed by an experienced surgical and
rehabilitation team, and its benefits can be extended to a larger
population of deaf patients
A case of brown tumor of the vomer [Osservazione di un caso di tumore bruno del vomere.]
No full textA case of brown-tumor of the vomer in a 21-year-old woman is described. The term giant cell lesions encompasses a variety of conditions. Three distinct entities are found in the facial area i.e. giant cell reparative granuloma, true giant cell tumor and brown-tumor. After having described the clinical, radiological and histopathological characteristics of the lesion, emphasis is placed on the importance of clinical, anamnestic, laboratory, radiological and histological findings in accurately differentiating the various types of giant cell lesions of the facial skeleton
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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