Cor pulmonale in a patient with Brown-Vialetto-Van Laere syndrome: A case report

Brown-Vialetto-Van Laere syndrome (BVVLS) is a rare neurological disease characterized by sensorineural hearing loss and multiple cranial nerve palsies, usually involving the VIIth and IXth to XIIth cranial nerves. We describe the clinical and pathological features of a 33-year-old woman with BVVLS. The patient developed progressive exertional dyspnea, with clinical and laboratory findings of right-sided heart failure and pulmonary hypertension. She developed status epilepticus in the setting of cardiac deterioration and respiratory infection, and died of cardiogenic and septic shock. Autopsy disclosed bilateral neuronal loss and gliosis in the inferior colliculi, locus coeruleus and facial and vestibular nuclei. Cor pulmonale is a complication of hypoventilation-induced hypoxia and hypercapnia and had not yet been reported in BVVLS. (C) 2010 Elsevier B.V. All rights reserved.

Development of a digital hearing aid to meet the Brazilian Government`s Ordinance 587 (APAC) - Health Department

The treatment of sensorineural hearing loss is based on hearing aids, also known as individual sound amplification devices. The hearing aids purchased by the Brazilian Government, aiming at fulfilling public policies, are based on dedicated components, which bring about benefits, but also render them expensive and may impair repair services after manufacture`s warranty expires. Aim: to design digital behind-the-ear hearing aids built from standardized components coming from the very supply chain of these manufacturers. Study design: experimental. Materials and Methods: to identify the supply chain of these manufacturers, request samples and set up hearing aids in the laboratory. Results: The developed hearing aids did not show lesser electroacoustic characteristics when compared to those acquired by the Government, also being tested by the same reference international technical standard. Conclusion: It is possible to develop digital behind-the-ear hearing aids based on off-the-shelf components from hearing aid manufacturers` supply chain. Their advantages include low operational costs - for acquisition (with clear advantages for the Government) and service (advantage for the patient).

Microangiopathy of the inner ear, deafness, and cochlear implantation in a patient with Susac syndrome

Conclusion: The cochlear implant was beneficial as an attempt to restore hearing and improve communication abilities in this patient with profound sensorineural hearing loss secondary to Susac syndrome. Objective: To report the audiological outcomes of cochlear implantation (CI) in a young woman with Susac syndrome after a 6-month follow-up period. Susac syndrome is a rare disorder. It is clinically characterized by a typical triad of sensorineural deafness, encephalopathy, and visual defect, due to microangiopathy involving the brain, inner ear, and retina. Methods: This was a retrospective review of a case at a tertiary referral center. After diagnosis, the patient was evaluated by a multidisciplinary team and received a cochlear implant in her right ear. Results: The patient achieved 100% open-set sentence recognition in noise conditions and 92% monosyllable and 68% medial consonant recognition in quiet conditions after 6 months of implant use. She reported the use of the telephone 3 months after activation.

Selective Inner Hair Cell Loss in Prematurity: A Temporal Bone Study of Infants from a Neonatal Intensive Care Unit

Premature birth is a well-known risk factor for sensorineural hearing loss in general and auditory neuropathy in particular. However, relatively little is known about the underlying causes, in part because there are so few relevant histopathological studies. Here, we report on the analysis of hair cell loss patterns in 54 temporal bones from premature infants and a control group of 46 bones from full-term infants, all of whom spent time in the neonatal intensive care unit at the Hospital de Nios in San Jose, Costa Rica, between 1977 and 1993. The prevalence of significant hair cell loss was higher in the preterm group than the full-term group (41% vs. 28%, respectively). The most striking finding was the frequency of selective inner hair cell loss, an extremely rare histopathological pattern, in the preterm vs. the full-term babies (27% vs. 3%, respectively). The findings suggest that a common cause of non-genetic auditory neuropathy is selective loss of inner hair cells rather than primary damage to the cochlear nerve.

Effects of hyperbaric oxygen treatment on auditory hair cells after acute noise damage

Acute acoustic trauma (AAT) is a sudden sensorineural hearing loss caused by exposure of the hearing organ to acoustic overstimulation, typically an intense sound impulse, hyperbaric oxygen therapy (HOT), which favors repair of the microcirculation, can be potentially used to treat it. Hence, this study aimed to assess the effects of HOT on guinea pigs exposed to acoustic trauma. Fifteen guinea pigs were exposed to noise in the 4-kHz range with intensity of 110 dB sound level pressure for 72 h. They were assessed by brainstem auditory evoked potential (BAEP) and by distortion product otoacoustic emission (DPOAE) before and after exposure and after HOT at 2.0 absolute atmospheres for 1 h. The cochleae were then analyzed using scanning electron microscopy (SEM). There was a statistically significant difference in the signal-to-noise ratio of the DPOAE amplitudes for the 1- to 4-kHz frequencies and the SEM findings revealed damaged outer hair cells (OHC) after exposure to noise, with recovery after HOT (p = 0.0159), which did not occur on thresholds and amplitudes to BAEP (p = 0.1593). The electrophysiological BAEP data did not demonstrate effectiveness of HOT against AAT damage. However, there was improvement of the anatomical pattern of damage detected by SEM, with a significant reduction of the number of injured cochlear OHC and their functionality detected by DPOAE.

Multi-system neurological disease is common in patients with OPA1 mutations

Additional neurological features have recently been described in seven families transmitting pathogenic mutations in OPA1, the most common cause of autosomal dominant optic atrophy. However, the frequency of these syndromal `dominant optic atrophy plus` variants and the extent of neurological involvement have not been established. In this large multi-centre study of 104 patients from 45 independent families, including 60 new cases, we show that extra-ocular neurological complications are common in OPA1 disease, and affect up to 20% of all mutational carriers. Bilateral sensorineural deafness beginning in late childhood and early adulthood was a prominent manifestation, followed by a combination of ataxia, myopathy, peripheral neuropathy and progressive external ophthalmoplegia from the third decade of life onwards. We also identified novel clinical presentations with spastic paraparesis mimicking hereditary spastic paraplegia, and a multiple sclerosis-like illness. In contrast to initial reports, multi-system neurological disease was associated with all mutational subtypes, although there was an increased risk with missense mutations [odds ratio = 3.06, 95% confidence interval = 1.44-6.49; P = 0.0027], and mutations located within the guanosine triphosphate-ase region (odds ratio = 2.29, 95% confidence interval = 1.08-4.82; P = 0.0271). Histochemical and molecular characterization of skeletal muscle biopsies revealed the presence of cytochrome c oxidase-deficient fibres and multiple mitochondrial DNA deletions in the majority of patients harbouring OPA1 mutations, even in those with isolated optic nerve involvement. However, the cytochrome c oxidase-deficient load was over four times higher in the dominant optic atrophy + group compared to the pure optic neuropathy group, implicating a causal role for these secondary mitochondrial DNA defects in disease pathophysiology. Individuals with dominant optic atrophy plus phenotypes also had significantly worse visual outcomes, and careful surveillance is therefore mandatory to optimize the detection and management of neurological disability in a group of patients who already have significant visual impairment.

Birth Prevalence and Natural History of Congenital Cytomegalovirus Infection in a Highly Seroimmune Population

Background. The natural history of congenital cytomegalovirus (CMV) infection is scarcely known in populations with high maternal CMV seroprevalence. This study evaluated the birth prevalence, clinical findings at birth, and hearing outcome in CMV-infected children from such a population. Methods. Consecutively born infants were screened for the presence of CMV in urine and/or saliva specimens during the first 2 weeks after birth. Neonatal clinical findings were recorded, and CMV-infected children were tested to document hearing function during follow-up. A subset of mothers of CMV-infected infants were prenatally tested for the presence of anti-CMV immunoglobulin G antibodies. Results. Congenital CMV infection was confirmed in 87 (1.08%; 95% confidence interval [CI], 0.86%-1.33%) of 8047 infants. Seven infants (8.1%; 95% CI, 3.3%-15.9%) had at least 1 clinical finding suggestive of CMV infection, and 4 (4.6%; 95% CI, 1.3%-11.3%) had 13 findings of systemic disease. Sensorineural hearing loss was found in 5 (8.6%; 95% CI, 2.9%-19.0%) of 58 children tested at a median age of 21 months. Bilateral profound hearing loss was observed in 2 children, and the hearing threshold was 160 decibels in all 5 children with hearing loss, including 2 children born to mothers with probable nonprimary CMV infection. Conclusions. The results of this large newborn screening study in a population with high CMV seroimmunity provide additional evidence that congenital CMV disease occurs in populations with high seroprevalence rates, with a similar incidence of CMV-related hearing loss to that reported in the offspring of women from populations in developed countries with lower rates of seroimmunity to CMV.

Audiological findings in pacients treated with radiotherapy for head and neck tumors

Radiotherapy has been widely used given its increase in the successful outcomes and cure of some cancers. Aim: To evaluate the functionality of the auditory system in patients who underwent radiotherapy treatment for head and neck tumors. Materials and Methods: From May 2007 to May 2008, otorhinolaryngological and audiological evaluation (Pure Tone Audiometry (air and bone conduction), Speech Audiometry, Tympanometry, Acoustic Reflex testing and Distortion Product Otoacoustic Emissions) were performed in 19 patients diagnosed with head and neck neoplasia and treated with radiotherapy. Prospective case series study. Results: 10.5% left ears and 26.3% right ears had bilateral hearing loss soon after radiotherapy according to ASHA criteria. Conclusions: Radiotherapy treatment for head and neck cancer has ototoxic effects. Early programs of auditory rehabilitation should be offered to these patients.

Auditory steady state response in pediatric audiology

The main issue regarding pediatric audiology diagnosis is determining procedures to configure reliable results which can be used to predict frequency-specific hearing thresholds. Aim: To investigate the correlation between auditory steady-state response (ASSR) with other tests in children with sensorineural hearing loss. Methods: Prospective cross-sectional contemporary cohort study. Twenty-three children (ages 1 to 7; mean, 3 years old) were submitted to ASSR, behavioral audiometry, click audiometry brain stem response (ABR), tone burst ABR, and predicting hearing level from the acoustic reflex. Results: the correlation between behavioral thresholds and ASSR was (0.70- 0.93), for the ABR tone burst it was (0.73 -0.93), for the ABR click it was (0.83-0.89) only at 2k and 4 kHz. The match between the ASSR and the hearing threshold prediction rule was considered moderate. Conclusion: there was a significant correlation between the ASSR and audiometry, as well as between ABR click (2k and 4 kHz) and for the ABR tone burst. The acoustic reflex can be used to add information to diagnosis in children.

The universal newborn hearing screening in Brazil: From identification to intervention

Objective: The objective of the study is to investigate the results of the newborn hearing screening program carried out in a Public Hospital in Brazil, in the first 3 years regarding: (1) the prevalence of hearing impairment; (2) the influence of the universal hearing screening program on the age at which the diagnosis of hearing loss is defined; (3) the cost effectiveness of the program; (4) the outcomes, in terms of the age in which the hearing rehabilitation started. Methods: A descriptive study of the first 3 years after starting the universal newborn hearing screening in a Public Hospital of Bauru, Sao Paulo state, Brazil. The screening method consists of a two-stage screening approach with transient otoacoustic emissions (TOAE), conducted by an audiologist. If the outcome in the second-stage screening is REFER, the infant is submitted to diagnostic follow-up testing and intervention at the Audiology and Speech Pathology Clinic at the University of Sao Paulo, campus of Bauru. The evaluation of the costs of the universal newborn hearing screening program per each screened newborn (around 4000/year) was done based on a proposal by the National Center for Hearing Assessment and Management, of the Utah State University, United States of America. Results: 11,466 newborns were submitted to hearing screening, corresponding to 90.52% of the living newborns. The prevalence of sensorineural hearing loss was 0.96:1000. Of the 11 children with sensorineural hearing loss, eight children received hearing aids and five started the therapeutic process before the age of 1. Currently, four children between the ages of 11 months and 2 years old were submitted to cochlear implant surgery. The cost of hearing screening was US$7.00 and the annual cost of the universal newborn hearing screening program was US$26,940.47. Conclusion: The hospital-based universal newborn hearing screening carried out through the Brazilian National Health System is viable, with promising results. However, in a country such as Brazil, which presents large socio-economic differences, the same type of analyses should be performed in several regions, so as to take into account specific aspects, to implement the newborn hearing screening along with the Public System. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

The search of a genetic basis for noise-induced hearing loss (NIHL)

Background and aim: Knowledge about the genetic factors responsible for noise-induced hearing loss (NIHL) is still limited. This study investigated whether genetic factors are associated or not to susceptibility to NIHL. Subjects and methods: The family history and genotypes were studied for candidate genes in 107 individuals with NIHL, 44 with other causes of hearing impairment and 104 controls. Mutations frequently found among deaf individuals were investigated (35delG, 167delT in GJB2, Delta(GJB6- D13S1830), Delta(GJB6- D13S1854) in GJB6 and A1555G in MT-RNR1 genes); allelic and genotypic frequencies were also determined at the SNP rs877098 in DFNB1, of deletions of GSTM1 and GSTT1 and sequence variants in both MTRNR1 and MTTS1 genes, as well as mitochondrial haplogroups. Results: When those with NIHL were compared with the control group, a significant increase was detected in the number of relatives affected by hearing impairment, of the genotype corresponding to the presence of both GSTM1 and GSTT1 enzymes and of cases with mitochondrial haplogroup L1. Conclusion: The findings suggest effects of familial history of hearing loss, of GSTT1 and GSTM1 enzymes and of mitochondrial haplogroup L1 on the risk of NIHL. This study also described novel sequence variants of MTRNR1 and MTTS1 genes.

Role of the Mitochondrial Mutations, m. 827A > G and the Novel m. 7462C > T, in the Origin of Hearing Loss

Samples from 30 deaf probands exhibiting features suggestive of syndromic mitochondrial deafness or from families with maternal transmission of deafness were selected for investigation of mutations in the mitochondrial genes MT-RNR1 and MT-TS1. Patients with mutation m. 1555A>G had been previously excluded from this sample. In the MT-RNR1 gene, five probands presented the m. 827A>G sequence variant, of uncertain pathogenicity. This change was also detected in 66 subjects of an unaffected control sample of 306 Brazilian individuals from various ethnic backgrounds. Given its high frequency, we consider it unlikely to have a pathogenic role on hereditary deafness. As to the MT-TS1 gene, one proband presented the previously known pathogenic m. 7472insC mutation and three probands presented a novel variant, m. 7462C>T, which was absent from the same control sample of 306 individuals. Because of its absence in control samples and association with a family history of hearing impairment, we suggest it might be a novel pathogenic mutation.